visual systems

Question 1

complete optic nerve lesion

Answer 1

monocular vision loss

Question 2

medial optic chiasm lesion (or pituitary adenoma)

Answer 2

bitemporal hemianopia

Question 3

lateral optic chiasm lesion (or internal carotid calcification)

Answer 3

u/l or b/l nasal hemianopia

Question 4

optic tract lesion

Answer 4

c/l homonymous hemianopia (same side lost in each eye c/l to lesion)

Question 5

LGN lesion

Answer 5

c/l homonoymous hemianopia

Question 6

color and form

Answer 6

3 (i/l) - 6 (c/l): parvocellular

Question 7

parietal stream

Answer 7

c/l inferior quadrantonopia

Question 8

temporal stream

Answer 8

c/l superior quadrantonopia

Question 9

PCA occlusion

Answer 9

c/l homonymous hemianopia with macular sparing

Question 10

occulomotor nerve palsy

Answer 10

“down and out”

only LR and SO work

Question 11

trochlear nerve palsy

Answer 11

SO paralysis
“up and in” w/ vertical diplopia and hypertonia

patient complains of neck pain

Question 12

abudcens nerve palsy

Answer 12

LR paralysis

loss of abduction and horizontal diplopia

Question 13

horners syndrome

Answer 13

disruption of dilation (sym fibers to eyes and face)

1. miosis
2. ptosis
3. anhydrosis

Question 14

Puppillary light reflex

Answer 14

Light
retinal gg cells
CN II
optic tract
symapse @ pretectal area
Edinger wesphal nucleus
CN III
pupillary constricotr muscles

Question 15

lesion CN II

Answer 15

loss of consensual AND direct pupillary light reflex

Question 16

lesion CN III

Answer 16

loss of consensual only

Question 17

Argyll-Robertson pupil

Answer 17

pupil doesnt constrict when light shone on it

DOES constrict during accomodation (syphilis)

Question 18

marcus gunn pupil

Answer 18

caused by optic neuritis or retinal disease

eyes dilate when light is shown in affected eye after being shown in unaffected eye

Question 19

right and wrong way eyes

Answer 19

Right way: eyes look twoard lesion and away from paralysis (lesion to hemisphere, affects frontal eye field)

Wrong way: eyes look away from lesion (lesion to pons affecting PPRF- paramedian pontine reticular formation)

Question 20

internuclear opthalmoplegia

Answer 20

lesion to MLF. convergence intact but can’t do conjuctae gaze (eye i/l to lesion does adduct).
horizontal diplopia

Question 21

one and a half syndrome

Answer 21

lesion to MLF, CN VI nucleus & PPRF

abduction only on c/l side
convergence intact

Question 22

Parinaud’s syndrom

Answer 22

pineal gland tumor or hydrocephalus
“vertical gaze palsy”

lesion to dorsal midbrain and pretectal area

1) loss of vertical gaze (MLF)
2) dilated, irrecular pupils
3) colliers sign
4) convergence- retraction nystagmus