Lacunar Stroke: Relationship Between Atypical Etiology and Infarct Size?

To the Editor.  —A number of recent publications^1-3 have emphasized that small deep cerebral infarcts can be caused by a variety of etiologic factors including cardioembolism and large vessel occlusion. This has led some authors to conclude that the "lacune hypothesis," which suggests that lacunes are caused by lesions involving small perforating brain arteries, is a "fallacy"¹ and that the term lacunar "should be evicted from the bedside."²In their recent article,⁴ Waterston and colleagues provide further evidence that the cause of small deep cerebral infarcts is diverse. In reviewing their study, as well as other reports of patients with lacunes of "atypical etiology,"⁵ it appears that a high percentage of these patients have unusually large lacunes.Most lacunes are only 2 to 3 mm in maximal diameter,^6,7 and Fisher⁷ believed that lacunes greater than 10 mm in diameter should be designated as giant