Inadvertent foreign body embolization in diagnostic and therapeutic cerebral angiography.

BACKGROUND AND PURPOSE Inadvertent foreign body embolization is a rarely diagnosed and neglected complication of cerebral angiography that has not been studied systematically. METHODS We undertook a comprehensive 5-year retrospective study of all available postmortem cases of postangiographic neurologic complications, as well as a comprehensive histologic examination of all surgically resected central nervous system arteriovenous malformations, at our institution. RESULTS Among the autopsy series, we found 3 patients for whom cerebral infarction, sometimes catastrophic, is attributable to inadvertent cotton fiber, Gelfoam, or polyvinyl alcohol particulate emboli during cerebral angiography. All cases described had concurrent atherosclerotic vascular disease. Particulate embolization, which is usually cotton fiber, is present in as many as 25% of resected arteriovenous malformations: the risk of finding such emboli is in part dependent on a history of prior interventional (as opposed to diagnostic) angiographic procedures. It is not surprising that the amount of tissue examined also increases the risk of finding such emboli. CONCLUSIONS Unintentional foreign body emboli remain common in modern angiographic practice and are probably underappreciated clinically. Although such emboli are usually asymptomatic, they can be clinically devastating, and a high index of suspicion is required for diagnosis. Foreign body emboli should be included in the differential diagnosis of postangiographic ischemia or infarction.