Anterior Temporal Approach for Clipping of Upper Basilar Artery Aneurysms: Surgical Techniques and Treatment Outcomes

Abstract

Upper basilar artery (BA) aneurysms, which consist of basilar tip and BA-superior cerebellar artery aneurysms, are challenging to treat with microsurgical clipping. The anterior temporal approach is one surgical approach used to treat aneurysms in this region. Most previous reports on this approach have consisted of unruptured cases. Assessing mostly ruptured cases in this study, we describe the surgical technique, patient characteristics, and surgical outcomes. Twenty-three patients with aneurysms arising from the upper BA who received aneurysm clipping via an anterior temporal approach between December 2015 and January 2019 were retrospectively evaluated. The location of the aneurysms was the basilar tip in 15 patients (65.2%) and the BA-superior cerebellar artery junction in 8 patients (34.8%). Twenty-one patients (91.3%) presented with subarachnoid hemorrhage. Good outcomes (modified Rankin Scale score 0-2) at 3 months were achieved in 55.6% of all patients and in 80% of good-grade patients (World Federation of Neurosurgical Societies grades I-III) and patients with unruptured aneurysms. For patients with subarachnoid hemorrhage, a good outcome was achieved in 75% of good-grade patients. Postoperative transient oculomotor nerve palsy and thalamic infarctions were detected in 7 patients (30.4%) and 2 patients (8.7%), respectively. With appropriate case selection, the anterior temporal approach was effective and safe for clipping of upper BA aneurysms, especially under subarachnoid hemorrhage conditions.