Eyes Lab Vocabulary Flashcards
Accommodation
Adjustment of the eye for various distances through modification of the lens curvature
Amsler grid
A set of charts with various geometric shapes in black and white, used for detecting defects of the central visual field
Anisocoria
Inequality of the diameter of the pupils; may be normal or congenital
Often normal if inequality is within 1 mm
Aphakia
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
Aqueous humor
The watery transparent liquid containing trace albumin and small amount of salts produced by the iris, ciliary body, and cornea
It circulates through the anterior and posterior chambers of the eye
Astigmatism
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
Cataracts
Opacity of the lens
Most commonly resulting from denaturation of the lens protein caused by aging
Chalazion
Small, hard tumor analogous to sebaceous cyst developing on the eye lids
Formed by the distension of a meibomian gland with secretion
Choroid
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
Ciliary Body
The thickened part of the vascular tunic of the eye that joins the iris with the anterior portion of the choroid
Consists of three zones: ciliary disc, ciliary crown, and ciliary muscle
Cones
The photosensitive, outward-directed, conical process of a cone cell essential for sharp vision and color vision
Only photoreceptor in the fovea centralis and become increasingly interspersed with increasing numbers of rods toward the periphery of the retina
Confrontation
A test for estimating peripheral vision
Conjunctiva
The mucous membrane investing the anterior surface of the eyeball and the posterior surface of the lids
Conjunctivitis
Inflammation of the conjunctiva caused by infectious agents or by allergies
aka Pinkeye
Cornea
The clear, transparent anterior portion of the fibrous coat of the eye comprising about 1/6 of its surface
Chief refractory structure of the eye
Corneal arcus
(called arcus juvenilis if seen in younger people)
Opaque white ring about the corneal periphery, seen in many individuals older than 60 years of age
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 40
Cotton wool spot
An ill-defined yellow area due to infarction of the nerve layer of the retina
Depth perception
Perception of spatial relationships; three dimensional perception
The visual ability to judge depth or distance
Diabetic retinopathy (background)
Condition characterized by dot hemorrhages or microaneurysms and the presence of hard and soft exudates
Diabetic retinopathy (proliferative)
Condition characterized by development of new vessels as a result of anoxic simulation
Vessels grow out of the retina toward the vitreous humor
Diopter
Refractive power of the lens with focal distance of 1 meter
Used as a unit of measurement in refraction
Diplopia
The condition in which a single object is perceived as two objects (double vision)
Drusen
Tiny yellow or white deposits in the retina of the eye or on the optic nerve head
Ectropion
Eversion of an edge or margin as in the edge of the eyelid