Microsurgical Strategy for Vertebral Dissecting Aneurysms to Achieve Prevention of Re-bleeding and Preservation of Perforating Branches

Abstract

The authors present an analysis of their experience in treating vertebral artery (VA) dissecting aneurysms (DAs) and proposed a surgical management strategy retrospectively. Between 2008 and 2013, 32 patients with VA-DAs, 20 of whom presented with subarachnoid hemorrhage (SAH), and 12 without SAH, were treated with a direct microsurgical intervention at their institution. The treatment strategy applied to the posterior inferior cerebellar artery (PICA) proximal segment of the dissected site involved proximal occlusion (PO) of the parent artery. Treatment of PICA-involved DA included proximal occlusion with or without trapping, followed by occipital artery (OA)-PICA bypass, and PICA distal-type proximal occlusion just distal to the VA-PICA origin or trapping. The direct VADA treatment was completed within 12 h after the patient was diagnosed with SAH. The OA-PICA anastomosis was performed in 4 patients, and all recipients obtained good flow. In 31 of the patients, angiography revealed complete occlusion of the DA segment. Postoperative modified Rankin Scales measures were 0 in all unruptured cases, 0-2 in 11 cases, and 3-6 in 9 ruptured cases. Treatment-related complications were re-rupture of DAs in 1 case, lateral medullary infarction in 6, lower cranial nerve palsy in 6, and massive cerebellar infarction in 1. Parent artery occlusion of the long segment led to medullary infarction, and trapping procedure of distal VA produced lower cranial nerve injury. Each complication was associated with unfavorable outcomes after treatment. It was superior in preserving perforating arteries of the VA, led to safe revascularization, and prevented the re-rupture of DAs in the direct microsurgery, as compared to internal coil occlusion.