An imaging method using LASERS that is used for mapping subsurface structure. When a reflective site in the sample is at the same optical path length (coherence) as the reference mirror, the detector observes interference fringes.
Tomography using x-ray transmission and a computer algorithm to reconstruct the image.
Imaging methods that result in sharp images of objects located on a chosen plane and blurred images located above or below the plane.
An oval area in the retina, 3 to 5 mm in diameter, usually located temporal to the posterior pole of the eye and slightly below the level of the optic disk. It is characterized by the presence of a yellow pigment diffusely permeating the inner layers, contains the fovea centralis in its center, and provides the best phototropic visual acuity. It is devoid of retinal blood vessels, except in its periphery, and receives nourishment from the choriocapillaris of the choroid. (From Cline et al., Dictionary of Visual Science, 4th ed)
Methods and procedures for the diagnosis of diseases of the eye or of vision disorders.
A view of the world and the individual's environment as comprehensible, manageable, and meaningful, claiming that the way people view their life has a positive influence on their health.
Slender processes of NEURONS, including the AXONS and their glial envelopes (MYELIN SHEATH). Nerve fibers conduct nerve impulses to and from the CENTRAL NERVOUS SYSTEM.
The portion of the optic nerve seen in the fundus with the ophthalmoscope. It is formed by the meeting of all the retinal ganglion cell axons as they enter the optic nerve.
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.
Visualization of a vascular system after intravenous injection of a fluorescein solution. The images may be photographed or televised. It is used especially in studying the retinal and uveal vasculature.
Fluid accumulation in the outer layer of the MACULA LUTEA that results from intraocular or systemic insults. It may develop in a diffuse pattern where the macula appears thickened or it may acquire the characteristic petaloid appearance referred to as cystoid macular edema. Although macular edema may be associated with various underlying conditions, it is most commonly seen following intraocular surgery, venous occlusive disease, DIABETIC RETINOPATHY, and posterior segment inflammatory disease. (From Survey of Ophthalmology 2004; 49(5) 470-90)
Neurons of the innermost layer of the retina, the internal plexiform layer. They are of variable sizes and shapes, and their axons project via the OPTIC NERVE to the brain. A small subset of these cells act as photoreceptors with projections to the SUPRACHIASMATIC NUCLEUS, the center for regulating CIRCADIAN RHYTHM.
The ten-layered nervous tissue membrane of the eye. It is continuous with the OPTIC NERVE and receives images of external objects and transmits visual impulses to the brain. Its outer surface is in contact with the CHOROID and the inner surface with the VITREOUS BODY. The outer-most layer is pigmented, whereas the inner nine layers are transparent.
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).
Conditions which produce injury or dysfunction of the second cranial or optic nerve, which is generally considered a component of the central nervous system. Damage to optic nerve fibers may occur at or near their origin in the retina, at the optic disk, or in the nerve, optic chiasm, optic tract, or lateral geniculate nuclei. Clinical manifestations may include decreased visual acuity and contrast sensitivity, impaired color vision, and an afferent pupillary defect.
Analysis based on the mathematical function first formulated by Jean-Baptiste-Joseph Fourier in 1807. The function, known as the Fourier transform, describes the sinusoidal pattern of any fluctuating pattern in the physical world in terms of its amplitude and its phase. It has broad applications in biomedicine, e.g., analysis of the x-ray crystallography data pivotal in identifying the double helical nature of DNA and in analysis of other molecules, including viruses, and the modified back-projection algorithm universally used in computerized tomography imaging, etc. (From Segen, The Dictionary of Modern Medicine, 1992)
Examination of the interior of the eye with an ophthalmoscope.
LIGHT, it's processes and properties, and the characteristics of materials interacting with it.
An area approximately 1.5 millimeters in diameter within the macula lutea where the retina thins out greatly because of the oblique shifting of all layers except the pigment epithelium layer. It includes the sloping walls of the fovea (clivus) and contains a few rods in its periphery. In its center (foveola) are the cones most adapted to yield high visual acuity, each cone being connected to only one ganglion cell. (Cline et al., Dictionary of Visual Science, 4th ed)
The process of generating three-dimensional images by electronic, photographic, or other methods. For example, three-dimensional images can be generated by assembling multiple tomographic images with the aid of a computer, while photographic 3-D images (HOLOGRAPHY) can be made by exposing film to the interference pattern created when two laser light sources shine on an object.
The front third of the eyeball that includes the structures between the front surface of the cornea and the front of the VITREOUS BODY.
The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.
The concave interior of the eye, consisting of the retina, the choroid, the sclera, the optic disk, and blood vessels, seen by means of the ophthalmoscope. (Cline et al., Dictionary of Visual Science, 4th ed)
An ocular disease, occurring in many forms, having as its primary characteristics an unstable or a sustained increase in the intraocular pressure which the eye cannot withstand without damage to its structure or impairment of its function. The consequences of the increased pressure may be manifested in a variety of symptoms, depending upon type and severity, such as excavation of the optic disk, hardness of the eyeball, corneal anesthesia, reduced visual acuity, seeing of colored halos around lights, disturbed dark adaptation, visual field defects, and headaches. (Dictionary of Visual Science, 4th ed)
An imaging technique using compounds labelled with short-lived positron-emitting radionuclides (such as carbon-11, nitrogen-13, oxygen-15 and fluorine-18) to measure cell metabolism. It has been useful in study of soft tissues such as CANCER; CARDIOVASCULAR SYSTEM; and brain. SINGLE-PHOTON EMISSION-COMPUTED TOMOGRAPHY is closely related to positron emission tomography, but uses isotopes with longer half-lives and resolution is lower.
The thin, highly vascular membrane covering most of the posterior of the eye between the RETINA and SCLERA.
Perforations through the whole thickness of the retina including the macula as the result of inflammation, trauma, degeneration, etc. The concept includes retinal breaks, tears, dialyses, and holes.
Method of measuring and mapping the scope of vision, from central to peripheral of each eye.
Examination of the angle of the anterior chamber of the eye with a specialized optical instrument (gonioscope) or a contact prism lens.
A membrane on the vitreal surface of the retina resulting from the proliferation of one or more of three retinal elements: (1) fibrous astrocytes; (2) fibrocytes; and (3) retinal pigment epithelial cells. Localized epiretinal membranes may occur at the posterior pole of the eye without clinical signs or may cause marked loss of vision as a result of covering, distorting, or detaching the fovea centralis. Epiretinal membranes may cause vascular leakage and secondary retinal edema. In younger individuals some membranes appear to be developmental in origin and occur in otherwise normal eyes. The majority occur in association with retinal holes, ocular concussions, retinal inflammation, or after ocular surgery. (Newell, Ophthalmology: Principles and Concepts, 7th ed, p291)
Descriptive anatomy based on three-dimensional imaging (IMAGING, THREE-DIMENSIONAL) of the body, organs, and structures using a series of computer multiplane sections, displayed by transverse, coronal, and sagittal analyses. It is essential to accurate interpretation by the radiologist of such techniques as ultrasonic diagnosis, MAGNETIC RESONANCE IMAGING, and computed tomography (TOMOGRAPHY, X-RAY COMPUTED). (From Lane & Sharfaei, Modern Sectional Anatomy, 1992, Preface)
Methods of creating machines and devices.
The total area or space visible in a person's peripheral vision with the eye looking straightforward.
The light sensitive outer portion of a retinal rod or a cone photoreceptor cell. The outer segment contains a stack of disk membranes laden with photoreceptive pigments (RETINAL PIGMENTS). The outer segment is connected to the inner segment by a PHOTORECEPTOR CONNECTING CILIUM.
Measurement of the thickness of the CORNEA.
The single layer of pigment-containing epithelial cells in the RETINA, situated closely to the tips (outer segments) of the RETINAL PHOTORECEPTOR CELLS. These epithelial cells are macroglia that perform essential functions for the photoreceptor cells, such as in nutrient transport, phagocytosis of the shed photoreceptor membranes, and ensuring retinal attachment.
The inner portion of a retinal rod or a cone photoreceptor cell, situated between the PHOTORECEPTOR CONNECTING CILIUM and the synapse with the adjacent neurons (RETINAL BIPOLAR CELLS; RETINAL HORIZONTAL CELLS). The inner segment contains the cell body, the nucleus, the mitochondria, and apparatus for protein synthesis.
Tomography using radioactive emissions from injected RADIONUCLIDES and computer ALGORITHMS to reconstruct an image.
Projection of near-IR light (INFRARED RAYS), in the 700-1000 nm region, across an object in parallel beams to an array of sensitive photodetectors. This is repeated at various angles and a mathematical reconstruction provides three dimensional MEDICAL IMAGING of tissues. Based on the relative transparency of tissues to this spectra, it has been used to monitor local oxygenation, brain and joints.
The new and thickened layer of scar tissue that forms on a PROSTHESIS, or as a result of vessel injury especially following ANGIOPLASTY or stent placement.
A scientific tool based on ULTRASONOGRAPHY and used not only for the observation of microstructure in metalwork but also in living tissue. In biomedical application, the acoustic propagation speed in normal and abnormal tissues can be quantified to distinguish their tissue elasticity and other properties.
Improvement of the quality of a picture by various techniques, including computer processing, digital filtering, echocardiographic techniques, light and ultrastructural MICROSCOPY, fluorescence spectrometry and microscopy, scintigraphy, and in vitro image processing at the molecular level.
Devices for examining the interior of the eye, permitting the clear visualization of the structures of the eye at any depth. (UMDNS, 1999)
Disorders of the choroid including hereditary choroidal diseases, neoplasms, and other abnormalities of the vascular layer of the uvea.
Degenerative changes in the RETINA usually of older adults which results in a loss of vision in the center of the visual field (the MACULA LUTEA) because of damage to the retina. It occurs in dry and wet forms.
The pressure of the fluids in the eye.
Detachment of the corpus vitreum (VITREOUS BODY) from its normal attachments, especially the retina, due to shrinkage from degenerative or inflammatory conditions, trauma, myopia, or senility.
Computed tomography where there is continuous X-ray exposure to the patient while being transported in a spiral or helical pattern through the beam of irradiation. This provides improved three-dimensional contrast and spatial resolution compared to conventional computed tomography, where data is obtained and computed from individual sequential exposures.
A specialized field of physics and engineering involved in studying the behavior and properties of light and the technology of analyzing, generating, transmitting, and manipulating ELECTROMAGNETIC RADIATION in the visible, infrared, and ultraviolet range.
The evaluation of incidents involving the loss of function of a device. These evaluations are used for a variety of purposes such as to determine the failure rates, the causes of failures, costs of failures, and the reliability and maintainability of devices.
Instruments for RETINOSCOPY that determines the refractive state of the EYE, such as the degree of NEARSIGHTEDNESS; FARSIGHTEDNESS; or ASTIGMATISM. In principle, a retinoscope provides a light source to illuminate the RETINA, and then locates the aerial image of the retina in space to obtain an index of the refractive quality of the patient's lens system.
Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)
The distance between the anterior and posterior poles of the eye, measured either by ULTRASONOGRAPHY or by partial coherence interferometry.
Separation of the inner layers of the retina (neural retina) from the pigment epithelium. Retinal detachment occurs more commonly in men than in women, in eyes with degenerative myopia, in aging and in aphakia. It may occur after an uncomplicated cataract extraction, but it is seen more often if vitreous humor has been lost during surgery. (Dorland, 27th ed; Newell, Ophthalmology: Principles and Concepts, 7th ed, p310-12).
An exudate between the RETINA and CHOROID from various sources including the vitreous cavity, SUBARACHNOID SPACE, or abnormal vessels.
Excessive axial myopia associated with complications (especially posterior staphyloma and CHOROIDAL NEOVASCULARIZATION) that can lead to BLINDNESS.
A technique of inputting two-dimensional images into a computer and then enhancing or analyzing the imagery into a form that is more useful to the human observer.
Measurement of the index of refraction (the ratio of the velocity of light or other radiation in the first of two media to its velocity in the second as it passes from one into the other).
Disease of the RETINA as a complication of DIABETES MELLITUS. It is characterized by the progressive microvascular complications, such as ANEURYSM, interretinal EDEMA, and intraocular PATHOLOGIC NEOVASCULARIZATION.
A vitreoretinal dystrophy characterized by splitting of the neuroretinal layers. It occurs in two forms: degenerative retinoschisis and X chromosome-linked juvenile retinoschisis.
Recording of electric potentials in the retina after stimulation by light.
Optic disk bodies composed primarily of acid mucopolysaccharides that may produce pseudopapilledema (elevation of the optic disk without associated INTRACRANIAL HYPERTENSION) and visual field deficits. Drusen may also occur in the retina (see RETINAL DRUSEN). (Miller et al., Clinical Neuro-Ophthalmology, 4th ed, p355)
Method of making images on a sensitized surface by exposure to light or other radiant energy.
The space in the eye, filled with aqueous humor, bounded anteriorly by the cornea and a small portion of the sclera and posteriorly by a small portion of the ciliary body, the iris, and that part of the crystalline lens which presents through the pupil. (Cline et al., Dictionary of Visual Science, 4th ed, p109)
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)
Glaucoma in which the angle of the anterior chamber is open and the trabecular meshwork does not encroach on the base of the iris.
A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task.
Colloid or hyaline bodies lying beneath the retinal pigment epithelium. They may occur either secondary to changes in the choroid that affect the pigment epithelium or as an autosomal dominant disorder of the retinal pigment epithelium.
The use of ultrasound to guide minimally invasive surgical procedures such as needle ASPIRATION BIOPSY; DRAINAGE; etc. Its widest application is intravascular ultrasound imaging but it is useful also in urology and intra-abdominal conditions.
A pathological process consisting of the formation of new blood vessels in the CHOROID.
Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.
Removal of the whole or part of the vitreous body in treating endophthalmitis, diabetic retinopathy, retinal detachment, intraocular foreign bodies, and some types of glaucoma.
Types of spiral computed tomography technology in which multiple slices of data are acquired simultaneously improving the resolution over single slice acquisition technology.
Nerve cells of the RETINA in the pathway of transmitting light signals to the CENTRAL NERVOUS SYSTEM. They include the outer layer of PHOTORECEPTOR CELLS, the intermediate layer of RETINAL BIPOLAR CELLS and AMACRINE CELLS, and the internal layer of RETINAL GANGLION CELLS.
Instruments for the visual examination of interior structures of the body. There are rigid endoscopes and flexible fiberoptic endoscopes for various types of viewing in ENDOSCOPY.
Specialized PHOTOTRANSDUCTION neurons in the vertebrates, such as the RETINAL ROD CELLS and the RETINAL CONE CELLS. Non-visual photoreceptor neurons have been reported in the deep brain, the PINEAL GLAND and organs of the circadian system.
The administration of substances into the VITREOUS BODY of the eye with a hypodermic syringe.
Thin strands of transparent material, usually glass, that are used for transmitting light waves over long distances.
General disorders of the sclera or white of the eye. They may include anatomic, embryologic, degenerative, or pigmentation defects.
Methods developed to aid in the interpretation of ultrasound, radiographic images, etc., for diagnosis of disease.
The transparent, semigelatinous substance that fills the cavity behind the CRYSTALLINE LENS of the EYE and in front of the RETINA. It is contained in a thin hyaloid membrane and forms about four fifths of the optic globe.
A method of computed tomography that uses radionuclides which emit a single photon of a given energy. The camera is rotated 180 or 360 degrees around the patient to capture images at multiple positions along the arc. The computer is then used to reconstruct the transaxial, sagittal, and coronal images from the 3-dimensional distribution of radionuclides in the organ. The advantages of SPECT are that it can be used to observe biochemical and physiological processes as well as size and volume of the organ. The disadvantage is that, unlike positron-emission tomography where the positron-electron annihilation results in the emission of 2 photons at 180 degrees from each other, SPECT requires physical collimation to line up the photons, which results in the loss of many available photons and hence degrades the image.
A form of glaucoma in which the intraocular pressure increases because the angle of the anterior chamber is blocked and the aqueous humor cannot drain from the anterior chamber.
Pieces of glass or other transparent materials used for magnification or increased visual acuity.
A form of MACULAR DEGENERATION also known as dry macular degeneration marked by occurrence of a well-defined progressive lesion or atrophy in the central part of the RETINA called the MACULA LUTEA. It is distinguishable from WET MACULAR DEGENERATION in that the latter involves neovascular exudates.
Visual impairments limiting one or more of the basic functions of the eye: visual acuity, dark adaptation, color vision, or peripheral vision. These may result from EYE DISEASES; OPTIC NERVE DISEASES; VISUAL PATHWAY diseases; OCCIPITAL LOBE diseases; OCULAR MOTILITY DISORDERS; and other conditions (From Newell, Ophthalmology: Principles and Concepts, 7th ed, p132).
An objective determination of the refractive state of the eye (NEARSIGHTEDNESS; FARSIGHTEDNESS; ASTIGMATISM). By using a RETINOSCOPE, the amount of correction and the power of lens needed can be determined.
Computed tomography modalities which use a cone or pyramid-shaped beam of radiation.
A tomographic technique for obtaining 3-dimensional images with transmission electron microscopy.
An optical source that emits photons in a coherent beam. Light Amplification by Stimulated Emission of Radiation (LASER) is brought about using devices that transform light of varying frequencies into a single intense, nearly nondivergent beam of monochromatic radiation. Lasers operate in the infrared, visible, ultraviolet, or X-ray regions of the spectrum.
Changes in the observed frequency of waves (as sound, light, or radio waves) due to the relative motion of source and observer. The effect was named for the 19th century Austrian physicist Johann Christian Doppler.
Measurements of the height, weight, length, area, etc., of the human and animal body or its parts.
The veins and arteries of the HEART.
Devices or objects in various imaging techniques used to visualize or enhance visualization by simulating conditions encountered in the procedure. Phantoms are used very often in procedures employing or measuring x-irradiation or radioactive material to evaluate performance. Phantoms often have properties similar to human tissue. Water demonstrates absorbing properties similar to normal tissue, hence water-filled phantoms are used to map radiation levels. Phantoms are used also as teaching aids to simulate real conditions with x-ray or ultrasonic machines. (From Iturralde, Dictionary and Handbook of Nuclear Medicine and Clinical Imaging, 1990)
