Fusiform aneurysm of the middle cerebral artery

Introduction. The main objective of the treatment of intracranial aneurysms is to isolate them from the cerebral blood circulation. A fusiform aneurysm, because of its shape, cannot be treated using the usual techniques and usually requires techniques of arterial reconstruction and revascularization using by-pass. Currently it is possible to find the vascular territories with the greatest risk of causing neurological defects and where revascularization is necessary. Case report. A 20 year old man with no previous history of illness who had several transient ischaemic episodes. Emergency laboratory tests, ECG and plain chest Xray were all normal. Imaging investigations showed the presence of a fusiform aneurysm of the anterosuperior division of the right middle cerebral artery. No associated systemic disease was detected. Wada's test showed the vascular territory with the greatest risk of neurological deficit. Extra-intra cranial by-pass was done from the right superficial temporal artery to the distal portion of the anteriorsuperior branch of this artery. The operation was done using a right pterion approach with dissection of the superficial temporal artery, and the aneurysm, trapping and termino-lateral anastomosis. Cerebral protectors and mild hypothermia were used during the operation. The post-operative course was uneventful. Anatomo-pathological diagnosis was of an atherosclerotic fusiform aneurysm with osseous and chondroid metaplasia. After six months follow-up the patient remains asymptomatic. Discussion and conclusions. Treatment of fusiform cerebral aneurysms is complex and usually requires procedures for cerebral revascularization. Correct pre-operative evaluation is essential to identify the vascular territory with the greatest risk of causing neurological deficit. Wada's test is useful for this, since it permits selective evaluation of the different vascular territories safely and quickly. High or low flow by-pass of these territories prevents cerebral ischaemia and permits the treatment Of choice for these aneurysms.