Intracranial extravasation of contrast medium during carotid angiography.

The results of 5184 carotid angiograms were reviewed and five cases of intracranial extravasation of contrast medium were found. In two cases an aneurysm ruptured during angiography and extravasation into the subarachnoid space was seen. In one case medium leaked from an angiomatous malformation into the subdural space. The fourth case was a patient who had suffered closed head trauma. Here extravasation was seen deep within the brain. The fifth case illustrates two forms which extravasation from meningeal arteries may take. The incidence and prognostic significance of this finding in different conditions are discussed.