Duan Xiaoyu, Huang Hailiang, Zhao Wei
Stony Brook Medicine, Department of Radiology, Stony Brook, New York, United States.
J Med Imaging (Bellingham). 2025 Jan;12(Suppl 1):S13002. doi: 10.1117/1.JMI.12.S1.S13002. Epub 2024 Jul 24.
Accurate detection of microcalcifications ( ) is crucial for the early detection of breast cancer. Some clinical studies have indicated that digital breast tomosynthesis (DBT) systems with a wide angular range have inferior detectability compared with those with a narrow angular range. This study aims to (1) provide guidance for optimizing wide-angle (WA) DBT for improving detectability and (2) prioritize key optimization factors.
An DBT pipeline was constructed to evaluate detectability of a WA DBT system under various imaging conditions: focal spot motion (FSM), angular dose distribution (ADS), detector pixel pitch, and detector electronic noise (EN). Images were simulated using a digital anthropomorphic breast phantom inserted with clusters. Evaluation metrics included the signal-to-noise ratio (SNR) of the filtered channel observer and the area under the receiver operator curve (AUC) of multiple-reader multiple-case analysis.
Results showed that FSM degraded sharpness and decreased the SNR and AUC by 5.2% and 1.8%, respectively. Non-uniform ADS increased the SNR by 62.8% and the AUC by 10.2% for filtered backprojection reconstruction with a typical clinical filter setting. When EN decreased from 2000 to 200 electrons, the SNR and AUC increased by 21.6% and 5.0%, respectively. Decreasing the detector pixel pitch from 85 to improved the SNR and AUC by 55.6% and 7.5%, respectively. The combined improvement of a pixel pitch and EN200 was 89.2% in the SNR and 12.8% in the AUC.
Based on the magnitude of impact, the priority for enhancing detectability in WA DBT is as follows: (1) utilizing detectors with a small pixel pitch and low EN level, (2) allocating a higher dose to central projections, and (3) reducing FSM. The results from this study can potentially provide guidance for DBT system optimization in the future.
准确检测微钙化对于乳腺癌的早期发现至关重要。一些临床研究表明，与窄角范围的数字乳腺断层合成（DBT）系统相比，宽角范围的DBT系统的微钙化检测能力较差。本研究旨在（1）为优化广角（WA）DBT以提高微钙化检测能力提供指导，以及（2）确定关键优化因素的优先级。
构建了一个WA DBT流程，以评估WA DBT系统在各种成像条件下的微钙化检测能力：焦点运动（FSM）、角剂量分布（ADS）、探测器像素间距和探测器电子噪声（EN）。使用插入微钙化簇的数字拟人乳腺模型模拟图像。评估指标包括滤波通道观察者的信噪比（SNR）和多读者多病例分析的接收者操作特征曲线下面积（AUC）。
结果表明，FSM降低了微钙化的清晰度，使SNR和AUC分别降低了5.2%和1.8%。对于采用典型临床滤波设置的滤波反投影重建，不均匀的ADS使SNR提高了62.8%，AUC提高了10.2%。当EN从2000电子降低到200电子时，SNR和AUC分别提高了21.6%和5.0%。将探测器像素间距从85减小到[未给出具体数值]，分别使SNR和AUC提高了55.6%和7.5%。像素间距和EN200的联合改善使SNR提高了89.2%，AUC提高了12.8%。
基于影响程度，在WA DBT中提高微钙化检测能力的优先级如下：（1）使用具有小像素间距和低EN水平的探测器，（2）向中央投影分配更高剂量，以及（3）减少FSM。本研究结果可能为未来DBT系统的优化提供指导。
