Gross Anatomy Depicting the Interureteric Crest (Urinary Bladder)

Description

Opening the female urinary bladder from its superior aspect exposes the mucosal surface of the trigone, bounded posterolaterally by the right and left ureteric orifices and inferiorly by the internal urethral orifice at the bladder neck. A raised transverse mucosal ridge, the interureteric crest (plica interureterica), spans between the ureteric openings on the posterior wall, just superior to the trigonal apex and immediately posterior to the vesical outlet. Surrounding rugae of the detrusor-lined bladder mucosa are seen on the more superior bladder body, while the trigone remains smooth, fixed, and sharply demarcated. Spatially, the crest lies posterior to the urethral lumen, inferior to the dome, and medial to the lateral bladder walls. A clean landmark. Clinically, the interureteric crest helps orient cystoscopic inspection of the trigone, where ureteric jets confirm upper urinary tract (renal) drainage and where inflammation can localize in trigonal cystitis. Its relationship to the ureteric orifices matters during transurethral procedures, including bladder biopsy or fulguration near the trigone, where inadvertent thermal injury can precipitate ureteric edema, obstruction, or vesicoureteral reflux. This view also supports teaching the continence mechanism: the short female urethra and bladder neck sit immediately anterior and inferior to the trigone, a zone often scrutinized in stress urinary incontinence evaluations and after pelvic surgery. Urology and pelvic anatomy courses use this plate to ground the cystoscopic anatomy of the trigone and to pair surface features with the underlying detrusor and ureterovesical junction. It also fits well in surgical atlases and patient-facing education for recurrent urinary tract infection workups, where clear identification of the ureteric orifices, interureteric crest, and bladder neck improves shared understanding. Anatomical accuracy verified by SciePro's Medical Advisory Board.