***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: PURPOSE We determined the preferred treatment of staghorn calculi . MATERIAL S AND METHODS Between January 1992 and December 1994 we performed a prospect i ve , r and omized , single center study involving 50 kidneys with complete staghorn calculi : 27 renal units were treated with extracorporeal shock wave lithotripsy ( ESWL ) monotherapy ( group 1 ) and 23 were treated with combined ( initial ) percutaneous nephrostolithotomy with ESWL ( group 2 ) . The 2 treatment groups were compared regarding stone size , grade of collecting system dilatation and urine culture at presentation . The number of treatment sessions , narcotic doses , renal colic episodes , septic complications , unplanned ancillary procedures , length of hospitalization , total treatment duration and stone-free rate at 6 months were recorded and compared . RESULTS At the conclusion of therapy the stone-free rate was significantly greater in group 2 than in group 1 ( 74 versus 22 % , respectively , p = 0.0005 ) . The complication rate was significantly greater in group 1 , with 15 septic complications ( fever greater than 38.5C for longer than 3 days ) in 10 patients compared to only 2 episodes in group 2 ( p = 0.007 ) . The unplanned ancillary procedure rate was significantly greater in group 1 ( 8 procedures in 7 patients versus 1 procedure in group 2 , p = 0.03 ) . The overall treatment length was significantly shorter in group 2 ( 1 versus 6 months , p = 0.0006 ) . There was no significant difference in the number of procedures performed with anesthesia or in the number of hospitalization days between the 2 treatment groups . CONCLUSIONS Combined percutaneous nephrostolithotomy and ESWL should be recommended as the first line treatment choice for most patients with staghorn stones PURPOSE We compared the efficacy of shock wave lithotripsy and ureteroscopy for treatment of distal ureteral calculi . MATERIAL S AND METHODS A total of 64 patients with solitary , radiopaque distal ureteral calculi 15 mm . or less in largest diameter were r and omized to treatment with shock wave lithotripsy ( 32 )  using an HM3 lithotriptor ( Dornier MedTech , Kennesaw , Georgia ) or ureteroscopy ( 32 ) . Patient and stone characteristics , treatment parameters , clinical outcomes , patient satisfaction and cost were assessed for each group . RESULTS The 2 groups were comparable in regard to patient age , sex , body mass index , stone size , degree of hydronephrosis and time to treatment . Procedural and operating room times were statistically significantly shorter for the shock wave lithotripsy compared to the ureteroscopy group ( 34 and 72 versus 65 and 97 minutes , respectively ) . In addition , 94 % of patients who underwent shock wave lithotripsy versus 75 % who underwent ureteroscopy were discharged home the day of procedure . At a mean followup of 21 and 24 days for shock wave lithotripsy and ureteroscopy , respectively , 91 % of patients in each group had undergone imaging with a plain abdominal radiograph , and all studies showed resolution of the target stone . Minor complications occurred in 9 % and 25 % of the shock wave lithotripsy and ureteroscopy groups , respectively ( p value was not significant ) . No ureteral perforation or stricture occurred in the ureteroscopy group . Postoperative flank pain and dysuria were more severe in the ureteroscopy than shock wave lithotripsy group , although the differences were not statistically significant . Patient satisfaction was high , including 94 % for shock wave lithotripsy and 87 % for ureteroscopy ( p value not significant ) . Cost favored ureteroscopy by $ 1,255 if outpatient treatment for both modalities was assumed . CONCLUSIONS Ureteroscopy and shock wave lithotripsy were associated with high success and low complication rates . However , shock wave lithotripsy required significantly less operating time , was more often performed on an outpatient basis , and showed a trend towards less flank pain and dysuria , fewer complications and quicker convalescence . Patient satisfaction was uniformly high in both groups . Although ureteroscopy and shock wave lithotripsy are highly effective for treatment of distal ureteral stones , we believe that HM3 shock wave lithotripsy , albeit slightly