The turning inward of the lines of sight toward each other.
Disorders that feature impairment of eye movements as a primary manifestation of disease. These conditions may be divided into infranuclear, nuclear, and supranuclear disorders. Diseases of the eye muscles or oculomotor cranial nerves (III, IV, and VI) are considered infranuclear. Nuclear disorders are caused by disease of the oculomotor, trochlear, or abducens nuclei in the BRAIN STEM. Supranuclear disorders are produced by dysfunction of higher order sensory and motor systems that control eye movements, including neural networks in the CEREBRAL CORTEX; BASAL GANGLIA; CEREBELLUM; and BRAIN STEM. Ocular torticollis refers to a head tilt that is caused by an ocular misalignment. Opsoclonus refers to rapid, conjugate oscillations of the eyes in multiple directions, which may occur as a parainfectious or paraneoplastic condition (e.g., OPSOCLONUS-MYOCLONUS SYNDROME). (Adams et al., Principles of Neurology, 6th ed, p240)
A condition in which the intraocular pressure is elevated above normal and which may lead to glaucoma.
The organ of sight constituting a pair of globular organs made up of a three-layered roughly spherical structure specialized for receiving and responding to light.
The study and treatment of defects in binocular vision resulting from defects in the optic musculature or of faulty visual habits. It involves a technique of eye exercises designed to correct the visual axes of eyes not properly coordinated for binocular vision.
Infection caused by the protozoan parasite TOXOPLASMA in which there is extensive connective tissue proliferation, the retina surrounding the lesions remains normal, and the ocular media remain clear. Chorioretinitis may be associated with all forms of toxoplasmosis, but is usually a late sequel of congenital toxoplasmosis. The severe ocular lesions in infants may lead to blindness.
The dioptric adjustment of the EYE (to attain maximal sharpness of retinal imagery for an object of regard) referring to the ability, to the mechanism, or to the process. Ocular accommodation is the effecting of refractive changes by changes in the shape of the CRYSTALLINE LENS. Loosely, it refers to ocular adjustments for VISION, OCULAR at various distances. (Cline et al., Dictionary of Visual Science, 4th ed)
The blending of separate images seen by each eye into one composite image.
Albinism affecting the eye in which pigment of the hair and skin is normal or only slightly diluted. The classic type is X-linked (Nettleship-Falls), but an autosomal recessive form also exists. Ocular abnormalities may include reduced pigmentation of the iris, nystagmus, photophobia, strabismus, and decreased visual acuity.
The functional superiority and preferential use of one eye over the other. The term is usually applied to superiority in sighting (VISUAL PERCEPTION) or motor task but not difference in VISUAL ACUITY or dysfunction of one of the eyes. Ocular dominance can be modified by visual input and NEUROTROPHIC FACTORS.
Refraction of LIGHT effected by the media of the EYE.
Measurement of ocular tension (INTRAOCULAR PRESSURE) with a tonometer. (Cline, et al., Dictionary of Visual Science, 4th ed)
Processes and properties of the EYE as a whole or of any of its parts.
Tumors or cancer of the EYE.
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)
Damage or trauma inflicted to the eye by external means. The concept includes both surface injuries and intraocular injuries.
Misalignment of the visual axes of the eyes. In comitant strabismus the degree of ocular misalignment does not vary with the direction of gaze. In noncomitant strabismus the degree of misalignment varies depending on direction of gaze or which eye is fixating on the target. (Miller, Walsh & Hoyt's Clinical Neuro-Ophthalmology, 4th ed, p641)
The pressure of the fluids in the eye.
Tuberculous infection of the eye, primarily the iris, ciliary body, and choroid.
The fluid secreted by the lacrimal glands. This fluid moistens the CONJUNCTIVA and CORNEA.
Voluntary or reflex-controlled movements of the eye.
The muscles that move the eye. Included in this group are the medial rectus, lateral rectus, superior rectus, inferior rectus, inferior oblique, superior oblique, musculus orbitalis, and levator palpebrae superioris.
