The use of urethral stents for the treatment of urethral strictures

Three types of urethral stents can be used in the treatment of recurrent strictures: Urolume/Wallstent is a self-expanding mesh which is incorporated into the urethral epithelium; the ASI Titanium stent is a short rigid mesh of Titanium wire which is also incorporated into the urethra; Nitinol is a flexible spring in one or two parts connected by a steel wire. It remains endoluminal. The Urolume/Wallstent has been used since 1987. It is indicated in iatrogenic strictures. No statistical results are presented. The ASI stent should be reserved for strictures of the prostatic and posterior urethra. The Niticol UroCoil system can be used at all levels of the urethra; two models are available: simple or twin. The author has inserted 65 stents in 56 patients. The stent was removed after one year in 41 patients. The use of these stents has considerably decreased the number of repeated dilatations and urethrotomies.     

The surgical repair of membranous urethral strictures in children

The origin of the Maudsley reactive and nonreactive strains of rats and the construction of the survey of researches using them are briefly reviewed in the light of Archer's criticisms. The reasons for reasserting that they represent a valid dichotomy in emotionality are summarized.     

Onlay island flap urethroplasty in the treatment of urethral strictures

A skin island flap was used to create a neourethra in 65 patients aged 2 to 66 years with prolonged or multiple stricture of the anterior urethra. Before, all patients were treated repeatedly and unsuccessfully by open or endoscopic surgery. The principle of the used onlay technique was to supplement the missing lumen of the urethra by an island, usually preputial flap. In case of as missing segment of the urethra the original inlay-onlay technique was applied. After a mean follow-up period of 27 months 12 complications (18.4%) were recorded, six strictures of the proximal anastomosis, three fistulas and three dehiscences of the glans. CONCLUSION: The onlay island flap urethroplasty makes it possible to cure prolonged and multiple strictures of the urethra in one stage and with a relatively low complication rate.     

Prenatal sonographic diagnosis of posterior urethral valves: identification of valves and thickening of the posterior urethral wall

This report describes 2 heretofore unreported sonographic findings that may aid in the antenatal diagnosis of posterior urethral valves. Each of 2 fetuses showed a prominent or thickened posterior urethra and one or more bright echogenic lines representing valve tissue within a dilated and/or thickened posterior urethra. These findings helped solidify the antenatally suspected diagnosis of posterior urethral valves. The diagnosis was confirmed clinically and surgically during neonatal life. These 2 imaging findings may help in providing a more definitive antenatal diagnosis of posterior urethral valves and allow more expeditious therapy.     

The "Wallstent": a new stent for the treatment of urethral strictures

Morphine or morphine-6-glucuronide either alone or in combination with morphine-3-glucuronide was administered intrathecally to rats. Antinociceptive effects were evaluated with the tail flick and the hot plate tests. Motor function was tested using the rotarod test. Estimated ED50 from the dose-response curves for morphine and morphine-6-glucuronide showed about a 30 times more potent antinociceptive effect of morphine-6-glucuronide compared with morphine. Morphine-3-glucuronide had no antinociceptive effect. Simultaneous administration of morphine-3-glucuronide 5.0 micrograms did not show any significant effect on antinociception induced by morphine 1.0 microgram or morphine-6-glucuronide 0.05 microgram.     

Use of multiple urolume endourethral prostheses in complex bulbar urethral strictures

PURPOSE: We evaluated patients who received multiple UroLume Wallstents during the North American UroLume trial for the treatment of recurrent bulbar urethral strictures. MATERIALS AND METHODS: A total of 41 patients received multiple UroLume stents. The clinical histories and therapeutic outcomes of these patients were reviewed. RESULTS: Of the patients 23% required placement of multiple urethral stents. Stents placed at the initial procedure were required for strictures longer than 2.5 cm. and for multiple, separate strictures. Indications for secondary insertion included recurrent stricture adjacent to the stent, hyperplastic tissue growth within the stent and gaps between previously adjacent stents. The repeat treatment rate was 43.9% versus 14.3% for the study group overall. Urine flow rates and symptom scores in the multiple stent group showed improvement similar to that of the study group overall. CONCLUSIONS: Patients who required multiple stents had greater rates of repeat treatment but similarly improved urine flows and symptom scores, which were maintained at 2 years.     

