Hydrophilic contact lenses worn for an extended period or permanently.
Lenses designed to be worn on the front surface of the eyeball. (UMDNS, 1999)
Soft, supple contact lenses made of plastic polymers which interact readily with water molecules. Many types are available, including continuous and extended-wear versions, which are gas-permeable and easily sterilized.
Apparatus, devices, or supplies intended for one-time or temporary use.
Sterile solutions used to clean and disinfect contact lenses.
Absence of the crystalline lens resulting from cataract extraction.
Inflammation of the cornea.
An excessive amount of fluid in the cornea due to damage of the epithelium or endothelium causing decreased visual acuity.
Diseases of the cornea.
Loss of the tooth substance by chemical or mechanical processes
A broad family of synthetic organosiloxane polymers containing a repeating silicon-oxygen backbone with organic side groups attached via carbon-silicon bonds. Depending on their structure, they are classified as liquids, gels, and elastomers. (From Merck Index, 12th ed)
Infection of the cornea by an ameboid protozoan which may cause corneal ulceration leading to blindness.
Pieces of glass or other transparent materials used for magnification or increased visual acuity.
The transparent anterior portion of the fibrous coat of the eye consisting of five layers: stratified squamous CORNEAL EPITHELIUM; BOWMAN MEMBRANE; CORNEAL STROMA; DESCEMET MEMBRANE; and mesenchymal CORNEAL ENDOTHELIUM. It serves as the first refracting medium of the eye. It is structurally continuous with the SCLERA, avascular, receiving its nourishment by permeation through spaces between the lamellae, and is innervated by the ophthalmic division of the TRIGEMINAL NERVE via the ciliary nerves and those of the surrounding conjunctiva which together form plexuses. (Cline et al., Dictionary of Visual Science, 4th ed)
A genus of free-living soil amoebae that produces no flagellate stage. Its organisms are pathogens for several infections in humans and have been found in the eye, bone, brain, and respiratory tract.
Loss of epithelial tissue from the surface of the cornea due to progressive erosion and necrosis of the tissue; usually caused by bacterial, fungal, or viral infection.
The fluid secreted by the lacrimal glands. This fluid moistens the CONJUNCTIVA and CORNEA.
Occlusal wear of the surfaces of restorations and surface wear of dentures.
The fitting and adjusting of artificial parts of the body. (From Stedman's, 26th ed)
A noninflammatory, usually bilateral protrusion of the cornea, the apex being displaced downward and nasally. It occurs most commonly in females at about puberty. The cause is unknown but hereditary factors may play a role. The -conus refers to the cone shape of the corneal protrusion. (From Dorland, 27th ed)
Artificial implanted lenses.
Absence of crystalline lens totally or partially from field of vision, from any cause except after cataract extraction. Aphakia is mainly congenital or as result of LENS DISLOCATION AND SUBLUXATION.
A vinyl polymer made from ethylene. It can be branched or linear. Branched or low-density polyethylene is tough and pliable but not to the same degree as linear polyethylene. Linear or high-density polyethylene has a greater hardness and tensile strength. Polyethylene is used in a variety of products, including implants and prostheses.
The measurement of curvature and shape of the anterior surface of the cornea using techniques such as keratometry, keratoscopy, photokeratoscopy, profile photography, computer-assisted image processing and videokeratography. This measurement is often applied in the fitting of contact lenses and in diagnosing corneal diseases or corneal changes including keratoconus, which occur after keratotomy and keratoplasty.
Infections in the inner or external eye caused by microorganisms belonging to several families of bacteria. Some of the more common genera found are Haemophilus, Neisseria, Staphylococcus, Streptococcus, and Chlamydia.
A network of cross-linked hydrophilic macromolecules used in biomedical applications.
Partial or complete opacity on or in the lens or capsule of one or both eyes, impairing vision or causing blindness. The many kinds of cataract are classified by their morphology (size, shape, location) or etiology (cause and time of occurrence). (Dorland, 27th ed)
Refraction of LIGHT effected by the media of the EYE.
The portion of the crystalline lens surrounding the nucleus and bound anteriorly by the epithelium and posteriorly by the capsule. It contains lens fibers and amorphous, intercellular substance.
The thin noncellular outer covering of the CRYSTALLINE LENS composed mainly of COLLAGEN TYPE IV and GLYCOSAMINOGLYCANS. It is secreted by the embryonic anterior and posterior epithelium. The embryonic posterior epithelium later disappears.
A pair of ophthalmic lenses in a frame or mounting which is supported by the nose and ears. The purpose is to aid or improve vision. It does not include goggles or nonprescription sun glasses for which EYE PROTECTIVE DEVICES is available.
A refractive error in which rays of light entering the EYE parallel to the optic axis are brought to a focus in front of the RETINA when accommodation (ACCOMMODATION, OCULAR) is relaxed. This results from an overly curved CORNEA or from the eyeball being too long from front to back. It is also called nearsightedness.
The core of the crystalline lens, surrounded by the cortex.
Synthetic thermoplastics that are tough, flexible, inert, and resistant to chemicals and electrical current. They are often used as biocompatible materials for prostheses and implants.
Rendering pathogens harmless through the use of heat, antiseptics, antibacterial agents, etc.
Measurement of light given off by fluorescein in order to assess the integrity of various ocular barriers. The method is used to investigate the blood-aqueous barrier, blood-retinal barrier, aqueous flow measurements, corneal endothelial permeability, and tear flow dynamics.
Water swollen, rigid, 3-dimensional network of cross-linked, hydrophilic macromolecules, 20-95% water. They are used in paints, printing inks, foodstuffs, pharmaceuticals, and cosmetics. (Grant & Hackh's Chemical Dictionary, 5th ed)
'Lens diseases' is a broad term referring to various pathological conditions affecting the lens of the eye, including cataracts, subluxation, and dislocation, which can lead to visual impairment or blindness if not managed promptly.
Clarity or sharpness of OCULAR VISION or the ability of the eye to see fine details. Visual acuity depends on the functions of RETINA, neuronal transmission, and the interpretative ability of the brain. Normal visual acuity is expressed as 20/20 indicating that one can see at 20 feet what should normally be seen at that distance. Visual acuity can also be influenced by brightness, color, and contrast.
Insertion of an artificial lens to replace the natural CRYSTALLINE LENS after CATARACT EXTRACTION or to supplement the natural lens which is left in place.
OPPORTUNISTIC INFECTIONS with the soil fungus FUSARIUM. Typically the infection is limited to the nail plate (ONYCHOMYCOSIS). The infection can however become systemic especially in an IMMUNOCOMPROMISED HOST (e.g., NEUTROPENIA) and results in cutaneous and subcutaneous lesions, fever, KERATITIS, and pulmonary infections.
The presence of an infectious agent on instruments, prostheses, or other inanimate articles.
The normal decreasing elasticity of the crystalline lens that leads to loss of accommodation.
Unequal curvature of the refractive surfaces of the eye. Thus a point source of light cannot be brought to a point focus on the retina but is spread over a more or less diffuse area. This results from the radius of curvature in one plane being longer or shorter than the radius at right angles to it. (Dorland, 27th ed)
A biocompatible, hydrophilic, inert gel that is permeable to tissue fluids. It is used as an embedding medium for microscopy, as a coating for implants and prostheses, for contact lenses, as microspheres in adsorption research, etc.
The methyl esters of methacrylic acid that polymerize easily and are used as tissue cements, dental materials, and absorbent for biological substances.
Infection by a variety of fungi, usually through four possible mechanisms: superficial infection producing conjunctivitis, keratitis, or lacrimal obstruction; extension of infection from neighboring structures - skin, paranasal sinuses, nasopharynx; direct introduction during surgery or accidental penetrating trauma; or via the blood or lymphatic routes in patients with underlying mycoses.
Stratified squamous epithelium that covers the outer surface of the CORNEA. It is smooth and contains many free nerve endings.
A heterogeneous family of water-soluble structural proteins found in cells of the vertebrate lens. The presence of these proteins accounts for the transparency of the lens. The family is composed of four major groups, alpha, beta, gamma, and delta, and several minor groups, which are classed on the basis of size, charge, immunological properties, and vertebrate source. Alpha, beta, and delta crystallins occur in avian and reptilian lenses, while alpha, beta, and gamma crystallins occur in all other lenses.
Malfunction of implantation shunts, valves, etc., and prosthesis loosening, migration, and breaking.
Deviations from the average or standard indices of refraction of the eye through its dioptric or refractive apparatus.
Each of the upper and lower folds of SKIN which cover the EYE when closed.
An alternative to REFRACTIVE SURGICAL PROCEDURES. A therapeutic procedure for correcting REFRACTIVE ERRORS. It involves wearing CONTACT LENSES designed to force corrective changes to the curvature of the CORNEA that remain after the lenses are removed. The effect is temporary but is maintained by wearing the therapeutic lenses daily, usually during sleep.
Infection, moderate to severe, caused by bacteria, fungi, or viruses, which occurs either on the external surface of the eye or intraocularly with probable inflammation, visual impairment, or blindness.
The plan and delineation of prostheses in general or a specific prosthesis.
Incomplete rupture of the zonule with the displaced lens remaining behind the pupil. In dislocation, or complete rupture, the lens is displaced forward into the anterior chamber or backward into the vitreous body. When congenital, this condition is known as ECTOPIA LENTIS.
The lamellated connective tissue constituting the thickest layer of the cornea between the Bowman and Descemet membranes.
A refractive error in which rays of light entering the eye parallel to the optic axis are brought to a focus behind the retina, as a result of the eyeball being too short from front to back. It is also called farsightedness because the near point is more distant than it is in emmetropia with an equal amplitude of accommodation. (Dorland, 27th ed)
Substances used on inanimate objects that destroy harmful microorganisms or inhibit their activity. Disinfectants are classed as complete, destroying SPORES as well as vegetative forms of microorganisms, or incomplete, destroying only vegetative forms of the organisms. They are distinguished from ANTISEPTICS, which are local anti-infective agents used on humans and other animals. (From Hawley's Condensed Chemical Dictionary, 11th ed)
Polymers of silicone that are formed by crosslinking and treatment with amorphous silica to increase strength. They have properties similar to vulcanized natural rubber, in that they stretch under tension, retract rapidly, and fully recover to their original dimensions upon release. They are used in the encapsulation of surgical membranes and implants.
The organ of sight constituting a pair of globular organs made up of a three-layered roughly spherical structure specialized for receiving and responding to light.
The science dealing with the establishment and maintenance of health in the individual and the group. It includes the conditions and practices conducive to health. (Webster, 3d ed)
Replacement for a hip joint.
Corneal and conjunctival dryness due to deficient tear production, predominantly in menopausal and post-menopausal women. Filamentary keratitis or erosion of the conjunctival and corneal epithelium may be caused by these disorders. Sensation of the presence of a foreign body in the eye and burning of the eyes may occur.
Sterile solutions that are intended for instillation into the eye. It does not include solutions for cleaning eyeglasses or CONTACT LENS SOLUTIONS.
Single layer of large flattened cells covering the surface of the cornea.
Measurement of distances or movements by means of the phenomena caused by the interference of two rays of light (optical interferometry) or of sound (acoustic interferometry).
Diseases affecting the eye.
The mucous membrane that covers the posterior surface of the eyelids and the anterior pericorneal surface of the eyeball.
The dioptric adjustment of the EYE (to attain maximal sharpness of retinal imagery for an object of regard) referring to the ability, to the mechanism, or to the process. Ocular accommodation is the effecting of refractive changes by changes in the shape of the CRYSTALLINE LENS. Loosely, it refers to ocular adjustments for VISION, OCULAR at various distances. (Cline et al., Dictionary of Visual Science, 4th ed)
Acrylic acids or acrylates which are substituted in the C-2 position with a methyl group.
Specific alloys not less than 85% chromium and nickel or cobalt, with traces of either nickel or cobalt, molybdenum, and other substances. They are used in partial dentures, orthopedic implants, etc.
Identification of those persons (or animals) who have had such an association with an infected person, animal, or contaminated environment as to have had the opportunity to acquire the infection. Contact tracing is a generally accepted method for the control of sexually transmitted diseases.
Characteristics or attributes of the outer boundaries of objects, including molecules.
The removal of a cataractous CRYSTALLINE LENS from the eye.
'Eye proteins' are structural or functional proteins, such as crystallins, opsins, and collagens, located in various parts of the eye, including the cornea, lens, retina, and aqueous humor, that contribute to maintaining transparency, refractive power, phototransduction, and overall integrity of the visual system.
Partial or total replacement of the CORNEA from one human or animal to another.
Infection with any of various amebae. It is an asymptomatic carrier state in most individuals, but diseases ranging from chronic, mild diarrhea to fulminant dysentery may occur.
Methods of creating machines and devices.
A type of acute or chronic skin reaction in which sensitivity is manifested by reactivity to materials or substances coming in contact with the skin. It may involve allergic or non-allergic mechanisms.
Dissolution of bone that particularly involves the removal or loss of calcium.
Measurement of the blood pressure of the retinal vessels. It is used also for the determination of the near point of convergence (CONVERGENCE, OCULAR). (From Cline, et al., Dictionary of Visual Science, 4th ed)

Visual outcome after contact lens and intraocular lens correction of neonatal monocular aphakia in monkeys. (1/53)

PURPOSE: A monkey model was used to evaluate intraocular lenses (IOLs) and extended-wear contact lenses (EWCLs) for the optical treatment of infantile aphakia in humans. Specifically, the relative effectiveness of EWCLs used alone and IOLs used in combination with EWCLs in preventing amblyopia was assessed. METHODS: A total of 33 rhesus monkeys was studied in this project, 24 assigned to experimental treatment groups and 9 to normal controls. Contact lenses made from a diffusing material or dyed opaque were placed on one eye at birth to simulate an infantile cataract. A unilateral lensectomy was then performed on the same eye within 2.5 weeks after birth. In 15 monkeys this was combined with implantation of an IOL. The eyes were left aphakic in the remaining 9 animals. EWCLs were used to adjust the optical correction of both aphakic and pseudophakic eyes to a near point (3-5 D). Opaque lenses were used to maintain daily part-time (approximately 70%) occlusion of the fellow eye. The primary outcome measure was grating acuity assessed with behavioral methods. Some animals were also assessed for acuity with sweep visually evoked potentials (VEPs) and for optotype acuity (Landolt C) with behavioral methods. RESULTS: Two of the animals with IOLs developed complications in the eye that precluded completion of the behavioral assessment protocol. Only behavioral outcomes obtained before or in the absence of surgical complications are presented. There was a developmental delay in the maturation of grating acuity in both eyes of both treatment groups. Normal adult levels of grating acuity were eventually achieved in the group treated with IOLs combined with EWCLs. Grating acuity was significantly poorer than normal in aphakic eyes treated only with EWCLs. Comparison of the two treatment groups revealed that pseudophakic eyes treated with multifocal IOLs had significantly better gating acuity than aphakic eyes. Assessments of optotype acuity and sweep VEP acuity revealed amblyopic deficits in both pseudophakic and aphakic eyes. CONCLUSIONS: Given an absence of serious postoperative complications, neonatal correction of aphakia with IOLs combined with EWCLs can lead to normal grating acuity in a primate model. Correction with EWCLs alone was not sufficient to produce normal grating acuity. Multifocal IOL treatments combined with EWCL provided a significantly better outcome than EWCL methods alone. However, neither IOL nor EWCL methods were able to prevent amblyopia as evaluated using behavioral testing with optotypes or with sweep VEPs.  (+info)

Extended wear contact lens related bacterial keratitis. (2/53)

AIMS: To report the clinical findings and visual outcome of patients with extended wear contact lens (EWCL) related bacterial keratitis. METHODS: 11 cases with EWCL related bacterial keratitis were included. Corneal scrapings were obtained for cytology and cultures. RESULTS: Nine patients had unilateral bacterial keratitis and two patients showed bilateral involvement. Corneal scrapings revealed Pseudomonas aeruginosa in seven patients, Staphylococcus aureus coagulase positive in one patient, and Staphylococcus epidermidis in three patients. CONCLUSION: EWCLs may be associated with bacterial keratitis and may result in visual loss. Dispensing contact lenses by optometrists should be performed in consultation with ophthalmologists.  (+info)

Short term wear of high Dk soft contact lenses does not alter corneal epithelial cell size or viability. (3/53)

BACKGROUND/AIMS: Current contact lenses (CLs) when worn on an extended wear basis cause corneal epithelial alterations. The aim of this study was to evaluate changes in corneal epithelial cell morphology and physiology following short term (3 months) wear of highly oxygen permeable CLs and to compare this with disposable CLs. METHODS: Subjects were wearers of highly oxygen permeable CLs (n=11, wearing CLs on a 30 night schedule), disposable CL users (n=6, wearing CLs on a 6 night schedule), and non-CL wearers (n=20). Mean CL wear experience was 3 months. Epithelial cells were harvested using corneal cytology and were stained using acridine orange and ethidium bromide. Epithelial cell size and viability were determined. RESULTS: The majority of epithelial cells recovered were non-viable (71%), and the mean longest cell diameter was 38 (SD 8) microm. Disposable CLs caused an increase in cell size (42 (7) microm) compared with both non-wear (39 (7) microm, p=0.01) and wear of highly oxygen permeable CLs (37 (10) microm, p=0.0049). There was no difference in cell viability between groups. CONCLUSIONS: Extended wear of disposable CLs caused an 8% increase in cell diameter in harvested corneal epithelial cells following 3 months of CL wear. Cells harvested following 3 months' wear of highly oxygen permeable CLs were indistinguishable from those recovered from non-CL wearers.  (+info)

Combined phototherapeutic keratectomy and therapeutic contact lens for recurrent erosions in bullous keratopathy. (4/53)

