Intermediate term outcomes associated with the surveillance of ureteropelvic junction obstruction in adults.

PURPOSE: We determined the outcome of minimally symptomatic adult ureteropelvic junction obstruction in a group of patients treated conservatively with an active surveillance regimen. MATERIALS AND METHODS: A total of 27 patients with asymptomatic or minimally symptomatic ureteropelvic junction obstruction were treated conservatively. All patients were evaluated with diuretic renograms. Ureteropelvic junction obstruction was defined by an obstructive pattern of the clearance curve and/or T1/2 greater than 20 minutes. Followup consisted of an office visit and renogram every 6 to 12 months. Cases of greater than 10% loss of relative renal function of the affected kidney, development of pyelonephritis and/or more than 1 episode of acute pain were considered active surveillance failures, and treatment was recommended. RESULTS: Of the 27 patients 6 were lost to followup, leaving 21 (median age 47 years) with sufficient followup for analysis. In the 4 patients (19%) who initially presented with mild pain that led to the diagnosis of ureteropelvic junction obstruction, the pain completely resolved. Ipsilateral relative renal function decreased significantly in 2 patients (9.5%, mean reduction 14%). Pain worsened in 3 patients (14.3%) and de novo pain occurred in 1 (4.7%). Surgical intervention for ureteropelvic junction obstruction was required in 6 patients (29%) at an average of 34 months. In total 15 patients (71%) remained on surveillance with a mean followup of 48 months. CONCLUSIONS: Active surveillance seems to be a reasonable initial option for asymptomatic or mildly symptomatic adult patients with ureteropelvic junction obstruction because only approximately 30% have progression to surgical intervention within 4 years of diagnosis. This strategy offers the advantage of individualizing therapy according to symptoms and renographic findings.

Lower pole I: a prospective randomized trial of extracorporeal shock wave lithotripsy and percutaneous nephrostolithotomy for lower pole nephrolithiasis-initial results.

PURPOSE: The efficacy of shock wave lithotripsy and percutaneous stone removal for the treatment of symptomatic lower pole renal calculi was determined. MATERIALS AND METHODS: A prospective randomized, 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 randomized to percutaneous stone removal (58 treated, 2 awaiting treatment) and 68 with a mean stone size of 14.03 mm. were randomized 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.

The impact of intense laparoscopic skills training on the operative performance of urology residents.

PURPOSE: As laparoscopy has become more commonplace in urology, increased emphasis has been placed on laparoscopic education. We assessed the impact of laparoscopic skills training on the operative performance of urological surgeons inexperienced with laparoscopy. MATERIALS AND METHODS: Urology residents were prospectively randomized to undergo laparoscopic skills training (6) or no training (6). Baseline assessment of operative performance (scale 0 to 35) during porcine laparoscopic nephrectomy was completed by all subjects. Cumulative time to complete laparoscopic tasks using an inanimate trainer was also recorded. The skills training group then practiced inanimate trainer tasks for 30 minutes daily for 10 days. The 2 groups then repeated the timed inanimate trainer tasks and underwent repeat assessment of the ability to perform porcine laparoscopic nephrectomy. RESULTS: At baseline no statistical difference was noted in laparoscopic experience, inanimate trainer time or overall operative assessment in the 2 groups. In the skills training group mean cumulative time to complete inanimate trainer tasks decreased from 341 to 176 seconds (p = 0.003), while in the control group it decreased from 365 to 301 (p = 0.15). Operative assessment improved from initial to repeat porcine laparoscopic nephrectomy regardless of the trained versus control randomization grouping (22.0 to 27.8, p = 0.0008 and 20.8 to 26.5, p = 0.00007, respectively). CONCLUSIONS: In vivo experience enables urological surgeons inexperienced with laparoscopy to improve significantly in all aspects of complex laparoscopic procedures. In this pilot study the magnitude of improvement was independent of additional training in laparoscopic skills. Educational curriculum should include in vivo practice in addition to skills training.

