Can ureteric stone impaction be predicted preoperatively using noninvasive parameters? A prospective study

Abstract

Objective To determine the potential predictive value of different non-contrast computed tomography (NCCT) parameters and acute phase markers (ESR and CRP) for identifying impacted ureteric stones preoperatively.Methods We included 70 patients with ureteric stones who underwent ureteroscope (URS) in this study. The NCCT parameters and acute phase reactants were measured and compared in the impacted and non-impacted stone groups using univariate and multivariate analysis.Results Out of the 70 patients, 35 had impacted ureteric stones. Using univariate analysis, we found that stone volume, stone location, hydronephrosis grade, and ureteral wall thickness (UWT) were the variables affecting the impaction, while by multivariate analysis, no significant association was detected between impaction and stone volume (p = 0.42). No association was found between the acute phase reactants and prediction of stone impaction Based on the receiver operating characteristic (ROC) curve analysis, UWT cutoff of 1.9 mm is an excellent predictor of impaction with 72.2% sensitivity, 94.1% specificity, and an overall accuracy level of 82.9%.Conclusion Stone location, hydronephrosis grade and UWT were the best predictors for ureteric stone impaction preoperatively.