AIMS: To evaluate the therapeutic effects of excimer laser phototherapeutic keratectomy (PTK) combined with therapeutic contact lens for painful recurrent corneal erosions (RCE) secondary to bullous keratopathy (BK) not suitable for penetrating keratoplasty. METHODS: Excimer laser PTK was performed prospectively in eight eyes with painful RCE due to BK visually expecting no benefit from penetrating keratoplasty. After mechanical removal of the epithelium, the corneas were ablated with 50 pulses in the central 6.5 mm zone (ablation rate 0.25 microm per pulse) and another 200 pulses for polishing the periphery. After PTK, therapeutic contact lenses were applied for 3 months. The mean follow up period after PTK was 10.9 months (ranging from 6 to 15 months). RESULTS: All patients experienced relief of their pain symptoms after the epithelium healed. Only one patient complained of occasional stinging pain with intermittent recurrence of small bullae. He refused a second treatment because the pain was much less than that before the surgery and quite tolerable. No infection or other complications were noted. CONCLUSION: PTK with deeper ablation and adjunctive therapeutic contact lens is an easy to perform and effective treatment with less recurrence rate for patients with BK and poor visual potential.  (+info)

Predicting extended wear complications from overnight corneal swelling. (5/53)

PURPOSE: To examine the hypothesis that the corneal overnight swelling response (ONSR) is a predictor of ocular complications in contact lens extended wear (EW). METHODS: The Berkeley Contact Lens Extended Wear Study (CLEWS) was a randomized, concurrently controlled clinical trial in which more than 200 subjects in EW with rigid gas-permeable (RGP) lenses were observed for 1 year. After adapting to EW, subjects were randomized to either medium or high oxygen-permeable (Dk) RGP lenses and underwent clinical assessments, keratometry, and corneal pachometry at 3-month intervals. RESULTS: The ONSR was directly related to lens Dk (P = 0.01) and exhibited substantial variability across subjects. The probability of remaining free of complications over time was not significantly lower for subjects with a mild ONSR compared with those with greater edema (P = 0.84). The risk of development of keratopathy was not significantly related to the ONSR (relative risk = 1.00). CONCLUSIONS: The corneal ONSR is not a good predictor of ocular complications in 1 year of RGP EW. Lenses that cause little or no corneal edema are not necessarily safer for overnight wear.  (+info)

Impact of rigid gas-permeable contact lens extended wear on corneal epithelial barrier function. (6/53)

PURPOSE: To measure the effect of hypoxia and eye closure on epithelial permeability to fluorescein (P(dc)) during rigid lens extended wear (EW). METHODS: Central corneal thickness (CT) and P(dc) were measured in 42 subjects with an optical pachometer and automated scanning fluorophotometer, respectively. All subjects had been successfully wearing rigid gas-permeable (RGP) lenses on a 6-night EW regimen, and each individual was randomized to wear either medium- or high-oxygen-permeable (Dk) RGP lenses (two types of siloxane-fluorocarbon polymer lenses with Dk of 49 and 92). CT and P(dc) measurements were performed at an afternoon visit (baseline) and were repeated in the morning after 8 hours of overnight wear. Subjects slept with a patch over the right eye. The patch was not removed until immediately before the morning measurement. RESULTS: The mean overnight swelling response for subjects in the medium-Dk group was greater than that in the high-Dk group. Results of a paired t-test indicate that the eye wearing the medium-Dk lens with a patch overnight had a significant increase in epithelial permeability. Results of mixed-effect models suggest that eye closure and lens-induced hypoxia are significant factors in altering P(dc). CONCLUSIONS: The results indicate that corneal epithelial permeability increases with hypoxic dose and that epithelial barrier function is impaired by overnight rigid lens wear.  (+info)

Patterns of mucin adherence to contact lenses. (7/53)

PURPOSE: Contact lens wear alters the preocular fluid through factors that include tear deposits on the lens. In the current study, lens-adherent material was extracted to assess whether contact lenses sample mucins from the preocular fluid. METHODS: Discarded extended-wear contact lenses were collected from patients with no ocular surface disease. Mucins were extracted in guanidine hydrochloride (GuHCl) with protease inhibitors. After the supernatant was removed, the extraction was repeated twice with the addition of 10 mM dithiothreitol, making a total of three extractions. Mucins were isolated by cesium chloride (CsCl) gradient centrifugation and size fractionated on Sepharose CL2B. Charge distribution was analyzed on ion-exchange chromatography with a lithium perchlorate (LiClO(4)) gradient. RESULTS: Contact lens-adherent mucins comprised soluble mucins and mucins that required solubilization by (repeated) dithiothreitol treatment. MUC1, MUC4, MUC2, and MUC5AC mucins eluted mainly at low buoyant densities in extractions from lenses worn long term without disinfection and at successively higher buoyant densities from monthly disposable contact lenses. Mucins with little negative charge, which were observed in all extractions, and very highly negatively charged species, present in the second and third extractions from contact lenses, had no equivalents in tissue-extracted mucins. CONCLUSIONS: Mucins adhering to contact lenses are altered forms of intracellular mucins. Different degrees of adherence of mucins to contact lenses may occur, either because of mucin characteristics or after mucin complexation with adherent materials. In the context of good contact lens hygiene, their presence may offer some protection from toxicants in the tear film, because mucins could function as acceptors for charged moieties such as free radicals.  (+info)

Vertical movement of epithelial basal cells toward the corneal surface during use of extended-wear contact lenses. (8/53)

PURPOSE: To study the effects of extended contact lens wear (EW) on the movement of basal epithelial cells toward the corneal surface. METHODS: Rabbits (n = 32) were injected with 5-bromo-2-deoxyuridine (BrdU) to label a group of proliferating basal epithelial cells, and, 24 hours later, one randomly chosen eye was fitted with a low- or medium-oxygen-transmissible (Dk/t) rigid gas permeable (RGP) contact lens, while the other eye served as the control (n = 28). Four rabbits were not fitted with any contact lens. Rabbits were euthanatized at different time points and the corneal epithelium was immunocytochemically stained for BrdU and/or Ki-67 and counterstained with propidium iodide or Syto 59. Corneal flatmount tissues were examined three dimensionally under a laser confocal microscope and the location of each BrdU-labeled cell in the corneal epithelium (basal or suprabasal) was determined. RESULTS: Four days after injection of BrdU, both low- (P < 0.001) and medium-Dk/t RGP (P < 0.001) lens groups showed significantly more BrdU-labeled cells in the basal cell layer than in the control eyes. Six days after injection of BrdU, a small percentage of BrdU-labeled cells (<0.5%) were Ki-67 positive. CONCLUSIONS: Within 6 days, the majority (80%) of BrdU-labeled basal cells became terminally differentiated and rarely divided secondarily in the central epithelium. Short-term use of low- and medium-Dk/t RGP EW contact lenses slows the normal movement of basal epithelial cells toward the surface in the central cornea. This is consistent with known EW-lens-induced decreases in corneal epithelial basal cell proliferation and surface cell exfoliation. Overall, the data suggest that EW lenses significantly inhibit the normal homeostatic turnover rate of the corneal epithelium.  (+info)

Extended-wear contact lenses are a type of contact lens that is designed to be worn continuously, including during sleep, for an extended period of time. These lenses are typically made from materials that allow more oxygen to reach the eye, reducing the risk of eye irritation and infection compared to traditional overnight wear of non-extended wear lenses.

Extended-wear contact lenses can be worn for up to 30 days or longer, depending on the specific lens material and the individual's tolerance. However, it is important to note that even extended-wear contacts come with some risks, including a higher risk of eye infections and corneal ulcers compared to daily wear lenses. Therefore, it is essential to follow the recommended wearing schedule and replacement schedule provided by an eye care professional, as well as to have regular eye exams to monitor the health of the eyes.

Contact lenses are thin, curved plastic or silicone hydrogel devices that are placed on the eye to correct vision, replace a missing or damaged cornea, or for cosmetic purposes. They rest on the surface of the eye, called the cornea, and conform to its shape. Contact lenses are designed to float on a thin layer of tears and move with each blink.

There are two main types of contact lenses: soft and rigid gas permeable (RGP). Soft contact lenses are made of flexible hydrophilic (water-absorbing) materials that allow oxygen to pass through the lens to the cornea. RGP lenses are made of harder, more oxygen-permeable materials.

Contact lenses can be used to correct various vision problems, including nearsightedness, farsightedness, astigmatism, and presbyopia. They come in different shapes, sizes, and powers to suit individual needs and preferences. Proper care, handling, and regular check-ups with an eye care professional are essential for maintaining good eye health and preventing complications associated with contact lens wear.

Hydrophilic contact lenses are a type of contact lens that is designed to absorb and retain water. These lenses are made from materials that have an affinity for water, which helps them to remain moist and comfortable on the eye. The water content of hydrophilic contact lenses can vary, but typically ranges from 30-80% by weight.

Hydrophilic contact lenses are often used to correct refractive errors such as myopia (nearsightedness), hyperopia (farsightedness), and astigmatism. They can be made in a variety of materials, including soft hydrogel and silicone hydrogel.

One advantage of hydrophilic contact lenses is that they tend to be more comfortable to wear than other types of contacts, as they retain moisture and conform closely to the shape of the eye. However, they may also be more prone to deposits and buildup, which can lead to protein accumulation and discomfort over time. Proper care and cleaning are essential to maintain the health of the eyes when wearing hydrophilic contact lenses.

Disposable equipment in a medical context refers to items that are designed to be used once and then discarded. These items are often patient-care products that come into contact with patients or bodily fluids, and are meant to help reduce the risk of infection transmission. Examples of disposable medical equipment include gloves, gowns, face masks, syringes, and bandages.

Disposable equipment is intended for single use only and should not be reused or cleaned for reuse. This helps ensure that the equipment remains sterile and free from potential contaminants that could cause harm to patients or healthcare workers. Proper disposal of these items is also important to prevent the spread of infection and maintain a safe and clean environment.

Contact lens solutions are a type of disinfecting and cleaning solution specifically designed for use with contact lenses. They typically contain a combination of chemicals, such as preservatives, disinfectants, and surfactants, that work together to clean, disinfect, and store contact lenses safely and effectively.

There are several types of contact lens solutions available, including:

1. Multipurpose solution: This type of solution is the most commonly used and can be used for cleaning, rinsing, disinfecting, and storing soft contact lenses. It contains a combination of ingredients that perform all these functions in one step.
2. Hydrogen peroxide solution: This type of solution contains hydrogen peroxide as the main active ingredient, which is a powerful disinfectant. However, it requires a special case called a neutralizer to convert the hydrogen peroxide into water and oxygen before using the lenses.
3. Saline solution: This type of solution is used only for rinsing and storing contact lenses and does not contain any disinfecting or cleaning agents. It is often used in combination with other solutions for a complete contact lens care routine.
4. Daily cleaner: This type of solution is used to remove protein buildup and other deposits from the surface of contact lenses. It should be used in conjunction with a multipurpose or hydrogen peroxide solution as part of a daily cleaning routine.

It's important to follow the manufacturer's instructions carefully when using contact lens solutions to ensure that they are used safely and effectively. Failure to do so could result in eye irritation, infection, or other complications.

Aphakia, postcataract is a medical condition that refers to the absence of the lens in the eye after cataract surgery. A cataract is a clouding of the natural lens inside the eye that can cause vision loss. During cataract surgery, the cloudy lens is removed and replaced with an artificial lens implant. However, if there is a complication during the procedure and the artificial lens is not placed in the eye or if it becomes dislocated after surgery, then the patient will develop aphakia, postcataract.

Patients with aphakia, postcataract have poor vision and may experience symptoms such as blurry vision, glare, and halos around lights. They are also at an increased risk of developing glaucoma and retinal detachment. To correct the vision in patients with aphakia, they can wear special contact lenses or glasses with high-powered lenses, or undergo a secondary surgical procedure to implant an artificial lens in the eye.

Keratitis is a medical condition that refers to inflammation of the cornea, which is the clear, dome-shaped surface at the front of the eye. The cornea plays an essential role in focusing vision, and any damage or infection can cause significant visual impairment. Keratitis can result from various causes, including bacterial, viral, fungal, or parasitic infections, as well as trauma, allergies, or underlying medical conditions such as dry eye syndrome. Symptoms of keratitis may include redness, pain, tearing, sensitivity to light, blurred vision, and a feeling of something foreign in the eye. Treatment for keratitis depends on the underlying cause but typically includes antibiotics, antivirals, or anti-fungal medications, as well as measures to alleviate symptoms and promote healing.

Corneal edema is a medical condition characterized by the accumulation of fluid in the cornea, which is the clear, dome-shaped surface at the front of the eye. This buildup of fluid causes the cornea to swell and thicken, resulting in blurry or distorted vision. Corneal edema can be caused by various factors, including eye injuries, certain medications, eye surgeries, and diseases that affect the eye's ability to pump fluids out of the cornea. In some cases, corneal edema may resolve on its own or with treatment, but in severe cases, it may require a corneal transplant.

Corneal diseases are a group of disorders that affect the cornea, which is the clear, dome-shaped surface at the front of the eye. The cornea plays an important role in focusing vision, and any damage or disease can cause significant visual impairment or loss. Some common types of corneal diseases include:

1. Keratoconus: A progressive disorder in which the cornea thins and bulges outward into a cone shape, causing distorted vision.
2. Fuchs' dystrophy: A genetic disorder that affects the inner layer of the cornea called the endothelium, leading to swelling, cloudiness, and decreased vision.
3. Dry eye syndrome: A condition in which the eyes do not produce enough tears or the tears evaporate too quickly, causing discomfort, redness, and blurred vision.
4. Corneal ulcers: Open sores on the cornea that can be caused by infection, trauma, or other factors.
5. Herpes simplex keratitis: A viral infection of the cornea that can cause recurrent episodes of inflammation, scarring, and vision loss.
6. Corneal dystrophies: Inherited disorders that affect the structure and clarity of the cornea, leading to visual impairment or blindness.
7. Bullous keratopathy: A condition in which the endothelium fails to pump fluid out of the cornea, causing it to swell and form blisters.
8. Corneal trauma: Injury to the cornea caused by foreign objects, chemicals, or other factors that can lead to scarring, infection, and vision loss.

Treatment for corneal diseases varies depending on the specific condition and severity of the disease. Options may include eyedrops, medications, laser surgery, corneal transplantation, or other treatments.

Tooth wear is the progressive loss of tooth structure that can occur as a result of various factors. According to the medical definition, it refers to the wearing down, rubbing away, or grinding off of the hard tissues of the teeth (enamel and dentin) due to mechanical forces or chemical processes.

There are three primary types of tooth wear:

1. Abrasion: This is the loss of tooth structure caused by friction from external sources, such as incorrect brushing techniques, bite appliances, or habits like nail-biting and pipe smoking.
2. Attrition: This type of tooth wear results from the natural wearing down of teeth due to occlusal forces during biting, chewing, and grinding. However, excessive attrition can occur due to bruxism (teeth grinding) or clenching.
3. Erosion: Chemical processes, such as acid attacks from dietary sources (e.g., citrus fruits, sodas, and sports drinks) or gastric reflux, cause the loss of tooth structure in this type of tooth wear. The enamel dissolves when exposed to low pH levels, leaving the dentin underneath vulnerable to further damage.

Professional dental examination and treatment may be necessary to address significant tooth wear and prevent further progression, which can lead to sensitivity, pain, and functional or aesthetic issues.

Silicones are not a medical term, but they are commonly used in the medical field, particularly in medical devices and healthcare products. Silicones are synthetic polymers made up of repeating units of siloxane, which is a chain of alternating silicon and oxygen atoms. They can exist in various forms such as oils, gels, rubbers, and resins.

In the medical context, silicones are often used for their unique properties, including:

1. Biocompatibility - Silicones have a low risk of causing an adverse reaction when they come into contact with living tissue.
2. Inertness - They do not react chemically with other substances, making them suitable for use in medical devices that need to remain stable over time.
3. Temperature resistance - Silicones can maintain their flexibility and elasticity even under extreme temperature conditions.
4. Gas permeability - Some silicone materials allow gases like oxygen and water vapor to pass through, which is useful in applications where maintaining a moist environment is essential.
5. Durability - Silicones have excellent resistance to aging, weathering, and environmental factors, ensuring long-lasting performance.

Examples of medical applications for silicones include:

1. Breast implants
2. Contact lenses
3. Catheters
4. Artificial joints and tendons
5. Bandages and wound dressings
6. Drug delivery systems
7. Medical adhesives
8. Infant care products (nipples, pacifiers)

Acanthamoeba keratitis is a rare but serious infection of the cornea, which is the clear outer layer at the front of the eye. It's caused by a microscopic organism called Acanthamoeba, which is commonly found in water and soil.

The infection typically occurs in people who wear contact lenses, particularly those who do not clean and disinfect their lenses properly or who swim or shower while wearing their contacts. It can cause pain, redness, blurry vision, sensitivity to light, and a feeling like there's something in your eye.

If left untreated, Acanthamoeba keratitis can lead to serious complications, including corneal scarring, loss of vision, or even blindness. Treatment typically involves the use of specialized antimicrobial drops and sometimes requires a corneal transplant in severe cases. Prevention measures include proper contact lens hygiene, avoiding swimming or showering while wearing contacts, and regularly replacing contact lens storage cases.

In the context of medical terminology, "lenses" generally refers to optical lenses used in various medical devices and instruments. These lenses are typically made of glass or plastic and are designed to refract (bend) light in specific ways to help magnify, focus, or redirect images. Here are some examples:

1. In ophthalmology and optometry, lenses are used in eyeglasses, contact lenses, and ophthalmic instruments to correct vision problems like myopia (nearsightedness), hypermetropia (farsightedness), astigmatism, or presbyopia.
2. In surgical microscopes, lenses are used to provide a magnified and clear view of the operating field during microsurgical procedures like ophthalmic, neurosurgical, or ENT (Ear, Nose, Throat) surgeries.
3. In endoscopes and laparoscopes, lenses are used to transmit light and images from inside the body during minimally invasive surgical procedures.
4. In ophthalmic diagnostic instruments like slit lamps, lenses are used to examine various structures of the eye in detail.

