Choi Sang Lim, Park Sung Bin, Yang Seungwook, Lee Eun Sun, Park Hyun Jeong, Lee Jong Beum, Choi Byung Ihn
Department of Radiology, Chung-Ang University Hospital, Chung-Ang University College of Medicine, Seoul, Korea.
Samsung Electronics, Suwon, Korea.
Curr Med Imaging. 2021;17(11):1356-1362. doi: 10.2174/1573405617666210218094812.
Kidney, Ureter, and Bladder radiography (KUB) has frequently been used in suspected urolithiasis, but its performance is known to be lower than that of Computed Tomography (CT). This study aimed to investigate the diagnostic performance of digitally KUB in the detection of ureteral stones.
Thirty patients who underwent digital KUB and CT were included in this retrospective study. The original digital KUB underwent post-processing that involved noise estimation, reduction, and whitening in improving the visibility of ureteral stones. Thus, 60 digital original or post-processed KUB images were obtained and ordered randomly for blinded review. After a period, a second review was performed after unblinding stone laterality. The detection rates were evaluated at both initial and second reviews, using CT as a reference standard. The objective (size) and subjective (visibility) parameters of ureteral stones were analyzed. Fisher's exact test was used to compare the detection sensitivity between the original and post-processed KUB data set. Visibility analysis was assessed with a paired t-test. The correlation of stone size between CT and digital KUB data sets was assessed with the Pearson's correlation test.
The detection rate was higher for most reviewers once stone laterality was provided and was non-significantly better for the post-processed KUB images (p > 0.05). There was no significant difference in stone size among CT and digital KUB data sets. In all reviews, visibility grade was higher in the post-processed KUB images, irrespective of whether stone laterality was provided.
Digital post-processing of KUB yielded higher visibility of ureteral stones and could improve stone detection, especially when stone laterality was available. Thus, digitally post-processed KUB can be an excellent modality for detecting ureteral stones and measuring their exact size.
肾脏、输尿管和膀胱X线摄影（KUB）常用于疑似尿路结石的检查，但已知其诊断效能低于计算机断层扫描（CT）。本研究旨在探讨数字化KUB在输尿管结石检测中的诊断效能。
本回顾性研究纳入了30例行数字化KUB和CT检查的患者。对原始数字化KUB图像进行后处理，包括噪声估计、降噪和图像美白，以提高输尿管结石的可视性。由此获得60幅数字化原始或后处理KUB图像，并随机排序进行盲法阅片。一段时间后，在知晓结石位置后进行第二次阅片。以CT作为参考标准，评估初次和第二次阅片时的检测率。分析输尿管结石的客观（大小）和主观（可视性）参数。采用Fisher精确检验比较原始和后处理KUB数据集之间的检测敏感性。采用配对t检验评估可视性分析结果。采用Pearson相关检验评估CT和数字化KUB数据集之间结石大小的相关性。
一旦提供结石位置，大多数阅片者的检测率更高，后处理KUB图像的检测率虽有提高但差异无统计学意义（p>0.05）。CT和数字化KUB数据集之间的结石大小无显著差异。在所有阅片中，无论是否提供结石位置，后处理KUB图像的可视性等级均更高。
KUB的数字化后处理提高了输尿管结石的可视性，可改善结石检测，尤其是在知晓结石位置时。因此，数字化后处理的KUB可成为检测输尿管结石并测量其确切大小的优良检查方法。
