Labs 6-7: Eyes Flashcards
1
Q
Accommodation
A
- adjustment of eye for various distances through modification of the lens curvature
2
Q
Amsler grid
A
- set of charts with various geometric shapes in black and white used for detecting defects of central visual field
3
Q
Anisocoria
A
- inequality of the diameter of the pupils, may be normal or congenital, often normal if inequality is within 1 mm
4
Q
Aphakia
A
- condition in which part or all of the crystalline lens of eye is absent, usually because of surgical removal for the treatment of cataracts
5
Q
Aqueous humor
A
- watery transparent liquid containing trace albumin and small amounts of salts produced by iris, ciliary body and cornea. It circulates through anterior and posterior chambers of eye
6
Q
Astigmatism
A
- abnormal condition in which light rays cannot be focused clearly in a point on the retina because of an irregular curvature of the cornea or lens
7
Q
Cataracts
A
- opacity of the lens, most commonly resulting from denaturation of the lens protein caused by aging
8
Q
Chalazion
A
- small, hard tumor analogous to sebaceous cyst developing on the eye lids, formed by distention of meibomian gland with secretion
9
Q
Choroid
A
- middle vascular tunic of eye lying between retina and sclera; dark brow vascular coat – made up on five layers
10
Q
Ciliary body
A
- thickened part of vascular tunic of eye that joins the iris with the anterior portion of choroid, consists of three zones: ciliary disk, ciliary crown, ciliary muscle
11
Q
Cones
A
- Color vision
12
Q
Confrontation
A
- test for estimating peripheral vision
13
Q
Conjunctiva
A
- mucous membrane investing the anterior surface of the eyeball and the posterior surface of the lids
14
Q
Cornea
A
- transparent anterior portion of the fibrous coat of the eye comprising about 1/6th of its surface, chief refractory surface of eye
15
Q
Corneal arcus
A
- opaque white ring about corneal periphery, seen in many individuals older than 60 years of age. This is due to deposit of lipids in cornea or to hyaline degradation. May indicate lipid disorder
16
Q
Cotton wool spot
A
- ill-defined yellow areas due to infarction of nerve layer of retina
17
Q
Diabetic retinopathy (background):
A
- condition characterized by dot hemorrhages or microaneurysms and the presence of hard and soft exudates
18
Q
Diabetic retionapthy (proliferative):
A
- condition characterized by development of new vessels as a result of anoxic stimulation, vessels grow out of retina toward the vitreous humor
19
Q
Diopter
A
- refractive power of lens with focal distance of 1 meter, used as unit of measurement in refraction
20
Q
Diplopia
A
- condition in which a single object is perceived as two objects (double vision)
21
Q
Drusen
A
- tiny yellow or white deposits in retina of eye or on the optic nerve head
22
Q
Ectropion
A
- eversion/outward rolling of an edge or margin, as the edge of the eyelid
23
Q
Episcleritis
A
- inflammation of superficial layers of sclera located in front of insertion of the rectus muscle
24
Q
Entropion
A
- inversion/inward rolling of edge or magin, as the edge of the eyelid
25
Q
Exophthalmos
A
- increase in volume of orbital content, causing protrusion of globes forward. May be bilateral or unilateral, most common cause = Graves’ disease, but when unilaterally, retro-orbital tumor should be suspected
26
Q
Farsightedness
A
- aka hyperopia
- error or refraction causing parallel rays to come to focus behind retina when accommodation is relaxed
27
Q
Nearsightedness
A
- aka myopia
- refractive error in which light rays entering eye are brought into focus in front of retina
28
Q
Glaucoma
A
- disease of optic nerve wherein nerve cells die, producing increased cupping appearance in optic nerve. An abnormal condition of elevated pressure within an eye resulting from obstruction of outflow of aqueous humor. Produces defects in visual field and may result in blindness
29
Q
Hemianopia
A
- blindness for half field of vision in one or both eyes
30
Q
Hordeolum
A
- aka sty
- suppurative inflammation of a sebaceous gland of eyelid
31
Q
Hypertelorism
A
- eyes spaced widely apart
32
Q
Hyphema
A
- blood in anterior chamber of eye in front of iris