Safety and efficacy of fluoroscopy-guided urethral catheterization in case of failed blind or cystoscopy-assisted urethral catheterization.

This retrospective study evaluated the safety and efficacy of fluoroscopy-guided urethral catheterization in patients who failed blind or cystoscopy-assisted urethral catheterization. We utilized our institutional database between January 2011 and March 2023, and patients with failed blind or cystoscopy-assisted urethral catheterization and subsequent fluoroscopy-guided urethral catheterization were included. A 5-Fr catheter was inserted into the urethral orifice, and the retrograde urethrography (RGU) was acquired. Subsequently, the operator attempted to pass a hydrophilic guidewire to the urethra. If the guidewire and guiding catheter could be successfully passed into the bladder, but the urethral catheter failed pass due to urethral stricture, the operator determined either attempted again with a reduced catheter diameter or performed balloon dilation according to their preference. Finally, an appropriately sized urethral catheter was selected, and an endhole was created using an 18-gauge needle. The catheter was then inserted over the wire to position the tip in the bladder lumen and ballooned to secure it. We reviewed patients' medical histories, the presence of hematuria, and RGU to determine urethral abnormalities. Procedure-related data were assessed. Study enrolled a total of 179 fluoroscopy-guided urethral catheterizations from 149 patients (all males; mean age, 73.3 ± 13.3 years). A total of 225 urethral strictures were confirmed in 141 patients, while eight patients had no strictures. Urethral rupture was confirmed in 62 patients, and hematuria occurred in 34 patients after blind or cystoscopy-assisted urethral catheterization failed. Technical and clinical success rates were 100%, and procedure-related complications were observed in four patients (2.2%). The mean time from request to urethral catheter insertion was 129.7 ± 127.8 min. The mean total fluoroscopy time was 3.5 ± 2.5 min and the mean total DAP was 25.4 ± 25.1 Gy cm2. Balloon dilation was performed in 77 patients. Total procedure time was 9.2 ± 7.6 min, and the mean procedure time without balloon dilation was 7.1 ± 5.7 min. Fluoroscopy-guided urethral catheterization is a safe and efficient alternative in patients where blind or cystoscopy-assisted urethral catheterization has failed or when cystoscopy-urethral catheterization cannot be performed.

A novel trauma induced urethral stricture in rat model.

Urethral stricture (US) is a longstanding disease, while there has not existed a suitable animal model to mimic the condition. We aimed to establish a trauma-induced US animal model to simulate this clinical scenario. A total of 30 rats were equally distributed into two groups, sham and US group. All rats were anesthetized with isoflurane and undergone cystostomy. In the US group, a 2 mm incision was made in the urethra and sutured to induce US. The sham group only make a skin incision on the ventral side of the anterior urethra. 4 weeks later, ultrasound and cystourethrography were performed to evaluate the degree of urethral stricture, pathological examinations were carried out to evaluate the degree of fibrosis. Urodynamic evaluation and mechanical tissue testing were performed to evaluate the bladder function and urethral tissue stiffness. The results showed that the urethral mucosa was disrupted and urethral lumen was stenosed in the US group. Additionally, the US group showed elevated bladder pressure, prolonged micturition intervals and increased tissue stiffness. In conclusion, the rat urethral stricture model induced by trauma provides a closer representation of the real clinical scenario. This model will significantly contribute to advancing research on the mechanisms underlying traumatic urethral stricture.

Routine Imaging After Bulbar Urethral Reconstruction Does Not Impact Surgical Outcomes and May Not Be Necessary.

