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STUK-A196 TAPIOVAARA Markku. STUK-A196. Objective Measurement of Image Quality in Fluoroscopic X-ray Equipment: FluoroQuality. Helsinki 2003, 50 pp. + apps. 13 pp. Keywords medical imaging, x-ray imaging, fluoroscopy, image quality, statistical decision theory, ideal observer, quasi-ideal observer, detectability, signal-to-noise ratio, SNR, accumulation rate of the signal-to-noise ratio squared, SNR2rate, Wiener spectrum, spatio-temporal noise power spectrum, NPS, temporal lag, optimisation, quality control, measurement method, computer program Abstract The report describes FluoroQuality, a computer program that is developed in STUK and used for measuring the image quality in medical fluoroscopic equipment. The method is based on the statistical decision theory (SDT) and the main measurement result is given in terms of the accumulation rate of the signal-to-noise ratio squared (SNR2rate). In addition to this quantity several other quantities are measured. These quantities include the SNR of single image frames, the spatio-temporal noise power spectrum and the temporal lag. The measurement method can be used, for example, for specifying the image quality in fluoroscopic images, for optimising the image quality and dose rate in fluoroscopy and for quality control of fluoroscopic equipment. The theory behind the measurement method is reviewed and the measurement of the various quantities is explained. An example of using the method for optimising a specified fluoroscopic procedure is given. The User’s Manual of the program is included as an appendix. The program is available free of charge for research work and program evaluation purposes by contacting the author. 3