论文信息 - [Accuracy of dynamic multileaf position and influence of beam profile according to change in dose monitor unit in QA plan of intensity modulated radiotherapy].

[Accuracy of dynamic multileaf position and influence of beam profile according to change in dose monitor unit in QA plan of intensity modulated radiotherapy].

The number of dose monitor units in IMRT QA plans differs form the actual conditions of IMRT in dosimetry for verification of dynamic multileaf-IMRT (DMLC-IMRT). We measured the accuracy of the position of the dynamic multileaf collimator and the dose profile for various numbers of dose monitor units, and verified the accuracy of dosimetry in an IMRT QA plan. The accuracy of the position of the dynamic multileaf collimator was measured by using the software of the external irradiation device, and the dose profile was measured by using the semiconductor profiler. Deviation in the position of the dynamic multileaf collimator increased as the number of dose monitor units decreased. When deviation in the position of the dynamic multileaf collimator was large and the gap width of the multileaf collimator was narrow, the change in dose profile was large. Therefore, verification of IMRT QA plans requires a phantom and measurement device close to the actual conditions of IMRT.

[1] D. Axen,et al. Verification of dynamic intensity-modulated beam deliveries in canine subjects. , 2001, Medical physics.

[2] B. Heijmen,et al. Testing of the stability of intensity modulated beams generated with dynamic multileaf collimation, applied to the MM50 racetrack microtron. , 2000, Medical physics.

[3] S Mutic,et al. Characterization of a commercial multileaf collimator used for intensity modulated radiation therapy. , 2001, Medical physics.

[4] T LoSasso,et al. Comprehensive quality assurance for the delivery of intensity modulated radiotherapy with a multileaf collimator used in the dynamic mode. , 2001, Medical physics.

[5] C. Ling,et al. Physical and dosimetric aspects of a multileaf collimation system used in the dynamic mode for implementing intensity modulated radiotherapy. , 1998, Medical physics.