Roland Ugarte

A high-efficiency microwave thermoablation system for the treatment of benign prostatic hyperplasia : Results of a randomized, sham-controlled, prospective, double-blind, multicenter clinical trial

OBJECTIVES To determine the effectiveness, safety, and impact on patient quality of life (QOL) of a novel transurethral microwave thermoablation system for the treatment of benign prostatic hyperplasia (BPH). METHODS A total of 169 patients with BPH were randomized to undergo a 1-hour microwave (n = 125) or sham (n = 44) procedure using the Urologix Targis thermoablation system on an outpatient basis, without general or regional anesthesia. Symptoms, flow rates, and QOL scores were determined before the study procedure and periodically thereafter up to 6 months. RESULTS Mean American Urological Association (AUA) score in the microwave group diminished 50% (P <0.0005) by the 6-month evaluation (10.5, 95% confidence interval [CI] 9.2 to 11.8) compared with baseline values (20.8, 95% CI 19.8 to 21.9). The sham group also exhibited lower postprocedural AUA scores; however, the magnitude of the postprocedural decline in AUA score in the microwave group was significantly greater (P <0.01) than that in the sham group. Half the microwave group had an AUA score of less than 9 by 6 months, and the decrease in symptoms was similar among patients with initially moderate versus initially severe symptoms. Mean peak urinary flow rate (Qmax) in the microwave group increased 51% (P <0.0005) by 6 months to 11.8 mL/s (95% CI 10.7 to 13.0) versus a pretreatment value of 7.8 mL/s (95% CI 7.4 to 8.2). The magnitude of the postprocedural increase in Qmax was significantly greater in the microwave than the sham group (P <0.05). In nearly half the microwave group (47%), Qmax increased 50% or more by 6 months compared with 24% of the sham group. Microwave treatment resulted in a significantly greater (P <0.05) positive impact on patient QOL than did the sham procedure. By 6 months, the QOL score in microwave-treated patients (2.2, 95% CI 1.9 to 2.4) averaged 48% lower (P <0.0005) than that at baseline (4.2, 95% CI 4.0 to 4.4). Significantly greater durability of treatment effects was also evident with microwave than with sham treatment, as judged by the higher proportion of microwave-treated patients (98.4%) requiring no further treatment during the 6-month study period versus 83.3% of sham control patients (P <0.0005). Microwave treatment was well tolerated, and complications were generally minor, readily manageable, and transitory. CONCLUSIONS The microwave thermoablation system proved to be an effective and safe treatment modality for BPH, with a positive impact on patient QOL.

Shock wave lithotripsy not associated with development of diabetes mellitus at 6 years of follow-up.

OBJECTIVES To investigate the hypothesis that extracorporeal shock wave lithotripsy (ESWL) increases the incident risk of new-onset diabetes mellitus (DM). Studies have suggested that ESWL predisposes to DM. METHODS Using a mail survey, we collected data on the presence and onset of DM in 1947 patients treated with the Medstone-STS electrohydraulic lithotripter from 1999 to 2002. These patients were matched by age, sex, and body mass index to controls from the National Health and Nutrition Examination Survey (NHANES) database. Of the 1947 patients, 4% could not be matched and were excluded, leaving 1869 for analysis, of whom 60.0% were men. The mean age was 51.9 years at ESWL and the median follow-up was 6 years. The mean body mass index at the end of the study was 28.6 kg/m(2). RESULTS At ESWL, 8.67% of matched patients had a diagnosis of DM. This had increased to 13.9% at the time of survey. In the NHANES group, 8.34% had DM at the time the ESWL group underwent treatment, and this had increased to 14.1% at the NHANES survey. Therefore, the rate of new DM cases in the ESWL group was similar to that in the NHANES group (5.2% vs 5.8%, respectively; P = .47). Multivariate analysis of the patient cohort confirmed that age, sex, body mass index, and family history correlated with development of DM and that the laterality of treatment and number of treatments or shocks given were not significant predictors of DM. CONCLUSIONS The results of our study have shown that patients treated with ESWL do not develop DM at a greater rate than does the general population at 6 years of follow-up.

Shock Wave Lithotripsy Associated With Greater Prevalence of Hypertension

OBJECTIVES To determine whether shock wave lithotripsy (SWL) increases the prevalence of hypertension (HTN) at intermediate follow-up. METHODS All patients were treated with the Medstone STS electrohydraulic lithotripter, and the data were recorded prospectively in a centralized database. The data on the development of HTN after SWL was obtained from a questionnaire mailed to the patients who had undergone SWL from November 1999 and January 2002. Controls matched for age, sex, and body mass index were obtained from the National Health and Nutrition Examination Survey, using the demographic, body measurements, medical conditions, and blood pressure data sets. Two sets of matching controls were used to compare the prevalence of HTN between our patients and the NHANES population at SWL and at the follow-up point. RESULTS A total of 2041 patients responded to the questionnaire, with a median follow-up of 6 years. No statistically significant difference was found in the HTN prevalence between the patients and matched controls at SWL (26.7% vs 28.0%). At the follow-up point, the prevalence of HTN was greater in our patients (37.8%) than in the controls (32.5%, P=.0009). Of our patients, 15% have developed de novo HTN compared with the predicted rate of 6.25% from the matched controls. Male gender, age, and a greater body mass index were associated with the development of HTN, but none of the SWL parameters (number of shocks, bilateral vs unilateral, and multiple SWL sessions) were significantly associated with HTN. CONCLUSIONS The results of our study have indicated a small, but significant, increase in the risk of developing HTN after SWL using a third-generation electrohydraulic lithotripter at intermediate follow-up.

