Microsurgical Clipping of a Ruptured Wide-Neck Basilar Tip Aneurysm by an Extended Transsylvian Transcavernous Approach: 2-Dimensional Operative Video.

Basilar tip aneurysms are difficult to treat due to their deep location, proximity to cranial nerves and brainstem, and risk of perforator stroke. A 49-year-old woman presenting to the emergency department with subarachnoid hemorrhage was found to have a wide-neck basilar tip aneurysm measuring 8.6 mm × 5.6 mm × 7.6 mm. The aneurysm had a 4.9-mm wide neck located at the level of the dorsum sellae. Microsurgical clipping was recommended to the patient due to the complexity of the aneurysm neck, the patient's young age, the expertise of the surgical-anesthetic team, treatment durability, and the low risk of recurrence. We used an extended transsylvian transcavernous approach to expose the aneurysm (Video 1). We preferred this anterolateral approach over the more lateral subtemporal transzygomatic approach because of its versatility in providing better visualization of the bilateral posterior cerebral arteries and superior cerebellar arteries. The surgical exposure to the proximal basilar artery was gained by drilling the posterior clinoid process and dorsum sellae. Two titanium clips were applied across the aneurysm neck, and indocyanine green angiography confirmed complete aneurysm obliteration. Protection of critical brainstem perforators was ensured using the rubber-dam technique. The patient tolerated the procedure well with no deficits at the 12-month follow-up. We review the microsurgical nuances of treating complex wide-neck basilar tip aneurysms that are not good candidates for endovascular treatment. Although endovascular tools are favored as the first-line treatment choice for most cerebral aneurysms, microsurgical clipping techniques remain an important tool in the contemporary cerebrovascular neurosurgeon's toolkit..