Which is a more appropriate recipient for posterior circulation bypass surgery: V3 or V2? Differences in underlying disease and lesion sites between extracranial vertebral artery dissection and atherosclerotic changes. Illustrative cases.

Background: Revascularization for extracranial vertebral artery dissection or vertebral artery atherosclerotic occlusive lesions caused by vertebrobasilar insufficiency or posterior circulation infarction is relatively rare. When bypassing the cervical external carotid artery (ECA) or common carotid artery (CCA) using a radial artery (RA) or saphenous vein (SV) graft, it is difficult to determine whether the recipient site should be the V2 or V3 portion.

Observations: In case 1, cervical ECA-RA-V3 bypass was performed for bilateral extracranial vertebral artery dissection with the onset of ischemia, and cervical CCA-SV-V3 bypass was added 12 days later. Nine years after surgery, the bilateral vertebral artery dissection had improved, and the patient still had a patent bypass. In case 2, cervical ECA-RA-V2 bypass was performed for arteriosclerotic bilateral extracranial vertebral artery occlusion. The bypass was patent 5 years after surgery. The postoperative course was uneventful in both patients.

Lessons: The authors present cases of posterior fossa revascularization using the vertebral artery V3 and V2 portions via skull base surgery and note that it is important to consider each patient's individual characteristics when selecting the V3 or V2 portion.