PT - JOURNAL ARTICLE AU - J. Bogousslavsky AU - F. Regli AU - P. Maeder AU - R. Meuli AU - J. Nader TI - The etiology of posterior circulation infarcts AID - 10.1212/WNL.43.8.1528 DP - 1993 Aug 01 TA - Neurology PG - 1528--1528 VI - 43 IP - 8 4099 - http://n.neurology.org/content/43/8/1528.short 4100 - http://n.neurology.org/content/43/8/1528.full SO - Neurology1993 Aug 01; 43 AB - In a prospective study of 70 patients with infarcts in the posterior circulation admitted consecutively to a population-based primary-care center, we assessed infarct location and etiology using magnetic resonance imaging, three-dimensional time-of-flight magnetic resonance angiography, and noninvasive cardiac tests. The brain-stem (mainly the paramedian pons) was the most commonly infarcted site (41/70, 59%), followed by the cerebellum (33/70, 47%). Combined supra- and infratentorial multiple vertebrobasilar infarcts occurred in 11 patients (16%). Overall, 27 patients (39%) had ≥50% stenosis or occlusion of the basilar artery. There were other large-artery lesions in 19 patients (27%), including vertebral (V2-V4) stenosis or occlusion (in seven) and dolichoectatic vertebral/basilar arteries (in 12). Fifteen of the 70 patients had a potential cardiac source of embolism, which coexisted with large-artery disease in more than one-third of the cases. Cerebellar infarct without concomitant brainstem or occipital infarct was associated with cardioembolism (67%), while isolated paramedian pontine or midbrain infarct was associated with basilar artery stenosis (71%), suggesting in situ occlusion of the mouth of the perforators off the stenosed basilar artery. After exclusion of other potential causes of stroke, presumed small-artery disease associated with chronic hypertension remained the likely etiology in only 11 patients (16%), but these infarcts were not associated with any of the classical lacunar syndromes. Our findings emphasize the high frequency of severe intracranial large-artery disease in posterior circulation infarcts.