Outcome Of Shock Wave Lithotripsy Research Articles

Preoperative Nomograms for Predicting Stone-Free Rate After Extracorporeal Shock Wave Lithotripsy

Extracorporeal shock wave lithotripsy is currently accepted as a first line treatment modality for urolithiasis. In obtaining informed consent it is important to inform patients of the stone-free rate with extracorporeal shock wave lithotripsy before surgery. The present study was performed to develop preoperative nomograms for predicting stone-free rates after extracorporeal shock wave lithotripsy. A total of 435 patients with 507 urinary stones were treated with extracorporeal shock wave lithotripsy with a Dornier Lithotripter D. Patient age, sex, body mass index, number of stone(s) in each treatment, stone length, side and location were evaluated before extracorporeal shock wave lithotripsy, and treatment efficacies were evaluated at 3 months after each session. The treated stones were divided into 2 groups, those in cases that were stone-free with a single extracorporeal shock wave lithotripsy session and those in all other cases. Multivariate analysis was performed using a logistic regression model. The nomograms were developed by repeating the analysis on 200 bootstrap samples. Stone length, location and number were identified as significant variables on multivariate analysis, and a logistic regression model was developed using these variables. The nomograms predicting stone-free rate at 3 months after single extracorporeal shock wave lithotripsy treatment were finally developed from 200 bootstrap samples. In these nomograms the stone-free probability was highest for solitary proximal ureteral stones less than 5 mm in size (93.8%) and lowest for multiple caliceal stones greater than 21 mm (10.5%). This study demonstrated that stone size, location and number are significant predictors of extracorporeal shock wave lithotripsy outcome. We have developed nomograms for predicting the stone-free rate of extracorporeal shock wave lithotripsy, which is useful for counseling patients with urolithiasis before surgery.

Rapid Communication: First Clinical Experience with Doli S 220F-XP Extracorporeal Lithotripter for Urinary Lithiasis

To assess the initial results of the Dornier Doli S 220F-XP extracorporeal lithotripter for the management of solitary urinary calculi. We prospectively examined the outcome of shockwave lithotripsy (SWL) in the first 140 patients with solitary renal and ureteral lithiasis treated by one urologist with the new power Doli S lithotripter. Ninety-one patients (group A) had renal stones, and 49 patients (group B) had ureteral stones. Data were collected with respect to stone size, location, and fragmentation. In group A, clinical success was documented in 77 patients (84%) at 1 month after lithotripsy. Three months after lithotripsy, 69 patients (75.2%) were stone free and 8 (8.8%) had fragments <4 mm. In group B, 41 patients (83%) achieved clinical success 1 month after lithotripsy. Thirty-eight patients (77%) were stone free 3 months after treatment, and 3 (6%) had fragments <4 mm. Seven patients (7%) in group A and three patients (6%) in group B required re-treatment. The overall efficiency quotient was 67%. No patient developed a perinephric hematoma. Ninety-four percent of the patients reported mild pain during lithotripsy. The majority (91%) mentioned that they were satisfied with this treatment modality for urinary lithiasis (mean visual analog scale satisfaction score 8). The Doli S 220 F-XP is a safe and effective device for managing calculi throughout the urinary tract.

Diabetes Mellitus and Hypertension Associated With Shock Wave Lithotripsy of Renal and Proximal Ureteral Stones at 19 Years of Followup

SWL has revolutionized the management of nephrolithiasis and it is a preferred treatment for uncomplicated renal and proximal ureteral calculi. Since its introduction in 1982, conflicting reports of early adverse effects have been published. However, to our knowledge the long-term medical effects associated with SWL are unknown. We evaluated these adverse medical effects associated with SWL for renal and proximal ureteral stones. Chart review identified 630 patients treated with SWL at our institution in 1985. Questionnaires were sent to 578 patients who were alive in 2004. The response rate was 58.9%. Respondents were matched by age, sex and year of presentation to a cohort of patients with nephrolithiasis who were treated nonsurgically. At 19 years of followup hypertension was more prevalent in the SWL group (OR 1.47, 95% CI 1.03, 2.10, p = 0.034). The development of hypertension was related to bilateral treatment (p = 0.033). In the SWL group diabetes mellitus developed in 16.8% of patients. Patients treated with SWL were more likely to have diabetes mellitus than controls (OR 3.23, 95% CI 1.73 to 6.02, p <0.001). Multivariate analysis controlling for change in body mass index showed a persistent risk of diabetes mellitus in the SWL group (OR 3.75, 95% CI 1.56 to 9.02, p = 0.003). Diabetes mellitus was related to the number of administered shocks and treatment intensity (p = 0.005 and 0.007). At 19 years of followup SWL for renal and proximal ureteral stones was associated with the development of hypertension and diabetes mellitus. The incidence of these conditions was significantly higher than in a cohort of conservatively treated patients with nephrolithiasis.

