Study On Medical Image Preprocessing And Visualiztion Application Technology In IMRT Invrse Planning System

The purpose of radiotherapy is to kill the tumor cells and protect the surrounding normaltissue and organ at risk. The intensity modulated radiation therapy (IMRT) is the primarydirection of radiation therapy.The treatment plan is needed before implementing the radiotherapy. A completethree-dimensional radiotherapy plan system need to describe the relationship between diseasearea, normal tissue and organ at risk in the human body accurately, and the dose distribution bydifferent dose calculation method need to be visualized, which could help plan maker evaluatedifferent treatment plans.This work is supported by National Natural Science Foundation of China (60872112)–"The study of multi-objective optimization algorithm and objective function in IMRT inverseplanning", and the Natural Science Foundation of Zhejiang Province (Z207588)–"Research onthe key problems on the inverse planning in the intensity Modulated Radiation Therapy". Themain work of the thesis is:1. A hybrid filter algorithm is proposed and implemented to CT image. This algorithm hasbetter capability on noise suppression and detail data preservation. It provides clearer image toplan maker.2. After analyze of several classical regions filling algorithms, a method using interactivedelineation tool to save the coordinate information of interested area is realized based on VTK,Bezier curve algorithm, and the improved Watershed algorithm. With this method, theinformation in the delineated area is accurately extracted.3. Based on the exploration of the principle and features about two different kindvisualization methods, the three-dimensional dose distribution visualization is implemented inIMRT inverse planning system by VTK .