Urinary Tract Stenosis-Urethra Stenosis

What is Urethra Stenosis?

The urethra is the urethra between the tip of the penis and the bladder that allows urine to be carried out of the body. Urinary tract stenosis (urethral stenosis) is a mechanical disease that prevents the urine from coming out of the bladder and evacuating comfortably, resulting in the accumulation of urine in the bladder and the inability to empty the bladder completely.

Urethral stricture is a disease that affects approximately 0.5-1% of men and results in fibrosis (scar) in the epithelium or the structure that forms the urinary canal body (corpus spongiosum) as a result of damage to the urinary tract cells (urethral epithelium) for some reason. The stricture is caused by injury or damage to the urethra and surrounding tissue. For example, if a stretching and thickening (scar tissue) occurs in the injured area in the injuries on the skin, a scar tissue occurs in the urethra injuries as well. accumulates, not fully discharged.

Traumas, some medical applications such as radiotherapy for prostate cancer, some surgical operations in this region and some infections such as gonorrhea can cause urethral stricture. The causes of urethral stricture vary according to the age of the patient and the location of the stricture. Anterior urethral strictures are mostly caused by inflammation (40%), medical intervention (iatrogenic-40%) or trauma, while posterior urethral strictures are iatrogenic after pelvic fracture (pelvic fracture) or as a result of surgical intervention. Sometimes no cause can be found (15-20%). The strictures can range in length from a few millimeters to a few centimeters between the bladder and the tip of the penis.

Symptoms and Diagnosis

  • clinical history

  • Symptom scoring (Patient Reported Outcome Measure)

  • physical examination

  • Uroflowmetry and Ultrasonography, residual urine amount

  • urethrography

  • Urethro-cystoscopy (in some cases)

Patients with urethral stenosis usually present with lower urinary tract symptoms and signs. Patients apply with complaints such as difficulty urinating, weakening in the urine stream, feeling of not being able to empty the bladder completely, dripping after urination, frequent toilet visits. Sometimes patients may present with recurrent urinary tract infections, prostatitis, epididymitis-orchitis or bladder stones. It should be kept in mind that sudden inability to urinate (retention) may develop in complete stenosis or obstruction.

In urethral stenosis, a detailed history of the cause should be taken before treatment. It is important to evaluate urinary hole pathologies in physical examination and to palpate the scar tissue in the anterior urethra in cases called lichen sclerosis. Maximum urine flow rate and voiding pattern should be evaluated with voiding test (uroflowmetry) in patients with urethral stenosis. Ultrasonography may be required to evaluate bladder pathologies and to measure the amount of urine that cannot be emptied (residual). Retrograde urethrography (RUG) may be performed to evaluate the exact location and length of the urethral stricture. Retrograde urethrography is the gold standard, especially for the diagnosis of anterior urethral strictures. However, since RUG is insufficient in posterior urethral strictures and bladder neck pathologies, a combination of voiding (voiding) cystourethrography (MSU) and RUG should be performed in these vales.

In cases where the diagnosis cannot be decided, urethrocystoscopy may be required to clarify the stenosis. Flexible cystourethroscopy with simultaneous external urethral hole (meatus) or cystostomy can be an important diagnostic tool to measure the location and length of the stenosis. After the location and length of the stenosis are clarified, the type and time of intervention is planned.

Treatment

Treatment of urethral strictures may vary depending on the cause (etiology), location (anterior, posterior), number, length of the narrow area, density-severity of the stenosis (degree of spongiofibrosis), previous treatment attempts, and the age of the patient. Relatively short simple strictures are treated endoscopically, while long-complex strictures are treated with one or two-stage open surgery (urethroplasty).

Urethral enlargement (dilatation): It can be done with metal dilators, balloon dilatation or nelaton catheters. This form of treatment can provide a temporary relief to the patient by opening the scar formed in short segment stenosis (<1 cm). It is generally applied to patients with additional diseases (high comorbidity), who cannot afford another additional intervention, and who have a limited life expectancy. However, in short stenoses without severe scar tissue (spongio-fibrosis), it can provide complete treatment (curative) even though it is rare. urethral dilations; It can be tried in the treatment of bulbar urethral stenosis, outer hole and stenosis close to the outer hole (Meatalfossa navicularis), stenosis in the urinary valve region (Sphincteric stenosis).

Internal Uretrotomy (IU): Uretrotomy interna 17-20 F It is the process of cutting the short urethral stenosis at the 12 o’clock position with a cold knife with a urethroscope. This method has been widely used for about fifty years. Various lasers (Argon, carbon dioxide, excimer, diode, KTP and other lasers) are used in the treatment of urethral stenosis in addition to the cold knife. Nd:YAG lasers) are used. In general, it is reported that the success of laser urethrotomy is the same as cold knife. After urethrotomy Internal, scarred epithelial tissue is left for secondary wound healing and epithelialization creates a new urinary tract (urethral lumen) and its continuity. If normal healing (epithelialization) occurs before scar tissue (contraction), the procedure is successful, otherwise, if the wound contraction occurs faster, recurrence of stenosis is almost inevitable.

Complications : The most common main complication of urethrotomy interna surgery is recurrence of stenosis. Other complications (0.5-5%) are usually encountered as bleeding, hematoma, and epididymo-orchitis. In some rare cases, deep cuts (incisions) may cause a fistula between the penile corpus cavernosum and the urinary canal (corpus spongiosum), leading to impotence (erectile dysfunction).

Urethroplasty: Uretroplasty is the most effective method for the complete treatment of urethral strictures and is considered the gold standard. In this method, the stenosis area is removed and then urethral reconstruction is performed either with an end-to-end anastomosis or using a flap/graft.

1-Removal of the stenosis and end-to-end anastomosis (Excision and primary anastomosis): In this treatment method, the aim is to perform an end-to-end anastomosis in accordance with the urethra method (spatula and not taut) after the scar tissue (fibrotic tissue) is completely removed. In stenoses longer than 2 cm (in cases where augmentation urethroplasty is not possible), the two corpus cavernosum tissues are carefully separated to reduce the end-to-end anastomotic tension. With this method, approximately 5 cm of stenosis can be anastomosed end-to-end, but if tension still occurs, a part of the pubic bone can be cut (inferior pubectomy). In addition, end-to-end joining (anastomosis) performed especially in anterior urethral stenosis over 2 cm, shortening of the penis length and penile curves (curvature) may occur. Therefore, it is necessary to use augmentation urethroplasty techniques in long segment stenosis.

2-Augmentation Urethroplasty: This treatment method is generally preferred in cases longer than 2 cm and end-to-end anastomosis urethroplasty is not suitable. This method is done in one or two stages. Recurrence of stenosis in augmentation urethroplasty has been reported with a rate of 14-15%. Penile skin, scrotal skin, oral mucosa, bladder mucosa, and colonic mucosa can be used for grafting. Among these, it is the most preferred material with its ease of obtaining the oral mucosa, absence of scalp, low complication and high success rate. Oral mucosa can be obtained from the cheeks, lips or tongue. Intraoperative bleeding, postoperative pain, infection, swelling, and salivary gland duct injury are reported complications related to oral mucosal graft use. Temporary difficulty in opening the mouth may be observed in some patients. Island flap/graft (Onlay grafts) are used as anterior, lateral and posterior.

3-Two-stage urethroplasty: It is applied in penile urethra and especially in cases with unsuccessful hypospadias surgery or lichen sclerosis. After the first stage, 10-39% of severe stenosis (contraction) may be seen due to the graft scar. Therefore, it is necessary to wait 3 to 6 months for the second stage.

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