Multiple intracranial aneurysms following radiation therapy for nasopharyngeal carcinoma

A 30-year-old male presented to the neurosurgical emergency with sudden onset severe headache, nausea, and vomiting. A computed tomography scan showed subarachnoid hemorrhage and a subsequent four vessel angiogram showed six cerebral aneurysms (predominantly fusiform) involving both the anterior and posterior circulations, all on the left side. The patient had received 60 Gy external beam radiotherapy for left nasopharyngeal carcinoma 8 years back. The middle cerebral artery aneurysm was clipped, while the internal carotid artery and the two posterior cerebral artery aneurysms were wrapped. The patient was discharged uneventfully and is asymptomatic at follow-up 6 months later. The effects of radiation on cerebral vasculature are well-documented. Radiation-induced vasculopathy generally presents as occlusion/stenosis of cerebral vessels and aneurysms are rare. Only 46 cases of radiation-induced aneurysms have been reported previously. Just seven of these had multiple aneurysms and only one case had as many as six aneurysms.