CPT code 51797: Abdominal pressure test, urodynamic add-on measurement2026 Medicare rate & RVUs

Medicare pays $154.98 for 51797 nationally in the office. Local office rates run $136.00–$212.71.

Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.

What 51797 covers

This add-on captures intra-abdominal pressure during urodynamic evaluation, commonly through a rectal pressure catheter or balloon while bladder pressure is recorded. Comparing abdominal and bladder pressure helps the clinician assess detrusor pressure during filling and voiding. Urologists and other clinicians who perform urodynamic studies use it in office or facility settings for patients evaluated for urinary retention, incontinence, or other lower urinary tract symptoms.

Report 51797 only with a primary procedure, commonly 51728 or 51729, when the abdominal-pressure measurement is performed; it is not a stand-alone service. The record should identify the measurement method, include the pressure data, and support its role in the study. CMS treats payment for this add-on as within the primary procedure's global period. The service may be billed globally without a modifier or split between interpretation (modifier 26) and equipment and staff (modifier TC); CMS separately prices both component modifiers.

This summary was written with AI assistance from CMS physician fee schedule data and checked against the CMS billing rules shown here. Rates on this page come directly from CMS files.

Where 51797 pays more and less

The same RVUs, adjusted for each area’s costs. Open a locality for its calculation, history and nearby areas.

109 of 109 payment localities

51797 rates by state

Office rate range in each state. Select a state to see its payment localities.

How the 51797 rate is calculated

Each of 51797’s three RVUs is multiplied by a geographic index (GPCI) for the payment locality, added up, and multiplied by the conversion factor. Drag the indexes or enter a ZIP to see what moves the rate.

Payment rules and modifiers for 51797

The CMS indicators that decide how 51797 is paid alongside other services.

What modifiers do to the payment

When to use modifier 26

51797 compared with similar codes

How to choose

51728Urodynamic studyWith voiding pressure

51728 reports the complex cystometrogram with voiding pressure studies; 51797 separately identifies the intra-abdominal pressure measurement as an add-on when performed.

51729Urodynamic studyVoiding and urethral pressures

51729 is the primary complex cystometrogram code when leak point pressure studies are included. 51797 reports the intra-abdominal pressure measurement alongside the primary study.

51726CystometrogramElectronic pressure-volume testing

51726 reports a complex cystometrogram without the voiding pressure study focus of 51728. 51797 is an add-on measurement, not a substitute for the primary cystometrogram code.

Codes related to 51797

Related codes aren’t interchangeable: bill the code that matches the service performed.

Where these rates come from

FeeBase calculates base physician payments from CMS work, practice-expense and malpractice RVUs, adjusted by each locality’s geographic indexes and the conversion factor. Services without a published rate are labeled, never given a made-up amount. Amounts are Medicare allowed amounts before claim adjustments: not a patient’s bill or a commercial rate.

CMS RVU26D · effective Oct 1, 2026 through the day before Jan 1, 2027

Open CMS sourceHow we calculate rates