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Background: A urethral stricture is a scar of the urethral epithelium which can cause obstructive voiding dysfunction with consequential damage of the upper urinary tract. Almost 45% of all strictures are iatrogenic; they develop in 2-9% of patients after radical prostatectomy, but can also occur after prostate cancer radiotherapy. This study provides 5‑year data of a certified prostate cancer center (PKZ) in terms of urethral strictures., Materials and Methods: Between 01/2008 and 12/2012 a total of 519 men were irradiated for prostate cancer (LDR and HDR brachytherapy as well as external beam radiation). The entire cohort was followed-up prospectively according to a standardized protocol (by type of irradiation). Short segment urethral strictures were treated by urethrotomy, recurrent and long segment stenosis with buccal mucosa urethroplasty., Results: A total of 18 of 519 (3.4%) patients developed a urethral stricture post-therapeutically, which recurred in 66% of cases after the first operative treatment. The largest risk for developing a urethral stricture is attributed to the HDR brachytherapy (8.9%)., Conclusion: Urethral strictures after prostate cancer radiotherapy should be diagnosed and treated in time for long-term preservation of renal function. The rate of radiogenic urethral strictures (3.4%) is equivalent to those after radical prostatectomy. Due to a high rate of recurrences, urethrotomy has a limited importance after irradiation.

Graft urethroplasty using free transplants has become a standard procedure in the therapy of complicated urethral strictures. Various types of tissues can be used as graft material and different criteria are important for the suitability of tissues for urethroplasty. It was recognized early on that the prepuce was an easy to harvest tissue with low morbidity and excellent functional results. In this article the suitability of this tissue for functional results will be discussed within the context of the biology of free transplants and the available literature.

The most commonly used treatment modality for urethral strictures is the direct visual internal urethrotomy (DVUI) method according to Sachse. It is an effective short-term treatment, but the long-term success rate is low. A number of factors influence the outcome of DVUI including stricture location, spongiofibrosis and previous endoscopic stricture treatment. Multiple urethrotomy has a negative impact on the success rate of subsequent urethroplasty. A thorough preoperative diagnostic work-up including combined retrograde urethrogram/voiding cystourethrogram (RUG/VCUG) and urethrocystoscopy is, therefore, mandatory to allow for patient counselling regarding the risk of stricture recurrence and other treatment options. After a failed primary DVUI, subsequent urethrotomy cannot be expected to be curative.

The use of oral mucosa for urethral stricture repair has become the standard approach in reconstructive urethral surgery. Compared to other tissues oral mucosa shows several advantages, such as simple harvesting, good urine tolerance and low harvesting morbidity. For defects of the male bulbar urethra measuring 2 cm or longer, urethral reconstruction with oral mucosa is the procedure of choice. The oral mucosa graft can be used as an inlay or as an onlay graft. Most repairs can be completed in one stage but for complex strictures two stages are needed.

Balanitis xerotica obliterans (BXO) is a chronic and progressive dermatitis of unknown aetiology and incidence. Its management in childhood is controversial. Although in most cases only the prepuce is affected, meatal and urethral involvement may lead to major surgical reconstruction. Therefore complete surgical excision of the affected skin is considered to be mandatory. In case of involvement, incidental histological evidence or a relapse, or when complete removal of the affected skin is not possible, a topical therapy should be implemented. In a retrospective analysis of our study population (13 children) with BXO, relapse rate was lower after topical therapy with tacrolimus (Protopic), a highly selective immune modulator, than after the standard anti-inflammatory therapy with betamethasone. The use of tacrolimus ointment is a safe therapy with no severe side effects. Due to the fact that there are no predictive factors for progression or relapse of BXO, we consider a topical anti-inflammatory therapy is always indicated after any type of surgery for BXO. Follow-up monitoring should be close, so that any relapse can be detected and treated as early as possible.

Background: The treatment of urethral strictures represents an unsolved urological problem., Patients and Methods: The effect of a (32)P-coated urethral catheter in the sense of low-dose rate brachytherapy to modulate wound healing will be analyzed in an animal experiment., Results: Unfortunately it is not possible to present any results because this is being studied for the first time and there are no experiences with low-dose rate brachytherapy and this form of application in the lower urinary tract. Furthermore the animal experiment will only start in the near future. Both decade-long experiences with radiotherapy to treat benign diseases and our own results of previous studies in otolaryngology and ophthalmology let us expect a significantly lower formation of urethral strictures after internal urethrotomy., Conclusion: This study will contribute to improving the treatment of urethral strictures as demanded in previous papers.