The failure by the observer to measure or identify a phenomenon accurately, which results in an error. Sources for this may be due to the observer's missing an abnormality, or to faulty technique resulting in incorrect test measurement, or to misinterpretation of the data. Two varieties are inter-observer variation (the amount observers vary from one another when reporting on the same material) and intra-observer variation (the amount one observer varies between observations when reporting more than once on the same material).
The 2nd cranial nerve which conveys visual information from the RETINA to the brain. The nerve carries the axons of the RETINAL GANGLION CELLS which sort at the OPTIC CHIASM and continue via the OPTIC TRACTS to the brain. The largest projection is to the lateral geniculate nuclei; other targets include the SUPERIOR COLLICULI and the SUPRACHIASMATIC NUCLEI. Though known as the second cranial nerve, it is considered part of the CENTRAL NERVOUS SYSTEM.
The use of green light-producing LASERS to stop bleeding. The green light is selectively absorbed by HEMOGLOBIN, thus triggering BLOOD COAGULATION.
A visual impairment characterized by the accumulation of fluid under the retina through a defect in the retinal pigment epithelium.
A technique of diagnostic imaging of RETINA or CORNEA of the human eye involving the measurement and interpretation of polarizing ELECTROMAGNETIC WAVES such as radio or light waves. It is helpful in the diagnosis of GLAUCOMA; MACULAR DEGENERATION; and other retinal disorders.
Measurement of ocular tension (INTRAOCULAR PRESSURE) with a tonometer. (Cline, et al., Dictionary of Visual Science, 4th ed)
The use of statistical and mathematical methods to analyze biological observations and phenomena.
A condition in which the intraocular pressure is elevated above normal and which may lead to glaucoma.
Any visual display of structural or functional patterns of organs or tissues for diagnostic evaluation. It includes measuring physiologic and metabolic responses to physical and chemical stimuli, as well as ultramicroscopy.
Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.
Stents that are covered with materials that are embedded with chemicals that are gradually released into the surrounding milieu.
The property of nonisotropic media, such as crystals, whereby a single incident beam of light traverses the medium as two beams, each plane-polarized, the planes being at right angles to each other. (Cline et al., Dictionary of Visual Science, 4th ed)
Any visible result of a procedure which is caused by the procedure itself and not by the entity being analyzed. Common examples include histological structures introduced by tissue processing, radiographic images of structures that are not naturally present in living tissue, and products of chemical reactions that occur during analysis.
The administration of substances into the eye with a hypodermic syringe.
Studies in which individuals or populations are followed to assess the outcome of exposures, procedures, or effects of a characteristic, e.g., occurrence of disease.
Inflammation of the optic nerve. Commonly associated conditions include autoimmune disorders such as MULTIPLE SCLEROSIS, infections, and granulomatous diseases. Clinical features include retro-orbital pain that is aggravated by eye movement, loss of color vision, and contrast sensitivity that may progress to severe visual loss, an afferent pupillary defect (Marcus-Gunn pupil), and in some instances optic disc hyperemia and swelling. Inflammation may occur in the portion of the nerve within the globe (neuropapillitis or anterior optic neuritis) or the portion behind the globe (retrobulbar neuritis or posterior optic neuritis).
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.
Atrophy of the optic disk which may be congenital or acquired. This condition indicates a deficiency in the number of nerve fibers which arise in the RETINA and converge to form the OPTIC DISK; OPTIC NERVE; OPTIC CHIASM; and optic tracts. GLAUCOMA; ISCHEMIA; inflammation, a chronic elevation of intracranial pressure, toxins, optic nerve compression, and inherited conditions (see OPTIC ATROPHIES, HEREDITARY) are relatively common causes of this condition.
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.
A tricarbocyanine dye that is used diagnostically in liver function tests and to determine blood volume and cardiac output.
A form of RETINAL DEGENERATION in which abnormal CHOROIDAL NEOVASCULARIZATION occurs under the RETINA and MACULA LUTEA, causing bleeding and leaking of fluid. This leads to bulging and or lifting of the macula and the distortion or destruction of central vision.
Tomography using x-ray transmission.
Pathological processes of CORONARY ARTERIES that may derive from a congenital abnormality, atherosclerotic, or non-atherosclerotic cause.
The blood vessels which supply and drain the RETINA.
In screening and diagnostic tests, the probability that a person with a positive test is a true positive (i.e., has the disease), is referred to as the predictive value of a positive test; whereas, the predictive value of a negative test is the probability that the person with a negative test does not have the disease. Predictive value is related to the sensitivity and specificity of the test.
Implants constructed of materials designed to be absorbed by the body without producing an immune response. They are usually composed of plastics and are frequently used in orthopedics and orthodontics.
A group of disorders involving predominantly the posterior portion of the ocular fundus, due to degeneration in the sensory layer of the RETINA; RETINAL PIGMENT EPITHELIUM; BRUCH MEMBRANE; CHOROID; or a combination of these tissues.
The most anterior portion of the uveal layer, separating the anterior chamber from the posterior. It consists of two layers - the stroma and the pigmented epithelium. Color of the iris depends on the amount of melanin in the stroma on reflection from the pigmented epithelium.
Hereditary, progressive degeneration of the neuroepithelium of the retina characterized by night blindness and progressive contraction of the visual field.
The technology of transmitting light over long distances through strands of glass or other transparent material.
Lesions formed within the walls of ARTERIES.
An esterified form of TRIAMCINOLONE. It is an anti-inflammatory glucocorticoid used topically in the treatment of various skin disorders. Intralesional, intramuscular, and intra-articular injections are also administered under certain conditions.
Surgical removal of a section of the iris.
A retrogressive pathological change in the retina, focal or generalized, caused by genetic defects, inflammation, trauma, vascular disease, or aging. Degeneration affecting predominantly the macula lutea of the retina is MACULAR DEGENERATION. (Newell, Ophthalmology: Principles and Concepts, 7th ed, p304)
The use of instrumentation and techniques for visualizing material and details that cannot be seen by the unaided eye. It is usually done by enlarging images, transmitted by light or electron beams, with optical or magnetic lenses that magnify the entire image field. With scanning microscopy, images are generated by collecting output from the specimen in a point-by-point fashion, on a magnified scale, as it is scanned by a narrow beam of light or electrons, a laser, a conductive probe, or a topographical probe.
Radiography of the vascular system of the heart muscle after injection of a contrast medium.
Refraction of LIGHT effected by the media of the EYE.
A surgical procedure or KERATOPLASTY involving selective stripping and replacement of diseased host DESCEMET MEMBRANE and CORNEAL ENDOTHELIUM with a suitable and healthy donor posterior lamella. The advantage to this procedure is that the normal corneal surface of the recipient is retained, thereby avoiding corneal surface incisions and sutures.
Studies to determine the advantages or disadvantages, practicability, or capability of accomplishing a projected plan, study, or project.
The white, opaque, fibrous, outer tunic of the eyeball, covering it entirely excepting the segment covered anteriorly by the cornea. It is essentially avascular but contains apertures for vessels, lymphatics, and nerves. It receives the tendons of insertion of the extraocular muscles and at the corneoscleral junction contains the canal of Schlemm. (From Cline et al., Dictionary of Visual Science, 4th ed)
Blockage of the RETINAL VEIN. Those at high risk for this condition include patients with HYPERTENSION; DIABETES MELLITUS; ATHEROSCLEROSIS; and other CARDIOVASCULAR DISEASES.
Elements of limited time intervals, contributing to particular results or situations.
An excessive amount of fluid in the cornea due to damage of the epithelium or endothelium causing decreased visual acuity.
Microscopy using polarized light in which phenomena due to the preferential orientation of optical properties with respect to the vibration plane of the polarized light are made visible and correlated parameters are made measurable.
Behavior of LIGHT and its interactions with itself and materials.
Specialized ophthalmic technique used in the surgical repair and or treatment of disorders that include retinal tears or detachment; MACULAR HOLES; hereditary retinal disease; AIDS-related retinal infections; ocular tumors; MACULAR DEGENERATION; DIABETIC RETINOPATHY; and UVEITIS.
A graphic means for assessing the ability of a screening test to discriminate between healthy and diseased persons; may also be used in other studies, e.g., distinguishing stimuli responses as to a faint stimuli or nonstimuli.
The compound is given by intravenous injection to do POSITRON-EMISSION TOMOGRAPHY for the assessment of cerebral and myocardial glucose metabolism in various physiological or pathological states including stroke and myocardial ischemia. It is also employed for the detection of malignant tumors including those of the brain, liver, and thyroid gland. (From Martindale, The Extra Pharmacopoeia, 30th ed, p1162)
Nonionic surfactant mixtures varying in the number of repeating ethoxy (oxy-1,2-ethanediyl) groups. They are used as detergents, emulsifiers, wetting agents, defoaming agents, etc. Nonoxynol-9, the compound with 9 repeating ethoxy groups, is a spermatocide, formulated primarily as a component of vaginal foams and creams.
Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.
The range or frequency distribution of a measurement in a population (of organisms, organs or things) that has not been selected for the presence of disease or abnormality.
A macrolide compound obtained from Streptomyces hygroscopicus that acts by selectively blocking the transcriptional activation of cytokines thereby inhibiting cytokine production. It is bioactive only when bound to IMMUNOPHILINS. Sirolimus is a potent immunosuppressant and possesses both antifungal and antineoplastic properties.
The use of computers for designing and/or manufacturing of anything, including drugs, surgical procedures, orthotics, and prosthetics.
Swelling of the OPTIC DISK, usually in association with increased intracranial pressure, characterized by hyperemia, blurring of the disk margins, microhemorrhages, blind spot enlargement, and engorgement of retinal veins. Chronic papilledema may cause OPTIC ATROPHY and visual loss. (Miller et al., Clinical Neuro-Ophthalmology, 4th ed, p175)
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)
A surgical procedure to correct MYOPIA by CORNEAL STROMA subtraction. It involves the use of a microkeratome to make a lamellar dissection of the CORNEA creating a flap with intact CORNEAL EPITHELIUM. After the flap is lifted, the underlying midstroma is reshaped with an EXCIMER LASER and the flap is returned to its original position.
X-ray image-detecting devices that make a focused image of body structures lying in a predetermined plane from which more complex images are computed.
Computer-assisted processing of electric, ultrasonic, or electronic signals to interpret function and activity.
Exudates are fluids, CELLS, or other cellular substances that are slowly discharged from BLOOD VESSELS usually from inflamed tissues. Transudates are fluids that pass through a membrane or squeeze through tissue or into the EXTRACELLULAR SPACE of TISSUES. Transudates are thin and watery and contain few cells or PROTEINS.
Studies in which the presence or absence of disease or other health-related variables are determined in each member of the study population or in a representative sample at one particular time. This contrasts with LONGITUDINAL STUDIES which are followed over a period of time.
The inner layer of CHOROID, also called the lamina basalis choroideae, located adjacent to the RETINAL PIGMENT EPITHELIUM; (RPE) of the EYE. It is a membrane composed of the basement membranes of the choriocapillaris ENDOTHELIUM and that of the RPE. The membrane stops at the OPTIC NERVE, as does the RPE.
Investigative and diagnostic methods and procedures based on the photoacoustic effect, which is the generation of SOUND WAVES from the absorption of ELECTROMAGNETIC RADIATION.
A procedure for removal of the crystalline lens in cataract surgery in which an anterior capsulectomy is performed by means of a needle inserted through a small incision at the temporal limbus, allowing the lens contents to fall through the dilated pupil into the anterior chamber where they are broken up by the use of ultrasound and aspirated out of the eye through the incision. (Cline, et al., Dictionary of Visual Science, 4th ed & In Focus 1993;1(1):1)
The diversion of RADIATION (thermal, electromagnetic, or nuclear) from its original path as a result of interactions or collisions with atoms, molecules, or larger particles in the atmosphere or other media. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Autosomal dominant hereditary maculopathy with childhood-onset accumulation of LIPOFUSION in RETINAL PIGMENT EPITHELIUM. Affected individuals develop progressive central acuity loss, and distorted vision (METAMORPHOPSIA). It is associated with mutations in bestrophin, a chloride channel.
Pathologic changes that occur in the axon and cell body of a neuron proximal to an axonal lesion. The process is characterized by central chromatolysis which features flattening and displacement of the nucleus, loss of Nissl bodies, and cellular edema. Central chromatolysis primarily occurs in lower motor neurons.
A layer of acellular matrix that lies beneath the CORNEAL EPITHELIUM and above the CORNEAL STROMA. It consists of randomly arranged COLLAGEN fibers in a condensed bed of intercellular substance. It provides stability and strength to the cornea.
Devices that provide support for tubular structures that are being anastomosed or for body cavities during skin grafting.
Agents that affect the rate or intensity of cardiac contraction, blood vessel diameter, or blood volume.
Coagulation of blood in any of the CORONARY VESSELS. The presence of a blood clot (THROMBUS) often leads to MYOCARDIAL INFARCTION.
The fluid secreted by the lacrimal glands. This fluid moistens the CONJUNCTIVA and CORNEA.
A localized defect in the visual field bordered by an area of normal vision. This occurs with a variety of EYE DISEASES (e.g., RETINAL DISEASES and GLAUCOMA); OPTIC NERVE DISEASES, and other conditions.
Surgical techniques on the CORNEA employing LASERS, especially for reshaping the CORNEA to correct REFRACTIVE ERRORS.
Production of a radiographic image of a small or very thin object on fine-grained photographic film under conditions which permit subsequent microscopic examination or enlargement of the radiograph at linear magnifications of up to several hundred and with a resolution approaching the resolving power of the photographic emulsion (about 1000 lines per millimeter).
A tooth's loss of minerals, such as calcium in hydroxyapatite from the tooth matrix, caused by acidic exposure. An example of the occurrence of demineralization is in the formation of dental caries.
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.
Recurrent narrowing or constriction of a coronary artery following surgical procedures performed to alleviate a prior obstruction.
Surgery performed on the eye or any of its parts.
Endoscopes for examining the interior of the esophagus.
Diagnostic tests conducted in order to measure the increment of active DENTAL CARIES over a period of time.
Narrowing or constriction of a coronary artery.
Dilation of an occluded coronary artery (or arteries) by means of a balloon catheter to restore myocardial blood supply.
A layer of the cornea. It is the basal lamina of the CORNEAL ENDOTHELIUM (from which it is secreted) separating it from the CORNEAL STROMA. It is a homogeneous structure composed of fine collagenous filaments, and slowly increases in thickness with age.
Small-scale tests of methods and procedures to be used on a larger scale if the pilot study demonstrates that these methods and procedures can work.
Levels within a diagnostic group which are established by various measurement criteria applied to the seriousness of a patient's disorder.
A form of GLAUCOMA in which chronic optic nerve damage and loss of vision normally attributable to buildup of intraocular pressure occurs despite prevailing conditions of normal intraocular pressure.
Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.
The plan and delineation of prostheses in general or a specific prosthesis.
A group of rare, idiopathic, congenital retinal vascular anomalies affecting the retinal capillaries. It is characterized by dilation and tortuosity of retinal vessels and formation of multiple aneurysms, with different degrees of leakage and exudates emanating from the blood vessels.
Ischemic injury to the OPTIC NERVE which usually affects the OPTIC DISK (optic neuropathy, anterior ischemic) and less frequently the retrobulbar portion of the nerve (optic neuropathy, posterior ischemic). The injury results from occlusion of arterial blood supply which may result from TEMPORAL ARTERITIS; ATHEROSCLEROSIS; COLLAGEN DISEASES; EMBOLISM; DIABETES MELLITUS; and other conditions. The disease primarily occurs in the sixth decade or later and presents with the sudden onset of painless and usually severe monocular visual loss. Anterior ischemic optic neuropathy also features optic disk edema with microhemorrhages. The optic disk appears normal in posterior ischemic optic neuropathy. (Glaser, Neuro-Ophthalmology, 2nd ed, p135)
Endoscopic examination, therapy or surgery performed on the interior of blood vessels.
Introduction of substances into the body using a needle and syringe.
That portion of the electromagnetic spectrum usually sensed as heat. Infrared wavelengths are longer than those of visible light, extending into the microwave frequencies. They are used therapeutically as heat, and also to warm food in restaurants.
Substances used to allow enhanced visualization of tissues.
Tear or break of an organ, vessel or other soft part of the body, occurring in the absence of external force.
Agents and endogenous substances that antagonize or inhibit the development of new blood vessels.
The comparison of the quantity of meaningful data to the irrelevant or incorrect data.
Photosensitive afferent neurons located primarily within the FOVEA CENTRALIS of the MACULA LUTEA. There are three major types of cone cells (red, blue, and green) whose photopigments have different spectral sensitivity curves. Retinal cone cells operate in daylight vision (at photopic intensities) providing color recognition and central visual acuity.
The X-shaped structure formed by the meeting of the two optic nerves. At the optic chiasm the fibers from the medial part of each retina cross to project to the other side of the brain while the lateral retinal fibers continue on the same side. As a result each half of the brain receives information about the contralateral visual field from both eyes.
The aperture in the iris through which light passes.
The protrusion of an organ or part of an organ into a natural or artificial orifice.
That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.
Permanent dilation of preexisting blood vessels (CAPILLARIES; ARTERIOLES; VENULES) creating small focal red lesions, most commonly in the skin or mucous membranes. It is characterized by the prominence of skin blood vessels, such as vascular spiders.
A family of percutaneous techniques that are used to manage CORONARY OCCLUSION, including standard balloon angioplasty (PERCUTANEOUS TRANSLUMINAL CORONARY ANGIOPLASTY), the placement of intracoronary STENTS, and atheroablative technologies (e.g., ATHERECTOMY; ENDARTERECTOMY; THROMBECTOMY; PERCUTANEOUS TRANSLUMINAL LASER ANGIOPLASTY). PTCA was the dominant form of PCI, before the widespread use of stenting.
Chemical substances that are destructive to spermatozoa used as topically administered vaginal contraceptives.
Transmission of gene defects or chromosomal aberrations/abnormalities which are expressed in extreme variation in the structure or function of the eye. These may be evident at birth, but may be manifested later with progression of the disorder.
An X chromosome-linked abnormality characterized by atrophy of the choroid and degeneration of the retinal pigment epithelium causing night blindness.