Extracorporeal Shock Wave Lithotripsy in the Treatment of Proximal Ureteral Stones: Does the Presence and Degree of Hydronephrosis Affect Success?

ObjectivesWe investigated the relation between the presence and degree of stone induced hydronephrosis and the outcome of extracorporeal shock wave lithotripsy (SWL) in patients with solitary proximal ureteral stones. Methods130 patients with or without hydronephrosis were treated with SWL. The degree of hydronephrosis was defined by renal ultrasound. Patients were divided into four groups according to the degree of stone induced hydronephrosis. Group 0 (24%) had no urinary system dilatation, group 1 (31.2%) had a mild dilatation of the renal pelvis, group 2 (40%) had a moderate and group 3 (4.8%) a severe dilatation of the renal pelvis and calices. The stone size, number of shock waves applied and number of sessions required to achieve stone clearance were recorded. ResultsMean stone size was 8.2mm±2.5mm. Mean time to stone clearance was 13.7 days±16.3. In 74.4% of patients stone clearance was observed. Additional 4.8% harbored residual fragments ≤3mm after 3 months. Differences among the four groups in terms of stone size, time to stone clearance and treatment failure were not significant. ConclusionsThe presence or degree of hydronephrosis caused by a proximal ureteral stone does not affect the time to stone clearance or success rate after SWL.

Outcomes of Shockwave Lithotripsy for Upper Urinary-Tract Stones: A Large-Scale Study at a Single Institution

We investigated the risk factors having an impact on the achievement of stone-free status and on the success rate, as well as on the likelihood of recurrence, in patients undergoing shockwave lithotripsy. We evaluated the characteristics and outcomes of 3023 patients (3254 renal units) with upper urinary-tract stones who underwent SWL at the Funabashi Clinic over a 13-year period. We assessed the stone-free and success rates for 2844 patients (3061 renal units) 3 months post-SWL. We also determined the recurrence rate for the 1078 patients (1139 renal units) who had achieved stone-free status at that time. Overall, stone-free status was achieved in 65.1% of patients, and the success rate was 85.7%. There were significant differences in the stone-free rates depending on patient age, history of urolithiasis, and presence of pyuria before SWL, as well as the number, location, size, and composition of the stones. Stones recurred in 326 of 1139 renal units (28.6%) during a mean follow-up of 36 months. The recurrence rates were 7.5%, 24.1%, and 33.0% after 1, 3, 5 years, respectively. Multiple stones, a history of urolithiasis, and stones located in the kidney or both kidneys plus the ureter significantly influenced recurrence. Multivariate analysis demonstrated that multiple stones were most significantly related to recurrence. Treatment with SWL has a low morbidity and high effectiveness. The number and location of stones and a history of urolithiasis significantly influence recurrence. Further studies of prophylactic therapy are required, especially for patients with these factors.

Role of computed tomography with no contrast medium enhancement in predicting the outcome of extracorporeal shock wave lithotripsy for urinary calculi

BJU InternationalVolume 96, Issue 4 p. 685-686 Role of computed tomography with no contrast medium enhancement in predicting the outcome of extracorporeal shock wave lithotripsy for urinary calculi Zubayr R. Zaman, Zubayr R. Zaman St. Anthony's Hospital, Surrey, and St. George's Hospital, London, UKSearch for more papers by this authorSashi S. Kommu, Sashi S. Kommu St. Anthony's Hospital, Surrey, and St. George's Hospital, London, UKSearch for more papers by this authorNicholas A. Watkin, Nicholas A. Watkin St. Anthony's Hospital, Surrey, and St. George's Hospital, London, UKSearch for more papers by this author Zubayr R. Zaman, Zubayr R. Zaman St. Anthony's Hospital, Surrey, and St. George's Hospital, London, UKSearch for more papers by this authorSashi S. Kommu, Sashi S. Kommu St. Anthony's Hospital, Surrey, and St. George's Hospital, London, UKSearch for more papers by this authorNicholas A. Watkin, Nicholas A. Watkin St. Anthony's Hospital, Surrey, and St. George's Hospital, London, UKSearch for more papers by this author First published: 11 August 2005 https://doi.org/10.1111/j.1464-410X.2005.05788_2.xCitations: 2Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume96, Issue4September 2005Pages 685-686 RelatedInformation

