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
33
Q
Iritis
A
- inflammation of iris
34
Q
Legal blindness
A
- In US, person is considered legally blind when vision in better eye corrected by glasses is 20/200. In case of constricted field of vision: 20 degrees or less in better eye
35
Q
Macula
A
- aka fovea
- site of central vision
36
Q
Mydriasis
A
- pupillary dilation
37
Q
Miosis
A
- abnormal contraction of pupils
38
Q
Night blindness
A
- decreased ability to see in reduced illumination. Seen in pts with impaired rod function, often associated with deficiency in vitamin A
39
Q
Nystagmus
A
- involuntary rhythmic movements of the eyes, oscillations may be horizontal, vertical, rotary or mixed
40
Q
Papilledema
A
- edema of the optic disc resulting in loss of definition of the disc margin, the cause often is increased ICP
41
Q
Peripheral vision
A
- vision resulting from retinal stimulation beyond the macula
42
Q
Pinguecula
A
- harmless yellowish triangular nodule in bulbar conjunctiva on either side of the iris that stops at the limbus
43
Q
Presbyopia
A
- hyperopia (farsightedness) and impaired near vision from loss of lens elasticity, generally developing during middle age
44
Q
Pterygium
A
- triangular patch like thickening of bulbar conjunctiva that grows slowly to outer surface of cornea usually from nasal side and may cover a portion of the cornea
45
Q
Ptosis
A
- drooping of one or both upper eyelids
46
Q
Punctum
A
- tiny aperture/opening in the margin of each eyelid that opens to the lacrimal duct
47
Q
Red reflex
A
- response caused by light illuminating the retina
48
Q
Retinitis pigmentosa
A
- chronic progressive disease which may occur in childhood, characterized by degeneration of the retinal neuroepithelium
49
Q
Retinoblastoma
A
- embryonic malignant glioma arising from the retina usually during first two years of life. Initial diagnostic finding is usually a yellowish or white reflex seen at the pupil
50
Q
Strabismus
A
- condition in which both eyes do not focus on the same object simultaneously, however either eye can focus independently
51
Q
Uveitis
A
- inflammation of iris, ciliary body, choroid or entire uvea
52
Q
Vitreous body
A
- transparent jellylike substance that fills the cavity of the eyeball, enclosed by the hyaloids membrane, it is comprised of delicate network enclosed in its meshes a watery fluid
53
Q
Xanthelesma
A
- an elevated plaque commonly found on nasal portion of the eyelid due to elevated cholesterol
54
Q
Describe how to assess near vision
A
- Use a Rosenbaum pocket eye chart. Pt may wear reading glasses if they normally do. Test must be completed for each eye. Pt holds chart comfortable distance, no closer than 14 inches.
- Pt reads smallest line right to left. Cover eye and repeat left to right
- Normal: pt can read chart at distance of 14 inches or greater
- Abnormal: pt cannot read chart at distance of 14 inches or greater
55
Q
Describe how to assess distance vision
A
- Use a Snellen chart. Pt stands 20 feet from chart. If pt wears glasses for distance, they should do so for test. Right eye tested first, cover left
- Read smallest line possible from left to right.
- Cover right, read smallest line possible from right to left
- If pt cannot read largest letter at 3 feet, hold up fingers. If they cannot count fingers, wave hand. If they cannot detect that, follow with light perception tests
- Normal: 20/12 to 20/25
- Abnormal: 20/30-20/70 (near normal), 20/80-20/160 (moderate low), 20/200-20/400 (severe low)
- Vision not correctible to better than 20/200 is considered legally blind
56
Q
Describe how to evaluate peripheral vision
A
- Stand facing pt about 1 meter away
- Ask pt to cover his/her left eye while you close your right eye. Pt should keep eye glasses on or contacts in, if needed
- Instruct pt to keep looking straight at your uncovered eye and not to move eyes during test
- Slowly bring fingers into visual field halfway between you and the pt at 45 degree angles into the 4 quadrants. Ask pt to report number of fingers being displayed
- Compare the time the pt first sees your hand with time you first see your hand
- Normal: pt should be able to see and report number of fingers at approx same time you are able to see and count fingers
- Abnormal: pt unable to see examiners hands at about the same time the examiner can
57
Q
What are possible causes of peripheral vision deficits?
A
- Stroke, central retinal vascular occlusion, retinal detachment, optic neuropathy, compression of optic chiasm
58
Q
Name extraocular muscles. What moves eyes left, right, right/up, right/down, left/up, left/down
A
- SO4LR6 restIII
- Rectus (superior, medial, lateral, inferior) and superior/inferior oblique
1. ) Left: left lateral rectus, right medial rectus
2. ) Right: left medial rectus, right lateral rectus
3. ) Right up: right superior rectus, left inferior oblique
4. ) Right down: right inferior rectus, left superior oblique
5. ) Left up: left superior rectus, right inferior oblique
6. ) Left down: left inferior rectus, right superior oblique
59
Q
How to assess EO muscles?
