Preliminary Research On Design And Verification Of After-loading Brachytherapy Simulation System

Cervical carcinoma is the most common malignant tumor of women, which is the number one of malignant tumors of women in China. Combination of external radiotherapy and intracavitary after-loading brachytherapy is the main therapeutic method. Development of three dimensional treatment planning system is the foundation and key in the research fields of intracavitary brachytherapy. The preliminary research on design and verification of HDR ¹⁹²Ir after-loading brachytherapy simulation system (ABSS) has been implemented in our research according to the real conditions of two dimensional brachytherapy planning systems in China.First of all, the main advances in the research of HDR ¹⁹²Ir intracavitary after-loading brachytherapy have been reviewed, including the following aspects: 1. current trend and status in quo of HDR ¹⁹²Ir intracavitary brachytherapy, 2. development of HDR ¹⁹²Ir source and change of the measuring methods about the basic dose parameters of source, like the constant of dose rate (A), radial dose function (g(r)) and the anisotropy function(F(r, θ)), 3. improvement of HDR ¹⁹²Ir brachytherapy accuracy because of the application of 3D-TPS based on CT, MRI and PET images, and methods of measuring the 3D dose distributions and dose in vivo, 4. measures for improving the dose distributions of target and normal tissues, which includes the application of IMRT.Most of the after-loading brachytherapy systems used in the radiotherapy centers in China are HDR ¹⁹²Ir systems, almost all of the TPS of which are two dimensional systems based on the conventional X-ray films, which have no 3D dose calculation...