Istanbulluoglu MO et al, 2010: Shock wave lithotripsy for distal ureteric stones: supin or prone
Istanbulluoglu MO, Hoscan MB, Tekin MI, Cicek T, Ozturk B, Ozkardes H
Department of Urology, Konya Education Hospital, Baskent University School of Medicine, 42060, Konya, Turkey
Shock wave lithotripsy (SWL) has become the preferred first-line approach to most patients with symptomatic urolithiasis. The purpose of this study is to assess the ideal patient position during SWL for the treatment of distal ureter stones. A total of 342 patients included in this retrospective study. 148 (108 men, 40 women) patients were included in the first group and were treated in supine position. The remaining 194 (143 men, 51 women) patients were included to second group and were treated in prone position. This study designed retrospectively. The procedure was accepted as a success if the patient was stone free or had only clinically insignificant fragments (≤3 mm) for 3 months or more after the last SWL session. Before SWL, the mean is one area in the first group was 61.32 mm2 while the mean stone area in the second group was 59.04 mm2 (p = 0.208). Mean energy, Mean energy maximum and mean number of applied shock waves of the first group was 4.65, 3.19 and 3,960, respectively. The same parameters in second group were 4.26, 3.03 and 2,953, respectively. These results show that there are statistically significant differences between two groups with respect to mean energy, mean energy maximum and mean number of applied shock waves (p = 0.003, p = 0.010, p = 0.000, respectively). Success rate was 85.1% in group 1 and 72.7% in group 2 (p = 0.006). Our results suggest that supine position is effective and better than prone position for SWL in patients with distal ureteric stones.
Urol Res. 2011 Jun;39(3):177-80. doi: 10.1007/s00240-010-0322-1. Epub 2010 Oct 21
PMID: 20963407 [PubMed - in process]
A randomization was carried out of 342 patients with distal ureteral stones. 148 were treated in supine position and 194 in prone position. Significantly better results were recorded for patients in the supine position.
Several considerations are indeed necessary for choosing the best treatment position, such as the interference of the shock wave path with the skeleton and with intestinal gas. Therefore, it is difficult to give general recommendations on the best treatment position and an individualized approach is probably the best strategy, although I personally also prefer administration of shock waves from the back when treating patients with distal ureteral stones.
One advantage of this study is that the authors have expressed to stone size in terms of surface area.