Examples of fractional measured ionization collection errors due to system leakage current for a 200 cGy IMRT dose distribution measurement for a variety of ionization chamber volumes and system leakage currents. (a) Measurement error for a volume ionization chamber. (b) Measurement error for a volume ionization chamber. (c) Measurement error for a volume ionization chamber.
Example of a matrix detector.
Superimposed dose distributions intended to compare IMRT dose distributions. In this case, the solid and dashed lines are the calculated and measured distributions, respectively. When the superimposed isodoses overlap, the reviewer can readily see that they agree. However, when the doses differ, such as in the high-dose region in this example, a quantitative evaluation is difficult. Reference is from Childress et al. (Ref. 162).
Example of dose distribution evaluation and display tools. Examples are from Childress and Rosen (Ref. 162).
Numerically defined dose distributions provided to illustrate dose distribution comparison tools. Examples are from Low and Dempsey (Ref. 163).
Example of the use of the and angle tools is from Stock et al. (Ref. 164).
Comparison between and as defined by Bakai et al. (Ref. 175).
A partial list of commercially available small-volume ion chambers. For standard Imaging/Exradin chambers, the chamber materials are designated as model A—Shonka C552, model M—pure magnesium, and T—Shonka A150.
Summary of a few commercially available solid state detectors.
Summary of some commercially available electrometers.
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