CPT® Code 35508

A carotid-vertebral bypass graft using vein is a surgical procedure designed to create a new pathway for blood flow around a diseased or obstructed segment of the vertebral artery. The vertebral arteries, which are critical for supplying blood to the brain, originate from the brachiocephalic artery on the right side and the subclavian artery on the left side. These arteries travel through the cervical spine, specifically passing through the transverse processes of the C6 to C2 vertebrae, and exit at the base of the skull. The procedure involves both an extracranial segment, which is located between the C2 vertebra and the base of the skull, and an intracranial segment that begins at the atlanto-occipital membrane and continues until the two vertebral arteries converge to form the basilar artery. This vascular structure is essential for supplying blood to the brainstem, cerebellum, and occipital lobes. During the procedure, an incision is made over the obstructed segment of the vertebral artery, allowing for dissection and exposure of the artery. A vein graft, often harvested from the saphenous vein in the leg, is then used to bypass the obstruction. The surgical steps include clamping and incising the vertebral artery, suturing the vein graft to both the vertebral and common carotid arteries, and ensuring proper blood flow through the graft by checking with Doppler ultrasound and evaluating distal pulses. This procedure is critical for restoring adequate blood supply to the brain in cases where the vertebral artery is compromised.