AberrationDistortions, related to astigmatism , that reason the inability of irradiate rays entering the eye to converge (come together) come a single focus allude on the retina . Aberration are divided into two main categories: higher-order and lower-order.AblationSurgical removed of tissue, generally using a cool beam laserAblation zoneThe area of organization that is removed throughout laser surgeryAccommodationAbility that the eye to readjust its focus in between distant objects and near objects.Altitudinal visual ar defectsThis term explains a visual ar defect in which either the upper or lower half of the visual field is selectively affected. The selective abnormality regularly creates a horizontal line throughout the visual ar (known together "respecting the horizontal meridian"). Altitudinal defects happen in retinal vascular disease, glaucoma, and other obstacle that affect the eye itself.AmblyopiaDullness or obscurity of sight for no noticeable organic reason, therefore not correctable through glasses or surgery. Sometimes referred to as a lazy eye, within one eye becomes dependent ~ above the various other eye come focus, usually emerged in early childhood. Often associated with strabismus. The problems that most commonly cause amblyopia space eye misalignment (strabismus), a significant difference in spectacle prescription (refractive error) between the 2 eyes (anisometropia), or discontinuity of the light course of among the eyes (by cataract, scar, tumor, etc.). If amblyopia is no treated before the age of 8, the intuitive deficit is normally permanent.
You are watching: Visual examination of the eye medical term
Amsler gridHand held chart featuring horizontal and also vertical lines, usually white on black background, used to check for central visual ar defects.Angle (Drainage Angle)Drainage area of the eye formed in between the cornea and also the iris , named for that is angular shape, which is why friend see the word "angle" in the various glaucoma names.AnisometropiaCondition that the eyes in i beg your pardon they have actually unequal refractive power.Anterior ChamberSpace in between the cornea and also the crystalline lens , which has aqueous feeling .Anterior ocular segmentPart the the eye anterior come the crystalline lens , consisting of the cornea , anterior room , iris and ciliary body .AntioxidantsMicronutrients that destroy or neutralize free radicals, molecule that have actually been implicated together one causative aspect in the stimulation of abnormal to move reproduction (cancer) and cellular destruction (aging).Antireflective coatingCoating ~ above the front or earlier of glasses lenses, i m sorry minimizes the glare for patients who are extremely bothered by glare.AphakiaAbsence that the lens of the eye.Aqueous humorTransparent fluid occupying the anterior chamber and maintains eye pressure.Argon laserdevice used to act glaucoma (usually open angle) and diabetic retinopathy making use of a heat beam.ARMDAge related macular degeneration: Destruction and also loss of the photoreceptors in the macula an ar of the retina leading to decreased main vision and, in advanced cases, blindness.AsthenopiaEyestrainAstigmatic KeratotomyA modified kind of Radial Keratotomy (RK).AstigmatismStructural defects the the eye in i beg your pardon the light rays from a perceived object perform not fulfill in a single focal point, leading to blurred photos being sent out to the brain. One astigmatic cornea is not perfectly rounded prefer a basketball yet has an rarely often rare shape more like the side of a football. Astigmatism is most often combined with myopia or hyperopia .Autosomal recessiveAn inheritance sample in which a human must inherit two duplicates of one abnormal gene (one from every parent) in bespeak to construct the disease. If two individuals each lug one copy of one abnormal gene, then each son born come these two parents will have a 25% possibility of receiving 2 copies of the abnormal gene and also as a result, inherit the disease. Cystic fibrosis is an example of one autosomal recessive disease.Cecocentral scotomasThese room visual ar defects that extend from the central vision to the organic blind spot. This form of ar defect typically represents an insult to the cluster of retinal ganglion cells referred to as the papillomacular bundle.Color blindnessAlso recognized as Dyschromotopsia. A general term for shade vision abnormalities. Heritable dyschromatopsias include red (protan), eco-friendly (deutan), and blue (tritan) color vision deficits. These deficits may be partial (-omaly) or complete (-opia). Red and also green shade vision defects are X-linked while ns of the blue receptor (tritanopia) is inherited in an autosomal recessive fashion. Also see: ProtanomalousConjunctivochalasisA redundant folds in the conjunctiva typically located between the globe and also the lower eyelid. Loosened bulbar conjunctiva the may become pinched in between the lids and cause tearing and inflammation. Commonly age-related. Usually discovered along the reduced lid margin. The interferes with the normal circulation of tears causing dry eye and epiphora.Cupping (Disk cupping)An enlargement that the cup or central depression in the optic nerve head. Cupping is visible when viewing the ago of the eye with an ophthalmoscope. An enlarged cup particularly if add by a notch or a tiny spot the bleeding is a authorize of glaucoma. Cupping is a clinical sign that shows that a big number the nerve yarn in the optic nerve have actually been lost.Deuteranopia, deuteranopicComplete color deficiency influence the ability to watch the shade green. There are three possible color vision deficits: red (protan), environment-friendly (deutan), and blue (tritan). The suffixes –omaly and –opia show partial and also complete shade vision deficits, respectively. Therefore, a human who has deuteranopia has a complete green color deficit.DyschromotopsiaA basic term for shade vision abnormalities. Heritable dyschromatopsias include red (protan), green (deutan), and also blue (tritan) shade vision deficits. This deficits may be partial (-omaly) or complete (-opia). Red and also green shade vision defects are X-linked while lose of the blue receptor (tritanopia) is inherited in one autosomal recessive fashion.Electroretinogram (ERG)A check that steps the electrical activity of the retina when exposed to flashes of light of varying intensity. Abnormalities in the electroretinogram commonly occur in conditions that impact the photoreceptor cells (e.g. Retinitis pigmentosa).EpiphoraExcessive tear production or insufficient tear drainage native the eyes (usually native blockage the the lacrimal duct) causing overflow of tears onto the face.