Management of obliterative posttraumatic posterior urethral strictures after failed initial urethroplasty

PURPOSE: We evaluate the problems encountered during surgery and assess the results of different endoscopic and open surgical methods following failed urethroplasty for posttraumatic posterior urethral stricture. MATERIALS AND METHODS: Since 1992 we have treated 23 patients in whom urethroplasty for posterior urethral strictures failed. Of these patients, 3 had undergone 2 previous repairs and 6 had additional complicating factors, such as fistula, periurethral cavity and false passage. End-to-end anastomosis was done in 14 patients via a transperineal (7) or transpubic (7) approach. In 1 patient substitution urethroplasty using a radial artery based forearm free flap was performed. In 3 patients a 2-stage urethroplasty was done, 4 underwent core-through optical internal urethrotomy and 1 underwent endoscopic marsupialization of a false passage. RESULTS: At 1 to 5-year followup 3 of the 23 patients had restenoses (13%), including 2 in whom previous treatment failed. The remaining 87% of the patients void well and are continent, and there is no worsening of the preexisting potency status. CONCLUSIONS: Previous failed urethral stricture repair complicates management due to fibrosis, impaired vascularity and limited urethra available for mobilization. Recurrent strictures less than 1.5 cm. can be managed successfully with core-through internal urethrotomy. End-to-end anastomosis is possible in the majority with generous use of inferior pubectomy or the transpubic approach with certain modifications. When residual inflammation or long strictures are present a 2-stage procedure is a safer option. Overall, reoperation can offer a successful outcome for the majority of these complex strictures.     

Long-term results of intermittent low-friction self-catheterization in patients with recurrent urethral strictures

OBJECTIVE: To ascertain the duration of intermittent low-friction self-catheterization (ILSC) required to cause stricture stabilization. PATIENTS AND METHODS: Over a 4 year period, 101 patients with a median age of 62 years (range 16-85) with recurrent urethral strictures were recruited to the trial. All the strictures were treated by internal urethrotomy and the patients were then randomized to perform ILSC twice weekly for either 6 months (group 1) or 36 months (group 2). Out-patient follow-up with urinary flow rate was initially at 1 month and then at 3 monthly intervals. Stricture recurrence rates were compared between the two groups. RESULTS: Of 101 patients, seven failed to attend after the first out-patient appointment. A further 21 died of unrelated disease whilst on ILSC (although 13 had been followed up for at least 24 months and so were included in the analysis). The median follow-up was 67 months (range 24-78). Ten patients in group 2, who had suffered from recurrent strictures, refused to stop catheterizing at the appointed time and all remain stricture-free on permanent ILSC. Of the remaining 76 patients, 48 catheterized for 6 months and 28 patients performed ILSC for 12 to 36 months (nine stopped earlier than intended). Forty per cent of patients who stopped at 6 months developed a recurrence compared with 14% who catheterized for more than 12 months (P < 0.05) (chi-square test with Yates' correction). CONCLUSIONS: Our results indicate that ILSC is safe and effective in preventing stricture recurrence in the long term. The recurrence rate of urethral strictures was significantly lower when ILSC was continued for more than 12 months compared with ILSC that was stopped at 6 months. We conclude that catheterization for at least 1 year is required to achieve adequate urethral stabilization.     

The endoscopic treatment of extensive urethral strictures and obliteration of the urethra and bladder neck

Extensive urethral strictures, obliteration of the urethra and bladder cervix are thought to be the most complicated urological diseases. They occur more frequently in young and middle-aged persons consequently to pelvic and perineal traumas or they are complications of surgical interventions. Open surgery often cause complications such as suppuration of the operative wound, emergence of urinary fistulas, enuresis, recurrence of the structure or obliteration. Negative results of these operations are also shortening of the penis, erectile dysfunction causing serious social dysadaptation. Current advances in endoscopic instruments and imaging provided design of endoscopic techniques able to represent an effective alternative to open surgical interventions in urethral strictures, obliteration of the urethra and bladder cervix. The experience gained in the Clinic of the Research Institute of Urology in the practice of updated and novel endoscopic interventions aimed at recovery of urethral patency (strictures longer than 1 cm--inner optic urethrotomy, obliteration of the urethra and bladder cervix--endoscopic recanalization) has proved the advantages of the endoscopic techniques over open operative interventions. They are most cost-effective, result in better outcomes, bring about no erectile dysfunction.     