Role of computed tomography with no contrast medium enhancement in predicting the outcome of extracorporeal shock wave lithotripsy for urinary calculi

BJU InternationalVolume 96, Issue 4 p. 685-685 Role of computed tomography with no contrast medium enhancement in predicting the outcome of extracorporeal shock wave lithotripsy for urinary calculi Chi-Fai Ng, Chi-Fai Ng The Urology Division, Department of Surgery, The Chinese University of Hong Kong, Hong Kong, ChinaSearch for more papers by this authorChi-Wai Cheng, Chi-Wai Cheng The Urology Division, Department of Surgery, The Chinese University of Hong Kong, Hong Kong, ChinaSearch for more papers by this author Chi-Fai Ng, Chi-Fai Ng The Urology Division, Department of Surgery, The Chinese University of Hong Kong, Hong Kong, ChinaSearch for more papers by this authorChi-Wai Cheng, Chi-Wai Cheng The Urology Division, Department of Surgery, The Chinese University of Hong Kong, Hong Kong, ChinaSearch for more papers by this author First published: 11 August 2005 https://doi.org/10.1111/j.1464-410X.2005.05788_1.xCitations: 2Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature Volume96, Issue4September 2005Pages 685-685 RelatedInformation

Role of computed tomography with no contrast medium enhancement in predicting the outcome of extracorporeal shock wave lithotripsy for urinary calculi

To evaluate the usefulness of urinary calculi attenuation values from non-contrast computed tomography (NCCT) in predicting the outcome of treatment by extracorporeal shock wave lithotripsy (ESWL). We evaluated 112 patients with solitary renal and upper ureteric calculi of 0.5-2 cm undergoing ESWL. All patients had NCCT at 120 kV and 240 mA on a spiral CT scanner. During each ESWL session 3000 shock waves were given to a maximum of 3.0 kV. A final X-ray of the kidney, ureters and bladder was taken 12 weeks after the last ESWL session. Fragments of < or = 5 mm were regarded as clinically insignificant residual fragments (CIRF). The calculi retrieved were analysed by X-ray diffraction and the results assessed by comparing the mean density (as measured in Hounsfield units, HU) with the number of ESWL sessions and clearance. In all, 82 (76%) patients had complete clearance of stones and 26 (24%) had CIRF. There was a linear relationship between the calculus density and number of ESWL sessions required. Of patients with calculi of < or = 750 HU, 41 (80%) needed three or fewer ESWL sessions and 45 (88%) had complete clearance. Of patients with calculi of > 750 HU, 41 (72%) required three or more ESWL sessions, and 37 (65%) had complete clearance. The best outcome was in patients with calculus diameters of < 1.1 cm and mean densities of < or = 750 HU; 34 (83%) needed three or fewer ESWL sessions, and the clearance rate was 90%. The worst outcome was in patients with calculus densities of > 750 HU and diameters of > 1.1 cm; 23 (77%) needed three or more ESWL sessions and the clearance rate was only 60%. The calculus density was a stronger predictor of outcome than size alone. The use of NCCT for determining the attenuation values of urinary calculi before ESWL might help to predict the treatment outcome, and so might help in planning alternative treatment in patients with a likelihood of a poor outcome from ESWL.

Is stone radiodensity a useful parameter for predicting outcome of extracorporeal shockwave lithotripsy for stones &lt; 2 cm?

