Set-up Errors Distribution Prediction Model for Pelvic Tumors Radiotherapy of Varian NovalisTX Medical Linear Accelerator Based on Gaussian Mixtures
- VernacularTitle:基于高斯混合模型 Varian NovalisTX 直线加速器盆腔肿瘤放疗摆位误差分布预测模型的构建
- Author:
Min-min QIU
1
;
Jia-jian ZHONG
1
;
Bin OUYANG
1
;
Zhen-hua XIAO
1
;
Yong-jin DENG
1
Author Information
1. Department of Radiation Oncology，The First Affiliated Hospital of Sun Yat-sen University，Guangzhou 510080，China
- Publication Type:Journal Article
- From:
Journal of Sun Yat-sen University(Medical Sciences)
2019;40(2):284-290
- CountryChina
- Language:Chinese
-
Abstract:
【Objective】To constructset-up errors distribution prediction model for pelvic tumors patients radiotherapy of Varian NovalisTX medical linear accelerator.【Methods】The IGRT set-up errors data of 30 pelvic tumor patients after radiotherapywere analyzed，and Gaussian Mixtures was used to construct the errors distribution prediction model and to solve the model parameters.【Results】The set-up errors is mainly concentrated in four central points of μ1~μ4. The coordinates of each central points shows that the offsets of vertical（-3.88~4.28）mm and Longitudinal（-2.41~1.54）mm were larger than that of lateral（-1.85~0.72）mm. The possibility of offsets clustering near μ2 and μ4（0.301，0.310）is greater than μ1 and μ3（0.190，0.196）. And the standard deviation of set- up errors can be up to 5.2 mm.【Conclusions】The Gaussian Mixtures Model made quantitative description and prediction analys is for the set- up errors distribution，which provide references for set-up errors control and planning target expansion of pelvic tumor radiotherapy in the absence of IGRT.
