Abstract：Objective To study the using of cerrobase as the compensation material in the intensity-modulated radiation therapy (IMRT) implementation and impact factors. Methods With therapy planning system (TPS) exported the radiation field intensity file (Dicom RT), through measuring the attenuation coefficient of cerrobase, to calculate the processing depth of AUTIMO 3D CNC corresponding for Dicom RT files at each pixel, then using the processed foam casting of Cerrobase, produced the required IMRT compensator. Through the MATRIXX testing the IMRT compensator in clinical implementation. At the same time we compared the MU of using multi-leaf collimator (MLC) and Cerrobase IMRT compensator for 10 patients. Results With cerrobase compensation IMRT can get similar dose or dose distribution to dose produced by TPS for point or plane dose, error is within 5%.To comparison with MLC, using cerrobase compensator has fewer treatment times ((4.44±0.39) min∶(5.71±0.57) min (t=10.82,P=0.000)) and fewer MU (462.5±65.8) MU∶(524.5±99.6) MU (t=3.14,P=0.012)). Conclusions Comparison with MLC IMRT, the cerrobase compensation technique has an important application value with its unique advantages. This research provides an implemented method of IMRT radiotherapy for the primary hospital.
LI Jie,QI Guo-hai,LI Jian et al. Clinical applied study for cerrobase compensator intensity-modulated radiotherapy technique[J]. Chinese Journal of Radiation Oncology, 2012, 21(3): 278-280.
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2012, Vol. 21 