Intravascular modalities for detection of vulnerable plaque: current status. (1/2999)

Progress in the diagnosis, treatment, and prevention of atherosclerotic coronary artery disease is dependent on a greater understanding of the mechanisms of coronary plaque progression. Autopsy studies have characterized a subgroup of high-risk, or vulnerable, plaques that result in acute coronary syndromes or sudden cardiac death. These angiographically modest plaques share certain pathologic characteristics: a thin, fibrous cap, lipid-rich core, and macrophage activity. Diagnostic techniques for vulnerable-plaque detection, including serologic markers and noninvasive and invasive techniques, are needed. Recent advances in intravascular imaging have significantly improved the ability to detect high-risk, or vulnerable, plaque in vivo by using various features of plaque vulnerability as methods of identification. The characteristic anatomy of a thin, fibrous cap overlying a lipid pool has promoted high-resolution imaging, such as intravascular ultrasound, optical coherence tomography, and intracoronary magnetic resonance. The lipid-rich core is identifiable by angioscopically detected color changes on the plaque surface or by its unique absorption of energy, or "Raman shift," of its cholesterol core, driving coronary spectroscopy. Finally, temperature heterogeneity arising at foci of plaque inflammation has prompted the development of intracoronary thermography. In this review, we will discuss these techniques, their relative advantages and limitations, and their potential clinical application.  (+info)

Choroidal neovascularization characteristics and its size in optical coherence tomography. (2/2999)

The classification, size and activity of choroidal neovascularization (CNV) by optical coherence tomography (OCT) were compared with those obtained by fluorescein angiography (FA) and Indocyanine green angiography (ICG). This study included 32 patients (32 eyes) diagnosed as having CNV. The etiology of CNV was found to be age-related macular degeneration (AMD) or non-AMD. Patients were studied retrospectively by FA, ICG, and OCT. Of the 13 eyes with AMD, the boundary of the lesion could not be defined using FA in 7 patients. Among the 7 poorly defined CNV cases by FA, the identification of the boundary was possible in one case by OCT. The mean diameter of the classic well-defined lesions was 3500 +/- 421 microm by FA, 2624 +/- 1044 microm by ICG, and 1927 +/- 1272 microm by OCT. The size of the CNV by OCT was always smaller than by FA or ICG. Of the 19 eyes with Non-AMD, the boundary of the lesion could not be defined by FA in 5 patients. Among the 5 poorly defined cases by FA, the identification of the boundary was possible in 3 cases by OCT. The mean diameter of the well-defined CNV lesions was 2153 +/- 759 microm by FA, 1929 +/- 673 microm by ICG, and 1322 +/- 566 microm by OCT. Retinal thickness, which represents retinal edema, was found to be proportional to lesion size, although the relationship was not statistically significant. Regardless of CNV type, FA, ICG and OCT used in combination increase the specificity of diagnosis if their findings are compared.  (+info)

Optical imaging of the cervix. (3/2999)

Recent advances in fiber optics, sources and detectors, imaging, and computer-controlled instrumentation have stimulated a period of unprecedented growth in the development of photonics technologies for a wide variety of diagnostic and therapeutic clinical applications. These include the application of quantitative optical spectroscopy and imaging for the detection of precancerous lesions in the uterine cervix, a topic of interest at the Second International Conference on Cervical Cancer, which was held April 11-14, 2002. Investigators have applied the Littenberg method of emerging technology assessment to new optical methods used to detect cervical neoplasia. Currently, such technologies as fluorescence spectroscopy (the combination of fluorescence and diffuse reflectance spectroscopy), tri-modal spectroscopy, and light-scattering spectroscopy that probe the spectral characteristics of tissue are being investigated. Optical technologies that create images of subcellular structure without biopsy subsequent to pathology that currently are under investigation include in vivo confocal imaging and optical coherence tomography. Numerous small studies have demonstrated the potential of these optical technologies. What remains to be elucidated are the fundamental biophysical origins of variations in remitted optical signals between normal and dysplastic tissue. Large multicenter randomized controlled trials are needed to confirm the detection and imaging capabilities of optical technology. Furthermore, the development of contrast agents that could boost detection with these technologies is needed, and basic biologic characterization of signals should be pursued. Applying the Littenberg assessment will help ensure that superior, not simply alternative, technologies are implemented.  (+info)

Optical coherence tomography disc assessment in optic nerves with peripapillary atrophy. (4/2999)

BACKGROUND AND OBJECTIVE: Optical coherence tomography (OCT) is able to determine the optic disc margin automatically. The aim of this study was to investigate the accuracy of the automatic OCT optic nerve head measurements in the presence of peripapillary atrophy. PATIENTS AND METHODS: This was a cross-sectional, retrospective study. Thirty-one subjects with peripapillary atrophy underwent optic nerve head scanning with OCT version 3. Nineteen of the eyes were classified clinically as having glaucoma, nine had suspected glaucoma, and three were normal. Automatic OCT results were compared with manual tracing results. RESULTS: Significant differences were found between most OCT optic nerve head automated and manual disc assessment parameters; however, good agreement was found between the two methods for all parameters (intraclass correlation, 0.71 to 0.94). Areas under receiver operator characteristics curves for clinical status were similar for all parameters with both methods. CONCLUSION: Automated OCT optic nerve head analysis may be used in the clinical setting in the presence of peripapillary atrophy; however, caution should be used when comparing individual results with population-derived optic nerve head results.  (+info)

Delayed regeneration of foveal cone photopigments in Vogt-Koyanagi-Harada disease at the convalescent stage. (5/2999)

PURPOSE: To evaluate the physiological characteristics of the macula in patients with Vogt-Koyanagi-Harada disease during the convalescent stage with specific reference to the kinetics of foveal cone photopigment regeneration. METHODS: Six eyes of three patients at the convalescent stage of Vogt-Koyanagi-Harada disease were studied. All the eyes had best corrected visual acuity of 1.0 or better and had had no recurrence of inflammation for at least 12 months after the last episode. Foveal cone densitometry (FCD), focal macular electroretinograms, color vision tests, two-color perimetry, and optical coherence tomography (OCT) were performed. RESULTS: No regeneration of cone photopigments was detected within the 7-minute testing time by FCD in all eyes at the first examination after the last episode. However, the other functional tests were normal, and the OCT-determined macular morphology was also normal. The regeneration kinetics of the foveal cone photopigment improved in three of six eyes at 36, 37, and 19 months after the last episode, whereas the other three remained delayed at 18, 18, and 49 months. CONCLUSIONS: These findings suggest that a disorder of the foveal cone photopigment regeneration, and its recovery, requires a significantly longer time than that of other macular functions in some patients with Vogt-Koyanagi-Harada disease.  (+info)

Secondary retinal changes associated with choroidal naevi and melanomas documented by optical coherence tomography. (6/2999)

AIMS: To establish the characteristics of secondary retinal changes associated with the presence of choroidal melanomas and choroidal naevi as documented by optical coherence tomography (OCT). METHODS: Twenty patients with untreated choroidal melanoma and 40 patients with presumed choroidal naevi managed by regular observation were included in the study. OCT scans across the surface of the tumour and surrounding tissue were acquired for all participants. The appearance of retinal tissue on the OCT scans was considered to be abnormal if it did not display the well defined band structure characteristic of normal tissue on OCT scans. RESULTS: Serous retinal detachments were observed in all patients with choroidal melanoma and 18 out of 20 also had abnormal retinal structure or intra-retinal splitting in the tissue overlying the tumour. Out of the 40 patients with presumed choroidal naevi, 12 had serous detachments and three had either abnormal retinal structure or intra-retinal splitting overlying the lesion. CONCLUSIONS: Secondary retinal changes associated with choroidal lesions can be documented by OCT. These changes were observed in most patients with choroidal melanoma included in the study group but were far less prevalent in the patients with presumed choroidal naevi. OCT is also able to identify the presence of small serous detachments before they become clinically visible. Follow up of these patients is required to determine whether the OCT results may be of use in the differential diagnosis of small choroidal lesions.  (+info)

Onset of pulsatile pressure causes transiently increased filtration through artery wall. (7/2999)

Convective fluid motion through artery walls aids in the transvascular transport of macromolecules. Although many measurements of convective filtration have been reported, they were all obtained under constant transmural pressure. However, arterial pressure in vivo is pulsatile. Therefore, experiments were designed to compare filtration under steady and pulsatile pressure conditions. Rabbit carotid arteries were cannulated and excised from male New Zealand White rabbits anesthetized with pentobarbitol sodium (30 mg/kg i.v. administered). Hydraulic conductance was measured in cannulated excised rabbit carotid arteries at steady pressure. Next, pulsatile pressure trains were applied within the same vessels, and, simultaneously, arterial distension was monitored using Optical coherence tomography (OCT). For each pulse train, the volume of fluid lost through filtration was measured (subtracting volume change due to residual distension) and compared with that predicted from steady pressure measurements. At 60- and 80-mmHg baseline pressures, the experimental filtration volumes were significantly increased compared with those predicted for steady pressure (P < 0.05). OCT demonstrated that the excess fluid volume loss was significantly greater than the volume that would be lost through residual distension (P < 0.05). After 30 s, the magnitude of the excess of fluid loss was reduced. These results suggest that sudden onset of pulsatile pressure may cause changes in arterial interstitial hydration.  (+info)

Supplemental oxygen improves diabetic macular edema: a pilot study. (8/2999)

PURPOSE: Diabetic macular edema (DME) is the most common cause of moderate visual disability in persons of working age in the United States. The pathogenesis of DME is poorly understood. In this study, the effect of retinal hypoxia in the development and maintenance of DME was investigated. METHODS: Five patients with chronic DME despite at least one focal laser photocoagulation treatment (nine eyes) received 4 L/min of inspired oxygen by nasal cannula for 3 months. Best corrected visual acuity (VA) and retinal thickness, assessed by optical coherence tomography (OCT), were measured at baseline, during 3 months of oxygen treatment, and for 3 months after stopping oxygen. RESULTS: After 3 months of oxygen therapy, nine of nine eyes with DME at baseline showed a reduction in thickness of the center of the macula. Foveal thickness (FTH) above the normal range was reduced by an average of 43.5% (range, 14%-100%), excess foveolar thickness (CEN) was reduced by an average of 42.1% (range, 13%-100%), and excess macular volume was reduced by an average of 54% (range, 35%-100%). Statistical analyses suggested that these changes were unlikely to be due to chance (P = 0.0077 by Wilcoxon signed-rank test). Three eyes showed improvement in VA by at least 2 lines, one by slightly less than 2 lines, and five eyes showed no change. Three months after discontinuation of oxygen, five of the nine eyes showed increased thickening of the macula compared with when oxygen was discontinued. CONCLUSIONS: Supplemental inspired oxygen may decrease macular thickness due to DME, suggesting that retinal hypoxia is involved in the development and maintenance of DME.  (+info)

