The pathogenesis and epidemiology of infection stones are well understood. While percutaneous lithotripsy and extracorporeal shock wave lithotripsy have emerged as the mainstay of extirpative therapy, surgical lithotomy is the standard to which other therapies must be compared. Adjunctive therapy with pharmacological agents that inhibit urease with few side effects and effective urinary acidifiers favor chemolysis. Diet and chemotherapy offer the hope of slowing stone growth and/or recurrence in patients with chronic urease-producing bacteriuria.

Neuropathic bladder dysfunction commonly results in urinary retention, incontinence, or both. At present, catheterization is commonly used in these patients to empty the bladder, but bacteriuria is a common result. Construction of a device that combines infection-resistant materials and a closed ecosystem has been attempted, yielding a prototype tissue-bonding cystostomy device. This device and the results of the early trials are described.

Ureteral replacement has always been a challenge. Two approaches have been explored: in situ augmentation or replacement and extra-anatomic passage of a conduit. An in-situ prosthetic ureter is basically a simple alloplastic tube connected to the urinary tract by end-to-end sutures or by intubation and closure. Antireflux devices and peristaltic mechanisms are not necessary. Among the in-situ designs, only those composed of silicone and silicone rubber have performed at all well. Tissue engineering and acellular matrix grafts have produced impressive early results. Subcutaneous ureteral replacement with alloplasts, including a coaxial assembly of an inner silicone and outer expanded polytetrafluoroethylene tube, has produced good results. In the future, we are likely to see bioengineered neotissue combined with highly porous and infection-resistant alloplasts to create better and more functional neo-organs.

An artificial bladder should provide adequate urine storage, allow volitional complete evacuation of urine and preserve renal function, Moreover, its structure has to be biocompatible, resistant to urinary encrustation and tolerant to bacterial infection. Various solutions have been proposed over the years to achieve these multiple requirements. However, most of these solutions and their corresponding prototypes did not advance beyond the stage of a preliminary report of experimental data. This review will bring out the 'proof of principal' in alloplastic prosthetic bladder, including type of alloplast and design concept and the recent development in tissue engineering approachs.

Fournier's gangrene is an uncommon but potentially lethal disease caused by a mixed infection of gram negative and anaerobic bacteria. There are many associated factors that put a man at risk, and an identifiable source can be found in 95% of patients. First symptoms are malaise, fever, and scrotal discomfort, but toxic symptoms can rapidly occur and be differentiated by the original site of infection. Early detection, extensive surgical debridement, intravenous antibiotics, and hemodynamic resuscitation are crucial to survival.

Sutured visceral anastomoses are time-consuming and complex when performed endoscopically. Theoretically, laser-welded visceral anastomoses are possible and are potentially easier and quicker to perform endoscopically than the sutured anastomoses. In this living canine study, we compared the operating time and intraluminal bursting pressure of laser-welded vs sutured anastomoses of (1) common bile duct (CBD), (2) small intestine, (3) colon and (4) ureter. Each organ was joined to itself using both anastomotic techniques. Welded anastomoses were much quicker in each organ system. Watertight anastomoses were achieved in each organ tested with both anastomotic techniques. intraluminal hydrostatic bursting pressures occurred at lower pressures (approximately 70% of sutured anastomosis bursting pressure) in all organs. Though not qualified, tensile disruption pressure appeared to be significantly lower in the welded anastomoses as compared to the sutured anastomoses. Laser-welded visceral anastomoses are rapid and watertight. Compared to sutured anastomoses, welded anastomoses are less secure to intraluminal bursting pressures and probably less to tensile pressures. Strength enhancing adjunctive measures, such as serosal adhesives or serosal clips, may strengthen welded anastomoses and are worthy of additional studies.

Bladder reconstruction may be required in a variety of pathological conditions, including bladder cancer, irradiation cystitis, interstitial cystitis, tuberculosis, and various congenital anomalies. Currently, bladder reconstruction is done with an autogenous bowel segment. Use of a total prosthetic bladder as an intracorporeal urinary reservoir has been an elusive goal for many decades. Many investigational and a few clinical trials have been performed in an attempt to develop a near-nornal bladder prosthesis utilizing alloplastic materials. To date the ideal prosthetic bladder has not been developed. However, cumulative experimental studies suggest that many, perhaps all, of the ideal functional characteristics of a total prosthetic bladder are possible. Basically, two different alloplastic models have been investigated.

