Intracranial Stenosis – ICAD and Moyamoya

ICAD (Intracranial Atherosclerotic Disease)

• Also referred to as ICAS (Intracranial Atherosclerotic Stenosis)

Trials

WASID

• RCT aspirin vs Warfarin

• No benefit of warfarin

• More bleeds with warfarin

CLAIR

• RCT Clopidogrel + Aspirin VS Aspirin

• Recently symptomatic ICAS

• Outcome was TCD microemboli – these were lower at day 2 and 7

• Not powered to look at stroke outcomes, but appeared lower

SAMMPRIS

• Medical management (including DAPT) VS Medical Mx + Stent

• 30 day stroke or death was 14.7% in stenting group vs 5.8% in Medical management

Moyamoya

• Progressive stenosis pf the intracranial internal carotid arteries and their proximal branches

• Moyamoya disease – Idiopathic

• Moyamoya syndrome – Associated with another condition

Epidemiology

• More common in Asia

o Japan 3/100,000

o Europe 0.3/100,000

o USA 0.1/100,000

• Age peaks: 5 years and 40 years

• Male:Female 1:2

• Associated conditions (i.e. Moyamoya syndrome)

o Sickle cell disease

o NF1

o Cranial irradiation

o Down’s syndrome

Clinical presentation

• Ischaemic stroke 50-75%

• TIA 50-75%

• Haemorrhage 10-40%

• Headache

• Seizures

• Cognitive changes

• Chorea

• Morning glory optic disc

• Haemorrhage

o Intraventricular

o Intraparenchymal (often basal ganglia)

o Subarachnoid

Prognosis

~2/3 progress over 5 years without treatment

Treatment

• Avoid hypotension

• Anti-platelet generally recommended (although no trial evidence)

• Calcium channel blockers for headache (with caution to avoid hypotension

• Surgery

o Direct revalcularisation – external carotid branch (e.g. superficial temporal artery) anastomosis to cortical artery

o Indirect – tissue perfused by external carotid (e.g. dura or muscle) is place on the brain and allowed to anastamose over time.

References:

Moyamoya disease NEJM Review 2009