Editing Bladder (section)

== Ureterovesical junction and the trigone ==

* The ureter pierces the bladder wall obliquely, travels 1.5-2 cm, and terminates at the ureteral orifice
* '''Vesicoureteral reflux is thought to result from (2):'''
*# '''Insufficient submucosal ureteral length'''
*# '''Poor detrusor backing'''
* Bladder filling is thought to result in passive occlusion of the ureter, like a flap valve.
* A hutch diverticulum is herniation of bladder wall at the weakest point of detrusor hiatus, above ureter
* The triangle of smooth urothelium between the two ureteric orifices and the internal urethral meatus is referred to as the trigone of the bladder
* '''Smooth muscle of the ureter forms the interureteric ridge (Mercier bar)'''
* The urothelium overlying the muscular trigone is usually only 3 cells thick
* Bladder neck is 3-4cm behind midpoint of pubic symphysis
* '''Layers of trigone muscle (3):'''
*# '''Superficial layer, derived from the longitudinal muscle of the ureter.'''
*# '''Deep layer, derived from Waldeyer sheath on the ureter and inserts at the bladder neck.'''
*# '''Detrusor layer.'''