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Quality Control of Medical Imaging Displays
Published in Paolo Russo, Handbook of X-ray Imaging, 2017
Alisa Walz-Flannigan, Heather Weber
The following suggestions for luminance and grayscale calibration are written to be consistent with the ACR-AAPM-SIIM Technical Standard (ACR-AAPM-SIIM 2017). For displays for diagnostic use, the minimum luminance (Lmin) should be at least 4-times the ambient luminance (Lamb) and L′min = Lmin + Lamb and should be at least 1.0 cd/m2. For displays not used for diagnosis (where consistent presentation is not required), a Lmin of 0.8 cd/m2 is ok.The maximum luminance should be set so that the Luminance Ratio, LR = (Lmax + Lamb)/(Lmin + Lamb) should be at least 350 for diagnostic displays. For other monitors, a LR of at least 250 is sufficient. The Lmax of diagnostic monitors used for interpretation should be at least 350 cd/m2 and, for mammography, this should be at least 420 cd/m2. Brighter monitors should be calibrated to keep the same target LR. For displays to be consistent in presentation with diagnostic displays, they should have the same LR and Lmax. Lmax values from displays attached to the same workstation do not vary by more than 10%.Luminance values between Lmax and Lmin should conform to the values set by the DICOM GSDF. Contrast response conformance with the GSDF, as defined in the AAPM TG 18 Task Group Report, should be within 10% for primary diagnostic displays over all DDL. For other monitors, the contrast response should be within 20%.Color differences should not be visible between displays. A recommended white point for standardization corresponds to the CIE daylight standard D65 white point.Mammography displays may have other specific calibration targets and tolerances required of them by the mammography equipment QC manual, followed as specified by the ACR (American College of Radiology) and MQSA (Mammography Quality Standards Act).
Singular secular Kuznets-like period realized amid industrial transformation in US FDA medical devices: a perspective on growth from 1976 to 2020
Published in Expert Review of Medical Devices, 2022
Beginning in 1976 to present, the PMN/PMA regulatory construct has taken 40 years to evolve; maturing over a backdrop of significant economic events [8,15,16], substantive policy changes [6,7,9,17,18], as well as major alterations in the tapestry of innovation levers (e.g. increases in governmental R&D expenditure [19], the volume of intellectual property [20,21], and other sciento-economic metrics [22]). Economic recessions (1973–1975, 1980, and 1981–1982, and 2007) and shocks (notably, the 1987 Black Monday, the 2001 Dot-Com Crash, and the 2020 COVID-19 pandemic) have not been uncommon during this period [15,16], and MD policy changes rapidly promulgated [9,17]: The 1976 amendments to the Federal Food, Drug, and Cosmetic (FD&C) Act, the 1990 Safe Medical Devices Act (SMDA), the 1992 Mammography Quality Standards Act (MQSA), 1997 FDA Modernization Act (FDAMA), the 2002 Medical Device User Fee and Modernization Act (MDUFMA) and its Reauthorization in 2007, 2012, and 2017, the 2016 21st Century Cures Act, the 2012 FDA Safety and Innovation Act (FDASIA), and a slew of responses to the COVID-19 crisis [18].