Ch 15 Eyes

Question 1

CN VI (abducens) innervates \_\_\_\_ muscle
CN IV (trochlear) innervates \_\_\_\_\_ muscle
CN III (oculomotor) innervates \_\_\_\_\_ muscles

Answer 1

CN VI: lateral rectus (abduct)
CN IV: superior oblique (in and down)
CN III: all other nerves (superior, inferior and medial rectus, interior oblique

Question 2

Corneal reflex involves CN ___ and ____

Answer 2

CN V (trigeminal): afferent
CN VII (facial): efferent

Question 3

intraocular pressure: balance between amount of ____ and resistance to its outflow at angle of _______

Answer 3

amount of aqueous humour

angle of anterior chamber

Question 4

optic disc: where fibres from ____ converge to form _____ nerve

Answer 4

retina

optic nerve

Question 5

retinal arteries are ____ and ____ compared to veins, grow ______ in calibre near periphery

Answer 5

bright red, narrower

smaller in calibre as they approach periphery

Question 6

macula is on the ____ side of fundus

contains fovea which is area of ______ vision

Answer 6

temporal

sharpest vision

Question 7

Pupillary light reflex
CN ___ is afferent
CN ___ is efferent

Answer 7

CN II afferent

CN III efferent

Question 8

Accommodation tests for _____ and ______

Answer 8

convergence and pupillary constriction

Question 9

macular degeneration is loss of ____ vision

glaucoma is loss of _____ vision from damage to ____

Answer 9

macular degeneration: central loss

glaucoma: peripheral loss, damage to optic nerve

Question 10

Open angle glaucoma:

• aqueous humour is _____
• symptoms:

Closed angle glaucoma:

• aqueous humour is ____
• symptoms:

Answer 10

Open angle:

• aqueous humour slow to drain
• virtually no symptoms
• peripheral vision loss often unnoticed

Close angle:

• angle is blocked, no drainage
• sudden increase in IOP
• blurred vision, light sensitivity, halos around lights, nausea

Question 11

halos around lights may occur with ______

Answer 11

narrow angle glaucoma

Question 12

strabismus is deviation in ______ axis of eye

Answer 12

antero-posterior axis

Question 13

what is anisocoria?

Answer 13

pupils of two different sizes

Question 14

Myopia: light rays focus ____ of eye
-compensate with ____diopter

Hyperopia: light rays focus _____ of eye
-compensate with ____ diopter

Answer 14

Myopia: front of eye
-negative

Hyperopia: behind (if they could pass through)
-positive

Question 15

What is normal cup to disc ratio?

Answer 15

cup width is <0.5 diameter of disc

Question 16

What is normal macula size?

Answer 16

1 DD, located 2DD temporal to disc

Question 17

what are pingueculae?

Answer 17

yellowish elevated nodules from thickening of bulbar conjunctiva

• from prolonged exposure to sun, wind, dust
• occur at 3:00 and 9:00

Question 18

What is arcus senilis?

Answer 18

grey arc around limbus from deposit of lipid

no effect on vision

Question 19

What is blepharitis? signs and symptoms?

Answer 19

inflammation of eyelids

• red, scaly, greasy flakes, crusted eyelid margins
• staph or seborrheic dermatitis at eyelid
  symptoms: burning, itching, tearing, FB sensation, some pain

Question 20

What is a chalazion? signs and symptoms?

Answer 20

beady nodule on eyelid
-infection/cyst of meibomian gland
-NONtender, firm, discrete swelling
if inflamed it will point INWARD (not eyelid margin)

Question 21

What is a hordeolum (stye)? signs and symptoms?

Answer 21

Localized staph infection of hair follicles at eyelid margin

• painful, red, swollen
• pustule at eyelid margin

Question 22

What is dacrocystitis vs dacroadenitis?

Answer 22

dacrocystitis: infection and blockage of lacrimal sac and duct
- pain, swelling, redness to inner canthus
- pressure will produce pus from puncta

dacroadenitis: infection of lacrimal gland
- pain, redness, swelling to outer third of upper eyelid
- from MMM (mumps, measles, mono)

Question 23

What is miosis vs mydriasis?

Answer 23

Miosis: constricted fixed pupils
-from pilocarpine drops for glaucoma, narcotics, iritis, damage to pons

Mydriasis: dilated fixed pupils

• from dilating eye drops, acute glaucoma, trauma
• heralds CNS injury, arrest

Question 24

What is Argyll Robertson Pupil?

Answer 24

• no reaction to light, constrict with acccomodation only
• small and irregular
• with neurosyphilis, brain tumour, meningitis, chronic ETOH

Question 25

What is Horner’s syndrome?

Answer 25

• lesion of sympathetic nerve
• unilateral small regular pupil
• reacts to light and accommodation
• ptosis and anhidrosis also present

Question 26

What is a tonic (Adie’s) pupil?

Answer 26

• sluggish reaction to light and accommodation
• usually unilateral
• no pathological significance

Question 27

Signs and symptoms of acute glaucoma?

Answer 27

• circumcorneal redness around iris
• pupil DILATION
• cornea looks steamy
• sudden clouding of vision and sudden eye pain
• halos around lights
• *critical finding, needs emergency intervention**

Question 28

Signs of symptoms of iritis

Answer 28

• dull red halo around iris and cornea (pronounced around iris)
• may have irregular pupil shape from swelling
• marked photophobia
• constricted pupils
• blurred vision
• throbbing pain
• critical finding, needs immediate referral

Question 29

What is a hyphema?

Answer 29

• blood in anterior chamber
• result of blunt trauma
• suspect scleral rupture or major intraocular trauma
• *emergency**

Question 30

What is a hypopyon?

Answer 30

• purulent matter in anterior chamber
• with iritis and anterior chamber inflammation
• emergency*

Question 31

What are signs of papilledema?

Answer 31

• congestion and elevation of optic disc, blurred margins, hemorrhages
• absence of venous pulsations-
• visual acuity NOT affected
• serious sign of rising ICP

Question 32

Scleral icterus extends up to _____ and is indicative of ________

Answer 32

extends up to cornea

-indicative of jaundice