The feasibility of transposition of the vertebral artery in the lateral approach for lesions situated anterior to the spinal cord around the craniovertebral junction

Abstract

Between 1988 and 2000, the author operated on a total of 47 cases situated around the craniovertebral junction (CVJ) by the lateral approach. The lesions comprised basilar invagination, clivus meningioma, intradural exophytic astrocytoma, neuroma, and osteoblastoma originating in the transverse process of C1, vertebral artery aneurysm, AVM, and dumbbell-shaped neuromas in the high cervical region, all of which were situated anterior, and to variable degrees lateral, to the spinal cord. In some of the above cases that extended both above and below the CVJ, removal of the lesion was greatly facilitated by transposition of the vertebral artery (VA) at the C1/C2 level, as it enabled further forward resection of the occipital condyle and C1/C2 facets, markedly enlarging the operative field in the anterior direction. VA transposition was carried out in 11 out of a total of 47 cases operated by the lateral approach. No complication due to VA transposition was encountered except for one case, in which asymptomatic occlusion of the transposed VA was later found by MRA. VA transposition is considered to be both feasible and useful as an adjunct to the lateral approach.