Trigone of urinary bladder

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Trigone of urinary bladder
Illu bladder.jpg
Urinary bladder
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The interior of bladder.
Details
Identifiers
Latin trigonum vesicae urinariae
TA98 A08.3.01.024
TA2 3421
FMA 15910
Anatomical terminology

The trigone (also known as the vesical trigone) [1] is a smooth triangular region of the internal urinary bladder formed by the two ureteric orifices and the internal urethral meatus.

Contents

The area is very sensitive to expansion and once stretched to a certain degree, the urinary bladder signals the brain of its need to empty. The signals become stronger as the bladder continues to fill.

Embryologically, the trigone of the bladder is derived from the caudal end of mesonephric ducts, which is of mesodermal origin (the rest of the bladder is endodermal). In the female the mesonephric ducts regress, causing the trigone to be less prominent, but still present.

Pathology

Clinically important because infections (trigonitis) tend to persist in this region.

See also

Related Research Articles

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<span class="mw-page-title-main">Inferior vesical artery</span>

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Trigone may refer to:

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Ectopic ureter is a medical condition where the ureter, rather than terminating at the urinary bladder, terminates at a different site. In males this site is usually the urethra, in females this is usually the urethra or vagina. It can be associated with renal dysplasia, frequent urinary tract infections, and urinary incontinence. Ectopic ureters are found in 1 of every 2000–4000 patients, and can be difficult to diagnose, but are most often seen on CT scans.

<span class="mw-page-title-main">Duplicated ureter</span>

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<span class="mw-page-title-main">Gartner's duct cyst</span> Medical condition

A Gartner's duct cyst is a benign vaginal cyst that originates from the Gartner's duct, which is a vestigial remnant of the mesonephric duct in females. They are typically small asymptomatic cysts that occur along the lateral walls of the vagina, following the course of the duct. They can present in adolescence with painful menstruation (dysmenorrhea) or difficulty inserting a tampon. They can also enlarge to substantial proportions and be mistaken for urethral diverticulum or cystocele. In some rare instances, they can be congenital.

References

  1. Woodburne, Russell T. (1965-03-01). "The Ureter, ureterovesical junction, and vesical trigone" (PDF). The Anatomical Record. 151 (3): 243–249. doi:10.1002/ar.1091510305. hdl: 2027.42/49801 . ISSN   1097-0185. PMID   14324081.