Superficial Temporal Artery–Posterior Cerebral Artery Bypass Through Zygomatic Anterior Temporal Approach for Complex Posterior Cerebral Artery Aneurysm

Abstract

Posterior cerebral artery (PCA) aneurysms are rare, and most are giant, dissecting, or fusiform in morphology. Proximal occlusion of the PCA without revascularization causes high risk of ischemic complications. This study aimed to evaluate the safety and validity of using superficial temporal artery (STA)-PCA bypass through zygomatic anterior temporal approach in complex PCA aneurysms. Trapping or resecting of aneurysms and reconstruction of distal PCA through a zygomatic anterior temporal approach were performed in 6 patients from June 2017 to August 2020. Postoperative angiography confirmed obliteration of aneurysms and patency of bypass artery. Neurological function was assessed by the modified Rankin Scale (mRS). Patients were 4 men and 2 women with a mean age of 43.8 years (range, 21-58 years). Subarachnoid hemorrhage occurred in 5 patients. Hunt and Hess grade was IV in 3 patients, III in 2 patients, and I in 1 patient. All PCA aneurysms were treated with trapping or resection of the aneurysms and revascularization of distal PCA. Postoperatively, all aneurysms were eliminated, and no new permanent neurological deficit was found. During follow-up, mRS score of all patients improved: 2 patients had mRS score 0, 1 patient had mRS score 1, 1 patient had mRS score 3, and 2 patients had mRS score 4. Long-term graft patency rate was 100%. STA-PCA bypass appears to be safe and effective for the treatment of complex PCA aneurysms requiring supplementation of blood flow in the area of the PCA. We established a surgical route, allowing the procedure to be done through the zygomatic anterior temporal approach. This approach provides adequate operative field exposure and reduces retraction of temporal lobe.