bubble_chart Overview

Urethral stricture is more common and severe in males.

bubble_chart Clinical Manifestations

Urethral strictures can be classified into spasmodic and organic types; the latter includes congenital and acquired forms.

1. **Spasmodic Urethral Stricture** This is a temporary condition caused by the contraction of the external urethral sphincter. Precipitating factors may include urethritis, urethral calculi, the use of urethral instruments, or abnormal sexual desire. Sometimes, it may also result from reflexive stimulation due to lesions in the perineum, rectum, or pelvic cavity, or purely from psychological factors. Urethral spasms occur in the membranous portion, making it difficult to distinguish from organic strictures of the bulbous and membranous portions. When a blunt instrument encounters resistance in the urethra (e.g., a catheter or cystoscope), gentle and continuous pressure may be applied. If the stricture is spasmodic, the urethra often suddenly relaxes, allowing the instrument to pass. Under anesthesia, spasmodic strictures can completely relax without causing obstruction. Cystourethrography is quite helpful in diagnosis. Comprehensive treatment for spasmodic strictures includes eliminating precipitating factors, sitz baths with warm water, sedatives, analgesics, and antispasmodics. For severe bladder distension, acupuncture may be used. Catheterization is employed when necessary.

2. **Organic Stricture** Clinically, this is more common than spasmodic strictures.

- **Congenital Stricture** Commonly seen at the external urethral orifice, often accompanied by redundant prepuce or phimosis. The external urethral orifice in cases of epispadias or hypospadias is also usually narrower than normal. Anterior urethral valves are often septal, forming a double-cavity anterior urethral deformity, whereas posterior urethral valves typically have a small central opening, causing dribbling urination. Urethral lumen strictures are most common at the junction of the bulbous and membranous portions and the posterior end of the navicular fossa.

- **Acquired Stricture** These can be divided into traumatic and inflammatory strictures based on etiology. Trauma is the most common cause of urethral strictures, often resulting from perineal straddle injuries, pelvic fractures causing membranous urethral injury, or intraurethral injuries from instrument manipulation. When the urethra suffers severe trauma affecting the submucosal and mural layers, the urethral muscle layer and surrounding fasciae exhibit congestion, edema, and hemorrhage. During the healing process, the injured tissue forms fibrosis. As scar tissue contracts, the urethral lumen often narrows, so strictures typically appear months after the injury. Generally, longitudinal trauma less commonly leads to scar strictures. Inflammatory strictures are seen in gonorrhea, urethral subcutaneous nodules, or nonspecific urethritis. In acute urethritis, the submucosal layer and peri-glandular tissues are infiltrated by inflammation. During the chronic phase, inflammation gradually resolves, leading to fibrosis and urethral strictures. Thus, inflammatory strictures often develop one or several years after acute urethritis. Strictures caused by inflammation are more extensive and involve more scar tissue than those due to trauma, making treatment more difficult. Indwelling catheters, urethral foreign bodies, calculi, or diverticula can induce urethral infections. Phimosis-associated balanoposthitis can lead to external urethral orifice strictures, often delaying treatment and allowing inflammation to spread backward, resulting in long-segment anterior urethral strictures. Whether due to trauma or inflammation, urethral strictures often lead to proximal urethral dilation due to urinary retention, and urinary infections exacerbate fibrosis, worsening the degree and extent of the stricture. In urethral strictures, the urethral lumen is narrow, but a few patients may still pass a catheter or urethral sound smoothly. However, due to surrounding scar compression, voiding difficulties persist, a condition some refer to as "elastic urethral stricture."

The symptoms of urethral stricture can vary depending on its severity, extent, and progression, with the primary symptom being difficulty in urination. Initially, there is straining during urination, prolonged urination time, and splitting of the urine stream. Gradually, the urine stream becomes thinner, the range of urination shortens, and it may even become dribbling. When the detrusor muscle contracts but cannot overcome the urethral resistance, residual urine increases, leading to overflow incontinence or urinary retention. Urethral stricture is often accompanied by chronic urethritis. In such cases, a small amount of purulent discharge is often observed at the external urethral orifice, typically noticed in the morning, where the urethral opening is sealed by one or two drops of discharge, referred to as "morning drop." The proximal urethra dilates, making it prone to complications such as recurrent urinary tract infections, periurethral abscesses, urethral fistulas, prostatitis, and epididymitis due to urine retention and infection. Subsequently, obstruction can lead to hydronephrosis and hydroureter, along with recurrent urinary tract infections, ultimately resulting in renal function decline and even uremia.

bubble_chart Diagnosis

The diagnosis of urethral stricture should be established based on medical history, signs, urethral instrumentation, and urethrocystography. The application of urethral instruments not only confirms the presence of a stricture but also determines its location, number, severity, and type. Commonly used instruments include catheters, filiform bougies, and urethral sounds. Urethral instrumentation must be performed under strict aseptic conditions and adequate anesthesia. If the patient has undergone a suprapubic cystostomy, a urethral sound can be simultaneously inserted through the bladder incision from the internal urethral orifice. A lateral X-ray film can estimate the length and location of the urethral stricture. If the urethral sound can pass through the strictured segment, it can be replaced with a thicker sound for urethral dilation, which is also an effective treatment. Generally, it is advisable to start with an F20 size. If it cannot pass, a thinner sound should be used. However, when using a thin urethral sound for exploration, even with a finger guiding in the rectum, there is still a risk of perforating the urethral wall or creating a false passage. Therefore, forceful manipulation must be avoided. Alternatively, a filiform bougie can be used as a guide for inserting the urethral sound.

