Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, Kyoto, 606-8507, Japan.
Preemptive Medicine and Lifestyle-Related Disease Research Center, Kyoto University Hospital, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, Kyoto, 606-8507, Japan.
Eur Radiol. 2019 Dec;29(12):6439-6442. doi: 10.1007/s00330-019-06314-5. Epub 2019 Jul 4.
Temporal subtraction of CT (TS) images improves detection of newly developed bone metastases (BM). We sought to determine whether TS improves detection of BM by radiology residents as well.
We performed an observer study using a previously reported dataset, consisting of 60 oncology patients, each with previous and current CT images. TS images were calculated using in-house software. Four residents independently interpreted twice the 60 sets of CT images, without and with TS. They identified BM by marking suspicious lesions likely to be BM. Lesion-based sensitivity and number of false positives per patient were calculated. Figure-of-merit (FOM) was calculated. Detectability of BM, with and without TS, was compared between radiology residents and board-certified radiologists, as published previously.
FOM of residents significantly improved by implementing TS (p value < 0.0001). Lesion-based sensitivity, false positives per patients, and FOM were 40.8%, 0.121, and 0.657, respectively, without TS, and 58.1%, 0.0958, and 0.796, respectively, with TS. These findings were comparable with the previously published values for board-certified radiologists without TS (58.0%, 0.19, and 0.758, respectively).
The detectability of BM by residents improved markedly by implementing TS and reached that of board-certified radiologists without TS.
• Detectability of bone metastases on CT by residents improved significantly when using temporal subtraction of CT (TS). • Detections by residents with TS and board-certified radiologists without TS were comparable. • TS is useful for residents as it is for board-certified radiologists.
CT（TS）图像的时间减影可提高对新发生骨转移（BM）的检测。我们旨在确定放射科住院医师是否也能通过 TS 提高 BM 的检测能力。
我们进行了一项观察者研究，使用了先前报道的数据集，该数据集由 60 名肿瘤患者组成，每个患者均有先前和当前的 CT 图像。使用内部软件计算 TS 图像。四位住院医师分别独立地对 60 组 CT 图像进行两次解读，一次是不带 TS，一次是带 TS。他们通过标记可疑的 BM 病变来识别 BM。计算基于病变的敏感性和每位患者的假阳性数量。计算了功效系数（FOM）。先前发表的研究已经比较了带和不带 TS 时放射科住院医师和认证放射科医师对 BM 的检测能力。
实施 TS 后，住院医师的 FOM 显著提高（p 值<0.0001）。不带 TS 时，基于病变的敏感性、每位患者的假阳性和 FOM 分别为 40.8%、0.121 和 0.657，而带 TS 时，分别为 58.1%、0.0958 和 0.796。这些发现与先前发表的不带 TS 的认证放射科医师的值相当（58.0%、0.19 和 0.758）。
实施 TS 后，住院医师对 BM 的检测能力显著提高，达到了不带 TS 的认证放射科医师的水平。
• 对 CT 上骨转移的检测能力，通过使用 CT 时间减影（TS），住院医师的检测能力显著提高。• 带 TS 的住院医师和不带 TS 的认证放射科医师的检测结果相当。• TS 对住院医师和认证放射科医师都有用。
