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

BACKGROUND: 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. METHODS: 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). RESULTS: 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%. CONCLUSIONS: 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.

Superficial Temporal Artery: Distal Posterior Cerebral Artery Bypass through the Subtemporal Approach: Technical Note and Pilot Surgical Cases.

BACKGROUND: Posterior cerebral artery (PCA) aneurysms are rare and the majority are fusiform in shape. Proximal occlusion of PCA represents a treatment option for these lesions. However, this procedure carries a high risk of ischemic complications. OBJECTIVE: To describe the technique of trapping a fusiform PCA aneurysm and revascularization of the distal PCA using a superficial temporal artery (STA) graft through the same microsurgical approach. METHODS: From September 2012 to October 2014, we retrospectively identified 3 patients harboring a fusiform PCA aneurysm (P2 segment aneurysm) who underwent trapping of the aneurysm and reconstruction of the distal PCA through the same subtemporal approach. We analyzed immediate morbidity, surgical complications, and the patency of the bypass to determine the feasibility of this procedure. RESULTS: All 3 patients underwent successful trapping of the fusiform PCA aneurysm and revascularization of the distal PCA. The origin of P3 segment or posterior temporal artery (PTA) served as recipient arteries. In all 3 cases, adequate blood flow was evident after performing the STA-P3/PTA bypass. None of the patients experienced a new permanent neurological deficit. At 1-year follow-up, the STA-PTA/PCA bypasses remained patent. CONCLUSION: The STA-P3/PTA bypass through the subtemporal approach is a feasible option to maintain blood flow in cases of PCA fusiform aneurysms requiring trapping of the P2 segment.