Eyes

Question 1

Eye development in children

Answer 1

• macula develops 4-8 months- 80% NB farsighted (decreases 7-8yrs)- eyeball adult size age 8

Question 2

Eye Developments in Older Adults

Answer 2

• drooping (loss of skin elasticity)- lipids gather at iris/limbus- lens cannot change shape (presbyopia), discolors/thickens (cataract)- floaters in vitreous humor- glaucoma (increased pressure)

Question 3

distance vision acuity test

Answer 3

Snellen Chart- patient at 20 ft- 20/20 (distance/where normal eye could read same line)- 20/200 = legally blind

Question 4

myopia

Answer 4

nearsighted

Question 5

hyperopia

Answer 5

farsighted

Question 6

presbyopia

Answer 6

> 40; trouble reading due to loss of ability of lens to accommodate (not shape of eye)

Question 7

approximate completely

Answer 7

when upper lid and bottom lid close completely

Question 8

Pupil size

Answer 8

3-5mm 5 mydriasis (increase intraocular pressure - glaucoma, increase intracranial pressure)

Question 9

strabismus

Answer 9

weakness or paralysis of 1+ extraocular muscles, due to congenital defect, orbital fracture, trauma, or CVA-related palsy

Question 10

nystagmus

Answer 10

when eyes will oscillate in place, only normal in far lateral view

Question 11

visual pathways: optic nerve cut

Answer 11

blind in that eye, CN2 does not cross over

Question 12

visual pathways: chiasm cut

Answer 12

bitemporal hemianopsia: blind in temporal vision field; only the fiber on the nasal side crosses over chiasm (nasal views temporal)

Question 13

visual pathways: optic tract

Answer 13

will lose nasal field in side that was affected and temporal field of opposite side

Question 14

optic disc

Answer 14

fibers converge to form CN2; on nasal side, should have distinct edges; creamy yellow/pink in color

Question 15

physiologic cup

Answer 15

small circle area inside disc - where blood vessels exit and enter

Question 16

retinal vessels

Answer 16

4 - paired artery and vein; arteries are brighter red and narrower

Question 17

general background

Answer 17

varies in color based on skin color

Question 18

macula

Answer 18

temporal side, darker pigmented; surrounds fovea centralis (sharpest vision)

Question 19

A-V nicking

Answer 19

artery crosses vein and vein disappears (common in HTN)

Question 20

papilledema

Answer 20

• inflammation of optic disc due to intracranial pressure- cloudy around disc and no pulsations

Question 21

Conjunctiva

Answer 21

transparent, thin mucous membrane protective layers- palpebral: lines lids, many blood vessels (clear/pink)- bulbar: overlays eyeball (clear/white sclera shows)

Question 22

limbus

Answer 22

where 2 conjunctiva merge with cornea

Question 23

lacrimal apparatus

Answer 23

(upper outer area of eye) - provides constant irrigation to keep cornea/conjunctiva moist/lubricated- secretes tears

Question 24

3 coats/layers of the eye

Answer 24

sclera, choriod, retina

Question 25

sclera

Answer 25

outer fibrous layer; bends light rays to be focused on retina; touch stimulates blinking

Question 26

choroid

Answer 26

middle vascular - supplies blood to retina

Question 27

ciliary body

Answer 27

muscles controls thickness of lens

Question 28

lens

Answer 28

biconvex dish, transparent; keeps objects focused on retina; thickness controlled by ciliary body

Question 29

anterior chamber

Answer 29

posterior to cornea, anterior to iris/lens, contains aqueous humor - continuous flow for nutrients and drain of metabolic waste(amt determined intraocular pressure)

Question 30

retina

Answer 30

inner nervous/visual receptive layer; light waves converted to nerve impulses

Question 31

fixation

Answer 31

reflex direction of eye towards object attracting attention; "smooth pursuits"

Question 32

accommodation

Answer 32

adaptation of the eye for near vision - increases curvature of lens by mvmt of ciliary muscles - seen by:- convergence and constriction