# Urethral Stricture Disease in Males

## Introduction

Urethral stricture disease in males is characterized by the narrowing of the urethral lumen due to spongiofibrosis, which is scarring of the corpus spongiosum surrounding the urethra. The term "stricture" specifically refers to narrowing in the anterior urethra, which includes the bulbar and penile segments lined by spongy epithelium. Narrowing of the posterior urethra, which comprises the membranous and prostatic segments, is more accurately described as a "stenosis" or "contracture." This condition affects approximately 0.6% of the male population and is associated with significant morbidity, including voiding dysfunction, urinary retention, and recurrent urinary tract infections.

## Anatomy

The male urethra can be divided into several segments, each with distinct anatomical and clinical relevance. The fossa navicularis extends from the distal meatus to the junction between squamous and transitional epithelium and is surrounded by glans tissue rather than spongiosum. The penile or pendulous urethra runs from the fossa navicularis to the penoscrotal junction and is enveloped by a thin layer of corpus spongiosum. The bulbar urethra spans from the penoscrotal junction to the membranous urethra and is surrounded by a thick corpus spongiosum with a robust blood supply; this segment is the most common site for strictures. The membranous urethra passes through the urogenital diaphragm and is encircled by the external urethral sphincter; it is typically involved in pelvic fracture urethral injuries (PFUI). Lastly, the prostatic urethra traverses the prostate gland, where strictures are often referred to as bladder neck contractures, especially following transurethral resection of the prostate (TURP), or posterior urethral stenosis.

## Etiology

The causes of urethral stricture disease are varied. Idiopathic strictures account for 33-45% of cases, particularly in developed countries, and are most commonly seen in the bulbar urethra. These are thought to result from unrecognized minor trauma or inflammatory conditions such as lichen sclerosus. Iatrogenic causes comprise 30-40% of strictures and include traumatic catheterization or prolonged indwelling catheters, transurethral procedures like TURP, cystoscopy, and ureteroscopy, as well as hypospadias repair, which is the most common cause in pediatric patients. Radical prostatectomy can lead to vesicourethral anastomotic stenosis in 8-10% of cases, while radiation therapy for prostate cancer—either external beam or brachytherapy—produces obliterative, ischemic strictures with poor tissue quality. Traumatic strictures, accounting for 15-20%, commonly arise from straddle injuries where the bulbar urethra is crushed against the pubic symphysis, or from pelvic fracture urethral injuries involving the membranous urethra, which occur in 5-10% of pelvic fractures. Infectious causes, once dominated by gonorrheal urethritis, are now uncommon in developed nations. Lichen sclerosus, also known as balanitis xerotica obliterans (BXO), is a chronic inflammatory dermatosis that causes progressive meatal and penile urethral strictures, often presenting with whitish plaques on the glans and foreskin and potentially involving the entire urethra (panurethral involvement).

<image>Sagittal anatomic diagram of the male urethra showing the four segments (prostatic, membranous, bulbar, penile, fossa navicularis) with the most common stricture locations highlighted, typical etiologies labeled at each site (iatrogenic at prostatic, PFUI at membranous, idiopathic/straddle at bulbar, lichen sclerosus at penile/meatal), and the surrounding corpus spongiosum depicted at varying thickness</image>

## Clinical Presentation and Diagnosis

Patients with urethral stricture disease typically present with obstructive lower urinary tract symptoms (LUTS), including decreased force of the urinary stream, straining to void, a sensation of incomplete bladder emptying, and prolonged voiding times. Acute or chronic urinary retention may also occur. Recurrent urinary tract infections and epididymitis are common complications. Patients may report urethral discharge, post-void dribbling, or notice spraying or splitting of the urinary stream.

