Prognosis of symptomatic intracranial obstruction of internal carotid artery.

21 patients with intracranial obstruction of an internal carotid artery (ICA) (15 stenoses, 6 occlusions) were studied for angiographic, clinical and prognostic evaluation. Evidence of atheromatous changes and associated risk factors did not significantly differ from age- and sex-matched controls with extracranial ICA disease. No significant difference occurred between matched groups with extra- or intracranial ICA obstruction in functional outcome, delayed strokes, TIAs and death, suggesting that prognosis was more related to age, sex and degree of obstruction than to level of obstruction. 80% intracranial stenosis patients had the worst functional outcome, 30-60% stenosis patients the best, and occlusion patients were intermediate. This corresponded to higher risk of delayed stroke in patients with 80% stenosis. The prognosis was better in patients without evidence of proximal atheromatosis. Only 1 patient with intracranial occlusion suffered delayed homolateral TIAs in which atheromatous embolization from stenosed contralateral ICA was hypothetized.