Surgical aspects of carotid-vertebral insufficiency.

THE ASSOCIATION between obstructive lesions of the extra-cranial portions of the carotid and vertebral arteries and symptoms of cerebro-vascular insufficiency has long been recognized (Todd, 1844), and with the development of reconstructive arterial surgery during the past 20 years it is hardly surprising that a great deal more attention has been focused on the condition. However, in spite of the ease of demonstration of the lesions by arteriography, and the technical competence of vascular surgeons in restoring arterial patency, the role of surgery in the management ofocclusive extra-cranial arterial disease is not yet clearly defined: indeed, it is the subject of much controversy. This state of affairs results from a number of factors-a lack of basic knowledge of the natural history of the untreated disease; the uncertainty of the relationship between a demonstrated carotid or vertebral artery obstruction and ischaemic cerebral symptoms; and, not least, the lack of published results of large, properly controlled clinical trials of surgical versus conservative management 15 years after Eastcott, Pickering & Rob (1954) reported their first experience of carotid endarterectomy. The present paper is concerned chiefly with a consideration of the role of surgery in management, but it is necessary also to review briefly current thinking on the pathology and investigation of extra-cranial cerebro-vascular disease, and to be clear as to what one hopes to achieve by restoration of full arterial patency.