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Nelms, B.E., Chan, M.F., Jarry, G., Lemire, M., Lowden, J., Hampton, C. and Feygelman, V. (2013) Evaluating IMRT and VMAT Dose Accuracy: Practical Examples of Failure to Detect Systematic Errors When Applying a Commonly Used Metric and Action Levels. Medical Physics, 40, Article ID: 111722.
http://dx.doi.org/10.1118/1.4826166

has been cited by the following article:

• TITLE: Gamma-Index Passing Rates in Baseline Plans Measured with a Detector Array

  AUTHORS: Stanislaw Szpala, Kirpal Kohli

  KEYWORDS: Gamma Index, Detector Array, ArcCHECK, Delivery Error

  JOURNAL NAME: International Journal of Medical Physics, Clinical Engineering and Radiation Oncology, Vol.4 No.4, November 11, 2015

  ABSTRACT: Purpose: This study provides a simple protocol for validation of the gamma passing rates and to identify the optimum values of % dose and mm criteria for dose distributions measured with a detector array. Methods: We chose ArcCHECK detector array to illustrate the concepts. We used plans with uniform or quasi-uniform dose distributions along the detector array for testing in the presence of dose errors. For testing sensitivity to spatial shift we employed a plan with approximately constant dose gradient along the axis of the instrument. Results: We identified a representative set of parameters which describe performance of a detector array. We determined the minimum gamma-index acceptance criteria allowing the passing rates to reach 100% in the absence of errors, and identified the minimum fully detectable errors for such criteria. For our baseline plans delivered to ArcCHECK, 100% passing rates were obtained for 1.5% dose criterion together with ±3% minimum error detectable at 100% rate, and for 1.5 mm criterion together with the minimum fully detectable error of ±3 mm. We inspected the impact of selected program options on the passing rates. Conclusions: The protocol we developed provides a simple method of commissioning-style analysis of a detector array without a need for analysis of a large number of clinical plans.