A urethral stricture is an unnatural constriction of the urethra that causes obstructive urinary symptoms. It is usually caused by scar tissue. Damage to the urethral mucosa and adjacent tissues frequently results in these strictures.
Because urethral strictures are uncommon in women despite being possible in both sexes, there are few recommendations for diagnosing and treating female strictures.
Although strictures can form anywhere throughout the urethra in males, they are most frequently detected in the bulbar urethra and can have a variety of causes.
Etiology
The etiology of urethral strictures is classified into 4 major groups—idiopathic, iatrogenic, inflammatory, and traumatic, with idiopathic and iatrogenic being the most common, each accounting for 33%.
Inflammatory reasons make up 15%, while trauma causes make up 19%.
Infection may account for up to 26.6% of all patients undergoing urethroplasty, as the strictures tend to be relatively long, typically >4 cm.
Iatrogenic Causes
- Prolonged catheterization (36%): This treatment causes pressure on the urethra, which causes urothelial necrosis and rubbing or frictional damage to the urethral mucosa from the movement of the catheter.
- Simple Foley catheterization and cystoscopy (12.7%) can cause strictures by harming the urethral epithelium.
- Hypopadias repair: 6.3% of iatrogenic strictures are brought on by hypospadias repair.
- Radical prostatectomy (3.2%): Radical prostatectomy is another cause of urethral strictures.
Inflammatory Causes
Most frequently caused by recurrent gonococcal urethritis, postinfectious inflammation can constrict the lumen and damage the epithelium, resulting in inflammatory strictures.
Moreover, lichen sclerosus (balanitis xerotica obliterans) is frequently the source of meatal and urethral strictures. There may be an autoimmune component and a hereditary susceptibility, but the exact cause and pathophysiology of the illness are yet unknown. On the glans encircling the anus and the urethral meatus or vulva, lichen sclerosus manifests as pale, ivory lesions.
Traumatic Causes
The most prevalent cause of posttraumatic anterior urethral strictures is compression of the bulbar urethra against the symphysis pubis, which occurs as a result of straddle injuries. Rarely is this pattern of injury linked to a pelvic fracture.
Pathophysiology
The pathophysiology of urethral stricture involves injury to the urethral epithelium attributed to any of the specific etiologies causing leakage of urine into the corpus spongiosum or by direct trauma to the corpus spongiosum. Either of these etiologies initiates inflammation and fibrous changes in the corpus spongiosum. This fibrous tissue builds up and shrinks, causing contraction and compressing the urethral lumen
History and Physical
A urethral stricture should be considered in any male patient presenting with unexplained dysuria, a weak urinary stream, incomplete emptying, increased post-void residual urine volume, or a UTI.
Even though a physical examination is frequently nondiagnostic, it is nevertheless crucial to conduct a thorough examination. The physician should check for skin abnormalities, such as pale areas suggestive of lichen sclerosus, and palpate the urethra for any palpable fibrous tissue during the physical examination.
Evaluation
Urinary stricture is first identified by the history and physical examination, urinalysis, symptomatology, post-void residual urine volume, and peak urinary flow measures. Alpha-blocker drugs may not be effective in treating obstructive urinary symptoms, which may indicate a hypotonic detrusor or urethral stricture.
The diagnosis of urethral strictures is made and confirmed by voiding cystourethrography, retrograde urethrography, or cystoscopy.
RGU Showing Bulbar Urethral Stricture
Cystoscopy Image Showing Urethral Stricture
Treatment / Management
General Considerations
The goal of therapy is to alleviate symptoms when there are no consequences. The location, severity, duration, and patient preference of the stricture should all be taken into account during the therapy process.
Treatment options for acute urine retention in urethral stricture issues include direct vision internal urethrotomy (DVIU), suprapubic cystostomy, cystoscopy, and urethral dilatation.
Therapies for urethral strictures can be broadly divided into two categories: open surgical techniques, including stricture excision and anastomosis, urethroplasty, and perineal urethrostomy, and endoscopic procedures, like urethral dilatation and internal urethrotomy. Before choosing a final intervention, the stricture’s length and exact location should be identified.
Urethral dilatation: For a long time, urethral dilation with sound and boogies was the accepted first line of treatment. Tissue stretching and stricture disruption or widening result from the insertion of urethral dilators and their sequential size increases.
Direct vision internal urethrotomy:
When performing DVIU, a transurethral incision is made at the 12 o’clock position to relieve the stricture. This allows the urethral lumen to enlarge by secondary intention. With the highest success rates, this method is used as the first line of treatment for bulbar strictures that are brief (less than 2 cm) and have not been treated previously.
The decision of whether to go straight to a urethroplasty or perform a repeat DVIU after the previous procedure recurs is up for dispute. While some doctors advise a urethroplasty as the best course of action following a recurrence, others advise trying DVIU at least once more following the initial treatment.
Intermittent self-catheterization: After first therapy, intermittent self-catheterization on a regular basis helps keep the urethral lumen open.
VIU
VIU
Urethroplasty: This procedure entails resecting or opening the stricture and replacing the strictured urethral tissue with either a flap of normal skin, graft materials such buccal mucosa or foreskin, or a direct anastomosis for short (<2 cm) bulbar strictures. With a high overall success rate of >85%, this treatment usually produces good results and can be used for prolonged strictures.
Relatively rare urethroplasty complications include chordee, neuropraxia, fistulas, incontinence, erectile dysfunction, and UTIs.
Anastomotic urethroplasty:
Stricture excision and end-to-end anastomosis are more frequently referred to as anastomotic urethroplasty. This method works best when the stricture is brief (less than 2 cm) and in the bulbar urethra, which frequently happens after a traumatic straddle-type injury.
Substitution or graft urethroplasty:
Using this procedure, the urethra is mobilized in the strictured area, separated from the corpora cavernosa, and then opened longitudinally along the stricture’s length.
this procedure can be performed through a ventral, dorsal, or lateral approach. To widen the urethra, a skin graft is sutured to the defect.
The oral mucosa, foreskin, and infrequently the upper inner thigh can also be used as sources for skin grafts. Because of its histological characteristics and resilience to urine exposure, the oral mucosa makes the best transplant material.
Any penile urethral stricture or bulbar stricture too lengthy for a direct anastomotic urethroplasty should be treated with substitution urethroplasty.
For patients with complicated urethral strictures, such as those who have had lichen sclerosus, urethral reconstruction, or hypospadias treatment in the past, a two-stage procedure is advised.
BMG URETHROPLASTY
BMG URETHROPLASTYPerineal urethrostomy
Patients who have had numerous stricture procedures, have generally severe or difficult stricture disease, or do not want to have substantial future surgeries are the only ones eligible for this palliative procedure. Patients with numerous comorbidities who are unable to endure a urethroplasty may also benefit from perineal urethrostomy.
Complications
If left untreated, urethral strictures can lead to several complications, including:
- Acute urinary retention
- Bilateral vesicoureteric reflux
- Bladder diverticulum
- Erectile dysfunction
- Penile curvature or shortening
- Recurrent UTIs
- Voiding dysfunction
- Urethrocutaneous fistula