Microsurgical Technique for Basilar Apex Aneurysm Clipping: Two-Dimensional Video

Abstract

We present the case of a 57-year-old female with hypertension, current smoker status, and recent headaches. Imaging studies showed an unruptured 8-mm basilar apex wide neck aneurysm located 4 mm above posterior clinoid (Figure 1) with a 3-mm anterior communicant artery aneurysm. No contraindications were encountered for endovascular treatment, although after we evaluated endovascular and surgical options, surgical clipping was considered also a safe and favorable option based on anterior projection of aneurysm, height of the basilar artery bifurcation, small and elongated posterior communicant artery, and available space between posterior clinoid and basilar artery (4 mm). The presence of a second aneurysm increased the patient's interest in a more definitive treatment, as we mentioned the possibility of its treatment if considered safe intraoperatively. A cranio-orbito-zygomatic craniotomy, anterior clinoidectomy, and sylvian fissure dissection was performed with electrophysiology monitoring. The exposure was enhanced by sphenoparietal sinus ligation, and the anterior clinoidectomy allowed working spaces at optic-carotid and carotid-oculomotor spaces for Liliequist membrane dissection, without need for posterior clinoid removal (Figure 2). Brief temporary clipping at basilar trunk below superior cerebellar arteries at perforating free zone was performed. Two clips were applied, obliterating adequately the aneurysm respecting perforating vessels. After the basilar apex aneurysm clipping, we proceeded in a standard fashion to clip the additional anterior communicant artery aneurysm. Micro-Doppler and intraoperative angiogram confirmed aneurysm exclusion and patent parent vessels (Video 1). The patient developed minimal ptosis due to partial right oculomotor nerve palsy that recovered completely in 2 weeks; otherwise, her neurologic exam was normal. At 1-year follow up, computed tomography angiography showed complete aneurysm exclusion.

Keywords: Basilar apex aneurysm; Cranio-orbito-zygomatic craniotomy; Microsurgical clipping.