Eye Lab Vocab Flashcards
adjustment of the eye for various distances through modification of the lens curvature
Accommodation
a set of charts with various geometric shapes in black and white, used for detecting defects of the central visual field
Amsler Grid
inequality of the diameter of the pupils; may be normal or congenital. often normal if inequality is within 1mm
Anisocoria
a condition in which part or all of the crystalline lens of the eye is absent, usually because of surgical removal for the treatment of cataracts
Aphakia
the watery transparent liquid containing trace albumin and small amount of salts
Aqueous Humor
an abnormal condition in which the light rays cannot be focused clearly in a point on the retina because of an irregular curvature of the cornea or lens
Astigmatism
opacity of the lens; most commonly resulting from denaturation of the lens protein caused by aging
Cataracts
small, hard tumor analogous to sebaceous cyst developing on the eye lids, formed by the distention of a meibomian gland with secretion
Chalazion
the middle vascular tunic of the eye lying between the retina and the sclera. dark brown vascular coat of the eye between the sclera and retina, extending from ora serrata to optic nerve. consists of blood vessels united by connective tissue containing pigmented cells and is made up of five layers
Choroid
the thickened part of the vascular tunic of the eye that joins the iris with the anterior portion of the choroid. consist of three zones: ciliary disk, ciliary crown, and ciliary muscle
Ciliary body
the photosensitive, outward-directed, conical process of a cone cell essential for sharp vision and color vision; these are the only photoreceptor in the fovea centralis and become interspersed with increasing numbers of rods toward the periphery of the retina
Cones
a test for estimating peripheral vision
Confrontation
the mucous membrane investing the anterior surface of the eyeball and the posterior surface of the lids
Conjunctiva
inflammation of the conjunctiva caused by infectious agents or by allergies; commonly called pink eye
Conjunctivitis
the clear, transparent anterior portion of the fibrous coat of the eye comprising about one sixth of its surface. it is the chief refractory structure of the eye
Cornea
opaque white ring about corneal periphery, seen in many individuals older than 60 years of age. this is due to deposit of lipids in the cornea or to hyaline degeneration. may indicate a lipid disorder, most commonly type II hyperlipidemia if present before the 40 years of age
Corneal Arcus (if seen in younger people, it is called arcus juvenilis)
an ill-defined yellow area due to infarction of the nerve layer of the retina
Cotton Wool Spot
perception of spatial relationships; three dimensional perception. the visual ability to judge depth or distance
Dept Perception
a condition characterized by dot hemorrhages or microaneurysms and the presence of hard and soft exudates
Diabetic Retinopathy (background)
condition characterized by development of new vessels as a result of anoxic stimulation; vessels grow out of the retina toward the vitreous humor
Diabetic Retinopathy (proliferative)
refractive power of the lens with focal distance of 1 meter, used as unit of measurement in refraction
Diopter
the condition in which a single object is perceived as two objects (double vision)
Diplopia
tiny yellow or white deposits in the retina of the eye or on the optic nerve head
Drusen
eversion (outward rolling) of an edge or margin; as the edge of the eyelid
Ectropion (ect- outside)
inflammation of the superficial layers of the sclera located in front of the insertion of the rectus muscle
Episcleritis
inversion (inward rolling) of an edge or margin; especially the margin of the lower eyelid
Entropion (ent- inside)
an increase in the volume of the orbital content, causing a protusion of the globes forward. may be uni- or bilateral.
Exopthalmos
Graves’ disease is the most common cause of bilateral.
retro-orbital tumor should be suspected if unilateral
an error of refraction in which, with accomodation completely relaxed, parallel rays come to focus behind the retina
Farsigntedness
nerve cells in the optic nerve die, producing increased cupping appearance of the nerve. elevated pressure within an eye result from obstruction of the outflow of aqueous humor. defects in visual field and can lead to blindness
Glaucoma
blindness for half the field of vision in one or both eyes
Hemianopia
suppurative inflammation of a sebaceous gland of the eyelid
Hordeolum (sty)
refractive error where light rays entering the eye are focused behind the retina
Hyperopia (farsigntedness)
eyes spaced widely apart
Hypertelorism
blood in the anterior chamber of the eye in front of the iris
Hyphema
colored contractile membrane suspended between the lens and cornea in the aqueous humor of the eye, separating the anterior and posterior chambers of the eyeball and perforated in the center by the pupil. regulates entrance of light by contraction and dilation
iris
Legal Blindness
in the US, a person is usually legally blind if the better eye with corrected lens has a vision of 20/200 or less. in the case of constricted field of vision: 20 degrees or less in the better eye
site of central vision
Macula (aka fovea)
pupillary dilation
Mydriasis
abnormal contraction of pupils
Miosis
condition result from refractive error where the light rays entering the eye are focused in front of the retina
Myopia (nearsightedness)
patients with impaired rod function may experience decreased ability to see in reduced illumination; often associated with a deficiency of vitamin A
Night Blindness
involuntary rhythmic movements of the eyes; oscillations may be horizontal, vertical, rotary, or mixed
Nystagmus
edema of the optic disc resulting in loss of definition of the disc margin; often caused by increased intracranial pressure
Papilledema
vision resulting from retinal stimulation beyond the macula
Peripheral vision
harmless yellowish triangular nodule in the bulbar conjunctiva on either side of the iris that stops at the limbus
Pinguecula
hyperopia and impaired near vision from loss of lens elasticity, usually develop during middle age
Presbyopia
triangular (patch-like) thickening of the bulbar conjunctiva that grows slowly to the outer surface of the cornea, usually from the nasal side, and may cover a portion of the cornea
Pterygium
drooping of one or both upper eyelids
Ptosis
tiny aperture (opening) in the margin of each eyelid that opens to the lacrimal duct
Punctum
response caused by light illuminating of the retina
Red Reflex
act of determining the nature and degree of the refractive errors in the eye and correction of them by lenses
Refraction
sensory network of the eye that transforms light impulses into electrical impulses, which are transmitted through the optic nerve
Retina
chronic progressive disease, may occur in childhood, characterized by degeneration of the retinal neuroepithelium
Retinitis Pigmentosa
embryonic malignant glioma arising from the retina usually during the first two years of life. initial diagnostic finding is usually a yellowish or white light reflex seen at the pupil (Cat’s eye reflex)
Retinoblastoma
photosensitive, outward-directed process of a rhodopsin-containing rod cell in the external granular layer of the retina; many millions of such rods, together with the cones, form the photoreceptive layer of rods and cones
Rods
tough white fibrous tissue which covers the so-called white of the eye. it extends from the optic nerve to the cornea
Sclera
superficial and deep inflammation of the sclera
Scleritis
condition where both eyes do not focus on the same object simultaneously, but either eye can focus independently
Strabismus
inflammation of the iris, ciliary body, and choroid, or the entire uvea
Uveitis
transparent jelly-like substance that fills the cavity of the eyeball, enclosed by the hyaloid membrane; it is composed of a delicate network (vitreous stroma) enclosing in its meshes a watery fluid (vitreous humor)
Vitreous Body
elevated plague commonly found on the nasal portion of the eyelid due to elevated cholesterol
Xanthelasma
