Functional evaluation of anterior urethral strictures with combined antegrade and retrograde urethrography

SIU/ICUD Consultation on Urethral Strictures: Evaluation and follow-up

For the 2010 International Consultation on Urethral Strictures, all available published data relating to the evaluation and follow-up of patients with anterior urethral stricture or posterior urethral stenosis were reviewed and evaluated. Selected manuscripts were classified by Level of Evidence using previously established criteria. Consensus was achieved through group discussion, and formal recommendations were established and graded on the basis of levels of evidence and expert opinion. Retrograde urethrography remains the de facto standard for the evaluation of patients with urethral stricture. It can readily be combined with voiding cystourethrography to achieve a synergistic evaluation of the entire urethra, and this approach is currently recommended as the optimal method for pretreatment staging. Cystoscopy is recommended as the most specific procedure for the diagnosis of urethral stricture and is a useful adjunct in the staging of anterior urethral stricture, particularly to confirm abnormal or equivocal findings on imaging studies. Cystoscopy is also an important modality for assessing the bladder neck and posterior urethra in the setting of a pelvic fracture-related urethral injury. Although urethrography and cystoscopy remain the principle forms of assessment of the patient with urethral stricture, additional adjuncts include uroflowmetry, symptom scores, quality of life assessments, ultrasonography, computed tomography, and magnetic resonance imaging. These modalities might be helpful to further evaluate patients in select circumstances or provide a less invasive approach to monitoring outcomes after surgical treatment. Further research is needed to establish consensus opinion as to the definition of success after urethroplasty and to develop standardized patient outcome measures.

Prospective evaluation of a new visual prostate symptom score, the international prostate symptom score, and uroflowmetry in men with urethral stricture disease

OBJECTIVE

To evaluate the correlation between the visual prostate symptom score (VPSS) and the international prostate symptom score (IPSS) and uroflowmetry parameters in men with urethral stricture disease. The VPSS offers a nonverbal, pictographic assessment of lower urinary tract symptoms.

METHODS

A total of 100 men followed up with a diagnosis of urethral stricture were evaluated from March 2011 to November 2012 with IPSS, VPSS, uroflowmetry, urethral calibration, and urethrography. Follow-up every 3 months for 3-18 months was available in 78 men for a total of 289 visits. Procedures performed were urethral dilation in 105, internal urethrotomy in 54, and urethroplasty in 8 patients. Statistical analysis was performed with Spearman's rank correlation, Fisher's exact, and Student t tests.

RESULTS

The time taken to complete the VPSS vs IPSS was significantly shorter (118 vs 215 seconds at the first and 80 vs 156 seconds at follow-up visits; P <.001). There were significant correlations between the VPSS and IPSS (r = 0.845; P <.001), maximum urinary flow rate (Qmax; r = 0.681; P <.001) and urethral diameter (r = -0.552; P <.001). A combination of VPSS >8 and Qmax <15 mL/s had positive and negative predictive values of 87% and 89%, respectively, for the presence of urethral stricture.

CONCLUSION

The VPSS correlates significantly with the IPSS, Qmax, and urethral diameter in men with urethral stricture disease and takes significantly less time to complete. A combination of VPSS >8 and Qmax <15 mL/s can be used to avoid further invasive evaluation during follow-up in men with urethral strictures.

Urethral ultrasound as a screening tool for stricture recurrence after oral mucosa graft urethroplasty

OBJECTIVE

To evaluate the efficacy of sonourethrography (SUG) in combination with voiding pattern analysis to determine success after oral mucosa graft (OMG) urethroplasty. OMG urethroplasty is a standard treatment for men with recurrent urethral stricture. Because of its performance, the optimum follow-up algorithm remains controversial.

MATERIAL AND METHODS

Forty-nine patients (mean age 51 years) who underwent OMG urethroplasty were retrospectively identified. All men were subjected to a validated voiding questionnaire (International Prostate Symptom Score [IPSS]), SUG, uroflowmetry, and residual urine measurement. The predictive value was analyzed with regard to stricture recurrence or patency as well as to urethral diameter. Retrograde urethrography was done to confirm the diagnosis.

