Study design: This study retrospectively analyzed the outcome of unilateral vertebral artery ligation during cervical spine surgery.
Objectives: To examine the influence of unilateral vertebral artery ligation on the function of brain and spinal cord.
Summary of background data: There was little published information about the outcome of a vertebral artery ligation except for several reports from the field of neurosurgery.
Methods: Unilateral vertebral artery ligation was used in 15 patients with cervical tumors of the spine or the spinal cord (age range, 13-71 years; nine male patients and six female). The authors ligated the involved vertebral artery only when the tumor appeared on the minor or equal diameter artery side measured by pre-operative angiogram. The patient's condition was examined regarding signs of dysfunction of the brain stem, the cerebellum, or the spinal cord.
Results: Preoperative angiogram showed that the involved vertebral artery had a smaller diameter in four patients and had an equal diameter in 11 patients compared with the one not involved. The involved vertebral artery was severed at single site in four patients and was resected between two distant sites of ligation in 11 patients. Examination after surgery of the patient's condition (follow-up periods ranged from 10 months to 7 years) revealed that unilateral vertebral artery ligation did not provoke any symptoms of damage resulting from ischemia of the brain stem, the cerebellum, or the spinal cord.
Conclusion: A vertebral artery could be ligated uneventfully when the diameter of the vertebral artery was not larger than the one not involved. Where vertebral artery ligation could not be avoided, it should be confirmed by preoperative angiogram that the other vertebral artery is large enough and that simultaneous occlusion testing of the involved vertebral artery is uneventful.