The purpose of urodynamic testing is to assess the function and efficiency of the bladder in eliminating the urine, explains WebMD. Doctors may order urodynamic testing if a patient has moderate to severe involuntary urine release, if urinary incontinence has several causes, or if other tests fail to work.
Urodynamic testing can either be sophisticated or simple, according to WebMD. Sophisticated testing involves measuring the muscle electrical activity during the filling of the bladder by inserting electrodes into the rectum. In simple urodynamic testing, the doctor measures the urine volume and the emptying rate of the bladder during the patient's urination. He follows up by inserting a catheter into the bladder, measuring the remaining urine in the bladder and then adding water into the bladder until the patient urinates involuntarily.