FOVEA and FOVEOLA
FoveaIn the human eye the term fovea (or fovea centralis) is the "pit" in the retina that allows for best acuity that vision. The human being fovea has actually a diameter of around 1.0 mm with a high concentration of cone photoreceptors.FoveolaThe center of the fovea is the foveola – around 0.2 mm in diameter – where only
cone photoreceptors are present. The central fovea consists of really compact cones, diluent and much more rod-like in appearance than cones elsewhere. Starting at the outskirts of the fovea, however, rods slowly appear, and the absolute thickness of cone receptors progressively decreases.Glaucoma, normal-tensionGlaucoma in i beg your pardon the intraocular push is normal but there is progressive optic nerve damage and also visual field loss. Likewise known together Low stress and anxiety Glaucoma.
LOW stress GLAUCOMA
Goldmann intuitive fieldA kind of vision check in which progressively dimmer lights are relocated from the peripheral vision right into the main vision, making use of an tool that permits the allude at which the light is an initial seen to be accurately mapped. In this test, a trained perimetrist moves the stimulus; stimulus brightness is held constant. The limits of the visual field are mapped to lights of different sizes and brightness. Also known together Goldmann kinetic perimetry.Incomplete penetranceThe concept that even though numerous members the a household or populace may have the very same DNA mutation, no everyone with that mutation will have or develop the disease. This is in contrast to change expressivity which means that human being with the same disease have varying disease severity. Penetrance, in contrast, is more of a yes/no question – does or does not the person have actually the disease.Ishihara platesIsopterA heat connecting a series of point out in a visual field at i beg your pardon a human being is able to detect a details size and intensity of light. Isopters in normal visual fields are oval in shape.Leber hereditary optic neuropathy (LHON)A condition entity the most typically affects young men in their teens and early twenties and causes significantly decreased central vision in both eyes. The gene that cause LHON are brought on tiny circular mitochondrial DNA molecules that are inherited indigenous an people mother. This problem is very rare (affecting fewer 보다 1 every million human being per year) and does not impact everyone that harbors the genetic defect. The visual field defects in LHON are frequently cecocentral scotomas. There are three other eye conditions named ~ Theodore Leber: 1) Leber congenital amaurosis (blindness at birth) inherited in an autosomal recessive fashion, 2) Leber"s stellate neuroretinopathy (a non-heritable condition connected with cat scratch disease) and 3) Leber"s armed forces aneurysms (a non-heritable vascular malformation the the retina comparable to Coat"s disease).Macula, macula luteaThe main portion of the retina that is responsible for central vision. An insult to the macula can cause loss of central vision and also a significant decrease in intuitive acuity.Nagel anomaloscopeA an equipment that used to determine degree of red or green color vision deficit. A dial top top the anomaloscope is adjusted until the viewer (patient) believes that the green-red balance is suitable compared with a traditional yellow light whose soot can also be varied. As soon as a person with normal color vision views the "match" made by a patient through abnormal color vision, a deficit in one of two people red or green shade vision is conveniently apparent.
