41a - Visual Loss Disorders

Question 1

What is amaurosis fugax?

Answer 1

fleeting loss of vision

Question 2

What should simultaneous transient loss of bilateral vision make you think?

Answer 2

basilar artery insufficiency

Question 3

What is short-lived loss of vision in one eye associated with usually?

Answer 3

papilledema

Question 4

What should pain on eye movment accompanied with loss of central vision and relative afferent pupillary defect make you think?

Answer 4

optic neuritis

Question 5

How far away could a person with 20/20 vision read a 20/50 letter?

Answer 5

50 feet away.

Question 6

What is the numerator of the acuity fraction mean?

denominator?

Answer 6

testing distance

denominator is size of test letter

Question 7

What does OD 20/40 mean on a prescription?

Answer 7

OD = right eye. patient could read 40pt font at 20 feet.

Question 8

What does OS 20/10 mean?

Answer 8

patient has better than ‘perfect’ vision in left eye

can read 10pt font from 20 ft away.

Question 9

How would you check for a RAPD?

Answer 9

Swinging flashlight test. shine light into one eye, then immediately move light in a straight line directly into other eye. Pupils should stay the same.
Afferent defect will have constriction of both pupils with light in first eye, and dilation of both with light in second.
Efferent defect will have constriction in one pupil and dilation in the other no matter which eye the light is in.

Question 10

What is major weakness of confrontation visual testing?

Answer 10

will NOT detect subtle VF defects

Question 11

Where would a lesion that caused congrous HH be?

Answer 11

in the occipital cortex

Question 12

Where would a lesion that caused incongrous HH be?

Answer 12

more anterior (not in the occipital cortex)

Question 13

What is clinical presentation of optic neuritis?

Answer 13

sudden visoin loss of one eye in a young or middle aged adult.
pain w/ movement sometimes
afferent pupillary defect
central VF defect
Color desaturation in affected eye (particularly red)
disc normal or swollen

Question 14

What is treatment for optic neurtitis?

Answer 14

IV corticosteroids. Prognosis usually good.

Question 15

What disease is optic neuritis often seen in?

Answer 15

MS

Question 16

What will a lesion of the optic chiasm cause?

Answer 16

reduced VA in one or both eyes
bitemproal hemianopsia (asymmetric)
may devleop optic atrophy

Question 17

What is most common cause of optic chiasm lesion?

Answer 17

pituitary adenomaw

Question 18

What VF defect would a post-chiasmal lesion cause?

Answer 18

homonymous hemianopsia

Question 19

What is clinical presentation of papilledema?

Answer 19

VA normal
VF full with enlarged blind spot
no pain w/ movement
no afferent pupil defect
heachaches, N/v  (high ICP)
CN6 palsy

Question 20

What is common cause of optic atrophy with large optic cups?

Answer 20

glaucoma

Question 21

What are early signs of open angle glaucoma? LAte?

Answer 21

none. no symptoms.

Late = central vision loss

Question 22

older Patient has acute loss of vision in one eye.
afferent pupil defect
disc swollen and pale
has altitudinal hemianopsia
Diagnosis? What else should you check for?

Answer 22

ishcemic optic neuropathy.

Should also check for temporal arteritis