title: Are strokes more likely to result from severe carotid atherosclerotic stenoses? If not, why not?
abstract: The authors studied by carotid duplex ultrasonography 478 unselected elderly patients (age sixty to one hundred one years, mean 82 +/- 8), in their long-term health care facility. Of these, 108 had previously experienced strokes owing to atherothrombotic brain infarcts, documented by a neurologist, and 370 had not. The degree of extracranial internal or common carotid narrowing in these patients was classified by standard Vmax Doppler criteria as 0-40%, 40-80%, and 80-100% luminal diameter reduction. The authors found that 87% of the patients had little or no carotid stenosis (0-40% luminal diameter reduction). Nevertheless, 79% of the previous strokes had occurred in these patients, and the incidence of strokes in this group was 21%. Severe, but not mild or moderate, degrees of carotid obstruction (80-100% luminal diameter reduction) were associated with a 100% stroke incidence. The authors conclude that strokes most commonly result from causes other than ischemia due to in situ severe extracranial internal or common carotid stenosis or occlusion.
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001161:Arteriosclerosis / Q000150:complications* / Q000175:diagnosis / Q000473:pathology; D002340:Carotid Artery Diseases / Q000150:complications* / Q000175:diagnosis / Q000473:pathology; D002544:Cerebral Infarction / Q000150:complications; D002561:Cerebrovascular Disorders / Q000209:etiology*; D003251:Constriction, Pathologic; D005260:Female; D006801:Humans; D002542:Intracranial Embolism and Thrombosis / Q000150:complications; D008297:Male; D008875:Middle Aged; D014463:Ultrasonography