How will a vcug test be done on my. do i have to pee while i lie down?

Here are...: Vcug is done under fluoroscopy(x-ray) to visualize if any significant urine backflow from bladder to ureter to kidney while voiding, usually for children with recurrent uti. It's done by injecting contrast (dye) to fill the bladder through a catheter and then take x-ray while voiding but at the time of no uti. For detailing, ask attending radiologist or urologist. Best wish ... Always. Best...