OBJECTIVE: To assess whether omitting routine post-operative imaging adversely impacts clinical outcomes after bulbar urethroplasty. Contrast imaging is commonly performed prior to catheter removal after urethroplasty but the clinical need for this is unclear. METHODS: This was a matched, case-control analysis comparing patients undergoing routine voiding cystourethrogram (VCUG) prior to catheter removal after bulbar urethroplasty to patients without imaging. Patients were matched with respect to age, stricture etiology, length, and urethroplasty technique. Follow-up consisted of clinical assessment 3 weeks post-operatively for VCUG/catheter removal, cystoscopy at 3-4 months with clinical assessment annually. Outcome measures were 90-day complications (Clavien ≥2) and stricture recurrence (failure to pass a 16-Fr flexible cystoscope on follow-up). Chi-square and Kaplan-Meier analysis were conducted where appropriate. RESULTS: Hundred patients undergoing bulbar urethroplasty with VCUG prior to catheter removal were compared to 100 matched case controls without imaging. Groups did not differ with respect to failed endoscopic treatment (P = .82), prior urethroplasty (P = .09), comorbidities (P = .54), smoking (P = .42), or pre-operative bacteriuria (P = 1.00). The incidence of extravasation in the VCUG group was 2%. Overall 90-day complications were 9.5% and 15 patients developed recurrence with a median follow-up of 174 months. On chi-square analysis, 90-day complications did not differ between patients undergoing VCUG and those without (12% vs 7.0%; P = .34). On log-rank analysis, stricture recurrence did not differ between groups (P = .44). CONCLUSION: Routine imaging with VCUG after bulbar urethroplasty does not influence the risk of post-operative complications or stricture recurrence. Surgeons should consider avoiding this potentially unnecessary examination in routine clinical practice.

Diagnosis of traumatic urethral stricture in a canine patient with contrast-enhanced voiding urosonography : A case report.

A 5-year-old intact male mixed-breed dog presented with a 3-day history of stranguria and dysuria. Results of physical examination, plain radiographs, and ultrasonography were consistent with a traumatic urethral stricture in the prescrotal urethra just under the previous trauma region, resulting in partial obstruction of urine outflow. Contrast-enhanced voiding urosonography (CE-VUS) was performed, and a urethral stricture was confirmed. The dog underwent surgery. A scrotal urethrostomy was performed. After 3 days of hospitalization, the dog was discharged from the Clinic. Based on an extensive literature review, this is the first report using CE-VUS to evaluate urethral pathology in a canine patient.

An innovative method for occluding the urethral meatus and accessing urethra strictures in retrograde urethrography in males.

OBJECTIVES: To observe and evaluate the effectiveness and safety of using a sponge plug method to occlude the urethral meatus during retrograde urethrography (RUG) for accessing male urethral strictures. METHODS: 40 male patients with a mean age of 51.4 years and a history of urethral injury were primarily diagnosed with urethral stricture using a urethrocystoscope. RUG was performed using a ureteral catheter with a sponge plug inserted into the external meatus. Iodixanol, a contrast medium, was injected into the urethra or bladder for performing RUG and voiding cystourethrography (VCUG). The patients were positioned obliquely to obtain urethrograms. RESULTS: All X-ray radiologic procedures for performing urethrography were successful without any overflow of contrast liquid observed. In all cases, the sponge plugs became visible in the resulting images. The external meatuses were directly visualized in all cases on the obtained images, allowing identification of the number, location, and length of strictures as well as coexistent pathologies such as fistulas. In one case, the plug slipped off the meatus immediately after completing the procedure. The pain Visual Analogue Scale (VAS) was 0 to 2, mean 0.35. No instances of complication or adverse reactions was observed. CONCLUSIONS: The sponge plug effectively occludes the external urethral meatus for retrograde urethrography, enabling visualization of the actual caliber of the entire urethra, including the strictures and external meatus, by filling it with contrast liquid. This technique is safe and well-tolerated by patients.

Urethral Stricture Induction Followed by Buccal Mucosa Graft Urethroplasty in a Rat Model.

Urethral reconstruction is an important area of expertise for urologists. The buccal mucosa is considered the best option when urethral grafting is necessary, although in some cases, it is inappropriate or needs to be optimized to repair a given stricture. Therefore, developing innovative procedures and evaluating their putative success in experimental models is crucial to fit the clinical need. With this goal, this study describes a protocol in which urethral stricture was induced by electrocautery in Wistar rats. Urethral reconstruction was performed 1 week later with a buccal mucosa graft, harvested from the lower lip, and placed in a ventral onlay fashion. A retrograde urethrogram showed a significant improvement in urethral diameter after urethroplasty compared to the respective value after stricture induction. Additionally, the graft placement was assessed by blood perfusion analysis using laser Doppler. As expected, a dark blue area corresponded to the non-vascularized buccal mucosa graft. This procedure can successfully simulate the normal pathophysiological process of urethral injury and tissue modulation, as well as urethral reconstruction using a buccal mucosa graft in a reproducible manner, and serve as the basis for future research based on tissue engineering or urethral grafts.

