Research Of Radiotherapy Set-up Error Analysis And Improvement Method For Carcinoma Of The Cervix

Cervical cancer is one of the most common malignancies in the female compatriotsin China, the incidence rate of the first in the female genital malignancies, mortality aftergastric cancer is the second largest in all malignancies, patients30-60years old femaleSee. Cervical cancer treatment options are surgery and radiation treatment, andcomprehensive treatment also has a lot of advantages. Radiation therapy as the primarymeans of treatment, surgery can not match these advantages. But in the process ofradiation therapy, due to mechanical deviation immobilization device for patients fixederrors, improper posture patient setup process and other factors, give radiation therapyprecision resulting in varying degrees of impact, thus affecting the radiation treatmentplanning precise implementation, reduce the rate of tumor control in patients. Set-uperrors, improved patient immobilization device study analysis of patients with cervicalcancer radiation therapy is an important guarantee of the efficacy of radiation therapy, isthe key to improve tumor control rate.In this thesis, by actual clinical measurements of different immobilization deviceset-up error, combined with treatment planning system beam parameters to be measuredusing the same method of vacuum bag and body heat plastic film two immobilizationdevice, found that patients with the vacuum bag immobilization deviate from theradiation treatment planning system default center to the end of radiotherapy, the actualtreatment center7.02mm, and the immobilization of patients with body heat plastic film,its center offset value of5.25mm, and in each observation period, the body heat plasticfilm body immobilization in patients than in a vacuum bag fixed position error is smaller.The body heat plastic film more suitable for use in patients with orthostatic fixed. Findout the vacuum bag and body thermoplastic film aspects of patient positioning themfixed positioning error causes of error from the fixed principles of radiation therapy equipment, immobilization device, the radiation therapy treatment technicians humanoperation discussed.Body heat plastic film immobilization device a improvement, the body heat plasticfilm is improved, to the end of the treatment of patients, the actual treatment center offsetradiation treatment planning system default center for3.64mm, compared withimprovements before with smaller set-up error, offset volume of patients up and downdirection toward the top of the offset positioning staples play better results. The bodyheat plastic film was better for patient body fixture.