Trigone of urinary bladder

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== Trigone of Urinary Bladder ==

The trigone of the urinary bladder is a smooth triangular region of the internal urinary bladder. It is located between the openings of the two ureters and the urethra. The trigone is clinically significant because it is a common site for the development of urinary tract infections (UTIs) and bladder cancer.

Anatomy

The trigone is a triangular area demarcated by three points:

• The two ureteral orifices, where the ureters enter the bladder.
• The internal urethral orifice, where the bladder opens into the urethra.

The mucosa of the trigone is smooth and remains relatively fixed in position, unlike the rest of the bladder, which is highly distensible. This fixed nature is due to the underlying detrusor muscle and the presence of a submucosal layer of connective tissue.

Function

The primary function of the trigone is to act as a funnel, directing urine from the ureters into the urethra. The smooth nature of the trigone helps ensure that urine flows efficiently and prevents backflow into the ureters, which could lead to kidney infections.

Clinical Significance

The trigone is a critical area in the diagnosis and treatment of various urological conditions:

• **Urinary Tract Infections (UTIs):** The trigone is a common site for bacterial colonization and infection.
• **Bladder Cancer:** Tumors often develop in the trigone area due to its fixed position and constant exposure to urine.
• **Vesicoureteral Reflux:** This condition, where urine flows backward from the bladder into the ureters, can be associated with abnormalities in the trigone.

Related Structures

• Ureter
• Urethra
• Detrusor muscle
• Bladder

See Also

• Urinary system
• Bladder infection
• Urology