Urethrocystography: a guide for urological surgery?

Urethrocystography remains the gold-standard technique for urethral pathology diagnosis. Nowadays, of the various indications for performing urethrocystography, the most common is due to a clinical suspicion of urethral stricture. Due to the high prevalence of strictures and their substantial impact on a patient's quality of life, the examination must allow the location, exclusion of multifocality, and assessment of the extent of the stricture to influence surgical planning. This article intends to demonstrate that the radiologist's role, by performing and interpreting the modality of urethrocystography, influences and is crucial for the urologic therapeutic decision and that the patients who were submitted to reconstruction by urethroplasty had a better success rate. The authors aim to review the radiological anatomy of the male urethra, discuss the modalities of choice for imaging the urethra (retrograde urethrography and voiding cystourethrography), provide an overview of the different indications for performing the study, examine the different etiologies for urethral strictures, understand the relevance of the different appearances of urethral pathology, and identify the surgical options, especially in the treatment of urethral strictures. Simultaneously, the study exposes cases of urethral trauma, fistulas, diverticulum, and congenital abnormalities.

Inter-rater reliability of retrograde urethrograms.

PURPOSE: Reliability of pre-operative testing is important for adequate surgical planning. For urethral stricture disease, preoperative planning frequently includes retrograde urethrogram (RUG). The radiographic interpretation of RUGs is often done by urologists themselves. We aimed to evaluate the reliability of RUG interpretation by urologists at our institution. METHODS: We examined the RUGs of 193 patients. These were deidentified and interpreted by three urologists, two general urologists and one reconstructive urologist. These interpretations were compared in 2 ways. Each of the general urologists was compared to the "gold standard" reconstructive urologist interpretation, and the general urologists were additionally compared to each other. We used intraclass correlation coefficient (ICC) for numerical variables and Fleiss' Kappa or Cohen's Kappa statistic (κ) for categorical variables to rate inter-interpreter reliability and agreement among interpretations with regards to the quantitative variables of stricture length and caliber. RESULTS: Level of agreement ranged from poor to moderate across all variables interpreted. Comparing general urologists to the gold standard yielded no better than moderate agreement, with the majority being poor to fair. Similarly, agreement amongst the general urologists did not reach above moderate, with the majority being poor to slight. CONCLUSION: To our knowledge, this is the first analysis of inter-rater reliability of RUGs among practicing urologists. Our analysis showed clinically unacceptable reliability with regards to stricture length, location, caliber, and indicated procedures. This study suggests a need for standardized interpretation of RUGs and poses an opportunity for actionable improvement in management of strictures.

Retrograde urethrography in children: a decade of experience at a children's hospital.

BACKGROUND: Retrograde urethrography (RUG) is a radiologic procedure that optimizes imaging evaluation of the urethra, particularly in settings of difficulty with micturition or urethral injury. OBJECTIVE: To review our experience with RUG at a large pediatric radiology practice. MATERIALS AND METHODS: We conducted a retrospective review of medical records and fluoroscopic images of RUGs performed from January 2010 to December 2020. RESULTS: We identified 180 RUG exams (median frequency 17 exams per year), all in male children (median age 13 years). The most common indications were stricture (42%; n=76), postsurgical evaluation (34%; n=62) and trauma (16%; n=29). The most commonly used catheter was Foley (40%; n=72), with a median catheter size of 5 French (Fr) for infants younger than 1 year, 7 Fr for children ages 1-5 years and 8 Fr for children older than 5 years. About a third of the children (57; 32%) had combined voiding cystourethrography (VCUG)-RUG exams. Water-soluble contrast agent, either 17% or 43% Cysto-Conray, was used. Most RUG exams were normal (46%; n=83). The most common urethral pathology was stricture (30%; n=54), commonly involving a bulbar urethra (n=26). Urethral trauma was seen in 11 children (6%), 10 bulbar and 1 membranous. Most children with stricture were surgically treated (n=40; 74%), whereas most children with trauma were conservatively treated (n=8; 73%). The remaining diagnoses included diverticula, polyps, valves, fistulas and duplications, constituting <17% of our sample; most of these were surgically treated. Four exams (2%) were non-diagnostic. RUG showed 89% sensitivity and 97% specificity compared to cystourethroscopy/VCUG findings. Technical difficulties occurred in 14 (8%) children (e.g., pain or inappropriate catheter seal). CONCLUSION: Our experience indicates that when catheterization techniques are properly tailored, RUG provides a useful and successful radiologic method of evaluating the pediatric male urethra.