Several factors determine the success of extracorporeal shockwave lithotripsy (SWL) for kidney stones: stone size, stone location within the collecting system, stone type, and the SWL machine used. It has been suggested that stone radiodensity, as determined either by plain radiography or computed tomography attenuation values, may be an independent predictor of SWL success. We examined the outcome of SWL for solitary stones less than or equal to 2 cm located within the renal pelvis, based on their radiodensity. 211 patients with solitary renal pelvic stones measuring less than or equal to 2 cm were treated on a Dornier Doli 50 lithotriptor under general anesthesia. The radiodensity of the stone was determined to be either less than, equal to, or greater than the radiodensity of the ipsilateral 12th rib. Stone-free rates (SFR) were determined at 3 months by kidney, ureters and bladder (KUB) plain X-rays. Patients requiring re-treatment or auxiliary procedures were considered failures of SWL. Follow-up SFR information was available in all 211 patients. Stone composition was available in 158 (75%) treated patients, but no correlation was found between stone radiodensity and stone composition. For stones < or = 10 mm within the renal pelvis, the SFRs were similar (71 to 74% regardless of stone radiodensity). For stones between 11 and 20 mm, the SFR was 60% if the stone had a radiodensity > 12th rib compared to a SFR of 71% if the stone radiodensity was < or = 12th rib. However, these differences in SFRs were not statistically significant. On the Doli machine, stone radiodensity alone does not predict lithotripsy treatment outcome for stones < or = 1 cm within the renal pelvis. This parameter is probably only useful as the stone size becomes larger than 1 cm, and should be used in conjunction with other stone parameters to select appropriate therapy.

Results of shockwave lithotripsy for pediatric urolithiasis.

Shockwave lithotripsy (SWL) is widely practiced in the management of pediatric urolithiasis. However, the efficacy, need for ancillary procedures, and treatment-related complications are not as clearly defined as in the adult population. We reviewed the outcomes of SWL in the pediatric population at our lithotripsy unit. A retrospective review of all patients </=16 years of age treated with SWL between January 1991 and June 2002 was undertaken. One hundred patients with 115 stones underwent 131 SWL procedures (115 first treatments, 16 retreatments). The mean age was 10.7 years (range 10 months-16 years). Stone locations were as follows: caliceal 42.6%, renal pelvic 27%, and ureteral (30.4%). The mean stone size was 7.8 mm (range 2-23 mm). Risk factors for stone formation, the need for secondary therapies, and treatment-related complications were noted. The stone-free rate for a single-session SWL procedure, defined as complete absence of stone fragments on plain film, intravenous urography, or renal ultrasonography, was calculated based on 3-month follow-up. The efficiency quotient (EQ) was also calculated. Risk factors were identified in 31 children (27.0%), including metabolic and anatomic abnormalities. Patients with a risk factor were less likely to be stone free after one SWL session than those without risk factors (31.7% v 64.7%; P < 0.001). General (74.8%), neurolept (24.4%), and epidural (0.8%) anesthesia were utilized. Ureteral stents were placed in 25% of treatments. There were no intraoperative complications. Minor complications were seen in 4.6% of patients. Ancillary procedures were required in 10 patients. Following initial SWL treatment, 60.2% of patients were stone free. The retreatment rate was 13.9%. Following a second treatment, the stone-free rate increased to 68%. The EQ was 54.3. Employing a strict definition of treatment success, single-session SWL in our series offers moderate efficacy in the pediatric population. Patients who have a large stone or risk factor such as an anatomic abnormality are less likely to become stone free and might better undergo an endourologic procedure.

Outcome and Safety of Extracorporeal Shock Wave Lithotripsy as First-Line Therapy of Lower Pole Nephrolithiasis

Introduction: The aim of this study is to assess the efficiency of extracorporeal shock wave lithotripsy (ESWL) as initial therapy for isolated lower pole kidney stones smaller than 20 mm. Patients and Methods: During a 24-month period 116 patients with previously untreated single stones under 20 mm in diameter were treated with a Dornier lithotripter S. They were analyzed with regard to stone site and size, number of ESWL sessions, auxiliary measures, retreatment rates, complications and the time taken for stone clearance. Results: 76 patients (65.5%) became stone free, 50 of them (43.1%) within 3 months after ESWL. Depending on stone size the stone-free rates were 67.1% for patients with a stone diameter of <10 mm (59 of 88 patients), and 60.7% for stone diameters between 10 and 20 mm (17 of 28 patients). Complications during and after treatment were rare, i.e. the necessity of ureteral stent insertion due to colic (n = 10), endoscopic stone removal (n = 2), acute pyelonephritis (n = 1), stonestreet (n = 1) and 1 case of hematoma not requiring intervention. The recurrence rate during follow-up (13.2–36.9, mean 25.0 months) was low: 16 patients (13.8%) had recurrent or persistent stones, and 74 patients (63.8%) had no evidence of urolithiasis. Conclusions: ESWL is a safe and efficient first-line therapy for treatment of isolated small lower pole kidney stones with acceptable stone-free rates, low morbidity, few complications and a low stone recurrence rate.

