多层螺旋CT在尿路结石诊断中的价值

Evaluation of the ureteral stone with multi-slice CT

目的研究泌尿系结石中各种CT表现,分析直接征象及间接征象在诊断尿路结石中的价值。方法182例患者因临床疑为泌尿系结石而行螺旋CT检查,其中128例确诊为结石,25例被确认为结石排石后病例。另外29例确诊为非结石病例。CT平扫后行增强扫描,分别获得皮质期,实质期及分泌期图像。分析CT表现,并记录尿路结石的直接及间接征象。结果对于8种CT表现,两个观察者之间Kappa值分别为0.96、0.94、0.93、0.96、0.89、0.91、0.93和0.84,均显示有极高的判断一致性。在结石的诊断中,直接征象具有最高的诊断准确性(85.2%)和敏感性(83.7%)。但间接征象组织环征的特异性高于直接征象为96.6%。当用直接征象结合二个以上的间接征象为诊断结石的标准时,可以得到96.2%的准确性,99.3%敏感性。结论在泌尿系结石的诊断中,结石的直接征象结合两个及两个以上的间接征象可明显提高结石的诊断的敏感性及准确性,并能诊断结石排出后的病例。

Objective To assess the usefulness of combined direct and indirect CT signs on multi-slice spiral CT for the diagnosis of ureteral stones. Methods One hundred and eighty-two patients who were suspected having ureteral stones were recruited in this prospective study. Among them, 128 patients were finally diagnosed as having ureteral stones, 25 patients having passed urinary stones, and 29 patients having diseases of non-ureteral stones. CT examinations were performed with MSCT, and CT plain, arterial-phase, nephrographlc-phases, and excretory-phase images were obtained. The direct and indirect CT signs of ureteral stones were reviewed and analyzed. Results The Kappa values of inter-observer agreement for direct and 7 indirect signs were0.96, 0.94, 0.93, 0.96, 0.89, 0.91, 0.93 and 0.84, respectively. The direct sign had the highest accuracy （85.2%） and sensitivity （83.7%） for the diagnosis ureteral stones among the all signs, however, an indirect sign, tissue-ring sign, had the highest specificity （96.6%）. When combined the direct sign and two or more indirect signs to diagnose the ureteral stones, the accuracy and sensitivity will be 96. 2% and 99. 3%, respectively. Conclusion Combined the direct and indirect sign of ureteral stones can greatly improve the diagnostic accuracy and sensitivity for ureteral stones, and indirect signs will be helpful in diagnosis of passed urinary stone.