Role of Preoperative Embolization with NBCA(n-Butyl Cyanoacrylate) in the Surgical Management of Cerebral Arteriovenous Malformations

Chung, Young Seob; Oh, Chang Wan; Han, Dae Hee

Abstract

The medical and radiological records of 66 patients who underwent surgical resection of supratentorial arteriovenous malformations(AVM's) between January 1989 and July 1994 were retrospectively reviewed. Preoperative embolization of these AVM's with N-butyl cyanoacrylate(NBCA) was performed in 23 patients, and in the other 43, the AVM's were removed without embolization. The mean follow-up period was 23.5 months. To evaluate the effects of preoperative embolization on the surgical management of AVM's, the two groups of patients were compared. In the group which underwent preoperative embolization, the mean diameter of the AVM's was larger(4.8cm vs 3.5cm, p=0.0024) and the mean Spetzler-Martin grade of the AVM's was higher(3.3 vs 2.4, p=0.0012) than in the nonembolized group. In the embolized group, operation time was a little longer, though this was not statistically significant, and the amount of transfusion required during surgery was greater with statistical significance(p=0.0067). Multivariate analysis, however, demonstrated that both these factors correlated only with lesion size(p=0.0038, p=0.0099) regardless of grade and embolization. A greater amount of transfusion was required because AVM's in the embolized group were larger. Feeder vessels and a nidus embolized with NBCA were so easily distinguished, compressed, and cut without bleeding that surgical resection was facilitated. Embolization caused one immediate hemorrhage and four neurological complications: permanent deficits in one and transient deficits in three. It was therefore concluded that preoperative embolization with NBCA made surgical resection of larger and higher grade AVM's as effective as surgical removal of those which were smaller and of lower grade, with no significant difference in operation time and surgical outcome; embolization appeared to have no effect on the amount of transfusion required, and was very safe.