Diagnostic evaluation begins with imaging studies. The retrograde urethrogram (RUG) is the gold standard for assessing anterior urethral strictures, as it delineates the location, length, and severity of the narrowing. The voiding cystourethrogram (VCUG) evaluates the posterior urethra during voiding and is essential in cases of pelvic fracture urethral injury. Combining RUG and VCUG provides the most comprehensive assessment, especially for posterior urethral disruptions, by demonstrating the length of any gap. Uroflowmetry is a useful noninvasive test; a maximum flow rate (Qmax) below 15 mL/s with a plateau-shaped flow curve suggests a stricture. Cystourethroscopy allows direct visualization of the urethral lumen, enabling precise assessment of stricture caliber and location, and complements radiographic studies. Ultrasound, specifically sonourethrography with saline retrograde instillation, is an emerging modality that can assess the depth and length of spongiofibrosis.

## Management

### Endoscopic Therapies (Palliative)

Endoscopic treatments serve primarily as temporizing or palliative measures. Urethral dilation involves the sequential passage of dilators such as Amplatz, filiform and followers, or balloon dilators. This approach is a temporary measure, with recurrence rates of 50-60% at one year for bulbar strictures. Direct vision internal urethrotomy (DVIU) entails a cold-knife incision of the stricture at the 12 o’clock position under direct visualization. It yields the best outcomes for short strictures less than 1-2 cm in length, single in number, located in the bulbar urethra, and without prior interventions. The initial success rate for DVIU is approximately 50-60%, but this drops to 20-30% for subsequent attempts. Repeated DVIUs are discouraged because each procedure exacerbates spongiofibrosis, lengthens the stricture, and diminishes the success of future urethroplasty. After DVIU, intermittent clean self-catheterization may be employed to maintain urethral patency, which can delay but usually does not prevent recurrence.

### Urethroplasty (Definitive)

Definitive management of urethral strictures is achieved through urethroplasty. Excision and primary anastomosis (EPA) is considered the gold standard for short bulbar strictures less than 2-3 cm. This technique involves complete excision of the fibrotic segment followed by a tension-free, spatulated, end-to-end anastomosis. Long-term success rates range from 90-95%. However, EPA carries risks such as chordee (penile curvature) and penile shortening if applied to longer strictures or those in the penile urethra, making it contraindicated in these settings.

Augmentation urethroplasty uses grafts or flaps to reconstruct the urethra. The buccal mucosa graft (BMG), harvested from the inner cheek, is the current graft of choice due to its thick epithelium, thin lamina propria, rich vascular supply, resistance to infection, and ease of harvest. The dorsal onlay technique, known as the Barbagli technique, places the graft on the dorsal surface of the urethra, supported by the tunica albuginea of the corporal bodies, and is preferred for bulbar strictures. The ventral onlay graft is placed ventrally and is technically simpler but used selectively. The dorsal inlay technique, or Asopa technique, involves a dorsal urethrotomy with the graft inlaid into the opened dorsal urethral wall. Penile skin flaps, such as the Orandi flap, are pedicled fasciocutaneous flaps used primarily for penile urethral strictures but are more complex and have higher complication rates than grafts. Augmentation urethroplasty achieves success rates of 85-90% at long-term follow-up.

Staged urethroplasty is indicated for panurethral strictures, lichen sclerosus, failed prior repairs, or poor tissue quality. The first stage involves opening the stricture ventrally and placing a buccal mucosa graft as an inlay, marsupializing the urethral plate to create a neourethral surface. The patient voids through a perineal urethrostomy or hypospadiac meatus during this interval. The second stage, performed 6-12 months later, tubularizes the neourethral plate over a catheter. The Johanson technique is a staged repair commonly used for complex penile strictures.

Posterior urethroplasty for pelvic fracture urethral injury (PFUI) is best performed as a delayed primary repair, waiting approximately three months for resolution of the pelvic hematoma. The perineal approach involves excision of fibrosis, mobilization of the bulbar urethra, and spatulated anastomosis to the prostatic apex. Various maneuvers such as corporal splitting, inferior pubectomy, and supracrural rerouting may be employed to bridge the gap. Success rates range from 85-95% in experienced hands.