A
- Have pt face you and hold head still
- Have pt follow your fingers with their eyes
- Assess motion by drawing X and + with index finger
- Normal: smooth movements to all cardinal points
- Abnormal: jerking or drifting (nystagmus) and involuntary movements
- Can test for convergence by bringing finger towards pt and asking them to follow finger
60
Q
Difficulty with convergence of eyes may indicate what condition?
A
- Hyperthyroidism
61
Q
Normal pupil size
A
- Round, equal and 5 to 8 mm in diameter. Not abnormal for pupils to be different sizes in each eye, but no more than 1 mm and as long as papillary reactions are normal
62
Q
Causes of different pupil sizes?
A
- trauma, glaucoma, impairment of PSNS and SNS nerve supply
63
Q
How to test for pupillary reaction to light? Reflex grading scale
A
- Ask pt to focus on distant object in room and dim lights
- When light source is held in front of one eye and you watch ipsilateral constriction – this is direct pupil response
- When light source is held in front of one eye and you watch contralateral constriction – this is consensual pupil response
0: no response
1+: sluggish or diminished
2+: active or expected
3+: more brisk than expected, slightly hyperactive
4+: brisk, hyperactive with intermittent or transient clonus - normal: pupils should receive identical signals from midbrain therefore constricting both pupils equally
- abnormal: constriction of one, but not the other (or slow in the other)
64
Q
How to test pupils for near reaction?
A
- This is done by having pt shift gaze from far object to a near object approximately 10 cm away from pt’s eyes
- Check for constriction of pupils, convergence of eyes
65
Q
What is the swinging flashlight test? What does it test for? How do you perform this test?
A
- Test for optic nerve dysfunction
Steps:
1.) Dim room light
2.) Have pt fixate on object 15 or more fee away
3.) Shine light penlight in front of one eye for 1 second and observe pupil response
4.) Move rapidly across bridge of nose to front of other eye for 1 second and observe the pupils response
5.) Then shift back to first eye, repeat
Normal test: pupils constrict and respond to light consensually
Abnormal test: slow dilation without initial constriction may indicate lesion of optic nerve or retinal lesion (Marcus Gunn pupil aka relative afferent pupillary defect)
66
Q
What is the lateral penlight test? What is it testing? How do you perform this test?
A
- This test observes anterior chamber depth, testing for glaucoma
Steps:
1.) Shine light from temporal side of head across front of eye parallel to plane of iris
2.) Observe nasal aspect of iris. 2/3rd or more of nasal iris in shadow may indicate shallow chamber or narrow angle
Normal test: no shadow on medial eye
Abnormal test: shadow on medial eye
67
Q
What is the corneal light reflex? What is it testing? How do you perform this test?
A
- Tests ocular alignment looking for presence of esotropia, exotropia, hypertropia or hypotropia
Steps: - Hold penlight directly in front of pt at distance of two feet
- Compare the position of the light reflection by the cornea of each eye
Normal: normal reflection is symmetrically placed on pupils
Abnormal: not symmetric
• Be careful of epicanthal fold, which may give appearance of esotropia
68
Q
Esotropia
A
- Medial-facing eye
69
Q
Exotropia
A
- Lateral-facing eye
70
Q
Hypertropia
A
- Upward-facing eye
71
Q
Hypotropia
A
- Downward-facing eye
72
Q
What test is used to detect tropias?
A
- Cover test
73
Q
What is the cover test? What is being tested? How do you perform this test?
A
- Test is used to detect tropias in pts over age of 6 or 7 months
Steps: - Ask pt to focus on a specific point or object across the room
- Cover one of the pt’s eyes with spoon or hand and observe movement in uncovered eye
- Repeat exam on other eye
Normal results: no shifting of eyes, therefore no tropia
Abnormal results
1.) Eye moving inward, originally outward, therefore exotropic
2.) Eye moving outward, originally inward, therefore esotropic
3.) Eye moving up, originally down, therefore hypotropic
4.) Eye moving down, originally up, therefore hypertropic
74
Q
What test is used to detect phoria?
A
- Cover-uncover test
75
Q
What is cover-uncover test? What does it test? How to perform it?
A
- Used to detect presence of a phoria
Steps: - Ask pt to focus on distant object in room
- Cover and uncover one eye and observe whether that eye moves when covered
- Repeat with other eye
Normal: no movement in covered eye
Abnormal: movement detected in covered eye
1.) Exophoria if eye moves outward
2.) Esophoria if eye moves inward
76
Q
What does corneal touch reflex test? How to perform this test?
A
- Tests trigeminal nerve (V1 and V2) and facial nerve
Steps: - Have pt look up and away
- Gently touch the other side of the cornea with a wisp of cotto
Normal: stimulation of one cornea will usually cause bilateral blinking
Abnormal: pt does not respond or blink during the test
77
Q
When is AV nicking of retina seen?
A
- Hypertension
78
Q
What do new vessels on the optic disc usually indicate?
A
- Proliferative diabetic retinopathy
79
Q
What could a pale and clearly demarcated optic disc indicate?
A
- Optic atrophy
80
Q
What does abnormal cupping of optic disc usually indicate?
A
- Glaucoma
