Dose distribution and shrinkage of acoustic neurinomas 2 years after Gamma Knife treatment.
To examine the relationship between dose distribution and tumor shrinkage of acoustic neurinomas, correlation coefficients between distribution probabilities of some dose areas and residual tumor ratios of 21 cases were studied at 2 years. Approximating a dose-volume histogram to beta-distribution, two essential dose areas for tumor control were extracted: a dose area from 14.2 to 24.7 Gy contributed to tumor shrinkage, whereas a dose area from 27.3 to 29.4 Gy was contraindicated. Given that there are at least two different dose areas with reverse characters, a formula with two opposing logistic components is proposed to predict tumor control. With this formula, Gamma Knife treatment of acoustic neurinomas may be optimized.
Nagano
H
H
Department of Radiology, Yokohama Rosai Hospital, Japan.
Tanohata
K
K
Kato
E
E
Nakayama
S
S
Fujino
H
H
Matsubara
S
S
D000328:Adult; D000368:Aged; D003390:Cranial Nerve Neoplasms / Q000601:surgery*; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D009464:Neuroma, Acoustic / Q000601:surgery*; D011829:Radiation Dosage; D016896:Treatment Outcome