Ruptured anterior communicating artery pseudoaneurysm immediately following extended endoscopic transsphenoidal surgery for giant pituitary adenoma: a case report

Intracranial pseudoaneurysm formation after extended transsphenoidal surgery is rare, particularly in the anterior communicating artery. We report a 47-year-old woman with a giant non-functioning pituitary adenoma who underwent extended transsphenoidal surgery with gross-total resection. She developed sudden subarachnoid hemorrhage on the night of surgery. Angiography revealed a 6-mm superiorly directed anterior communicating artery pseudoaneurysm, which was successfully treated with coil embolization following ventricular drainage. Follow-up angiography confirmed complete occlusion. The patient achieved a favorable outcome with a modified Rankin Scale score of 1 at 2 months. This case emphasizes the importance of early vascular imaging and prompt endovascular management.