Assessing the usefulness of the quasi-ideal observer for quality control in fluoroscopy

The aim of this work was to evaluate the reliability of the square of the signal-to-noise ratio rate, SNRrate2, as a precise measurement for quality control test in a digital fluoroscopy system. The quasi-ideal model observer was used to measure SNRrate2. The dose rate, pulse rate and field of view were varied, and their effect on dose efficiency, defined as SNRrate2/PKA,rate, was evaluated (where PKA,rate is the air kerma-area product rate). Measurements were repeated to assess reproducibility. The relative standard deviation in SNRrate2/PKA,rate over seven consecutive measurements was 5 %. No significant variation in SNRrate2/PKA,rate was observed across different pulse rates (10–30 pulses s–1). The low-dose-rate setting had a superior dose efficiency compared with the medium- and high-dose-rate settings. A smaller field of view resulted in higher dose efficiency.
The results show that SNRrate2/PKA,rate measurements offer the high precision required in quality control constancy tests.

Source: Radiation Protection Dosimetry - June 6, 2016 Category: Radiology Authors: Tesselaar, E., Sandborg, M. Tags: Paper Source Type: research