Management Outcomes of Shock Wave Lithotripsy in Ureteral Stones: Evaluation of Radiological and Patient-Related...

The aim of this study was to determine the possible predictive value of certain radiological and stone-related factors on the stone free (SF) rates following shock wave lithotripsy (SWL) in patients with upper ureteral calculi on a stone location-based manner.

The success rates of SWL applications in a total of 190 patients (146 males, 44 females M/F: 3.32) presenting with ureteral stones were evaluated in detail. The impact of certain radiological and patient-related factors on the success rates particularly with an emphasis on the stone location was evaluated. Variables analyzed were the diameter of ureteric portion proximal to the stone, grade of hydronephrosis, stone size, stone density, and ureteral wall thickness at the impacted stone site. Success rates in terms of final SF status were evaluated after 4 weeks with non-contrast computer tomography (NCCT) examination.

All patients had a single ureteral stone. A total of 141 stones were located in the upper ureter and the remaining 49 stones were located in the middle ureter. While the mean age of the cases was 41.59 ± 11.66 years (range 17-72 years), mean stone size was 8.47 mm (4.1-23.7 mm). Following SWL, while a total of 108 (76.6%) patients with upper ureteric stones were completely SF at 4-week follow-up visit; this value was 25 (51.0%) in cases with middle ureteral stones. Although the diameter of the stone was in the same range with no meaningful difference, stone length and stone density were significantly higher in upper ureteral stones (p: 0.002 and p: 0.007, respectively). Proximal ureteral stones were found to be disintegrated in a more successful manner with higher SF rates compared to ureteral stones located in the mid portion of the ureter (p: 0.001).

Prediction of the final outcome of SWL in patients with upper ureteral stones is a challenging issue and our data did clearly indicate a meaningful relationship between UWT and the success rates of SWL particularly in cases requiring additional procedures. Of all the evaluated stone and related factors, only UWT was found to be higher in proximal ureteral calculi at the stone site which could help us to predict the likelihood of stone disintegration in these parts of the involved ureter.