Chakraborty D P, Eckert M P
Department of Radiology, Hospital of the University of Pennsylvania, Philadelphia 19104, USA.
Med Phys. 1995 Feb;22(2):133-43. doi: 10.1118/1.597463.
The precision of quantitative and subjective evaluations of phantom image quality has been studied. Twenty-seven images of the American College of Radiology (ACR) mammography accreditation phantom were acquired under different x-ray techniques and digitized. Several quantitative image quality measures were obtained from each image by analyzing microcalcification and nodule target objects in the phantom. All images were also scored subjectively by 8 observers, each of whom provided a count of the number of objects seen in each target class (fibrils, microcalcifications, and nodules). An analysis was performed to predict the subjective measurements from the quantitative measurements and to estimate their variabilities. It was found that the subjective measures could be well predicted by the quantitative measures and that the variance of the quantitative measures was significantly smaller than that of the subjective measure, by almost a factor of 10. The implication for the ACR accreditation program for mammography is that a substantial improvement is possible in the image quality evaluation process by performing computerized analysis of the phantom images in addition to subjective analysis.
对乳腺摄影体模图像质量的定量和主观评估精度进行了研究。在不同的X射线技术下采集了27张美国放射学会（ACR）乳腺摄影认证体模的图像并进行数字化处理。通过分析体模中的微钙化和结节目标物体，从每张图像中获得了几种定量图像质量指标。所有图像还由8名观察者进行主观评分，每位观察者对每个目标类别（纤维、微钙化和结节）中看到的物体数量进行计数。进行了一项分析，以从定量测量中预测主观测量结果并估计其变异性。结果发现，主观测量结果可以通过定量测量很好地预测，并且定量测量的方差明显小于主观测量的方差，几乎相差10倍。对于ACR乳腺摄影认证计划而言，这意味着除了主观分析之外，通过对体模图像进行计算机化分析，图像质量评估过程有可能得到实质性改善。