Prospective randomized trial comparing shock wave lithotripsy and ureteroscopy for management of distal ureteral calculi.

PURPOSE: We compared the efficacy of shock wave lithotripsy and ureteroscopy for treatment of distal ureteral calculi. MATERIALS AND METHODS: A total of 64 patients with solitary, radiopaque distal ureteral calculi 15 mm. or less in largest diameter were randomized 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.

Laparoscopic radiofrequency thermal ablation of renal tissue with and without hilar occlusion.

PURPOSE: Few studies have evaluated the effect of radiofrequency thermal ablation on renal tissue, although it has been used clinically to treat small renal masses. We studied the size and histology of lesions created with radiofrequency thermal ablation administered via the laparoscopic approach with and without hilar occlusion in a porcine model. MATERIALS AND METHODS: The lower pole of each kidney was exposed laparoscopically in 11 farm pigs. In each kidney a 7-electrode dry radiofrequency thermal ablation probe was inserted at an identical location and deployed to a diameter of 2 cm. Energy was applied for 8 minutes at an average temperature of 100C. The left renal hilum of each pig was clamped during radiofrequency thermal ablation. Two pigs were sacrificed immediately, and 3 each were sacrificed at 24 hours, 2 and 4 weeks. The size and shape of the lesions created were measured and examined histologically. RESULTS: There were no intraoperative or postoperative complications. Laparoscopic ultrasound confirmed probe placement but did not monitor lesion progression. Acutely lesions were firm and white with a small adjacent hemorrhagic zone. Histological evaluation revealed preserved renal architecture but the loss of distinct cytoplasmic features. Nicotinamide adenine dinucleotide staining demonstrated no viable cells within the lesions. In surviving animals pelvicaliceal integrity was preserved. In the 2 and 4-week survival groups kidneys treated with hilar occlusion had larger lesions than nonoccluded kidneys but the differences were not significant at 4 weeks (3.2 x 2.7 x 2.5 cm. and 3.5 x 1.7 x 2.0, respectively, p >0.05). Histologically untreated parenchyma of hilar occluded kidneys demonstrated changes consistent with chronic pyelonephritis. In 1 kidney radiofrequency thermal ablation with hilar occlusion resulted in complete lower pole loss at 4 weeks. CONCLUSIONS: In the porcine model renal radiofrequency thermal ablation creates rapid and completely devitalized lesions of consistent size and shape. Hilar occlusion may result in slightly larger lesions but risks damage to the whole renal unit.

How do urology residents manage personal finances?

OBJECTIVES: To examine personal financial management among residents to answer three research questions: do residents make reasonable financial choices; why do some residents not save; and what steps can be taken to improve residents' personal financial decisions. METHODS: Portions of the Federal Reserve Board's Survey of Consumer Finances were modified and piloted to elicit demographic, expense, saving, and income data. The final questionnaire was completed by 151 urology residents at 20 programs. RESULTS: Comparing residents with the general population in the same age and income categories, the median debt/household income ratio was 2.38 versus 0.64. Residents had greater educational debt, greater noneducational debt, and lower savings. Resident participation in retirement accounts was 100% at institutions with employer-matching 401k or 403b plans, 63% at institutions with nonmatching 401k or 403b plans, and 48% at institutions without retirement plans for residents (P = 0.002). Fifty-nine percent of residents budgeted expenses, 27% had cash balances below $1000, 51% had paid interest charges on credit cards within the previous year, and 12% maintained unpaid credit card balances greater than $10,000. The median resident income was $38,400. CONCLUSIONS: A significant minority of residents appear not to make reasonable financial choices. Some residents save little because of a failure to budget, indebtedness, high projected income growth, or insufficient attention to personal financial management. Residents save more when they are eligible for tax-deferred retirement plans, particularly when their institution matches their contributions. Many residents would benefit from instruction concerning prudent financial management.