In summary, "lenses" in medical terminology refer to optical components that help manipulate light to aid in diagnosis, treatment, or visual correction.

The cornea is the clear, dome-shaped surface at the front of the eye. It plays a crucial role in focusing vision. The cornea protects the eye from harmful particles and microorganisms, and it also serves as a barrier against UV light. Its transparency allows light to pass through and get focused onto the retina. The cornea does not contain blood vessels, so it relies on tears and the fluid inside the eye (aqueous humor) for nutrition and oxygen. Any damage or disease that affects its clarity and shape can significantly impact vision and potentially lead to blindness if left untreated.

Acanthamoeba is a genus of free-living, ubiquitous amoebae found in various environments such as soil, water, and air. These microorganisms have a characteristic morphology with thin, flexible pseudopods and large, rounded cells that contain endospores. They are known to cause two major types of infections in humans: Acanthamoeba keratitis, an often painful and potentially sight-threatening eye infection affecting the cornea; and granulomatous amoebic encephalitis (GAE), a rare but severe central nervous system infection primarily impacting individuals with weakened immune systems.

Acanthamoeba keratitis typically occurs through contact lens wearers accidentally introducing the organism into their eyes, often via contaminated water sources or inadequately disinfected contact lenses and solutions. Symptoms include eye pain, redness, sensitivity to light, tearing, and blurred vision. Early diagnosis and treatment are crucial for preventing severe complications and potential blindness.

Granulomatous amoebic encephalitis is an opportunistic infection that affects people with compromised immune systems, such as those with HIV/AIDS, cancer, or organ transplant recipients. The infection spreads hematogenously (through the bloodstream) to the central nervous system, where it causes inflammation and damage to brain tissue. Symptoms include headache, fever, stiff neck, seizures, altered mental status, and focal neurological deficits. GAE is associated with high mortality rates due to its severity and the challenges in diagnosing and treating the infection effectively.

Prevention strategies for Acanthamoeba infections include maintaining good hygiene practices, regularly replacing contact lenses and storage cases, using sterile saline solution or disposable contact lenses, and avoiding swimming or showering while wearing contact lenses. Early detection and appropriate medical intervention are essential for managing these infections and improving patient outcomes.

A corneal ulcer is a medical condition that affects the eye, specifically the cornea. It is characterized by an open sore or lesion on the surface of the cornea, which can be caused by various factors such as bacterial or fungal infections, viruses, or injury to the eye.

The cornea is a transparent tissue that covers the front part of the eye and protects it from harmful particles, bacteria, and other foreign substances. When the cornea becomes damaged or infected, it can lead to the development of an ulcer. Symptoms of a corneal ulcer may include pain, redness, tearing, sensitivity to light, blurred vision, and a white spot on the surface of the eye.

Corneal ulcers require prompt medical attention to prevent further damage to the eye and potential loss of vision. Treatment typically involves antibiotics or antifungal medications to eliminate the infection, as well as pain management and measures to protect the eye while it heals. In severe cases, surgery may be necessary to repair the damage to the cornea.

In medical terms, "tears" are a clear, salty liquid that is produced by the tear glands (lacrimal glands) in our eyes. They serve to keep the eyes moist, protect against dust and other foreign particles, and help to provide clear vision by maintaining a smooth surface on the front of the eye. Tears consist of water, oil, and mucus, which help to prevent evaporation and ensure that the tears spread evenly across the surface of the eye. Emotional or reflexive responses, such as crying or yawning, can also stimulate the production of tears.

Dental restoration wear refers to the progressive loss of structure and function of a dental restoration, such as a filling or crown, due to wear and tear over time. This can be caused by factors such as chewing, grinding, or clenching of teeth, as well as chemical dissolution from acidic foods and drinks. The wear can lead to changes in the shape and fit of the restoration, which may result in discomfort, sensitivity, or even failure of the restoration. Regular dental check-ups are important for monitoring dental restorations and addressing any issues related to wear before they become more serious.

Prosthesis fitting is the process of selecting, designing, fabricating, and fitting a prosthetic device to replace a part of an individual's body that is missing due to congenital absence, illness, injury, or amputation. The primary goal of prosthesis fitting is to restore the person's physical function, mobility, and independence, as well as improve their overall quality of life.

The process typically involves several steps:

1. Assessment: A thorough evaluation of the patient's medical history, physical condition, and functional needs is conducted to determine the most appropriate type of prosthesis. This may include measurements, castings, or digital scans of the residual limb.

2. Design: Based on the assessment, a customized design plan is created for the prosthetic device, taking into account factors such as the patient's lifestyle, occupation, and personal preferences.

3. Fabrication: The prosthesis is manufactured using various materials, components, and techniques to meet the specific requirements of the patient. This may involve the use of 3D printing, computer-aided design (CAD), or traditional handcrafting methods.

4. Fitting: Once the prosthesis is fabricated, it is carefully fitted to the patient's residual limb, ensuring optimal comfort, alignment, and stability. Adjustments may be made as needed to achieve the best fit and function.

5. Training: The patient receives training on how to use and care for their new prosthetic device, including exercises to strengthen the residual limb and improve overall mobility. Follow-up appointments are scheduled to monitor progress, make any necessary adjustments, and provide ongoing support.

Keratoconus is a degenerative non-inflammatory disorder of the eye, primarily affecting the cornea. It is characterized by a progressive thinning and steepening of the central or paracentral cornea, causing it to assume a conical shape. This results in irregular astigmatism, myopia, and scattering of light leading to blurred vision, visual distortions, and sensitivity to glare. The exact cause of keratoconus is unknown, but it may be associated with genetics, eye rubbing, and certain medical conditions. It typically starts in the teenage years and progresses into the third or fourth decade of life. Treatment options include glasses, contact lenses, cross-linking, and corneal transplantation in advanced cases.

Intraocular lenses (IOLs) are artificial lens implants that are placed inside the eye during ophthalmic surgery, such as cataract removal. These lenses are designed to replace the natural lens of the eye that has become clouded or damaged, thereby restoring vision impairment caused by cataracts or other conditions.

There are several types of intraocular lenses available, including monofocal, multifocal, toric, and accommodative lenses. Monofocal IOLs provide clear vision at a single fixed distance, while multifocal IOLs offer clear vision at multiple distances. Toric IOLs are designed to correct astigmatism, and accommodative IOLs can change shape and position within the eye to allow for a range of vision.

The selection of the appropriate type of intraocular lens depends on various factors, including the patient's individual visual needs, lifestyle, and ocular health. The implantation procedure is typically performed on an outpatient basis and involves minimal discomfort or recovery time. Overall, intraocular lenses have become a safe and effective treatment option for patients with vision impairment due to cataracts or other eye conditions.

Aphakia is a medical condition that refers to the absence of the lens in the eye. This can occur naturally, but it's most commonly the result of surgery to remove a cataract, a cloudy lens that can cause vision loss. In some cases, the lens may not be successfully removed or may be accidentally lost during surgery, leading to aphakia. People with aphakia typically have significant vision problems and may require corrective measures such as glasses, contact lenses, or an intraocular lens implant to improve their vision.

I'm sorry for any confusion, but "Polyethylene" is not a medical term. It is a type of synthetic plastic that is commonly used in various industrial and consumer products. Medical definitions typically refer to substances or conditions related to human health, treatment, or disease processes. If you have any questions related to medical terminology or concepts, I'd be happy to help!

Corneal topography is a non-invasive medical imaging technique used to create a detailed map of the surface curvature of the cornea, which is the clear, dome-shaped surface at the front of the eye. This procedure provides valuable information about the shape and condition of the cornea, helping eye care professionals assess various eye conditions such as astigmatism, keratoconus, and other corneal abnormalities. It can also be used in contact lens fitting, refractive surgery planning, and post-surgical evaluation.

Bacterial eye infections, also known as bacterial conjunctivitis or bacterial keratitis, are caused by the invasion of bacteria into the eye. The most common types of bacteria that cause these infections include Staphylococcus aureus, Streptococcus pneumoniae, and Haemophilus influenzae.

Bacterial conjunctivitis is an inflammation of the conjunctiva, the thin membrane that covers the white part of the eye and the inner surface of the eyelids. Symptoms include redness, swelling, pain, discharge, and a gritty feeling in the eye. Bacterial keratitis is an infection of the cornea, the clear front part of the eye. Symptoms include severe pain, sensitivity to light, tearing, and decreased vision.

Bacterial eye infections are typically treated with antibiotic eye drops or ointments. It is important to seek medical attention promptly if you suspect a bacterial eye infection, as untreated infections can lead to serious complications such as corneal ulcers and vision loss. Preventive measures include good hygiene practices, such as washing your hands frequently and avoiding touching or rubbing your eyes.

A hydrogel is a biomaterial that is composed of a three-dimensional network of crosslinked polymers, which are able to absorb and retain a significant amount of water or biological fluids while maintaining their structure. Hydrogels are similar to natural tissues in their water content, making them suitable for various medical applications such as contact lenses, wound dressings, drug delivery systems, tissue engineering, and regenerative medicine.

Hydrogels can be synthesized from a variety of materials, including synthetic polymers like polyethylene glycol (PEG) or natural polymers like collagen, hyaluronic acid, or chitosan. The properties of hydrogels, such as their mechanical strength, degradation rate, and biocompatibility, can be tailored to specific applications by adjusting the type and degree of crosslinking, the molecular weight of the polymers, and the addition of functional groups or drugs.

Hydrogels have shown great potential in medical research and clinical practice due to their ability to mimic the natural environment of cells and tissues, provide sustained drug release, and promote tissue regeneration.

A cataract is a clouding of the natural lens in the eye that affects vision. This clouding can cause vision to become blurry, faded, or dim, making it difficult to see clearly. Cataracts are a common age-related condition, but they can also be caused by injury, disease, or medication use. In most cases, cataracts develop gradually over time and can be treated with surgery to remove the cloudy lens and replace it with an artificial one.

Ocular refraction is a medical term that refers to the bending of light as it passes through the optical media of the eye, including the cornea and lens. This process allows the eye to focus light onto the retina, creating a clear image. The refractive power of the eye is determined by the curvature and transparency of these structures.

In a normal eye, light rays are bent or refracted in such a way that they converge at a single point on the retina, producing a sharp and focused image. However, if the curvature of the cornea or lens is too steep or too flat, the light rays may not converge properly, resulting in a refractive error such as myopia (nearsightedness), hyperopia (farsightedness), or astigmatism.

Ocular refraction can be measured using a variety of techniques, including retinoscopy, automated refraction, and subjective refraction. These measurements are used to determine the appropriate prescription for corrective lenses such as eyeglasses or contact lenses. In some cases, ocular refractive errors may be corrected surgically through procedures such as LASIK or PRK.

The crystalline lens in the eye is composed of three main parts: the capsule, the cortex, and the nucleus. The lens cortex is the outer layer of the lens, located between the capsule and the nucleus. It is made up of proteins and water, and its primary function is to help refract (bend) light rays as they pass through the eye, contributing to the focusing power of the eye.

The cortex is more flexible than the central nucleus, allowing it to change shape and adjust the focus of the eye for different distances. However, with age, the lens cortex can become less elastic, leading to presbyopia, a common age-related condition that affects the ability to focus on close objects. Additionally, changes in the lens cortex have been associated with cataracts, a clouding of the lens that can impair vision.

The crystalline lens of the eye is covered by a transparent, elastic capsule known as the lens capsule. This capsule is made up of collagen and forms the continuous outer layer of the lens. It is highly resistant to both physical and chemical insults, which allows it to protect the lens fibers within. The lens capsule is important for maintaining the shape and transparency of the lens, which are essential for proper focusing of light onto the retina.

Eyeglasses are a medical device used to correct vision problems. Also known as spectacles, they consist of frames that hold one or more lenses through which a person looks to see clearly. The lenses may be made of glass or plastic and are designed to compensate for various visual impairments such as nearsightedness, farsightedness, astigmatism, or presbyopia. Eyeglasses can be custom-made to fit an individual's face and prescription, and they come in a variety of styles, colors, and materials. Some people wear eyeglasses all the time, while others may only need to wear them for certain activities such as reading or driving.

Myopia, also known as nearsightedness, is a common refractive error of the eye. It occurs when the eye is either too long or the cornea (the clear front part of the eye) is too curved. As a result, light rays focus in front of the retina instead of directly on it, causing distant objects to appear blurry while close objects remain clear.

Myopia typically develops during childhood and can progress gradually or rapidly until early adulthood. It can be corrected with glasses, contact lenses, or refractive surgery such as LASIK. Regular eye examinations are essential for people with myopia to monitor any changes in their prescription and ensure proper correction.

While myopia is generally not a serious condition, high levels of nearsightedness can increase the risk of certain eye diseases, including cataracts, glaucoma, retinal detachment, and myopic degeneration. Therefore, it's crucial to manage myopia effectively and maintain regular follow-ups with an eye care professional.

The lens nucleus, also known as the crystalline lens nucleus, is the central part of the crystalline lens in the eye. The crystalline lens is a biconvex structure located behind the iris and pupil, which helps to refract (bend) light rays and focus them onto the retina.

The lens nucleus is composed of densely packed lens fibers that have lost their nuclei and cytoplasm during differentiation. It is surrounded by the lens cortex, which consists of younger lens fiber cells that are still metabolically active. The lens nucleus is relatively avascular and receives its nutrients through diffusion from the aqueous humor in the anterior chamber of the eye.

The lens nucleus plays an important role in the accommodation process, which allows the eye to focus on objects at different distances. During accommodation, the ciliary muscles contract and release tension on the lens zonules, allowing the lens to become thicker and increase its curvature. This results in a decrease in the focal length of the lens and enables the eye to focus on nearby objects. The lens nucleus is more rigid than the cortex and helps maintain the shape of the lens during accommodation.

Changes in the lens nucleus are associated with several age-related eye conditions, including cataracts and presbyopia. Cataracts occur when the lens becomes cloudy or opaque, leading to a decrease in vision clarity. Presbyopia is a condition that affects the ability to focus on near objects and is caused by a hardening of the lens nucleus and a loss of elasticity in the lens fibers.

I believe there may be some confusion in your question as Polyethylenes are not a medical term, but rather a category of synthetic polymers commonly used in various industrial and medical applications. Here's a brief overview:

Polyethylene (PE) is a type of thermoplastic polymer made from the monomer ethylene. It is a versatile material with numerous applications due to its chemical resistance, durability, and flexibility. There are several types of polyethylenes, including:

1. Low-density polyethylene (LDPE): This type has a lower density and more branching in its molecular structure, which results in less crystallinity. LDPE is known for its flexibility and is often used in packaging films, bags, and containers.
2. High-density polyethylene (HDPE): HDPE has a higher density and less branching, resulting in greater crystallinity. It is more rigid than LDPE and is commonly used in applications such as bottles, pipes, and containers.
3. Linear low-density polyethylene (LLDPE): This type combines the flexibility of LDPE with some of the strength and rigidity of HDPE. LLDPE has fewer branches than LDPE but more than HDPE. It is often used in film applications, such as stretch wrap and agricultural films.
4. Ultra-high molecular weight polyethylene (UHMWPE): UHMWPE has an extremely high molecular weight, resulting in exceptional wear resistance, impact strength, and chemical resistance. It is commonly used in medical applications, such as orthopedic implants and joint replacements, due to its biocompatibility and low friction coefficient.

While polyethylenes are not a medical term per se, they do have significant medical applications, particularly UHMWPE in orthopedic devices.

Disinfection is the process of eliminating or reducing harmful microorganisms from inanimate objects and surfaces through the use of chemicals, heat, or other methods. The goal of disinfection is to reduce the number of pathogens to a level that is considered safe for human health. Disinfection is an important step in preventing the spread of infectious diseases in healthcare settings, food processing facilities, and other environments where there is a risk of infection transmission.

It's important to note that disinfection is not the same as sterilization, which is the complete elimination of all microorganisms, including spores. Disinfection is generally less effective than sterilization but is often sufficient for most non-critical surfaces and objects. The choice between disinfection and sterilization depends on the level of risk associated with the item or surface being treated and the intended use of that item or surface.

Fluorophotometry is a medical diagnostic technique that measures the concentration of fluorescein dye in various tissues, particularly the eye. This technique utilizes a specialized instrument called a fluorophotometer which emits light at a specific wavelength that causes the fluorescein to emit light at a longer wavelength. The intensity of this emitted light is then measured and used to calculate the concentration of fluorescein in the tissue.

Fluorophotometry is often used in ophthalmology to assess the permeability of the blood-retinal barrier, which can be helpful in diagnosing and monitoring conditions such as diabetic retinopathy, age-related macular degeneration, and uveitis. It may also have applications in other medical fields for measuring the concentration of fluorescent markers in various tissues.

Hydrogels are defined in the medical and biomedical fields as cross-linked, hydrophilic polymer networks that have the ability to swell and retain a significant amount of water or biological fluids while maintaining their structure. They can be synthesized from natural, synthetic, or hybrid polymers.

Hydrogels are known for their biocompatibility, high water content, and soft consistency, which resemble natural tissues, making them suitable for various medical applications such as contact lenses, drug delivery systems, tissue engineering, wound dressing, and biosensors. The physical and chemical properties of hydrogels can be tailored to specific uses by adjusting the polymer composition, cross-linking density, and network structure.

