SURVIVAL WITH BASILAR ARTERY-OCCLUSION

Basilar artery (BA) occlusion is generally believed to have a high mor tality. A favorable outcome is rarely reported, A consecutive series o f 20 survivors with angiographically proven symptomatic BA occlusion n ot treated with thrombolysis or selected for outcome were analyzed for clinical presentation and neuroradiologic features to find outcome pr edictors. Long-term functional outcome (Rankin scale) was good in 12 ( 60%), moderate in 4 (20%), and poor in 4 (20%) patients who had comple te mid-segmental BA occlusions and bilateral large pontine infarcts. P rominent retrograde collateral supply from the carotids and/or anterog rade from the cerebellar arteries was present in all patients with ade quate angiographic studies (n = 18). BA occlusion was proximal in 12, mid-segmental in 7, and distal in 1 patient. Stroke etiology was consi dered atherothrombotic in 14 (70%), embolic in 2 (10%), and related to migraine in 4 (20%). Clinical outcome following BA occlusion is more heterogenous than usually presumed and influenced by the temporal cour se, length of BA occlusion, availability of collateral circulation, an d extent of brainstem infarction. The etiology of benign BA occlusion is mostly local thrombosis.