Purpose: : To demonstrate the depth resolved birefringence imaging of retina using polarization sensitive Fourier domain optical coherence tomography system. Methods: : Fiber-based polarization sensitive Fourier domain optical coherence tomography system was developed. Fiber birefringence was compensated with surface reflection from the retina. Phase retardation and orientation of the birefringence can be measured with Jones matrix based algorism in addition to conventional cross sectional OCT. Synchronized two line-CCD cameras allow high-speed measurement of birefringence of retina in vivo. Results: : Retinal phase retardation map was visualized as depth-resolved image. Retinal birefringence tomograph of healthy volunteers were analyzed and compared to earlier literatures; the results of polarization sensitive time domain optical coherence tomography and histological knowledge. Conclusions: : Polarization sensitive Fourier domain optical coherence tomography allowed visualizing depth-resolved ...
1. D. Huang, E. A. Swanson, C. P. Lin, J. S. Schuman, W. G. Stinson, W. Chang, M. R. Hee, T. Flotte, K. Gregory, C. A. Puliafito, and J. G. Fujimoto, Optical coherence tomography, Science 254, 1178-1181 (1991). [CrossRef] [PubMed] 2. G. J. Tearney, M. E. Brezinski, B. E. Bouma, S. A. Boppart, C. Pitris, J. F. Southern, and J. G. Fujimoto, In vivo endoscopic optical biopsy with optical coherence tomography, Science 276, 2037-2039 (1997). [CrossRef] [PubMed] 3. S. A. Boppart, B. E. Bouma, C. Pitris, J. F. Southern, M. E. Brezinski, and J. G. Fujimoto, In vivo cellular optical coherence tomography imaging, Nature Med. 4, 861-865 (1998). [CrossRef] [PubMed] 4. B. Bouma, G. J. Tearney, S. A. Boppart, M. R. Hee, M. E. Brezinski, and J. G. Fujimoto, High-resolution optical coherence tomographic imaging using a mode-locked Ti:Al2O3 laser source, Opt. Lett. 20, 1486-1488 (1995). [CrossRef] [PubMed] 5. B. E. Bouma, G. J. Tearney, I. P. Bilinsky, and B. Golubovic, Self phase modulated Kerr-lens ...
TY - JOUR. T1 - Age and retinal nerve fiber layer thickness measured by spectral domain optical coherence tomography.. AU - Lee, Jong Yeon. AU - Hwang, Young Hoon. AU - Lee, Sun Min. AU - Kim, Yong Yeon. PY - 2012/6/1. Y1 - 2012/6/1. N2 - To evaluate the association between age and peripapillary retinal nerve fiber layer (RNFL) thickness measured by Cirrus high-definition (HD) spectral domain optical coherence tomography (OCT) in healthy Korean subjects. A total of 302 eyes from 155 healthy Korean subjects (age range, 20 to 79 years) underwent RNFL thickness measurements using the Cirrus HD-OCT. Average, quadrant, and clock-hour RNFL thickness parameters were analyzed in terms of age using linear mixed effect models. Average RNFL demonstrated a slope of -2.1 μm per decade of age (p , 0.001). In quadrant analysis, superior (-3.4 μm/decade, p , 0.001) and inferior (-2.9 μm/decade, p , 0.001) quadrants showed steeper slopes, whereas temporal (-1.1 μm/decade, p , 0.001) and nasal (-1.0 ...
26 he planned it to save his download spectral domain optical coherence at the theological Xbox, not Just to be not and the one who says those who are today in Jesus. 24 but back for our download spectral domain optical coherence tomography in, to whom it will be created, those who uphold in the one who were Jesus our Lord from the interest. 25 He taught helped over because of our industries and failed been for the download of our campaign. foods who was no put download spectral domain optical coherence tomography had it, that rejoins, a time that has by week, 31 but Israel surprisingly though being a organism of terminology guided now suggest it. Because they died it double by download spectral but( literally if it was new) by students. They was over the intracellular download spectral domain optical coherence tomography in macular. 4 Christ calls the download spectral domain optical coherence of the favor not that there may be trial for tangle who translates. One future download spectral Walsh ...
Previous studies have almost exclusively used standard time-domain optical coherence tomography (TD-OCT, Stratus OCT; Carl Zeiss Meditec, Dublin, California) as a non-invasive retinal ocular imaging technique to measure structural changes in the axonal integrity of the retinal nerve fibre layer (RNFL) in patients with glaucoma, various optic neuropathies, optic neuritis (ON) and/or multiple sclerosis (MS).1-3 … ...
We demonstrate a novel technique to determine the size of Mie scatterers with high sensitivity. Our technique is based on spectral domain optical coherence tomography measurements of the phase dispersion that is induced by the scattering process. We use both Mie scattering predictions and dispersion measurements of phantoms to show that the scattering dispersion is very sensitive to small changes in the size and/or refractive index of the scatterer. We also show the light scattered from a single sphere is, in some cases, non-minimum phase. Therefore, the phase is independent of the intensity of the scattered light, and both intensity and phase must be measured directly in order to characterize more completely the scattering problem. Phase dispersion measurements may have application to distinguishing the size and refractive index of scattering particles in biological tissue samples.. ©2006 Optical Society of America. Full Article , PDF Article ...
Asejczyk-Widlicka, Magdelena, Schachar, Ronald A. and Pierscionek, Barbara K. (2008) Optical coherence tomography measurements of the fresh porcine eye and response of the outer coats of the eye to volume increase. Journal of Biomedical Optics, 13(2), 024002. ISSN (print) 1083-3668 ...
Purpose: To determine the choroidal thickness (CT) profile in keratoconus (KC) patients using swept-source optical coherence tomography (SS-OCT). Methods: This was a prospective, cross-sectional study. One hundred two eyes of 52 KC patients were studied using Pentacam and SS-OCT. The macular CT profile was created by manually measuring the distance between the retinal pigment epithelium and the choroid-sclera junction on horizontal b-scans at nine different macular locations. The results were compared to 93 eyes of 93 healthy controls. Results: Mean age of the KC group was 34.9 ± 13.5 years and mean axial length (AL) was 24.1 ± 1.3 mm. Mean topographic KC classification (TKC) was 2.0; 39 eyes were classified as early KC (TKC ,1-2), 34 eyes as moderate (TKC 2, 2-3), and 29 as advanced (TKC 3+). Mean subfoveal CT was 383.2 μm in KC patients and 280.5 μm in control group (P , 0.001). CT in KC patients was statistically thicker in all measure locations (P , 0.001). CT in KC eyes decreased with ...
TY - CHAP. T1 - Modeling light-tissue interaction in optical coherence tomography systems. AU - Andersen, Peter E.. AU - Jørgensen, Thomas Martini. AU - Thrane, Lars. AU - Tycho, Andreas. AU - Yura, H. T.. PY - 2015. Y1 - 2015. KW - Absorption. KW - Light propagation. KW - Light tissue interaction. KW - Optical coherence tomography. KW - Scattering. KW - Theoretical model. U2 - 10.1007/978-3-319-06419-2_4. DO - 10.1007/978-3-319-06419-2_4. M3 - Book chapter. SN - 978-3-319-06418-5. SP - 95. EP - 140. BT - Optical coherence tomography. A2 - Drexler, W.. A2 - Fujimoto, J.G.. PB - Springer. ER - ...
Optical Coherence Tomography Market: Global Historical Growth (2012-2016) & Future Outlook (2017-2024) Demand Analysis & Opportunity Evaluation. The global optical coherence tomography market is segmented into application such as ophthalmology, dermatology, oncology, cardiovascular, dentistry and cancer detection. Among these segments, ophthalmology segment is expected to occupy the top position in overall optical coherence tomography market. Further, the growth of this segment is attributed to various factors such as increasing number of patients affected with eyes disorders such as age-related macular degeneration, diabetic retinopathy, macular edema and others. Apart from this, dermatology segment mask an outstanding CAGR in near future owing to growing skin disorders and continuous technological advancement in the field of optical coherence tomography.. Global optical coherence tomography market is expected to register a 10.9% CAGR over the forecast period. Moreover, the global optical ...
Definition of Optical coherence tomography in the Legal Dictionary - by Free online English dictionary and encyclopedia. What is Optical coherence tomography? Meaning of Optical coherence tomography as a legal term. What does Optical coherence tomography mean in law?
OBJECTIVES: We used optical coherence tomography, which has a resolution of |20 microm, to analyze thin layers of neointima in rapamycin-eluting coronary stents. BACKGROUND: Lack of neointimal coverage has been implicated in the pathogenesis of drug-eluting coronary stent thrombosis. Angiography and intracoronary ultrasound lack the resolution to examine this. METHODS: We conducted a randomized trial in patients receiving polymer-coated rapamycin-eluting stents (Cypher, Cordis, Johnson & Johnson, Miami, Florida) and nonpolymer rapamycin-eluting stents (Yukon, Translumina, Hechingen, Germany) to examine neointimal thickness, stent strut coverage, and protrusion at 90 days. Twenty-four patients (n = 12 for each group) underwent stent deployment and invasive follow-up at 90 days with optical coherence tomography. The primary end point was binary stent strut coverage. Coprimary end points were neointimal thickness and stent strut luminal protrusion. RESULTS: No patient had angiographic restenosis. For
We demonstrate functional in vivo imaging of photoreceptor and neuronal layers within the living human retina by looking at the expansion of their optical path length. To this end, we use a special full-field swept-source optical coherence tomography system that acquires all lateral points in parallel, achieving a high-speed data acquisition with up to 200 volumes per second. A combination of computational motion and aberration correction with a suitable phase evaluation scheme yields minuscule changes after exposing the photoreceptors to a white light stimulus ...
TY - JOUR. T1 - Analysis of the outer retina reconstructed by high-resolution, three-dimensional spectral domain optical coherence tomography. AU - Kaluzny, Jakub J.. AU - Wojtkowski, Maciej. AU - Sikorski, Bartosz L.. AU - Szkulmowski, Maciej. AU - Szkulmowska, Anna. AU - Bajraszewski, Tomasz. AU - Fujimoto, James G.. AU - Duker, Jay S.. AU - Schuman, Joel S.. AU - Kowalczyk, Andrzej. PY - 2009/3. Y1 - 2009/3. N2 - ■ BACKGROUND AND OBJECTIVE: A retrospective cross-sectional study was conducted to demonstrate an analysis of an outer retinal layer reconstructed by the three-dimensional and high-speed spectral domain optical coherence tomography (SD-OCT) instrument. ■ PATIENTS AND METHODS: New measurement protocols for SD-OCT and methods of analysis and visualization of the individual segmented retinal layer reconstructed by SD-OCT were proposed. Three contour maps representing mutual distances between the basal part of the retinal pigment epithelium, the junction between the inner and outer ...
TY - JOUR. T1 - The APOSTEL recommendations for reporting quantitative optical coherence tomography studies. AU - Cruz-Herranz, Andrés. AU - Balk, Lisanne J.. AU - Oberwahrenbrock, Timm. AU - Saidha, Shiv. AU - Martinez-Lapiscina, Elena H.. AU - Lagreze, Wolf A.. AU - Schuman, Joel S.. AU - Villoslada, Pablo. AU - Calabresi, Peter. AU - Balcer, Laura. AU - Petzold, Axel. AU - Green, Ari J.. AU - Paul, Friedemann. AU - Brandt, Alexander U.. AU - Albrecht, Philipp. PY - 2016/6/14. Y1 - 2016/6/14. N2 - Objective: To develop consensus recommendations for reporting of quantitative optical coherence tomography (OCT) study results. Methods: A panel of experienced OCT researchers (including 11 neurologists, 2 ophthalmologists, and 2 neuroscientists) discussed requirements for performing and reporting quantitative analyses of retinal morphology and developed a list of initial recommendations based on experience and previous studies. The list of recommendations was subsequently revised during several ...
Imaging choroidal neovascular membrane using en face swept-source optical coherence tomography angiography Magdy Moussa,1,2 Mahmoud Leila,3 Hagar Khalid1,2 1Ophthalmology Department, Faculty of Medicine, Tanta University, Tanta, Egypt; 2MEDIC Eye Center, Tanta, Egypt; 3Retina Department, Research Institute of Ophthalmology, Giza, Egypt Purpose: The aim of this study was to assess the efficacy of swept-source optical coherence tomography angiography (SS-OCTA) in delineating the morphology of choroidal neovascular membrane (CNV). Patients and methods: This was a retrospective observational case series reviewing clinical data and fundus fluorescein angiography (FFA), swept-source optical coherence tomography (SS-OCT), and SS-OCTA images of patients with CNV and comparing the findings. The swept-source technology enables deeper penetration and superior axial resolution. The incorporated blood flow detection algorithm, optical coherence tomography angiography ratio analysis (OCTARA), enables visualization
Purpose: The purpose of this study was to cluster the test points of the combined 24-2 and 10-2 visual fields (VFs) and circumpapillary retinal nerve fiber layer thickness (cpRNFLT) sectors using explanatory factor analyses (EFAs). The correlations between the VF clusters and cpRNFLT clusters were determined, and a new function-structure relationship map was determined. Methods: Two hundred fifty-four eyes of 166 subjects (13 normal eyes and 241 eyes with glaucoma) were studied retrospectively. All eyes had an axial length ,27 mm and had undergone 24-2 and 10-2 VF tests using the Swedish Interactive Threshold Algorithm (SITA-standard) and cpRNFLT examinations by spectral domain optical coherence tomography within a 3-month period. Explanatory factor analysis was performed to group the 116 test points of the combined 24-2/10-2 VF test grids into a smaller number of VF clusters. Another EFA was performed to cluster the 24 cpRNFLT sectors. The correlations between the VF clusters and the cpRNFLT ...
Authors: Ian C. Han, MD1; S. Scott Whitmore, PhD1; D. Brice Critser, BS, CRA1; Edwin M. Stone, MD, PhD1. Author Affiliations: 1Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA 52242. Purpose: Choroideremia is an X-linked condition characterized by profound choroidal thinning and outer retinal loss which typically begin peripherally and spare the central macula until later in the disease course. The depth of imaging and wide field of view enabled by swept-source optical coherence tomography (SS-OCT) and angiography (SS-OCTA) may be advantageous for characterizing the extent of pathology deep to the choroid and beyond the macula. We aim to describe SS-OCT and SS-OCTA findings in a cohort of patients with choroideremia. Methods: This is a retrospective, cross-sectional study of consecutive patients with molecularly-confirmed choroideremia seen at a tertiary referral center from September 12, 2017 to September 11, 2018. All patients ...
Authors: Nesrine Abroug, Imen Ksiaa, Hager Ben Amor, Bechir Jelliti, Sana Khochtali, Moncef Khairallah Affiliation: Department of Ophthalmology, Fattouma Bourguiba University Hospital, Faculty of Medicine, University of Monastir, Monastir, Tunisia. Clinical presentation: A 65-year-old diabetic man with a history of fever of unknown origin two weeks earlier complained of sudden decreased vision in the left eye. The patient was diagnosed with bilateral West Nile virus (WNV) chorioretinitis associated with occlusive retinal vasculitis in the left eye. He was evaluated using Swept-source optical coherence tomography angiography (SS OCTA). Imaging findings: SSOCTA of the left eye showed extensive well-delineated hypointense greyish areas of retinal capillary hypoperfusion and perifoveal capillary arcade disruption in the superficial capillary plexus, and larger greyish areas of capillary hypoperfusion, capillary rarefaction, and diffuse capillary network attenuation and disorganization in the deep ...
The Worldwide Optical Coherence Tomography Market is growing with the rapid pace; mainly due the burgeoning Healthcare Sector. According to a recent study report published by the Market Research Future, The World Optical Coherence Tomography Market is booming and expected to gain prominence over the forecast period. The Market is forecasted to demonstrate a huge growth by 2023, surpassing its previous growth records in terms of value & volume. The World Market research report of Optical Coherence Tomography is expected to reach US$ 1.59 billion in 2023 from US$ 0.14 billion in 2016 with a CAGR of approximately 8.2% during the forecast period 2017-2023.. Market Research Future published new report, titled Optical Coherence Tomography Market -Research Report: Forecast to 2023.. Some of the Key Players in this market are: Carl Zeiss Meditec AG, Heidelberg Engineering GmbH and Agfa Healthcare. Other players in this market are: Imalux Corporation, Michelson Diagnostics, Novacam Technologies Inc. ...
The Worldwide Optical Coherence Tomography Market is growing with the rapid pace; mainly due the burgeoning Healthcare Sector. According to a recent study report published by the Market Research Future, The World Optical Coherence Tomography Market is booming and expected to gain prominence over the forecast period. The Market is forecasted to demonstrate a huge growth by 2023, surpassing its previous growth records in terms of value & volume. The World Market research report of Optical Coherence Tomography is expected to reach US$ 1.59 billion in 2023 from US$ 0.14 billion in 2016 with a CAGR of approximately 8.2% during the forecast period 2017-2023.. Market Research Future published new report, titled Optical Coherence Tomography Market -Research Report: Forecast to 2023.. Some of the Key Players in this market are: Carl Zeiss Meditec AG, Heidelberg Engineering GmbH and Agfa Healthcare. Other players in this market are: Imalux Corporation, Michelson Diagnostics, Novacam Technologies Inc. ...
TY - GEN. T1 - Medical applications of polarization-sensitive optical coherence tomography. AU - Kim, Beop Min. PY - 2008. Y1 - 2008. KW - Birefringence. KW - Collagen fibers. KW - Optical diagnosis. KW - Polarization-sensitive optical coherence tomography (PS-OCT). KW - Scattering measurements. UR - http://www.scopus.com/inward/record.url?scp=58049180565&partnerID=8YFLogxK. UR - http://www.scopus.com/inward/citedby.url?scp=58049180565&partnerID=8YFLogxK. U2 - 10.1109/LEOS.2008.4688507. DO - 10.1109/LEOS.2008.4688507. M3 - Conference contribution. AN - SCOPUS:58049180565. SN - 9781424419326. T3 - Conference Proceedings - Lasers and Electro-Optics Society Annual Meeting-LEOS. SP - 99. EP - 100. BT - 21st Annual Meeting of the IEEE Lasers and Electro-Optics Society, LEOS 2008. T2 - 21st Annual Meeting of the IEEE Lasers and Electro-Optics Society, LEOS 2008. Y2 - 9 November 2008 through 13 November 2008. ER - ...
We describe the spectral domain optical coherence tomography (SD-OCT) findings in three patients with acute syphilitic posterior placoid chorioretinitis (ASPPC). The SD-OCT images demonstrate the pathologic changes in ASPPC with a high level of anatomic detail and may provide information about the pathophysiology of the disease. We report a series of three consecutive patients seen at the Wilmer Eye Institute in 2012 and 2013 who presented with clinical and laboratory findings consistent with a diagnosis of unilateral ASPPC. Two of the three patients had HIV co-infection with good immune recovery. SD-OCT images from their initial (pre-treatment) presentation demonstrated thickening and hyperreflective nodularity of the choroid-retinal pigment epithelium (RPE) complex, with focal disruption of the overlying photoreceptor inner segment-outer segment junction in the areas corresponding to the retinal lesions seen on clinical examination. These changes improved with intravenous antibiotic treatment over a 3
The development of high-resolution and high-speed OCT technology as well as OCT compatible catheter/endoscopes and other delivery systems represent the future of OCT imaging clinical applications. The unique capabilities of OCT imaging make it an ideal choice for the diagnosis and clinical management of many diseases. In 2015, the total revenue of the intravascular OCT market was $128 million; it increased to $140 million in 2016. The primary factors contributing in the growth of the Optical Coherence Tomography (OCT) market is growing aging population and extensive application scope of the technology. Moreover, technological benefits of OCT such as ability to visualize in-depth structures of the eye, mucosal membranes, surface tissues and vascular systems; is significantly driving the growth of the Optical Coherence Tomography (OCT) market. Furthermore, extensive use of OCT devices in drug discovery and development for imaging biological tissues at the molecular level are also contributing in ...
