Epidemiological and imaging features that can affect the detection of ureterolithiasis on ultrasound

Abstract Objective: To identify, in patients with clinical suspicion of ureterolithiasis, epidemiological and imaging features that affect calculus detection on ultrasound, as well as to compare ultrasound with multidetector computed tomography (MDCT). Materials and Methods: We searched our database for patients who underwent ultrasound, followed by MDCT (if the ultrasound was negative), for suspected ureterolithiasis in an emergency setting. Patients were divided into three groups: positive ultrasound (US+); negative ultrasound/positive MDCT (US−/MDCT+); and negative ultrasound/negative MDCT (US−/MDCT−). We evaluated age, gender, ureterolithiasis laterality, location of the calculus within the ureter, body mass index, calculus diameter, and calculus attenuation on MDCT. Results: Of a total of 292 cases of suspected ureterolithiasis, 155 (53.1%) were in the US+ group, 46 (15.7%) were in the US−/MDCT+ group, and 91 (31.2%) were in the US−/MDCT− group. There were no significant differences among the groups in terms of age, gender, ureterolithiasis laterality, and mean MDCT attenuation values. Distal ureterolithiasis was most common in the US+ group, and calculi at other ureteral locations were more common in the US−/MDCT+ group. The mean body mass index was significantly higher in the US−/MDCT+ group than in the US+ group, and the mean calculus diameter was significantly greater in the US+ group than in the US−/MDCT+ group. Conclusion: A high body mass index, large calculus diameter, and calculus location in the distal third of the ureter are the major factors favoring ureterolithiasis detection on ultrasound.

摘要 研究目的：针对临床疑似输尿管结石症（ureterolithiasis）的患者，明确影响超声检出结石的流行病学与影像学特征，并对比超声与多排螺旋计算机断层扫描（multidetector computed tomography, MDCT）的诊断效能。
材料与方法：我们检索本机构数据库，纳入急诊情境下疑似输尿管结石症，且先后接受超声检查，若超声结果为阴性则进一步行MDCT检查的患者。将患者分为三组：超声阳性组（US+）、超声阴性/MDCT阳性组（US−/MDCT+）以及超声阴性/MDCT阴性组（US−/MDCT−）。我们评估了患者的年龄、性别、输尿管结石侧别、结石在输尿管内的位置、体重指数、结石直径以及MDCT影像下的结石衰减值。
结果：共计纳入292例疑似输尿管结石症患者，其中US+组155例（占比53.1%），US−/MDCT+组46例（占比15.7%），US−/MDCT−组91例（占比31.2%）。三组患者在年龄、性别、结石侧别以及MDCT下结石平均衰减值方面均无统计学差异。US+组以输尿管远端结石最为多见，而输尿管其他部位的结石在US−/MDCT+组中占比更高。US−/MDCT+组的平均体重指数显著高于US+组，US+组的平均结石直径显著大于US−/MDCT+组。
结论：高体重指数、较大的结石直径以及结石位于输尿管远端三分之一段，是提升超声检出输尿管结石症效能的主要影响因素。