About the urethra
The urethra runs through the prostate, which surrounds it like a doughnut. It is comprised of three sections and urethral strictures can occur in any part. Treatment depends on the location of the strictures, cause and prior treatments.
First, the urethra exits the pelvis through a muscular sphincter that stays closed at rest and opens during urination.
Next, the urethra widens into the bulbar urethra, the part of the urethra located between the sphincter and the base of the penis. The bulbar urethra is surrounded by a thick layer of spongy tissue called the spongiosum. Outside of the spongiosum is the bulbospongiosus muscle.
At the end of the muscle begins the penile, or pendulous, portion of the urethra. As the name implies, this is the part of the urethra on the underside of the visible portion of the penis.
Within the head of the penis (called the glans) the urethra widens to form the fossa navicularis before ending at the meatus.
When a scar from an injury, infection or swelling blocks the flow of urine in the urethra, it is called a urethral stricture. Men are more likely to have a urethral disease or injury because of their longer urethra. Therefore, strictures are more common in men.