System of coordinates used in this study to express the position of the 192Ir brachytherapy source relative to the mPSD. The center of scintillator (Scint.) #1 was defined as z = 0, r = 0.
Experimental setup and positioning template system (embedded). Catheters were connected to transfer tubes, which were connected to the afterloader. The PSD was connected to the spectrometry setup outside the treatment room (Ref. 29 ).
For (a) r = 1 cm, (b) r = 2 cm, (c) r = 3 cm, and (d) r = 5 cm: (Top) Dose measured by each scintillating element (Scint.) together with the calculated expected dose. (Bottom) Accuracy of the measurement. Scint.1 is at z = 0 cm, scint. 2 at z = 2.53 cm, and scint. 3 at z = 4.99 cm.
Effect of the weighted approach combining measurements from each scintillating element (Scint.) on dose measurement accuracy at r = 3 cm.
Effect of various dose thresholds on the averaged accuracy measurement for scintillating element #3.
Relative uncertainty of the measurements from scintillating element #2 as a function of integration time and radial source-to-mPSD distance.
Effects of the measurement, position, and total uncertainties on precision for all three scintillating elements: (a) Scint. 1, (b) Scint. 2, (c) Scint. 3 at r = 1 cm.
Maps of the offset between the expected and calculated positions of the 192Ir source as a function of the position of each of the scintillators (Scint.) and of the weighted approach. Scintillator 1 is at z = 0 cm, scintillator 2 at z = 2.53 cm, and scintillator 3 at z = 4.99 cm.
The variables of dose determination and how uncertainties were calculated.
Averaged accuracy and standard deviation (sd) for dose measurement by each scintillating element (Scint.) of the mPSD and with the weighted combination for different radial distances r.
Proportion of the measured positions above or below a certain position offset threshold for the each scintillating element (Scint.) and for the weighted approach.
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