Urethral strictures are caused by gonococcal infection in 40% of cases, which is the most common cause of stricture in the US. The typical location of injury occurs at the bulbopenile urethra.
Radiographic features include: beaded appearance, retrograde filling of the glands of Littre. TB can numerous fistulas, resulting in a “watering can” appearance of the perineum.

Traumatic injuries to the urethra are probably the second most common cause of urethral strictures. 4-17% of pelvic fractures occur males and less than 1% in females have been associated with urethral injury, which predisposes to stricture. Post-traumatic strictures may also follow instrumentation (e.g. TURP, which is associated with a well-defined stricture at the penile scrotal junction or the bulbomembranous urethra), prior catheter insertion (irregular and long stricture at the penoscrotal junction), and injuries that include straddle mechanism (bulbar urethra), pelvic fractures (prostatomenbranous urethra).

Neoplasms may also result in urethra stricture. Polyps may be inflammatory or due to TCC (transitional cell carcinoma) papilloma. TCC accounts for 15% of malignant primary tumors and SCC, 80%. These often present with urethral stricture. Finally, prostate carcinoma may invade and cause stricture of the urethra.