IJMPCERO  Vol.6 No.2 , May 2017
TrueBeam Low Dose Rate Investigation for Pulsed Reduced Dose Rate IMRT
Abstract: The capability of the TrueBeam treatment system to deliver step and shoot IMRT plans at low dose rates was evaluated. Beam characteristics during low dose rates (5 to 100 MU/min) were evaluated for consistency using a planar ion chamber array. MU constancy, linearity, and beam profile symmetry were all found to be equivalent within 0.5%. The response of the Scandi Dos Delta 4 system was also evaluated at low dose rates of using static open beams compared to ion chamber measurements, and step and shoot IMRT plans comparing 5 - 20 MU/min and 100 MU/min dose rates, with a maximum observed absolute dose difference of 0.8% and equivalence margin of 0.2%. The Gamma Index and measurement reproducibility were also found to be equivalent.
Cite this paper: Geurts, M. (2017) TrueBeam Low Dose Rate Investigation for Pulsed Reduced Dose Rate IMRT. International Journal of Medical Physics, Clinical Engineering and Radiation Oncology, 6, 139-149. doi: 10.4236/ijmpcero.2017.62013.

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