Wigati Kristina T, Marshall Nicholas W, Lemmens Kim, Binst Joke, Jacobs Annelies, Cockmartin Lesley, Zhang Guozhi, Vancoillie Liesbeth, Petrov Dimitar, Vandenbroucke Dirk A N, Soejoko Djarwani S, Bosmans Hilde
KU Leuven, Department of Imaging and Pathology, Leuven, Belgium.
Universitas Indonesia, Department of Physics, Depok, Indonesia.
J Med Imaging (Bellingham). 2021 Mar;8(2):023505. doi: 10.1117/1.JMI.8.2.023505. Epub 2021 Apr 27.
The relevance of presampling modulation transfer function (MTF) measurements in digital mammography (DM) quality control (QC) is examined. Two studies are presented: a case study on the impact of a reduction in MTF on the technical image quality score and analysis of the robustness of routine QC MTF measurements. In the first study, two needle computed radiography (CR) plates with identical sensitivities were used with differences in the 50% point of the MTF ( ) larger than the limiting value in the European guidelines ( change between successive measurements). Technical image quality was assessed via threshold gold thickness of the CDMAM phantom and threshold microcalcification diameter of the L1 structured phantom. For the second study, presampling MTF results from 595 half-yearly QC tests of 55 DM systems (16 types, six manufacturers) were analyzed for changes from the baseline value and changes in between successive tests. A reduction of 20% in of the two CR plates was observed. There was a tendency to a lower score for task-based metrics, but none were significant. Averaging over 55 systems, the absolute relative change in between consecutive tests (with 95% confidence interval) was 3% (2.5% to 3.4%). Analysis of the maximum relative change from baseline revealed changes of up to for one a-Se based system and for a group of CsI-based systems. A limit of 10% is a relevant action level for investigation. If exceeded, then the impact on performance has to be verified with extra metrics.
研究了预采样调制传递函数（MTF）测量在数字乳腺摄影（DM）质量控制（QC）中的相关性。介绍了两项研究：一项关于MTF降低对技术图像质量评分影响的案例研究，以及对常规QC MTF测量稳健性的分析。在第一项研究中，使用了两张灵敏度相同的针状计算机X线摄影（CR）板，其MTF的50%点差异大于欧洲指南中的限值（连续测量之间的变化）。通过CDMAM体模的阈值金厚度和L1结构化体模的阈值微钙化直径评估技术图像质量。对于第二项研究，分析了55个DM系统（16种类型，6个制造商）的595次半年期QC测试的预采样MTF结果，以确定与基线值的变化以及连续测试之间的变化。观察到两张CR板的MTF降低了20%。基于任务的指标有得分降低的趋势，但均无显著性。对55个系统进行平均，连续测试之间MTF的绝对相对变化（95%置信区间）为3%（2.5%至3.4%）。对与基线相比的最大相对变化分析表明，一个基于非晶硅的系统变化高达，一组基于碘化铯的系统变化高达。10%的限值是进行调查的相关行动水平。如果超过该限值，则必须用额外的指标验证对性能的影响。
