Abstract
Background:
Urethrography is a radiologic procedure that optimizes imaging evaluation of the urethra, particularly in settings of difficulty with micturition or urethral injury. Urethrography remains the gold standard imaging tool, providing reliable and accurate diagnosis and staging of urethral stricture disease.
Materials and Methods:
A 10-year review of patients’ archive who had retrograde urethrography or combined urethrography examinations in a peripheral facility from January 2014 to December 2023 was carried out. A total of 247 patients with complete records who met the inclusion criteria were included in this study. Demographic data, clinical indications, and the imaging findings were documented. The data were collated, entered into a computer, and processed by the use of Statistical Package for Social Sciences (SPSS), version 23, to determine frequencies (means ± standard deviations). The results are presented using frequency tables and percentages as appropriate. A P value of <0.05 was considered statistically significant with a confidence interval of 95%.
Results:
The examination was normal in 89 (36.0%) patients. Urethral stricture was the commonest abnormality (44.5%) and commonly affects the bulbar urethra (70.9%). About 83.6% of the patients with stricture had 1–2 strictures while 16.4% had multiple urethral strictures. About 63.6% of patients with urethral strictures had short segment stricture, which was common at the bulbar urethra.
Conclusion:
Urethrography is an effective and cheap means of imaging the urethra mostly indicated on account of strictures and lower urinary tract symptoms. The urethral stricture is the commonest abnormal finding, which commonly affects the bulbar urethra.
Keywords: Post prostatectomy, retrograde urethrogram, stricture, urethra, urethroplasty
Introduction
The urethra has the dual purpose of being a conduit for urine and semen, both functions of which are sine qua non for a good-quality life.
Lower urinary tract symptoms comprise a number of symptoms which originate from the urinary bladder, they include but are not limited to: frequency, urgency, nocturia, slow or intermittent stream, feeling of incomplete emptying and terminal dribbling. Urethral stricture is one of the most significant causes of lower urinary tract symptoms which constitutes a large proportion of the urologist’s workload and in turn warrants frequent radiological investigation by the radiologist. Urethral stricture is a common condition, which results in 1.5 million clinic visits over a 9-year period (from 1992 to 2000) and approximately 5000 inpatient visits in 2000 in the United States with enormous financial burden for treatment of about $191 million in health care expenditures.[1]
Most patients present with many symptoms with obstructive lower urinary tract symptoms being the most common.[2] Furthermore, numerous sequelae such as bladder calculi, recurrent infection, fistula, and chronic renal insufficiency can result from untreated urethral stricture disease and significantly affect patient quality of life.[2]
In the 1960s, gonococcal urethritis was the most common cause of urethral stricture until effective antibiotic became available. Currently, the causes of urethral stricture include trauma, instrumentation, catheterization, transurethral resection of prostate, open prostatectomy, post hypospadias repair, lichen sclerosis, and urethritis.[3]
The male urethra is divided into two portions: the posterior urethra, consisting of the prostatic and membranous urethra, and the anterior urethra, consisting of the bulbous and penile urethra, and this subdivision is important for clinical reasons and related to the treatment of urethral disease. The external urethra sphincter, located in the urogenital membrane, demarcates the posterior urethra from the anterior urethra. The posterior urethra has smooth muscle that relaxes when the detrusor muscle contracts during voiding, which is best seen on voiding cystourethrography.