Sterile solutions that are intended for instillation into the eye. It does not include solutions for cleaning eyeglasses or CONTACT LENS SOLUTIONS.
The positioning and accommodation of eyes that allows the image to be brought into place on the FOVEA CENTRALIS of each eye.
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.
Mild to severe infections of the eye and its adjacent structures (adnexa) by adult or larval protozoan or metazoan parasites.
A form of ocular misalignment where the visual axes diverge inappropriately. For example, medial rectus muscle weakness may produce this condition as the affected eye will deviate laterally upon attempted forward gaze. An exotropia occurs due to the relatively unopposed force exerted on the eye by the lateral rectus muscle, which pulls the eye in an outward direction.
Infection, moderate to severe, caused by bacteria, fungi, or viruses, which occurs either on the external surface of the eye or intraocularly with probable inflammation, visual impairment, or blindness.
A process of complicated morphogenetic cell movements that reorganizes a bilayer embryo into one with three GERM LAYERS and specific orientation (dorsal/ventral; anterior/posterior). Gastrulation describes the germ layer development of a non-mammalian BLASTULA or that of a mammalian BLASTOCYST.
Inflammation of part or all of the uvea, the middle (vascular) tunic of the eye, and commonly involving the other tunics (sclera and cornea, and the retina). (Dorland, 27th ed)
Corneal and conjunctival dryness due to deficient tear production, predominantly in menopausal and post-menopausal women. Filamentary keratitis or erosion of the conjunctival and corneal epithelium may be caused by these disorders. Sensation of the presence of a foreign body in the eye and burning of the eyes may occur.
The process in which light signals are transformed by the PHOTORECEPTOR CELLS into electrical signals which can then be transmitted to the brain.
Abnormally low intraocular pressure often related to chronic inflammation (uveitis).
A form of ocular misalignment characterized by an excessive convergence of the visual axes, resulting in a "cross-eye" appearance. An example of this condition occurs when paralysis of the lateral rectus muscle causes an abnormal inward deviation of one eye on attempted gaze.
Deviations from the average or standard indices of refraction of the eye through its dioptric or refractive apparatus.
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.
Diseases of the cornea.
The clear, watery fluid which fills the anterior and posterior chambers of the eye. It has a refractive index lower than the crystalline lens, which it surrounds, and is involved in the metabolism of the cornea and the crystalline lens. (Cline et al., Dictionary of Visual Science, 4th ed, p319)
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.
Congenital absence of or defects in structures of the eye; may also be hereditary.
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.
A ring of tissue extending from the scleral spur to the ora serrata of the RETINA. It consists of the uveal portion and the epithelial portion. The ciliary muscle is in the uveal portion and the ciliary processes are in the epithelial portion.
The front third of the eyeball that includes the structures between the front surface of the cornea and the front of the VITREOUS BODY.
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)
The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)
A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task.
The thin, highly vascular membrane covering most of the posterior of the eye between the RETINA and SCLERA.
A pair of ophthalmic lenses in a frame or mounting which is supported by the nose and ears. The purpose is to aid or improve vision. It does not include goggles or nonprescription sun glasses for which EYE PROTECTIVE DEVICES is available.
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)
Application of pharmaceutically active agents on the tissues of the EYE.
Particles of any solid substance, generally under 30 microns in size, often noted as PM30. There is special concern with PM1 which can get down to PULMONARY ALVEOLI and induce MACROPHAGE ACTIVATION and PHAGOCYTOSIS leading to FOREIGN BODY REACTION and LUNG DISEASES.
The relationships of groups of organisms as reflected by their genetic makeup.
Infections in the inner or external eye caused by microorganisms belonging to several families of bacteria. Some of the more common genera found are Haemophilus, Neisseria, Staphylococcus, Streptococcus, and Chlamydia.
