In answer to the question: "As compared to what?" A progress report on the EC/IC bypass study.
THE DEVASTATION of a major stroke for an individual and his family needs no elaboration for the readers of this journal. To reduce the incidence of this common catastrophe is the goal and preoccupation of many physicians and surgeons. Into the scientific appraisal of therapeutic measures a new element has entered — modern methodology. There is a growing demand by critical members of our profession for convincing accreditation of measures purported to be effective in stroke prevention. As a result medical, and also surgical, means of stroke prophylaxis have been submitted to this type of enquiry by clinical trials. Pitfalls in design, execution and analysis have been encountered in most studies to date, resulting in criticism and cynicism directed at these trials. Both are welcome as they will lead to improvement in methods for further studies. Critics and cynics can hamper, very seriously, the success of an attempt to validate a therapy because if their voices are authoritative they may persuade practitioners and the public that clinical judgement based on experience, well-remembered anecdotes of happy or unfortunate outcomes, or long series of uncontrolled studies with apparently reduced morbidity and mortality are adequate evidence of effective treatment and preferable to "experimenting on people." Trie development of microsurgery followed the pioneering studies of Donaghey and Yasargil who demonstrated that the blood supply of the scalp could be successfully grafted onto that of the brain with safety and patency in humans as well as in the laboratory. 1-* Subsequently, such surgery has been done frequently enough to convince the most critical that it is a procedure of low morbidity and mortality and a large number of neurosurgeons now can perform EC/IC anastomosis with skill and operative success. Patency rates are high and cerebral blood flow studies often demonstrate quantitative improvement in regional cerebral blood flow. Proposed Indications for EC/IC Anastomosis As a sequel to this technical advance there are several potential clinical applications. The first is the prevention of stroke resulting from deliberate surgical occlusion of cerebral arteries. A number of instances are known where a preliminary bypass has permitted deliberate ligation of middle cerebral or internal carotid arteries in dealing with giant aneurysms or tumors at the base of the brain. These observations have demonstrated that despite the small size of the anastomosis between branches of the superficial temporal artery and the middle cerebral artery sufficient blood can be supplied to prevent …