University of Wisconsin experience using the Doli S lithotriptor

ObjectivesTo present our initial results using the Dornier Doli S lithotriptor with the 220 electromagnetic shock wave emitter to treat urinary calculi. At present, there is no published report of the efficacy of this instrument in service in the United States. MethodsWe retrospectively reviewed the outcome of shock wave lithotripsy in 270 consecutive patients with solitary renal and/or ureteral stones treated from September 1998 to October 2001 with the Dornier Doli S lithotriptor. Data were collected with respect to stone size, location, and fragmentation. ResultsOf the 270 patients treated, 204 had renal stones and 66 had ureteral stones. All patients had solitary stones. The renal stones averaged 9.7 mm in size (range 4 to 26). The ureteral stones averaged 7.8 mm (range 4 to 17). Of the renal stones, 51% were located in the renal pelvis, with 18%, 5%, and 25% located in the upper, middle, and lower poles, respectively. Of the ureteral stones, 68% were located in the proximal ureter, with 14% and 18% in the mid and distal ureter, respectively. In the renal group, 176 (86%) of 204 patients achieved clinical success. Of these patients, 148 were stone free (73%) and 28 had residual fragments less than 4 mm in size (14%). In the ureteral group, 52 (79%) of 66 patients achieved clinical success. Of these patients, 50 were stone free (76%) and 2 (3%) patients had fragments less than 4 mm in size. Thirteen (6%) of 204 patients in the renal group required retreatment. Four (6%) of 62 patients in the ureteral group required retreatment. Of the patients in whom treatment failed and who had stone analysis, 16 (76%) of 21 had stones composed of predominantly calcium oxalate monohydrate. Four patients developed steinstrasse. Two were treated with retrograde stent placement, and the other two with placement of percutaneous nephrostomy. One patient developed a known perinephric hematoma but did not require a blood transfusion. ConclusionsShock wave lithotripsy using the Doli S in appropriately selected patients is an effective instrument for treating urinary calculi throughout the urinary tract.

Prediction of Lower Pole Stone Clearance After Shock Wave Lithotripsy Using an Artificial Neural Network

We performed this study as a comprehensive evaluation of variables reported to affect lower pole stone clearance after shock wave lithotripsy using artificial neural network analysis. The radiographic images and treatment records of 680 patients with lower pole renal calculi treated with primary shock wave lithotripsy using the Wolf Piezolith 2500 (Wolf, Knittlingen, Germany) lithotriptor were retrospectively evaluated by applying artificial neural network analysis. Successful stone clearance was defined as absent fragments of any size detected on plain x-ray with tomography and/or excretory pyelography performed 6 months after treatment. Prognostic variables included patient characteristics, laboratory values, stone characteristics and the spatial anatomy of the lower pole, as defined by infundibular length, diameter, caliceal pelvic height, 2 measurements of the lower infundibulopelvic and infundibuloureteropelvic angles as well as the pattern of dynamic urinary transport. Artificial neural network analysis had 92% accuracy for correctly predicting lower pole stone clearance. The pattern of dynamic urinary transport represented the most influential predictor of stone clearance, followed by a measure of the infundibuloureteropelvic angle, body mass index, caliceal pelvic height and stone size. Anatomical measurements of lower pole anatomy and classification of the type of urinary transport were well reproducible with low intra-observer and interobserver variability (correlation coefficient alpha >0.8). In a comprehensive analysis of variables reported to influence lower pole stone clearance artificial neural network analysis predicted stone clearance with a high degree of accuracy. The relative importance of dynamic urinary transport in lower pole stones and the usefulness of artificial neural network analysis to predict shock wave lithotripsy outcomes in individuals must be confirmed in a prospective trial.