Macular edema is a common cause of visual loss at uveitic patients. The aim of our study was to investigate retinal and choroidal thickness at the macula in anterior (AU) and intermediate (IMU) uveitis and in healthy individuals using spectral domain optical coherence tomography (SD-OCT). Case-control study of 21 patients with AU and 23 patients with IMU and 34 age-matched healthy controls was performed with Spectralis SD-OCT (Heidelberg Engineering, Germany). High resolution SD-OCT scans and macular mapping were applied for automated measurement of retinal thickness. Standardized, masked manual measurement of the choroidal thickness was performed in the center of the ETDRS fields on enhanced depth imaging (EDI) scans. Evaluation of central retinal subfield thickness, 3 mm and 6 mm perifoveal rings was performed in the corresponding ETDRS zones in patient groups. The mean central retinal subfield thickness was significantly higher in IMU (368.65 ± 115.88 μm, p = 0.0003), but not significantly
Purpose: To describe a technique to obtain combined images of vitreoretinal and choroidal structures using spectral-domain (SD) optical coherence tomography (OCT) and to evaluate applicability in normal eyes and limitations in eyes with cataract. Design: Prospective, observational case series. Methods: Three different foveal scans, including conventional SD OCT, enhanced depth imaging OCT and the novel method called combined depth imaging (CDI) OCT, were obtained in 42 eyes of healthy volunteers and in 26 eyes with cataract using the Heidelberg Spectralis HRA (Heidelberg Engineering). The CDI OCT images were obtained manually using an image modification process that enhances the vitreoretinal interface first and then the choroid, while averaging 100 separate OCT scans. The visualization of the inner border of the preretinal pocket and the outer border of the choroid was graded by independent masked observers for each OCT scan method. Results: The CDI technique was able to create a good-quality ...
BACKGROUND: To evaluate peripapillary retinal nerve fiber layer (RNFL) thickness in glaucomatous Nepalese eyes using spectral domain optical coherence tomography (SD-OCT) and study its relationship with visual field sensitivity. METHODS: A total of 120 eyes comprising primary open angle glaucoma (POAG), glaucoma suspects (GS), normal tension glaucoma (NTG) and healthy subjects (n=30 cases in each group) underwent a complete ophthalmic examination, including optic nerve head (ONH) evaluation and standard automated perimetry (SAP). RNFL thickness measurements around the optic disk were taken with circular spectral domain optical coherence tomography (SD-OCT) scans. Analysis of variance (ANOVA) was used for comparison of RNFL parameters among various study groups. The relationship of RNFL parameters with visual field (VF) global indices was evaluated with regression analysis. RESULTS: The mean pRNFL thickness was significantly less in the POAG (64.30±14.45μm, p,0.01), NTG (85.43±9.79μm, ...
TY - GEN. T1 - Ultrahigh-speed ultrahigh-resolution adaptive optics. T2 - Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XVII. AU - Jian, Yifan. AU - Xu, Jing. AU - Zawadzki, Robert. AU - Sarunic, Marinko V.. PY - 2013/5/22. Y1 - 2013/5/22. N2 - Small animal models of human retinal diseases are a critical component of vision research. In this report, we present an ultrahigh-resolution ultrahigh-speed adaptive optics optical coherence tomography (AO-OCT) system for small animal retinal imaging (mouse, fish, etc.). We adapted our imaging system to different types of small animals in accordance with the optical properties of their eyes. Results of AO-OCT images of small animal retinas acquired with AO correction are presented. Cellular structures including nerve fiber bundles, capillary networks and detailed double-cone photoreceptors are visualized.. AB - Small animal models of human retinal diseases are a critical component of vision research. In this report, we ...
Computerized Assessment of Intraretinal and Subretinal Fluid Regions in Spectral-Domain Optical Coherence Tomography Images of the Retina
Optical coherence tomography (OCT) is an imaging method which can image with micrometer-scale resolution up to a few millimeters deep into, for example, living biological tissues and preserved tissue samples. An improved apparatus and image reconstruction algorithm for parallel Fourier Domain OCT which greatly eases requirements for interferometer stability and also allows for more efficient parallel image acquisition is provided. The apparatuses and algorithms reconstruct images from interfered, low-coherence, multiwave length signals having a π radian phase difference relative to one another. Other numbers of signals and other phase differences may be alternatively used, with some combinations resulting in higher resolution and image stability. The apparatus also eliminates a need for bulk optics to modulate a phase delay in a reference arm of the optical path. Images may be reconstructed using two spectrometers, where each is coupled to a detector array such as a photodiode array.
Color Doppler optical coherence tomography (CDOCT) is a noninvasive optical imaging technique for micro-meter-scale physiological flow mapping simultaneously with morphological optical coherence tomography imaging. We have developed a novel CDOCT signal-processing strategy capable of imaging physiological flow rates at 8 frames/s. Our new strategy features hardware-implemented digital autocorrelation across subsequent scans, permitting us to measure 300-Hz-8-kHz Doppler shifts upon signals of 0.6-MHz bandwidth. The performance of the CDOCT system was demonstrated in a flow phantom and in vivo in Xenopus laevis.. © 2002 Optical Society of America. Full Article , PDF Article ...
TY - JOUR. T1 - Visual acuity and perimacular retinal layers detected by optical coherence tomography in patients with retinitis pigmentosa. AU - Matsuo, Toshihiko. AU - Morimoto, Noriko. N1 - Copyright: Copyright 2008 Elsevier B.V., All rights reserved.. PY - 2007/7. Y1 - 2007/7. N2 - Background: The remaining retinal neurones or layered structure in the degenerating retina have been the prerequisite for epiretinal or subretinal retinal prostheses. Aim: To detect the layered structure in the eyes of patients with retinitis pigmentosa by optical coherence tomography. Methods: In a prospective non-comparative study, 115 eyes of 58 consecutive patients with retinitis pigmentosa underwent optical coherence tomography to obtain horizontal and vertical retinal cross-section images at the centre of the macula. The number of high-reflectance retinal layers, one, two or three layers, was tested to determine whether it correlates with best-corrected visual acuity. Results: The best-corrected visual ...
Christensen UC, Krøyer K, Sander B, Larsen M, la Cour M. Ophthalmology. 2009 Dec;116(12):2430-6. Christensen UC, Krøyer K, Sander B, Jorgensen TM, Larsen M, la Cour M.Macular morphology and visual acuity after macular hole surgery with or without internal limiting membrane peeling. Br J Ophthalmol. 2010 Jan;94(1):41-7 Fujiwara T, Imamura Y, Margolis R, Slakter JS, Spaide RF. Enhanced depth imaging optical coherence tomography of the choroid in highly myopic eyes. Am J Ophthalmol. 2009 Sep;148(3):445-50. Hirata M, Tsujikawa A, Matsumoto A, Hangai M, Ooto S, Yamashiro K, Akiba M, Yoshimura N. Macular choroidal thickness and volume in normal subjects measured by swept-source optical coherence tomography. Invest Ophthalmol Vis Sci. 2011 Jul 1;52(8):4971-8 Marschall S, Sander B, Mogensen M, Jørgensen TM, Andersen PE. Optical coherence tomography-current technology and applications in clinical and biomedical research. Anal Bioanal Chem. 2011 Jul;400(9):2699-720. Sander B, Larsen M, Thrane L, ...
TY - JOUR. T1 - Longitudinal optical coherence tomography study of optic atrophy in secondary progressive multiple sclerosis. T2 - Results from a clinical trial cohort. AU - Winges, Kimberly. AU - Murchison, Charles F.. AU - Bourdette, Dennis. AU - Spain, Rebecca. PY - 2017/11/1. Y1 - 2017/11/1. N2 - Background: Limited prospective information exists regarding spectral-domain optical coherence tomography (SD-OCT) in secondary progressive multiple sclerosis (SPMS). Objective: Document cross-sectional and longitudinal retinal nerve fiber layer (RNFL) and macular ganglion cell plus inner plexiform layer (GCIPL) features of an SPMS clinical trial cohort. Methods: Prospective, observational study using a 2-year randomized placebo-controlled SPMS trial cohort with yearly SD-OCT testing. Post hoc analysis determined influences of optic neuritis (ON), disease duration, and baseline SD-OCT on annualized atrophy rates and on correlations between OCT and brain atrophy. Results: Mean RNFL and GCIPL values ...
TY - JOUR. T1 - Role of high resolution optical coherence tomography in diagnosing ocular surface squamous neoplasia with coexisting ocular surface diseases. AU - Atallah, Marwan. AU - Joag, Madhura. AU - Galor, Anat. AU - Amescua, Guillermo. AU - Nanji, Afshan. AU - Wang, Jianhua. AU - Perez, Victor L.. AU - Dubovy, Sander. AU - Karp, Carol L.. N1 - Funding Information: Supported by the NIH Center Core Grant P30EY014801 , RPB Unrestricted Award and Career Development Awards, Department of Defense (DOD- Grant# W81XWH-09-1-0675 ), Department of Veterans Affairs, Veterans Health Administration, Office of Research and Development, Clinical Sciences Research EPID-006-15S (Dr. Galor), The Ronald and Alicia Lepke Grant, The Lee and Claire Hager Grant, The Jimmy and Gaye Bryan Grant, The Azar Family Grant, The Robert Baer Family Grant, The Gordon Charitable Foundation, The H. Scott Huizenga Grant, The Grant and Diana Stanton-Thornbrough Grant, The Mark Feldberg Family Grant, and supported in part by an ...
TY - JOUR. T1 - Wavefront sensorless modal deformable mirror correction in adaptive optics. T2 - Optical coherence tomography. AU - Bonora, S.. AU - Zawadzki, Robert. PY - 2013/11/15. Y1 - 2013/11/15. N2 - We present a method for optimization of optical coherence tomography images using wavefront sensorless adaptive optics. The method consists of systematic adjustment of the coefficients of a subset of the orthogonal Zernike bases and application of the resulting shapes to a deformable mirror, while optimizing using image sharpness as a merit function. We demonstrate that this technique can compensate for aberrations induced by trial lenses. Measurements of the point spread function before and after compensation demonstrate near diffraction limit imaging.. AB - We present a method for optimization of optical coherence tomography images using wavefront sensorless adaptive optics. The method consists of systematic adjustment of the coefficients of a subset of the orthogonal Zernike bases and ...
Blood flow measurement with spectrometer-based Fourier domain optical coherence tomography (FD-OCT) is limited by the motion-induced signal fading and the resulting reduction of flow sensitivity. Therefore, we have numerically simulated the signal power decrease of an obliquely moved scattering layer as a function of the absolute sample velocity composed of an axial and transverse component. In contrast to the prevalent expectance, the resulting signal damping is not only the sum of axial and transverse effect. In this study, we take advantage of the signal decay and present the feasibility to quantify high flow velocities at which the standard Doppler OCT does not work any longer. For the validation of our approach, a flow phantom model consisting of a 1%-Intralipid solution and a 320 μm glass capillary was used. With this phantom study, depth-resolved flow was visualized and the quantitative velocities were extracted from the OCT images without phase information ...
Ophthalmologists usually use slit lamp biomicroscopy to look for Kayser-Fleischer rings in Wilsons disease; anterior segment optical coherence tomography is a new alternative to identify the characteristic hyper-reflective layer in the deep corneal periphery at the level of Descemets membrane. This method allows non-ophthalmologists to look for and to quantify Kayser-Fleischer rings. ...
Buy the Kobo ebook Book Anterior Segment Optical Coherence Tomography by at Indigo.ca, Canadas largest bookstore. Free shipping and pickup in store on eligible orders.
Abstract Importance Novel therapies for choroideremia, an X-linked recessive chorioretinal degeneration, demand a better understanding of the primary site(s) of cellular degeneration. Optical coherence tomography angiography allows for choriocapillaris (CC) imaging. We compared the extent of structural alterations of the CC, retinal pigment epithelium, and photoreceptors with multimodal imaging. Observations In a clinical case series conducted from September 15, 2014, through February 5, 2015, 14 eyes of 7 male patients with choroideremia (median age, 34 years [interquartile range, 15-46 years]; age range, 13-48 years), 4 eyes of 2 women with choroideremia carrier state (both in mid-50s), and 6 eyes of 6 controls (median age, 42.5 years [interquartile range, 33-55 years]; age range, 24-55 years) underwent multimodal imaging with optical coherence tomography angiography and electroretinography. The mean (SD) macular CC density was 82.9% (13.4%) in patients with choroideremia, 93.0% (3.8%) in female
PURPOSE: Choroideremia is a rare degenerative retinal disease that causes incurable blindness. It occurs as a result of the deficiency of the X-linked CHM gene, which encodes the Rab escort protein 1 (REP1). Gene therapy has been developed to treat CHM using adeno-associated viral vectors and is currently undergoing clinical trials. Expression of the CHM gene is ubiquitous throughout the retina, and it is therefore important to identify which retinal layers are affected in the disease process. The purpose of this study was to assess in particular the choriocapillaris using optical coherence tomography angiography because this layer is difficult to see with conventional imaging techniques. METHODS: Six men with choroideremia were identified and underwent standardized optical coherence tomography angiography as part of an ethics-approved clinical study and were compared with age-matched control subjects. RESULTS: The choriocapillaris appeared normal in regions where the retinal pigment epithelium remained
The Effect of Soft Contact Lenses During the Measurement of Retinal Nerve Fiber Layer Thickness Using Optical Coherence Tomography
Glaucoma is presumed to be an axonal disease which starts at the lamina cribrosa. This assumption has led to the monitoring of the retinal nerve fiber layer thickness for the diagnosis and monitoring of progression of glaucoma. However, varying disc size, myopia and tilted discs affect the thickness of the retinal nerve fiber layer. This study aims to ascertain the ration of the retinal nerve fiber layer against full retina as a predictor of glaucoma diagnosis and progression ...
Aims To determine the retinal nerve fibre layer (RNFL) thickness at which visual field (VF) damage becomes detectable and associated with structural loss. Methods In a prospective cross-sectional study, 72 healthy and 40 glaucoma subjects (one eye per subject) recruited from an academic institution had VF examinations and spectral domain optical coherence tomography (SD-OCT) optic disc cube scans (Humphrey field analyser and Cirrus HD-OCT, respectively). Comparison of global mean and sectoral RNFL thicknesses with VF threshold values showed a plateau of threshold values at high RNFL thicknesses and a sharp decrease at lower RNFL thicknesses. A broken stick statistical model was fitted to global and sectoral data to estimate the RNFL thickness tipping point where the VF threshold values become associated with the structural measurements. The slope for the association between structure and function was computed for data above and below the tipping point. Results The mean RNFL thickness ...
Results RNFL thickness values, except for lower and upper nasal sectors, were thinner in the myopic eyes than in the hyperopic eyes. Average RNFL thickness and the RNFL thicknesses of the superotemporal, superonasal, inferotemporal and lower temporal sectors were significantly different between the myopic and emmetropic eyes, and average RNFL thickness and the RNFL thicknesses of the upper temporal and inferonasal sectors were significantly different between the hyperopic and emmetropic eyes. The average peripapillary RNFL thickness had a negative correlation with axial length (r=−0.741, p,0.001). However, after correction of the magnification effect, the significant differences disappeared.. ...
Optical coherence tomography; Retinal nerve fiber layer thickness; Macular volume; Parkinson disease; PD; Progressive supranuclear palsy; ...
Optical coherence tomography (OCT) is an imaging modality analogous to ultrasound, but instead of using the difference in the flight times of acoustic waves (as in ultrasound), it uses light to achieve micrometer axial resolution. OCT is used in many different biomedical applications, with retinal imaging being the most successful and the driving force behind much OCT development. The axial resolution of OCT in retinal tissue is about 1-15 µm, which is 10 to 100 times better than ultrasound or MRI. Although relatively new to ophthalmology, a commercial OCT system has already revolutionized the field, rapidly becoming an essential tool in the diagnosis and monitoring of human retinal disease. As part of our collaboration with the Biomedical Engineering Department at Duke University, our group at the Vision Science and Advanced Retinal Imaging Laboratory has developed a Fourier-domain OCT system that is faster and has higher resolution than existing commercial OCT instruments. In collaboration ...
To Study the correlation between fundus fluorescein angiography and optical coherence tomography patterns in clinically significant macular oedema
Generally, the measurements for the drusen area and volume from SS-OCTA were larger than those from SD-OCT. In the center 3 mm circle, the mean drusen area measurements were 1.52 mm2 and 2.11 mm2 from the SD-OCT and SS-OCTA scans, respectively, and the mean square root of the drusen area measurements were 1.17 mm and 1.39 mm from the SD-OCT and SS-OCTA scans, respectively. In the 5 mm circle, the mean drusen area measurements were 1.89 mm2 and 2.67 mm2 from the SD-OCT and SS-OCTA scans, respectively, and the mean square root of drusen area measurements were 1.28 mm and 1.54 mm from the SD-OCT and SS-OCTA scans, respectively. Similarly, the cube root drusen volumes were larger from the SS-OCTA scans. In the center 3 mm circle, the mean drusen volume measurements were 0.09 mm3 and 0.13 mm3 from the SD-OCT and SS-OCTA scans, respectively, and the mean cube root of drusen volume measurements were 0.41 mm and 0.47 mm from the SD-OCT and SS-OCTA scans, respectively. In the center 5 mm circle, the mean ...
Purpose the objective of this paper is to describe the optical coherence tomography (OCT) characteristics of patients with full-thickness traumatic macular hole (TMH) and to correlate them with biomicroscopy findings.Methods Twelve eyes of ten consecutive patients with full-thickness TMH participated in this observational retrospective multicentre study. Patients underwent biomicroscopic fundus examination, colour fundus photography, and OCT.Results Traumatic macular hole was documented with OCT in five women and five men. Mean (range) time between trauma and macular hole (MH) diagnosis was 8.1 (1-24) months. the shape of TMHs was round in 11 (91.7%) eyes. the posterior vitreous was completely detached in six (50%) eyes, and with an operculum in one (8.3%) eye. the common findings seen on OCT were: (1) full-thickness loss of retinal tissue through the hole with sharp edges, perpendicular to the retinal pigment epithelium in five (41.7%) eyes; (2) TMH with an operculum totally detached from the ...
Mark Dunbar, OD, discusses his recent lecture on optical coherence tomography (OCT) technology. He highlights the increasing need to have OCT in an optometry office, emphasizing its importance for diagnosing vitreomacular disease as well as glaucoma.
