Dissecting Aneurysm of the Middle Cerebral Artery Anterior Temporal Branch: A Case Report

Introduction: A nontraumatic dissecting aneurysm of the middle cerebral artery (MCA) is extremely rare. Most are found on the main trunk of the MCA or rarely on the M2 or M3 segments. Spontaneous dissection of the anterior temporal branch of the MCA has not been reported before. Case Report: A 23-year-old woman was admitted to our department 4 days after a subarachnoid hemorrhage. Her Yasargil grade was 2a. On computerized tomography there was blood in the right sylvian fissure and anterior temporal lobe. The patient had no previous trauma history and no concomitant illness. DSA revealed a dissecting aneurysm originating from middle cerebral artery M1 segment proximal to the anterior temporal branch. During the operation the dissecting aneurysm was noticed on the anterior temporal artery. The main M1 segment was intact. The dissection was arising just from the proximal segment of the anterior temporal artery 2 mm distal from the origination of the M1 segment. The anterior temporal artery was clipped just proximal to the aneurysm and the dissecting part was removed successfully. The postoperative course was uneventful and the patient was discharged on the seventh postoperative day. Control DSA revealed complete removal of the aneurysm. The patient is symptom-free 1 year after the surgery. Conclusion: Dissecting aneurysms of the MCA should be aggressively treated in order to prevent a new hemorrhage or stroke. Preoperative DSA images are very important for precision and convenient treatment options. Endovascular surgery might be a good option in particular cases.