[Transient cortical blindness and convulsion mimicking a hemorrhagic complication during embolization of the cerebellar AVM].

We report a case of transient cortical blindness and convulsions during embolization of the cerebellar AVM. A 29-year-old man was admitted to our hospital with subarachnoid hemorrhage. Cerebral angiography showed the right cerebellar AVM fed by the right superior cerebellar artery. Preoperative embolization of the AVM was performed. During embolization, the patient lost consciousness suddenly and appeared to be in a decerebrate posture. About 15 minutes later, the patient came around and complained of total blindness. Cerebral angiography revealed the disappearance of the aneurysm and AVM. There were no abnormal findings in the vertebrobasilar system. Computed tomography obtained just after the procedure, showed considerable contrast enhancement of the occipital lobes. Two hours later, a repeat computed tomography showed clearance of contrast enhancement. Magnetic resonance imaging obtained 12 hours after the procedure, showed no evidence of infarction in the occipital lobes. Two days after, the patient's sight gradually returned. Seven days after the procedure, the patient recovered completely. We speculated that these clinical features might be convulsions due to contrast material. In the reported cases, convulsions and transient cortical blindness due to non-ionic low osmolar contrast materials is a rare complication. This case suggested disruption of the blood-brain barrier demonstrated by the computed tomography appearance of contrast enhancement in the occipital lobes.