Lens diseases refer to conditions that affect the lens of the eye, which is a transparent structure located behind the iris and pupil. The main function of the lens is to focus light onto the retina, enabling clear vision. Here are some examples of lens diseases:

1. Cataract: A cataract is a clouding of the lens that affects vision. It is a common age-related condition, but can also be caused by injury, disease, or medication.
2. Presbyopia: This is not strictly a "disease," but rather an age-related change in the lens that causes difficulty focusing on close objects. It typically becomes noticeable in people over the age of 40.
3. Lens dislocation: This occurs when the lens slips out of its normal position, usually due to trauma or a genetic disorder. It can cause vision problems and may require surgical intervention.
4. Lens opacity: This refers to any clouding or opacification of the lens that is not severe enough to be considered a cataract. It can cause visual symptoms such as glare or blurred vision.
5. Anterior subcapsular cataract: This is a type of cataract that forms in the front part of the lens, often as a result of injury or inflammation. It can cause significant visual impairment.
6. Posterior subcapsular cataract: This is another type of cataract that forms at the back of the lens, often as a result of diabetes or certain medications. It can also cause significant visual impairment.

Overall, lens diseases can have a significant impact on vision and quality of life, and may require medical intervention to manage or treat.

Visual acuity is a measure of the sharpness or clarity of vision. It is usually tested by reading an eye chart from a specific distance, such as 20 feet (6 meters). The standard eye chart used for this purpose is called the Snellen chart, which contains rows of letters that decrease in size as you read down the chart.

Visual acuity is typically expressed as a fraction, with the numerator representing the testing distance and the denominator indicating the smallest line of type that can be read clearly. For example, if a person can read the line on the eye chart that corresponds to a visual acuity of 20/20, it means they have normal vision at 20 feet. If their visual acuity is 20/40, it means they must be as close as 20 feet to see what someone with normal vision can see at 40 feet.

It's important to note that visual acuity is just one aspect of overall vision and does not necessarily reflect other important factors such as peripheral vision, depth perception, color vision, or contrast sensitivity.

Intraocular lens (IOL) implantation is a surgical procedure that involves placing a small artificial lens inside the eye to replace the natural lens that has been removed. This procedure is typically performed during cataract surgery, where the cloudy natural lens is removed and replaced with an IOL to restore clear vision.

During the procedure, a small incision is made in the eye, and the cloudy lens is broken up and removed using ultrasound waves or laser energy. Then, the folded IOL is inserted through the same incision and positioned in the correct place inside the eye. Once in place, the IOL unfolds and is secured into position.

There are several types of IOLs available, including monofocal, multifocal, toric, and accommodating lenses. Monofocal lenses provide clear vision at one distance, while multifocal lenses offer clear vision at multiple distances. Toric lenses correct astigmatism, and accommodating lenses can change shape to focus on objects at different distances.

Overall, intraocular lens implantation is a safe and effective procedure that can help restore clear vision in patients with cataracts or other eye conditions that require the removal of the natural lens.

Fusariosis is a rare but serious invasive fungal infection caused by the Fusarium species, a type of filamentous fungi that are commonly found in the environment, particularly in soil and plants. The infection can affect various organs and tissues, including the lungs, sinuses, skin, nails, and internal organs such as the brain, heart, and kidneys.

Fusariosis is often difficult to diagnose due to its nonspecific symptoms and the challenges of detecting the fungus in clinical samples. The infection can occur in people with weakened immune systems, such as those undergoing chemotherapy, organ transplantation, or treatment with immunosuppressive drugs.

The severity of fusariosis varies depending on the site of infection and the patient's underlying health status. In some cases, it can cause severe illness and even death, especially in patients with prolonged neutropenia (low white blood cell count) or other serious medical conditions. Treatment typically involves antifungal medications, such as voriconazole or amphotericin B, and sometimes surgical debridement of infected tissues.

Equipment contamination in a medical context refers to the presence of harmful microorganisms, such as bacteria, viruses, or fungi, on the surfaces of medical equipment or devices. This can occur during use, storage, or transportation of the equipment and can lead to the transmission of infections to patients, healthcare workers, or other individuals who come into contact with the contaminated equipment.

Equipment contamination can occur through various routes, including contact with contaminated body fluids, airborne particles, or environmental surfaces. To prevent equipment contamination and the resulting infection transmission, it is essential to follow strict infection control practices, such as regular cleaning and disinfection of equipment, use of personal protective equipment (PPE), and proper handling and storage of medical devices.

Presbyopia is a age-related eye condition, typically occurring after the age of 40, where the lens of the eye loses its flexibility and makes it difficult to focus on near objects. This results in blurred vision when reading, sewing or focusing on other close-up tasks. It's a natural part of the aging process and is not a disease. Corrective measures such as reading glasses, bifocals, multifocal lenses or contact lenses, or refractive surgery can help manage this condition.

Astigmatism is a common eye condition that occurs when the cornea or lens has an irregular shape, causing blurred or distorted vision. The cornea and lens are typically smooth and curved uniformly in all directions, allowing light to focus clearly on the retina. However, if the cornea or lens is not smoothly curved and has a steeper curve in one direction than the other, it causes light to focus unevenly on the retina, leading to astigmatism.

Astigmatism can cause blurred vision at all distances, as well as eye strain, headaches, and fatigue. It is often present from birth and can be hereditary, but it can also develop later in life due to eye injuries or surgery. Astigmatism can be corrected with glasses, contact lenses, or refractive surgery such as LASIK.

Polyhydroxyethyl Methacrylate (PHEMA) is not a medical term itself, but a chemical compound that is used in various medical and biomedical applications. Therefore, I will provide you with a chemical definition of PHEMA:

Polyhydroxyethyl Methacrylate (PHEMA) is a type of synthetic hydrogel, which is a cross-linked polymer network with the ability to absorb and retain significant amounts of water or biological fluids. It is made by polymerizing the methacrylate monomer, hydroxyethyl methacrylate (HEMA), in the presence of a crosslinking agent. The resulting PHEMA material has excellent biocompatibility, making it suitable for various medical applications such as contact lenses, drug delivery systems, artificial cartilage, and wound dressings.

Methyl Methacrylates (MMA) are a family of synthetic materials that are commonly used in the medical field, particularly in orthopedic and dental applications. Medically, MMA is often used as a bone cement to fix prosthetic implants, such as artificial hips or knees, into place during surgeries.

Methyl methacrylates consist of a type of acrylic resin that hardens when mixed with a liquid catalyst. This property allows it to be easily molded and shaped before it sets, making it ideal for use in surgical procedures where precise positioning is required. Once hardened, MMA forms a strong, stable bond with the bone, helping to secure the implant in place.

It's important to note that while MMA is widely used in medical applications, there have been concerns about its safety in certain situations. For example, some studies have suggested that high levels of methyl methacrylate fumes released during the setting process may be harmful to both patients and surgical staff. Therefore, appropriate precautions should be taken when using MMA-based products in medical settings.

Fungal eye infections, also known as fungal keratitis or ocular fungal infections, are caused by the invasion of fungi into the eye. The most common types of fungi that cause these infections include Fusarium, Aspergillus, and Candida. These infections can affect any part of the eye, including the cornea, conjunctiva, sclera, and vitreous humor.

Fungal eye infections often present with symptoms such as redness, pain, sensitivity to light, tearing, blurred vision, and discharge. In severe cases, they can lead to corneal ulcers, perforation of the eye, and even blindness if left untreated. Risk factors for fungal eye infections include trauma to the eye, contact lens wear, immunosuppression, and pre-existing eye conditions such as dry eye or previous eye surgery.

Diagnosis of fungal eye infections typically involves a thorough eye examination, including visual acuity testing, slit lamp examination, and sometimes corneal scrapings for microbiological culture and sensitivity testing. Treatment usually involves topical antifungal medications, such as natamycin or amphotericin B, and in some cases may require oral or intravenous antifungal therapy. In severe cases, surgical intervention may be necessary to remove infected tissue or repair any damage caused by the infection.

The corneal epithelium is the outermost layer of the cornea, which is the clear, dome-shaped surface at the front of the eye. It is a stratified squamous epithelium, consisting of several layers of flat, scale-like cells that are tightly packed together. The corneal epithelium serves as a barrier to protect the eye from microorganisms, dust, and other foreign particles. It also provides a smooth surface for the refraction of light, contributes to the maintenance of corneal transparency, and plays a role in the eye's sensitivity to touch and pain. The corneal epithelium is constantly being renewed through the process of cell division and shedding, with new cells produced by stem cells located at the limbus, the border between the cornea and the conjunctiva.

Crystallins are the major proteins found in the lens of the eye in vertebrates. They make up about 90% of the protein content in the lens and are responsible for maintaining the transparency and refractive properties of the lens, which are essential for clear vision. There are two main types of crystallins, alpha (α) and beta/gamma (β/γ), which are further divided into several subtypes. These proteins are highly stable and have a long half-life, which allows them to remain in the lens for an extended period of time. Mutations in crystallin genes have been associated with various eye disorders, including cataracts and certain types of glaucoma.

Prosthesis failure is a term used to describe a situation where a prosthetic device, such as an artificial joint or limb, has stopped functioning or failed to meet its intended purpose. This can be due to various reasons, including mechanical failure, infection, loosening of the device, or a reaction to the materials used in the prosthesis.

Mechanical failure can occur due to wear and tear, manufacturing defects, or improper use of the prosthetic device. Infection can also lead to prosthesis failure, particularly in cases where the prosthesis is implanted inside the body. The immune system may react to the presence of the foreign material, leading to inflammation and infection.

Loosening of the prosthesis can also cause it to fail over time, as the device becomes less stable and eventually stops working properly. Additionally, some people may have a reaction to the materials used in the prosthesis, leading to tissue damage or other complications that can result in prosthesis failure.

In general, prosthesis failure can lead to decreased mobility, pain, and the need for additional surgeries or treatments to correct the problem. It is important for individuals with prosthetic devices to follow their healthcare provider's instructions carefully to minimize the risk of prosthesis failure and ensure that the device continues to function properly over time.

Refractive errors are a group of vision conditions that include nearsightedness (myopia), farsightedness (hyperopia), astigmatism, and presbyopia. These conditions occur when the shape of the eye prevents light from focusing directly on the retina, causing blurred or distorted vision.

Myopia is a condition where distant objects appear blurry while close-up objects are clear. This occurs when the eye is too long or the cornea is too curved, causing light to focus in front of the retina instead of directly on it.

Hyperopia, on the other hand, is a condition where close-up objects appear blurry while distant objects are clear. This happens when the eye is too short or the cornea is not curved enough, causing light to focus behind the retina.

Astigmatism is a condition that causes blurred vision at all distances due to an irregularly shaped cornea or lens.

Presbyopia is a natural aging process that affects everyone as they get older, usually around the age of 40. It causes difficulty focusing on close-up objects and can be corrected with reading glasses, bifocals, or progressive lenses.

Refractive errors can be diagnosed through a comprehensive eye exam and are typically corrected with eyeglasses, contact lenses, or refractive surgery such as LASIK.

Eyelids are the thin folds of skin that cover and protect the front surface (cornea) of the eye when closed. They are composed of several layers, including the skin, muscle, connective tissue, and a mucous membrane called the conjunctiva. The upper and lower eyelids meet at the outer corner of the eye (lateral canthus) and the inner corner of the eye (medial canthus).

The main function of the eyelids is to protect the eye from foreign particles, light, and trauma. They also help to distribute tears evenly over the surface of the eye through blinking, which helps to keep the eye moist and healthy. Additionally, the eyelids play a role in facial expressions and non-verbal communication.

Orthokeratology, often referred to as "ortho-k," is a non-surgical procedure that uses specially designed contact lenses to temporarily reshape the cornea (the clear, dome-shaped surface at the front of the eye). The goal of orthokeratology is to flatten the cornea slightly so that it can properly focus light onto the retina and improve vision.

During an orthokeratology procedure, a patient wears specially fitted contact lenses while they sleep. These lenses gently reshape the cornea overnight, allowing the patient to see clearly during the day without needing glasses or contact lenses. The effects of orthokeratology are usually reversible and may wear off if the patient stops wearing the contact lenses regularly.

Orthokeratology is often used as an alternative to refractive surgery for people who want to correct their vision without undergoing a surgical procedure. It can be particularly useful for individuals with mild to moderate myopia (nearsightedness) and astigmatism, although it may also be used to treat other refractive errors.

It's important to note that orthokeratology is not a permanent solution for vision problems, and it does carry some risks, such as eye infections and corneal abrasions. As with any medical procedure, it's essential to consult with an eye care professional to determine whether orthokeratology is the right choice for you.

Eye infections, also known as ocular infections, are conditions characterized by the invasion and multiplication of pathogenic microorganisms in any part of the eye or its surrounding structures. These infections can affect various parts of the eye, including the conjunctiva (conjunctivitis), cornea (keratitis), eyelid (blepharitis), or the internal structures of the eye (endophthalmitis, uveitis). The symptoms may include redness, pain, discharge, itching, blurred vision, and sensitivity to light. The cause can be bacterial, viral, fungal, or parasitic, and the treatment typically involves antibiotics, antivirals, or antifungals, depending on the underlying cause.

Prosthesis design is a specialized field in medical device technology that involves creating and developing artificial substitutes to replace a missing body part, such as a limb, tooth, eye, or internal organ. The design process typically includes several stages: assessment of the patient's needs, selection of appropriate materials, creation of a prototype, testing and refinement, and final fabrication and fitting of the prosthesis.

The goal of prosthesis design is to create a device that functions as closely as possible to the natural body part it replaces, while also being comfortable, durable, and aesthetically pleasing for the patient. The design process may involve collaboration between medical professionals, engineers, and designers, and may take into account factors such as the patient's age, lifestyle, occupation, and overall health.

Prosthesis design can be highly complex, particularly for advanced devices such as robotic limbs or implantable organs. These devices often require sophisticated sensors, actuators, and control systems to mimic the natural functions of the body part they replace. As a result, prosthesis design is an active area of research and development in the medical field, with ongoing efforts to improve the functionality, comfort, and affordability of these devices for patients.

Lens subluxation, also known as lens dislocation or ectopia lentis, is a condition where the lens of the eye becomes partially or completely displaced from its normal position. The lens is held in place by tiny fibers called zonules, which can become weakened or broken due to various reasons such as genetic disorders (like Marfan syndrome, homocystinuria, and Weill-Marchesani syndrome), trauma, inflammation, or cataract surgery complications. This displacement can lead to symptoms like blurry vision, double vision, sensitivity to light, or the appearance of a shadow in the peripheral vision. In some cases, lens subluxation may not cause any noticeable symptoms and can be discovered during routine eye examinations. Treatment options depend on the severity and underlying cause of the subluxation and may include eyeglasses, contact lenses, or surgical intervention to remove and replace the displaced lens with an intraocular lens (IOL).

The corneal stroma, also known as the substantia propria, is the thickest layer of the cornea, which is the clear, dome-shaped surface at the front of the eye. The cornea plays a crucial role in focusing vision.

The corneal stroma makes up about 90% of the cornea's thickness and is composed of parallel bundles of collagen fibers that are arranged in regular, repeating patterns. These fibers give the cornea its strength and transparency. The corneal stroma also contains a small number of cells called keratocytes, which produce and maintain the collagen fibers.

Disorders that affect the corneal stroma can cause vision loss or other eye problems. For example, conditions such as keratoconus, in which the cornea becomes thin and bulges outward, can distort vision and make it difficult to see clearly. Other conditions, such as corneal scarring or infection, can also affect the corneal stroma and lead to vision loss or other eye problems.

Hyperopia, also known as farsightedness, is a refractive error in which the eye does not focus light directly on the retina when looking at a distant object. Instead, light is focused behind the retina, causing close-up objects to appear blurry. This condition usually results from the eyeball being too short or the cornea having too little curvature. It can be corrected with eyeglasses, contact lenses, or refractive surgery.

Disinfectants are antimicrobial agents that are applied to non-living objects to destroy or irreversibly inactivate microorganisms, but not necessarily their spores. They are different from sterilizers, which kill all forms of life, and from antiseptics, which are used on living tissue. Disinfectants work by damaging the cell wall or membrane of the microorganism, disrupting its metabolism, or interfering with its ability to reproduce. Examples of disinfectants include alcohol, bleach, hydrogen peroxide, and quaternary ammonium compounds. They are commonly used in hospitals, laboratories, and other settings where the elimination of microorganisms is important for infection control. It's important to use disinfectants according to the manufacturer's instructions, as improper use can reduce their effectiveness or even increase the risk of infection.

Silicone elastomers are a type of synthetic rubber made from silicone, which is a polymer composed primarily of silicon-oxygen bonds. They are known for their durability, flexibility, and resistance to heat, cold, and moisture. Silicone elastomers can be manufactured in various forms, including liquids, gels, and solids, and they are used in a wide range of medical applications such as:

1. Breast implants: Silicone elastomer shells filled with silicone gel are commonly used for breast augmentation and reconstruction.
2. Contact lenses: Some contact lenses are made from silicone elastomers due to their high oxygen permeability, which allows for better eye health.
3. Catheters: Silicone elastomer catheters are flexible and resistant to kinking, making them suitable for long-term use in various medical procedures.
4. Implantable drug delivery systems: Silicone elastomers can be used as a matrix for controlled release of drugs, allowing for sustained and targeted medication administration.
5. Medical adhesives: Silicone elastomer adhesives are biocompatible and can be used to attach medical devices to the skin or other tissues.
6. Sealants and coatings: Silicone elastomers can be used as sealants and coatings in medical devices to prevent leakage, improve durability, and reduce infection risk.

It is important to note that while silicone elastomers are generally considered safe for medical use, there have been concerns about the potential health risks associated with breast implants, such as capsular contracture, breast pain, and immune system reactions. However, these risks vary depending on the individual's health status and the specific type of silicone elastomer used.

