Urethra

The urethra is the opening that allows urine to leave the bladder. In men, the urethra is a thin tube like structure that starts from the lower opening of the bladder and traverses the entire length of the penis. In women, it is a shorter opening coming off the lower opening of bladder and is between 2.5 to 4 centimeters (cm) in length. The urethra has a sphincter that is normally closed to keep urine inside the bladder. When bladder fills with urine, there are both voluntary and involuntary controls to open the urethral sphincter to allow urine to come out.

Stricture Urethra

Urethral stricture refers to any narrowing of the urethra for any reason whether or not it actually impacts the flow of urine out of the bladder. Any inflammation of urethra can result in scarring, which then can lead to a stricture or a narrowing of the urethra. Trauma, infection, tumors, surgeries, or any other cause of scarring may lead to urethral narrowing or stricture. Mechanical narrowing of the urethra without scar formation (developmental causes or prostate enlargement) can also cause urethral stricture. Urethral stricture is significantly more common in men and boys compared to women and girls. This condition is considered rare in females.

What are the causes of urethral stricture?

The following are common causes of scarring or narrowing of the urethra:

  • Trauma from injury or accidents with damage to the urethra or bladder (for example, falling on a frame of a bicycle between the legs, or a car accident)
  • Pelvic injury or trauma
  • Previous procedures involving the urethra (urinary catheters, surgeries, cystoscopy)
  • Previous prostate surgery (TURP or transurethral resection of the prostate)
  • Prostate enlargement
  • Cancer of the urethra (rare)
  • Infections of the urethra (sexually transmitted diseases or STDs, urethritis, gonorrhea, chlamydia)
  • Prostate infection or inflammation (prostatitis)
  • Previous hypospadias surgery (a congenital birth defect in which the opening of the urethra is on the underside of the penis instead of the tip)
  • Congenital malformations of the urethra, which rarely can cause urethral stricture in children

Symptoms of urethral stricture

Some of the possible symptoms and complications of urethral stricture include the following:

  • Difficulty starting urine flow
  • Painful urination (dysuria)
  • Urinary tract infection (UTI)
  • Urinary retention
  • Incomplete emptying of bladder
  • Decreased urine stream
  • Dribbling of urine
  • Spraying or double streaming urine
  • Blood in the urine (hematuria)
  • Blood in the semen
  • Urinary incontinence
  • Pelvic pain
  • Discharge from the urethra

Investigation for Stricture Urethra

Cystoscopy: Cystoscopy is endoscopy of the urinary bladder via the urethra. It is carried out with a cystoscope. The cystoscope is inserted into your urethra and slowly advanced into the bladder. Cystoscopy allows your doctor to look at areas of your bladder and urethra that usually do not show up well on X-rays. Tiny surgical instruments can be inserted through the cystoscope that allows your doctor to remove samples of tissue (biopsy) or samples of urine. Small bladder stones and some small growths can be removed during cystoscopy. This may eliminate the need for more extensive surgery.

Urethrography: A retrograde urethrogram is a routine radiologic procedure used to image the integrity of the urethra. Hence a retrograde urethrogram is essential for diagnosis of urethral injury, or urethral stricture. The procedure involves the insertion of a Foley catheter into the distal urethra and minimally inflating it. This is followed by instillation of 30mL of water soluble contrast and a plain radiograph is obtained; leakage of the contrast suggests urethral injury and is an indication for surgical intervention. If a urethral injury is suspected, a retrograde urethrogram should be performed before attempting to place a Foley catheter into the bladder. If there is a urethral disruption, a suprapubic catheter should be placed.

Uroflowmetry: Uroflowmetry is a diagnostic test that is administered to check for abnormalities in the amount or flow rate of a patient’s urine. The procedure is straightforward and painless, and simply involves urinating into a funnel device attached to an electronic meter. Doctors commonly use uroflowmetry to check for possible bladder obstructions, kidney problems, urethral stricture, prostate enlargement, and urinary tract infections. Unusual test results indicate the need for additional testing procedures, such as x-rays and sample lab analysis.

Treatment for urethral stricture

There are essentially no real medical treatments (medications) for urethral strictures other than those offering symptom controls (for example, pain medications to control discomfort). Surgery remains the only treatment for individuals with uncontrolled symptoms of urethral narrowing. Many surgical procedures are available for treating urethral strictures. Depending on the cause and other medical and social aspects, the most appropriate procedure may be recommended for each individual case. The common procedures include

Urethral dilation:

It is a commonly attempted technique for treating urethral strictures. This procedure is done under local or general anesthesia. Thin rods of increasing diameters are gently inserted into the urethra from the tip of the penis (meatus) in order to open up the urethral narrowing without causing any further injury to the urethra. This procedure may need to be repeated from time to time, as strictures may recur. The shorter the stricture, the less likely it is to recur after a dilation procedure. Occasionally, patients are given instructions and dilation instruments (rods, Teflon dilators, lubricating gel, and anesthetic gel) to perform the urethral dilation at home as needed.