Retrograde urethrography (RUG) is a medical imaging procedure used to visualize the urethra and diagnose abnormalities involving the urethra while Micturating cystourethrography (MCUG) is a diagnostic imaging procedure that utilizes x-rays to visualize the bladder and urethra during voiding. A retrograde study is the most appropriate way to evaluate the anterior part of the urethra while voiding study is the appropriate way of evaluating the posterior urethra; therefore, “dynamic” urethrography represents a synergy of these two imaging techniques.[4]
The indications for retrograde urethrography and voiding cystourethrography include but not limited to urethral strictures, trauma, lower urinary tract structural abnormalities, urethral masses, urethral diverticulum, or urethral fistula and postoperative evaluation.[5]
Urethral imaging is therefore a critical step in preoperative patient evaluation before definitive surgical management. Urethrography remains the gold standard imaging tool, providing reliable and accurate diagnosis and staging of urethral stricture disease. Combination of RUG with other imaging modalities can improve and facilitate diagnosis in complex situations. Voiding cystourethrography can provide insight to the degree of functional impairment of the bladder neck and urethra and can provide critical staging information in combination with RUG in complex pelvic fracture-associated urethral injuries.[6]
Conventional imaging of the urethra with a dynamic retrograde urethrocystography is a cost-effective, easy-to-perform, readily available, and reproducible examination that can detect clinically relevant strictures involving the anterior urethra and those with extension into the membranous urethra, making it still the initial imaging of choice for suspected stricture disease in the developing countries such as Nigeria.[7]
Other modalities employed in the evaluation of lower urinary tract include sonourethrography, magnetic resonance urethrography, and urethrocystoscopy. Sonourethrography can be used as adjunct to RUG; however, when used singly, it is limited by only evaluation of the proximal bulbar urethra while magnetic resonance urethrography has limited availability especially in resource-limited countries as its main drawback.[8,9]
Materials and Methods
A 10-year review of the records of 324 patients who had retrograde urethrography and/or combined urethrography examinations for various indications in a peripheral facility from January 2014 to December 2023 was carried out. Patients with incomplete documentation were excluded from the study leaving 247 patients with complete records.
The indication for the examination of each patient was documented. Each image was reviewed, interpreted, and placed in a diagnostic categories, including but not limited to urethral stricture, urethrocutaneous fistula, urethral diverticulum, and prostatic enlargement.
The examination was performed using a multix swing floor mount 500MAs X-ray machine (Siemens, 2007 Germany) fitted with a stationary grid. Demographic data were obtained including clinical indications and cystourethrography findings. The data were collated, entered into a computer, and processed by the use of Statistical Package for Social Sciences (SPSS), version 23, to determine frequencies (means ± standard deviations). The results are presented using frequency tables and percentages as appropriate. A P value of <0.05 was considered statistically significant with a confidence interval of 95%.
Approval for the study was granted by the hospital research and ethics board, and the informed consent was obtained from all the patients.
Results
The findings were considered significant if they were diagnostic for a particular disease process or if they were suspicious enough to warrant further clinical examination. Interpretations were made by a consultant radiologist with over 10 years of practice experience and expertise.
Patients’ Demography
