2. Title: Percutaneous Nephrolithotomy versus Extracorporeal Shockwaves Lithotripsy for Treatment of a 20-30 mm Single Renal Pelvis Stone Authors: Mohammed Hassan, Ahmed R. EL-Nahas, Khaled Z. Sheir, Nasr A. El-Tabey, Ahmed M. El-Assmy and Ahmed A. Shokeir Affiliation: Urology Department, Urology and Nephrology Center, Mansoura University, Mansoura, Egypt

3. Aim of the study  To compare the efficacy, safety and cost of extracorporeal shockwaves lithotripsy (SWL) and percutaneous nephrolithotomy (PNL) in treatment of a 20-30 mm single renal pelvis stone.

4. Patients and Methods  Retrospective Study  Between January 2006 and December 2012  Exclusion criteria: – –Patients aged <18 years, – –Branched stone – –Advanced hydronephrosis, – –Solitary kidney, anatomical renal abnormality – –Received treatment for this stone within the past 6 months.

5.  In PNL group: –Prone position –Fluoroscopic guided renal puncture –Dilatation with Alken’s metal dilator to 30 F –Disintegrated: ultrasonic or pneumatic –A 22 F nephrostomy tube was placed and left for 24-48 hours Patients and Methods

6.  In SWL group: –Electromagnetic Dornier lithotripter S (Dornier MedTech GmbH, Germering, Germany) was used. –Shockwaves were delivered at a rate of 80 shocks/minutes till a maximum of 3000 shocks per session. Patients and Methods

7. Evaluation  The stone free status was evaluated 3 months after PNL or last SWL session by NCCT.  Success included patients who became stone free or had insignificant residual (4 mm or less). Comparison: The 2 groups were compared for:  Re-treatment rate, secondary procedures  The costs of primary and secondary procedures Patients and Methods

8. Results

9. SWL 167 Patients PNL 170 Patients P Patients characters Age (years) Mean ± SD47.7 ± 11.750.9 ± 12.40.018 BMI Mean ± SD31.6 ± 4.631.9 ± 7.40.589 Stone character Side 0.449 Right Left 77 (46%) 90 (54%) 84 (49.4%) 86 (50.6%) Largest diameter (mm)23.5 ± 2.725.1 ± 3< 0.001 Stone surface area (mm 2 )295 ± 100383 ± 136< 0.001 SSD (cm, mean ± SD)9.9 ± 1.910.6 ± 2.50.011 Attenuation value (HU)826 ± 353740 ± 3590.122

10. SWL 167 Patients PNL 170 Patients P Efficacy N. (%) N. (%) Success 115 (75%)162 (95.3%) < 0.001 Re-treatment 126 (75.4%)9 (5.3%) < 0.001 Secondary procedure 42 (25%)8 (4.7%) < 0.001 Results

11. SWL 167 Patients PNL 170 Patients P Safety N. (%) N. (%) Complications (Clavien Class.) overall G I G II G IIIa 11 (6.6) 0 (0) 4 (2.4) 7 (4.2) 22 (12.9) 7 (4.1) 6 (3.5) 9 (5.3) 0.050 Total Cost ($US) < 0.001 Median (Range) 490 (350-1820) 1120 (1118-1750) Results

12. Conclusions  For treatment of a single renal pelvis stone of 20-30 mm: –PNL was more effective than SWL. –SWL had lesser complications and lower cost.