Clinical and Radiological Prognostic Factors in Cerebral Arteriovenous Malformations

Abstract

Progress in microsurgery has meant that operative treatment of arteriovenous malformations (AVMs) has nowadays become to a high degree safe. In consequence there is a clear indication for surgery in the majority of these lesions, whereas some 25 years ago conservative treatment was recommended in 85% of all cases [10]. Thus, progress in surgical techniques has abrogated a lot of restrictions to surgery of AVMs. However, this new surgical freedom is increasingly offset by the progress made in endovascular techniques, which are not limited to lesions not amenable to surgery but are becoming established as an alternative form of treatment or even the treatment of choice in malformations well accessible to the surgeon. These developments require careful consideration during decision making, which should be based on empirical data allowing the best assessment of the prognosis in each individual case. Since the term AVM designates relatively heterogeneous lesion, mere comparison of different series of surgically treated or surgically vs. endovascularly treated cases provides only more or less anecdotal information. This is the reason why grading systems have been published. In a previous paper [3] we discussed the value and practicability of the systems of Luessenhop and Genarelli [5], Spetzler and Martin [9], and Shi and Chen [8]. We arrived at the conclusion that, although the system of Spetzler and Martin has some advantages, strictly speaking all these grading systems are rather arbitrary and have a low accuracy in predicting the outcome of surgery of AVMs.