Transrectal sonographic investigation of urethral and paraurethral structures in women with stress urinary incontinence

Transrectal sonography of the urethra was used in 14 asymptomatic volunteers, 37 women with frequency-urgency syndrome, 42 patients with mild stress urinary incontinence, and 18 with severe stress urinary incontinence. Transverse scanning over the midurethra was performed and cross-sectional images of the urethral and paraurethral structures were compared among the four groups, with P < 0.05 being considered statistically significant. The total cross-sectional area of the midurethra was significantly smaller in patients with stress urinary incontinence than in those without this disorder (86.7+/-29.9 versus 104+/-35.6 mm2, P = 0.005); this difference resulted from a significantly smaller peripheral striated muscle component in patients with stress urinary incontinence (42.8+/-20.7 versus 58.3+/-27.3 mm2, P = 0.001). The thickness of the urethropelvic ligaments was significantly thinner in patients with stress urinary incontinence than in those without (5.9+/-1.7 versus 8.9+/-2.1 mm, P < 0.001). The distribution of the peripheral striated muscle around the urethra was variable: complete surrounding the urethra was noted in 35.7% of the control women and in 48.6% of frequency-urgency patients, but only in 16.7% of patients with mild stress urinary incontinence and 5.3% of patients with severe disease. Bladder neck incompetence was seen in 42 patients with stress urinary incontinence but in none of the control women. The length of the pubourethral ligaments was similar in the four groups. Our finding showed that stress urinary patients had a smaller striated muscle component in the midurethra and thinner urethropelvic ligaments. These defects in the continence mechanisms might have great implications in the pathophysiology of stress urinary incontinence. Transrectal sonography of the urethra is a valuable investigative tool in assessing urethral and paraurethral conditions in patients with stress urinary incontinence before deciding treatment modality.     

Treatment of male urethral strictures: is repeated dilation or internal urethrotomy useful?

PURPOSE: We evaluate the efficacy of repeated dilation or urethrotomy as treatment of male urethral strictures. MATERIALS AND METHODS: Between January 1991 and January 1994, 210 men with proved urethral strictures were prospectively randomized to undergo filiform dilation (106) or internal urethrotomy (104). Followup was scheduled at 3, 6, 9, 12, 24, 36 and 48 months. Dilation or internal urethrotomy was repeated at the first and second stricture recurrence. The Kaplan-Meier method was used to estimate survivor function for the treatment methods (survival time being the time to first stricture recurrence) and the log rank test was used to compare the efficacy of different treatments. RESULTS: Followup (mean 24 months, range 2 to 63) was available in 163 patients (78%). After a single dilation or urethrotomy not followed by re-stricturing at 3 months, the estimated stricture-free rate was 55 to 60% at 24 months and 50 to 60% at 48 months. After a second dilation or urethrotomy for stricture recurrence at 3 months the stricture-free rate was 30 to 50% at 24 months and 0 to 40% at 48 months. After a third dilation or urethrotomy for stricture recurrence at 3 and 6 months the stricture-free rate at 24 months was 0 (p <0.0001). CONCLUSIONS: Dilation and internal urethrotomy are useful in a select group (approximately 70% of all patients) who are stricture-free at 3 months, and of whom 50 to 60% will remain stricture-free up to 48 months. A second dilation or urethrotomy for early stricture recurrence (at 3 months) is of limited value in the short term (24 months) but of no value in the long term (48 months), whereas a third repeated dilation or urethrotomy is of no value.     

Penile circular fasciocutaneous skin flap in 1-stage reconstruction of complex anterior urethral strictures

PURPOSE: We review the applications and outcomes of penile circular fasciocutaneous flap urethroplasty in 66 patients at our institution. MATERIALS AND METHODS: We used a circular distal penile skin flap for urethral reconstruction in 66 men with complex urethral strictures. Average stricture length in this series was 9.08 cm. and mean followup was 41 months (range 1 to 7 years). RESULTS: The initial overall success rate was 79% (52 of 66 cases). Recurrent stenosis was noted in 7 of the 54 onlay (13%) and 7 of the 12 tubularized repairs (58%). Most recurrent strictures were successfully treated with a single subsequent procedure, including repeat urethroplasty in 5 cases and optical urethrotomy or dilation in 6. Two patients required perineal urethrostomy and 1 awaits further reconstruction. Including subsequent procedures, the overall long-term followup success rate was 95%. Neurovascular lower extremity complications developed in 4 patients after prolonged high lithotomy positioning. CONCLUSIONS: Circular fasciocutaneous flap urethroplasty is a highly effective 1-stage method of reconstructing complex urethral strictures. Onlay repairs appear to be more successful than those involving flap tubularization. Limiting the time that the patient spends in the high lithotomy position appears to prevent neurovascular extremity complications.     