Renal parenchymal injury after standard and mini percutaneous nephrostolithotomy.

PURPOSE: Mini percutaneous nephrostolithotomy was developed for use in children and in adults with a reduced renal reserve to minimize the morbidity and renal parenchymal damage presumed to occur with traditional percutaneous nephrostolithotomy. We compared the extent of renal injury incurred by different sized nephrostomy tracts in female farm pigs undergoing 11 or 30Fr percutaneous nephrostomy. MATERIALS AND METHODS: Bilateral percutaneous nephrostomy was attempted via a mid or lower pole calix under fluoroscopic guidance in 6 pigs. In 2 pigs the procedure was unsuccessful on 1 side, leaving 5 successfully established nephrostomy tracts on each side. In each pig the right percutaneous tract was dilated with a 28Fr dilating balloon and a 30Fr Amplatz working sheath (Cook Urological, Spencer, Indiana) was positioned in the collecting system. On the left side an 11Fr sheath (Cook Urological) was placed. The sheaths were removed after 1 hour and nephrostomy tubes (22Fr on the right and 8Fr on the left side) were left in place overnight and then removed. Six weeks later the pigs were sacrificed and the kidneys were harvested. The nephrostomy tracts were identified grossly and examined microscopically, and the fibrotic scar was measured using digital analysis. The volume of scar was estimated using the calculated volume of a cylinder. RESULTS: At kidney harvest all 10 kidneys appeared grossly normal. No intra-abdominal urine collection or perirenal hematoma was noted. Mean estimated scar volume of the 30 and 11Fr tracts was 0.29 and 0.40 cc, which translates into a mean fractional loss of parenchyma of 0.63% and 0.91%, respectively (p not significant). CONCLUSIONS: Renal parenchymal damage resulting from the creation of a nephrostomy tract is small compared to overall renal volume regardless of the size of the nephrostomy tract. Consequently there is no advantage to the use of a small access sheath based on renal scarring alone.

Hemostatic laparoscopic partial nephrectomy: cable-tie compression.

OBJECTIVES: Laparoscopic partial nephrectomy (LPN) has generally been reserved for small exophytic lesions because of the limited hemostatic capabilities when excising large segments of renal parenchyma. To overcome this problem, we investigated a technique of laparoscopic reversible, regional hypoperfusion using a cable-tie to minimize blood loss and optimize exposure. METHODS: Ten domestic pigs underwent LPN after securing a cable-tie around one pole of the kidney and tightening it until the distal parenchymal surface blanched completely. Eight large amputations involving the collecting system and eight smaller amputations excluding the collecting system were performed using laparoscopic scissors. Fibrin glue was applied to seal the cut surface prior to cable-tie removal. Four pigs (4 large and 4 small amputations) were killed immediately and methylene blue was injected retrograde into the ureter to identify collecting system leaks. The remaining 6 pigs (4 large and 4 small amputations) were killed 4 weeks later and retrograde urograms were performed to assess collecting system integrity. RESULTS: Median cable-tie ischemia time was 15 minutes (range 7 to 48) and median blood loss was 30 mL (range 10 to 300). In each case, hemostasis was attained with fibrin glue. In the survival group, all 4 small amputations healed with a fibrotic scar. In the large amputation group, 1 animal died from urinary extravasation on postoperative day 4. The collecting systems of the remaining 3 pigs sealed completely. CONCLUSIONS: In the porcine model, cable-tie-assisted LPN provides an almost bloodless surgical field that facilitates rapid resection of large renal segments and hemostasis during a short ischemic period. We anticipate that this technique will broaden the clinical application of LPN.

Prevention of nephrolithiasis.

The high incidence of recurrence after an initial stone event underscores the need for an effective medical prophylactic program. Dietary modification and drug therapies have long been advocated to reduce the likelihood of stone recurrence. While the efficacy of a high fluid intake has been validated in a randomized trial, the benefit of other dietary measures is based on modulation of urinary stone risk factors and outcomes derived from observational studies. Several drug therapies have been evaluated in a limited number of prospective, randomized trials and efficacy has been demonstrated for thiazides, allopurinol and alkali citrate in some populations of recurrent stone formers. The role of selective versus nonselective therapy for stone prevention awaits further study.