RESULTS

Strictures were bulbar in 39, penile in 4, and combined in 6 patients. Mean stricture length was 3.8 cm (range 1-10). Mean follow-up after surgery was 35 (range 15-70) months. SUG showed a mean diameter of 7.6 mm for bulbar grafts and 4.6 mm for penile grafts. Stricture recurrence was seen in 4 (8%) patients, yielding a significantly lower urethral width of 2.3 mm (P<.005). Retrograde urethrography confirmed the patency status in all. The average maximum flow rate after successful repair was 36.6 mL/s, whereas those with recurrent strictures showed rates of 11.2 (P<.03). Similar results were achieved for residual urine (P<.05). IPSS values increased from 5.1 to 12.5 in patients with recurrence (P<.01).

CONCLUSION

An algorithm consisting of SUG, uroflowmetry, residual urine and IPSS assessment reliably identifies stricture recurrence. Routine retrograde urethrography may therefore be unnecessary in the follow-up of OMG urethroplasty.

The use of uroflowmetry to diagnose recurrent stricture after urethral reconstructive surgery

PURPOSE

The ability of uroflowmetry to diagnose recurrent stricture disease after urethroplasty has not been fully investigated.

MATERIALS AND METHODS

Our routine post-urethroplasty monitoring includes retrograde urethrogram and voiding cystourethrogram at 3 and 12 months, in addition to uroflowmetry at 3-month intervals for a year. All uroflowmetry data, including maximum flow rate, voided volume and voiding curve shape, as well as retrograde urethrogram/voiding cystourethrogram and voiding symptom data are stored in a prospectively maintained urethroplasty database that was analyzed for patients with postoperative retrograde urethrogram/voiding cystourethrogram and satisfactory uroflowmetry in the same period. Uroflowmetry data points and urinary symptoms were compared with corresponding findings on retrograde urethrogram/voiding cystourethrogram to determine the ability of uroflowmetry to predict recurrence.

RESULTS

A total of 278 men (68%) met study inclusion criteria, of whom 63 (23%) had recurrent stricture. Using a maximum flow rate of less than 10 ml per second resulted in only 54% test sensitivity to predict recurrence. The highest sensitivity and negative predictive value (each 99%) were achieved when all men with symptoms and/or obstructed flow curves were evaluated. Symptoms alone had a high specificity (87%), sensitivity (88%) and negative predictive value (95%).

CONCLUSIONS

Uroflowmetry is an adequate test to screen for postoperative stricture recurrence but only when the voiding curve and urinary symptoms are also evaluated. The flow rate alone does not appear to be a reliable tool to evaluate stricture recurrence.

Imaging of male urethra

The male urethral imaging and pathology is not widespread in the radiology literature because this part of the urinary tract is easily studied by urologists with clinical or endoscopic examinations. Ultrasonography and MR imaging are increasingly being used in association with voiding cystourethrography and retrograde urethrography. The posterior urethra is being studied with voiding cystourethrography or voiding sonography which allows the detection of bladder neck pathology, post-surgical stenosis, and neoplasms. The functional aspects of the bladder neck and posterior urethra can be monitored continuously in patients with neuromuscular dysfunction of the bladder. The anterior urethral anatomy and pathology is commonly explored by retrograde urethrography, but recently sonourethrography and MR imaging have been proposed, distending the lumen with simple saline solution instead of iodinated contrast media. They are being used to study the urethral mucosa and the periurethral spongy tissue which can be involved in the urethral pathologies such as strictures, diverticula, trauma, and tumors. Imaging has an important role to play in the study of the diseases of the male urethra since it can detect pathology not visible on urethroscopy. The new imaging techniques in this area, such as sonography and MR, can provide adjunct information that cannot be obtained with other modalities.

Prospective evaluation of the American Urological Association symptom index and peak urinary flow rate for the followup of men with known urethral stricture disease

PURPOSE

We prospectively evaluated the American Urological Association (AUA) symptom index and maximum urine flow for predicting urethral stricture recurrence in men with a previous diagnosis of urethral stricture disease.

