Anterior ischaemic optic neuropathy

Question 1

define Anterior ischaemic optic neuropathy

Answer 1

ischaemia of the 1mm segment of the optic nerve head (optic disc) and results in visible disc swelling

Question 2

state the two types of Anterior ischaemic optic neuropathy

Answer 2

non-arteritic AAION

arteritic NAION

Question 3

define arteritic Anterior ischaemic optic neuropathy

Answer 3

acute painful optic neuroapthy

usually in elder patients over 50

-can cause permanent loss of vision

Question 4

basic pathophys of arteritic Anterior ischaemic optic neuropathy

Answer 4

ischaemia occurs at head of optic nerve
-due to structural crowding of the nerve fibers, impairing perfusion and leading to optic disc oedema

-inflammation and subsequent thrombosis of the short posterior ciliary arteries (which originitate form the ophthalmic artery)– this causes optic disc infarction

Question 5

what causes arteritic Anterior ischaemic optic neuropathy

Answer 5

temporal arteritis (giant cell arteritis)

Question 6

syx of arteritic Anterior ischaemic optic neuropathy 6

Answer 6

sudden often painful loss of vision
then:

same as for temporal arteritis

-jaw claudication
-sclap tenderness
-unintentional weight loss
-fatigue
-myalgia
-loss of appeitie

Question 7

what blood tests can be raised in arteritic Anterior ischaemic optic neuropathy

Answer 7

ESR

CRP

platelet count (thombocytosis)

Question 8

diagnosis of arteritic Anterior ischaemic optic neuropathy 5

Answer 8

prompt Dx critical as EYE EMERGENCY

blood tests (ESR and CRP elevated=97% specificity)

platelts

temporal artery biopsy

MRI

OCT

Question 9

why is arteritic Anterior ischaemic optic neuropathy an eye emergency

Answer 9

the sudden blindness in the first eye is often followed if left untreated by sudden blindness in the second eye

Question 10

management of arteritic Anterior ischaemic optic neuropathy

Answer 10

v long course of ssteroids

Question 11

signs of arteritic Anterior ischaemic optic neuropathy (3 fundoscopy, 4physical exam)

Answer 11

fundoscopy
-swoelln optic disc and pale
-retinal cotton wool spots
-somtimes central retinal artery occlusion

physical exam
-diplopia-
-ptosis
-nystagmus
-pain on palpation of temporal artery

Question 12

syx of non-arteritic anterior ischaemic optic neuropathy

Answer 12

typically suddenly upon wakening
-unilateral

vision is obscured by dark shadow, often involving either upper or lower half of vision
-usually the area closer to the nose

NO PAIN

Question 13

risk factors for non-arteritic anterior ischaemic optic neuropathy 2

Answer 13

crowded optic disc

general CV risk factors
-DM
-HT
-hyperlipidaemia

Question 14

diagnosis of non-arteritic anterior ischaemic optic neuropathy

Answer 14

imporatnt to distinguish from arteritic anterior ischaemic optic neuropathy (as this is an emergency)

Question 15

important distinction between non-arteritic anterior ischaemic optic neuropathy and arteritic anterior ischaemic optic neuropathy

Answer 15

arteritic- caused by temporal arteritis
-most result in nearly complete vision loss

non-arteritic
-only a few cases result in near total loss of vision

Question 16

define non-arteritic anterior ischaemic optic neuropathy

Answer 16

an isolated white-matter stroke of teh optic nerve

the most common causes of sudden optice-nerve related vision loss
-often bilaterally

Question 17

management of non-arteritic anterior ischaemic optic neuropathy

Answer 17

no real treatmetns

-possible role of sterioods

reduce risk factors