Revascularization in the Acute Stage of Cerebral Ischemia

Abstract

Soon after extra-intracranial bypass surgery was introduced into clinical practice, its potential usefulness in the situation of acute ischemia was suggested. Over the following years, however, the main indication for cerebral revascularization then became chronic brain ischemia, whereas emergency cerebral revascularization remained a matter of controversy. In fact, in contrast to the many thousand patients who underwent extra-intracranial bypass surgery in order to prevent the development of future ischemic events, only a few series have been published on acute cerebral revascularization, with the total number of cases being in the range of little over 100 operated patients. Most of these underwent extraintracranial bypass surgery: some also had acute middle cerebral artery embolectomy [1, 3, 6, 8]. Among the various reasons to explain this obvious discrepancy is the fact that acute brain ischemia is only rarely being seen immediately following its onset. This is necessary to consider any form of surgical intervention. Furthermore, even in those patients who could be operated on within a reasonable time period (6–8 h after the onset of ischemia), the postoperative results which have been reported over the years were not good enough to recommend it as a standard treatment. While overall good results were obtained in two-thirds of the patients, the remaining ones did poorly or died following surgery. With the introduction of new diagnostic possibilities for brain imaging, and also with the use of potentially beneficial treatment modalities to extend the reversibility of brain ischemia, it seems to be justified and also necessary to continue the consideration of emergency cerebral revascularization in the treatment of acute brain ischemia [9]. In this report, summary of our own experience with extra-intracranial bypass surgery in acute brain ischemia will be presented and more recent illustrative case reports will be given to outline the various problems which may arise when emergency revascularization is considered in clinical practice.