Pathophysiology
Clinical meaning
A urethral stricture is a narrowing of the urethra caused by scar tissue formation (fibrosis) within or around the urethral wall. This scar tissue develops in response to injury, infection, or chronic inflammation. Common causes include prior catheterization, urethral instrumentation (cystoscopy, surgery), sexually transmitted infections (particularly gonorrhea), and traumatic injury to the perineum or pelvis. The scar tissue reduces the diameter of the urethral lumen, creating resistance to urine flow. This leads to difficulty urinating, weak stream, straining, incomplete bladder emptying, and potentially urinary retention. Strictures occur almost exclusively in males due to the longer urethral length and are most common in the bulbar urethra.