Tubularized urethral reconstruction using everted saphenous vein graft in a beagle model

Background A long segment stricture in the anterior urethra is a challenge in urology. We conducted a study to investigate the efficacy of anterior urethral reconstruction using an everted saphenous vein graft (SVG) in a tubular fashion. Methods Twelve male beagles were randomly divided into three groups: experimental group (n = 5), control group (n = 5) and normal group (n = 2). A 3 cm defect in the anterior urethra was created. Autologous SVG was harvested. In the experimental group, urethral defect was replaced by an everted SVG in a tubular fashion. In the control group, urethral reconstruction was performed using an uneverted SVG. Beagles in all groups received retrograde urethrography to evaluate urethral patency and were killed for histological examination 6 months after operation. Results Four beagles in the experimental group had no voiding difficulty and the other one could not void spontaneously. Retrograde urethrography showed the four beagles in experimental group had wide urethral lumens. Ether urethral stricture or fistula were detected in all animals in the control group. Histological analysis of the four beagles in the experimental group indicated the everted SVG completely integrated into the urethra. The reconstructed urethra contained a wide lumen and was completely covered by urothelium. The periurethral collagen and muscle fibers formed and were highly organized. Everted SVG showed a high ability of neovascularization. In the control group, the reconstructed segment showed a fibrotic urethral lumen where the urothelium was not intact. Only few new capillaries were formed. Conclusions Everted SVG demonstrates for a promising strategy for potential urethral stricture repair.

Clinical efficacy of retrograde urethrography-assisted urethral catheterization after failed conventional urethral catheterization

Background Several approaches for urethral catheterization after the failure of initial urethral catheterization have been introduced. However, standard procedures regarding what should be done after failed conventional urethral catheterization have been not established. Therefore, we investigated the clinical efficacy of retrograde urethrography (RGU)-assisted urethral catheterization after failed conventional urethral catheterization. Methods Between July 2015 and July 2018, 136 patients who underwent RGU-assisted urethral catheterization after failed conventional urethral catheterization were included in this retrospective study. Patients’ clinical data, such as age, catheterization site, and previous history of urologic operations, were collected and assessed via chart review. Univariate and multivariate logistic regression analyses were performed to identify predictive factors for the failure of this procedure. Results Of the 136 patients, 94 (69.1%) experienced successful RGU-assisted urethral catheterization. Having a previous history of urologic operations, such as urethrotomy and transurethral prostatectomy, was identified as an independent predictive factor for the failure of RGU-assisted urethral catheterization (odds ratio = 9.453, 95% confidence interval = 2.703–33.063, p < 0.001). Conclusions RGU-assisted urethral catheterization can be one of the modalities for providing successful catheterization after failed conventional urethral catheterization. We believe that RGU-assisted urethral catheterization can be an effective procedure if patients have no previous history of urologic operations, such as urethrotomy and transurethral prostatectomy. Trial registration Soonchunhyang university institutional review board approval (No. 2018-08-021).

A New Technique for Computed-Tomography Urethrography in Males: The Clamp Method

The aim of the present study is to describe and evaluate a new technique for performing Computed-Tomography Retrograde Urethrography (CT-RUG). Males with urethral anomalies detected by retrograde urethrography (RUG) and/or retrograde sonourethrography (RSUG) underwent CT-RUG using the clamp method and three radiologists evaluated the anomalies in each technique separately and blindly. CT-RUG was done successfully in all the cases (n = 22), with means of 6 min duration and 95 mL of contrast; no pain was reported by 81% of the patients (VAS: 0) and very mild pain by the rest (VAS: 0.5–1.2). CT-RUG showed better diagnostic efficacy in cases of periurethral fistula (n = 8), urethral stent (n = 3), previous urethroplasty and urethral lithiasis (n = 2), a similar accuracy to RSUG for measuring the length of anterior urethral strictures (n = 9) and greater accuracy than RUG (p = 0.008). Six cases received 2 CT sweeps, with an effective dose of 4.96 mSv, and the remaining 16 had 1 sweep and received 3.456 mSv. To the best of our knowledge, this is the first study to describe the clamp method for CT-RUG, a method that is effective and comfortable for both the patient and the operator (retrograde infusion of contrast).

Retrograde urethrosonography with SonoVue in strictures of the male urethra: a pilot study

Aim: To evaluate the effectiveness of SonoVue urethrosonography in diagnosing the adult male anterior urethral strictures pathology in comparison with retrograde urethrography.Material and method: We standardised the method and performed a comparative study evaluating the diagnosis of urethral strictures using retrograde urethrography and retrograde ultrasonographic exploration with SonoVue on 6 male patients.Results: In all patients, the existence of urethral stricture, localization and its extension were confirmed. Contrast-enhanced ultrasonographic exploration brought additional categories of information: the degree of spongiofibrosis, the elasticity of the urethral walls and the presence of urethral lithiasis. There were no periprocedural incidents.Conclusion: This pilot study demonstrates the feasibility and innocuity of urethral ultrasound with SonoVue. Real-time ultrasound exploration highlights aspects that are not seen in radiological examination, so the method can be complementary or alternative to this procedure.