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OBJECTIVE: To standardise infundibular width (IFW) measurement, to determine patient variability, and to determine inter-rater variability on intravenous pyelography (IVP). PATIENTS AND METHODS: Fifty outpatient IVP films were randomly drawn from two hospitals between 1 July 1998 and 31 August 1999, and examined to measure the lower calyceal IFW on the 5, 10 and 20 min films with compression, and after voiding. Kidneys with previous renal surgery, hydronephrosis or renal anatomical anomalies were excluded; in all, 81 kidneys from 50 patients were examined. The IFW was measured at the narrowest point along the infundibulum. All 50 films were then reviewed by two urologists unaware of their origin, to determine the inter-rater reliability of the infundibular measurements. RESULTS: Analysis of variance (anova) with posthoc analysis showed a significant difference in IFW at each phase of the IVP (repeated measures anova, P < 0.001). The mean (95% confidence interval) IFW was greatest on the compression film, at 4.4 (2.6) mm, and least on the postvoid film, at 1.6 (2.1) mm. Overall inter-rater reliability was 0.9780 (intraclass correlation coefficient), and the Pearson correlation between each rater for the IFW at each phase of the IVP was >/= 0.886. CONCLUSIONS: There is wide variability in lower calyceal IFW among the various IVP films in a given study. Thus any predictive value of the IFW must be standardized for the timing and IVP film type (compression, postvoid, etc.). The inter-rater reliability of IFW is high, suggesting that if used correctly it may be more useful in predicting the outcome after shock wave lithotripsy.

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PURPOSE: We compare the effectiveness of mechanical percussion and inversion with observation for eliminating lower caliceal fragments 3 months after shock wave lithotripsy. MATERIALS AND METHODS: At 3 months after shock wave lithotripsy 69 patients with residual lower caliceal fragments 4 mm. or less were randomized to receive either mechanical percussion and inversion or observation for 1 month. The observation group then received crossover mechanical percussion and inversion if fragments persisted. All patients were followed with plain film of the kidneys, ureters and bladder to assess the stone area and stone-free status, and renal tomography or noncontrast spiral computerized tomography to confirm stone-free status. A blinded radiologist reviewed all films. Patients were treated with a mechanical chest percussor applied to the flank while inverted to greater than 60 degrees after receiving 20 mg. furosemide. RESULTS: A total of 35 patients were randomized to receive immediate mechanical percussion and inversion therapy and 34 observation. Of the patients in the observation group 28 subsequently received mechanical percussion and inversion after completing the observation period. The groups were not different in gender, body mass index, side affected, stone location or renal anatomical features. The mechanical percussion and inversion group had a substantially higher stone-free rate than the observation group (40% versus 3%, respectively, p <0.001). The mechanical percussion and inversion group also had a greater improvement in total stone area than controls (-63.3% versus +2.7%, respectively, p <0.001). No significant adverse effects were noted in the mechanical percussion and inversion group. CONCLUSIONS: Mechanical percussion and inversion is a safe and effective treatment option for residual lower caliceal fragments 3 months after shock wave lithotripsy. Nearly 50% of patients become stone-free, and stone burden is decreased by 50% in the remainder.

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BACKGROUND AND PURPOSE: Electrodes used by the Dornier MFL 500 lithotripter have a specified lifespan, after which, the manufacturer recommends replacing the electrode before continuing the treatment. The aim of this study was to investigate whether electrodes continue to function effectively beyond 100% consumption by measuring the pressure output of electrodes up to 300% consumption or until electrode failure. MATERIALS AND METHODS: We assessed new, refurbished, and twice-refurbished electrodes to compare their respective performances. RESULTS: Rather than a decrease, there was a trend toward increased pressure output beyond 100% electrode consumption, with no drop in pressure prior to 300% consumption or electrode failure. All three types of electrodes functioned adequately above 100% consumption. CONCLUSION: These observations suggest that discarding the electrode before the completion of the treatment or electrode failure is not warranted. Using a single electrode rather than multiple electrodes to complete a treatment has the potential to save both time and cost.

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PURPOSE: We determined the number of shock wave lithotripsy treatments that should be given for a single ureteral stone before alternate modalities are used. MATERIALS AND METHODS: We compared the stone-free rate of initial shock wave lithotripsy for ureteral calculi with that of subsequent treatments. We evaluated 1,593 ureteral stones treated with the Dornier MFL 5000 lithotriptor* from January 1, 1994 to September 1, 1999 using various parameters associated with treatment outcome. RESULTS: The stone-free rate after initial treatment was 68% (1,086 of 1,593 stones), which decreased to 46% (126 of 273) after re-treatment 1. We observed a further decrease in the stone-free rate after re-treatment 2 to 31% (19 of 61 stones, p = 0.001). The cumulative stone-free rate increased to 76% (1,212 of 1,593 stones) after 2 treatments and to 77% (1,231 of 1593) after 3. The stone-free rate for stones 10 mm. or less was significantly better than that of stones 11 to 20 mm. initially (64% versus 43%) and after re-treatment (49% versus 37%). A ureteral stent decreased the stone-free rate of initial treatment and re-treatment 1 by 12% and 14%, respectively (p = 0.001). After initial treatment the stone-free rate of the upper and mid ureter was significantly higher than that of the lower ureter. Patient weight had no significant impact on success in either group. CONCLUSIONS: The stone-free rate of re-treating ureteral calculi with shock wave lithotripsy decreases significantly after the initial treatment. These findings imply that ureteroscopic management of ureteral stones may be better than shock wave lithotripsy after initial shock wave lithotripsy fails.

