A study of dose homogeneity in radiosurgery planning for vestibular schwannomas
Tang Xuqun
Pan Li
Yan Meirong
Wu Hanfeng
Abstract：Objective To investigate the factors influencing dose homogeneity index(DHI)in the radiosurgery planning for vestibular schwannoma and a simpler alternative calculation method for DHI.Methods The gamma knife treatment plan of 301 patients with vestibular schwannoma were analyzed retrospectively,298 of them were treated with classical single treatment,and 3 with continuous hypofractionation.According to the International Commission on Radiation Units and Measurements(ICRU)-83 standard,the planned HI was calculated and the factors that may affect the HI were evaluated.The dose coefficient of variation(DCV)of the target area was calculated to evaluate its feasibility as an alternative to HI.Results The mean HI of the treatment program was 0.60±0.08.Univariate analysis showed that all planned parameters were statistically significantly associated with HI except for peripheral dose(all P<0.05).Multivariate analysis showed that prescription dose line,coverage,selectivity,gradient index and target volume were statistically significant correlated factors(all P<0.05).DCV could be well-fitted to the HI.Conclusions HI is closely related to other parameters of treatment planning.DCV can be utilized as an alternative and convenient method for evaluation of HI.
Keywords：vestibular schwannomaGamma Knifehomogeneity index
Publication Date：2024-03-20
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：5( 153-157 )