The eye is the organ of sight, primarily responsible for detecting and focusing on visual stimuli. It is a complex structure composed of various parts that work together to enable vision. Here are some of the main components of the eye:

1. Cornea: The clear front part of the eye that refracts light entering the eye and protects the eye from harmful particles and microorganisms.
2. Iris: The colored part of the eye that controls the amount of light reaching the retina by adjusting the size of the pupil.
3. Pupil: The opening in the center of the iris that allows light to enter the eye.
4. Lens: A biconvex structure located behind the iris that further refracts light and focuses it onto the retina.
5. Retina: A layer of light-sensitive cells (rods and cones) at the back of the eye that convert light into electrical signals, which are then transmitted to the brain via the optic nerve.
6. Optic Nerve: The nerve that carries visual information from the retina to the brain.
7. Vitreous: A clear, gel-like substance that fills the space between the lens and the retina, providing structural support to the eye.
8. Conjunctiva: A thin, transparent membrane that covers the front of the eye and the inner surface of the eyelids.
9. Extraocular Muscles: Six muscles that control the movement of the eye, allowing for proper alignment and focus.

The eye is a remarkable organ that allows us to perceive and interact with our surroundings. Various medical specialties, such as ophthalmology and optometry, are dedicated to the diagnosis, treatment, and management of various eye conditions and diseases.

Hygiene is the science and practice of maintaining and promoting health and preventing disease through cleanliness in personal and public environments. It includes various measures such as handwashing, bathing, using clean clothes, cleaning and disinfecting surfaces, proper waste disposal, safe food handling, and managing water supplies to prevent the spread of infectious agents like bacteria, viruses, and parasites.

In a medical context, hygiene is crucial in healthcare settings to prevent healthcare-associated infections (HAIs) and ensure patient safety. Healthcare professionals are trained in infection control practices, including proper hand hygiene, use of personal protective equipment (PPE), environmental cleaning and disinfection, and safe injection practices.

Overall, maintaining good hygiene is essential for overall health and well-being, reducing the risk of illness and promoting a healthy lifestyle.

A hip prosthesis, also known as a total hip replacement, is a surgical implant designed to replace the damaged or diseased components of the human hip joint. The procedure involves replacing the femoral head (the ball at the top of the thigh bone) and the acetabulum (the socket in the pelvis) with artificial parts, typically made from materials such as metal, ceramic, or plastic.

The goal of a hip prosthesis is to relieve pain, improve joint mobility, and restore function, allowing patients to return to their normal activities and enjoy an improved quality of life. The procedure is most commonly performed in individuals with advanced osteoarthritis, rheumatoid arthritis, or other degenerative conditions that have caused significant damage to the hip joint.

There are several different types of hip prostheses available, each with its own unique design and set of benefits and risks. The choice of prosthesis will depend on a variety of factors, including the patient's age, activity level, overall health, and specific medical needs. In general, however, all hip prostheses are designed to provide a durable, long-lasting solution for patients suffering from debilitating joint pain and stiffness.

Dry eye syndrome, also known as keratoconjunctivitis sicca, is a condition characterized by insufficient lubrication and moisture of the eyes. This occurs when the tears produced by the eyes are not sufficient in quantity or quality to keep the eyes moist and comfortable. The medical definition of dry eye syndromes includes the following symptoms:

1. A gritty or sandy sensation in the eyes
2. Burning or stinging sensations
3. Redness and irritation
4. Blurred vision that improves with blinking
5. Light sensitivity
6. A feeling of something foreign in the eye
7. Stringy mucus in or around the eyes
8. Difficulty wearing contact lenses
9. Watery eyes, which may seem contradictory but can be a response to dryness
10. Eye fatigue and discomfort after prolonged screen time or reading

The causes of dry eye syndromes can include aging, hormonal changes, certain medical conditions (such as diabetes, rheumatoid arthritis, lupus, Sjogren's syndrome), medications (antihistamines, decongestants, antidepressants, birth control pills), environmental factors (dry air, wind, smoke, dust), and prolonged screen time or reading.

Treatment for dry eye syndromes depends on the severity of the condition and its underlying causes. It may include artificial tears, lifestyle changes, prescription medications, and in some cases, surgical procedures to improve tear production or drainage.

Ophthalmic solutions are sterile, single-use or multi-dose preparations in a liquid form that are intended for topical administration to the eye. These solutions can contain various types of medications, such as antibiotics, anti-inflammatory agents, antihistamines, or lubricants, which are used to treat or prevent ocular diseases and conditions.

The pH and osmolarity of ophthalmic solutions are carefully controlled to match the physiological environment of the eye and minimize any potential discomfort or irritation. The solutions may be packaged in various forms, including drops, sprays, or irrigations, depending on the intended use and administration route.

It is important to follow the instructions for use provided by a healthcare professional when administering ophthalmic solutions, as improper use can lead to eye injury or reduced effectiveness of the medication.

The endothelium of the cornea is the thin, innermost layer of cells that lines the inner surface of the cornea, which is the clear, dome-shaped structure at the front of the eye. This single layer of specialized cells is essential for maintaining the transparency and proper hydration of the cornea, allowing light to pass through it and focus on the retina.

The endothelial cells are hexagonal in shape and have tight junctions between them, creating a semi-permeable barrier that controls the movement of water and solutes between the corneal stroma (the middle layer of the cornea) and the anterior chamber (the space between the cornea and the iris). The endothelial cells actively pump excess fluid out of the cornea, maintaining a delicate balance of hydration that is critical for corneal clarity.

Damage to or dysfunction of the corneal endothelium can result in corneal edema (swelling), cloudiness, and loss of vision. Factors contributing to endothelial damage include aging, eye trauma, intraocular surgery, and certain diseases such as Fuchs' dystrophy and glaucoma.

Interferometry is not specifically a medical term, but it is used in certain medical fields such as ophthalmology and optics research. Here is a general definition:

Interferometry is a physical method that uses the interference of waves to measure the differences in phase between two or more waves. In other words, it's a technique that combines two or more light waves to create an interference pattern, which can then be analyzed to extract information about the properties of the light waves, such as their wavelength, amplitude, and phase.

In ophthalmology, interferometry is used in devices like wavefront sensors to measure the aberrations in the eye's optical system. By analyzing the interference pattern created by the light passing through the eye, these devices can provide detailed information about the shape and curvature of the cornea and lens, helping doctors to diagnose and treat various vision disorders.

In optics research, interferometry is used to study the properties of light waves and materials that interact with them. By analyzing the interference patterns created by light passing through different materials or devices, researchers can gain insights into their optical properties, such as their refractive index, thickness, and surface roughness.

Eye diseases are a range of conditions that affect the eye or visual system, causing damage to vision and, in some cases, leading to blindness. These diseases can be categorized into various types, including:

1. Refractive errors: These include myopia (nearsightedness), hyperopia (farsightedness), astigmatism, and presbyopia, which affect the way light is focused on the retina and can usually be corrected with glasses or contact lenses.
2. Cataracts: A clouding of the lens inside the eye that leads to blurry vision, glare, and decreased contrast sensitivity. Cataract surgery is the most common treatment for this condition.
3. Glaucoma: A group of diseases characterized by increased pressure in the eye, leading to damage to the optic nerve and potential blindness if left untreated. Treatment includes medications, laser therapy, or surgery.
4. Age-related macular degeneration (AMD): A progressive condition that affects the central part of the retina called the macula, causing blurry vision and, in advanced stages, loss of central vision. Treatment may include anti-VEGF injections, laser therapy, or nutritional supplements.
5. Diabetic retinopathy: A complication of diabetes that affects the blood vessels in the retina, leading to bleeding, leakage, and potential blindness if left untreated. Treatment includes laser therapy, anti-VEGF injections, or surgery.
6. Retinal detachment: A separation of the retina from its underlying tissue, which can lead to vision loss if not treated promptly with surgery.
7. Amblyopia (lazy eye): A condition where one eye does not develop normal vision, often due to a misalignment or refractive error in childhood. Treatment includes correcting the underlying problem and encouraging the use of the weaker eye through patching or other methods.
8. Strabismus (crossed eyes): A misalignment of the eyes that can lead to amblyopia if not treated promptly with surgery, glasses, or other methods.
9. Corneal diseases: Conditions that affect the transparent outer layer of the eye, such as keratoconus, Fuchs' dystrophy, and infectious keratitis, which can lead to vision loss if not treated promptly.
10. Uveitis: Inflammation of the middle layer of the eye, which can cause vision loss if not treated promptly with anti-inflammatory medications or surgery.

The conjunctiva is the mucous membrane that lines the inner surface of the eyelids and covers the front part of the eye, also known as the sclera. It helps to keep the eye moist and protected from irritants. The conjunctiva can become inflamed or infected, leading to conditions such as conjunctivitis (pink eye).

Ocular accommodation is the process by which the eye changes optical power to maintain a clear image or focus on an object as its distance varies. This is primarily achieved by the lens of the eye changing shape through the action of the ciliary muscles inside the eye. When you look at something far away, the lens becomes flatter, and when you look at something close up, the lens thickens. This ability to adjust focus allows for clear vision at different distances.

Methacrylates are a group of chemical compounds that contain the methacrylate functional group, which is a vinyl group (CH2=CH-) with a carbonyl group (C=O) at the β-position. This structure gives them unique chemical and physical properties, such as low viscosity, high reactivity, and resistance to heat and chemicals.

In medical terms, methacrylates are used in various biomedical applications, such as dental restorative materials, bone cements, and drug delivery systems. For example, methacrylate-based resins are commonly used in dentistry for fillings, crowns, and bridges due to their excellent mechanical properties and adhesion to tooth structures.

However, there have been concerns about the potential toxicity of methacrylates, particularly their ability to release monomers that can cause allergic reactions, irritation, or even mutagenic effects in some individuals. Therefore, it is essential to use these materials with caution and follow proper handling and safety protocols.

Chromium alloys are materials made by combining chromium with other metals, such as nickel, cobalt, or iron. The addition of chromium to these alloys enhances their properties, making them resistant to corrosion and high temperatures. These alloys have a wide range of applications in various industries, including automotive, aerospace, and medical devices.

Chromium alloys can be classified into two main categories: stainless steels and superalloys. Stainless steels are alloys that contain at least 10.5% chromium by weight, which forms a passive oxide layer on the surface of the material, protecting it from corrosion. Superalloys, on the other hand, are high-performance alloys designed to operate in extreme environments, such as jet engines and gas turbines. They contain significant amounts of chromium, along with other elements like nickel, cobalt, and molybdenum.

Chromium alloys have several medical applications due to their excellent properties. For instance, they are used in surgical instruments, dental implants, and orthopedic devices because of their resistance to corrosion and biocompatibility. Additionally, some chromium alloys exhibit superelasticity, a property that allows them to return to their original shape after being deformed, making them suitable for use in stents and other medical devices that require flexibility and durability.

Contact tracing is a key public health strategy used to control the spread of infectious diseases. It involves identifying and monitoring individuals (contacts) who have come into close contact with an infected person (case), to prevent further transmission of the disease. The process typically includes:

1. Case identification: Identifying and confirming cases of infection through diagnostic testing.
2. Contact identification: Finding people who may have been in close contact with the infected case during their infectious period, which is the time when they can transmit the infection to others. Close contacts are usually defined as individuals who have had face-to-face contact with a confirmed case within a certain distance (often 6 feet or closer) and/or shared confined spaces for prolonged periods (usually more than 15 minutes).
3. Contact listing: Recording the identified contacts' information, including their names, addresses, phone numbers, and potentially other demographic data.
4. Risk assessment: Evaluating the level of risk associated with each contact based on factors such as the type of exposure, duration of contact, and the infectiousness of the case.
5. Notification: Informing contacts about their potential exposure to the infection and providing them with necessary health information, education, and guidance. This may include recommendations for self-quarantine, symptom monitoring, testing, and vaccination if available.
6. Follow-up: Monitoring and supporting contacts during their quarantine or isolation period, which typically lasts 14 days from the last exposure to the case. Public health professionals will check in with contacts regularly to assess their symptoms, provide additional guidance, and ensure they are adhering to the recommended infection prevention measures.
7. Data management: Documenting and reporting contact tracing activities for public health surveillance, evaluation, and future planning purposes.

Contact tracing is a critical component of infectious disease control and has been used effectively in managing various outbreaks, including tuberculosis, HIV/AIDS, Ebola, and more recently, COVID-19.

Surface properties in the context of medical science refer to the characteristics and features of the outermost layer or surface of a biological material or structure, such as cells, tissues, organs, or medical devices. These properties can include physical attributes like roughness, smoothness, hydrophobicity or hydrophilicity, and electrical conductivity, as well as chemical properties like charge, reactivity, and composition.

In the field of biomaterials science, understanding surface properties is crucial for designing medical implants, devices, and drug delivery systems that can interact safely and effectively with biological tissues and fluids. Surface modifications, such as coatings or chemical treatments, can be used to alter surface properties and enhance biocompatibility, improve lubricity, reduce fouling, or promote specific cellular responses like adhesion, proliferation, or differentiation.

Similarly, in the field of cell biology, understanding surface properties is essential for studying cell-cell interactions, cell signaling, and cell behavior. Cells can sense and respond to changes in their environment, including variations in surface properties, which can influence cell shape, motility, and function. Therefore, characterizing and manipulating surface properties can provide valuable insights into the mechanisms of cellular processes and offer new strategies for developing therapies and treatments for various diseases.

Cataract extraction is a surgical procedure that involves removing the cloudy lens (cataract) from the eye. This procedure is typically performed to restore vision impairment caused by cataracts and improve overall quality of life. There are two primary methods for cataract extraction:

1. Phacoemulsification: This is the most common method used today. It involves making a small incision in the front part of the eye (cornea), inserting an ultrasonic probe to break up the cloudy lens into tiny pieces, and then removing those pieces with suction. After removing the cataract, an artificial intraocular lens (IOL) is inserted to replace the natural lens and help focus light onto the retina.

2. Extracapsular Cataract Extraction: In this method, a larger incision is made on the side of the cornea, allowing the surgeon to remove the cloudy lens in one piece without breaking it up. The back part of the lens capsule is left intact to support the IOL. This technique is less common and typically reserved for more advanced cataracts or when phacoemulsification cannot be performed.

Recovery from cataract extraction usually involves using eye drops to prevent infection and inflammation, as well as protecting the eye with a shield or glasses during sleep for a few weeks after surgery. Most people experience improved vision within a few days to a week following the procedure.

Eye proteins, also known as ocular proteins, are specific proteins that are found within the eye and play crucial roles in maintaining proper eye function and health. These proteins can be found in various parts of the eye, including the cornea, iris, lens, retina, and other structures. They perform a wide range of functions, such as:

1. Structural support: Proteins like collagen and elastin provide strength and flexibility to the eye's tissues, enabling them to maintain their shape and withstand mechanical stress.
2. Light absorption and transmission: Proteins like opsins and crystallins are involved in capturing and transmitting light signals within the eye, which is essential for vision.
3. Protection against damage: Some eye proteins, such as antioxidant enzymes and heat shock proteins, help protect the eye from oxidative stress, UV radiation, and other environmental factors that can cause damage.
4. Regulation of eye growth and development: Various growth factors and signaling molecules, which are protein-based, contribute to the proper growth, differentiation, and maintenance of eye tissues during embryonic development and throughout adulthood.
5. Immune defense: Proteins involved in the immune response, such as complement components and immunoglobulins, help protect the eye from infection and inflammation.
6. Maintenance of transparency: Crystallin proteins in the lens maintain its transparency, allowing light to pass through unobstructed for clear vision.
7. Neuroprotection: Certain eye proteins, like brain-derived neurotrophic factor (BDNF), support the survival and function of neurons within the retina, helping to preserve vision.

Dysfunction or damage to these eye proteins can contribute to various eye disorders and diseases, such as cataracts, age-related macular degeneration, glaucoma, diabetic retinopathy, and others.

Corneal transplantation, also known as keratoplasty, is a surgical procedure in which all or part of a damaged or diseased cornea is replaced with healthy corneal tissue from a deceased donor. The cornea is the clear, dome-shaped surface at the front of the eye that plays an important role in focusing vision. When it becomes cloudy or misshapen due to injury, infection, or inherited conditions, vision can become significantly impaired.

During the procedure, the surgeon carefully removes a circular section of the damaged cornea and replaces it with a similarly sized piece of donor tissue. The new cornea is then stitched into place using very fine sutures that are typically removed several months after surgery.

Corneal transplantation has a high success rate, with more than 90% of procedures resulting in improved vision. However, as with any surgical procedure, there are risks involved, including infection, rejection of the donor tissue, and bleeding. Regular follow-up care is essential to monitor for any signs of complications and ensure proper healing.

Amebiasis is defined as an infection caused by the protozoan parasite Entamoeba histolytica, which can affect the intestines and other organs. The infection can range from asymptomatic to symptomatic with various manifestations such as abdominal pain, diarrhea (which may be mild or severe), bloody stools, and fever. In some cases, it can lead to serious complications like liver abscess. Transmission of the parasite typically occurs through the ingestion of contaminated food or water.

Equipment design, in the medical context, refers to the process of creating and developing medical equipment and devices, such as surgical instruments, diagnostic machines, or assistive technologies. This process involves several stages, including:

1. Identifying user needs and requirements
2. Concept development and brainstorming
3. Prototyping and testing
4. Design for manufacturing and assembly
5. Safety and regulatory compliance
6. Verification and validation
7. Training and support

The goal of equipment design is to create safe, effective, and efficient medical devices that meet the needs of healthcare providers and patients while complying with relevant regulations and standards. The design process typically involves a multidisciplinary team of engineers, clinicians, designers, and researchers who work together to develop innovative solutions that improve patient care and outcomes.

