使用人体乳房模型的获得性乳腺 X 线摄影图像的模型观察者研究。

A model observer study using acquired mammographic images of an anthropomorphic breast phantom.

机构信息

Dutch Expert Centre for Screening (LRCB), Radboud University Medical Center, Wijchenseweg 101, 6538 SW, Nijmegen, The Netherlands.

Department of Radiology and Nuclear Medicine, Radboud University Medical Center, PO Box 9101, 6500 HB, Nijmegen, The Netherlands.

出版信息

Med Phys. 2018 Feb;45(2):655-665. doi: 10.1002/mp.12703. Epub 2017 Dec 21.

DOI:10.1002/mp.12703

PMID:29193129

Abstract

PURPOSE

To study the feasibility of a task-based framework composed of an anthropomorphic breast phantom and mathematical model observers (MOs) for the evaluation of system-processed mammographic images.

METHODS

A prototype anthropomorphic breast phantom with inserted gold discs of 0.1 mm and 0.25 mm diameter was imaged with two digital mammography systems (system A and B) at four different dose levels. From the acquired processed and unprocessed images, signal-present and signal-absent regions of interest (ROIs) were extracted. The ROIs were evaluated by a non-pre-whitening MO with eye filter (NPWE) and by three human observers in a two-alternative forced-choice experiment. We compared the human and the MO performance on a simple detection task of the calcification-like discs in ROIs with and without postprocessing. Proportion of correct responses of the human (PC ) and NPWE (PC ) experiments was calculated and the correlation between the two was analyzed using a mixed-effect regression model. Correlation results including the goodness of fit (r ) of PC and PC for all different parameters investigated were evaluated to determine whether NPWE MO can be used to predict human observer performance.

RESULTS

PC and PC increased with dose for all conditions investigated (signal size, processing status, and different system). In case of the 0.1 mm discs, for system A, r between PC with PC was 0.81. For system B, r was 0.93. In case of the 0.25 mm discs, r in system A was 0.79 and for system B, r was 0.82. For the combined parameters investigated, and after excluding the 0.1 mm discs on system A because the results were influenced by aliasing, the overall r was 0.81. Image processing did not affect the detectability of calcification-like signals. No significant difference (P > 0.05) was found between the predicted PC by the MO and the PC for all different conditions.

CONCLUSIONS

The framework seems promising to be used in objective image quality assessment. It was found to be relatively robust for the range of parameters investigated. However, further optimization of the anthropomorphic breast phantom and investigation of other MOs for a broader range of image quality assessment tasks is needed.

摘要

目的

研究基于拟人乳房体模和数学模型观察者（MO）的任务型框架用于评估系统处理的乳腺图像的可行性。

方法

使用两个数字乳腺摄影系统（系统 A 和 B）对具有插入 0.1 毫米和 0.25 毫米直径金盘的原型拟人乳房体模进行成像，在四个不同的剂量水平下进行。从获取的处理和未处理图像中，提取了存在和不存在信号的感兴趣区域（ROI）。通过非预白化 MO 和眼睛滤波器（NPWE）以及两名人类观察者在二选一强制选择实验中对 ROI 进行了评估。我们比较了在有和没有后处理的 ROI 中进行钙化样盘状检测任务时人类和 MO 的性能。计算了人类（PC）和 NPWE（PC）实验的正确反应比例，并使用混合效应回归模型分析了两者之间的相关性。评估了所有不同参数调查的 PC 和 PC 之间的相关性结果，包括拟合度（r），以确定 NPWE MO 是否可以用于预测人类观察者的性能。

结果

对于所有研究的条件（信号大小、处理状态和不同的系统），PC 和 PC 都随剂量的增加而增加。对于 0.1 毫米的盘状物，在系统 A 中，PC 与 PC 之间的 r 值为 0.81。在系统 B 中，r 值为 0.93。对于 0.25 毫米的盘状物，在系统 A 中的 r 值为 0.79，在系统 B 中的 r 值为 0.82。对于调查的综合参数，并且由于系统 A 上的 0.1 毫米盘状物的结果受到混叠的影响而排除在外后，整体 r 值为 0.81。图像处理不会影响钙化样信号的可检测性。对于所有不同的条件，MO 预测的 PC 和 PC 之间没有显著差异（P>0.05）。