more costly , is preferable to manipulation with ureteroscopy since it is equally efficacious , more efficient and less morbid BACKGROUND To establish the best treatment modality in our hospitals for patients with proximal-ureteral calculi 5 to 10 mm , we compared the treatment outcome in those who underwent  primary ureteroscopy ( URS )  with that in patients who underwent primary in-situ SWL . The primary endpoints were stone-free rates at 3 weeks and 3 months and the subjective patient experience . PATIENTS AND METHODS The study was a prospect i ve patient-preference trial . From September 2002 to May 2005 , 80 patients were included , of whom 71 could be evaluated . Thirty-three patients were treated with SWL and 38 with semirigid or flexible URS .  Stone status was evaluated with excretory urography or noncontrast helical CT . The bother score of urinary-tract symptoms was recorded on a visual analog scale . RESULTS The stone-free rate at 3 weeks was 58 % and 78 % ( P = 0.061 ) and at 3 months 88 % and 89 % ( P = 1 ) for SWL and URS , respectively . The percentage of patients in need of analgesics was 30 % and 49 % ( P = 0.118 ) at 3 weeks and 9 % and 21 % ( P = 0.181 ) at 3 months for the SWL and the URS group , respectively . The bother score regarding dysuria , hematuria , and flank pain were statistically significant in favor of SWL . CONCLUSION Ureteroscopy tends to make patients stone free faster , but SWL is preferred by most patients because there is less discomfort after treatment OBJECTIVES To conduct a prospect i ve and r and omized trial to compare the efficiency quotient and cost-effectiveness index of shock wave lithotripsy ( SWL ) and ureteroscopic lithotripsy ( URSL ) for the treatment of large upper third ureteral stones . METHODS A total of 35 male patients and 7 female patients with a solitary , radiopaque upper ureteral stone , 15 mm or more in diameter , who underwent SWL or URSL were enrolled in this study . The mean patient age was 53.1 + /- 14.5 years . The endpoint of the study was for the patient to be stone free or to have insignificant residual stone ( 3 mm or less ) within the kidney . RESULTS The mean stone length + /- SD was 17.9 + /- 3.9 cm in the SWL group and 18.5 + /- 2.9 cm in the URSL group ( P > 0.05 ) . The efficiency quotient for SWL and URSL was 0.61 and 0.63 , respectively . The cost-effectiveness index , treatment time , pain score , and hospital stay were greater in the URSL group . However , the degree of hydronephrosis significantly influenced the success rate of SWL . All patients with severe hydronephrosis in the SWL group needed auxiliary surgical procedures to become stone free . CONCLUSIONS The efficiency quotients of SWL and URSL were comparable in the treatment of large upper third ureteral stones . However , SWL should not be recommended as the first-line treatment option for the management of upper third ureteral stones larger than 1.5 cm with severe hydronephrosis . Underst and ing the cost-effectiveness , success rate , pain score , and patient satisfaction score for the two different approaches constitutes the indispensable requisites for choosing the optimal first-line therapeutic strategy PURPOSE We determined the natural course and compared the deleterious effects in kidneys of shock wave lithotripsy , percutaneous nephrolithotomy and observation for asymptomatic lower caliceal stones . MATERIAL S AND METHODS Between April 2007 and August 2008 patients with asymptomatic lower caliceal calculi were enrolled in the study . To assess stone status noncontrast abdominal helical computerized tomography was done 3 and 12 months after intervention . All patients were evaluated by dimercapto-succinic acid renal scintigraphy 6 weeks and 12 months after intervention . RESULTS A total of 94 patients were prospect ively r and omized to percutaneous nephrolithotomy  ( 31 ) , shock wave lithotripsy  ( 31 ) and  observation  ( 32 ) . Mean + /- SD followup was 19.3 + /- 5 months ( range 12 to 29 ) . In the percutaneous nephrolithotomy group all patients were stone-free at month 12 . Scintigraphy revealed a scar in 1 patient ( 3.2 % ) on month 3 followup imaging . In the shock wave lithotripsy group the stone-free rate was 54.8 % . Scintigraphy revealed scarring in 5 patients ( 16.1 % ) . In the