Contact dermatitis is a type of inflammation of the skin that occurs when it comes into contact with a substance that the individual has developed an allergic reaction to or that causes irritation. It can be divided into two main types: allergic contact dermatitis and irritant contact dermatitis.

Allergic contact dermatitis is caused by an immune system response to a substance, known as an allergen, which the individual has become sensitized to. When the skin comes into contact with this allergen, it triggers an immune reaction that results in inflammation and characteristic symptoms such as redness, swelling, itching, and blistering. Common allergens include metals (such as nickel), rubber, medications, fragrances, and cosmetics.

Irritant contact dermatitis, on the other hand, is caused by direct damage to the skin from a substance that is inherently irritating or corrosive. This can occur after exposure to strong acids, alkalis, solvents, or even prolonged exposure to milder irritants like water or soap. Symptoms of irritant contact dermatitis include redness, pain, burning, and dryness at the site of contact.

The treatment for contact dermatitis typically involves avoiding further exposure to the allergen or irritant, as well as managing symptoms with topical corticosteroids, antihistamines, or other medications as needed. In some cases, patch testing may be performed to identify specific allergens that are causing the reaction.

Osteolysis is a medical term that refers to the loss or resorption of bone tissue. It's a process where the body's normal bone remodeling cycle is disrupted, leading to an imbalance between bone formation and bone breakdown. This results in the progressive deterioration and destruction of bone.

Osteolysis can occur due to various reasons such as chronic inflammation, mechanical stress, or certain medical conditions like rheumatoid arthritis, Paget's disease, or bone tumors. It can also be a side effect of some medications, such as those used in cancer treatment or for managing osteoporosis.

In severe cases, osteolysis can lead to weakened bones, increased risk of fractures, and deformities. Treatment typically aims to address the underlying cause and may include medication, surgery, or lifestyle changes.

Ophthalmodynamometry is a medical technique used to measure the amount of pressure or force required to flatten the cornea, which can help in the diagnosis and evaluation of various eye conditions, particularly glaucoma. It involves using a handheld device called an ophthalmodynamometer to apply gentle pressure to the eyelid while observing changes in the optic nerve head and retinal vessels through an ophthalmoscope. The test provides information about the resistance of the eyeball to external pressure, which can be useful in assessing the functioning of the eye's aqueous humor drainage system and identifying any abnormalities that may contribute to increased intraocular pressure (IOP).

The procedure typically involves several steps:

1. The patient is asked to look in different directions while the examiner observes the optic nerve head and retinal vessels through an ophthalmoscope.
2. The examiner then applies gentle pressure to the eyelid using the ophthalmodynamometer, gradually increasing the force until the cornea begins to flatten.
3. The amount of pressure required to achieve this is recorded as the ophthalmodynamometric value.
4. The examiner may repeat the process several times to ensure accurate and consistent results.
5. The results are then compared with normative data to determine whether the patient's IOP is within normal limits or if there are any signs of glaucoma or other eye conditions.

It is important to note that ophthalmodynamometry should only be performed by trained healthcare professionals, as improper technique can lead to inaccurate results and potential harm to the patient's eyes.

