Transient third cranial nerve palsy after pipeline shield treatment of a ruptured anterior cerebral artery dissecting aneurysm: Case report

Background: Intracranial dissecting aneurysms (IDAs) are rare vascular lesions usually arising from the posterior circulation. The anterior cerebral artery (ACA) is an unusual location for this pathology. Even rarer is the occurrence of a transient de novo third cranial nerve (CN) palsy after flow-diverting device (FDD) treatment of an ACA dissecting aneurysm. Case Description: A middle-aged man with a prior history of hypertension was admitted to our emergency department with severe headache and loss of consciousness after sexual intercourse. Imaging revealed a subarachnoid hemorrhage with stenosis of the left A1 segment of the ACA. Cerebral digital subtraction angiography confirmed a dissecting aneurysm of the left A1 segment. The aneurysm was treated with an FDD (Pipeline Shield). Transient isolated incomplete third CN palsy was documented 12 h after treatment. No evidence of ischemic or hemorrhagic strokes was found. The condition improved after a few days of empiric steroid treatment. Conclusion: An FDD is a suitable alternative for the treatment of a ruptured IDA of the anterior circulation. Some infrequent complications associated with the device, such as de novo cranial neuropathies, are yet to be studied.