Neuro-ophthalmology

Question 1

What causes optic neuritis?

Answer 1

Demyelination of optic nn

- Usually 2’ to MS or ischaemic optic neuropathy (blood clot)

Question 2

Sx optic neuritis (2)

Answer 2

Blurred vision

Retrobulbar pain on movement

Question 3

O/E optic neuritis (3)

Answer 3

Red colour vision
RAPD
Central scotoma

Question 4

If a patient has a repeat episode of optic neuritis, what should be done?

Answer 4

MRI (b/c risk MS)

Question 5

What is papilloedema

Answer 5

Swelling of optic disc due to incr ICP

Question 6

Is papilloedema usually uni or bilateral ?

Answer 6

Bilateral

Question 7

Sx papilloedema (3)

Answer 7

Transient visual obscurations + enlarged blind spots

Gradually progressive

Question 8

O/E (6)

Answer 8

May have - splint haemorrhages, exudates, cotton wool spots, retinal folds
Enlarged blinds spots
Progressive field loss

Question 9

What is AAION

Answer 9

Inflammation of the aa to the optic discs which causes infarction

Question 10

Sx AAION (5)

Answer 10

Temporal headache + 
Jaw claudication 
W loss 
Myalgia 
Visual loss

Question 11

O/E AAION (4)

Answer 11

Raised CRP/ESR
Margins blurred
Cup obliterated
Rest of fundus = pallor

Question 12

Which aa is specifically affected in AAION

Answer 12

Posterior ciliary aa

Question 13

Mx AAION (2)

Answer 13

Urgent high dose steroids
Continue for 2 years
Temporal aa biopsy within 1 week starting Tx

Question 14

Which aa is affected in Non-arteritic AION

Answer 14

Posterior communicating aa

Question 15

O/E NAION (3)

Answer 15

ESR not raised
Swelling not as gross as AAION, visual impairment not as excessive
No systemic Sx

Question 16

What do 50% of patients with NAION have?

Answer 16

HTN

Question 17

Tx NAION

Answer 17

Low dose aspirin

Question 18

Features of optic atrophy (3)

Answer 18

Afferent pupillary defect
Optic nn - atrophic + palsies
Loss surface capillaries

Question 19

Which mm are affected in CN III palsy? (5)

Answer 19

MR
IF
SR
LPS
IO

Question 20

Appearance eyes IIICN palsy (3)

Answer 20

Eyes point down + out
Ptosis
Dilated/mydriasis

Question 21

Which mm is affected in CN IV palsy?

Answer 21

SO

Question 22

Appearance eyes CN IV palsy

Answer 22

Eyes can’t look down + in

Question 23

What may a patient with CN IV palsy complain of when looking down + in?

Answer 23

Vertical diplopia

Question 24

What is bilateral CN IV palsy associated with?

Answer 24

Head injuries

Question 25

What mm is affected in CN VI palsy?

Answer 25

LR

Question 26

Appearance CN VI palsy

Answer 26

Pt can't abduct | Eye may drift medially b/c pull medial rectus

Question 27

What 2 things should you test to see if a patient has CN VII palsy?

Answer 27

Corneal sensation | Bells

Question 28

What part of the visual circuit is affected if patient presents with bitemporal hemianopia

Answer 28

Optic chiasm

Question 29

Causes of bitemporal hemianopia (3)

Answer 29

Pit tumour Meningioma Aneurysm of ant communicating aa

Question 30

What part of the visual circuit is affected if patient presents with homonymous hemianopia

Answer 30

Optic tract lesion

Question 31

Cause of homonymous hemianopia

Answer 31

Usually CVA

Question 32

Which loop is affected in L superior quandrantopia

Answer 32

Meyers

Question 33

What cortex of brain is affected in L superior quadrantopia

Answer 33

Temporal lobe

Question 34

What loop is affected in L inferior quadrantopia

Answer 34

Baum's

Question 35

What cortex of brain is affected in L inferior quadrantopia

Answer 35

Parietal

Question 36

What part of brain is affected if you get homonymous hemianopia w/ macular sparing ?

Answer 36

Visual cortex CVA

Question 37

Why do you get macular sparing?

Answer 37

B/c macular fibres recieve a sep blood supply to peripheral visual cortex

Question 38

What is an afferent pupil defect?

Answer 38

Disruption of fibres travelling from RCG to PTN and from PTN to same + contralateral EWN

Question 39

Affect of Afferent pupil defect on pupillary responses

Answer 39

No consensual or direct response

Question 40

Affect of RAPD on pupillary responses

Answer 40

Reduce light + consensual response | Pupil dilates on swinging light test

Question 41

What causes Horner's syndrome?

Answer 41

Lesion of sympathetic pathway

Question 42

PS Horner's syndrome

Answer 42

Affected pupil smaller than usual Apparent enophthalmos Partial ptosis

Question 43

Cause fo Argyll Robertson Pupils

Answer 43

Congenital syphillis

Question 44

Appearance + response of Argyll Robertson Pupils (4)

Answer 44

Pupils small + irreg Sluggish light responses Light near dissociation Sometimes blind

Question 45

Appearance + response Argyll Robertson Pupils (3)

Answer 45

Efferent defect SLugish pupil response LND