Successful employment of anticoagulants in the treatment of thromboembolic disease outside the central nervous system is well documented and widely accepted. However, only in recent years has clinical support been given to utilization of these drugs when similar vascular lesions occur intracranially, and then only in selected cases in which damage is limited. Recently Siekert, Millikan, and Shick1 listed only five currently accepted indications for use of anticoagulants in cerebrovascular disease.
Encouraging results from the use of anticoagulants in the treatment of the syndromes of intermittent insufficiency of the basilar and carotid arterial systems have been reported in detail by Millikan and Siekert.2,3 These authors subsequently described4 the administration of anticoagulants to patients who had received clinical diagnoses of thrombosis in the vertebral-basilar system. In their series, there was a mortality of 10%, as compared with a mortality of 43% in a similar group of patients not