Unusual computerized tomography appearance of a carotid-cavernous fistula. Case report.

A case of carotid-cavernous fistula characterized by an unusual computerized tomography (CT) pattern is reported. The CT study showed a hyperdense lesion in the right frontoparietal region, and angiography demonstrated an uncommonly large venous network in the same area. After embolization by a detachable balloon technique, these findings gradually resolved. The CT pattern was probably due to the unusually large venous drainage and to the related ischemia of the brain parenchyma.