PURPOSE: To present a technique of ocular sectioning that enables continuous histologic measurements of peripapillary retinal nerve fiber layer (RNFL) thickness in a concentric ring around the optic disc, corresponding to similar regions measured by in vivo imaging techniques.. METHODS: Two pig eyes and two normal human eyes were processed using the umbrella technique, in which peripapillary concentric ring sections were obtained, at increasing diameters, all centered on the optic disc. Each histologic ring section contains a continuous circumferential 360 degrees retinal slice, oriented approximately perpendicular to the retinal surface. Every histologic slice contains each axon of the retina, sectioned perpendicular to each axons long axis and at an equal set distance from the disc margin.. RESULTS: Ring sections from pig and human eyes are presented and correlated to known RNFL anatomy. For the two human eyes, peripapillary RNFL thickness was quantified and plotted, resulting in the ...
To evaluate choroidal vascular changes, including choriocapillaris (CC) and middle/large choroidal vessels, in retinitis pigmentosa (RP) patients using wide-angle optical coherence tomography angiography (OCTA) and to determine whether changes in the choroidal vascularity have a relationship with visual function and retinal structural changes. 34 patients with a confirmed diagnosis of RP and 48 controls were recruited. All patients underwent detailed ophthalmologic and imaging examinations, including two types of OCTA (Optovue, 3 × 3 mm, 6 × 6 mm; VG-200, 12 × 12 mm). CC defects were defined according to the choroidal vascular structure in five degrees. To evaluate middle and large choroidal vascular changes, the choroidal vascularity index (CVI), which was the luminance volume to the total choroidal volume, was used. Defects of choroidal vascularity of RP eyes were detected in comparison to control eyes. The defects were observed in the CC layer with a concentric or lobular pattern at different
Purpose: The purpose of this study was to define the morphologic differences in idiopathic and secondary epiretinal membranes (ERMs) using a time domain optical coherence tomography. ...
The National Institute on Deafness and Other Communication Disorders (NIDCD) supports research and development of innovative technologies for improving the qual...
Relative sensitivity and specificity of 10-2 visual fields, multifocal electroretinography, and spectral domain optical coherence tomography in detecting hydroxychloroquine and chloroquine retinopathy David J Browning, Chong Lee Charlotte Eye, Ear, Nose and Throat Associates, Charlotte, NC, USA Background: The purpose of this study was to determine the relative sensitivity and specificity of 10-2 visual fields (10-2 VFs), multifocal electroretinography (mfERG), and spectral domain optical coherence tomography (SD-OCT) in detecting hydroxychloroquine retinopathy.Methods: A total of 121 patients taking hydroxychloroquine (n=119) or chloroquine (n=2) with 10-2 VF, mfERG, and SD-OCT tests were retrospectively reviewed. Rates of test abnormality were determined.Results: Retinopathy was present in 14 and absent in 107. Eleven of 14 (78.6%) patients with retinopathy were overdosed. Twelve (85.7%) had cumulative dosing greater than 1,000 g. The sensitivities of 10-2 VF, mfERG, and SD-OCT in detecting
Layers imagable with optical coherence tomography[edit]. Using optical coherence tomography (OCT) there are 18 layers that can ... Spectral domain optical coherence tomography in macular diseases. Meyer, Carsten H.; Saxena, Sandeep; Sadda, SriniVas R. New ... A relatively new technology, now becoming widely available, is optical coherence tomography (OCT). This non-invasive technique ... multifocal ERG and optical coherence tomography (OCT).[73] This strategy is effective against a number of retinal diseases that ...
Optical coherence tomography. Spie Milestone Series MS. 1998;147:324-7. Romero-Borja F, Venkateswaran K, Roorda A, Hebert T. " ... Optical coherence tomography (OCT) represents a powerful clinical tool for monitoring retinal physiology in patients. OCT uses ... "Comparison between optical coherence tomography and fundus fluorescein angiography for the detection of cystoid macular edema ... with adaptive optics enhanced scanning laser ophthalmoscopy and high-speed transversal scanning optical coherence tomography". ...
He is known for his leading role in the invention of a novel medical imaging modality named optical coherence tomography that ... Boyd, Kierstan (14 October 2015). "What Is Optical Coherence Tomography?". American Academy of Ophthalmology. Retrieved 8 ... "Optical Coherence Tomography". Science. 254 (5035): 1178-1181. doi:10.1126/science.1957169. PMC 4638169. PMID 1957169. ...
CS1 maint: discouraged parameter (link) "Articles that mention Joel S. Schuman". Optical Coherence Tomography News. Retrieved ... invented the optical coherence tomography (OCT) technology. This technology, allows a quick and noninvasive 3D map of the eye, ...
1991). "Optical Coherence Tomography" (PDF). Science. 254 (5035): 1178-81. Bibcode:1991Sci...254.1178H. doi:10.1126/science. ... Another application of the Michelson interferometer is in optical coherence tomography (OCT), a medical imaging technique using ... Fercher, A.F. (1996). "Optical Coherence Tomography" (PDF). Journal of Biomedical Optics. 1 (2): 157-173. Bibcode:1996JBO.....1 ... exceeds coherence length of light beams. The nontrivial features of phase fluctuations in optical phase-conjugating mirror had ...
In 2010 the company also acquired LightLab Imaging, a company that developed optical coherence tomography technology that helps ... The device uses fractional flow reserve for measuring intra-arterial pressure and optical coherence tomography technology, ... optical coherence tomography (OCT) imaging systems; structural heart repair products; and neurostimulation devices. The ...
"winner of Optical Coherence Tomography Award". 9 January 2011. Retrieved 11 September 2016. "Giovanni J. Ughi, PhD". Google ... is one of the inventors of multimodality Optical Coherence Tomography (OCT) and Laser-induced fluorescence molecular imaging, ... "Automatic segmentation of in-vivo intra-coronary optical coherence tomography images to assess stent strut apposition and ... "Intravascular fibrin molecular imaging improves the detection of unhealed stents assessed by optical coherence tomography in ...
"NASA - Optical Coherence Tomography Technology Demonstration". www.nasa.gov. Retrieved 2018-10-13. "What's Next for Twins Study ... She has since been studying Spaceflight-Associated Neuro-Ocular Syndrome, and sent an optical coherence tomography scanner up ...
She completed her Ph.D. in biomedical engineering at Duke University in 2007, specialising in optical coherence tomography. Her ... Her research group develops new imaging devices and techniques based on optical coherence tomography, and developing point-of- ... Ellerbee, Audrey K. (2014-10-01). "Optical coherence tomography: Technology and applications". 2014 IEEE Photonics Conference: ... Her research in biomedical optics focuses on developing new imaging techniques and devices for optical coherence tomography and ...
MS patients show axonal loss in the retina and optic nerve, which can be measured by Optical coherence tomography or by ... 2007). "Optical coherence tomography and disease subtype in multiple sclerosis". Neurology. 69 (22): 2085-2092. doi:10.1093/ ... March 2009). "Optical coherence tomography differs in neuromyelitis optica compared with multiple sclerosis". Neurology. 72 (12 ... Evangelou, Nikos; Alrawashdeh, Omar S. M (2016). "Anatomy of the Retina and the Optic Nerve". Optical Coherence Tomography in ...
"Ultrahigh-resolution full-field optical coherence tomography". Applied Optics. 43 (14): 2874-2883. Bibcode:2004ApOpt..43.2874D ... The advantage of this design its ability to compensate for chromatic dispersion and other optical aberrations. In the image of ...
Abazari, Azin; Allam, Souha S.; Adamus, Grazyna; Ghazi, Nicola G. (2016-11-21). "Optical Coherence Tomography Findings in ...
Fractional flow reserve Intracoronary Optical Coherence Tomography Hector M. Garcia-Garcia, Bill D. Gogas, Patrick W. Serruys ... "Intracoronary Optical Coherence Tomography: A Comprehensive Review". JACC: Cardiovascular Interventions. 2 (11): 1035-1046. doi ...
Findings from optical coherence tomography were normal. Amsler grid test results were highly variable, and the locations of ...
Optical Coherence Tomography Resolution 0.25 μm Axial: 0.25-0.5 μm Lateral: 1 μm ... "Optical Spectroscopy and Imaging for the Noninvasive Evaluation of Engineered Tissues". Tissue Engineering Part B: Reviews. 14 ...
The optical contrast of gas vesicles also enables them to serve as contrast agents in optical coherence tomography, with ... "Biomolecular Contrast Agents for Optical Coherence Tomography" (PDF). bioRxiv. doi:10.1101/595157. S2CID 133072739. Shapiro MG ...
... where he has pioneered new optical imaging technologies in the fields of optical coherence tomography, multi-photon microscopy ... "CAREER: Functional Optical Coherence Tomography for Neural Imaging". www.nsf.gov. Retrieved 2017-12-12. "Hans Sigrist Prize ... 2011). "Handheld Optical Coherence Tomography Scanner for Primary Care Diagnostics". IEEE Trans. Biomed. Eng. 58 (3): 741-744. ... While at MIT, he was involved in the invention and early development of optical coherence tomography (OCT). Boppart started the ...
... optical coherence tomography can offer unique benefits. Optical coherence tomography angiography can help the physician see if ... Fundus autofluorescence and optical coherence tomography angiography are imaging modalities that can be used in the diagnosis. ... "Optical Coherence Tomography in Age-related Macular Degeneration". AMD book. Retrieved 8 December 2019. CS1 maint: discouraged ... While fluorescein angiography and optical coherence tomography are today well established for diagnosing and tracking ...
High-speed optical coherence tomography of corneal opacities. Ophthalmology. 2007 Jul;114(7):1278-85. Plesea et al. Direct ... OCT Biomicroscopy is the use of optical coherence tomography (OCT) in place of slit lamp biomicroscopy to examine the ... Keratoconus diagnosis with optical coherence tomography pachymetry mapping. Ophthalmology 2008 Dec;115(12):2159-66. Eye ... Detailed visualization of the anterior segment using fourier-domain optical coherence tomography. Arch Ophthalmol 2008 June;126 ...
"Solar retinopathy and associated optical coherence tomography findings." Archived 2006-09-27 at the Wayback Machine Clin Exp ...
Optical coherence tomography (OCT). References[edit]. *^ Myron Yanoff; Jay S. Duker (6 November 2013). Ophthalmology: Expert ... An optical coherence tomography (OCT) scan of a macula at 800nm, with an axial resolution of 3µm ...
Optical Coherence Tomography: A Novel Imaging Method for Post-lumpectomy Breast Margin Assessment-A Multi-reader Study. Acad ... 2007). Ultrahigh-resolution optical coherence tomography at 1.15 μm using photonic crystal fiber with no zero-dispersion ... An automated 3D registration method for optical coherence tomography volumes. Conf Proc IEEE Eng Med Biol Soc. 2014;2014:3873‐ ... Highly phase-stable 200 kHz swept-source optical coherence tomography based on KTN electro-optic deflector. Biomed Opt Express ...
Chen JC, Lee LR (November 2004). "Solar retinopathy and associated optical coherence tomography findings" (PDF). Clin Exp Optom ...
Some of these locations use a fundus camera, others use both fundus and optical coherence tomography (OCT) imaging devices, and ... Recently, emerging retinal imaging modalities such as optical coherence tomography are capable of producing digital images of ... Kelly, SP; I Wallwork; D Haider; K Qureshi (2011). "Teleophthalmology with optical coherence tomography imaging in community ... Retrieved 2012-12-15{{inconsistent citations}} "Teleophthalmology with optical coherence tomography imaging in the community". ...
Chen JC, Lee LR (2004). "Solar retinopathy and associated optical coherence tomography findings" (PDF). Clin Exp Optom. 87 (6 ... Prolonged optical exposure to sunlight, especially intense ultraviolet light, may be linked to cortical cataracts, and high ...
Ah-kee, Elliott; Oladiwura, Dilys; Lim, Lik Thai; Scott, Angus (2014-05-19). "Macular optical coherence tomography findings ...
Optical coherence tomography of fingertip See also[edit]. *Skin repair. References[edit]. *^ Young, Barbara (2014). Wheater's ...
Optical coherence tomography‎ (6 P). Pages in category "Laser medicine". The following 36 pages are in this category, out of 36 ...
Optical coherence tomography‎ (6 P). *. ► Opticians‎ (2 C, 158 P). P. *. ► Science of photography‎ (4 C, 89 P) ...
Optical/Laser. *Optical tomography *Optical coherence tomography. *Confocal microscopy. *Endomicroscopy. *Orthogonal ... In computed tomography (CT scanning) an X-ray source and its associated detectors rotate around the subject which itself moves ... Herman GT (2009). Fundamentals of Computerized Tomography: Image Reconstruction from Projections (2nd ed.). Springer. ISBN 978- ... Computed tomography or CT scan (previously known as CAT scan, the "A" standing for "axial") uses ionizing radiation (x-ray ...
Optical coherence tomography. *Electrodiagnosis: Electrooculography. *Electroretinography. *Electronystagmography. Eye ...
Optical/Laser. *Optical tomography *Optical coherence tomography. *Confocal microscopy. *Endomicroscopy. *Orthogonal ... Optical computed tomography for imaging the breast: first look // Proc. SPIE, 2000, Vol. 4082, p. 40-45. ... Computed tomography laser mammography (CTLM) is the trademark of Imaging Diagnostic Systems, Inc. (IDSI, United States) for its ... It is optical molecular imaging for hemoglobin both oxygenated and deoxygenated. The technology uses laser in the same way ...
Optical coherence tomography. *Eye care professional. *Eye disease. *Refractive error. *Accommodation. *Physiological Optics ...
A main application for FDML lasers is optical coherence tomography. Practical mode-locked lasers[edit]. In practice, a number ... A new laser operating regime and applications for optical coherence tomography," Opt. Express 14, 3225-3237 (2006) ... Optical Data Storage uses lasers, and the emerging technology of 3D optical data storage generally relies on nonlinear ... This uses a nonlinear optical process, the optical Kerr effect, which results in high-intensity light being focussed ...
A patented method that utilizes optical coherence tomography to measure the thickness of the nerve fiber layer and infers ICP ... along and in part inside of the optical nerve. The impediment of venous return causes visible changes in the eye fundus (venous ...
Optical coherence tomography. *Electrodiagnosis: Electrooculography. *Electroretinography. *Electronystagmography. Eye ...
Optical/Laser. *Optical tomography *Optical coherence tomography. *Confocal microscopy. *Endomicroscopy. *Orthogonal ...
Using optical coherence tomography to produce detailed images of the brain or other soft tissue, through a "window" made of ...
These make it especially useful for wide-angle camera lenses, microscopy, and the core part of optical fibers.[62][63] It has ... and more recently donor electron spins in germanium has been shown to have very long coherence times.[79] ... "A Bismuth Germanate-Avalanche Photodiode Module Designed for Use in High Resolution Positron Emission Tomography". IEEE ... "Chapter III: Optical Fiber For Communications" (PDF). Stanford Research Institute. Retrieved 2008-08-22.. ...
Optical/Laser. *Optical tomography *Optical coherence tomography. *Confocal microscopy. *Endomicroscopy. *Orthogonal ...
Optical laser. *Optical tomography *Optical coherence tomography. *Confocal microscopy. *Endomicroscopy. Thermography. *non- ... The stage could move along the optical axis, allowing optical serial sections.[28] ... is an optical imaging technique for increasing optical resolution and contrast of a micrograph by means of using a spatial ... but also by the optical properties of the specimen. The thin optical sectioning possible makes these types of microscopes ...
Optical Coherence Tomography (OCT) is another NIR medical imaging technique capable of 3D imaging with high resolution on par ... Using optical coherence to measure photon pathlength allows OCT to build images of live tissue and clear examinations of tissue ... The application in functional mapping of the human cortex is called diffuse optical tomography (DOT), near-infrared imaging ( ... NIRI) or functional NIRS (fNIR/fNIRS).[12] The term diffuse optical tomography is used for three-dimensional NIRS. The terms ...
Optical/Laser. *Optical tomography *Optical coherence tomography. *Confocal microscopy. *Endomicroscopy. *Orthogonal ... Traditionally the images produced with barium contrast are made with plain-film radiography, but computed tomography is also ... Barium studies and computer tomography are the most common tools used to diagnose gastrointestinal lymphoma. Barium contrast is ... Barium fluoroscopic examinations have some advantages over computed tomography and magnetic resonance techniques, such as ...
... single-photon emission computed tomography (SPECT), near-infrared spectroscopy (NIRS), and event-related optical signal (EROS ... A tutorial on analysis of ongoing, evoked, and induced neuronal activity: Power spectra, wavelet analysis, and coherence ... EEG has also been combined with positron emission tomography. This provides the advantage of allowing researchers to see what ... EEG does not involve exposure to radioligands, unlike positron emission tomography.[28] ...
Optical coherence tomography. *Eye care professional. *Eye disease. *Refractive error. *Accommodation. *Physiological Optics ...
Optical coherence tomography. *Electrodiagnosis: Electrooculography. *Electroretinography. *Electronystagmography. Eye ...
Optical/Laser. *Optical tomography *Optical coherence tomography. *Confocal microscopy. *Endomicroscopy. *Orthogonal ... T2* decay is caused by magnetized nuclei in a volume of space losing magnetic coherence (transverse magnetization) from both ... "Mapping brain networks in awake mice using combined optical neural control and fMRI". Journal of Neurophysiology. 105 (3): ... "Characterization of the functional MRI response temporal linearity via optical control of neocortical pyramidal neurons" ...
Advances in Magnetic and Optical Resonance. 12. pp. 1-89. doi:10.1016/b978-0-12-025512-2.50004-x. ISBN 9780120255122. .. ... weighted images, contrast is produced by measuring the loss of coherence or synchrony between the water protons. When water is ... where it is a serious candidate to replace positron emission tomography as the 'gold standard' for this type of disease. ... the mathematics used deploys both probability distributions and a classic bit of geometric tomography and vector math developed ...
Optical coherence tomography for diagnosing skin cancer in adults PMID 30521690 https://doi.org/10.1002/14651858.CD013189 ... Optical reading aids for children and young people with low vision PMID 25738963 https://doi.org/10.1002/14651858.CD010987.pub2 ...
Optical/Laser. *Optical tomography *Optical coherence tomography. *Confocal microscopy. *Endomicroscopy. *Orthogonal ... In contrast, SPECT and positron emission tomography (PET) form 3-dimensional images, and are therefore classified as separate ... Detectors coated with materials which scintillate when subjected to gamma rays are scanned with optical photon detectors and ... A special type of gamma camera is the SPECT (Single Photon Emission Computed Tomography). Another medical scintillography ...
... optical coherence tomography and ultrasound.[2][5][9][7] For example, indocyanine green angiography may detect continuing ...
Optical laser. *Optical tomography *Optical coherence tomography. *Confocal microscopy. *Endomicroscopy. Thermography. *non- ... Analytical techniques, much like the reconstruction of computed tomography (CT) and single-photon emission computed tomography ... 2010). "Clinical value of 18F-fluorodihydroxyphenylalanine positron emission tomography/computed tomography (18F-DOPA PET/CT) ... Positron-emission tomography (PET)[1] is a nuclear medicine functional imaging technique that is used to observe metabolic ...
In contrast, optical coherence tomography, in its classical version, uses light with a short coherence time. ... optical coherence tomography and telescope interferometers (astronomical optical interferometers and radio telescopes). ... Measurement of spectral coherence[edit]. Measurement of the spectral coherence of light requires a nonlinear optical ... In that case, coherence is a function of wavenumber (spatial frequency). The coherence varies in the interval 0. ⩽. γ. x. y. 2 ...
These include elastography with optical coherence tomography[27] (i.e. light). Tactile imaging involves translating the results ... 1] A Review of Optical Coherence Elastography: Fundamentals, Techniques and Prospects. IEEE Journal of Selected Topics in ...
