Evaluation and Indications for Surgery in Extracranial Cerebrovascular Disease

D URING the past 15 years, the medical profession has been made increasingly aware of the cause and effect relationship between extracranial occlusive cerebrovascular disease and eerebrovaseular strokes. As medical experience increased, exceptions to the rule developed, and diseases simulating extracranial occlusive cerebrovascular disease became apparent. Moreover, there is marked variation in the progress of atheromatous lesions. In some, the atheroma progresses to complete occlusion in a matter of months, while in others, it remains unchanged for years. Individual differences in collateral supply affect the morbidity and the results of any given form of treatment. In the evaluation of the patient with occlusive cerebrovascular disease, a careful history is important. Any reports suggesting transient episodes of paresis or abnormalities of sensation and equilibrium should be considered in detail. 1 A general physical and neurological examination should be performed. Laboratory studies should include a search for diabetes and coagulation or clotting defects. Spinal fluid should be studied for pressure, cell count, and total protein. Electroencephalography, ophthalmodynamometry, and radioactive brain scan are all useful. At the present time, the most important single examination is cerebral angiography2 This technique has passed through various modifications. In our opinion, the most effective method consists in a four-vessel