Renal cystic disease. Laparoscopic management.

Laparoscopy offers a safe and efficacious means of ablating symptomatic simple renal cysts while conferring the usual benefits of shorter hospital stay, quicker convalescence, and reduced postoperative pain, although no direct comparison with open surgery has been performed. For indeterminate, complex renal cysts, laparoscopic exploration may spare the patient a morbid open operation to assess a cystic lesion of indeterminant risk. Although laparoscopic removal of kidneys with ADPKD remains a technically challenging exercise, centers of laparoscopic expertise have demonstrated the safety and feasibility of the procedure, thereby expanding the benefits of laparoscopic surgery to patients traditionally relegated to open surgical management.

In vitro comparison of shock wave lithotripsy machines.

PURPOSE: We tested the hypothesis that shock wave lithotripsy machines vary in the ability to fragment stones to small size. MATERIALS AND METHODS: Calcium oxalate monohydrate, calcium hydrogen phosphate dihydrate, cystine and magnesium ammonium phosphate hexahydrate calculi were fragmented in vitro with the 22 kV. Dornier HM3, section sign 20 kV. Storz Modulith SLX, parallel, 15.6 kV. Siemens Lithostar C, paragraph sign 24 kV. Medstone STS-T,** 26 kV. HealthTronics LithoTron 160,daggerdagger 20 kV. Dornier Doli section sign and 22.5 kV. Medispec Econolithdouble daggerdouble dagger lithotriptors. Stones were given 500 or 2,000 shocks, or the Food and Drug Administration limit. Post-lithotripsy fragment size was characterized using sequential sieves and compared. RESULTS: Stone mass was statistically similar in the cohorts (p >0.94). Fragment size decreased as the number of shocks increased when the machine and stone composition were constant. Magnesium ammonium phosphate hexahydrate calculi were completely fragmented by all devices. At Food and Drug Administration treatment limits the mean incidence per device of calcium hydrogen phosphate dihydrate, calcium oxalate monohydrate, cystine and magnesium ammonium phosphate hexahydrate stones rendered into fragments greater than 2 mm. was 0% for the HM3, Modulith SLX and Lithostar C, 10% for the STS-T, 3% for the LithoTron 160, 29% for the Doli and 18% for the Econolith (p = 0. 04); 0% for the HM3, Modulith SLX, Lithostar C, STS-T and LithoTron 160, 4% for the Doli and 9% for the Econolith (p = 0.15); 1% for the HM3, 0% for the Modulith SLX, 1% for the Lithostar C, 10% for the STS-T, 14% for the LithoTron 160, 3% for the Doli and 9% for the Econolith (p = 0.44); and 1% for the HM3, 0% for the Modulith SLX, 1% for the Lithostar C, 10% for the STS-T, 14% for the LithoTron 160, 3% for the Doli and 9% for the Econolith (p = 0.44), respectively. CONCLUSIONS: Shock wave lithotriptors vary in fragmentation ability. The HM3, Modulith SLX and Lithostar C machines yield smaller fragments than other machines.

Laser lithotripsy and cyanide.

