Persistent nidus blood flow in cerebral arteriovenous malformation after stereotactic radiosurgery: MR imaging assessment.
Stereotactic radiosurgery has become a major force in the treatment of arteriovenous malformations (AVMs) of the brain. After treatment, obliteration of flow through the malformation occurs in 75%-85% of cases within 2 years, assuming the entire AVM nidus can be encompassed by the radiation field. Because the follow-up period is relatively long, a noninvasive means to assess residual transnidus blood flow is desirable. The authors report favorable findings after a comparative analysis of 85 posttreatment magnetic resonance images and 27 follow-up cerebral arteriograms in 34 patients treated with stereotactic radiosurgery. The authors found that transnidus flow can be determined from apparent signal intensity differences between tandem two-dimensional gradient-recalled echo images obtained first without and then with gradient moment nulling (flow compensation), with empirically derived pulse parameters. This method provides a means to monitor the reduction in AVM matrix size and to assess the extent of persistent arteriovenous shunting (ie, blood flow) across the nidus.
Quisling
R G
RG
Department of Radiology, University of Florida Medical Center, Shands Hospital, Gainesville 32610.
Peters
K R
KR
Friedman
W A
WA
Tart
R P
RP
D001921:Brain / Q000473:pathology; D002533:Cerebral Angiography; D002560:Cerebrovascular Circulation; D005500:Follow-Up Studies; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000532:radiotherapy; D008279:Magnetic Resonance Imaging; D013238:Stereotaxic Techniques