[Fatal Acute Brain Swelling after Clipping of Unruptured Anterior Communicating Aneurysm: A Case Report].

There have been few reports about acute brain swelling caused by unruptured aneurysm surgery. We report a case of fatal acute brain swelling after clipping of an unruptured anterior communicating artery aneurysm following lung cancer surgery. A 65-year-old man underwent aneurysm neck clipping for an unruptured anterior communicating artery aneurysm by interhemispheric approach 35 days after curative resection of lung cancer. Immediately after the operation, his recovery from anesthesia was prolonged and anisocoria developed. Therefore, we performed emergent reoperation and encountered acute brain swelling necessitating decompressive craniectomy. Despite intensive medication including barbiturate therapy, the patient died 4 days after the operation. Autopsy revealed that brain swelling was caused by congestion with thrombus in the superior sagittal sinus apart from the site of the craniotomy. Fatal sinus thrombosis might develop during neurosurgical operation in patients with cancer.