What is stenosis (narrowing) of the urethra?
The urethra is a tube that drains urine from the urethra. In men, it has 4 portions: the prostatic urethra (where the prostate is located), the membranous urethra (where the urethral sphincter is located), the bulbar urethra and the penile urethra. Any of these places is susceptible to urethral stricture.
What are the causes of urethral stricture?
Narrowing of the urethra is usually caused by inflammation or trauma. Occasionally it occurs congenitally, i.e. at birth. Examples of inflammation include sexually transmitted infections (STIs), prolonged probing, lithiasis, left lichen (balanitis xerotica obliterans - BXO) etc. Trauma can occur in cases of urethral instrumentation in urological procedures or external trauma, such as a fractured pelvis, a fall from a horse (with trauma to the perineum, e.g. a skateboarder's trauma on a handrail).
What are the symptoms of urethral stricture?
The urethra obstructs the flow of urine, so the symptoms are related to the emptying of the bladder. There is difficulty urinating, a weak, interrupted stream, with abdominal straining. Hesitation is common, indicated by the delay in starting urination. There may be urgency to urinate and urine leaking onto clothing. If there is urinary retention, there may be pain in the lower abdomen and urinary incontinence due to overflow.
What are the consequences of urethral stricture?
Urethral stricture causes difficulty urinating and/or symptoms of uncontrollable urine retention. In addition to the symptoms, which are extremely uncomfortable, it can cause organic problems. It is an important risk factor for urinary infection, which can cause kidney damage. The retention of urine in the bladder can lead to the development of bladder stones.
As the bladder is a muscle, obstruction of the urethra causes the bladder muscles to work harder to expel urine, leading to muscle growth (hypertrophy). Hypertrophy can lead to an increase in bladder pressure with consequent difficulty in renal drainage and renal dilation (hydronephrosis). Difficulty emptying the bladder can lead to the formation of diverticula and reflux of urine into the kidneys. If the obstruction persists, urinary retention tends to occur. As the urethra is narrowed, it is usually not possible to pass the tube through this route, requiring the placement of a tube into the bladder via the abdominal route (cystostomy) on an emergency basis.
How is urethral stricture diagnosed?
Urethral stricture must be ruled out in all individuals presenting with the above symptoms. Ultrasound usually reveals incomplete emptying of the bladder, with thickened bladder walls, and there may be diverticula.
The kidneys may be dilated.
Uroflowmetry will detect a reduced flow with a flat or interrupted pattern. However, the diagnostic test is urethrocystography. This consists of urethral probing and the introduction of contrast through the urethra into the bladder. A finding of a reduction in the caliber of the urethra is diagnostic. Sometimes there is a complete interruption of the flow of contrast, showing the absence of a patent urethral lumen.
What is the indication for internal urethrotomy?
Internal urethrotomy has a limited place in the treatment of short stenosis (maximum 1 cm) of the urethra, being more indicated in congenital or acquired stenosis.
Due to the very favorable results of open surgery (urethroplasty), the high rate of recurrence of internal urethrotomy and the knowledge today that when it recurs after urethrotomy, the stenosis tends to get worse, urethroplasty is preferred as the first course of action in most cases.
When urethrotomy fails, a new urethrotomy is not indicated, as the rate of restenosis is almost 100%.
What is urethroplasty?
It is the open surgery associated with the highest success rate in narrowing the urethra. Access will vary according to the site of the narrowing, which can be penile, perineal or both.
How is urethral stricture surgery currently performed?
Traditionally, urethral stricture was treated by removing the stenosed area and reconnecting (reanastomosing) the healthy stumps. Although this may be true for membranous urethra and bladder neck stenosis, it is not the case for the majority of stenoses.
The best tissue used for the urethra is the mucosa of the oral tissue, with the lower lip, cheek or lower portion of the tongue being the most commonly used. The use of tissue as an extracellular matrix or from tissue engineering (cell culture) are experimental procedures with no proven results and should therefore be used in research protocols.
What are the results of surgery for urethral stricture (urethroplasty)?
In experienced hands, the success rate is usually higher than 80% of cases. The patient usually returns to urinating with a good urinary stream.
What are the complications of urethral stricture surgery?
The main complication is restenosis, which is usually smaller than the previous one and can be treated with internal urethrotomy or new surgery. Urinary incontinence is another complication. However, incontinence is usually due to the primary cause and is not caused by the surgery. It occurs mainly in cases of extensive trauma to the posterior urethra, mainly due to car accidents, or due to urethral stenosis after surgery or radiotherapy for prostate cancer.
Erectile dysfunction is another situation that is usually the result not of the surgery, but of the situation that caused the stenosis. Both urinary incontinence and erectile dysfunction can be treated. Fistula (leakage) of the urethra can occur rarely and is treated with probing