Comparison of two question sequences for assessing pregnancy intentions

Unintended pregnancies can have serious health, social, and economic consequences. Such pregnancies may be unwanted (a baby is not wanted at any time) or mistimed, yet wanted (a baby is wanted eventually). Intended pregnancies are those conceived when desired. Reproductive health survey respondents' understanding of these concepts and validity of survey results may be affected by question order and wording. Using a randomized crossover design, National Survey of Family Growth (NSFG) and Demographic and Health Survey (DHS) intendedness questions were asked in a 1993 survey of Arizona women aged 18-44 years. Of 2,352 ever-pregnant respondents, 25% gave discordant responses to DHS and NSFG questions about the most recent pregnancy. Age, marital status, household income, education, parity, time since pregnancy, and outcome of pregnancy were significantly predictive of discordant responses. DHS and NSFG questions yielded similar prevalence estimates of intendedness and wantedness; but young, unmarried respondents gave more "mistimed" responses on whichever question was asked later. Classifying pregnancies as intended, mistimed, or unwanted may be a problem for women who have not decided on lifetime reproductive preferences. Approaches to improving survey validity include addressing ambivalence, clarifying the definition of "unwanted," and, for young, unmarried women, not attempting to classify unintended pregnancies as mistimed or unwanted.     

The sonographic and computed radiographic findings in perigraft reactions after the surgical implantation of vascular prostheses

Between January 1988 and January 1994, 24 patients with heterologous vascular bypasses were examined with suspected diagnosis of a perigraft reaction (PGR). All patients were subjected to ultrasound and CT. PGR ist defined as a sterile inflammation along the course of a vascular prosthesis. The typical clinical presentation is a fluctuating tumour with a localised painless swelling. In all cases liquid formations could be confirmed by diagnostic imaging procedures; signs of infection could be excluded. The synopsis of the clinical presentation, the time interval after implantation of the prosthetic material and the signs of sonography and CT can reliably exclude infection of the prosthesis and confirm the diagnosis of a PGR.     

Comparison of urethral swabs, urine, and urinary sediment for the isolation of Chlamydia

In 70 male patients with urethritis, Chlamydia was recovered from 18 urethral swabs (26%), 5 urinary sediments (7%), and 3 urine specimens (4%). All Chlamydia isolates were recovered from urethral swabs.     

Metal stents for benign and malignant bile duct strictures stents for benign and malignant bile duct strictures

Self-expanding metal stents provide a much larger diameter--up to 30 Fr--in comparison with plastic stents, which have a maximum diameter of 12 Fr. Although they have consequently been found to be far superior to plastic prostheses, they are not removable, and in benign strictures metal stents should therefore be used only in exceptional situations. Metal stents are the preferred mode of treatment for malignant strictures, provided the patient has a sufficient life expectancy although this is hard to predict in individual cases. Metal stents also seem to be superior in hilar malignancy, but the data here are limited. Future developments may include the use of covered metal stents and self-expanding stents (made of plastic or other materials) that are removable or self-dissolving.     

Comparison of two tests and absorbance at 650 nm for assessing fetal lung maturity

The clinical performance of three rapidly performed tests--tap test, TDx Fetal Lung Maturity and amniotic fluid absorbance at 650 nm--in predicting fetal lung maturity were evaluated in 300 samples of clear amniotic fluid. In all cases, delivery occurred within three days of sample collection. Of the 300 newborns, 44 developed respiratory distress syndrome. For the tap test, the sensitivity (95.4%), specificity (82.8%), and predictive value for maturity (99.7%) and immaturity (48.9%) were comparable to those of the TDx fetal lung maturity test: sensitivity of 100%, specificity of 88.3%, and predictive value for maturity of 100% and immaturity of 53.1%. The specificity (68.4%) and predictive value for immaturity (34.7%) of amniotic fluid absorbance at 650 nm were significantly lower than for the TDx and tap tests, whereas no significant difference was found for sensitivity and prediction of maturity between amniotic fluid absorbance at 650 nm and the TDx and tap tests. Both the tap and the TDx tests appear to be useful in antenatal assessment of fetal lung maturity in terms of reliability, rapidity and uniformity.     

Comparison of passive urethral resistance relation and urethral resistance factor in analysis of bladder outlet obstruction in patients with benign prostatic enlargement

Analysis of the pressure/flow relation renders objective and detailed information on bladder outlet obstruction. The benefit of pressure/flow analysis for clinical and fundamental research questions, however, cannot be acknowledged without comparison of the different methods that exist. We compared one parameter analysis (URA) with two parameter (PURR) analysis in 99 consecutive patients with benign prostatic enlargement. The normal (instantaneous intrapatient) variability of both the PURR parameter Pvoidmin (minimal pressure during voiding) and the URA is approximately 10-15 cm H2O. Within these limits agreement between the two methods of analysis in the quantification of (minimal) outlet obstruction was observed in about 50% of the cases. However, when Qmax is less than 6 ml/s (in 49.5% of the patients) the URA number exceeds the value Pvoidmin in 96% of the cases. Predominantly this is caused by the fact that in the majority of these cases the type of bladder outlet obstruction is more constrictive than the URA curve, based on Pdet at Qmax indicated. In patients with a low flow rate and/or a constrictive type of obstruction, the Pvoidmin resulting from PURR analysis indicates a lower minimal pressure during voiding compared to URA.     

