Trigone of urinary bladder

Trigone of Urinary Bladder

The Trigone of the urinary bladder is a significant anatomical structure located in the lower part of the urinary bladder. It is a triangular-shaped area that is clinically important due to its involvement in various urinary disorders.

Diagram of the urinary bladder showing the trigone.

Anatomy

The trigone is defined by three points: the two ureteric orifices (where the ureters enter the bladder) and the internal urethral orifice (where the urethra exits the bladder). The area is devoid of rugae, the folds that are typically seen in the rest of the bladder lining. This smooth area allows for easy identification during cystoscopy.

Clinical Significance

The trigone is clinically significant as it is typically spared during bladder infections (cystitis). However, it can be involved in certain pathological conditions such as vesicoureteral reflux, where urine flows back from the bladder into the ureters, and bladder cancer.

See Also

• Urinary system
• Ureter
• Urethra