Stroke & Vascular Disorders
Antiphospholipid antibody syndrome
Jun. 30, 2022
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German ophthalmologist Friedrich Wilhelm Ernst Albrecht von Gräfe (often Anglicized to Graefe; 1828-1870) described von Graefe sign, a dynamic phenomenon in which the descent of the eyelid is retarded during eye movements from primary position to downgaze. (Courtesy of the U.S. National Library of Medicine. Public domain.)