BACKGROUND AND PURPOSE: Holmium:YAG lithotripsy of uric acid calculi produces cyanide. The laser and stone parameters required to produce cyanide are poorly defined. In this study, we tested the hypotheses that cyanide production: (1) varies with holmium:YAG power settings; (2) varies among holmium:YAG, pulsed-dye, and alexandrite lasers; and (3) occurs during holmium:YAG lithotripsy of all purine calculi. MATERIALS AND METHODS: Holmium:YAG lithotripsy of uric acid calculi was done using various optical fiber diameters (272-940 microm) and pulse energies (0.5-1.5 J) for constant irradiation (0.25 kJ). Fragmentation and cyanide were quantified. Cyanide values were divided by fragmentation values, and fragment sizes were characterized. To test the second hypothesis, uric acid calculi were irradiated with Ho:YAG, pulsed-dye, and alexandrite lasers. Fragmentation and cyanide were measured, and cyanide per fragmentation was calculated. Fragment sizes were characterized. Finally, Ho:YAG lithotripsy (0.25 kJ) of purine and nonpurine calculi was done, and cyanide production was measured. RESULTS: Fragmentation increased as pulse energy increased for the 550- and 940-microm optical fibers (P < 0.05). Cyanide increased as pulse energy increased for all optical fibers (P < 0.002). Cyanide per fragmentation increased as pulse energy increased for the 272-microm optical fiber (P = 0.03). Fragment size increased as pulse energy increased for the 272-microm, 550-microm, and 940-microm optical fibers (P < 0.001). The mean cyanide production from 0.25 kJ of optical energy was Ho:YAG laser 106 microg, pulsed-dye 55 microm, and alexandrite 1 microg (P < 0.001). The mean cyanide normalized for fragmentation (microg/mg) was 1.18, 0.85, and 0.02, respectively (P < 0.001). The mean fragment size was 0.6, 1.1, and 1.9 mm, respectively (P < 0.001). After 0.25 kJ, the mean amount of cyanide produced was monosodium urate stones 85 microg, uric acid 78 microg, xanthine 17 microg, ammonium acid urate 16 microg, calcium phosphate 8 microg, cystine 7 microg, and struvite 4 microg (P < 0.001). CONCLUSIONS: Cyanide production varies with Ho:YAG pulse energy. To minimize cyanide and fragment size, Ho:YAG lasertripsy is best done at a pulse energy < or = 1.0 J. Cyanide production from laser lithotripsy of uric acid calculi varies among Ho:YAG, pulsed-dye, and alexandrite lasers and is related to pulse duration. Cyanide is produced by Ho:YAG lasertripsy of all purine calculi.

Laparoscopic nephrectomy for benign disease.

Nearly 10 years of experience with laparoscopic nephrectomy for benign renal disease has shown that the procedure can be performed safely with a complication rate comparable with open surgery. Improvements in the skill, instrumentation, and technique of the laparoscopist have expanded the indications for the procedure to include larger (polycystic kidneys) and in some cases more complex (xanthogranulomotous pyelonephritis) specimens. Continued demonstration of reduced postoperative pain, shorter hospital stay, and more rapid recovery along with decreasing operative times have made laparoscopy the preferred approach for the surgical removal of benign kidneys.

Meta-analysis of randomized trials for medical prevention of calcium oxalate nephrolithiasis.

OBJECTIVES: To determine the efficacy of commonly used medications in comparison with placebo or no treatment for the prevention of renal stone recurrence (metaphylaxis) as documented in the literature. METHODS: A MEDLINE search identified 14 randomized, controlled trials comprising 20 treatment arms and 6 different drug therapies for the prevention of stone recurrence. The active treatment arms from each of the trials were combined, and the results were compared with those of the control or no treatment arms overall and for each category of drug therapy (thiazide diuretics, allopurinol, phosphate, magnesium, and alkali citrate). A meta-analysis was performed of the combined treatment and control arms for all trials from which sufficient data were provided, both for overall medical therapy and for thiazide treatment. RESULTS: A statistically significant benefit of drug therapy for stone metaphylaxis was identified (P = 0.04), largely because of the benefit of thiazides compared with placebo or no treatment (P = 0.02). Allopurinol conferred no overall benefit, although the only trial evaluating therapy in hyperuricosuric patients showed a statistically significant benefit. CONCLUSION: Medical therapy for calcium stone disease reduces the incidence of recurrence. Although only thiazide diuretics among the drug therapies were shown to significantly reduce stone recurrence, variability in study design and study population precluded adequate analysis of other drug therapies such as alkali citrate. Standardization of study design and reporting should improve the evaluation of the efficacy of new drug treatments.