MR angiographic and sonographic indications for endarterectomy

This study describes a HPLC method to determine the concentrations of acetylsalicylic acid (ASA) and salicylic acid (SA) in human stratum corneum and in plasma. The stratum corneum layers for ASA/SA analysis were removed from three patients with postherpetic hyperalgesia treated with topical and oral aspirin. Blood samples were also collected from the same patients. Tape strippings were placed in acetonitrile and sonicated for 15 min. After centrifuging, aliquots of the supernatant were injected into the chromatograph. ASA and SA from plasma samples were extracted on Isolute C8 columns. Due to interfering peaks in the tape samples, HPLC conditions were slightly different for tape and plasma samples. ASA and SA were separated on a LiChrospher 100 RP-18 column at 1 ml/min using a water-phosphate buffer (pH 2.5)-acetonitrile mobile phase (35:40:25, v/v/v). A linear response to quantities of ASA from 0.1 to 100 microg/cm2 and of SA from 0.1 to 5 microg/cm2 in tape and to quantities of ASA 0.1 to 2 microg/ml and 1 to 50 microg/ml was obtained and the recovery from tape and plasma samples was over 98%. The method is sensitive (0.1 microg/cm2) and specific enough to allow the determination of the drugs in the skin not only after topical but also after oral administration. A good sensitivity was also obtained in plasma (0.1 microg/ml) allowing study of the kinetics of ASA and SA in plasma after oral administration. Concentrations of ASA after topical administration were 100-200 times higher than after oral administration. Plasma levels of ASA and SA after oral administration were similar to those previously found. No ASA or SA were detected in plasma after topical ASA administration.     

Validation of a recording protocol for assessing temporomandibular sounds and a method for assessing jaw position

This purpose of this study was to examine the relationship between exposure to wheat flour, soya flour and fungal amylase and the development of work-related symptoms and sensitization in bread and cake bakery employees who have regular exposure to these substances. The study populations consisted of 394 bread bakery workers and 77 cake bakery workers whose normal jobs involved the sieving, weighing and mixing of ingredients. The groups were interviewed with the aim of identifying the prevalence, nature and pattern of any work-related respiratory symptoms. They were also skin-prick tested against the common bakery sensitizing agents, i.e., wheat flour, soya flour, rice flour and fungal amylase. The results of personal sampling for sieving, weighing and mixing operations at the bakeries from which the study groups were taken were collated in order to determine typical exposures to total inhalable dust from the ingredients, expressed as 8 hour time-weighted average exposures. Data from the health surveillance and collated dust measurements were compared with the aim of establishing an exposure-response relationship for sensitization. The prevalence of work-related symptoms in bread bakery and cake bakery ingredient handlers was 20.4% and 10.4% respectively. However, in a large proportion of those reporting symptoms in connection with work, the symptoms were intermittent and of short duration. It is considered that the aetiology of such symptoms is likely to be due to a non-specific irritant effect of high total dust levels, rather than allergy. None of the cake bakers and only 3.1% of the bread bakers had symptoms which were thought to be due to allergy to baking ingredients. Using skin-prick testing as a marker of sensitization, the prevalence of positive tests to wheat flour was 6% for the bread bakers and 3% for the cake bakers. Comparable prevalences for soya flour were 7% and 1% respectively. However, the prevalence of positive skin-prick tests to fungal amylase was 16% amongst the bread baking group with only a single employee (1%) in the cake baking group having a positive test. Furthermore, this employee had previously worked in a bread bakery. The difference in rates of sensitization to wheat flour between the bread and cake bakers is not statistically significant, whereas the difference for soya flour is at the borderline of statistical significance (p = 0.045). In contrast, the difference in fungal amylase sensitization is significant at the 0.1% level. For both bread and cake bakers, the 8 hour time-weighted average exposures for each of the activities showed a wide variation with mixing having the lowest average exposure and sieving the highest. Out of the allergens studied in this investigation, fungal amylase is the principal sensitizer in large scale bread bakeries, with the main source of exposure being the handling of bread improvers. In contrast, the risk of sensitization to wheat flour is low in both bread and cake bakeries. The absence of positive skin-prick tests in the subgroup of cake bakery employees who regularly handle fungal-amylase-containing flour suggests that their levels of exposure are below the threshold for sensitization to amylase.