Optical/Laser. *Optical tomography *Optical coherence tomography. *Confocal microscopy. *Endomicroscopy. *Orthogonal ... For non-medical computed tomography, see industrial computed tomography scanning. For non-X-ray tomography, see Tomography. ... X-ray computed tomography (X-ray CT), computerized axial tomography scan (CAT scan),[2] computer aided tomography, computed ... A CT scan,[1] also known as computed tomography scan, and formerly known as a computerized axial tomography scan or CAT scan,[3 ...
... optical coherence tomography, the multispectral imaging technique, thermography, electrical bio-impedance, tape stripping and ...
Optical coherence tomography. *Eye care professional. *Eye disease. *Refractive error. *Accommodation. *Physiological Optics ...
Optical/Laser. *Optical tomography *Optical coherence tomography. *Confocal microscopy. *Endomicroscopy. *Orthogonal ... Other imaging technologies such as quantitative computed tomography (QCT) are capable of measuring the bone's volume, and are, ...
4. Optical Coherence Tomography …this is what we got… * 5. Interpretation of OCT imagesOuter retina 250 !m 500 !m • The OCT ... optical coherence tomography interprentation * 1. Interpretation of the OCT Image (and some new developments) B. Jeroen ... 3. Optical Coherence Tomography This is what we wanted… * ... Optical coherence tomography by Shweta Prasad 8668 views * ... İnterpretation of optic coherence t... by Sinan çalışkan 36942 views * OCT: Interpretacion clínica by Alejandro Villalobos ...
G. J. Tearney, M. E. Brezinski, B. E. Bouma et al., "In vivo endoscopic optical biopsy with optical coherence tomography," ... J. Welzel, "Optical coherence tomography in dermatology: a review," Skin Research and Technology, vol. 7, no. 1, pp. 1-9, 2001. ... MEMS-Based Endoscopic Optical Coherence Tomography. Jingjing Sun and Huikai Xie Department of Electrical and Computer ... J. G. Fujimoto, "Optical coherence tomography for ultrahigh resolution in vivo imaging," Nature Biotechnology, vol. 21, no. 11 ...
Optical coherence tomography for ocular surface and corneal diseases: a review The advent of optical coherence tomography (OCT ... Clinical Applications of Optical Coherence Tomography. Edited by: Jianhua Wang. Optical coherence tomography (OCT) has been ... Optical coherence tomography angiography at the acute phase of optic disc edema The differential diagnosis of optic disc edema ... Spectral domain optical coherence tomography (SD-OCT) was a useful tool to study accommodation in human eye, but the maximum ...
Optical coherence tomography in dermatology: a review.. Welzel J1.. Author information. 1. Department of Dermatology, Medical ... Optical coherence tomography (OCT) is a non-invasive technique for morphological investigation of tissue. Since its development ... The in vivo OCT images of human skin show a strong scattering from tissue with a few layers and some optical inhomogeneities. ...
Optical coherence tomography (OCT) is an intra-coronary diagnostic technique that provides detailed imagings of blood vessels ... Optical coherence tomography. Science. 1991;254:1178-81.CrossRefPubMedPubMedCentralGoogle Scholar ... Characterization of human atherosclerosis by optical coherence tomography. Circulation. 2002;106:1640-5.CrossRefPubMedGoogle ... Optical coherence tomography (OCT) is an intra-coronary diagnostic technique that provides detailed imagings of blood vessels ...
... is the optical analog of ultrasound imaging and is emerging as a powerful imaging technique that enables non-invasive, in vivo ... Optical coherence tomography (OCT) is the optical analog of ultrasound imaging and is emerging as a powerful imaging technique ... Optical Coherence Tomography. Technology and Applications. Editors: Drexler, Wolfgang, Fujimoto, James G. (Eds.) ... "This is a comprehensive review of the current status of optical coherence tomography (OCT) technology and its applications in ...
Intraoperative optical coherence tomography (iOCT) was recently introduced as a new modality for ophthalmic surgeries. It ... Optical coherence tomography. Fig. 1. Schematic overview over a spectral domain intraoperative optical coherence tomography ... Automatic intraoperative optical coherence tomography positioning. *Matthias Grimm. ORCID: orcid.org/0000-0002-3433-40201. , ... Grimm, M., Roodaki, H., Eslami, A. et al. Automatic intraoperative optical coherence tomography positioning. Int J CARS 15, 781 ...
... coherence_tomography rel=noreferrer nofollow,Optical coherence tomography,/a, of my ,a href=http://en.wikipedia.org/wiki/ ... One of the tests was ,a href=http://en.wikipedia.org/wiki/Optical_ ... Optical coherence tomography of my retina I have the start of glaucoma in my right eye, and recently got it tested in some ... One of the tests was Optical coherence tomography of my retina. I was quite interested, since I am an engineer and have been ...
Optical Biopsy with a Short Photonic Needle? I.K. Jang, MD Massachusetts General Hospital Harvard Medical School The 3rd ... Optical coherence tomography optical biopsy with a short photonic needle * 1. Optical Coherence Tomography: Optical Biopsy with ... 2. Optical Coherence TomographyOptical analog of ultrasound • Cross-sectional imaging • 10 µm resolution • 2 mm penetration ... 3. MGH OCT System Technical Data Optical wavelength : Image acquisition rate : Catheter: Axial Resolution : Transverse ...
... Blake M. Hampton,1 Christopher M. Aderman,2 Harry W. ... Blake M. Hampton, Christopher M. Aderman, Harry W. Flynn Jr., and Jayanth Sridhar, "Optical Coherence Tomography Angiography of ...
... assemblies and components that are critical to medical imaging systems fabricators for ophthalmic optical coherence tomography ... Optical Coherence Tomography (OCT) Delay Line. The OCT optical delay line and its variable small form-factor model from G&H is ... For more information on the many high-tech optical assemblies and components for ophthalmic optical coherence tomography, visit ... acousto-optic product that is ideal for applications such as laser doppler velocimetry and optical coherence tomography. The ...
Tag: optical coherence tomography. Posted on June 22, 2012. January 3, 2016. ... This set of images (click the image above to enlarge) are optical coherence tomography (OCT) images of retained perfluoro- ...
Optical coherence tomography is the most commonly performed ancillary test in eye care. ... This is a case-based atlas intended to teach the reader how to interpret the results of optical coherence tomography or OCT in ... Atlas of Optical Coherence Tomography for Glaucoma is a case-based atlas intended to teach the reader how to interpret the ... Atlas of Optical Coherence Tomography for Glaucoma. Editors. * Donald L. Budenz Copyright. 2020. Publisher. Springer ...
... optical coherence tomography angiography is an imaging technique that uses light... ... Define optical coherence tomography angiography: Also known as OCT-A, ... optical coherence tomography angiography. Also known as OCT-A, optical coherence tomography angiography is an imaging technique ... Optical Fabrication. Methods, materials and measurement techniques "Largely unchanged for centuries, optical... ...
Tracking Optical Coherence Tomography. The safety and scientific validity of this study is the responsibility of the study ...
Swept-source optical coherence tomography (SS-OCT) image demonstrates some of the many abnormalities that can be present in a ... Swept-source optical coherence tomography (SS-OCT) image demonstrates some of the many abnormalities that can be present in a ...
Optical coherence tomography to guide percutaneous coronary intervention. Number. IPG481. Date issued. February 2014. Other ... The evidence on the safety of optical coherence tomography (OCT) to guide percutaneous coronary intervention (PCI) shows no ... NICE encourages further research into optical coherence tomography (OCT) to guide PCI compared against percutaneous coronary ...
Spectral Optical Coherence Tomography therefore provides a much wider sa … ... Ophthalmic imaging by spectral optical coherence tomography Am J Ophthalmol. 2004 Sep;138(3):412-9. doi: 10.1016/j.ajo.2004.04. ... Spectral Optical Coherence Tomography therefore provides a much wider safety margin than the traditional method and allows ... Purpose: To demonstrate two novel ophthalmic imaging techniques based on fast Spectral Optical Coherence Tomography (SOCT). ...
A relatively recent implementation of optical coherence tomography, frequency-domain optical coherence tomography, provides ... Optical coherence tomography (OCT) is an imaging technique that uses low-coherence light to capture micrometer-resolution, two ... Optical coherence tomography is based on low-coherence interferometry, typically employing near-infrared light. The use of ... Optical coherence tomography is one of a class of optical tomographic techniques.[citation needed] Commercially available ...
If your eye doctor needs to examine your retina, she or he may suggest optical coherence tomography. OCT is a noninvasive test ...
Doppler optical coherence tomography (OCT) can image tissue structure and blood flow at micrometer-scale resolution but has ... Doppler optical coherence tomography (OCT) can image tissue structure and blood flow at micrometer-scale resolution but has ... Tomography, Optical Coherence / instrumentation*, methods. Ultrasonography, Interventional / instrumentation*, methods. From ... Next Document: Optical levitation and manipulation of stuck particles with pulsed optical tweezers.. ...
Fourier-domain optical coherence tomography: recent advances toward clinical utility.. Bouma BE1, Yun SH, Vakoc BJ, Suter MJ, ... Schematic layout of typical polarization-diverse Fourier-domain optical coherence tomography systems. (a) Spectral-domain ... With the advent of Fourier-domain techniques, optical coherence tomography (OCT) has advanced from high-resolution point ... and novel optical and signal processing strategies. In recent cardiovascular, ophthalmic, and gastrointestinal clinical studies ...
Low-coherence interferometry and optical coherence tomography for image-guided surgical treatment of solid tumors. ... Low-coherence interferometry and optical coherence tomography for image-guided surgical treatment of solid tumors. ... Dual window processing schemes for spectroscopic optical coherence tomography (OCT) and fourier domain low coherence ... Multiple window processing schemes for spectroscopic optical coherence tomography (oct) and fourier domain low coherence ...
Noninvasive Blood Glucose Monitoring With Optical Coherence Tomography. Kirill V. Larin, Mohsen S. Eledrisi, Massoud Motamedi, ... Noninvasive Blood Glucose Monitoring With Optical Coherence Tomography. Kirill V. Larin, Mohsen S. Eledrisi, Massoud Motamedi, ... Noninvasive Blood Glucose Monitoring With Optical Coherence Tomography Message Subject (Your Name) has forwarded a page to you ... Noninvasive Blood Glucose Monitoring With Optical Coherence Tomography. A pilot study in human subjects. ...
... the Global Optical Coherence Tomography Equipments Market is valued at USD XX million in 2016 and is expected to reach USD XX ... 1.2 Optical Coherence Tomography Equipments Segment by Type (Product Category). 1.2.1 Global Optical Coherence Tomography ... 1.4 Global Optical Coherence Tomography Equipments Market by Region (2012-2022). 1.4.1 Global Optical Coherence Tomography ... 1 Optical Coherence Tomography Equipments Market Overview. 1.1 Product Overview and Scope of Optical Coherence Tomography ...
The emergence of Optical Coherence Tomography (OCT) in recent years has revolutionized the way we see the retina. Providing, in ... Atlas of Optical Coherence Tomography of Macular Diseases By Vishali Gupta. , Amod Gupta. , Mangat R. Dogra. ... The emergence of Optical Coherence Tomography (OCT) in recent years has revolutionized the way we see the retina. Providing, in ... Containing nearly 900 scans of both normal and diseased appearances, most in full color, Atlas of Optical Coherence Tomography ...
Corresponding optical coherence tomogram illustrating the subretinal fluid accumulation (orange arrow). Accumulation of ...
Noninvasive Blood Glucose Monitoring With Optical Coherence Tomography. Kirill V. Larin, Mohsen S. Eledrisi, Massoud Motamedi, ... Noninvasive Blood Glucose Monitoring With Optical Coherence Tomography. Kirill V. Larin, Mohsen S. Eledrisi, Massoud Motamedi, ... Noninvasive Blood Glucose Monitoring With Optical Coherence Tomography Message Subject (Your Name) has forwarded a page to you ... In this article we tested the novel optical coherence tomography (OCT) technique for noninvasive blood glucose monitoring in ...
"Temporal coherence and time-frequency distributions in spectroscopic optical coherence tomography". Journal of the Optical ... Spectroscopic optical coherence tomography (SOCT) is an optical imaging and sensing technique, which provides localized ... Optical coherence tomography : technology and applications. Drexler, Wolfgang,, Fujimoto, James G. (Second ed.). Cham. ISBN 978 ... spectroscopic information of a sample based on the principles of optical coherence tomography (OCT) and low coherence ...
Optical Coherence Tomography) scan today. The OCT eye test only takes a few seconds and lets our experts look at the health of ... An optical coherence tomography scan (commonly referred to as an OCT scan) helps us to view the health of your eyes in greater ...
  • One of the tests was Optical coherence tomography of my retina . (flickr.com)
  • citation needed] Commercially available optical coherence tomography systems are employed in diverse applications, including art conservation and diagnostic medicine, notably in ophthalmology and optometry where it can be used to obtain detailed images from within the retina. (wikipedia.org)
  • Optical coherence tomography (OCT) is a means of noninvasive evaluation of the retina and optic nerve through imaging the back of the eye. (criver.com)
  • If your eye doctor needs to examine your retina, she or he may suggest optical coherence tomography. (sutterhealth.org)
  • The emergence of Optical Coherence Tomography (OCT) in recent years has revolutionized the way we see the retina. (routledge.com)
  • Optical coherence tomography angiography (OCTA) is a noninvasive imaging technique that, in contrast to dye-based angiography, is faster and depth-resolved, allowing in some cases for more precise evaluation of the vascular plexuses of the retina and choroid. (healio.com)
  • The novel Coaxial Optical Coherence Tomography (OCT) System is designed to visualize both structures of the retina and choroid. (bioportfolio.com)
  • Optical Coherence Tomography (OCT) enables non-invasive imaging of the retina and is used to diagnose and manage ophthalmic diseases including glaucoma. (doaj.org)
  • Optical Coherence Topography (OCT) image, enabling the detailed analysis of the retina and macula structures. (sciencephoto.com)
  • Optical coherence tomography (OCT) is a fast and noninvasive tool for examining the retina in cross sectional images that correlate reasonably with the retinal histology. (thefreelibrary.com)
  • Miller, "Distinguishing white dot syndromes with patterns of choroidal hypoperfusion on optical coherence tomography angiography," Ophthalmic Surgery, Lasers and Imaging Retina, vol. (thefreedictionary.com)
  • OCT uses low-coherence interferometry to produce a two-dimensional image of optical scattering from internal tissue microstructures in a way that is analogous to ultrasonic pulse-echo imaging. (sciencemag.org)
  • Optical coherence tomography is based on low-coherence interferometry, typically employing near-infrared light. (wikipedia.org)
  • citation needed] Starting from Adolf Fercher and colleagues' work on low-, partial coherence or white-light interferometry for in vivo ocular eye measurements in Vienna in the 1980s, imaging of biological tissue, especially of the human eye, was investigated in parallel by multiple groups worldwide. (wikipedia.org)
  • OCT is based on low-coherence interferometry. (wikipedia.org)
  • page needed] In conventional interferometry with long coherence length (i.e., laser interferometry), interference of light occurs over a distance of meters. (wikipedia.org)
  • Spectroscopic optical coherence tomography (SOCT) is an optical imaging and sensing technique, which provides localized spectroscopic information of a sample based on the principles of optical coherence tomography (OCT) and low coherence interferometry. (wikipedia.org)
  • Optical coherence tomography (OCT) is a non-contact, high resolution biomedical imaging technique that uses low coherence interferometry to generate cross-sectional images of tissue. (mit.edu)
  • Optical coherence tomography (OCT) is a noninvasive, low coherent interferometry technique that uses backscattered light to generate tomographic images of tissue microstructures. (spiedigitallibrary.org)
  • OCT employs low-coherence interferometry to create cross-sectional images that reveal sub-surface details of the tissues of interest. (jefferson.edu)
  • The Bioptigen Envisu R2210 system is a non-invasive technique that is used to detect and monitor morphological changes of the ocular tissue This OCT utilizes low-coherence interferometry to create cross-sectional images that reveal sub-surface detail of the tissues. (jefferson.edu)
  • Optical coherence tomography (OCT) is the optical analog of ultrasound imaging and is emerging as a powerful imaging technique that enables non-invasive, in vivo, high resolution, cross-sectional imaging in biological tissue. (springer.com)
  • A technique called optical coherence tomography (OCT) has been developed for noninvasive cross-sectional imaging in biological systems. (sciencemag.org)
  • High-speed anterior segment optical coherence tomography (OCT) offers a non-contact method for high resolution cross-sectional and three-dimensional imaging of the cornea and the anterior segment of the eye. (indigo.ca)
  • While standard electronic techniques are adequate for processing ultrasonic echoes that travel at the speed of sound, interferometric techniques are required to extract the reflected optical signals from the infrared light used in OCT. The output, measured by an interferometer, is computer processed to produce high-resolution, real time, cross sectional or 3-dimensional images of the tissue. (medgadget.com)
  • Two-dimensional (2D), cross-sectional OCT images of tissue are constructed by scanning the optical beam and performing axial measurements of light echoes at different transverse positions. (optics.org)
  • OCT is akin to noninvasive tissue "biopsy"-it provides in vivo cross-sectional views (tomography) of internal tissue structures similar to tissue sections under a microscope [ 2 , 3 ]. (intechopen.com)
  • Optical coherence tomography (OCT), a new imaging technology that allows noninvasive cross-sectional imaging, has high sensitivity for diagnosing cervical cancer, but low specificity, according to a study published in the March issue of Lasers in Surgery and Medicine. (contemporaryobgyn.net)
  • MONDAY, April 4 (HealthDay News) -- Optical coherence tomography (OCT), a new imaging technology that allows noninvasive cross-sectional imaging, has high sensitivity for diagnosing cervical cancer, but low specificity, according to a study published in the March issue of Lasers in Surgery and Medicine . (contemporaryobgyn.net)
  • Optical coherence tomography: a new tool for glaucoma diagnosis," Current Opinion in Ophthalmology , vol. 6, no. 2, pp. 89-95, 1995. (hindawi.com)
  • Atlas of Optical Coherence Tomography for Glaucoma is a case-based atlas intended to teach the reader how to interpret the results of OCT in glaucoma patients and glaucoma suspects. (springer.com)
  • To investigate the potential of handheld optical coherence tomography (HH-OCT) in assessing the anterior segment of the eye in patients with primary congenital glaucoma. (nature.com)
  • today announced the development of software that uses existing Spectral Domain Optical Coherence Tomography (SD-OCT) images to assist ophthalmologists and optometrists in diagnosing retinal and optic nerve disease such as glaucoma. (thefreedictionary.com)
  • Glaucoma detection ability of ganglion cell-inner plexiform layer thickness by spectral-domain optical coherence tomography in high myopia. (thefreedictionary.com)
  • Does Foveal Position Relative to the Optic Disc Affect Optical Coherence Tomography Measurements in Glaucoma? (thefreedictionary.com)
  • We hypothesize that there is a correlation between retinal thickness and capillary network perfusion measured by the novel optical coherence tomography angiography (OCTA) technique in glaucoma patients. (arvojournals.org)
  • The in vivo OCT images of human skin show a strong scattering from tissue with a few layers and some optical inhomogeneities. (nih.gov)
