The dose verification of external electrically-driven multi-leaf collimator in the treatment plan of IMRT / 中国医学装备

ABSTRACT

Objective:To verify the dose of static and dynamic intensity modulated radiotherapy (IMRT) through 2-dimension ionization chamber matrix after external electrically-driven multi-leaf collimator (MLC) was installed in KB1800 medical linear accelerator. Methods: 40 patients who need receive IMRT were divided into static IMRT group (20cases) and dynamic IMRT group (20cases) as the random number table. The ionization chamber was applied to implement scale dose, and solid water and 2-D ionization chamber matrix was applied to verify dose. Besides, the feasibility of static and dynamic IMRT were compared and researched.Results: The verification results of plane dosage of static IMRT plan and dynamic IMRT plan showed that the passing rates both of them were above 90.0%, and the verification of intensity modulated dosimetry of medical electric linear accelerator KB1800 with external electric MLC was consistent with standard.Conclusion:After the external electrically-driven MLC is installed on the accelerator, the dosage of IMRT can achieve the verification standard, and it can be applied to clinical treatment and can satisfy the requirement of clinical radiotherapy.