57Optic Neuropathies

OPTIC NEUROPATHIES

Marwan Salah Salman MD. Ass. Professor of ophthalmology PhD Ophthalmology F.I.C.O Cambridge university Head of unit of ophthalmology Universty of tikrit ,college of medicine

OPTIC NEUROPATHIES

1. Clinical features
2. Special investigations
3. Optic neuritis
4. Anterior ischaemic optic neuropathy (AION)
Retrobulbar neuritis Papillitis Neuroretinitis

Signs of optic nerve dysfunction

Reduced visual acuity
Diminished light brightness sensitivity
Dyschromatopsia
Afferent pupillary conduction defect

Applied anatomy of afferent conduction defect

Anatomical pathway
Signs
Equal pupil size Light reaction - ipsilateral direct is absent or diminished - consensual is normal Near reflex is normal in both eyes Total defect (no PL) = amaurotic pupil Relative defect = Marcus Gunn pupil
3rd

Visual field defects

Central scotoma
Altitudinal
Nerve fibre bundle
Centrocaecal scotoma

Optic disc changes

Normal
Papilloedema
Papillitis and neuroretinitis
Swelling
Optic nerve sheath meningioma
Occasionally optic nerve glioma
Optico-ciliary shunts
Postneuritic
Compression
Atrophy
AION
Hereditary optic atrophies

Special investigations

Classification of optic neuritis
Retrobulbar neuritis (normal disc)
Demyelination - most common
Sinus-related (ethmoiditis)
Lyme disease
Papillitis (hyperaemia and oedema)
Viral infections and immunization in children (bilateral)
Demyelination (uncommon)
Syphilis
Neuroretinitis (papillitis and macular star)
Cat-scratch fever
Lyme disease
Syphilis

Non-arteritic AION

Pale disc with diffuse or sectorial oedema
Eventually bilateral in 30% (give aspirin)
Age - 45-65 years
Altitudinal field defect
Presentation
Acute signs
Few, small splinter-shaped haemorrhages
Resolution of oedema and haemorrhages
Optic atrophy and variable visual loss
Late signs

FA in acute non-arteritic AION

Generalized hyperfluorescence
Increasing localized hyperfluorescence
Localized hyperfluorescence

Superficial temporal arteritis

Headache
Age - 65-80 years
Scalp tenderness
Presentation
Superficial temporal arteritis
Jaw claudication
Polymyalgia rheumatica
Temporal artery biopsy
ESR - often > 60, but normal in 20%
C-reactive protein - always raised
Special investigations
Acute visual loss


Arteritic AION
Affects about 25% of untreated patients with giant cell arteritis
Severe acute visual loss
Treatment - steroids to protect fellow eye
Bilateral in 65% if untreated
Pale disc with diffuse oedema(chalky white
Few, small splinter-shaped haemorrhages
Subsequent optic atrophy

Amaurosis fugax

D,M H,T
Ms symptoms
Painful
painless
Painful
Dramatic sudden onset
Dramatic sudden onset
Acute and progressive
Female
male=female
female
70-80
40-65
20-40

PresentationON NON AION AION

Propotional to VA loss
Disprporttional to VA loss
Disc swelling Chalky
Disc swelling Pale
Normal or papilitis pink
RAPCD
RAPCD
RAPCD
Unilateral then other eye 65 %
Unilateral then other eye 30 %
unilateral
Sever loss
Sever loss
Mild loss VA

Signs

Temporal artery biopsy

MRI
Amplitude decrease
Amplitude decrease
VEP latency increase
Sever leakage
Moderate leakage
FFA mild leakage
ESR elevated CRP markedly raised
ESR elevated
Blood normal
Inferior altitudinal
VF diffuse scotoma

Investigations