Transient focal neurologic episodes in cerebral amyloid angiopathy
Cerebral amyloid angiopathy is a degenerative condition in which amyloid is deposited in cerebral vessels, making them friable and at risk of bleeding. Most patients have no symptoms whatsoever, and the diagnosis is made by magnetic resonance imaging. Small microbleeds are common, but lobar intraparenchymal hemorrhage is the most feared complication.
Transient focal neurologic episodes, sometimes termed “amyloid spells,” are recurrent, stereotyped neurologic events that are spurred by cortical superficial siderosis (deposition of iron). Unfortunately, these events are difficult to characterize by their clinical morphology. The events can involve the visual, motor, and sensory pathways with both positive and negative symptoms, making the diagnosis difficult without imaging. These events may precede a symptomatic intraparenchymal hemorrhage, offering a unique window to reconsider the decision to continue an antiplatelet or anticoagulant drug. 57,58