Six patients with long-standing interstitial cystitis (IC) were treated with intravesical electromotive drug-assisted (EMDA) therapy using lidocaine (1.5%) and 1:100,000 epinephrine in aqueous solution. A stainless-steel silver-coated anode placed through an 18F Foley catheter was positioned in the urinary bladder, and a 5 x 10-cm dispersion electrode (cathode) was placed on the suprapubic skin, which was well lubricated with conductive jelly. The two electrodes were connected to a pulsed DC generator, and electrical current was slowly ramped from 0 to 15 mA while the lidocaine and epinephrine were in the urinary bladder. After 40 minutes of current application, the bladder was hydraulically dilated to maximum tolerance. Significant bladder dilatation was achieved without systemic symptoms. Post-treatment, voiding symptoms decreased, as did suprapubic and perineal pain, and in four patients, the results have been durable.

Tissue welding with laser energy is a new technique for reconstructive surgery. The potential advantages of laser welding are (a) lack of foreign body reaction, (b) decreased operative time, (c) less tissue manipulation, and (d) effective union of tissues equivalent to sutured anastomoses. We have performed ureteral anastomoses in adult mongrel dogs using a KTP 532 nm laser at an intensity of 1.4 W. Multiple "spot welds" of 1-s duration were utilized in a single layer anastomosis. Laser-welded anastomoses were performed with and without protein solder (33% and 50% human albumin) and were compared to sutured anastomoses. The laser-welded anastomoses required less operative time and provided bursting pressure levels similar to those of traditional sutured anastomoses. There was no advantage or disadvantage to the addition of human albumin as a solder in these experimental studies.

PURPOSE:Electromotive drug delivery (EMDA) is the use of an electrical field to enhance penetration of ionized drugs into local tissues. Intraurinary EMDA may be of value in the treatment of various pathological conditions involving the urinary bladder, prostate gland and urethra. We have developed an animal model to study this hypothesis.MATERIALS AND METHODS:Anesthetized adult mongrel dogs were studied. An intravesical anode was inserted through a Foley catheter into the urinary bladder. Two patch electrodes were positioned on the animals' abdominal skin. Both skin and intravesical electrodes were attached to a direct current generator. The bladder was then distended with an anionic blue dye (methylene blue). Fifteen milliamperes (15 mA) pulsed direct current was applied for 40 minutes. After EMDA, the bladder was surgically removed and representative sections of full thickness bladder wall were immediately frozen in liquid nitrogen. Methylene blue was used to visually demonstrate EMDA-enhanced anion penetration into bladder submucosa and muscularis.RESULT:This experimental model demonstrates significant submucosal and muscularis methylene blue penetration in the presence of the electric field.CONCLUSION:Electromotive drug delivery technology may have applications for treating bladder pathology.

OBJECTIVE:To examine the usefulness of clinical stage, tumour differentiation and prostate-specific antigen (PSA) level, alone and in combination, to predict regional nodal metastases in individual patients with localized prostate cancer.PATIENTS AND METHODS:The usefulness of digital rectal examination (DRE), biopsy Gleason sum and PSA, alone and in combination, to predict nodal metastases in an individual patient was examined. The study included 689 patients who had laparoscopic or open pelvic lymph node dissection for clinical stage T1-3 prostate cancer. The Kruskal-Wallis test, Mantel-Haenszel test, chi-squared test and logistic regression were used for continuous, ordinal, categorical, and multivariate analysis, respectively.RESULTS:Of the 689 patients who underwent radical prostatectomy, 52 (8%) had nodal metastases. Although clinical stage, DRE, pre-operative PSA level and biopsy Gleason sum were significantly related in the univariate analysis, only pre-operative PSA level and biopsy Gleason sum were significant predictors of lymph node status in a multivariate analysis. However, based on a receiver operating characteristic curve, a model with satisfactory sensitivity and specificity could not be obtained.CONCLUSION:Current estimations of primary prostate cancer biology using pre-operative PSA level, clinical stage and biopsy Gleason sum are not sufficiently sensitive to predict nodal metastases, and pelvic lymphadenectomy remains the definitive method of detection.