Filarial infection of the eyes transmitted from person to person by bites of Onchocerca volvulus-infected black flies. The microfilariae of Onchocerca are thus deposited beneath the skin. They migrate through various tissues including the eye. Those persons infected have impaired vision and up to 20% are blind. The incidence of eye lesions has been reported to be as high as 30% in Central America and parts of Africa.
A chronic blistering disease with predilection for mucous membranes and less frequently the skin, and with a tendency to scarring. It is sometimes called ocular pemphigoid because of conjunctival mucous membrane involvement.
Involuntary movements of the eye that are divided into two types, jerk and pendular. Jerk nystagmus has a slow phase in one direction followed by a corrective fast phase in the opposite direction, and is usually caused by central or peripheral vestibular dysfunction. Pendular nystagmus features oscillations that are of equal velocity in both directions and this condition is often associated with visual loss early in life. (Adams et al., Principles of Neurology, 6th ed, p272)
Images seen by one eye.
Stratified squamous epithelium that covers the outer surface of the CORNEA. It is smooth and contains many free nerve endings.
A transparent, biconvex structure of the EYE, enclosed in a capsule and situated behind the IRIS and in front of the vitreous humor (VITREOUS BODY). It is slightly overlapped at its margin by the ciliary processes. Adaptation by the CILIARY BODY is crucial for OCULAR ACCOMMODATION.
The difference between two images on the retina when looking at a visual stimulus. This occurs since the two retinas do not have the same view of the stimulus because of the location of our eyes. Thus the left eye does not get exactly the same view as the right eye.
Each of the upper and lower folds of SKIN which cover the EYE when closed.
The aperture in the iris through which light passes.
Inflammation of the choroid in which the sensory retina becomes edematous and opaque. The inflammatory cells and exudate may burst through the sensory retina to cloud the vitreous body.
The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.
The act of knowing or the recognition of a distance by recollective thought, or by means of a sensory process which is under the influence of set and of prior experience.
The developmental stage that follows BLASTULA or BLASTOCYST. It is characterized by the morphogenetic cell movements including invagination, ingression, and involution. Gastrulation begins with the formation of the PRIMITIVE STREAK, and ends with the formation of three GERM LAYERS, the body plan of the mature organism.
The application of drug preparations to the surfaces of the body, especially the skin (ADMINISTRATION, CUTANEOUS) or mucous membranes. This method of treatment is used to avoid systemic side effects when high doses are required at a localized area or as an alternative systemic administration route, to avoid hepatic processing for example.
Inflammation of the cornea.
Neural tracts connecting one part of the nervous system with another.
The selected form given to a natural tooth when it is reduced by instrumentation to receive a prosthesis (e.g., artificial crown or a retainer for a fixed or removable prosthesis). The selection of the form is guided by clinical circumstances and physical properties of the materials that make up the prosthesis. (Boucher's Clinical Dental Terminology, 4th ed, p239)
An order of fish comprising salmons, trouts, whitefish, graylings, and other families. They are both marine and freshwater fish, found in all oceans and are quite numerous in the Northern Hemisphere. (From Nelson: Fishes of the World)
Nerve structures through which impulses are conducted from a peripheral part toward a nerve center.
Paralysis of one or more of the ocular muscles due to disorders of the eye muscles, neuromuscular junction, supporting soft tissue, tendons, or innervation to the muscles.
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).
The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.
Glaucoma in which the angle of the anterior chamber is open and the trabecular meshwork does not encroach on the base of the iris.
An abrupt voluntary shift in ocular fixation from one point to another, as occurs in reading.
Infections of the eye caused by minute intracellular agents. These infections may lead to severe inflammation in various parts of the eye - conjunctiva, iris, eyelids, etc. Several viruses have been identified as the causative agents. Among these are Herpesvirus, Adenovirus, Poxvirus, and Myxovirus.
Computer-based representation of physical systems and phenomena such as chemical processes.
Inflammation of the eyelids.
A gelatinous membrane overlying the acoustic maculae of SACCULE AND UTRICLE. It contains minute crystalline particles (otoliths) of CALCIUM CARBONATE and protein on its outer surface. In response to head movement, the otoliths shift causing distortion of the vestibular hair cells which transduce nerve signals to the BRAIN for interpretation of equilibrium.