MATERIALS AND METHODS

Patients were recruited at our urethral stricture clinic, where all newly diagnosed and previously treated men with urethral stricture present and are treated. The AUA symptom index was completed and uroflowmetry was done. The stricture was calibrated using Jacques catheters. If an 18Fr catheter could not be passed, a retrograde urethrogram was performed. Patients were treated with filiform dilation or direct vision internal urethrotomy. Uroflowmetry was repeated when the catheter was removed 3 days later and the AUA symptom index was repeated 1 month later.

RESULTS

Data on 49 patients (170 consultations) between March 2000 and August 2001 were analyzed. Average patient age was 48 years. There was a significant negative correlation of urethral diameter with AUA symptom index and of AUA symptom index with maximum urine flow as well as a significant positive correlation of urethral diameter with maximum urine flow. We evaluated the usefulness of AUA symptom index and maximum urine flow at different cutoff levels for predicting urethral stricture in our study group. Using an AUA symptom index of greater than 10 or maximum urine flow of less than 15 ml. per second as cutoff values provided 93% sensitivity, 68% specificity, 78% positive predictive value, 89% negative predictive value and 82% overall accuracy. This method could have prevented further invasive studies in 34% of patients, while a clinically significant stricture would have been missed in only 4.3%.

CONCLUSIONS

AUA symptom index combined with maximum urine flow is an accurate, time-saving and cost-effective tool for predicting recurrent stricture in patients with a known urethral stricture. It can be used to direct decision making on further invasive studies and treatment.

Displacement sequence and elastic properties of anterior prostate/urethral interface during micturition of spinal cord injured men

The management of complex micturition problems frequently encountered in patients with spinal cord injury (SCI) may be facilitated by characterization of the elastic properties of the prostate. To this end, we have developed a method of evaluating changes in prostate biomechanics using ultrasound (US) images obtained during routine diagnostic urodynamic evaluations. Ultrasound video sequences of the prostate and urethra during voiding were digitized simultaneously with bladder pressure measurement on 76 patients with spinal cord injury, having a mean age of 47 +/- 16 years. Computer enhancement of the bladder/prostate/urethral interface from sequences of 2-D US images facilitated measurement of midprostatic urethral displacement during micturition. Of 76 patients, 21 were able to initiate voiding. Maximum urethral diameter was 12.0 +/- 1.3 mm, with corresponding maximum voiding pressure of 61.6 +/- 1.9 cmH(2)O. Urethral/prostatic pressure strain elastic modulus (Ep) was 960 +/- 624 N/m(2) and stiffness (beta) calculated as the inverse of compliance was 2.8 +/- 0.1. The diameter of the urethra at P(det50+), during the opening phase, was 0.4 +/- 0.1 mm and, during the closing phase, was 0.7 +/- 0.1 mm. During voiding, the anterior prostate was displaced to a greater extent than the posterior prostate. These observations suggest that distension of the prostate/urethra during micturition is hysteretic and nonuniform and indicates regional differences in compliance within the prostate/urethra interface. These regional differences lend support to the concept that the posterior prostate is implicated in the active process of micturition involving the fibromuscular stroma. Clinical application of this method could include quantification of the biomechanics of micturition consequent to spinal injury, prostatic enlargement, and the impact of targeted evaluation of pharmacological interventions.

The micturitional urethral pressure profile

The micturitional urethral pressure profile (MUPP) was recorded using a measuring catheter with two eyes, 250 mm apart, one for recording the bladder pressure, the other for the urethral pressure during continuous withdrawal during micturition. Fifteen normal male subjects and 48 male patients with infravesical obstruction were studied. By means of the MUPP, it was possible to determine whether the patient had an obstruction or not, to differentiate between various kinds of obstructions and to localise the obstruction in the urethra. Provided infravesical obstructions can be considered "near rigid" segments, the degree of obstruction can be calculated and expressed in terms of a diameter and an approximate resistance. The diameter and resistance values should, however, not be considered alone but be regarded as complementary to the pressure profile.