Hypothesis / aims of study
The aim of this case series was to evaluate the effectiveness of Magnetic Resonance Imaging (MRI) in diagnosing and managing non-traumatic obliterative urethral strictures, particularly in complex cases where traditional methods such as retrograde urethrography (RUG) may be limited. This study emphasizes the utility of MRI in visualizing the urethral lumen and surrounding tissues, aiding in the preoperative assessment and guiding surgical interventions. MRI’s potential for providing detailed anatomical information, particularly in evaluating periurethral tissues and spongiofibrosis, is highlighted as a key factor for improving surgical outcomes and patient management.
Study design, materials and methods
The case series involved three male patients, aged 58 to 63 years, who had non-traumatic obliterative urethral strictures and were managed using MRI for preoperative evaluation. MRI was performed according to the “Joshi protocol,” which involves the use of an alpha-blocker to ensure adequate bladder neck opening, followed by sterile saline injection through a cystostomy (if present) and lignocaine gel for urethral administration. This technique has been shown to provide more accurate depictions of the urethral gap compared to conventional urethrography. All patients gave informed consent for their data to be used. MRI sequences included T2-weighted and post-contrast T1-weighted images to assess the urethral and periurethral anatomy, including spongiofibrosis and fibrosis-related changes.
Results
Three cases were presented, each demonstrating a distinct management approach:
1. Case 1: A 62-year-old male with recurrent urethral strictures after-coronary bypass surgery and internal urethrotomy. MRI revealed complete occlusion of the distal prostatic urethra and partial stenosis in the proximal bulbous urethra. Anastomotic urethroplasty was successfully performed, excising a 2 cm fibrotic segment.
2. Case 2: A 63-year-old male post-liver transplant with a recurrent obliterative urethral stricture. MRI and retrograde urethrography confirmed a 2.5 cm stricture in the bulbous urethra, leading to an end-to-end anastomotic urethroplasty after excision of the stricture.
3. Case 3: A 58-year-old male with a complex stricture, thought to be post-traumatic, was diagnosed with a non-traumatic obliterative stricture. MRI identified a 7 mm stenotic segment in the distal penile urethra. Urethroplasty was performed, addressing the complex stricture with an appropriate surgical approach.
Each case illustrated the ability of MRI to provide critical preoperative information, enabling more precise surgical planning and a tailored approach for each patient.
Interpretation of results
The results emphasize the role of MRI in providing detailed and reliable anatomical information for complex non-traumatic obliterative urethral strictures. In each case, MRI effectively identified the location, length, and extent of the strictures, which were critical in planning the surgical approach. MRI was particularly useful in detecting fibrosis and soft tissue involvement that might not have been fully visible with traditional methods like retrograde urethrography. Moreover, MRI was essential in guiding surgeons to perform appropriate urethroplasty techniques, such as end-to-end anastomotic repairs, thus improving surgical outcomes.
MRI also demonstrated its superior soft tissue resolution compared to other imaging methods, highlighting its potential for better evaluating spongiofibrosis and periurethral tissues, which are cruical in urethral stricture management. The ability to assess the urethra without radiation exposure was another significant advantage, especially in patients requiring multiple imaging studies.