Long-term outcomes after staged-volume stereotactic radiosurgery for large arteriovenous malformations.
BACKGROUND
Stereotactic radiosurgery is an effective treatment modality for small arteriovenous malformations (AVMs) of the brain. For larger AVMs, the treatment dose is often lowered to reduce potential complications, but this decreases the likelihood of cure. One strategy is to divide large AVMs into smaller anatomic volumes and treat each volume separately.


OBJECTIVE
To prospectively assess the long-term efficacy and complications associated with staged-volume radiosurgical treatment of large, symptomatic AVMs.


METHODS
Eighteen patients with AVMs larger than 15 mL underwent prospective staged-volume radiosurgery over a 13-year period. The median AVM volume was 22.9 mL (range, 15.7-50 mL). Separate anatomic volumes were irradiated at 3- to 9-month intervals (median volume, 10.9 mL; range, 5.3-13.4 mL; median marginal dose, 15 Gy; range, 15-17 Gy). The AVM was divided into 2 volumes in 10 patients, 3 volumes in 5 patients, and 4 volumes in 3 patients. Seven patients underwent retreatment for residual disease.


RESULTS
Actuarial rates of complete angiographic occlusion were 29% and 89% at 5 and 10 years. Five patients (27.8%) had a hemorrhage after radiosurgery. Kaplan-Meier analysis of cumulative hemorrhage rates after treatment were 12%, 18%, 31%, and 31% at 2, 3, 5, and 10 years, respectively. One patient died after a hemorrhage (5.6%).


CONCLUSIONS
Staged-volume radiosurgery for AVMs larger than 15 mL is a viable treatment strategy. The long-term occlusion rate is high, whereas the radiation-related complication rate is low. Hemorrhage during the lag period remains the greatest source of morbidity and mortality.
Department of Neurosurgery, NYU Langone Medical Center, New York, New York, USA. paul.huang@nyumc.org
Paul P
PP
Huang
Stephen C
SC
Rush
Bernadine
B
Donahue
Ashwatha
A
Narayana
Tibor
T
Becske
P Kim
PK
Nelson
Kerry
K
Han
Jafar J
JJ
Jafar
D000293:Adolescent; D000328:Adult; D000368:Aged; D001164:Arteriovenous Fistula / Q000473:pathology / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000473:pathology / Q000601:surgery*; D020300:Intracranial Hemorrhages / Q000453:epidemiology / Q000209:etiology; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology / Q000209:etiology; D016634:Radiosurgery / Q000009:adverse effects; D016896:Treatment Outcome; D055815:Young Adult