Morphology of renal pelvis and clearance of lower pole stones following ESWL

A prerequisite for successful outcome of exatracorporeal shock wave lithotripsy (ESWL) is effective stone fragmentation. Despite successful stone fragmentation, complete clearance of stone fragments cannot be achieved in every patient, due to various factors. The aim of this prospective study was to determine morphological factors that affect clearance following successful stone fragmentation by ESWL. In the period October 1999 and January 2001, 60 patients (45 male and 15 female) with single lower pole kidney stones have been treated using lithotripter Lithostar 2000TM. Parameters of radiographic anatomy, measured on intravenous pyelography, included infundibular width and length, infundibuloureteral infundibulopelvic angles. After the follow-up period of 3 months, patients were divided into two groups regarding clearance status: Group I consisted of stone free patients, and group II of those with residual fragments. Average values of measured parameters in group I vs group II were as follows: infundibular length 27.70 +/- 5.48 mm vs 30.25 +/- 3.95 mm (p = 0.045, Mann-Whitney test); infundibular width 5.98 +/- 3.28 mm vs 4.70 +/- 1.30 mm (p = 0.018, Mann-Whitney test); infundibulopelvic angle 52.92 +/- 20.76 degrees vs 34.10 +/- 8.19 degrees (p = 0.00001, Mann-Whitney test); infundibuloureteral angle 48.00 +/- 21.13 degrees vs 30.70 +/- 7.49 degrees (p = 0.00001, Mann-Whitney test). This study revealed that parameters of infundibulopelvic anatomy were significantly different in the examined groups. The success of clearance of fragments following ESWL procedure can be predicted using these morphologic parameters.

Evaluation Of Disintegration In Prevesical Ureteral Calculi By 3-Dimensional Endo-Ultrasound With Surface Rendering

Lower ureteral calculi are accessible by transrectal endo-ultrasound, including 3-dimensional image processing with surface rendering. We analyzed the efficiency of this innovative technology compared with that of standard radiographic examinations with respect to the outcome of extracorporeal shock wave lithotripsy (ESWL) (Dornier Medical Systems, Marietta, Georgia). In patients with prevesical or intramural calculi we performed excretory urography and transrectal endo-ultrasound using a Combison 530 device (Kretz Technik, Zipf, Austria) with integrated optional 3-dimensional image processing and surface rendering. A total of 102 ESWL cases (108 radiopaque stones, 145 ESWL sessions) were included in the study. One day after ESWL an evaluation was independently performed by a radiologist (plain x-ray) and a urologist (transrectal endo-ultrasound). Results were compared to the outcome determined during further followup. All stones were evaluable by endo-ultrasound with surface rendering, whereas in 27 cases the stone was hidden by extraureteral processes on followup radiography. Immediately after endo-ultrasound 8 calculi were passed. In 7 of the remaining 110 cases (6.4%) radiographic examination did not confirm sonographic findings. In these cases evaluation by surface rendering proved to be correct on followup. Endo-ultrasound with surface rendering proved to be highly effective for evaluating ESWL success in cases of prevesical ureteral stones. This technique is independent from bowel gas or other factors that impede radiological imaging. It is safe, easy to learn, well tolerated by patients and does not expose them to radiation.

Factors associated with failure of extracorporeal shock-wave lithotripsy for ureteral stones using Dornier lithotripter U/50.

In the present series of 170 patients who underwent extracorporeal shock-wave lithotripsy (SWL) treatment for ureteral stones, the authors determine which patients with ureteral stones had an unsuccessful outcome. The records of 170 patients with ureteral stones who were treated with SWL using the Dornier lithotriptor U/50 (EMSE 140) between January 1998 and December 1999 were retrospectively investigated. One hundred and thirty-one patients were treated with SWL alone (single session, n = 98; multiple session, n = 33) and 39 patients required auxiliary treatment due to failure of SWL (33 with transurethral ureterolithotripsy (TUL), one with open lithotomy, and five with residual fragments who were followed up). These two groups were compared using multivariate logistic regression analysis. Lower ureteral stones and stones more than 12 mm in diameter were associated with a poor outcome of SWL. There were no significant differences in age, gender, number of stones, JJ stent placement, and degree of ureteral obstruction due to the stone between the two groups. The odds ratios of lower ureteral stones and stones > or = 12 mm were 4.18 and 2.57, respectively. Patients with distal ureteral stones and/or stones more than 12 mm in diameter were difficult to treat successfully with SWL. Alternatives such as TUL should possibly be considered as a first-line therapy for these stones.

Is there a simpler method for predicting lower pole stone clearance after shockwave lithotripsy than measuring infundibulopelvic angle?