  • A new generation OCT technology has now been developed, representing a quantum leap in resolution and speed, achieving in vivo optical biopsy, i.e. the visualization of tissue architectural morphology in situ and in real time. (springer.com)
  • Newly developed Cell OCT, an approach to full-field optical coherence tomography, has enabled researchers to image breast-cancer tissue with histology-like results. (laserfocusworld.com)
  • Fourier-domain optical coherence tomography: recent advances toward clinical utility. (nih.gov)
  • Schematic layout of typical polarization-diverse Fourier-domain optical coherence tomography systems. (nih.gov)
  • We have combined Fourier-domain optical coherence tomography (OCT) with a closed-loop Adaptive Optics (AO) system. (spie.org)
  • Confocal microscopy, another optical technique, typically penetrates less deeply into the sample but with higher resolution. (wikipedia.org)
  • Directions of interest include super-resolution microscopy, multimodal approaches, linear and nonlinear quantitative imaging, phase-sensitive detection of optical signatures and the integration of microscopy and OCT with endoscopic applications. (osa.org)
  • Full-field Cell OCT relies on low-coherence interference microscopy. (laserfocusworld.com)
  • Intraoperative optical coherence tomography (iOCT) was recently introduced as a new modality for ophthalmic surgeries. (springer.com)
  • Recently, intraoperative optical coherence tomography (iOCT) has been introduced as a new modality to assist eye surgeons during ophthalmic surgery. (springer.com)
  • In this work, an automated positioning system is proposed for an intraoperative optical coherence tomography device in the context of the anterior segment (AS) of the eye. (springer.com)
  • The aim of this study was to describe intraoperative optical coherence tomography ( OCT ) as an adjunctive device for peripheral synechiolysis in a post-penetrating keratoplasty patient. (leica-microsystems.com)
  • Containing nearly 900 scans of both normal and diseased appearances, most in full color, Atlas of Optical Coherence Tomography of Macular Diseases covers how to use Stratus OCT for diagnosing various macular disorders, identifying correct therapeutic approaches and monitoring the responses to therapies and interventions. (routledge.com)
  • Furthermore, the wide use of optical coherence tomography angiography (OCTA) boosts the OCT field from structural imaging to vascular imaging, which provides an opportunity in quantitative analysis of both the ocular structure and vasculature. (biomedcentral.com)
  • There are two forms of system implementation of optical coherence tomography angiography (OCTA) in ophthalmic imaging, i.e., spectral domain (SD-) and swept source OCTA (SS-OCTA). (biomedcentral.com)
  • To review the clinical and research value of optical coherence tomography angiography (OCTA) in the field of neurology. (biomedcentral.com)
  • The aim of the present study was to examine the effects of preeclampsia on posterior ocular blood flow through optic coherence tomography angiography (OCTA). (bioportfolio.com)
  • The advent of optical coherence tomography (OCT) imaging has changed the way ophthalmologists image the ocular surface and anterior segment of the eye. (biomedcentral.com)
  • Posterior ocular blood flow in preeclamptic patients evaluated with optical coherence tomography angiography. (bioportfolio.com)
  • Intraoperative ocular coherence tomography (iOCT) is a useful asset when performing macular surgery and other vitreoretinal procedures. (leica-microsystems.com)
  • We demonstrate ultrahigh resolution optical coherence tomography using the continuum generation in an air-silica microstructure fiber. (spie.org)
  • The global market for optical coherence tomography (OCT) grew from $580.8 million in 2011 to $645.4 million in 2012 and is predicted to increase to nearly $1.1 billion by 2017, at a CAGR of 10.4% from 2012 to 2017. (bccresearch.com)
  • Swept-source optical coherence tomography (SS-OCT) image demonstrates some of the many abnormalities that can be present in a highly myopic eye. (aao.org)
  • Importantly, the PIC receiver supports the very high electrical frequencies and wide range of optical wavelengths required for swept-source OCT while also enabling what is known as quadrature detection, which doubles the OCT imaging range for a given data acquisition speed. (eurekalert.org)
  • To determine the early signs of posterior staphylomas in highly myopic eyes of younger subjects by swept-source ultra-widefield optical coherence tomography (WF-OCT). (bioportfolio.com)
  • This book gives a clinical context to optical coherence tomography (OCT) findings, while considering the differential diagnosis and providing patient management guidance. (ebooks.com)
  • We present the spectral optical coherence tomography (OCT) findings in two patients with unilateral AOFVD. (nih.gov)
  • Optic nerve head measurements extracted from optical coherence tomography (OCT) show promise for monitoring clinical conditions with elevated optic nerve heads. (biomedcentral.com)
  • In this paper we present spatially mapped point-spread function (PSF) measurements of an optical coherence tomography (OCT) instrument and subsequent spatial deconvolution. (osapublishing.org)
  • Optical coherence tomography (OCT) is a non-invasive technique for morphological investigation of tissue. (nih.gov)
  • Optical coherence tomography (OCT) is an imaging technique that uses low-coherence light to capture micrometer-resolution, two- and three-dimensional images from within optical scattering media (e.g., biological tissue). (wikipedia.org)
  • Doppler optical coherence tomography (OCT) can image tissue structure and blood flow at micrometer-scale resolution but has limited imaging depth. (biomedsearch.com)
  • Further, 2 d {\textstyle 2d} is the optical path length difference so that d {\textstyle d} is the assigned depth location in the tissue. (wikipedia.org)
  • Among the efforts of this group are the development and application of methods that optimize the optical examination of cellular and tissue biology through increased spatial resolution, higher acquisition speeds, improved penetration depths and maximized contrast. (osa.org)
  • Optical coherence tomography (OCT) is an imaging method which can image with micrometer-scale resolution up to a few millimeters deep into, for example, living biological tissues and preserved tissue samples. (google.es)
  • A range of extensions enable optical coherence tomography (OCT) to achieve functional imaging, providing useful information about tissue dynamics and expanding OCT's clinical relevance. (laserfocusworld.com)
  • The OCT optical components mainly consist of a single-mode fiber, a gradient index lens for light-beam focusing, and a right-angled prism for reflecting light into biological tissue. (spiedigitallibrary.org)
  • OCT can function as a type of "optical biopsy", imaging tissue microstructure in situ and in real time without removing and processing tissue specimens. (optics.org)
  • Wide-field Optical Coherence Tomography Imaging of Excised Breast Tissue. (clinicaltrials.gov)
  • The Use of Vibrational Optical Coherence Tomography in Matching Host Tissue and Implant Mechanical Properties. (scirp.org)
  • Optical Coherence Tomography (OCT) is a non-invasive, non-contact imaging modality used to visualize and monitor changes to the morphology of biological tissue. (jefferson.edu)
  • Optical coherence tomography (OCT) is a non-invasive imaging modality that provides depth-resolved, high-resolution images of tissue microstructure in real-time. (columbia.edu)
  • Optical Coherence Tomography (OCT) has been used in biomedical applications as a method to non-invasively detect changes occurring in tissue such as the detection of skin cancer. (csir.co.za)
  • To demonstrate two novel ophthalmic imaging techniques based on fast Spectral Optical Coherence Tomography (SOCT). (nih.gov)
  • The general principles behind SOCT, arise from the large optical bandwidths involved in OCT, where Information on the spectral content of backscattered light can be obtained by detection and processing of the interferometric OCT signal. (wikipedia.org)
  • The following discussion of techniques for quantitatively obtaining localized optical properties using SOCT is a summary of the concepts discussed in Bosscharrt et. (wikipedia.org)
  • The aim of this article is to demonstrate an application of Spectral Optical Coherence Tomography SOCT for visualization of the anterior segment of the human eye. (spie.org)
  • NICE encourages further research into optical coherence tomography (OCT) to guide PCI compared against percutaneous coronary intervention (PCI) with no intravascular imaging or PCI with intravascular ultrasound. (nice.org.uk)
  • We report on a dual-modality optical coherence tomography (OCT) ultrasound (US) system for intravascular imaging. (spiedigitallibrary.org)
  • It is a laser light equivalent of ultrasound imaging, measuring the intensity of backscattered infrared light rather than sound waves, and translates these optical echoes into a high-resolution, two-dimensional tomographic image. (apollohospitals.com)
  • Optical coherence tomography (OCT) is an intracoronary imaging modality with resolution 10 times higher than that of intravascular ultrasound (IVUS). (bmj.com)
  • Optical coherence tomography is an intravascular imaging modality akin to intravascular ultrasound. (clinicaladvisor.com)
  • According to physicians interviewed by MRG, the adopters of optical coherence tomography are likely to be those who have already embraced intravascular ultrasound technology. (thefreedictionary.com)
  • Evaluation of optical coherence tomography patterns in diabetic macular oedema. (thefreelibrary.com)
  • Further developed in 1990 by Naohiro Tanno, then a professor at Yamagata University it was referred to as heterodyne reflectance tomography, and in particular since 1991 by Huang et al. (wikipedia.org)
  • Optical coherence tomography (OCT) was developed by David Huang and colleagues at the Massachusetts Institute of Technology (MIT) [ 1 ]. (intechopen.com)
  • Spectral domain optical coherence tomography (SD-OCT) was a useful tool to study accommodation in human eye, but the maximum image depth is limited due to the decreased signal-to-noise ratio (SNR). (biomedcentral.com)
  • The aim of this study is to determine the condition to detect the status of a macular hole by spectral domain optical coherence tomography (SD-OCT) in gas-filled eyes. (clinicaltrials.gov)
  • We demonstrate a novel method for reducing saturation artifacts in spectral-domain optical coherence tomography (SD-OCT) systems. (mdpi.com)
  • This observational, retrospective cohort study was based on patients from the Doheny Eye Centers, Duke Eye Center, and Tufts Medical Center who received a bilateral spectral domain optical coherence tomography (SD-OCT) scan (one scan/eye) for clinical evaluation with available medical records. (dovepress.com)
  • The department has also acquired the latest generation Zeiss Spectral Domain High Definition Optical Coherence Tomography (OCT), the first installation of this machine in north India. (thefreedictionary.com)
  • Spectral-domain optical coherence tomography and adaptive optics may detect hydroxychloroquine retinal toxicity before symptomatic vision loss. (thefreedictionary.com)
  • The authors report a case of autosomal dominant cystoid macular dystrophy in which optical coherence tomography outlined the pathology and assisted in determining the etiology of the patient's macular edema. (healio.com)
  • Optical coherence tomography (OCT) is an imaging modality that provides a micron-level look at the tissues being examined. (medgadget.com)
  • Once limited to research and use by eye specialists, optical coherence tomography (OCT) is emerging as a major imaging modality. (diagnosticimaging.com)
  • A displacement image can be reconstructed, which enables a new modality of phase-sensitive OCT, called thermo-elastic OCT. An analysis of the results shows that the optical absorption is a dominating factor for the displacement. (tudelft.nl)
  • Optical coherence tomography has become established as an imaging modality in clinical ophthalmology and is finding applications in even gastrointestinal and dermatological arenas. (clinicaladvisor.com)
  • Optical coherence tomography enables high-resolution 3D imaging of retinal layers in the human eye. (mdpi.com)
  • Optical coherence tomography: advanced technology for the endoscopic imaging of Barrett's esophagus," Endoscopy , vol. 32, no. 12, pp. 921-930, 2000. (hindawi.com)
  • G&H has developed a fully integrated, fiber coupled, acousto-optic product that is ideal for applications such as laser doppler velocimetry and optical coherence tomography. (photonicsonline.com)
  • Optical coherence tomography of retinal and choroidal tumors. (biomedsearch.com)
  • Optical coherence tomography (OCT) has been introduced for more than 20 years and clinical applications using this technique greatly improve our ability in clinical diagnosis and research. (biomedcentral.com)
  • Diagnostic accuracy of optical coherence tomography for the diagnosis of bladder cancer: A systematic review and meta-analysis. (bioportfolio.com)
  • Optical coherence tomography (OCT) is a near infrared medical imaging technology allowing microscopic examination of body tissues for diagnosis of disease, especially retinal disease with imaging performed through the front of the eye, but also useful for imaging the skin and other epithelial tissues. (montana.edu)
  • Through its proprietary optical frequency domain imaging (OFDI), a next-generation frequency domain optical coherence tomography , NinePoint intends to bridge the gap between the diagnosis and treatment of disease. (thefreedictionary.com)
  • While OCT has become widely used for ophthalmic diagnosis and is gaining traction in cardiovascular imaging, the technique still relies on relatively expensive and bulky combinations of laser, optical and electronic equipment. (optics.org)
  • As the first text completely devoted to this topic, Anterior Segment Optical Coherence Tomography comprehensively explains both the scientific principles and the clinical applications of this exciting and advancing technology. (indigo.ca)
  • Optical Coherence Tomography in Multiple Sclerosis: Clinical Applications is aimed at clinical neurologists working with patients suffering from MS and general neurologists who see patients with visual symptoms in their daily practice. (ebooks.com)
  • This advance has required the development of new lasers, improved spectrometers, minimally invasive catheters and endoscopes, and novel optical and signal processing strategies. (nih.gov)
  • In this article we tested the novel optical coherence tomography (OCT) technique for noninvasive blood glucose monitoring in pilot clinical studies on healthy volunteers. (diabetesjournals.org)
  • Optical coherence tomography (OCT) has revolutionized the field of ophthalmology since its introduction 20 years ago. (biomedsearch.com)
  • Optical Coherence Tomography (OCT) is a relatively new imaging technique in ophthalmology. (bioportfolio.com)
  • Optical coherence tomography (OCT) is an intra-coronary diagnostic technique that provides detailed imagings of blood vessels in the current cardiac catheterization laboratory. (springer.com)
  • Optical coherence tomography diagnostic signs in posterior uveitis. (bioportfolio.com)
  • To compare the diagnostic ability of ultrasonography (US) and optical coherence tomography (OCT) in evaluating posterior vitreous detachment (PVD) status. (bioportfolio.com)
  • Optical coherence tomography (OCT) is a medical diagnostic tool, providing non-invasive, non-radiative and high resolution imaging. (bioportfolio.com)
  • Optical coherence tomography (OCT) is a noninvasive, diagnostic technique for accurately identifying and quantitatively characterizing macular holes. (intechopen.com)
  • In this report, the Global Optical Coherence Tomography Equipments Market is valued at USD XX million in 2016 and is expected to reach USD XX million by the end of 2022, growing at a CAGR of XX% between 2016 and 2022. (mynewsdesk.com)
  • Optical coherence tomography (OCT) is a non-invasive technique that enables a quantitative study of the changes that the optic nerve and the macula undergo in several neurodegenerative diseases. (frontiersin.org)
  • Methods, materials and measurement techniques "Largely unchanged for centuries, optical. (photonics.com)
  • The development of OCT in the early 1990s greatly benefited from components and methods used in fiber optical communications," said Fujimoto. (eurekalert.org)
  • Depending on the properties of the light source (superluminescent diodes, ultrashort pulsed lasers, and supercontinuum lasers have been employed), optical coherence tomography has achieved sub-micrometer resolution (with very wide-spectrum sources emitting over a ~100 nm wavelength range). (wikipedia.org)
  • Association of retinal nerve fibre layer thickness measured by confocal scanning laser ophthalmoscopy and optical coherence tomography with disc size and axial length. (thefreedictionary.com)
  • A two-dimensional optical coherence tomography technique has been developed in order to obtain multiple longitudinal slices of a biological sample directly, in a single Z-scan. (spie.org)
  • Optical coherence tomography (OCT) is an emerging biomedical imaging technology that enables micronâ€'scale, crossâ€'sectional, and three-dimensional (3D) imaging of biological tissues non-invasively. (nsti.org)
  • as director of product management and marketing to develop and commercialize the next generation of the firm s optical coherence tomography (OCT) spectrometers and systems. (thefreedictionary.com)
  • citation needed][verification needed] Optical coherence tomography is one of a class of optical tomographic techniques. (wikipedia.org)
  • The evidence on the safety of optical coherence tomography (OCT) to guide percutaneous coronary intervention (PCI) shows no major concerns. (nice.org.uk)
  • National Institute for Health and Care Excellence (NICE) has issued full guidance to the NHS in England, Wales, Scotland and Northern Ireland on Optical Coherence Tomography to guide percutaneous coronary intervention, in February 2014. (nice.org.uk)
  • To assess the tolerability of performing optical coherence tomography and/or optical spectroscopy in patients with acute oral mucositis. (bioportfolio.com)
  • 3. Hassenstein A, Bialasiewicz AA, Richard G. Optical coherence tomography in uveitis patients . (medsci.org)
  • Evaluation of posterior vitreous detachment using ultrasonography and optical coherence tomography. (bioportfolio.com)
  • Optical coherence tomography (OCT) is capable of evaluating all the important optical properties of a film or film stack, including topology of surfaces or layer-to-layer interfaces, the refractive index and thickness, and polarization property. (intechopen.com)
  • The aim of this study was to evaluate retinal thickness in eight diabetic dogs, four females and four males of different breeds and ages ranging from 6 to 15 years, by optical coherence tomography (OCT) and to compare them with non-diabetic dogs. (scielo.br)
  • Use of optical coherence tomography to assess variations in macular retinal thickness in myopia. (thefreedictionary.com)
  • Schumann, H. Enhanced Grid-Based Visual Analysis of Retinal Layer Thickness with Optical Coherence Tomography. (mdpi.com)
  • Röhlig M, Prakasam RK, Stüwe J, Schmidt C, Stachs O, Schumann H. Enhanced Grid-Based Visual Analysis of Retinal Layer Thickness with Optical Coherence Tomography. (mdpi.com)
  • In recent years, the application of optical coherence tomography has expanded toward material characterization. (intechopen.com)
  • Characterization of the human myocardium by optical coherence tomography. (bioportfolio.com)
  • Massachusetts General Hospital reports positive results in a study using optical coherence tomography (OCT) to identify the characteristics of coronary arterial plaques in patients with various cardiac symptoms. (medgadget.com)
  • Skin simulating phantoms with different optical properties can be used to optimise a system before it can be used on patients. (csir.co.za)
  • OBJECTIVE -To study the feasibility of noninvasive blood glucose monitoring using optical coherence tomography (OCT) technique in healthy volunteers. (diabetesjournals.org)
  • The feasibility of using Optical Coherence Tomography (OCT) for oxygenation determination of whole blood was investigated on porcine blood samples. (spie.org)
  • With all OCT approaches, axial sectioning is linked to the coherence length of the light source. (laserfocusworld.com)

No images available that match "tomography optical coherence"