A urethral stricture is condition when a collection of dense scar tissue which deposits within the urethra, the urinary channel that carries urine from the bladder through the prostate and out through the penis. Urethral strictures cause obstruction that can lead to troublesome urinary symptoms. This includes poor urinary flow, painful urination, retained urine, recurrent urinary tract infections, and painful ejaculation.
In many cases we do not know. Some of the most common causes are trauma (pelvic fracture or a blow to the area behind the scrotum,) urinary tract infections, previous urinary catheters, radiation for prostate cancer, scarring from previous urologic procedures, and previous surgery for hypospadias.
Urethral strictures are best diagnosed by an x-ray of the urethra called a retrograde urethrogram (RUG), or a cystoscope procedure. For the X-ray contrast dye is injected into the urethra and images of the urethral stricture is obtained. These x-rays help determine the diameter of the strictures as well as its length. Often an initial diagnosis of stricture is made by a cystoscope procedure. A urologist can pass a flexible scope (similar to a catheter) up the urethra to find a stricture by visualizing its opening.
Figure 1 - A urethral stricture seen from a scope placed within the urethra
Figure 2 - An X-ray of the urethra showing a narrow stricture near the prostate.
There are a variety of treatments for urethral strictures, which range from scope procedures to internally cut or break open the scar to open surgical procedures called urethroplasty. Often patients are treated initially with one of the internal scope procedures. The scope procedures are referred to as endoscopic treatments and include urethral dilation and direct vision internal urethrotomy. Dilation of the urethra involves passage of a metal rod or other instrument to stretch the stricture internally. Direct vision internal urethrotomy involves cutting the stricture with a very small knife that emerges from a scope. Both methods have approximately the same success, which is often poor. Even with most favorable strictures (short and soft), dilation or direct internal vision urethrotomy may achieve a long-term success in about 1/3 of patients. When strictures return after one scope procedure, additional scope treatments are very rarely successful.
Urethroplasty is general term meaning open repair of the urethra. It is varied and involves many different techniques.
If strictures are short and in certain portions of the urethra, the constricted area of the urethra can be surgically removed and the healthy urethra can be reconnected. This is called anastomotic urethroplasty.
If the urethral stricture is lengthy, other tissues need to be used to reconstruct the urethra. One common tissue used is the lining of the inner cheek; this is called buccal mucosa. Buccal mucosa is preferred because it has a tissue characteristics very similar to the native lining of the urethra (hairless and smooth). Because the mouth heals very well after harvest of this graft, it has become one of the most common surgical options.
If the stricture is very lengthy a piece of hairless skin may be used. This is referred to as a penile fasciocutaneous flap and can be used on strictures that stretch throughout the penis. Close follow up and appropriate treatment of urethral strictures is very important in order to avoid urethral stricture recurrence and prevent the serious complications that can result like kidney failure, chronic urinary retention or life threatening infections.