CT-related parameters and Framingham score as predictors of spontaneous passage of ureteral stones ≤ 10 mm: results from a prospective, observational, multicenter study

To investigate the reliability of newly defined CT-related parameters and cardiovascular risk factors in groups adjusted for stone size and location to predict spontaneous stone passage (SP) of uncomplicated ureteral stones ≤ 10 mm. The data of 280 adult patients with solitary unilateral ureteral stones ≤ 10 mm in diameter in non-contrast computed tomography were prospectively recorded. All patients undergoing a four-week observation protocol with medical expulsive therapy using tamsulosin were divided into two groups according to SP or no SP. Demographic, clinical and radiological findings of these groups were recorded. Spontaneous stone passage was observed in 176 (62.9%) of the patients, whereas the SP rate was 57.6% for 118 upper ureteral stones and 66.7% for 162 lower ureteral stones. The SP rate was 13.3 times greater with ureteral wall thickness < 1.88 mm, 4.4 times greater with a ratio of ureter to stone diameter of < 1.24, 3.4 times greater with Framingham score of < 11.5%, 2 times greater with neutrophil lymphocyte ratio < 1.96, 1.9 times greater with ureteral diameter < 6.33 mm and 1.5 times greater with stone volume < 38.54 mm3. Lower levels of ureteral wall thickness, ratio of ureter to stone diameter, Framingham score, neutrophil lymphocyte ratio, ureteral diameter, stone volume and absence of hydronephrosis were found to be more successful predictors. We consider that the success rate can be increased by selection of the proper option (observation or active treatment) according to these predictors.