Question: Do we need modifier -51 (Multiple procedures) with 51726 (Complex cystometrogram [e.g., calibrated electronic equipment]), 51772 (Urethral pressure profile studies [UPP] [urethral closure pressure profile], any technique), 51795 (Voiding pressure studies [VP]; bladder voiding pressure, any technique), etc? Illinois Subscriber Answer: Although urodynamic procedures are diagnostic, they are in the surgical CPT section for urology. Consequently, they must follow all rules applied to surgical codes. Urodynamic codes all have zero-day global periods. When there is a primary urodynamic procedure, you should report all subsequent urodynamic codes with modifier -51 appended. Most Medicare carriers will add modifier -51 for you. However, you should always place 51797 (Voiding pressure studies [VP]; intra-abdominal voiding pressure [AP] [rectal, gastric, intraperitoneal]) as the first procedure, when applicable, because this is the highest-paying urodynamic code. The first code will be paid in full, while all others will be reimbursed at 50 percent.
Medicare will reorder the codes as they are listed on the CMS 1500 form to ensure it pays the highest fee at 100 percent. But commercial payers will neither reorder the codes nor recognize modifier -51. Private payers limit the number of payable urodynamic services for which they will reimburse. Using modifier -51 on all other codes will indicate 51797 as your primary procedure.