observation group 7 patients ( 18.7 % ) required intervention during followup . Median time to intervention was 22.5 + /- 3.7 months ( range 18 to 26 ) . One patient ( 3.1 % ) had spontaneous stone passage . Scintigraphy did not reveal scarring in any patient . CONCLUSIONS Stone related events were noted in more than 20 % of patients with asymptomatic lower caliceal stones observed expectantly . To manage lower caliceal stones percutaneous nephrolithotomy has a significantly higher stone-free rate with less renal scarring than shock wave lithotripsy . Thus , patients with asymptomatic lower caliceal stones must be informed in detail about all management options , especially focusing on percutaneous nephrolithotomy with its outst and ing outcome PURPOSE The efficacy of shock wave lithotripsy and percutaneous stone removal for the treatment of symptomatic lower pole renal calculi was determined . MATERIAL S AND METHODS A prospect i ve r and omized , multicenter clinical trial was performed comparing shock wave lithotripsy and percutaneous stone removal for symptomatic lower pole only renal calculi 30 mm . or less . RESULTS Of 128 patients enrolled in the study 60 with a mean stone size of 14.43 mm . were r and omized to percutaneous stone removal ( 58 treated , 2 awaiting treatment ) and 68 with a mean stone size of 14.03 mm . were r and omized to shock wave lithotripsy ( 64 treated , 4 awaiting treatment ) . Followup at 3 months was available for 88 % of treated patients . The 3-month postoperative stone-free rates overall were 95 % for percutaneous removal versus 37 % lithotripsy ( p < 0.001 ) . Shock wave lithotripsy results varied inversely with stone burden while percutaneous stone-free rates were independent of stone burden . Stone clearance from the lower pole following shock wave lithotripsy was particularly problematic for calculi greater than 10 mm . in diameter with only 7 of 33 ( 21 % ) patients becoming stone-free . Re-treatment was necessary in 10 ( 16 % ) lithotripsy and 5 ( 9 % ) percutaneous cases . There were 9 treatment failures in the lithotripsy group and none in the percutaneous group . Ancillary treatment was necessary in 13 % of lithotripsy and 2 % percutaneous cases . Morbidity was low overall and did not differ significantly between the groups ( percutaneous stone removal 22 % , shock wave lithotripsy 11 % , p = 0.087 ) . In the shock wave lithotripsy group there was no difference in lower pole anatomical measurements between kidneys in which complete stone clearance did or did not occur . CONCLUSIONS Stone clearance from the lower pole following shock wave lithotripsy is poor , especially for stones greater than 10 mm . in diameter . Calculi greater than 10 mm . in diameter are better managed initially with percutaneous removal due to its high degree of efficacy and acceptably low morbidity PURPOSE We compared the long-term impact on renal function after shock wave lithotripsy , percutaneous nephrolithotomy or the 2 techniques combined in patients with a solitary kidney . MATERIAL S AND METHODS A total of 45 women and 38 men 15 to 86 years old ( mean age 56.1 ) with a solitary kidney were treated with shock wave lithotripsy ( 53 ) , percutaneous nephrolithotomy ( 18 ) or the 2 techniques combined ( 12 ) . Before and after treatment serum creatinine , blood pressure and the calculated glomerular filtration rate were determined , and raw and calculated data were compared by the Kruskal-Wallis , Fisher exact and Wilcoxon rank sum tests , and the Spearman correlation coefficient . Followup was 1 to 166.5 months ( mean 53.0 , median 46.9 ) overall and statistically equivalent in the 3 treatment arms . RESULTS Treatment groups were comparable in regard to patient age , sex distribution , weight , blood pressure and pretreatment serum creatinine . There was no significant difference in any evaluated pretreatment or posttreatment parameters and no difference in the change in any parameter after treatment . Stratifying patients to pretreatment serum creatinine less or greater than 2 m 
    Output:
    
Results from five small studies , with low method ological quality , indicated ESWL is less effective for kidney stones than PCNL but not significantly different from RIRS .
Hospital stay and duration of treatment was less with ESWL .