Establishment of a nephrostomy tract is a prerequisite for many endourologic procedures of the upper urinary tract, We reviewed our initial experience with 31 retrograde nephrostomies to determine the advantages and disadvantages and the learning curve for the procedure, All but one of the attempts were successful, and no complications were attributable to the nephrostomy puncture, The procedure time averaged 21.1 minutes in nondilated collecting systems but 32.0 minutes in hydronephrotic kidneys (P < 0.01), The mean procedure time in our first 10 successful cases was 36.2 minutes, but it decreased to 22.6 minutes in the second 10 successful cases (P < 0.02), Radiation exposure was also minimized early, with a mean fluoroscopy time of 3.5 minutes in our first 10 successful cases and 1.5 minutes in our second 10 successful cases (P < 0.02), Similarly, both procedure and fluoroscopy times decreased further in the most recent 10 successful cases, Retrograde nephrostomy is a safe procedure, is easier in a nondilated collecting system, and can be mastered with a short learning curve with minimal radiation exposure.

PURPOSE:To determine the effect of iontophoresis (electrical current for therapeutic purposes) on the growth of pathogenic bacteria in human urine. MATERIALS AND METHODS:Pathogenic bacteria were isolated and inoculated into a dynamic in vitro artificial bladder model. Pooled sterile human urine was regulated through the artificial bladder by intravenous tubing and pumps to simulate filling and emptying of the human bladder. The effect of electrical current on bacterial growth in the system was then studied. RESULTS:When iontophoresis is applied at low bacterial concentrations ( < 10(8) colony forming units [CFU]/l.), inhibition of bacterial growth occurs. However, when iontophoresis is applied after fulminant growth of bacteria ( > 10(8) CFU/l.), no inhibition of bacterial growth occurs. Iontophoresis was not found to enhance the antibacterial action of gentamicin to resistant Pseudomonas aeruginosa. CONCLUSIONS:Iontophoresis inhibits bacterial growth at low bacterial concentrations. It does not inhibit bacterial growth after infectious levels have been attained, and it does not potentiate the action of gentamicin on resistant Pseudomonas aeruginosa.

British Journal of UrologyVolume 74, Issue 5 p. 674-675 Retroperitoneal endoscopic excision of renal cysts H. Y. WONG, H. Y. WONG *Scott Department of Urology, Baylor College of Medicine, Houston, Texas, USA H.Y. Wong, MD, FRCSC, Fellow.Search for more papers by this authorD. P. GRIFFITH, Corresponding Author D. P. GRIFFITH *Scott Department of Urology, Baylor College of Medicine, Houston, Texas, USA D.P. Griffith, MD, Professor.+Scott Department of Urology, Baylor College of Medicine, 6560 Fannin. Suite 1004, Houston, Texas 77030, USA.Search for more papers by this author H. Y. WONG, H. Y. WONG *Scott Department of Urology, Baylor College of Medicine, Houston, Texas, USA H.Y. Wong, MD, FRCSC, Fellow.Search for more papers by this authorD. P. GRIFFITH, Corresponding Author D. P. GRIFFITH *Scott Department of Urology, Baylor College of Medicine, Houston, Texas, USA D.P. Griffith, MD, Professor.+Scott Department of Urology, Baylor College of Medicine, 6560 Fannin. Suite 1004, Houston, Texas 77030, USA.Search for more papers by this author First published: November 1994 https://doi.org/10.1111/j.1464-410X.1994.tb09208.x AboutPDF 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 No abstract is available for this article. Volume74, Issue5November 1994Pages 674-675 RelatedInformation

We describe a conceptual model for drainage of the dysfunctional bladder. Experimental data from investigations involving several species of animals are presented to support the hypothesis that mature tissue-bonded alloplastic tubes drain urine effectively and are tolerant and resistant to endogenous and exogenous bacteria. We conclude that preliminary clinical trials of a tissue-bonded cystostomy are warranted. We postulate that success in these trials may offer a new alternative for the management of severe vesical dysfunction.

Endoscopic lymphadenectomy of the iliac and obturator nodes is feasible, and the morbidity to date has been acceptable. Further studies are needed to evaluate the procedure's efficacy and to delineate the clinical situations wherein it is most useful. The technique demands a significant training commitment from surgeons and may become obsolete with the evolution of more sophisticated approaches.

The complexity of a total alloplastic prosthetic bladder is evident when one considers the fact that total alloplastic hearts have been applied clinically, although to a limited extent, for several years, whereas prosthetic bladders are still at the investigational stage in animals.1 The ideal alloplastic bladder should be easy to implant surgically; preserve renal function; provide adequate urinary storage; allow volitional, complete evacuation of urine; be biocompatible; be resistant to extraluminal infection; be tolerant of intraluminal infection; deter intraluminal infection; discharge urine per urethram, and be mechanically reliable.2 We review the experimental and clinical experience using alloplastic biomaterials for partial and total bladder replacement.