Urethrocystography is particularly suitable for cases where the strictured segment has a very small lumen or cannot be traversed by a urethral sound. Retrograde urethrography involves injecting contrast medium through the external urethral orifice while taking lateral films, which clearly shows the distal end of the strictured segment. After the contrast medium is injected into the bladder, the patient is asked to void while a lateral urethral film is taken (i.e., antegrade urethrocystography), which better visualizes the proximal end of the strictured segment. If the patient has a cystostomy, contrast medium can be injected through the stoma tube, followed by a lateral urethral film during voiding. Urethrocystography can also differentiate between spasmodic and organic urethral strictures and reveal urinary fistulas. Urethroscopy allows direct visualization of the distal end of the strictured segment from within the urethra.

bubble_chart Treatment Measures

1. Non-surgical Treatment Non-surgical treatment primarily relies on urethral dilation. Even for post-surgical cases, regular dilation is necessary to prevent restenosis. Urethral dilation should not be performed during acute urethral inflammation and must be conducted under adequate anesthesia and strict aseptic conditions. Forceful dilation should be avoided. If necessary, a finger should be placed in the rectum to guide the procedure and prevent false passage formation or even rectal perforation. Dilation must proceed gradually, starting with smaller probes and sequentially increasing to larger ones, avoiding haste. Overly rapid dilation can lead to urethral wall lacerations, followed by scar formation and worsening stenosis. Generally, dilation up to F24 is appropriate for males. After each urethral dilation, urethral congestion and edema occur, typically subsiding within 2–3 days. Therefore, dilation should not be repeated within 4 days. The interval between sessions usually starts at around 1 week and is gradually extended.

Instilling urethral irrigation fluid can prevent restenosis, achieving a "soft dilation" effect. Physical therapies such as audio frequency and iodine iontophoresis can accelerate scar softening and consolidate the dilation results.

2. Surgical Treatment Patients with urethral strictures for whom non-surgical treatment has failed may opt for appropriate surgical interventions. There are many surgical methods, and the choice depends on the surgeon's experience, the patient's stricture condition, and available medical resources.

1. **Urethral Meatus Incision** Suitable for cases of urethral meatus stricture, often seen in patients with balanoposthitis, partial penectomy, or post-hypospadias repair. A longitudinal incision can be made on the ventral side of the urethral meatus to create a grade I hypospadias. The incised urethral mucosa on both sides is sutured to the glans skin for hemostasis.

2. **Internal Urethrotomy** For very short strictures or even membranous strictures, a specialized cold knife can be used under direct urethroscopic visualization to incise the stricture ring. The procedure can be guided by inserting a thin ureteral catheter. If necessary, excess scar tissue can be excised with an electrocautery knife. If the posterior urethral stricture is completely occluded but not lengthy, the bladder can be incised, and a finger inserted into the bladder to guide the passage using a resectoscope or urethral probe. A resectoscope is then inserted to excise the scar and create a channel. A long-term indwelling catheter (20 days or more) is placed to allow healing. Some advocate leaving several thin silicone tubes in the urethra for 3 months postoperatively, allowing urine to pass between the tubes during voiding, which also serves as a hydraulic dilation, yielding better outcomes. For multiple long-segment strictures, an Otis internal urethrotome can be used if feasible. The depth of the incision is controllable.

3. **Resection and Reanastomosis of the Strictured Urethral Segment** For cases unsuitable for internal urethrotomy, an appropriate incision is selected under good exposure to resect the strictured urethral segment and surrounding scar tissue. Hemostasis is ensured, and the urethral ends are everted and anastomosed with absorbable sutures under no tension. The wound should be thoroughly drained, and a catheter is retained for 2–3 weeks postoperatively. A minimally irritating silicone catheter should be used. For posterior urethral strictures, a suprapubic abdominal approach may be chosen, with partial pubic symphysis resection if necessary for better exposure. For bulbomembranous urethral strictures, a perineal curved or straight incision is suitable. During surgery, injury to surrounding normal tissues should be minimized to avoid excessive postoperative scarring and impotence. To reduce anastomotic tension, the distal urethra can be mobilized, even up to the coronal sulcus, but the proximal urethra should not be excessively mobilized. For difficult posterior urethral stricture resections and anastomoses, a long straight needle can be used for anastomosis through the abdominoperineal wound. Alternatively, the distal urethral end can be fixed to a catheter with a suture, pulled into the bladder to approximate the ends, and the catheter secured as a stent to achieve alignment.

4. Urethrotomy for Stricture Segment Applicable to penile urethral strictures or long urethral strictures that are difficult to repair in the initial stage [first stage]. The strictured segment of the urethra is incised or excised, and new stomas are created at the distal and proximal urethral ends to form a hypospadias. Repair is performed 3 months later according to the hypospadias procedure. For penile urethral strictures, initial stage [first stage] excision and reanastomosis often result in urethrocutaneous fistulas. Difficult-to-repair posterior urethral strictures can also be managed by perineal tunneling, followed by pulling a perineal or scrotal skin flap into the tract and suturing it to the bladder neck to create a perineal-type hypospadias, which is then repaired in the intermediate stage [second stage].

5. Urethroplasty The defective urethra can be reconstructed using autologous bladder mucosa, pedicled bladder flaps, pedicled skin flaps, and/or intermediate-thickness skin grafts.

6. Urinary Diversion Generally, urethral stricture surgery requires simultaneous bladder ostomy to divert urine and ensure surgical success. For patients with failed surgeries, bladder ostomy can be maintained for subsequent procedures or as a permanent solution.

Urethral stricture surgery is a challenging procedure. Preoperative preparation must be thorough, the surgical plan meticulously designed, and regular dilation follow-ups conducted to achieve optimal outcomes. Postoperative complications such as recurrent strictures, urinary fistulas, impotence, and incontinence are relatively common.