A total of 324 patients’ images were reviewed, but only 247 with complete documentation who met the inclusion criteria were enrolled for the study, with a prevalence of 76.2%. All the patients were incidentally men with a mean age of 52.15 ± 16.99 years [Table 1]. Most of the patients evaluated were in the age group of 40–59 years (40.5%).
Table 1.
Age group, indications, and findings of patients
| Indications | Age group (years) | Total (%) | ||||
|---|---|---|---|---|---|---|
| 0–19 | 20–39 | 40–59 | 60–79 | 80–99 | ||
| Bladder outlet obstruction | 0 | 0 | 2 | 6 | 2 | 10 (4.0) |
| LUTS | 4 | 4 | 22 | 25 | 1 | 56(22.7) |
| Post prostatectomy | 0 | 0 | 0 | 5 | 1 | 6 (2.4) |
| Post urethroplasty | 1 | 7 | 11 | 12 | 0 | 31 (12.6) |
| Rectourethral fistula | 0 | 1 | 0 | 0 | 0 | 1 (0.4) |
| Rectovesical fistula | 0 | 0 | 0 | 1 | 0 | 1 (0.4) |
| Post rectovesical fistula repair | 0 | 0 | 0 | 1 | 0 | 1 (0.4) |
| Stricture | 1 | 24 | 61 | 37 | 2 | 125 (50.6) |
| Trauma | 1 | 8 | 3 | 2 | 0 | 14 (5.7) |
| Urethrocutanous fistula | 1 | 0 | 1 | 0 | 0 | 2 (0.8) |
| Total (%) | 9 (3.6) | 44 (17.8) | 100 (40.5) | 88 (35.6) | 6 (2.4) | 247 (100.0) |
| Findings | ||||||
| Normal | 5 | 18 | 41 | 25 | 0 | 89 (36.0) |
| Anastomotic leak | 0 | 0 | 1 | 3 | 0 | 4 (1.6) |
| Bladder calculus | 0 | 0 | 1 | 0 | 0 | 1 (0.4) |
| Bladder diverticulum | 0 | 0 | 0 | 2 | 1 | 3 (1.2) |
| BPH | 0 | 0 | 7 | 11 | 1 | 19 (7.7) |
| Meatal stenosis | 1 | 0 | 1 | 3 | 0 | 5 (2.0) |
| Rectovesical fistula | 0 | 0 | 0 | 1 | 0 | 1 (0.4) |
| Urethral Stricture | 0 | 25 | 42 | 39 | 4 | 110 (44.5) |
| Urethral diverticulum | 1 | 0 | 0 | 2 | 0 | 3 (1.2) |
| Urethral stone | 0 | 0 | 2 | 0 | 0 | 2 (0.8) |
| Urethrorectal fistula | 0 | 1 | 0 | 0 | 0 | 1 (0.4) |
| Urethrocutanous fistula | 2 | 0 | 5 | 2 | 0 | 9 (3.6) |
| Total | 9 | 44 | 100 | 88 | 6 | 247 (100.0) |
Mean age: 52.15 ± 16.99 years
Indication for the examination
The indications for the examination were mostly on account of stricture in over half (50.6%) of the patients, lower urinary tract symptoms in 56 (22.7%) patients, and check post urethroplasty in 31 (12.6%) of the patients [Table 1].
Examination findings
The examination was normal in 89 (36.0%) patients and abnormal in 158 (64.0%) patients. The common abnormal finding was urethral stricture (44.5%) and followed distantly by prostatic hypertrophy (7.7%). Other findings include urethrocutaneous fistula constituting 3.6%, meatal stenosis (2.0%), anastomotic leak post urethroplasty (1.6%), urethral diverticulum (1.2%), urethral stone (0.8%) and bladder diverticulum (1.2%). The least findings were urethrorectal fistula and vesicorectal fistula constituting 0.4% each [Table 1].
The age group 40–59 and 60–79 years had the majority of the abnormal findings constituting 37.3% and 39.9%, respectively. Similarly, the same age groups had the majority of normal findings constituting 46.1% and 28.1%, respectively. The least findings were seen in age groups 0–19 years constituting 2.5% and 5.6% for abnormal and normal, respectively. This was statistically significant [Table 2, P < 0.005].
Table 2.
Relationship between urethral findings and age groups
| Age group | ||||||
|---|---|---|---|---|---|---|
| Findings | 0–19 | 20–39 | 40–59 | 60–79 | 80–99 | Total |
| Normal findings | 5 (5.6) | 18 (20.2) | 41 (46.1) | 25 (28.1) | 0 (0.0) | 89 (100.0) |
| Abnormal findings | 4 (2.5) | 26 (16.5) | 59 (37.3) | 63 (39.9) | 6 (3.8) | 158 (100.0) |
| Total | 9 | 44 | 100 | 88 | 6 | 247 |
χ2 = 10.577 (df = 4); P = 0.032
Urethral strictures affect the bulbar urethra in 78 (70.9%) patients followed distantly by the membranous and penile urethra in 12 (10.9%) and 18 (16.4%) patients, respectively. Most (83.6%) of the patients with urethral stricture disease had 1–2 strictures while the few (16.3%) had multiple urethral strictures [Table 3]. Almost two-third (63.6%) of patients with urethral strictures had short segment stricture while 30 (27.3%) patients had medium segment stricture with about a tenth of the patients having long segment (≥5 cm) urethral stricture. Short and medium length strictures were common at the bulbar urethra [Table 4].
Table 3.