Internal and Laser Urethrostomy:

The surgical technique of “Urethrotomy” creates a widening of the urethra using a special instrument. The operation is performed endoscopically through the external urinary meatus, progressing up to the area that narrows, without invasive surgery. There are two basic types of Urethrotomy:

  • Internal urethrotomy by cold knife (Sachse’s technique): In this procedure, the narrow part of the urethra is incised, cutting the stricture at 12 o’clock, with a cold knife, thus without cauterizing or using any other form of energy. The internal urethrotomy by cold knife is mainly used in patients with bulbar urethral strictures.
  • Holmium laser urethrotomy: In this procedure, the narrow part of the urethra is incised, cutting the stricture at 12 o’clock, using a holmium laser fiber. The Holmium laser urethrotomy is mainly used in patients with posterior urethral strictures or in patients with bladder neck contracture after prostatic surgery.

With these procedures, an endoscopic approach is used to open the urethra, in an outpatient service, day surgery or with a two-day hospital stay. Urethrotomy is generally suggested in the following cases:

  • Patients with bladder neck contracture after prostatic surgery.
  • Patients with simple and short bulbar urethral strictures who had no previous treatment.
  • Patients who refuse the standard surgical approach or who prefer to delayed surgery.
  • Elderly patients with urethral strictures associated with poor general health conditions where lengthy anaesthesia to perform complex urethral repair is not recommended.

Urethroplasty:

There are two types of urethral reconstruction. There are many surgical techniques with or without grafts that we can perform to repair urethral strictures and at the same time permit the aesthetic reconstruction of the glans and the penis. Urethroplasty is an open surgical procedure for urethral reconstruction to treat urethral stricture. It can be performed by 2 methods; primary repair which involves complete excision of the narrowed part of the urethra. The proximal and distal patent parts are then rejoined. The second method of Urethroplasty utilizes tissue transfer or free graft technique. In this method, tissue is grafted from foreskin or buccal mucosa and is used to enlarge the strictured (narrowed) segment of the urethra. Urethroplasty is performed under general anesthesia. Two urethroplasty techniques are popularly used:

  • Anastomotic Technique: In this method of urethroplasty, the narrowed part of the urethra is cut and the proximal and distal parts of the urethra are re-joined, a foley’s catheter will be left in for the next 2 weeks to ensure complete healing and repair. This method of urethroplasty is used for small urethral strictures i.e. less than 2 cm wide.
  • Tissue Transfer: In this method of urethroplasty, skin and tissue is grafted from a non-hair bearing part of the body like the buccal mucosa or bladder mucosa. Free grafts like Full Thickness Skin Grafts or Split Thickness Skin Grafts can be used for this purpose. Tissue Transfer Urethroplasty can be also be carried out in 2 stages if sufficient local tissue is not available for a Skin Flap Procedure and local tissue factors are not suitable for a free graft one stage procedure.

Johansen’s urethroplasty:

The Johansen’s procedure sometimes referred to as “Johansen’s urethroplasty” is a two stage procedure which was originally designed as a surgical repair for hypospadias. Over the years, the surgery has evolved into a fairly complex operation whereby the damaged area of the urethra is opened ventrally and left open as a buried skin strip with a deep diversion created from scrotal or penile skin covering the area of the repair. An appropriately sized in-dwelling catheter is inserted, and the repaired area is temporarily closed until the newly created diversion forms completely, usually within six months. Upon the confirmation of completed healing, the catheter is withdrawn and the surgical site closed permanently. There are numerous methods attributed to the name “Johansen’s”. Most severe urethral trauma is reconstructed using the Johansen’s urethroplastic procedure. It is also the procedure normally utilized in the repair of damage caused by balinitis lichen sclerosus, also referred to a BXO. The Johansen’s procedure is used in the most difficult of traumatic reconstruction cases. Because of the variations of practice within this procedure, an estimated success rate is not available.

Urethral stent placement:

Ureteral stents are soft, hollow, plastic tubes placed temporarily into the ureter to allow drainage around a stone or to speed healing after a stone surgery. Stents are used for various reasons in patients with kidney stones. They may be placed in patients to help reduce pain from a stone, when infection is present to allow drainage, or when a stone is preventing a kidney from working adequately. Stents are also commonly placed after surgeries for stones, as in ureteroscopy, to allow healing and prevent swelling of the ureter.

There are two general types of stents – permanent and temporary. Temporary stents can be further subdivided into removable and absorbable. Permanent stents are used where long term structural support or restenosis prevention is required, or in cases where surgical removal of the implanted stent is impractical. Permanent stents are usually made from metals such as Phynox, 316 stainless steel, MP35N alloy, and superelastic Nitinol (nickel-titanium). Permanent urethral stents are endoscopically placed. Stents are designed to be incorporated into the wall of the urethra and provide a patent lumen.