Three weeks after an automobile accident, a 35-year-old man experienced left throat and neck pain, numbness of the left face and tongue, dysphagia, left arm pain and weakness, and left miosis. At age 27, he had suffered an aneurysmal subarachnoid hemorrhage. Angiography at that time had also demonstrated a fenestration of the left intracranial vertebral artery. At the time of the second presentation, angiography showed that one of the limbs of the fenestration had become occluded. Although the vast majority of intracranial arterial fenestrations are asymptomatic, occlusion of one of the limbs of a fenestration may be the cause of stroke.