Sensitivity of noncontrast helical computerized tomography and plain film radiography compared to flexible nephroscopy for detecting residual fragments after percutaneous nephrostolithotomy.

PURPOSE: We prospectively compared plain film radiography and noncontrast, thin cut helical computerized tomography (CT) to flexible nephroscopy for detecting residual stones after percutaneous nephrostolithotomy. MATERIALS AND METHODS: We prospectively evaluated 36 patients (41 renal units) undergoing percutaneous nephrostolithotomy for large (greater than 3 cm., 23 renal units) or staghorn (18 renal units) calculi. All patients underwent postoperative imaging with plain film of the kidneys, ureters and bladder and noncontrast helical CT, and flexible nephroscopy on postoperative day 2 or 3. The size and location of residual fragments determined radiographically and identified by flexible nephroscopy were compared. RESULTS: Plain film radiography and CT detected an average of 0.7 and 3.4 stones per renal unit, respectively. With a mean operating time plus or minus standard deviation of 77.3+/-35 minutes and a mean fluoroscopy time of 7.6+/-6.7 minutes, an average of 2.3 stones per renal unit were retrieved at flexible nephroscopy. In 90.2% of renal units all calices could be directly inspected. The sensitivity and specificity were 46% and 82% for plain film radiography, and 100% and 62% for CT, respectively, using flexible nephroscopy as the gold standard for detecting residual stones. The overall stone-free rate after flexible nephroscopy was 92.6%. The cost of this procedure is $5,625.13 compared to $220 for CT, including the interpretation fee, at our institution. CONCLUSIONS: Selective use of flexible nephroscopy after percutaneous nephrostolithotomy based on positive CT findings will avoid an unnecessary operation in 20% of patients. The rate of unnecessary procedures is 32% if all patients undergo flexible nephroscopy, regardless of radiographic findings. At our institution this strategy will result in a cost savings of $109,687 per 100 patients.

The usefulness of touch preparation cytological evaluation and prostatic capsule involvement in prediction of prostate cancer recurrence.

PURPOSE: Touch preparation cytology has been used in oncology as a technique to assist in predicting local tumor recurrence. We prospectively investigated the relationship between this cytological evaluation and the standard histological method of assessing specimens, measuring the distance from the tumor to the various anatomical boundaries and disease recurrence in radical retropubic prostatectomy patients. MATERIALS AND METHODS: In a prospective study of 91 consecutive clinical stages T1c and T2 cancer cases radical retropubic prostatectomy touch preparation cytology was performed intraoperatively in an anatomical fashion (apex, posterior, lateral right and left, and base). A single blinded cytopathologist reviewed all prostate touch preparation specimens and categorized them as malignant, benign or atypical cells. Benign or atypical cells were classified as negative cytology. Detailed histological margin analysis of the surgical specimens was also done in which distances between the tumor front, and prostate capsule (inner and outer edge) and surgical margins (apex, posterior, right and left lateral, and base) were measured. All specimens were re-staged by the same pathologist. Median followup was 38 months. Disease recurrence was determined biochemically (prostate specific antigen), and with bone scans, prostatic fossa biopsies and digital rectal examinations. RESULTS: Of the 91 specimens 25 were excluded from study because distance measurements could not be made for technical reasons. Multivariate analysis was performed on the remaining 66 patients based on the variables of stage, age, cytology status, distance from tumor to the inner prostatic capsule, distance from tumor to the surgical margin and postoperative Gleason sum. The only variable with independent prognostic value was postoperative Gleason sum (p = 0.04). Cytology status was not statistically significant (p = 0.07) nor were distance data to the inner capsule (p >0.05) and surgical margin (p >0.05). CONCLUSIONS: Although touch preparation cytology does not enhance prognostic information already provided by Gleason sum, it does correlate highly with postoperative Gleason sum. Other gross macroscopic variables, that is pathological stage, margin status and distance measurements, although lacking in independent predictive value, correlated with postoperative Gleason sum. The constancy of Gleason sum leads us to believe that the key to predicting prostatic cancer behavior lies not on the macroscopic but on the molecular or cellular level. Of the various factors analyzed in this study postoperative Gleason sum remains the most powerful predictor of recurrence risk.

