40 To rule out dysfunctional voiding, a repeat uroflow is done with skin EMG electrodes on 9 and 3 O clock position close to the external sphincter of the rectum. 1,11, She comes back 1 hour after drinking 400 mls fluid and on USS has 280 ml in the bladder. When doing the prevoid ultrasound, she is asked if she can voluntarily contract the external anal sphincter without using the surrounding muscles. She has trouble doing this and therefore palpation on the perineal muscles is performed. (see below) After some practice she can contract the perineal muscles correctly. After this the EMG-electrodes are put in place; on either side of the outer anal sphincter. She is positioned on the examination bed in an upright sitting position with her feet on a foot stool. When watching the computer screen with the biofeedback program we talk about what a good relaxation of the pelvic floor feels like and looks like on the screen (How to do this see below) She is instructed to contract and relax the pelvic floor as she is lying down and the effect on the EMG is shown on the screen. Then she goes to the toilet and voids on the flowmeter.