Aim: 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 Material and methods: 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 were 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 was evaluated after 4 weeks with non-contrast computer tomography (NCCT) examination. Results: All patients had a single ureteral stone. A total of 141 stones were located in the upper ureter and 49 in the middle ureter. The mean age was 41.59±11.66 years (range 17–72), and the mean stone size was 8.47 mm (4.1–23.7 mm). After SWL, 108 patients (76.6%) with upper ureteral stones were SF at the 4-week follow-up, whereas this rate was 25 (51.0%) in patients with middle ureteral stones. Although stone diameter was similar between groups, stone length and density were significantly higher in upper ureteral stones (p=0.002 and p=0.007, respectively). Proximal ureteral stones showed higher disintegration and SF rates than mid-ureteral stones (p=0.001). Conclusions: 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.
Güzel et al. (Thu,) studied this question.