Intracranial arteriovenous malformations treated with linear accelerator-based conformal radiosurgery: clinical outcome and prediction of obliteration.
BACKGROUND
Little is written about the clinical outcome and predictor factors of obliteration and treatment success in patients with intracranial AVMs treated with LINAC-based conformal radiosurgery in Mexican institutions.


METHODS
We analyzed 40 patients with intracranial AVMs with a mean follow-up of 29 (range, 23-34) months. Seven AVMs (17.5%) had a volume <1 cm(3); 10 (25%), 1 to 4 cm(3); 13 (32.5%), 4.1 to 10 cm(3); and 10 (25%), >10 cm(3). The mean prescription dose was 15.4 Gy. Twenty-six patients (68%) presented hemorrhage before treatment; 4 (10%), chronic headache; 14 (35%), seizures; and 3(8%), neurologic deficit.


RESULTS
Seven patients (17.5%) underwent objective clinical improvement. Thirty patients (75%) remained without clinical changes. Three patients (7.5%) developed edema and 1 (2.5%) had a rebleeding after treatment. Twenty-five patients (63%) presented complete obliteration of the AVM. A successful treatment (obliteration without a new deficit) was obtained in 23 (58%) of the cases. The percentage of obliteration was in <1 cm(3) (86%), 1 to 4 cm(3) (80%), 4.1 to 10 cm(3) (54%), and >10 cm(3) (40%), without a significant difference between groups (P = .1). Patients with RBAS of <or=1.9 had an obliteration of 79% and, those with >1.9, 48%; the successful treatment in the former resulted in 79% and, in the latter, 38% (P = .08 and P = .02, respectively).


CONCLUSIONS
The clinical outcome was similar to other series. The RBAS seems to be a good predictor of obliteration and successful treatment in patients with AVMs treated with LINAC-based conformal radiosurgery.
Moreno-Jiménez
Sergio
S
Neurosurgery, National Institute of Neurology and Neurosurgery, Mexico City, C.P. 14269, México DF. ser_radioneurocirugia@yahoo.com.mx <ser_radioneurocirugia@yahoo.com.mx>
Celis
Miguel Angel
MA
Lárraga-Gutiérrez
José Manuel
JM
de Jesús Suárez-Campos
José
J
García-Garduño
Amanda
A
Hernández-Bojórquez
Mariana
M
D000293:Adolescent; D000328:Adult; D001929:Brain Edema / Q000453:epidemiology / Q000503:physiopathology; D002536:Cerebral Arteries / Q000002:abnormalities* / Q000503:physiopathology / Q000601:surgery*; D002648:Child; D005260:Female; D006261:Headache / Q000209:etiology; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology* / Q000503:physiopathology; D019106:Postoperative Hemorrhage / Q000453:epidemiology / Q000503:physiopathology; D011829:Radiation Dosage; D016634:Radiosurgery / Q000592:standards / Q000706:statistics & numerical data* / Q000639:trends*; D055502:Secondary Prevention; D012640:Seizures / Q000209:etiology; D016896:Treatment Outcome