Time-Staged Gamma Knife Stereotactic Radiosurgery for Large Cerebral Arteriovenous Malformations: A Preliminary Report.
OBJECTIVE
We retrospectively analyzed our experience with time-staged gamma knife stereotactic radiosurgery (GKS) in treating large arteriovenous malformation(AVM)s;≥ 10 cm3).


METHODS
Forty-five patients who underwent time-staged GKS (2-stage, n = 37;3-stage,n = 8) between March 1998 and December 2011 were included. The mean volume treated was 20.42±6.29 cm3 (range, 10.20-38.50 cm3). Obliteration rates of AVMs and the associated complications after GKS were evaluated.


RESULTS
Mean AVM volume (and median marginal dose) at each GKS session in the 37 patients who underwent 2-stage GKS was 19.67±6.08 cm3 (13 Gy) at session 1 and 6.97±6.92 cm3 (17 Gy) at session 2. The median interval period was 39 months. After follow-up period of 37 months, the complete obliteration rate was 64.9%. The mean AVM volume (and median marginal dose) at each GKS session in the 8 patients who underwent 3-stage GKS was 23.90±6.50 cm3 (12.25 Gy), 19.43±7.46 cm3 (13.5 Gy), 7.48±6.86 cm3 (15.5 Gy) at session 1, 2, and 3, respectively. The median interval duration between each GKS session was 37.5 and 38 months, respectively. After a median follow-up period of 47.5 months, 5 patients (62.5%) achieved complete obliteration. Postradiosurgical hemorrhage developed in 5 patients (11.1%) including one case of major bleeding and 4 cases of minor bleeding. No patient suffered from clinically symptomatic radiation necrosis following radiation.


CONCLUSIONS
Time-staged GKS could be an effective and safe treatment option in the management of large AVMs.
Department of Neurosurgery, Soonchunhyang University Hospital, Seoul, Republic of Korea.
Hye Ran
HR
Park
Department of Neurosurgery, Seoul National University Hospital, Seoul, Republic of Korea.
Jae Meen
JM
Lee
Department of Neurosurgery, Seoul National University Hospital, Seoul, Republic of Korea.
Jin Wook
JW
Kim
Department of Neurosurgery, Seoul National University Bundang Hospital, Seoul, Republic of Korea.
Jung-Ho
JH
Han
Department of Neurosurgery, Seoul National University Hospital, Seoul, Republic of Korea.
Hyun-Tai
HT
Chung
Department of Radiology, Seoul National University Hospital, Seoul, Republic of Korea.
Moon Hee
MH
Han
Department of Neurosurgery, Seoul National University Hospital, Seoul, Republic of Korea.
Dong Gyu
DG
Kim
Department of Neurosurgery, Seoul National University Hospital, Seoul, Republic of Korea.
Sun Ha
SH
Paek
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D016634:Radiosurgery / Q000379:methods*; D012189:Retrospective Studies; D016896:Treatment Outcome; D055815:Young Adult