With the involvement of clinical reconstructive urology in the field of tissue engineering, outstanding results have been achieved in basic research as well as in some clinics. Stem cell research has even opened up possibilities for regenerative aspects. In close cooperation with various disciplines, the Department of Urology at the University of Tübingen investigates different clinical aspects with regard to reconstructive and regenerative urology. The regeneration of the external urethral sphincter requires functionally integrated muscle cells. In addition stricture reconstruction with multilayer urothelium should become less invasive and the re-stricture rate reduced. After the application of differentiating stem cells was proven, the clinical setting needed to be set for legal issues. In addition to the specification of culture media and verification in the animal model, the possibility to harvest omnipotent stem cells out of human testis and to differentiate those into the three germ layers was demonstrated. With the reduced invasiveness of harvesting the urothelium cells by a bladder wash using specific culture fluids, the cell culture was significantly improved enabling successful creation of urothelium by stratification. In addition urothelial cells in a matrix are further improved for endoscopic application. The close cooperation of different disciplines shortens the time to develop therapeutic approaches with a close clinical relationship in reconstructive and regenerative urology.

In this study, an animal model was developed for the examination of urethral strictures (US). Through a resectoscope, a resection was made in the urethras of 15 male rabbits. After 30 days, the rabbits were evaluated with urethrography, impedance planimetry and either histology or the determination of collagen content. Fifteen rabbits serving as controls were evaluated in the same way. Three rabbits in the resection group and one in the control group died before evaluation. Urethrography demonstrated a stricture in the remaining 12 animals in the resection group. The urethras of the control animals were all normal. Impedance planimetry confirmed that the luminal cross sectional area (CSA) of the strictures was significantly smaller than the CSA of the corresponding part of the urethra in the control group. No difference in CSA was found 1 cm proximal to the stricture. The strictures consisted of densely woven collagen which sent tongues into the adjacent normal parts of the urethra. No difference in collagen content was found between the two groups either at the stricture site or 1 cm proximally. The described method of producing US in the rabbit model was very consistent with all operated animals developing a stricture. The model might prove valuable in evaluating new methods for the treatment of US.

We evaluated the effect of the somatostatin analogue lanreotide on the development of surgically induced experimental strictures in the anterior urethra of the male rabbit. A total of 74 male rabbits were randomly allocated into four groups. Lanreotide was administered to the rabbits in groups 2 and 4 from day 0 to 14. To create a stricture, a resection was made in the urethra of the rabbits in groups 3 and 4 on day 2. On day 30, all rabbits were examined with urethrography, impedance planimetry and either histology or for collagen content. Urethrography and impedance planimetry demonstrated a urethral stricture in all operated animals. No difference was found between the two stricture groups, regardless of lanreotide administration, with respect to luminal cross-sectional area (CSA), circumferential tension-strain relation, histology or collagen content. The CSA of the urethra of the normal controls treated with lanreotide was smaller than the CSA of the normal controls not treated with lanreotide, however, no difference was found in histology or collagen content. Lanreotide had no measurable effect on the development of a surgically induced stricture in the male rabbit anterior urethra, however, lanreotide seems to exert an inhibitory effect on the normal growth of the urethra.

The authors have analyzed the most recent additions to the literature of immunohistochemical and molecular assessment of acquired urethral strictures and report on their data obtained in a selected clinical series. Innovative immunohistochemical studies in patients presenting with plurirecurrent symptoms suggest that urethral mesenchymal changes caused by tissue de-epithelialization may be the underlying cause of stricture. This condition may be congenital or acquired. It may determine aberrant connective tissue formation induced by abnormal fibroblastic activation with formation of over abundant hyperdense collagen scar tissue.

The use of free buccal mucosal grafts in the treatment of urethral strictures has become very popular. In 1996 and 1997 we harvested free buccal mucosal grafts up to 7 cm long and 4 cm wide from 12 patients who underwent urologic surgery for urethral strictures. In 2 patients the donor site was closed primarily by sutures. Four patients received Lyodura and another 4 patients received Syspurderm as temporary wound coverage. In 2 patients Ethisorp patches were used. Donor site pain was judged by the patients on a visual analogue scale during the first postoperative week. The 2 patients who received the Ethisorp patches complained of more intense pain, probably caused by the rigidity of the material. In all patients regeneration of the donor site mucosa was good. During the follow-up period of 4-18 months scar formation at the lower vestibulum was noticed as the only complication. Permanent limitation of mouth opening, stenosis of the parotid duct or hypesthesia did not occur.

No information has been available to date on the long-term behavior of nitinol (nickel-titanium alloy) urethral stents. In the present study, prostheses of this type were implanted in 18 German shepherd dogs in order to evaluate the reaction of the mucosa, muscles and periurethral tissue. Follow-up examinations performed after 1 week, and 1, 3, 6, 12 and 18 months included urine, macroscopic, radiologic, histologic and scanning electron microscopic analyses. Despite the excellent biocompatibility of the material, with no evidence of foreign body reactions or corrosion, there were no complete incorporations of the stent by epithelialization. Clinical application therefore appears to be problematic.

The new method of urethral sonography allows visualization of urethral strictures preoperatively in more detail than conventional X-ray urethrogram. Poor results of urethrotomies can thus be avoided in patients who have peristrictural scars. These patients can be treated by the newly developed technique of laser incisions of urethral strictures. The success rate is so promising that wall-stent implantations and even open procedures may well become very rare. Diagnostic and therapeutic techniques are discussed and described in detail with reference to illustrations.