The effectiveness of shock wave lithotripters: a case matched comparison.

PURPOSE We compared the results of shock wave lithotripsy with a newer electromagnetic lithotripter to those of an electrohydraulic lithotripter using identical treatment and followup criteria. MATERIALS AND METHODS We performed a case matched comparison of 8,565 patients treated from 2003 to 2007 using the Medstone STS™ and the Modulith® SLX machines, matching for stone size, location and patient body mass index. The outcome of interest was treatment success in producing stone-free status. We report treatment characteristics, such as stone site and size, gating and final stone-free rate. Significance was considered at p<0.05. RESULTS Overall Modulith SLX and Medstone STS stone-free rates were equivalent (61.1% and 64.5%, respectively, p=0.0664). Matching and logistic regression results showed that differences in the stone-free rate were insignificant for all stones (p>0.7592), lower pole kidney stones (p=0.9659) and ureteral stones (p=0.6409). Medstone STS performed better than Modulith SLX only for distal ureteral stones (83.63% vs 66.67%, p=0.0154). The rate of post-lithotripsy secondary procedures was equivalent (p=0.2079). The difference was insignificant for harder stones (p=0.2988). CONCLUSIONS Shock wave lithotripsy is equally effective using Medstone STS and Modulith SLX for different stone sizes and most stone sites. Shock wave lithotripsy is more successful for lower ureteral stones using the Medstone STS. To our knowledge this is the first study comparing these 2 commonly used lithotripters.

Stone Size is Only Independent Predictor of Shock Wave Lithotripsy Success in Children: A Community Experience

PURPOSE We determined whether age, gender, body mass index, number of stones, stone location or total stone diameter could independently predict stone-free rates after extracorporeal shock wave lithotripsy in children. MATERIALS AND METHODS We reviewed 149 patients 3 to 17 years old undergoing shock wave lithotripsy between 2001 and 2008. Cases were retrieved from a regional shock wave lithotripsy database. Variables analyzed included age, gender, body mass index, number of shocks delivered, stone location, number of stones and total stone diameter. Stone-free status on followup imaging at 2 weeks to 3 months was considered a successful outcome. RESULTS Of 149 patients 32 had multiple stones. After shock wave lithotripsy 106 patients (71%) were stone-free, 12 (8%) required a repeat procedure and 31 (21%) had residual fragments. Number of stones per patient ranged from 1 to 18 (mean +/- SD 2.14 +/- 2.60). Mean +/- SD number of stones was 1.87 +/- 2.42 in successfully treated patients and 2.81 +/- 2.92 in those with treatment failure (p = 0.065). Total stone diameter ranged from 2 to 90 mm (mean +/- SD 14.03 +/- 16.68). Mean total stone diameter was 11.1 +/- 13.4 mm in successfully treated patients and 21.3 +/- 21.4 mm in those with treatment failure (p <0.005). CONCLUSIONS To our knowledge we present the first multi-institutional cohort study in children demonstrating no significant relationship between successful outcome and patient age, gender, body mass index, stone location or number of stones. Only total stone diameter independently predicted shock wave lithotripsy success.

Extracorporeal Shock Wave Lithotripsy Induced Stimulation of the Obturator Nerve

Extracorporeal shock wave lithotripsy to a left lower third ureteral calculus, 1.4 x 0.9 cm. large, using an unmodified Dornier HM3* lithotriptor with the patient in the sitting position produced thigh adductor movement with each shock. The procedure was terminated. Extracorporeal shock wave lithotripsy was performed uneventfully 1 week later using a Medstone STS lithotriptor with the patient in the supine position. We believe that the sitting position caused increased intra-abdominal pressure in the pelvis resulting in apposition of the ureteral segment containing the calculus to the obturator nerve, which was included either in the second focal point or in the extended shock path of the Dornier HM3 unit.

Eighteen-year experience with the Medstone STS lithotripter: safety, efficacy, and evolving practice patterns.

OBJECTIVE To evaluate trends in safety, efficacy, and practice patterns for shockwave lithotripsy (SWL) procedures performed during a 18-year period and correlate the findings with recent evidence-based practice guidelines. MATERIALS AND METHODS From January 1988 to June 2006, 66,819 SWLs were performed using the Medstone STS lithotripter in patients with radiologic evidence of stones in the kidney or ureter. Treatment characteristics, such as stone location and size, need of re-treatment, and final success rate were recorded. The procedures were further divided by year for statistical consideration. Statistical analysis was performed using Student t test; P < 0.05 was considered significant. RESULTS Overall SWL success rate was 85% (39,667/46,669), and the overall re-treatment rate was 7.2% (3,417/46,669). There was no significant change in the overall proportion of lower-pole calculi managed with SWL, although there was a significant decrease in the proportion of SWL used for lower calix stones larger than 16 mm in the time period after 2000 (P = 0.006). There was a steady increase in the number of procedures performed for renal calculi in other locations per year, in particular for intrarenal calculi smaller than 20 mm. Intrarenal stones larger than 30 mm decreased as a proportion of procedures per year (P = 0.048) There was no significant change in the proportion of upper and distal ureteral stones managed, corresponding to a solid plateau in the percentage of SWL performed per year. CONCLUSION Our study did not demonstrate an overall drop in SWL; however, it did show the interference of endoscopic procedures on two case scenarios. There was a significant decrease (P = 0.048) in SWL for renal stones larger than 30 mm, and the same trend was noted for lower calix stones larger than 15 mm (P = 0.06).