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PURPOSE: To study the effect of altering shockwave frequency on the efficiency of stone fragmentation using the MFL 5000 spark-gap lithotripter. MATERIALS AND METHODS: Standardized solid plaster stones, 12.0 +/- 0.5 mm in diameter, were fragmented at an energy setting of 20 kV. The shockwave frequencies tested were 60, 80, and 117 per minute. Stones were fragmented throughout the entire lifespan of the electrode, from 0 to >100% consumption, at each frequency tested. Electrode pressure output was studied for each frequency. RESULTS: A greater number of shocks was required to fragment the plaster balls at higher frequencies (regression coefficient 1.93; p < 0.003). An inverse relation was found between the number of shocks necessary to break the stones and electrode consumption (regression coefficient -2.16; p < 0.001). The analysis of delivered pressure from the electrode failed to demonstrate a linear relation with frequency (regression coefficient -0.40; p < 0.728) or consumption (regression coefficient -1.11; p < 0.158). CONCLUSIONS: The number of shocks required to fragment a stone is influenced in part by the frequency at which the shockwaves are delivered. Increasing the shockwave frequency from 60 to 117 per minute in this study caused a significant rise in the number of shocks required to break the stone. The pressure output of the electrode was similar at the frequencies tested, thus making the difference in stone fragmentation secondary to the mechanism of stone disintegration and not the function of the electrode.

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OBJECTIVES: To determine whether mechanical percussion combined with inversion (MPI) therapy and forced diuresis can move stone fragments out of the lower pole of the kidney. METHODS: Twelve patients with lower pole residual stone fragments at least 2 weeks after shock wave lithotripsy were treated using the following protocol. Eleven patients received 20 mg of furosemide before MPI therapy. Patients were treated in the prone Trendelenberg position on a pivoting stretcher and given 10 minutes of percussion over the flank using a mechanical chest physiotherapy percussor. Stone location was documented with plain abdominal radiographs before, immediately after, and 2 weeks following MPI therapy. Voided urine was strained immediately after MPI therapy and throughout the study period. RESULTS: Abdominal radiographs before and after treatment demonstrated movement of fragments out of the lower pole in 11 patients. In 8 patients, the lower pole appeared entirely clear of fragments on the immediate post-treatment film. Four patients passed stone fragments in their first voided urine. Ten patients passed stone fragments during the 2-week follow-up period. CONCLUSIONS: MPI therapy combined with diuresis can effectively mobilize stone fragments out of the lower pole calyces and appears to aid in the passage of fragments.

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OBJECTIVE: To compare the outcome, advantages and disadvantages of retropubic and perineal approach to radical prostatectomy, as performed by one surgeon. PATIENTS AND METHODS: This unrandomized study included 138 patients who underwent either radical retropubic (RRP) or radical perineal prostatectomy (RPP), based on the specific conditions or the patient's choice; 79 patients (mean age 64.6 years) underwent RPP and 59 (mean age 61.7 years) RRP. Outcome measures included estimated blood loss, the incidence of blood transfusions, positive margins and complications, operative duration, analgesic use, days in hospital and quality of life. RESULTS: There was no difference in operative duration, and the incidence of positive margins or complications between the groups. The mean estimated blood loss in the RPP and RRP groups was 415 and 1,138 mL, respectively. The RPP group stayed a mean of 2.2 days less in hospital and took 2.8 days less to regain a full diet than the RRP group; the RPP group needed 1.7 days before using oral analgesics and the RRP group 3.8 days. Of patients in both groups, 85% were pad-free at one year and their overall quality of life was similar. CONCLUSIONS: The results of RRP and RPP are comparable; the advantages of the perineal approach include minimal blood loss, low-intensity postoperative nursing care, low analgesic use and earlier discharge from hospital.

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Infertile women without any inherent female infertility factors and able to secrete normal cervical mucus were studied prospectively in relation to post-coital sperm-mucus penetration (PCT) and their partner's seminal analysis, excluding men with azoospermia. Time-specific cumulative conception rates calculated as for life-table analysis were related to each measured seminal variable on routine analysis of 2-3 samples (volume, density, proportion with progressive motility, and proportion with normal morphology); to various derivatives from combinations of these variables; to seminal findings after vital staining; and to the PCT results. The best seminal predictor of fertility was the motile normal sperm density (MNSD), the 18 month conception rates being 57.4% +/- 4.6 (SE) and 30.2% +/- 5.9 (ratio 1.9, P less than 0.001) above and below a derived threshold value of 4 x 10(6)/ml. The PCT led to rates of 55.6% +/- 4.3 and 14.9% +/- 5.1 (ratio 3.73, P less than 0.001) for positive and negative results, respectively. The PCT also gave rise to a significantly distinct intermediate poor-positive sub-group (conception rate 30.6% +/- 9.0). Seminal analysis (the MNSD) did not affect the conception rate associated with a positive PCT but helped to discriminate further with a negative PCT (conception rates 22.5% +/- 8.7 with an MNSD above 4 x 10(6)/ml versus 5.6% +/- 4.8 below, P less than 0.05). The PCT was the single best predictor of fertility but seminal analysis (the MNSD) was of additional value after a negative PCT.

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