Development of dose-volume relation model for gamma knife surgery of non-skull base intracranial meningiomas.
OBJECTIVE
To provide a dose-volume relationship for gamma knife surgery (GKS) of non-skull base intracranial meningiomas.


METHODS
The radiologic outcomes of GKS of 82 imaging-defined benign meningiomas located at non-skull base areas were analyzed. A total of 80 patients were included and all underwent treatment with GKS as the first and the only treatment modality. The mean patient age was 55.0 years (range, 26-78) and the mean tumor volume was 5.6 cm(3) (range, 0.5-16.8). On average, 14.6 Gy (range, 10-20) was applied to the 50% isodose surface. The binary logistic regression method was applied to find prognostic factors of signal change (SC) on T(2)-weighted magnetic resonance imaging after GKS.


RESULTS
The actuarial tumor control rate was 91.6% at 5 years. A total of 29 lesions (35.4%) showed newly developed or aggravated SCs. The volume irradiated >or=14 Gy was the only statistically significant (p < .01) prognostic factor of SC. A dose-volume relation model obtained from the cases without SC estimated a 12.2% SC probability.


CONCLUSIONS
This model can be used in GKS to treat small- to medium-size (<9.2 cm(3)) non-skull base meningiomas.
Chung
Hyun-Tai
HT
Department of Neurosurgery, Seoul National University College of Medicine, Seoul, Korea.
Kim
Dong Gyu
DG
Paek
Sun Ha
SH
Jung
Hee-Won
HW
D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D001932:Brain Neoplasms / Q000473:pathology / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D016015:Logistic Models; D008297:Male; D008577:Meningeal Neoplasms / Q000473:pathology / Q000601:surgery*; D008579:Meningioma / Q000473:pathology / Q000601:surgery*; D008875:Middle Aged; D011336:Probability; D011379:Prognosis; D016634:Radiosurgery / Q000295:instrumentation / Q000379:methods*; D011879:Radiotherapy Dosage; D047368:Tumor Burden