Computer Assisted Determination of the Tumor Area and Location on Radiation Therapy Treatment System using Computed Tomography Images

• Main Authors: Huan Chen, 陳煥
• Other Authors: Hui Peng
• Format: Others
• Language: en_US
• Published: 1995
• Online Access: http://ndltd.ncl.edu.tw/handle/72994141298557320355

碩士 === 國立清華大學 === 電機工程研究所 === 83 === In radiotheraphy, decreasing the total treatment dosage will reduce the side effect on a patient. On the contrary, decreasing the total treatment dosage lowers the tumor control probability of the patients. Accurate tumor localization for radiotherapy treatment appears to be very important because it allows to increase the dosage on the tumor and reduce simultaneously the dosage on the normal tissues. We develop computer techniques to determine the relative positions of the patient under radiotherapy treatment and under computed tomography scan and to find the tumor location and area on simulation film from the computed tomography(CT). The simulation film is an X-ray film of the simulator for determining radiation area before real treatment on the linear accelerator. This approach uses a quantized rank circular minimum mean square error(QRCMMSE) operator to find the optimal matching center between CT projection image and simulation film. The location and area of tumor are consequently determined by projecting the CT slices with the tumor contours, marked by the oncologist previously, onto a transparency to be overlaid with the simulation film. This computer techniques can also revise the rotation error if existing. Experimental results show that the algorithm are quite accurate in performing the desired task. This technique could be need to give more effective, less harmful and more efficient radiation therapy treatment.