Surgical approach to the whole length of the vertebral artery with special reference to the third portion.

A lateral route between the SCM and the lateral border of the internal jugular vein is defined from an anatomical study for exposure of the VA. It offers the simplest route for controlling any part or the whole length of the VA, including its intracranial portion. Surgical indications are discussed on the basis of our experience in eight cases with, in all cases, control of the VA in its third segment between C2 and the foramen magnum. Arteriovenous malformations are the most frequent indications; two cases were treated by direct approach and one by exclusion and anastomosis between the internal carotid artery and the vertebral artery at C1-C2. TUmours of the lateral cervical space (one haemangiopericytoma and one jugular glomus tumour) or of the posterior fossa extruding out of the foramen magnum or the jugular foramen (one meningioma) may require control of the VA. Traumatic lesions (one case) or compression by an osteophytic spur are also indications for this approach. Wall lesions of the VA (aneurysm or stenosis) are best treated by exclusion and anastomosis between either the carotid or the subclavian artery and the vertebral artery at C1-C2 level. One case of aneurysmal dysplasia was cured by anastomosis between the subclavian artery and the vertebral artery at C1-C2 with a saphenous vein graft and clipping of the VA proximal to the by-pass. Radiological examinations are fundamental for diagnosis, treatment when embolization is necessary, and choice of surgical treatment, according to the importance of the contralateral VA and the medullary branches.