Several anatomic factors influence the clearance of lower pole stones treated with shockwave lithotripsy (SWL). One of these is the infundibulopelvic angle, but its measurement is complex. We proposed a more simple measure of caliceal dependence, the caliceal pelvic height (CPH), which we defined as the distance between a horizontal line from the lowermost point of the calix containing the stone to the highest point of the lower lip of the renal pelvis. In 62 patients who had SWL for solitary lower pole stones, a CPH < 15 mm was associated with a stone clearance rate of 92%, whereas with a CPH > or = 15 mm, the clearance rate was only 52% (p < 0.05). A majority (74%) of the patients with an infundibular width of > or = 5 mm were rendered stone free compared with 40% of those with a width of < 5 mm (p < 0.05). Measurement of the CPH, in conjunction with other anatomic factors, may more accurately predict the outcome of SWL in patients with lower pole stones.

Long-term Radiographic and Functional Outcome of Extracorporeal Shock Wave Lithotripsy Induced Perirenal Hematomas

Purpose We determined the long-term radiographic and functional outcome of extracorporeal shock wave lithotripsy (ESWL † † Dornier Medical Systems, Inc., Marietta, Georgia. ) related perirenal hematomas. Materials and Methods We followed 19 patients with 21 ESWL induced hematomas for 4 to 61 months (mean 19.6) after ESWL with serial ultrasound, blood pressure and serum creatinine determinations. Results Complete radiographic resolution of the hematoma was evident in 18 cases (85.7 percent), while 2 (9.5 percent) were significantly smaller and 1 (4.8 percent) remained unchanged. Of 10 patients who were normotensive before ESWL none experienced sustained new onset hypertension. Of 9 patients with preexisting hypertension none had a sustained exacerbation. Finally, during followup serum creatinine levels overall remained unchanged from pre-ESWL values. Conclusions We conclude that, by far, the most likely outcome for patients with ESWL related hematomas is spontaneous radiographic resolution within 2 years without clinically evident adverse effects on blood pressure or renal function.

Role of Metabolic Evaluation and Specific Prophylaxis in the Long-Term Outcome of Extracorporeal Shock Wave Lithotripsy in Children*

Children (28 boys, 24 girls) with an average age of 10.1 years (range 2–17) who underwent 63 sessions of extracorporeal shock wave lithotripsy for 64 urinary stones (57 renal, 7 ureteral) between 1984 and 1991 have been evaluated with special regard to long-term recurrences and stone regrowth. The first 10 patients were treated on a Dornier HM3, the rest on the Siemens Lithostar. Of the 52 patients, 35 were first-time stone formers, and 17 had recurrent disease. A uniform metabolic evaluation with 24-hour urinalysis was not performed in all patients. Fourteen children received urinary calcium analysis according to Pak's test. After 3 months, 93% were either stone free or had a residual stone mass of less than 3 mm. Within an average follow-up of 39.3 (9–80) months, 74% were stone free, 9.5% had recurrences, and 17% showed regrowth. Only 1 of 16 patients who received specific prophylaxis for hypercalciuria (n = 6), cystinuria (n = 6), or infection stones (n = 4) developed new stone episodes, while the other 10 patients with either recurrence or regrowth belonged to the no-prophylaxis group. We think that all children with urolithiasis should undergo a metabolic evaluation and have specific prophylaxis to enhance the long-term stone-free rate following SWL.

Ureteral Stenting During Extracorporeal Shock Wave Lithotripsy: Help or Hindrance?

We retrospectively reviewed the outcome of extracorporeal shock wave lithotripsy in patients with renal calculi less than 3cm. in size who were treated at a large multi-user lithotripsy center. Patients in whom indwelling ureteral stents were placed before lithotripsy treatment were subjected to higher levels of total power (shocks times voltage), yet the rate free of stones did not differ from those treated without a stent. In addition, the patients with internal ureteral stents experienced a significantly higher incidence of urinary urgency (43 versus 25 per cent) and hematuria (40 versus 23 per cent) than nonstented patients, respectively (p less than 0.05). Also, the duration of bladder discomfort was longer for stented patients (26 versus 13 per cent) as was the duration of urinary frequency (31 versus 16 per cent), compared to nonstented patients (p less than 0.05).The results suggest that use of an indwelling ureteral stent may not contribute to a higher rate free of stones for the treatment of small to medium sized renal calculi and, in fact, it may make the treatment more uncomfortable for the patient than performing lithotripsy without ureteral stenting. Of course, in selected cases (solitary kidney, large stone burden and aid in stone localization) ureteral stenting has a useful adjunctive role in extracorporeal shock wave lithotripsy.