Blood Blister-Like Aneurysm of the Intracranial Internal Carotid Artery Associated With Extracranial Dissection of the Artery

Blood blister-like aneurysms (BBAs) have been described as small aneurysmal bulges, more frequently arising from non-branching sites on the supra-clinoid internal carotid artery (ICA). Their etiology is still controversial. In our case the association of the BBA, presenting with a severe subarachnoid bleeding, and extracranial ipsilateral ICA dissection in a patient with fibromuscular dysplasia, could suggest that both lesions were due to the same pathologic process. The aneurysm was treated in the acute phase with a flow-diverter stent. The patient was discharged symptoms free 24 days later. Control angiography performed 6 months later confirmed persistent aneurysm occlusion.