Application of 3D printed pelvic fracture related urethra and surrounding tissue as preoperative planning model.

OBJECTIVE: Urethral stenosis caused by pelvic fracture urethral injury (PFUI) is a complex urological disease, especially for the redo cased. However, to find the proximal end of the posterior urethra, and to avoid injury to the rectum and to forecast to remove the inferior pubic margin are two key points for a successful surgery. These steps can be challenging for even the most experienced urologists. This study is to describe a new technique for understanding the three-dimensional (3D) anatomy of the urethra, which will also aid in surgical planning and simplify urethroplasty. MATERIALS AND METHODS: Three patients underwent routine urethroscopy, X ray urethrography and contrast CT urethrography. The 3D images were then reconstructed, and the data were transmitted to a 3D printer. 3D models were printed with polyacrylic acid to simulate the anatomical structure and relationship of urethral stenosis with pubic symphysis and rectum. Various diagnosis methods were compared with the condition in surgery. The patients and trainee questionnaires were performed. RESULTS: Three models of urethral CT were obtained. These models were presented to patients and trainee doctors along with routine urethroscopy, urethrography, and urethral CT. The scores of patients and trainee question forms demonstrated that the 3D printed urethral stenosis model of pelvic fracture has obvious advantages in urethral adjacency and ease of understanding. The 3D printed urethras were easy to show the pubic symphysis and simulate its excision and exposure of urethra. The model could show the precise distance from urethra to rectum to prevent the rectum injury in surgery. CONCLUSIONS: 3D printing technology can be applied to the preoperative evaluation of urethral stenosis caused by PFUI. It can be auxiliary to understand the anatomical structure of the posterior urethra, the direction of urethral displacement, protecting the rectum and the forecasting for pubectomy. It is especially helpful for the accurate preoperative planning of some complex urethral stenosis and redo cases.

3D CT Urethrography With Cinematic Rendering (3DUG): A New Modality for Evaluation of Complex Urethral Anatomy and Assessment of the Postoperative Phalloplasty Urethra.

OBJECTIVE: To develop an imaging modality for the postoperative phalloplasty urethra. Despite high urologic complication rates after masculinizing genital surgery, existing methods for postsurgical evaluation after phalloplasty have drawbacks. Fluoroscopic studies like the retrograde urethrogram have limitations like user-dependence and need for meticulous positioning but also are inadequate for the evaluation of the anatomically complex postphalloplasty urethra. We developed a novel protocol utilizing CT urethrography with 3D reconstruction using cinematic rendering (3DUG) for neo-urethral imaging. MATERIALS AND METHODS: Patients who underwent 3DUG after either phalloplasty, metoidioplasty, or prior to revision surgery were included. Low-dose imaging protocols were used to avoid any increases in radiation exposure. The first iteration of our protocol utilized retrograde contrast administration via the penile urethra, whereas the second iteration of our protocol utilized an antegrade technique with contrast instillation via the suprapubic catheter and a voiding scan. Imaging was initially obtained according to symptoms and then per protocol at 3 weeks after urethral lengthening. RESULTS: Twenty-six patients were included in the series. Among postoperative phalloplasty patients imaged for symptoms, contrast extravasation/fistula was identified in 5 (63%), vaginal remnant in 3 (38%), and stricture in 2 (25%) compared to 5 (45%), 1 (9%), and zero respectively for patients imaged routinely. When intervention was required, operative findings correlated to anatomy on imaging. CONCLUSION: We present a new protocol for the use of 3D CT urethrography with cinematic rendering for neo-urethral reconstruction. This technique has the potential to improve surgical planning and surveillance of urologic complications in postphalloplasty patients.

Imaging in urethral stricture disease: an educational review of current techniques with a focus on MRI.