Site of stricture and number of strictures
| Site of strictures | Number of strictures | Total (%) | |
|---|---|---|---|
| 1–2 | ≥3 | ||
| Bulbar | 63 | 15 | 78 (70.9) |
| Membranous | 12 | 0 | 12 (10.9) |
| Penile | 15 | 3 | 18 (16.4) |
| Prostatic | 2 | 0 | 2 (1.8) |
| Total (%) | 92 (83.6%) | 18 (16.4%) | 110 (100.0) |
Table 4.
Site of stricture and length of strictures
| Site of strictures | Length of strictures | Total | ||
|---|---|---|---|---|
| Short segment (1–2 cm) | Medium segment (3–4 cm) | Long segment (≥5cm) |
||
| Bulbar | 52 | 23 | 3 | 78 |
| Membranous | 7 | 4 | 1 | 12 |
| Penile | 11 | 3 | 4 | 18 |
| Prostatic | 0 | 0 | 2 | 2 |
| Total (%) | 70 (63.6%) | 30 (27.3%) | 10 (9.1%) | 110 |
Discussion
Retrograde urethrography and voiding cystourethrography are two indispensable radiologic investigations frequently employed in urologic assessment of the lower urinary tract. These procedures can be used in combination or independent of each other and provide very useful diagnostic information, which is usually critical in management. A wide range of indications warrant request for RUG and/or MCUG with a corresponding wide range of possible findings.[10]
The mean age of the study population was 52.15 ± 16.99 years with most of the patients being in the age group 40–59 years (40.5%). Mbaba et al.[11] documented a similar mean age of 52.75 ± 4.79 years with majority of the respondents being in the age group 50–59 years. Kiridi et al.[12] also documented a mean age of 51.44 ± 17.67 years. However, this is at variance with the mean age of 43.40 ± 18.50 years and 43.1 years as documented by Ahidjo et al.[7] and Tijanni et al.[13] in Maiduguri and Lagos, Nigeria, respectively.
The etiology of urethral stricture varies with study population. The main etiologies of urethral strictures are idiopathic, iatrogenic, inflammatory, traumatic, and tumoral. Iatrogenic and inflammatory strictures are responsible for most strictures in low- and medium-income countries (LMIC).[14] Urethrography was carried out on account of urethral stricture disease in 50.6% of patients in this study. This is in agreement with the findings of Elsingergy et al.[15] who documented urethral stricture as the most common indication in 42.0%. However, it is at variance with the findings of some authors who documented trauma as a common indication for cystourethrography.[16] Tijanni et al.[13] in Lagos, Nigeria, concluded that trauma is now undisputed cause of urethral stricture disease accounting for 72.3% of patients. Similarly, Ekeke and Amusan[17] in Port Harcourt, Nigeria, documented trauma as the cause of stricture accounting for 74.22%. This finding is at variance with the previously known fact that inflammatory and iatrogenic etiologies were the common cause of urethral stricture disease in LMIC. This could be due to the cosmopolitan nature of both cities, wide-scale promotion of safe sexual practices and timely treatment with antimicrobials with considerable reduction in inflammatory and iatrogenic strictures. Only 5.7% patients were evaluated on account of trauma in this study. Postsurgical evaluation was indicated in 15.8% of patients.
Pericatheter urethrography is a useful radiological diagnostic method for evaluation of the appropriate time of catheter removal after urethroplasty. It helps assess urethral healing and patency after urethroplasty. In addition to fistula formation, contrast extravasation is a common finding in postsurgical evaluation of the urethra. Anastomotic leak (extravasation) was seen in four patients (1.6%), which usually informs the urologist on when the urethral catheter should be removed.