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As of 2017, the online store sells around 100 types of contacts, including daily and extended wear lenses, and coloured contact ... "contact lens" from AltaVista, which meant that all searches for "contact lens" were accompanied with Coastal Contacts' banner ... "Buy Contact Lenses Online & Save Money with Clearly Canada". Clearly.ca. Retrieved 2017-05-04. Jordan, David. Clearly Contacts ... Clearly, then known as Coastal Contacts, initially exclusively sold contact lenses on their storefronts. ...
For example, her research informed the design of extended wear contact lenses, which was licensed to CIBA Vision. She also ...
One of the most common causes of corneal neovascularization is iatrogenic pathology from extended contact lens wear. This is ... For contact lenses related hypoxia, ceasing the use of contact lenses is the first step until corneal neovascularization is ... and wearing contact lenses for over-extended periods of time. Superficial presentations of CNV are usually associated with ... contact lens wear, while deep presentations may be caused by chronic inflammatory and anterior segment ocular diseases. Corneal ...
An extended period of wearing contact lenses could also cause damage on the cornea surface, allowing the entry of ... could inhabit the surface of the carrying case of the contact lens. When placing the contact lens to one's eyes, invisible ... Contamination of contact lenses is another cause as fungi, bacteria and parasites, microscopic parasite acanthamoeba, in ... Efron, Nathan (2019). Contact lens complications (Fourth ed.). Philadelphia, PA. ISBN 978-0-7020-7882-8. OCLC 1076544647.{{cite ...
Alternatively, many people choose to wear contact lenses. One style is hard contact lenses, which can distort the shape of the ... Depending on the duration they are designed for, they may be worn daily or may be worn for an extended period of time, such as ... contact lenses, or surgery. Eyeglasses are the easiest and safest method of correction. Contact lenses can provide a wider ... and special types of contact lenses. In children special contact lenses appear to slow worsening of nearsightedness. A number ...
... focusing on aphakic lenses and extended-wear cosmetic contact lenses. In 1974, American Hospital Supply Corporation (AHSC), ... In 1987, JJV introduces the world's first disposable soft contact lenses under the name ACUVUE Brand Contact Lenses. AMO was ... "J&J Vision closes TearScience buyout". News: AMO contact lens solution is recalled - OCRegister.com Money: Local contact lens ... In 1959, the contact business unit started as Frontier Contact Lenses in Buffalo, New York. The surgical business unit started ...
In addition, those who wear contact lenses or have undergone eye surgeries such as LASIK are at increased risk of having dry ... A multi-state cluster of Verona Integron-mediated Metallo-β-lactamase (VIM)- and Guiana-Extended Spectrum-β-Lactamase (GES)- ... For contact lens users, specific drops should be used to avoid ingredients that can damage the contact lens. If using multiple ... Artificial tears are also used to moisten contact lenses and in eye examinations. Although artificial tears are used to mimic ...
"Treatment of persistent epithelial defect with extended wear of a fluid-ventilated gas permeable scleral contact lens." ... Contact Lens, 2005; 31 (3) (130-134). Moore, Abigail Sullivan (July 2003). "A New Lens Restores Vision and Brings Relief". The ... "New Contact Lens Lets Blind See". CBS News. 4 September 2003. "Chronic Eye Pain Following Laser Keratorefractive Surgery - By ... In 1986, he developed a practical, gas-permeable scleral contact lens to treat and restore vision of eyes with many corneal ...
The U.S. Food and Drug Administration approved the sale of the first extended wear contact lenses, which could be left in the ... "Long-Wear Contact Lenses Approved by U.S. Agency", New York Times, January 15, 1981 Museum of Broadcast Communications, ... The Hydrocurve II lenses were manufactured by a subsidiary of Revlon. Hill Street Blues, described as "one of the most ... who briefly brought back the popularity of women's wear with padded shoulders. Dynasty was the #1 rated TV program in the ...
... a simple example being the development of extended-wear contact lenses. Due to these successes, the huge potential of ... An example of a proposed structure for plasma polymerized ethylene demonstrating a large extend of cross-linking and branching ... The use of plasma polymers to coat plastic lenses is increasing in popularity. Plasma depositions can easily coat curved ...
... contact lenses MeSH E07.532.276.360 - contact lenses, hydrophilic MeSH E07.532.276.360.220 - contact lenses, extended-wear MeSH ... lenses, intraocular MeSH E07.695.510 - maxillofacial prosthesis MeSH E07.695.510.500 - mandibular prosthesis MeSH E07.695.540 ... E07.532.300 - eyeglasses MeSH E07.532.460 - lenses, intraocular MeSH E07.565.500 - quantum dots MeSH E07.605.500 - metered dose ...
The three AC series lenses, extended from the FD lens mount, described below, are an exception). While Canon could have adapted ... The lenses communicated with the T80 via a modified FD mount with added electrical contacts. They lacked an aperture ring, and ... This prevents any mechanical wear, which could conceivably reduce the very precise lens-to-film distance or introduce ... All of these lenses received S.S.C. coating, with the sole exception of the 50mm f/1.8 lens. The original breech-lock FD lenses ...
... by a bacterium known as Pseudomonas aeruginosa which forms in the eye's biofilm as a result of extended soft contact lens wear ... "Microbial contamination of contact lenses, lens care solutions, and their accessories: a literature review". Eye & Contact Lens ... contact lenses that have been left in too long. Damage may result when the lenses are removed, rather than when the lens is ... Ensuring both a proper contact lens fit and the compliance of the person with care measures can prevent contact lens-related ...
Contact lenses that display AR imaging are in development. These bionic contact lenses might contain the elements for display ... which are worn on the human body. A head-mounted display (HMD) is a display device worn on the forehead, such as a harness or ... One innovation, the Extended Virtual Table, separates the virtual from the real by including beam-splitter mirrors attached to ... "Contact Lenses Can Display Your Text Messages". Mashable.com. Retrieved 13 December 2012. O'Neil, Lauren. "LCD contact lenses ...
The lens was originally indicated for seven-day extended wear and later became a daily wear lens. Today, there is a line which ... Surevue contact lenses were a less expensive alternative to Acuvue. Acuvue - (etafilcon A) Original 1-2 week lenses, introduced ... Acuvue lenses got their start at Frontier Contact Lens Company, founded in Buffalo, New York in 1959 by Dr. Allen Isen, George ... Daily Disposable Contact Lenses: 1-Day Acuvue Moist - (etafilcon A) hydrogel material (available for astigmatism and presbyopia ...
Johnson contact lenses, Stride gum, KFC, and Chevrolet. After Chan's release from prison, he lived with his mother in Taipei, ... He extended a deep bow both before and after his speech. Before his arrest in August 2014, Chan was filming Monk Comes Down the ... keeping a low profile, and often wearing a mask to avoid being seen in public. In 2020, despite his criminal record and having ...
Applications of contact mechanics further extend into the micro- and nanotechnological realm. The original work in contact ... wear, etc.). They considered the contact between a smooth rigid plane and a nominally flat deformable rough surface covered ... Hertz was attempting to understand how the optical properties of multiple, stacked lenses might change with the force holding ... The model proposed by Greenwood and Tripp (GT), extended the GW model to contact between two rough surfaces. The GT model is ...
Actor Edward James Olmos has brown eyes, but when playing William Adama he wore contact lenses that make Adama's eyes blue. ... Extended Cut)". Battlestar Galactica (2004 TV series). "A Day in the Life". Battlestar Galactica (2004 TV series). "You can't ... When the Cylons locate New Caprica after a year of no contact with the human race, Adama is forced reluctantly to flee with all ... Retaking command of his ship, Adama contacts Roslin on the basestar who has been demanding the mutineers surrender and ...
The character's original design included contact lenses to give Hemmer white eyes, but Horak found them painful to wear and an ... Legacy designed a "fairly simple forehead piece" that is a 'V' shape, extending around the eyes and over the nose. Special ... They also created green hoop earrings for Gooding to wear in the episode based one ones worn by Nichols in The Original Series ... Croft and her team had access to one of the costumes worn by Shatner in Star Trek II: The Wrath of Khan (1982) for reference. ...
A group of men, wearing white contact lenses, rise from the dead and form a crowd around her. The driver returns and approaches ... A week after, an extended play was released for digital download and streaming. The tracklist includes the Disclosure version ...
He wears contact lenses. He married Melissa, and had a son, Bobby Joseph Pope, in May 2016. He also has a daughter, Millie. ... Indeed, his loan spell was extended into a second month. His third goal for the club came on 22 March, and was enough to rescue ... "Pope extends loan stint at Barrow". BBC Sport. 11 September 2006. Retrieved 27 January 2011. Baggaley, Michael (23 June 2020 ... Following this his loan deal was extended into a third month. However the loan spell was terminated three weeks early following ...
... although they are permitted to wear glasses or contact lenses. They must also have good communication skills, good reflexes and ... At this time, the major leagues only extended as far west as St. Louis, Missouri, and as far south as Washington, D.C. This ... though many relationships have been renewed and endure for extended time periods. For example, the Omaha Storm Chasers ( ...
The radiating contact lens used on the eyes were previously made by XFX for the film Innocent Blood (1992); while a light- ... The split-second shot of Flagg's fingers flexing backwards was done with the hand palm up, but the actor wore an appliance for ... For Flagg's hands, the effects team went for a recurring theme of eccentricities in how they worked, such as the extending of a ... a man on a cross wearing a crown of drug needles with the sign "Drug Addict" on his neck, and open-eyed corpses. A lot of these ...
Hom, M.M.; Bruce, A.S. (2006). Manual of Contact Lens Prescribing and Fitting. Butterworth-Heinemann. p. 310. ISBN 978-0-7506- ... Disposable tableware Durability Durable good Extended producer responsibility Litter Paper napkin Paper recycling Planned ... withdrawn from circulation when worn Ballpoint pens, erasers, and other writing implements Movie sets and theater sets Gift ... and other oral care products Hospital aprons Disposable panties in postpartum Contact lenses Non-rechargeable batteries are ...
... and contact lens wear. The dominant eye has more neural connections to the brain than the other eye does. According to a sixty- ... The observer extends both arms, brings both hands together to create a small opening, then with both eyes open views a distant ... The observer extends one arm, then with both eyes open aligns the thumb or index finger with a distant object. The observer ... Lens fogging technique. The subject fixates a distant object with both eyes open and appropriate correction in place. A +2.00 ...
He also was incorporated with a pair of hypnotic contact lenses which Dick used to mind control someone if they looked directly ... He wears a black leather strap and buckles on each of his forearms. This redesign intends to harken back to the iconic black- ... His former costume was a stylized red "wing" across his shoulders and extending to his hands, coloring his two middle fingers ... William Cobb forces Ric to wear goggles and puts Dick under his spell. As a Talon, Grayson fights off other Nightwing heroes. A ...
During filming, Donner noticed that when Kidder wasn't wearing her contact lenses, "she kept her eyes really wide" and moved ... The extended version of the scene shows the girl to be a young Lois telling her parents (portrayed by Kirk Alyn and Noel Neill ... He said it "gave her this wonderful character" and instructed her to not wear them on camera for the duration of the shoot. One ... DC Extended Universe) Lois Lane in other media Petrou, David Michael (1978). The Making of Superman the Movie. Warner Books. pp ...
What are Extended Wear Contact Lenses?. Extended wear silcone hydrogel contact lenses. Extended wear silcone hydrogel contact ... How long can I continue wearing extended wear contact lenses?. Silicone hydrogel extended wear contact lenses are approved for ... Risks with Extended Wear Contact Lenses. In past, EW contact lenses would run the risks of infections. Microorganisms grow in ... Categorized as Color Contact Lens Basic Info Tagged extended wear contact lenses, orthokeratology, Silicone hydrogel, Silicone ...
Shop extended and continuous wear contact lenses online up to 50% cheaper than the high street. Enjoy Price Match Guaranteed & ... How long can you wear extended wear contact lenses?. Extended wear contact lenses can be safely worn for up to 6 nights as per ... Extended Wear Contact Lenses Feel Good Contacts is one of the most trusted suppliers of extended wear contact lenses. Rated ... Extended wear toric contact lenses. At Feel Good Contacts, you can browse through a variety of extended wear toric contact ...
... their number increases over time with extended contact lens wear. Microcysts tend to appear three months after contact lens ... the reduction was more pronounced in patients wearing hard contact lenses than in patients wearing soft contact lenses. ... Many contact lens-induced changes in corneal structure are reversible if contact lenses are removed for an extended period of ... steepening was found in patients wearing soft contact lenses than in patients wearing rigid gas permeable contact lenses, ...
Contact prescription vs. eyeglass prescription: They're not the same. Learn the differences - and why you need both. ... is especially important if you want extended-wear contact lenses or you occasionally fall asleep while wearing your contacts. ... HomeContact lensesContact Types Are contact lens and spectacle prescriptions the same? By Aimee Rodrigues; reviewed by Gary ... Can anyone get a contact lens prescription?. No, not everyone who needs eyeglasses can wear contact lenses successfully. ...
Buy Coopervision contact lenses direct online. We have a selection of options and quantities available. Free UK delivery on ... CooperVision manufacturer contact lenses that can be worn for 12 plus hours per day and extended wear contact lenses that can ... Do CooperVision Make Their Own Contact Lens Solutions. That will depend on which CooperVision contact lens you are wearing. ... Show Most Popular Contact Lenses Browse ALL Contact Lenses Shop by Colour Blue Green Brown Grey Hazel Violet. Optician Brands ...
This is also suitable for those with sensitive eyes and people who wear contact lenses. This mascara is long-lasting, smudge- ... My good friend Amanda Batula uses the LOreal Double Extend Mascara religiously, and she has the best lashes. So I copied her, ... I can wear my hair up, down, in a high top knot-however I want, and I am not limited like I have been in the past. ... About UsSubscribeContact UsFAQCareersClosed CaptioningWatch Full EpisodesSitemapE! International TV ChannelsCustomer Support ...
... and contact lens wear (eg, daily disposable soft lenses, extended-wear soft lenses, gas-permeable lenses, hard ... Contact lens trauma. Contact lens-induced epithelial defects or direct trauma during lens insertion or removal can cause ... After the contact lens is removed, the patient may feel discomfort; however, no pain occurs when the lens is worn because it ... Corneal abrasions due to soft lenses are observed most frequently with tight or extended-wear lenses. In these situations, ...
Z-1228-2020 - Coopervision Vertex Toric /2 Clear Toric- Power +2.25 -0.75/120 Soft (hydrophilic) Contact Lens (extended wear) 2 ... Z-1227-2020 - Coopervision Vertex Toric /2 Clear Toric- Power -2.50 -0.75 /90 Soft (hydrophilic) Contact Lens (extended wear) 2 ...
Ocular Surface Inflammation Between Daily Wear and Extended Wear Soft Contact Lenses. Anterior Segment Disease & Miscellaneous ... The Key To An Iris Coloboma: Prosthetic Soft Contact Lens. Soft Specialty & Hybrid lens applications/prosthetic lenses. ... Management of Achromatopsia with Tinted Contact Lenses. Soft Specialty & Hybrid lens applications/prosthetic lenses. Clinical ... Utilizing Dual Sagittal Depth Lens Design to Ensure On-Eye Stability of Front Toric Scleral Contact Lenses. Scleral lenses ...
... simplex keratitis and lens wear. Other investigations reported risk factors that include extended wear and lens wear during ... In addition, patients should replace lenses as prescribed and avoid wearing contact lenses during water activities. ... contact lens care. Mycotic Keratitis and Lens Care. BY MICHAEL A. WARD, MMSC, FAAO ... Mycotic (fungal) keratitis (Figure 1) is an uncommon complication of contact lens wear. At least 35 genera of fungi have been ...
Order online or call 1-800 LENSFAST Free Shipping As Low As $86.95 Extended Wear: Monthly Replacement, Multi-Packaged Spherical ... Buy Discount Contact Lenses Acuvue, CibaVision, CooperVision, Bausch & Lomb. ... PureVision® contact lenses: Experience Life in High Definition! Bausch & Lomb introduces PureVision contact lenses the ... Worlds Best Contact Lens Store Ⓡ $5.49 Shipping, No Hidden Processing Fees - Free For All U.S. Orders Over $149.95. ...
Tried contacts in the past but stopped due to discomfort or poor quality? It may be time to try again. Our doctors will help ... Extended Wear Contact Lenses. Extended wear contact lenses are gas-permeable or soft lenses designed for up to 30 days of ... Soft Contact Lenses. Soft contacts are the most common type of contact lenses and account for over 85% of contact lenses ... Some doctors will not recommend extended wear lenses for these reasons.. Tinted or Cosmetic Contact Lenses. Tinted contact ...
Tried contacts in the past but stopped due to discomfort or poor quality? It may be time to try again. Our doctors will help ... Extended Wear Contact Lenses. Extended wear contact lenses are gas-permeable or soft lenses designed for up to 30 days of ... Soft Contact Lenses. Soft contacts are the most common type of contact lenses and account for over 85% of contact lenses ... Some doctors will not recommend extended wear lenses for these reasons.. Tinted or Cosmetic Contact Lenses. Tinted contact ...
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Over-use of contact lenses (often extended-wear lenses) can lead to conjunctivitis. ... A similar condition can occur in long-time contact lens wearers. It may make it difficult to continue to wear contact lenses. ... behind the lens) and the aqueous humor (in front of the lens). The lens itself is flexible and suspended by ligaments which ... behind the lens) and the aqueous humor (in front of the lens). The lens itself is flexible and suspended by ligaments which ...
But for those still wrestling with fiddly contact lenses, these pastimes can be fraught with concerns. ... The answer is simple: Contact lenses and swimming really do not mix. In fact, the consequences of wearing contact lenses while ... especially during extended use. This can affect the health of the epithelium (which forms the layer over the cornea). Daily use ... The risks of mixing contact lenses and swimming. Wearing contact lenses during any water-based activities puts you at an ...
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These lenses are made from high-quality materials that ensure extended comfort during daily wear. They can be used to enhance ... Colored contacts (1) All collections * *Shop by Color Toggle submenu Shop by Color * Red Contacts ... Cosplay contacts (2) All collections * *Shop by Color Toggle submenu Shop by Color * White Contacts ... The Geo Ultra Black contact lenses are designed to make the eyes appear larger and more defined,creating a dolly and cute big ...
... contact lenses and other products at great prices. ... will help extend the life of your contact lenses and keep your ... Hygiene is critical to wearing your contact lenses. Contact lenses can significantly improve your vision but its very ... Replace your contact lens case at least once every three months. *Dont "top off" solution. Use only fresh contact lens ... Rub and rinse your contact lens case with sterile contact lens solution. Never use water. ...
Im interested in wearing contact lenses Im already wearing contact lenses Im new to contact lenses ... movement extends to eye health as well, especially for... ... Wearing Contact Lenses for the First Time The first time you ... 5 Tips for Traveling with Contact Lenses The travel season is upon us again! Are you and your contact lenses ready? Whether ... Teenagers and Contact Lenses Teenagers who are self-conscious about how they look (i.e. all of them) often want to replace ...
NA (No/unknown if contact lenses worn) 1117 Soft lenses, extended wear 609 1. Mentioned 2,487 2. Not mentioned 33 9. Unknown ... NA (No/unknown if contact lenses worn) 1116 Soft lenses, daily wear 1,670 1. Mentioned 1,426 2. Not mentioned 33 9. Unknown ... NA (No/unknown if contact lenses worn) 1118 Intraocular lenses 17 1. Mentioned 3,079 2. Not mentioned 33 9. Unknown 41,104 ... contact lenses worn) 1119 Other 166 1. Mentioned 2,930 2. Not mentioned 33 9. Unknown 41,104 Blank. NA (No/unknown if contact ...
Placing circuitry on contact lenses could have numerous uses and it's already being done in the lab. Commercially viable ... Most of us consider contact lenses as merely a way to correct vision without wearing glasses. University of Washington ... As far as were concerned, the possibilities extend as far as the eye can see, and beyond. ... Circuits on contact lenses eye inviting possibilities Placing circuitry on contact lenses could have numerous uses and it' ...
Treatment of persistent corneal epithelial defect with extended wear of a fluid-ventilated gas-permeable scleral contact lens. ... Use eye protective devices (eg, goggles, moisture chambers, scleral lenses) when topical medications are not sufficient. ...
Discover the ultimate lenses for correcting astigmatism with optimised Biofinity Toric monthly contact lenses (3-pack) by ... Monthly Contact Lenses. Toric Contact Lenses. Extended Wear Contact Lenses. Silicone Hydrogel Contact Lenses. Contact lenses ... However, they can also be worn as extended wear contact lenses for up to six nights and seven days after approval from an ... Flexible wear - These monthly contact lenses feature the possibility of continuous wear for up to six nights and seven days ...
Contact lens intolerance is a common condition that affects many individuals who wear contact lenses. Know how you can enjoy ... To prevent contact lens intolerance, it is essential to follow proper lens care instructions, avoid wearing lenses for extended ... However, wearing contact lenses can lead to a condition known as contact lens intolerance (CLI). CLI is a broad term describing ... Q: Can I continue wearing contact lenses if I have contact lens intolerance?. It is advisable to consult with an eye care ...
Extended wear contacts have also been approved by the FDA for longer wear times compared to other disposable contacts. Sleeping ... of contact lens wearers now use soft contact lenses.. Different Types of Contact Lenses. While most individuals prefer to wear ... Bandage lenses. Proper Use of Contact Lenses. Since different contact lenses have different durations in wear and schedules for ... Rigid or hard contact lenses were made from plastic and were first produced in the U.S. between 1938-1940. Soft contact lenses ...
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ColourVUE Crazy Lens Lenses Material : Hydrogel Terpolymer Extended or overnight wear: No ... Contact lenses Types of lenses. Daily lenses Bi-weekly lenses Monthly lenses Toric lenses Multifocal lenses Coloured lenses ... CONTACT LENSES. Starting with Lenses Inserting and Removing Contact Lenses Lens Care Basics - solutions & cases How do I read ... White WhiteOut contact lenses - ColourVue Crazy (2 coloured lenses) CRAZY LENS - Barbie Pink - plano (2 daily coloured lenses) ...
  • On average, over five times as many epithelial microcysts than normal have been observed in long-term contact lens wearers. (wikipedia.org)
  • Increased endothelial polymegethism is also found in long-term wearers of rigid gas permeable lenses as soon as one week after contact lens wear begins. (wikipedia.org)
  • This change is indicated by significant increases in Max/Min cell size ratio in contact lens wearers. (wikipedia.org)
  • these problems are sometimes correlated with astigmatism in contact lens wearers and are thought to be caused by hypoxia, surface molding, and chronic and mild trauma to the cornea from contact lens use. (wikipedia.org)
  • Air Optix Night & Day Aqua is one of the most popular 30-day continuous wear contact lens among lens wearers. (feelgoodcontacts.com)
  • CooperVision offer a wide range of contact lenses from their groundbreaking MiSight, contact lenses proven to slow the progression of myopia in children (1) to their recently launched Digital Zone Optics Lens, which is specifically designed to deal with the increasing need of contact lens wearers who lead active digital lifestyles, not forgetting the first full range of Daily disposable silicone hydrogel contact lenses, Clariti 1 Day. (contactlenses.co.uk)
  • A s I write this column, the U.S. Food and Drug Administration and Centers for Disease Control and Prevention are actively investigating cases of Fusarium keratitis among contact lens wearers who reported using Bausch & Lomb's ReNu with MoistureLoc MPS formulation. (clspectrum.com)
  • Contact lens wearers are especially susceptible. (londonvisionclinic.com)
  • Wearing tight-fitting goggles can help to prevent water from getting to your eyes, but contact lens wearers are still at a higher risk of acquiring an infection . (londonvisionclinic.com)
  • A similar condition can occur in long-time contact lens wearers. (adam.com)
  • Some eye products or eye drops aren't safe for contact wearers. (communityeye.com)
  • The Centers for Disease Control and Prevention estimates that 45 million people in the United States wear contact lenses and two-thirds of contact lens wearers are female. (usqeyecare.com)
  • Soft contact lenses were first introduced in the U.S. in 1971 and it is estimated that 90% of contact lens wearers now use soft contact lenses. (usqeyecare.com)
  • What's the difference between a contact lens and glasses prescription? (allaboutvision.com)
  • But, depending on the degree of your refractive error and the type of contacts prescribed, the powers specified on your contact lens prescription may be significantly different from those on your glasses prescription. (allaboutvision.com)
  • Also, a contact lens prescription contains additional specifications that are not included on a glasses prescription, and these can be determined only after a comprehensive contact lens exam and fitting. (allaboutvision.com)
  • For some prescriptions, they do not offer the same visual acuity as gas permeable lenses or glasses. (polkcityeyecare.com)
  • Bifocal contact lenses, like bifocal glasses, have more than one power. (polkcityeyecare.com)
  • Like bifocal glasses, these lenses allow an individual to enjoy clear vision at all distances. (larsonvisioncare.com)