Bony cavity that holds the eyeball and its associated tissues and appendages.
Elements of limited time intervals, contributing to particular results or situations.
An exotic species of the family CYPRINIDAE, originally from Asia, that has been introduced in North America. They are used in embryological studies and to study the effects of certain chemicals on development.
An abnormal twisting or rotation of a bodily part or member on its axis.
Investigative technique commonly used during ELECTROENCEPHALOGRAPHY in which a series of bright light flashes or visual patterns are used to elicit brain activity.
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.
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
Refers to any inflammation of the sclera including episcleritis, a benign condition affecting only the episclera, which is generally short-lived and easily treated. Classic scleritis, on the other hand, affects deeper tissue and is characterized by higher rates of visual acuity loss and even mortality, particularly in necrotizing form. Its characteristic symptom is severe and general head pain. Scleritis has also been associated with systemic collagen disease. Etiology is unknown but is thought to involve a local immune response. Treatment is difficult and includes administration of anti-inflammatory and immunosuppressive agents such as corticosteroids. Inflammation of the sclera may also be secondary to inflammation of adjacent tissues, such as the conjunctiva.
A series of tests used to assess various functions of the eyes.
A beta-adrenergic antagonist similar in action to PROPRANOLOL. The levo-isomer is the more active. Timolol has been proposed as an antihypertensive, antiarrhythmic, antiangina, and antiglaucoma agent. It is also used in the treatment of MIGRAINE DISORDERS and tremor.
Neurons which conduct NERVE IMPULSES to the CENTRAL NERVOUS SYSTEM.
A visual symptom in which a single object is perceived by the visual cortex as two objects rather than one. Disorders associated with this condition include REFRACTIVE ERRORS; STRABISMUS; OCULOMOTOR NERVE DISEASES; TROCHLEAR NERVE DISEASES; ABDUCENS NERVE DISEASES; and diseases of the BRAIN STEM and OCCIPITAL LOBE.
A superficial, epithelial Herpesvirus hominis infection of the cornea, characterized by the presence of small vesicles which may break down and coalesce to form dendritic ulcers (KERATITIS, DENDRITIC). (Dictionary of Visual Science, 3d ed)
Surgery performed on the eye or any of its parts.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Echocardiography applying the Doppler effect, with the superposition of flow information as colors on a gray scale in a real-time image.
Proteins obtained from the ZEBRAFISH. Many of the proteins in this species have been the subject of studies involving basic embryological development (EMBRYOLOGY).
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)
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
A surgical specialty concerned with the structure and function of the eye and the medical and surgical treatment of its defects and diseases.
Analogs or derivatives of prostaglandins F that do not occur naturally in the body. They do not include the product of the chemical synthesis of hormonal PGF.
Congenital anomaly in which some of the structures of the eye are absent due to incomplete fusion of the fetal intraocular fissure during gestation.
The process of cumulative change at the level of DNA; RNA; and PROTEINS, over successive generations.
Theoretical representations that simulate the behavior or activity of the neurological system, processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.
Tumors or cancer of the CONJUNCTIVA.
Set of cell bodies and nerve fibers conducting impulses from the eyes to the cerebral cortex. It includes the RETINA; OPTIC NERVE; optic tract; and geniculocalcarine tract.
An oval, bony chamber of the inner ear, part of the bony labyrinth. It is continuous with bony COCHLEA anteriorly, and SEMICIRCULAR CANALS posteriorly. The vestibule contains two communicating sacs (utricle and saccule) of the balancing apparatus. The oval window on its lateral wall is occupied by the base of the STAPES of the MIDDLE EAR.
The lectin wheatgerm agglutinin conjugated to the enzyme HORSERADISH PEROXIDASE. It is widely used for tracing neural pathways.