See more: Wolverine Vs Spiderman Who Would Win, Wolverine Vs
OPTICAL COHERENCE TOMOGRAPHY
Optical Coherence TomographyOptical coherence tomography (OCT) is a noninvasive imaging an innovation used to obtain high resolution cross-sectional pictures of the retina. OCT is similar to ultrasound testing, other than that imaging is perform by measure up light fairly than sound. OCT procedures the retinal nerve fiber layer thickness in glaucoma and also other conditions of the optic nerve.OrthophoricProper alignment of the 2 eyes. Lack of eye deviation.Papillomacular bundleA collection of retinal ganglion cell that carry the info from the macula (the central retina) to the optic nerve and also on to the brain. If damaged, central visual field defects occur.Peripapillary atrophyThinning the the retina and retinal, colours epithelium in the an ar immediately bordering the optic nerve head. This deserve to be seen in a variety of pathologic and benign conditions.PhotophobiaIn biology, photophobia (adjective: photophobic) ad to an unfavorable response come light. Additionally called "light sensitivity" this is an extreme sensitivity to light and also the aversion to sunlight or well-lit places. In ordinary clinical terms photophobia is not a morbid fear, yet an endure of discomfort or pain come the eyes due to light exposure. Might be connected with excessive tearing. There have the right to be many reasons including inflammation that the iris or cornea.PhotopicA problem of "light adaptation" that is provided in retinal experimentation such together the electroretinogram. Irradiate adaptation is accomplished by exposing a patients eye to diffuse light of middle intensity number of minutes. This can be useful for identify the health of "cones," the well detail and color perceiving cell in the retina.Protanomaly, protanomalousPartial shade deficiency affect the capability to watch the shade red. There are three feasible color vision deficits: red (protan), green (deutan), and also blue (tritan). The suffixes –omaly and also –opia show partial and also complete shade vision deficits, respectively. Therefore, a person who has tritanomaly will have a partial blue color vision deficit when a person who has actually deuteranopia will have a complete green shade deficit.Relative afferent pupillary defect (RAPDAn clues of damage to the visual device which is better on one side 보다 the other. The visibility of a family member afferent pupillary defect (RAPD) method that the pupils constrict less when a light is directed into the affected eye 보다 they do once the exact same light is directed right into the common (or much less affected) eye . The visibility of one RAPD commonly indicates damages to the retina or optic nerve that outcomes in lessened light impulses gift transmitted from the eye to the brain on the impacted side.Retinal ganglion cellsThese cells transmit the info from the various other layers of the retina come the brain. The axons of these cells comprise the optic nerve. Retinal ganglion cells consist of the most superficial cabinet layer in retina and also are prone to damage in a number of an illness entities, consisting of glaucoma.Retinitis pigmentosaA group of hereditary eye problems leading come chronic retinal degeneration, attach by abnormal deposits of pigment. The disease causes a gradual decrease in peripheral or next vision. Connected with night blindness, ns of peripheral vision, tunnel vision, decreased acuity, lack of depth perception, retinal scarring, and also photophobia.ScotomaAn area of partial modification in the ar of vision with partially reduced or completely degenerated intuitive acuity i m sorry is surrounded by a ar of regular vision.ScotopicA condition of "dark adaptation" that is offered in retinal experimentation such as the electroretinogram. Dark adaptation is achieved by placing black color goggles over the patient"s eyes because that a predetermined period of time (usually about 30 minutes). This have the right to be useful for determining health of "rods," or the dim light-detecting cell in the retina.
Septo-optic dysplasiaA clinically heterogeneous disorder loosely defined by any mix of optic nerve hypoplasia, pituitary gland hypoplasia, and midline abnormalities the the brain, including lack of the body callosum and septum pellucidum.StrabismusA condition in i m sorry the eyes space not correctly aligned v each other bring about an inability to focus both eye on a given point. Greek strabismos = squintingTritanopiaA kind of color blindness exhibiting lose of the blue receptor, inherited in one autosomal recessive fashion.Variable expressivityThe idea that individuals with a particular disease process will not each experience the exact same severity that disease. For instance, one person may have actually a milder type of the an illness while another person through the same disease has a more severe manifestation of the disease. This is in contrast to incomplete penetrance.Vision rehabilitation aidsDevices such as magnifiers and also closed circuit television sets the can help people v sub-normal vision see much more and function far better in day come day activities. Additionally known as Low Vision aids.Visual fieldField the vision: The entire area that can be seen when the eye is directed forward, consisting of that i beg your pardon is seen with peripheral vision.Visual ar testingA visual field test is an check that might be performed to analysis a patient"s visual field. The test might be carry out by a technician directly, v the help of a machine, or completely by an automatic machine. Device based tests help diagnostics by enabling a comprehensive printout of the patient"s visual field. See Perimetry