Clinical quality assurance of intensity modulated radiation therapy
- VernacularTitle:逆向计划调强适形放射治疗的质量保证
- Author:
Gaofeng LI
;
Miaosheng ZHU
;
Qinhong WU
;
Hong GAO
;
Jingxue HE
;
Xia XIU
- Publication Type:Journal Article
- Keywords:
Intensity modulated radiation therapy;
Inverse planning;
Fluence map;
Anthropomorphic phantom
- From:
Chinese Journal of Radiation Oncology
1993;0(03):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To evaluate the clinical feasibility of quality assurance of intensity modulated radiation therapy(IMRT) through a series of clinical case studies. Methods Helios inverse planning system was used to provide optimized IMRT treatment plans for brain tumor, nasopharyngeal carcinoma, pancreatic cancer, spinal metastatic tumor and prostatic cancer. To verify the conformation between the fluence map of each beam predicted by the planning system and that actually delivered, a piece of film under a homogeneous polystyrene phantom was irradiated vertically with each of the beams to record the deposited dose. This measured fluence map was compared with that predicted by the planning. The dose distribution was recorded by irradiating the film in an anthropomorphic phantom using patients' treatment plan, then compared with that predicted by the planning. An ionization chamber in a water phantom was used to measure the central point dose and another eccentric point dose. Results The fluence map measured by the film was well consistent with that predicted by the planning. The error between the measured dose and predicted dose in the central point was less than 3%, whereas the error of the dose in another eccentric point varied greatly. The isodose distribution (on axial plane) measured by the film was consisent with the predicted one. Conclusions The procedures for quality assurance of IMRT are feasible in our experience.