Partial or complete opacity on or in the lens or capsule of one or both eyes, impairing vision or causing blindness. The many kinds of cataract are classified by their morphology (size, shape, location) or etiology (cause and time of occurrence). (Dorland, 27th ed)
Geological formations consisting of underground enclosures with access from the surface.
The total area or space visible in a person's peripheral vision with the eye looking straightforward.
The four cellular masses in the floor of the fourth ventricle giving rise to a widely dispersed special sensory system. Included is the superior, medial, inferior, and LATERAL VESTIBULAR NUCLEUS. (From Dorland, 27th ed)
The pigmented vascular coat of the eyeball, consisting of the CHOROID; CILIARY BODY; and IRIS, which are continuous with each other. (Cline et al., Dictionary of Visual Science, 4th ed)
Injury to any part of the eye by extreme heat, chemical agents, or ultraviolet radiation.
The tear-forming and tear-conducting system which includes the lacrimal glands, eyelid margins, conjunctival sac, and the tear drainage system.
The 3d cranial nerve. The oculomotor nerve sends motor fibers to the levator muscles of the eyelid and to the superior rectus, inferior rectus, and inferior oblique muscles of the eye. It also sends parasympathetic efferents (via the ciliary ganglion) to the muscles controlling pupillary constriction and accommodation. The motor fibers originate in the oculomotor nuclei of the midbrain.
Involuntary rhythmical movements of the eyes in the normal person. These can be naturally occurring as in end-position (end-point, end-stage, or deviational) nystagmus or induced by the optokinetic drum (NYSTAGMUS, OPTOKINETIC), caloric test, or a rotating chair.
A form of herpetic keratitis characterized by the formation of small vesicles which break down and coalesce to form recurring dendritic ulcers, characteristically irregular, linear, branching, and ending in knoblike extremities. (Dictionary of Visual Science, 3d ed)
Inflammation of the iris characterized by circumcorneal injection, aqueous flare, keratotic precipitates, and constricted and sluggish pupil along with discoloration of the iris.
Area of the OCCIPITAL LOBE concerned with the processing of visual information relayed via VISUAL PATHWAYS.
Inflammation of the anterior uvea comprising the iris, angle structures, and the ciliary body. Manifestations of this disorder include ciliary injection, exudation into the anterior chamber, iris changes, and adhesions between the iris and lens (posterior synechiae). Intraocular pressure may be increased or reduced.
A species of the genus MACACA which typically lives near the coast in tidal creeks and mangrove swamps primarily on the islands of the Malay peninsula.
Simultaneous inflammation of the cornea and conjunctiva.
Infection by a variety of fungi, usually through four possible mechanisms: superficial infection producing conjunctivitis, keratitis, or lacrimal obstruction; extension of infection from neighboring structures - skin, paranasal sinuses, nasopharynx; direct introduction during surgery or accidental penetrating trauma; or via the blood or lymphatic routes in patients with underlying mycoses.
The absence or restriction of the usual external sensory stimuli to which the individual responds.
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.
Imaging techniques used to colocalize sites of brain functions or physiological activity with brain structures.
Congenital or developmental anomaly in which the eyeballs are abnormally small.
Disorder occurring in the central or peripheral area of the cornea. The usual degree of transparency becomes relatively opaque.
Inanimate objects that become enclosed in the eye.
Artery originating from the internal carotid artery and distributing to the eye, orbit and adjacent facial structures.
Substances added to pharmaceutical preparations to protect them from chemical change or microbial action. They include ANTI-BACTERIAL AGENTS and antioxidants.
The blood vessels which supply and drain the RETINA.
Voluntary or involuntary motion of head that may be relative to or independent of body; includes animals and humans.
The sedge plant family of the order Cyperales, subclass Commelinidae, class Liliopsida (monocotyledons)
A species of the genus MACACA inhabiting India, China, and other parts of Asia. The species is used extensively in biomedical research and adapts very well to living with humans.
Pieces of glass or other transparent materials used for magnification or increased visual acuity.
