Comparability of three output prediction models for a compact passively double‐scattered proton therapy system

@article{Ferguson2017ComparabilityOT,
  title={Comparability of three output prediction models for a compact passively double‐scattered proton therapy system},
  author={Sven Ferguson and Yong Chen and Clara Ferreira and Mohammad Rafiqul Islam and Vance P. Keeling and Andy Lau and Salahuddin Ahmad and Hosang Jin},
  journal={Journal of Applied Clinical Medical Physics},
  year={2017},
  volume={18},
  pages={108 - 117}
}
&NA; The purpose of this study was to investigate comparability of three output prediction models for a compact double‐scattered proton therapy system. Two published output prediction models are commissioned for our Mevion S250 proton therapy system. Model A is a correction‐based model (Sahoo et al., Med Phys, 2008;35(11):5088–5097) and model B is an analytical model which employs a function of r = (R’‐M’)/M’ (Kooy et al., Phys Med Biol, 2005;50:5487–5456) where R’ is defined as depth of distal… 

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References

SHOWING 1-10 OF 13 REFERENCES
Implementation of output prediction models for a passively double-scattered proton therapy system.
TLDR
The first existing model has proven to be a successful predictor of output for the authors' compact double-scattering proton therapy system and either model with r3 thus can serve well as an output prediction calculator.
Implementation of an improved dose‐per‐MU model for double‐scattered proton beams to address interbeamline modulation width variability
TLDR
A parameterized linear‐quadratic transformation is introduced to convert the nominal modulation width to the measured modulation width for each beam option or suboption on a per‐beamline basis to extend the MGH output model to more general clinic situations.
The prediction of output factors for spread-out proton Bragg peak fields in clinical practice.
TLDR
This work describes the calibration and protocol for SOBP fields, the effects of apertures and range-compensators and the use of output factors in the treatment planning process, and describes the implementation of this framework in clinical practice.
A procedure for calculation of monitor units for passively scattered proton radiotherapy beams.
TLDR
The authors conclude that an intuitive formula similar to the one used for monitor unit calculation of therapeutic photon beams can be used to compute the monitor units of passively scattered proton therapy beams.
Commissioning and initial experience with the first clinical gantry‐mounted proton therapy system
TLDR
Clinically, the Mevion S250 proton therapy system operates well and has provided an excellent platform for the treatment of diseases with protons.
Evaluation of monitor unit calculation based on measurement and calculation with a simplified Monte Carlo method for passive beam delivery system in proton beam therapy
TLDR
A DMU calculation method combining measurement data and calculation with a simplified Monte Carlo method for the double scattering system in proton beam therapy at the National Cancer Center Hospital East in Japan will be able to substitute the conventional DMU measurement for the majority of clinical cases with a reasonable calculation time required for clinical use.
Uncertainty in dose per monitor unit estimates for passively scattered proton therapy: The role of compensator and patient scatter in prostate cases
TLDR
The water-to-patient absorbed dose conversion factor, F CSPS, is estimated, which accounts for differences in scatter (from the range compensator and internal patient anatomy) between patient treatments and their corresponding calibration irradiation in a homogeneous water-box-phantom, suggesting that uncertainty in FCSPS for proton treatments of prostate cancer is clinically acceptable.
Scatter factors in proton therapy with a broad beam.
TLDR
An estimator using a dose calculation based on the pencil beam algorithm is developed and implemented in a treatment planning system (TPS) for clinical use and observed 2-3% differences between the measurements and the estimations.
Monitor unit calculations for range-modulated spread-out Bragg peak fields.
TLDR
A theoretical derivation of the ratio of SOBP plateau dose to the dose measured in the ionization reference chamber is used to establish the relationship between the output factor and the distal range and modulation width of the S OBP.
A pencil beam algorithm for proton dose calculations.
TLDR
A pencil beam algorithm for proton dose calculations which takes accurate account of the effects of materials upstream of the patient and of the air gap between them and the patient is developed.
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