Urethral stricture disease refers to narrowing of the urethral lumen obstructing the flow of urine. Urethral strictures can significantly impact daily life due to incontinence, incomplete emptying, hesitancy, and increased risk of urinary tract infections. Imaging is central to the evaluation of suspected urethral stricture, as assessment of stricture length and severity is crucial for guidance of surgical management. The currently employed modalities include radiography, chiefly retrograde urethrography (RUG) and voiding cystourethrography (VCUG); magnetic resonance urethrography (MRU); and sonourethrography (SUG). MRU has become a recent focus of research as it provides high spatial resolution, multiplanar capacity, and soft tissue type differentiation for evaluation of periurethral compartments and concurrent soft tissue defects. The protocol for MRU has evolved over the years to now include dynamic micturition imaging and image reconstruction options. In this review, we discuss each of the imaging modalities used in the diagnosis and evaluation of urethral stricture and provide an overview of literature on MRU over the last decade, including suggested indications that have not yet been incorporated into current guidelines. We delineate scenarios where special diagnostic imaging beyond radiography is beneficial, providing examples from our practice and description of our techniques for each modality.

Identifying urethral strictures using machine learning: a proof-of-concept evaluation of convolutional neural network model.

INTRODUCTION: To evaluate urethral strictures and to determine appropriate surgical reconstructive options, retrograde urethrograms (RUG) are used. Herein, we develop a convolutional neural network (CNN)-based machine learning algorithm to characterize RUG images between those with urethral strictures and those without urethral strictures. METHODS: Following approval from institutional REB from participating institutions (The Hospital for Sick Children [Toronto, Canada], St. Luke's Medical Centre [Quezon City, Philippines], East Virginia Medical School [Norfolk, United States of America]), retrograde urethrogram images were collected and anonymized. Additional RUG images were downloaded online using web scraping method through Selenium and Python 3.8.2. A CNN with three convolutional layers and three pooling layers were built (Fig. 1). Data augmentation was applied with zoom, contrast, horizontal flip, and translation. The data were split into 90% training and 10% testing set. The model was trained with one hundred epochs. RESULTS: A total of 242 RUG images were identified. 196 were identified as strictures and 46 as normal. Following training, our model achieved accuracy of up to 92.2% with its training data set in characterizing RUG images to stricture and normal images. The validation accuracy using our testing set images showed that it was able to characterize 88.5% of the images correctly. CONCLUSION: It is feasible to use a machine learning algorithm to accurately differentiate between a stricture and normal RUG. Further development of the model with additional RUGs may allow characterization of stricture location and length to suggest optimal operative approach for repair.

Missed urethral duplication associated with hypospadias, post-hypospadias repair urethral stenosis, and recurrent urinary tract infections in an adult: a case report.

BACKGROUND: Duplication of urethra is a very rare congenital disorder. Several types of this anomaly have been reported around the world, and are also discussed in this report. However, the mechanism of this anomaly is still unclear. CASE: A 45-year-old Persian man with a complaint of recurrent urinary tract infection was referred to our clinic. He had a history of repairing penoscrotal hypospadias in childhood along with obstructive and irritating symptoms in adolescence. On his last voiding cystourethrogram and retrograde urethrogram, stenosis was observed in the proximal bulbar urethra along with a double urethra in the dorsal region of the main urethra. The double urethra was removed with operation, and he was followed for 1 month after surgery. He had no complaints of recurrence or urinary incontinence. CONCLUSIONS: This report shows the different classification systems, types of double urethra, and approach and management, which mainly involves surgery; however, surgical management should be done according to the anatomical findings of the abnormality.

A multimodality review of male urethral imaging: pearls and pitfalls with an update on urethral stricture treatment.

Optimum radiological assessment of the male urethra requires knowledge of the normal urethral anatomy and ideal imaging techniques based on the specific clinical scenario. Retrograde urethrography is the workhorse examination for male urethral imaging, usually utilized as the initial, and often solitary, modality of choice not only in the setting of trauma, but also in the pre- and post-operative evaluation of urethral strictures. There is, however, growing interest in utilization of ultrasound and magnetic resonance for evaluation of the male urethra owing to lack of ionizing radiation and improved delineation of the adjacent tissue. We review the various modalities utilized for imaging of the male urethra for a variety of known or suspected disorders, and provide an update on current treatments of urethral strictures. Additionally, we detail the key information needed by urologists to guide management of urethral strictures. We conclude with a brief discussion of neophallus urethral diseases following female-to-male sexual confirmation surgery.