The part of the brain that connects the CEREBRAL HEMISPHERES with the SPINAL CORD. It consists of the MESENCEPHALON; PONS; and MEDULLA OBLONGATA.
Conjunctivitis due to hypersensitivity to various allergens.
The adjustment of the eye to variations in the intensity of light. Light adaptation is the adjustment of the eye when the light threshold is increased; DARK ADAPTATION when the light is greatly reduced. (From Cline et al., Dictionary of Visual Science, 4th ed)
The surgical removal of the eyeball leaving the eye muscles and remaining orbital contents intact.
Inflammation, often mild, of the conjunctiva caused by a variety of viral agents. Conjunctival involvement may be part of a systemic infection.
A chronic infection of the CONJUNCTIVA and CORNEA caused by CHLAMYDIA TRACHOMATIS.
The developmental entity of a fertilized egg (ZYGOTE) in animal species other than MAMMALS. For chickens, use CHICK EMBRYO.
Methods and procedures for the diagnosis of diseases of the eye or of vision disorders.
Inflammation of the choroid.
A reflex wherein impulses are conveyed from the cupulas of the SEMICIRCULAR CANALS and from the OTOLITHIC MEMBRANE of the SACCULE AND UTRICLE via the VESTIBULAR NUCLEI of the BRAIN STEM and the median longitudinal fasciculus to the OCULOMOTOR NERVE nuclei. It functions to maintain a stable retinal image during head rotation by generating appropriate compensatory EYE MOVEMENTS.
Motion of an object in which either one or more points on a line are fixed. It is also the motion of a particle about a fixed point. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
The inability to see or the loss or absence of perception of visual stimuli. This condition may be the result of EYE DISEASES; OPTIC NERVE DISEASES; OPTIC CHIASM diseases; or BRAIN DISEASES affecting the VISUAL PATHWAYS or OCCIPITAL LOBE.
Method of making images on a sensitized surface by exposure to light or other radiant energy.
Behavioral manifestations of cerebral dominance in which there is preferential use and superior functioning of either the left or the right side, as in the preferred use of the right hand or right foot.
The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.
Use of electric potential or currents to elicit biological responses.
Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.
The time from the onset of a stimulus until a response is observed.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.
The 6th cranial nerve which originates in the ABDUCENS NUCLEUS of the PONS and sends motor fibers to the lateral rectus muscles of the EYE. Damage to the nerve or its nucleus disrupts horizontal eye movement control.
Theoretical representations that simulate the behavior or activity of genetic processes or phenomena. They include the use of mathematical equations, computers, and other electronic equipment.
Inflammation of the RETINA. It is rarely limited to the retina, but is commonly associated with diseases of the choroid (CHORIORETINITIS) and of the OPTIC DISK (neuroretinitis).
Acetanilide derivative used as a local anesthetic.
Central retinal artery and its branches. It arises from the ophthalmic artery, pierces the optic nerve and runs through its center, enters the eye through the porus opticus and branches to supply the retina.
Remains, impressions, or traces of animals or plants of past geological times which have been preserved in the earth's crust.
Computer-assisted study of methods for obtaining useful quantitative solutions to problems that have been expressed mathematically.
A refractive error in which rays of light entering the eye parallel to the optic axis are brought to a focus behind the retina, as a result of the eyeball being too short from front to back. It is also called farsightedness because the near point is more distant than it is in emmetropia with an equal amplitude of accommodation. (Dorland, 27th ed)
A genus of the subfamily CERCOPITHECINAE, family CERCOPITHECIDAE, consisting of 16 species inhabiting forests of Africa, Asia, and the islands of Borneo, Philippines, and Celebes.
Act of eliciting a response from a person or organism through physical contact.
An annular transitional zone, approximately 1 mm wide, between the cornea and the bulbar conjunctiva and sclera. It is highly vascular and is involved in the metabolism of the cornea. It is ophthalmologically significant in that it appears on the outer surface of the eyeball as a slight furrow, marking the line between the clear cornea and the sclera. (Dictionary of Visual Science, 3d ed)
In statistics, a technique for numerically approximating the solution of a mathematical problem by studying the distribution of some random variable, often generated by a computer. The name alludes to the randomness characteristic of the games of chance played at the gambling casinos in Monte Carlo. (From Random House Unabridged Dictionary, 2d ed, 1993)
The use of statistical and mathematical methods to analyze biological observations and phenomena.
