Lacunar Infarction Associated With Intracranial Venous Hypertension

Lacunar infarcts constitute a subtype of stroke with a diameter of less than 15 mm manifested by the presence of lacunar syndromes. The ischemic lesion in lacunar infarcts may often be caused by occlusion of a single, small perforating artery. However it is known that lacunar infarcts may also be associated with large artery disease, cardioembolism, and other less frequently encountered causes including antiphospholipidic syndrome, amyloid angiopathy, infectious arteritis, and inflammatory arteritis. A lacunar infarct of venous type is unusual. A 72-year-old woman presented with left hemiparesis that developed within the last several hours. She also had mild dementia for several months. Radiological examination showed a white matter lacunar infarct evidenced by restricted diffusion and T2 abnormality and dural arteriovenous fistula of the superior sagittal sinus. Because the segment distal to the fistula was occluded the fistulous flow was drained away from the sinus via retrograde flow through the cortical veins, which leaded to intracranial venous hypertension. The findings in our patient suggest that venous causes should also be considered in the differential diagnosis of lacunar infarcts.