The common abnormal finding in this study was urethral stricture seen in 44.5% of the patients. Urethral stricture disease is a relatively common disease in older men. Santucci et al.[1] analyzed urethral stricture disease in 10 private data sets in the United States and concluded that urethral stricture disease is common in the elderly population with marked increase after 55 years of age. This is in agreement with findings in this study, which shows that 77.3% of patients with urethral stricture disease were ≥40 years. Short segment strictures was more prevalent (63.6%). The bulbar urethra (70.9%) was most affected while anterior urethral stricture constitutes 81.8%. This is in agreement with the study of Mbaba et al.[11] in Port Harcourt, Nigeria, as well as Ekeke and Amusan[17] where 76.25% and 42.27% of the total cases evaluated had anterior urethral stricture, respectively. In addition, Ahidjo et al.[7] reported 96.9% cases of anterior urethral stricture in their study in Maiduguri, North Eastern Nigeria. Anterior urethral strictures involving the bulbar region of the urethra have been attributed to the inferior position of the urethra relative to the pubis predisposing it to astride crush injury following a fall.[18]
Multiple strictures affecting mostly the bulbar urethra accounted for 16.4% in this study while solitary or two strictures account for the remaining 83.6%. This was at variance with findings 68.75% for multiple strictures and 31.25% for single stricture documented by Mbaba et al.[11]
Long segment stricture accounted for 9.1% in this study. This is in agreement with the finding of 14.43% and 16.0% patients documented by Ekeke and Amusan[17] and Kiridi et al.[12]
The demographic variations observed with urethral stricture disease in this study showed majority of the urethral stricture cases were within the age group of 40–79 years, which is in keeping with the findings by Mbaba et al. in Port Hacourt[11] and Olajide et al. in Oshogbo.[19] Therefore, accurate diagnosis is vital for a successful management outcome in such patients. This is especially important in that urethral stricture has remained a major challenge to the urologist till date.[20]
Urethrogram demonstrating an opacified tract extending from the urethra to a communicating organ or skin are in keeping with fistula formation. Urethrocutaneous fistula shows contrast extending to the skin surface and accounts for 3.6% of the findings in this study. This commonly occurs as a postoperative complication of urethral repair, and the finding is consistent with the findings of Abubakar et al.[21] who reported 4.1% urethrocutaneous fistula as postoperative complication of urethral stricture disease repair on urethrography in North East Nigeria.
Eighty-nine patients (36%) evaluated during this study had normal finding, which rules out the presence of morphologic or anatomic abnormality. Such patients will also benefit from laboratory work-up.
Limitations
The retrospective review of the records without inputs from further clinical reviews and intraoperative findings may affect this study.
Recommendation
A prospective study in multiple centers for the evaluation of cystourethrographic findings in patients with lower urinary tract symptoms is required.
Conclusion
Urethrography is an effective, cheap, and complementary imaging tool in evaluating the urethra. It was requested mostly on account of strictures, lower urinary tract symptoms, and check post urethroplasty. Urethral stricture was the commonest abnormal finding and commonly affects the bulbar urethra.
Conflicts of interest
None.
Authors contributions
IEO: Conceptualization and writing original draft. GEA: Methodology. IKO: Data analysis. AD: Writing Original draft. SAJ: Review and editing. TYF: Visualization (figures and tables). DSM: Review and editing. AD: Writing original draft/Review. PSD: Supervision (Oversight and mentorship). IU: Figures and tables and editing.
Ethical policy and Institutional Review board statement
This study was conducted in accordance with the ethical principles outlined in the Helsinki declaration. The research protocol was approved by the JUTH Health Research Ethics Committee Board (approval Ref: JUTH/DCS/IREC/127/XXXI/2658, date: 18th March, 2024). Informed consent was obtained from participants prior to their enrolment in the study. The confidentiality and anonymity of participants were ensured throughout the research process.
Patient declaration of consent
I hereby declare that I have been fully informed about the research study titled “Retrograde urethrography and voiding cystourethrography: Indications and findings in patients presenting with lower urinary tract symptoms in Jos, North Central Nigeria”. I understand purpose of the study and am aware of the potential risks and discomforts. I have been told that I can withdraw my consent at any time. I voluntarily consent to participate in this study and understand that my confidentiality and anonymity will be maintained.
Data availability statement
The data that support the findings of this study is available on request from the corresponding author (IEO)
Acknowledgement
The authors sincerely recognize and express profound gratitude for the contributions of our colleagues/collaborators who provided valuable insights and assistance during the research. We also thank the participants who volunteered for this study, support staff and article review assistance which help to make this research and publication possible.
Funding Statement
Nil.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Data Availability Statement
The data that support the findings of this study is available on request from the corresponding author (IEO)