Set of nerve fibers conducting impulses from olfactory receptors to the cerebral cortex. It includes the OLFACTORY NERVE; OLFACTORY BULB; OLFACTORY TRACT; OLFACTORY TUBERCLE; ANTERIOR PERFORATED SUBSTANCE; and OLFACTORY CORTEX.
A ready-made or custom-made prosthesis of glass or plastic shaped and colored to resemble the anterior portion of a normal eye and used for cosmetic reasons. It is attached to the anterior portion of an orbital implant (ORBITAL IMPLANTS) which is placed in the socket of an enucleated or eviscerated eye. (From Dorland, 28th ed)
Part of the DIENCEPHALON inferior to the caudal end of the dorsal THALAMUS. Includes the lateral geniculate body which relays visual impulses from the OPTIC TRACT to the calcarine cortex, and the medial geniculate body which relays auditory impulses from the lateral lemniscus to the AUDITORY CORTEX.
Recording of the average amplitude of the resting potential arising between the cornea and the retina in light and dark adaptation as the eyes turn a standard distance to the right and the left. The increase in potential with light adaptation is used to evaluate the condition of the retinal pigment epithelium.
Inflammation in which both the anterior and posterior segments of the uvea are involved and a specific focus is not apparent. It is often severe and extensive and a serious threat to vision. Causes include systemic diseases such as tuberculosis, sarcoidosis, and syphilis, as well as malignancies. The intermediate segment of the eye is not involved.
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.
Large herbivorous tropical American lizards.
Substances used to identify the location and to characterize the types of NEURAL PATHWAYS.
Recording of nystagmus based on changes in the electrical field surrounding the eye produced by the difference in potential between the cornea and the retina.
The movement of cells from one location to another. Distinguish from CYTOKINESIS which is the process of dividing the CYTOPLASM of a cell.
NEURAL PATHWAYS and connections within the CENTRAL NERVOUS SYSTEM, beginning at the hair cells of the ORGAN OF CORTI, continuing along the eighth cranial nerve, and terminating at the AUDITORY CORTEX.
Theoretical representations that simulate the behavior or activity of systems, processes, or phenomena. They include the use of mathematical equations, computers, and other electronic equipment.
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.
Cellular receptors which mediate the sense of temperature. Thermoreceptors in vertebrates are mostly located under the skin. In mammals there are separate types of thermoreceptors for cold and for warmth and NOCICEPTORS which detect cold or heat extreme enough to cause pain.
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.
Ocular disorders attendant upon non-ocular disease or injury.
Personal devices for protection of the eyes from impact, flying objects, glare, liquids, or injurious radiation.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
Loss of epithelial tissue from the surface of the cornea due to progressive erosion and necrosis of the tissue; usually caused by bacterial, fungal, or viral infection.
The study of systems which respond disproportionately (nonlinearly) to initial conditions or perturbing stimuli. Nonlinear systems may exhibit "chaos" which is classically characterized as sensitive dependence on initial conditions. Chaotic systems, while distinguished from more ordered periodic systems, are not random. When their behavior over time is appropriately displayed (in "phase space"), constraints are evident which are described by "strange attractors". Phase space representations of chaotic systems, or strange attractors, usually reveal fractal (FRACTALS) self-similarity across time scales. Natural, including biological, systems often display nonlinear dynamics and chaos.
Awareness of oneself in relation to time, place and person.
Lenses designed to be worn on the front surface of the eyeball. (UMDNS, 1999)
The layer of pigment-containing epithelial cells in the RETINA; the CILIARY BODY; and the IRIS in the eye.
The selecting and organizing of visual stimuli based on the individual's past experience.