Kim Seung Ja, Moon Woo Kyung, Cho Nariya, Cha Joo Hee, Kim Sun Mi, Im Jung-Gi
Department of Radiology, Konkuk University Hospital, Seoul, Korea.
Korean J Radiol. 2007 May-Jun;8(3):198-205. doi: 10.3348/kjr.2007.8.3.198.
To evaluate the performance and reproducibility of a computeraided detection (CAD) system in mediolateral oblique (MLO) digital mammograms taken serially, without release of breast compression.
A CAD system was applied preoperatively to the fullfield digital mammograms of two MLO views taken without release of breast compression in 82 patients (age range: 33-83 years; mean age: 49 years) with previously diagnosed breast cancers. The total number of visible lesion components in 82 patients was 101: 66 masses and 35 microcalcifications. We analyzed the sensitivity and reproducibility of the CAD marks.
The sensitivity of the CAD system for first MLO views was 71% (47/66) for masses and 80% (28/35) for microcalcifications. The sensitivity of the CAD system for second MLO views was 68% (45/66) for masses and 17% (6/35) for microcalcifications. In 84 ipsilateral serial MLO image sets (two patients had bilateral cancers), identical images, regardless of the existence of CAD marks, were obtained for 35% (29/84) and identical images with CAD marks were obtained for 29% (23/78). Identical images, regardless of the existence of CAD marks, for contralateral MLO images were 65% (52/80) and identical images with CAD marks were obtained for 28% (11/39). The reproducibility of CAD marks for the true positive masses in serial MLO views was 84% (42/50) and that for the true positive microcalcifications was 0% (0/34).
The CAD system in digital mammograms showed a high sensitivity for detecting masses and microcalcifications. However, reproducibility of microcalcification marks was very low in MLO views taken serially without release of breast compression. Minute positional change and patient movement can alter the images and result in a significant effect on the algorithm utilized by the CAD for detecting microcalcifications.
评估计算机辅助检测（CAD）系统在不松开乳房压迫的情况下对连续拍摄的内外斜位（MLO）数字乳腺钼靶片的性能及可重复性。
对82例（年龄范围：33 - 83岁；平均年龄：49岁）先前诊断为乳腺癌的患者，在不松开乳房压迫的情况下，将CAD系统术前应用于两个MLO位的全场数字乳腺钼靶片。82例患者中可见病变成分总数为101个：66个肿块和35个微钙化。我们分析了CAD标记的敏感性和可重复性。
CAD系统对首次MLO位片检测肿块的敏感性为71%（47/66），检测微钙化的敏感性为80%（28/35）。CAD系统对第二次MLO位片检测肿块的敏感性为68%（45/66），检测微钙化的敏感性为17%（6/35）。在84组同侧连续MLO图像集（2例患者为双侧癌）中，无论有无CAD标记，35%（29/84）获得了相同图像，29%（23/78）获得了带有CAD标记的相同图像。对侧MLO图像中，无论有无CAD标记，65%（52/80）获得了相同图像，28%（11/39）获得了带有CAD标记的相同图像。连续MLO位片中真阳性肿块的CAD标记可重复性为84%（42/50），真阳性微钙化的CAD标记可重复性为0%（0/34）。
数字乳腺钼靶片中的CAD系统在检测肿块和微钙化方面显示出高敏感性。然而，在不松开乳房压迫的情况下连续拍摄的MLO位片中，微钙化标记的可重复性非常低。微小的位置变化和患者移动会改变图像，并对CAD用于检测微钙化的算法产生显著影响。
