Gel-foam granuloma in the brain.

A case is recorded in which a large giant cell reaction to gel-foam is noted after its use in neurosurgery. This caused blockage to the flow of cerebrospinal fluid and also thrombosis of superficial vessels of the brain with subsequent infarction. We recognize the value of gel-foam as a haemostatic agent in neurosurgery but wish to warn against its use too close to viable cerebral tissue, as it can induce a marked giant cell granulomatous reaction.