<image>Surgical illustration showing dorsal onlay buccal mucosa graft urethroplasty for a bulbar urethral stricture: (1) perineal incision with bulbar urethra exposed, (2) dorsal urethrotomy through the stricture, (3) buccal mucosa graft sutured to the tunica albuginea of the corpora cavernosa with the dorsal urethral edges sutured to graft margins, and (4) completed repair with urethra closed over a catheter</image>

| Technique | Indication | Success Rate | Key Details |
|---|---|---|---|
| DVIU / Dilation | Short (<1-2 cm) bulbar stricture; first attempt | 50-60% (first); 20-30% (repeat) | Palliative; repeated attempts worsen stricture |
| Excision and Primary Anastomosis (EPA) | Short (<2-3 cm) bulbar stricture | 90-95% | Gold standard for short bulbar; contraindicated in penile urethra |
| Dorsal onlay BMG (Barbagli) | Longer bulbar strictures (>2 cm) | 85-90% | Graft supported by tunica albuginea; preferred for bulbar |
| Ventral onlay BMG | Selected bulbar/penile strictures | 85-90% | Technically simpler; selective use |
| Dorsal inlay BMG (Asopa) | Bulbar strictures | 85-90% | Dorsal urethrotomy with graft inlaid |
| Penile skin flap (Orandi) | Penile urethral strictures | 80-85% | Pedicled fasciocutaneous flap; higher complication rate |
| Staged urethroplasty (Johanson) | Panurethral, lichen sclerosus, failed repairs | 80-90% | Two stages 6-12 months apart; uses BMG |
| Posterior urethroplasty | Pelvic fracture urethral injury | 85-95% | Delayed 3 months; perineal approach |

### Special Situations

Lichen sclerosus requires avoidance of genital skin for reconstruction because diseased skin will lead to recurrence. Buccal mucosa grafts are preferred, and staged repair is often necessary for panurethral disease. Long-term surveillance is essential to monitor for recurrence and meatal stenosis.

Radiation-induced strictures present unique challenges due to poor tissue vascularity and healing capacity. In these cases, gracilis muscle flap interposition may be required to provide tissue coverage. Repair techniques have higher failure rates in irradiated tissue, and urinary diversion should be considered in severe cases.

<image>Retrograde urethrogram radiographic image showing a 3 cm bulbar urethral stricture with proximal dilation, labeled anatomic landmarks including the membranous urethra and external sphincter, with measurement annotations of the stricture length and caliber</image>

## Key Clinical Pearls

Repeated DVIU after one failed attempt offers diminishing returns, and patients should be referred for urethroplasty rather than undergoing multiple endoscopic procedures. Excision and primary anastomosis for short bulbar strictures remains the definitive standard with the highest success rate exceeding 90%. Buccal mucosa is the gold-standard graft material, especially important to avoid genital skin in cases of lichen sclerosus. Prior to planning urethroplasty, a combined retrograde urethrogram and voiding cystourethrogram should always be obtained for complete stricture characterization. In pelvic fracture urethral injury, definitive repair should be delayed for three months, with acute management involving placement of a suprapubic catheter. Primary realignment endoscopically should only be attempted when expertise and ideal conditions are present. Patients must be counseled that urethral stricture disease is recurrent, necessitating long-term follow-up with uroflowmetry and symptom assessment after any intervention.

## References

1. Mangera A, Patterson JM, Chapple CR. A systematic review of graft augmentation urethroplasty techniques for the treatment of anterior urethral strictures. *Eur Urol*. 2011;59(5):797-814.  
2. Wessells H, Angermeier KW, Elliott S, et al. Male urethral stricture: AUA guideline. *J Urol*. 2017;197(1):182-190.  
3. Barbagli G, Guazzoni G, Lazzeri M. One-stage bulbar urethroplasty: retrospective analysis of the results in 375 patients. *Eur Urol*. 2008;53(4):828-833.  
4. Morey AF, McAninch JW. When and how to use buccal mucosal grafts in adult bulbar urethroplasty. *Urology*. 1996;48(2):194-198.