Retrograde endovascular recanalization via the ascending cervical artery for non-conical stump vertebral artery occlusion: a case report.

A 61-year-old man presented with a non-tapered occlusion at the origin of the left vertebral artery, with the right vertebral artery failing to join the left vertebral artery to form the basilar artery, and basilar artery tip occlusion. Early antegrade endovascular recanalization attempts with microwires failed to traverse the occlusion at the left vertebral artery origin. Digital subtraction angiography revealed a well-developed left ascending cervical artery communicating with the V3 segment of the left vertebral artery. We adopted a retrograde endovascular recanalization strategy and, with adjunctive balloon angioplasty and stent placement, successfully reestablished patency of the left vertebral artery origin.