  • But for those still wrestling with glasses and fiddly contact lenses , these summertime activities can be fraught with concerns. (londonvisionclinic.com)
  • What's the problem with glasses and contacts? (londonvisionclinic.com)
  • You might think that wearing glasses and contact lenses by the pool or at the beach is no big deal - but let's take a look at the bigger picture. (londonvisionclinic.com)
  • You could correct your refractive error for good and wave "goodbye" to your contact lenses and glasses. (londonvisionclinic.com)
  • People who exercise regularly enjoy a myriad of benefits to their body, including healthier eyes , but wearing glasses while working out can be a challenge. (coopervision.com)
  • Most of us consider contact lenses as merely a way to correct vision without wearing glasses. (zdnet.com)
  • You might find contact lenses more convenient than glasses for temporary vision correction. (360eyecare.ca)
  • Give your eyes a break by taking one day off per week from wearing contact lenses and using your glasses instead. (360eyecare.ca)
  • If your contact lenses are causing irritation, wearing your backup glasses can provide relief until your eyes settle down. (360eyecare.ca)
  • The physicians at Union Square Eye Care are skilled at assessing your vision and determining the most appropriate contact lenses for your use if recommended as an option to glasses. (usqeyecare.com)
  • Because the cornea becomes cone-shaped, patients cannot wear contact lenses for extended periods, and glasses can lose their effectiveness. (medscape.com)
  • In this study, all participants had 20/400 vision with glasses before transplantation and could not wear contacts for extended periods of time. (medscape.com)
  • There is some evidence to show that rigid gas permeable contact lenses are capable of slowing myopic progression after long-term wear. (wikipedia.org)
  • Greater corneal steepening was found in patients wearing soft contact lenses than in patients wearing rigid gas permeable contact lenses, suggesting that the latter may slow the progression of myopia by flattening the cornea. (wikipedia.org)
  • Long-term use of rigid gas permeable contact lenses has been associated with slower myopic progression. (wikipedia.org)
  • In most cases, the diameter of soft contact lenses ranges from 13.5 to 14.5 millimeters, and the diameter of rigid gas permeable (GP) contacts ranges from 8.5 to 9.5 millimeters. (allaboutvision.com)
  • Examples include corneal or epithelial disease (eg, dry eye ), superficial corneal injury or ocular injuries (eg, those due to foreign bodies ), exposure to ultraviolet light, and contact lens wear (eg, daily disposable soft lenses, extended-wear soft lenses, gas-permeable lenses, hard polymethylmethacrylate lenses). (medscape.com)
  • Extended wear contact lenses are gas-permeable or soft lenses designed for up to 30 days of continuous safe wear. (polkcityeyecare.com)
  • Rigid Gas Permeable (RGP), or just Gas Permeable (GP) lenses are sometimes mistaken for old-fashioned lenses. (polkcityeyecare.com)
  • Gas permeable lenses also allow more oxygen to the cornea than traditional soft contact lenses. (polkcityeyecare.com)
  • These lenses are available in both soft and gas-permeable designs. (polkcityeyecare.com)
  • The patient had already developed significant corneal scarring and visual debilitation by the time topical steroids were initiated, and his final corrected visual acuity with rigid gas permeable contact lenses was 20/50 and 20/80 in the right and left eye, respectively. (bvsalud.org)
  • Many patients with keratoconus can be treated with cross-linking and gas-permeable or advanced scleral contact lenses, he explained. (medscape.com)
  • At Feel Good Contacts, you can browse through a variety of extended wear toric contact lenses for people with astigmatism , such as Acuvue Oasys for Astigmatism , Bausch & Lomb Ultra for Astigmatism , and Biofinity Toric . (feelgoodcontacts.com)
  • Biofinity XR Toric contact lenses are specially designed for those with astigmatism. (feelgoodcontacts.com)
  • Like a spectacle prescription, a contact lens prescription includes the lens power required to correct your refractive error - whether it's myopia (nearsightedness), hyperopia (farsightedness) and/or astigmatism . (allaboutvision.com)
  • Toric contact lenses help correct astigmatism. (polkcityeyecare.com)
  • Toric contact lenses are an excellent choice for those with astigmatism. (larsonvisioncare.com)
  • Get specially designed toric color contacts to correct astigmatism and eye color. (pinkyparadise.com)
  • At Pinky Paradise, we offer a wide range of high-quality Colored Contacts for Astigmatism . (pinkyparadise.com)
  • Contacts that are made up of silicone hydrogel material are usually safe to be called extended wear contact lenses. (uniqso.com)
  • Silicone hydrogel contact lenses are used in Orthokeratology treatment, where these lenses are left in eyes while you sleep to reshape the cornea. (uniqso.com)
  • Silicone hydrogel contact lenses on the other hand, allow 5times more supply of oxygen that prevent discomfort caused by hypoxia. (uniqso.com)
  • Silicone hydrogel extended wear contact lenses are approved for 7 days of continuous wear. (uniqso.com)
  • For sensitive eyes, a doctor usually suggests silicone hydrogel soft contact lenses with a short replacement period from 7 days to 30 days at maximum with intervals. (uniqso.com)
  • These silicone hydrogel lenses are highly breathable and offer incredible comfort all day long due to the unique Aquaform Technology. (feelgoodcontacts.com)
  • Oxygen flows freely through these silicone hydrogel contact lenses ensuring breathability. (feelgoodcontacts.com)
  • Biofinity - A silicone hydrogel continuous wear contact lens, containing CooperVisions patented Aquaform technology, to create a hydrophilic silicone hydrogel lens that allows greater levels of oxygen to flow freely through the lens to the eye helping them stay moist and comfortable all day long and even overnight. (contactlenses.co.uk)
  • Clarity 1 Day - A daily disposable contact lens made from a soft and flexible silicone hydrogel, Clariti 1 day are exceptionally breathable contact lenses that let a large amount of oxygen pass through them to the eyes. (contactlenses.co.uk)
  • Bausch & Lomb introduces PureVision contact lenses the revolutionary family of silicone hydrogel contact lenses that combine breathtaking clarity with incredible health and comfort. (contactlens.com)
  • At Feel Good Contacts, you can browse through a variety of extended wear multifocal contact lenses for people with presbyopia, such as Bausch & Lomb Ultra for Presbyopia , Air Optix Plus HydraGlyde Multifocal and Biofinity Multifocal . (feelgoodcontacts.com)
  • Acuvue Oasys Multifocal contact lenses feature a Pupil Optimised Design for exceptional visual performance across all distances. (feelgoodcontacts.com)
  • Rigid and soft bifocal and multifocal contact lenses can also be successful, but the fitting procedure is time-consuming because precise alignment is essential. (msdmanuals.com)
  • Knowledge concerning the form and function of the cornea and the various types of contact lenses and their common complications is important to understanding this article. (wikipedia.org)
  • There are other types of contact lenses for specific vision conditions. (usqeyecare.com)
  • The effects of extended contact lens wear on the cornea have been studied extensively and are well-documented. (wikipedia.org)
  • When determining the effects of long-term contact lens use on the cornea, many studies do not differentiate between users of hard and soft contact lenses, while studies that have made this differentiation have found similar results. (wikipedia.org)
  • This is probably because most contact lens-induced changes to the cornea are caused by hypoxia, which occurs as long as any physical barrier to the surface of the cornea is present. (wikipedia.org)
  • Long-term use of soft hydrogel contact lenses has been shown to alter the following in the cornea: epithelial oxygen uptake, epithelial thickness, stromal thickness, and corneal endothelial morphology. (wikipedia.org)
  • They allow oxygen to permeate through the lens material to the cornea. (polkcityeyecare.com)
  • RGP lenses are more pliable, more comfortable, and they allow oxygen to the cornea. (polkcityeyecare.com)
  • Poor contact lens hygiene may lead to infection of the cornea or persistent inflammation. (msdmanuals.com)
  • There is too little moisture to keep the lens floating above the cornea. (msdmanuals.com)
  • A small foreign particle (eg, soot, dust) becomes trapped between the lens and the cornea. (msdmanuals.com)
  • which is a potentially vision-threatening infection of the cornea, is suspected when a contact lens wearer has intense eye pain (both foreign body sensation and ache), decreased vision, redness, photophobia, and tearing. (msdmanuals.com)
  • Donor tissue is inserted into the middle layer of the recipient eye through a tiny tube, which strengthens and flattens the cornea, making it easier to wear contact lenses. (medscape.com)
  • CooperVision sell their products in over 130 countries around the world, so you should have no problem in replenishing your contact lens supply, almost every high street optical practice should fit and supply a wide range of CooperVision products. (contactlenses.co.uk)
  • You can also find CooperVision contact lenses at reputable online suppliers , where you can often find them at lower prices than on the high street. (contactlenses.co.uk)
  • Their breathable design ensures that your eyes stay fresh and healthy, even during extended wear. (freshtone.shop)
  • Made with high-quality materials that are safe, comfortable, and breathable, making them perfect for extended wear. (freshtone.shop)
  • Crafted with the highest quality materials and the latest technology, our lenses are safe, comfortable, and breathable, making them perfect for daily wear or special occasions. (freshtone.shop)
  • In certain instances, hard contact lenses were shown to cause the same changes in corneal structure as soft contact lenses, though these changes were more dramatic because rigid lenses are capable of inflicting greater trauma on the eyes. (wikipedia.org)
  • Furthermore, the reduction was more pronounced in patients wearing hard contact lenses than in patients wearing soft contact lenses. (wikipedia.org)
  • For this reason, hard contact lenses are obsolete. (polkcityeyecare.com)
  • The old hard contact lenses that people know are rarely used today. (polkcityeyecare.com)
  • Rigid or hard contact lenses were made from plastic and were first produced in the U.S. between 1938-1940. (usqeyecare.com)
  • Avoid wearing contact lenses while showering to prevent serious eye infections caused by parasites like acanthamoeba keratitis found in water. (feelgoodcontacts.com)
  • Mycotic (fungal) keratitis (Figure 1) is an uncommon complication of contact lens wear. (clspectrum.com)
  • Rosa et al (1994) reported that Fusarium sp accounted for 62 percent of 151 cases of fungal keratitis in south Florida over a 10-year period (1982 to 1992) and revealed that the most common risk factor is trauma, including contact lens wear. (clspectrum.com)
  • The reported risk factors in New York were different from previous reports, identified as HIV positivity (24.6 percent) and chronic surface disease (22.6 percent), followed by trauma, H. simplex keratitis and lens wear. (clspectrum.com)
  • This is why eye doctors try to avoid prescribing overnight EW contact lenses. (uniqso.com)
  • However, we recommend you consult your optician before wearing your lenses overnight. (feelgoodcontacts.com)
  • Clean the lenses overnight and reuse them for another 6 nights, repeating the process for up to 30 days. (feelgoodcontacts.com)
  • Rinse your lenses thoroughly with a recommended solution before soaking the contacts overnight in a multi-purpose solution that completely covers each lens. (communityeye.com)
  • The risk increases about 15 times if contact lenses are worn overnight. (msdmanuals.com)
  • Picture waking up and beginning your day without the irritation and challenges that come with wearing contacts. (360eyecare.ca)
  • When phosgene gas contacts moist or wet skin, it may cause irritation and erythema. (cdc.gov)
  • Direct contact with liquid phosgene under pressure can cause frostbite as well as severe irritation and corrosive effects. (cdc.gov)
  • In addition, patients should replace lenses as prescribed and avoid wearing contact lenses during water activities. (clspectrum.com)
  • It is important to replace disposable contacts as suggested to avoid eye infection. (polkcityeyecare.com)
  • However, it is vital to replace these lenses to avoid eye infections. (larsonvisioncare.com)
  • Contact lenses can significantly improve your vision but it's very important to care for them properly to avoid potentially serious infections or other problems. (communityeye.com)
  • Avoid wearing contacts while swimming or in a sauna, as water can introduce harmful microorganisms to your eyes. (360eyecare.ca)
  • Since different contact lenses have different durations in wear and schedules for replacement, proper guidance is essential to avoid injury and damage to the eyes. (usqeyecare.com)
  • 184 controls matched geographically and by contact lens tially blinding, corneal infection, was detected in the United use. (cdc.gov)
  • If you want to wear both contact lenses and eyeglasses, you will need two separate prescriptions. (allaboutvision.com)
  • No, not everyone who needs eyeglasses can wear contact lenses successfully. (allaboutvision.com)
  • Teenagers who are self-conscious about how they look (i.e. all of them) often want to replace their eyeglasses for contact lenses. (coopervision.com)
  • Neither rigid nor soft contact lenses offer the eyes the protection against blunt or sharp injury that eyeglasses do. (msdmanuals.com)
  • If you have tried contacts in the past, but stopped due to discomfort or poor quality, it may be time to try again. (polkcityeyecare.com)
  • Sleeping with contact lenses, however, is never recommended since it can pose a risk for infection and other complications. (usqeyecare.com)
  • None of the 19 patients studied experienced any complications after surgery, and all could wear contact lenses for extended periods. (medscape.com)
  • What's more, most lens-associated corneal ulcers are preventable with proper practitioner instruction coupled with patient compliance with the instructions. (clspectrum.com)
  • This measurement (abbreviated BC) is the curvature of the back surface of the contact lens. (allaboutvision.com)
  • The base curve describes the curvature of the contact lens surface, i.e. how well the lens fits the shape of your eye. (lentiamo.co.uk)
  • These lenses are convenient and low-maintenance compared to traditional soft lenses. (polkcityeyecare.com)
  • However, if a surgical solution is needed, those with very steep but clear corneas unsuitable for a scleral lens might be candidates for the procedure. (medscape.com)
  • Not all contact lenses can be left in eyes for a night since soft contact lenses obstruct oxygen permeation to some degree. (uniqso.com)
  • Among patients who have worn soft hydrogel contact lenses for over a year, significant reductions in epithelial oxygen uptake, epithelial thickness, and stromal thickness have been recorded, while an increase in endothelial polymegethism was found. (wikipedia.org)
  • Either soft or rigid lenses are used to correct myopia and hyperopia. (msdmanuals.com)
  • Lens care instructions should include hand washing, daily use of fresh solutions (do not top-off), daily rinsing and air drying of storage cases, regularly replacing storage cases and scalding the case weekly with freshly boiled water. (clspectrum.com)
  • They need to be worn regularly (although not every day) to achieve optimal comfort. (polkcityeyecare.com)
  • See us for your regularly scheduled contact lens and eye examination. (communityeye.com)
  • For yearly replacement contact lenses, we also recommend regularly changing the lens case , at least with every new bottle of solution. (alensa.com.mt)
  • Soft disposable contacts are available in daily, biweekly, and monthly varieties. (usqeyecare.com)
  • Extended wear contacts have also been approved by the FDA for longer wear times compared to other disposable contacts. (usqeyecare.com)
  • Non-disposable contacts can be reused for multiple months if cared for properly. (usqeyecare.com)
  • Also known as, continuous wear contact lenses, these can be a good option for individuals with busy and hectic schedules or for those who occasionally find themselves falling asleep while wearing their lenses. (feelgoodcontacts.com)
  • This is especially important if you want extended-wear contact lenses or you occasionally fall asleep while wearing your contacts. (allaboutvision.com)
  • Some individuals experience CLI symptoms occasionally, while others suffer from them daily, leading to an inability to wear contacts altogether. (360eyecare.ca)
  • Contact lenses occasionally cause painless superficial corneal changes. (msdmanuals.com)
  • Perfect your cosplay with our daily lenses! (uniqso.com)
  • From natural-looking to bold and dramatic contact lenses or theatrical cosplay contacts & halloween contacts , each piece is a treasure to transform your looks. (pinkyparadise.com)
  • Extended wear contact lenses for sleeping: Are they right for you? (allaboutvision.com)
  • Sleeping with extended wear contacts increases your risk of infection, corneal ulcers, and abnormal blood vessel growth. (larsonvisioncare.com)
  • Sleeping in your lenses, wearing them for too long, or not cleaning them properly can lead to intolerance. (360eyecare.ca)
  • Fortunately, modern day extended wear contact lenses are made from advanced hydrogel material i.e. silicone. (uniqso.com)
  • The lens diameter (DIA) specifies the overall size of the lens and, along with the base curve, determines how the lens fits. (allaboutvision.com)
  • Identify the risk factors for AK among contact lens users. (cdc.gov)
  • Many parents do not consider contact lenses for their children, but it is clear that children can learn proper hygiene for contact lenses. (larsonvisioncare.com)
  • This same effect was not found in patients who had worn soft contact lenses for an extended period of time. (wikipedia.org)
  • On May 26, 2007, the company voluntarily re- occurs primarily among users of soft contact lenses ( 5 ), called AMOCMP from domestic and international markets. (cdc.gov)
  • Soft contacts are the most common type of contact lenses and account for over 85% of contact lenses dispensed. (polkcityeyecare.com)
  • Traditional soft contact lenses consist of soft plastic polymers and water. (polkcityeyecare.com)
  • Most people find soft contact lenses comfortable. (polkcityeyecare.com)
  • One advantage of soft contacts is that people assimilate to them almost right away. (polkcityeyecare.com)
  • Soft lenses come in different prescriptions and designs depending on your budget and need. (polkcityeyecare.com)
  • Disposable contact lenses are soft lenses that are discarded on a daily, weekly, bi-weekly, or monthly basis. (polkcityeyecare.com)
  • Tinted contact lenses are soft lenses that enable some patients to change the color of their iris (the colored part of the eye). (polkcityeyecare.com)
  • Before the introduction of soft contact lenses, hard polymethyl methacrylate contact lenses were common. (polkcityeyecare.com)
  • This means they offer sharper vision than soft contacts. (polkcityeyecare.com)
  • They are much more durable than soft lenses. (polkcityeyecare.com)
  • Because they do not contain water, proteins and lipids do not adhere to them like they can do with soft lenses. (polkcityeyecare.com)
  • They are not immediately comfortable like soft lenses. (polkcityeyecare.com)
  • They are smaller in size so they can dislodge from the eye more easily than soft lenses. (polkcityeyecare.com)
  • Soft contacts are the most common choice for contact lenses. (larsonvisioncare.com)
  • Over 85% of all lenses are soft. (larsonvisioncare.com)
  • Traditional soft contact lenses are made of soft plastic polymers and water. (larsonvisioncare.com)
  • These soft lenses give you a unique look by changing your eye color. (larsonvisioncare.com)
  • Be warned that they are not as comfortable as soft lenses. (larsonvisioncare.com)
  • Because bifocals are more complicated than typical soft lenses, they require more time from the doctor for fitting. (larsonvisioncare.com)
  • Bestselling brands, such as Air Optix and Biofinity have been designed to be worn for a week without needing to be removed, while Air Optix Night & Day Aqua are unique lenses designed and approved for up to 30 days of continuous wear after your optician recommends. (feelgoodcontacts.com)
  • Microorganisms grow in warm & humid surface- contact lenses create a favorable condition for the growth of microbes when eyes are shut during sleep. (uniqso.com)
  • People with sensitive eyes are suggested to opt for disposable contact lenses since failing to keep your contacts clean may add to the risks involved. (uniqso.com)
  • They are significantly different because eyeglass lenses are positioned approximately 12 millimeters from your eyes and contact lenses rest directly on the surface of your eyes. (allaboutvision.com)
  • You will need to revisit your eye care professional when your prescription expires to check the health of your eyes before you can purchase additional lenses. (allaboutvision.com)
  • Conditions such as dry eyes and blepharitis can make contact lens wear uncomfortable and/or unsafe. (allaboutvision.com)
  • A contact lens fitting and a prescription written by a licensed eye care professional are required even if you have no need for vision correction and want only 'non-prescription' (plano) coloured contact lenses or special-effect contact lenses to change the appearance of your eyes. (allaboutvision.com)
  • These recommendations will help extend the life of your contact lenses and keep your eyes safe and healthy. (communityeye.com)
  • Remove your contact lenses immediately if your eyes become irritated. (communityeye.com)
  • Be sure to call us if you have any questions about caring for your contact lenses or if you're eyes are having problems. (communityeye.com)
  • Prioritize washing your hands with soap and running water before touching your eyes or lenses. (360eyecare.ca)
  • Different products may not be compatible with your lenses or eyes. (360eyecare.ca)
  • Our colored eye contacts are designed to make your eyes stand out and leave a lasting impression. (freshtone.shop)
  • Our lenses are designed to fit your eyes perfectly and enhance your natural beauty, leaving you feeling confident and beautiful every time you wear them. (freshtone.shop)
  • For anyone who wishes to buy cosmetic lenses like these, it's advisable for your eyes to be measured for a "plano" prescription, meaning one with zero vision correction. (alensa.com.mt)
  • Instructions for hygiene and handling lenses must be strictly observed. (msdmanuals.com)
  • A contact lens, regardless of whether it is used for vision correction or cosmetic purposes, is a medical device, and should only be purchased from a licensed retailer with a valid prescription. (allaboutvision.com)
  • However, these lenses are more pliable and more comfortable than the outdated hard lenses. (larsonvisioncare.com)
  • These lenses are made from high-quality materials that ensure extended comfort during daily wear. (honeycolor.com)
  • Contact lens-related abrasions are defects in the corneal epithelium that are left behind after the removal of an overworn, improperly fitting, or improperly cleaned contact lens. (medscape.com)
  • A lens is improperly inserted or removed. (msdmanuals.com)
  • The diameter is the width of the contact lens (measured in millimeters). (lentiamo.co.uk)
  • Diameter impacts the fit, comfort and functionality of your lenses. (lentiamo.co.uk)
  • CLI is a broad term describing the inability to wear contact lenses comfortably. (360eyecare.ca)
  • A professional measurement beforehand will also tell you which lenses should comfortably fit you, and which lenses won't. (alensa.com.mt)
  • Corneal sensitivity is significantly diminished after extended contact lens wear (five or more years). (wikipedia.org)
  • Prophylactic topical antibiotics are given in patients with abrasions from contact lenses, who are at increased risk for infected corneal ulcers, but many emergency physicians have stopped using these agents for minor injuries. (medscape.com)
  • Cases of contact lens-associated corneal ulcers are devastating to affected patients and practitioners and injurious to our industry. (clspectrum.com)
  • The two most common predisposing factors in the Philadelphia study were chronic surface disease (41.7 percent) and contact lens wear (29.2 percent). (clspectrum.com)
  • The lenses themselves are non-organic" explains Glenn "and bugs can stick to their surface causing eye infections, especially during extended use. (londonvisionclinic.com)
  • Lightly rubbing your contact in the palm of your hand with a few drops of solution helps remove surface build-up. (communityeye.com)
  • With something as sensitive as the eye, placing circuitry on the exterior surface of a contact lens comes with some mighty technical challenges. (zdnet.com)
  • In overwear syndrome or any other condition in which pain does not quickly resolve when lenses are removed, an ophthalmologist or optometrist should be consulted before lenses are worn again. (msdmanuals.com)
  • It is dedicated to providing customers with unique lenses in a multitude of patterns and shades to fit each individual lifestyle and need. (alensa.com.mt)
  • As Low As $86.95 Extended Wear: Monthly Replacement, Multi-Packaged Spherical, Light blue handling tint, 6-Pack, Water: 36%, Material: Balafilicon A. (contactlens.com)
  • Always follow the recommended contact lens replacement and wearing schedule prescribed. (communityeye.com)
  • Guaranteed replacement lenses if you change the prescription. (lentiamo.co.uk)
  • Usually EW contact lenses are preferred by patients as it involves less daily care but they add up to the troubles when become exposed to smoke, fumes & pollution in the open environment. (uniqso.com)
  • But a contact lens prescription cannot be written until your eye care professional performs a contact lens fitting or has access to your previous prescription and has evaluated the fit of your current lenses. (allaboutvision.com)
  • Ask us if you have questions about how to care for your contacts and case or if you are having any difficulties. (communityeye.com)
  • Some contacts need special care and products. (communityeye.com)
  • Do not change your lens care products without consulting your eye doctor first. (360eyecare.ca)
  • The products you use to care for your lenses can contribute to intolerance. (360eyecare.ca)
  • Always follow your doctor's instructions for lens wear and care. (360eyecare.ca)
  • How to Take Care of Yearly Colored Contact Lenses? (alensa.com.mt)
  • Yearly colored contact lenses require special care. (alensa.com.mt)
  • If you take proper care of your lenses, you can use them for the entire 365 days. (alensa.com.mt)
  • The countdown for lens care begins after the first wear. (alensa.com.mt)
  • In simple terms, you must provide regular care for the lenses through mechanical cleaning and storing them in a fresh solution. (alensa.com.mt)
  • Before you handle contacts, wash and rinse your hands with a mild soap. (communityeye.com)
  • Rub and rinse your contact lens case with sterile contact lens solution. (communityeye.com)
  • Rinse the mechanically cleaned lens with a fresh dose of solution and then store it in a case with a fresh dose of solution. (alensa.com.mt)
  • Annual lenses are durable lenses with a usability time-frame of 365 days. (alensa.com.mt)