Comparative Study of Angiography and Magnetic Resonance Image in Verifying Obliteration of Arteriovenous Malformation after Gamma Knife Radiosurgery

ABSTRACT

OBJECTIVE: The purpose of this study is that magnetic resonance(MR) imaging can substitute for conventional angiography in verifying obliteration of arteriovenous malformation(AVM) after Gamma Knife radiosurgery. METHODS: Among the patients of AVM treated with Gamma Knife between 1992 and 1997, all of 40 patients who had been followed up more than 2 years(range 24-101 months) had no AVM on follow-up MR images. Follow-up imaging was performed every 6 months or when clinically warranted. Conventional angiography was performed when the AVM was no longer seen on MR images. RESULTS: Among 40 patients who had shown total obliteration on MR images, thirty one patients(77.5%) showed complete obliteration of the lesion on angiography. However, subtotal obliteration was shown in five patients(12.5%) and partial obliteration in four patients(10.0%). CONCLUSION: The conventional angiography is absolutely needed for verifying obliteration of AVMs and to eliminate the misunderstanding of follow-up MR images.