Stone Treatment Index: A Mathematical Summary of the Procedure for Removal of Stones from the Urinary Tract

Arguments for choosing extracorporeal shockwave lithotripsy for removal of urinary tract stones

At a time when there is an almost unlimited enthusiasm and preference among urologists for endoscopic stone removal, we have found it essential to meet some of the frequently presented arguments on why extracorporeal shockwave lithotripsy (SWL) should not be used. We have based our considerations in this brief article on our 30-35 years' experience with the non-invasive or least invasive technique that SWL represents. Stone disintegration, requirement of repeated treatment sessions, the concern of residual fragments, complications and economic aspects are some points that are discussed.

Comparison of outcomes after percutaneous nephrolithotomy of staghorn calculi in those with single and multiple accesses

PURPOSE

To analyze the early outcome after single tract vs multiple tracts percutaneous nephrolithotomy (PCNL) in the management of staghorn calculi.

PATIENTS AND METHODS

The records of 413 patients with staghorn calculi (223 [54%] had complete and 190 [46%] had partial) who underwent PCNL were reviewed retrospectively. A total of 244 (59%) patients were managed by single access (group 1); meanwhile, multiple accesses were necessary in 169 (41%) patients (group 2). Both groups were compared in terms of perioperative findings and postoperative outcomes. Patients and stone-related factors affecting the number of accesses performed were analyzed.

RESULTS

The mean number of percutaneous accesses was 2.42 +/- 0.74 (range 2-6) in group 2. Mean durations of fluoroscopy screening time and operative time were significantly longer in group 2 (P = 0.002, P < 0.0001, respectively). Supracostal access was necessary in 30.7% in group 2 and in 6.9% in group 1 (P = 0.001). Success was achieved in 70.1% in group 1 and in 81.1% for group 2 after one session of PCNL (P = 0.012). The most common complication was bleeding for both groups, and it was higher in group 2 (P < 0.0001). The mean preoperative and postoperative creatinine concentrations were 1.03 mg/dL and 1.08 mg/dL in group 1, and 0.9 mg/dL and 1.03 mg/dL in group 2, respectively. The mean changes in creatinine values were not statistically significant between the groups (P = 0.16).

CONCLUSIONS

The impact of PCNL using either single or multiple access tracts on renal function is similar and of a temporary nature. PCNL with multiple accesses is a highly successful alternative with considerable complication rates in the management of staghorn calculi.

How efficient is extracorporeal shockwave lithotripsy with modern lithotripters for removal of ureteral stones?

PURPOSE

To analyze results of extracorporeal shockwave lithotripsy (SWL) for treatment of ureteral stones with two modern lithotripters.

PATIENTS AND METHODS

A consecutive series of 598 patients with ureteral stones was treated with the Modulith SLX Classic and Modulith SLX-F2 lithotripters. The mean (SD) age of the patients was 54 (17) years, and the mean (SD) stone surface area was 42 (34) mm2. Results were available for 580 patients.

RESULTS

Stone-free ureters were recorded in 563 (97.1%) patients. Stone-free rates were 96.1%, 97.8%, and 97.9%, for the proximal, middle, and distal ureter, respectively. The average number of SWL sessions needed was 1.31. For the proximal, middle, and distal ureter, one SWL session was sufficient in 73.1%, 66.7%, and 83.2% of patients, respectively. Assisting auxiliary procedures were used in 102 patients (18%). The total mean (SD) treatment time was 48 (26) minutes and the mean (SD) number of shockwaves was 3266 (2258). SWL for stones located in the proximal, middle, and distal ureter was carried out in the prone position in 38%, 88%, and 9%, respectively. For 90 patients primarily treated with a large focus, the re-treatment rate was the same as for patients treated with a standard focus. A stone treatment index used to assess the efforts, results, and complications was similar for the two lithotripters and for all stone locations. Thus both lithotripters had similar efficacy.

CONCLUSION

With consistent use of SWL, a stone-free rate of more than 97% can be attained, with a reasonable re-treatment rate and only modest use of assisting auxiliary procedures.