Optimal method of urgent decompression of the collecting system for obstruction and infection due to ureteral calculi.

PURPOSE: We compare the efficacy of percutaneous nephrostomy with retrograde ureteral catheterization for renal drainage in cases of obstruction and infection associated with ureteral calculi. MATERIALS AND METHODS: We randomized 42 consecutive patients presenting with obstructing ureteral calculi and clinical signs of infection (temperature greater than 38 C and/or white blood count greater than 17,000/mm.3) to drainage with percutaneous nephrostomy or retrograde ureteral catheterization. Preoperative patient and stone characteristics, procedural parameters, clinical outcomes and costs were assessed for each group. RESULTS: Urine cultures obtained at drainage were positive in 62.9% of percutaneous nephrostomy and 19.1% of retrograde ureteral catheterization patients. There was no significant difference in the time to treatment between the 2 groups. Procedural and fluoroscopy times were significantly shorter in the retrograde ureteral catheterization (32.7 and 5.1 minutes, respectively) compared with the percutaneous nephrostomy (49.2 and 7.7 minutes, respectively) group. One treatment failure occurred in the percutaneous nephrostomy group, which was successfully salvaged with retrograde ureteral catheterization. Time to normal temperature was 2.3 days in the percutaneous nephrostomy and 2.6 in the retrograde ureteral catheterization group, and time to normal white blood count was 2 days in the percutaneous nephrostomy and 1.7 days in the retrograde ureteral catheterization group (p not significant). Length of stay was 4.5 days in the percutaneous nephrostomy group compared with 3.2 days in the retrograde ureteral catheterization group (p not significant). Cost analysis revealed that retrograde ureteral catheterization was twice as costly as percutaneous nephrostomy. CONCLUSIONS: Retrograde ureteral catheterization and percutaneous nephrostomy effectively relieve obstruction and infection due to ureteral calculi. Neither modality demonstrated superiority in promoting a more rapid recovery after drainage. Percutaneous nephrostomy is less costly than retrograde ureteral catheterization. The decision of which mode of drainage to use may be based on logistical factors, surgeon preference and stone characteristics.

Transient cavitation and acoustic emission produced by different laser lithotripters.

Transient cavitation and shockwave generation produced by pulsed-dye and holmium:YAG laser lithotripters were studied using high-speed photography and acoustic emission measurements. In addition, stone phantoms were used to compare the fragmentation efficiency of various laser and electrohydraulic lithotripters. The pulsed-dye laser, with a wavelength (504 nm) strongly absorbed by most stone materials but not by water, and a short pulse duration of approximately 1 microsec, induces plasma formation on the surface of the target calculi. Subsequently, the rapid expansion of the plasma forms a cavitation bubble, which expands spherically to a maximum size and then collapses violently, leading to strong shockwave generation and microjet impingement, which comprises the primary mechanism for stone fragmentation with short-pulse lasers. In contrast, the holmium laser, with a wavelength (2100 nm) most strongly absorbed by water as well as by all stone materials and a long pulse duration of 250 to 350 microsec, produces an elongated, pear-shaped cavitation bubble at the tip of the optical fiber that forms a vapor channel to conduct the ensuing laser energy to the target stone (Moss effect). The expansion and subsequent collapse of the elongated bubble is asymmetric, resulting in weak shockwave generation and microjet impingement. Thus, stone fragmentation in holmium laser lithotripsy is caused primarily by thermal ablation (drilling effect).