ABSTRACT
The functions of the bladder and lower urinary tract are storage and timely expulsion of urine, plus maintenance of a barrier between urine and plasma. The bladder is capable of accomplishing its storage function by accepting volumes of urine with little or no change in intravesical pressures. Continence is maintained by the sphincters of the bladder neck (internal sphincter) and the striated muscle of the urethral sphincter (external sphincter). Micturition is a finely tuned event coordinated by the opening of the sphincters and detrusor muscle contraction.
