Radiology Coding Alert

Don't miss the significance of the ABI 'plus' requirement.

Even veteran coders can get lost reading through the code definitions for 93922 and 93923. Get on your way to deciphering these codes with the answers to three frequently asked questions.

Start here: Codes 93922 and 93923 fall under the category of noninvasive physiological studies, or NIPS, explains Cheryl A. Schad, BA Ed, CPC, ACS-RA, PCS, of Schad Medical Management in her AudioEducator.com presentation, "Understanding the Intricacies of Ultrasound Coding."

CPT® defines the codes as follows:

• 93922, Limited bilateral noninvasive physiologic studies of upper or lower extremity arteries, (e.g., for lower extremity: ankle/brachial indices at distal posterior tibial and anterior tibial/dorsalis pedis arteries plus bidirectional, Doppler waveform recording and analysis at 1-2 levels, or ankle/brachial indices at distal posterior tibial and anterior tibial/dorsalis pedis arteries plus volume plethysmography at 1-2 levels, or ankle/brachial indices at distal posterior tibial and anterior tibial/dorsalis pedis arteries with transcutaneous oxygen tension measurements at 1-2 levels)
• 93923, Complete bilateral noninvasive physiologic studies of upper or lower extremity arteries, 3 or more levels (e.g., for lower extremity: ankle/brachial indices at distal posterior tibial and anterior tibial/dorsalis pedis arteries plus segmental blood pressure measurements with bidirectional Doppler waveform recording and analysis, at 3 or more levels, or ankle/brachial indices at distal posterior tibial and anterior tibial/dorsalis pedis arteries plus segmental volume plethysmography at 3 or more levels), or ankle/brachial indices at distal posterior tibial and anterior tibial/dorsalis pedis arteries plus segmental transcutaneous oxygen tension measurements at 3 or more levels, or single level study with provocative functional maneuvers (e.g., measurements with postural provocative tests, or measurements with reactive hyperemia).

1. What Are the Different Levels?

Proper coding for 93922 and 93923 depends on precise understanding of the term "levels." The definition of 93922 (limited) specifies "1-2 levels." Code 93923's definition states "3 or more levels, or single level study with provocative functional maneuvers."

The wording raises the question of what exactly a "level" is. To be sure you count correctly, review CPT® guidelines for these codes. For a shortcut, check out this chart provided by Sean P. Roddy, MD, FACS, AMA CPT® Advisory Committee member, and Gary R. Seabrook, MD, FACS, AMA/Specialty Society Relative Value Scale Update Committee (RUC) Advisory Committee member, in their CPT® and RBRVS 2011 Annual Symposium presentation (www.ama-assn.org/resources/doc/cpt/vascular.pdf):

Bonus tip: The 93923 definition refers to "segmental" measurements. In the context of these codes, think of segmental as referring to different segments or levels. Providers may refer to the devices involved as segmental machines.

2. How Can I Be Sure My Reporting Is Compliant?

One reason 93922 and 93923 have such long code definitions is that the coding powers-that-be saw an excessive growth in 93922 use and were concerned the code was being reported inappropriately for ankle/brachial indices (ABI), Schad explains. The long definitions were created to clarify the minimum service requirements for each code. To code correctly, you need to understand what an ABI is, which services qualify for 93922 or 93923, and which services you should include under E/M.

ABI: ABI involves using a Doppler ultrasound stethoscope to measure sound within the vessels at the ankle and elbow while inflating cuffs placed on the arms and legs. The tester divides the arm measurement by the ankle measurement. A result under 1 may point to artery blockage in the legs.

ABI plus: ABI alone does not qualify for 93922 or 93923. CPT® guidelines state that you may report ABI using those codes only when there is "simultaneous Doppler recording and analysis of bidirectional blood flow, volume plethysmography, or transcutaneous oxygen tension measurements." So you shouldn't report 93922 or 93923 unless documentation shows ABI plus one of those other tests.

E/M: The guidelines list two services you should include as part of the E/M vascular physical exam instead of using 93922 or 93923. Keep an eye out for use of a hand-held or other Doppler device that:

• Doesn't allow the creation of hardcopy output (keep in mind that for these studies you'll see measurements and charts rather than imaging)
• Produces a record that doesn't allow analysis of bidirectional vascular flow (for instance, the device can detect flow, but it can't determine the direction of the flow).

3. What Are the Specific NIPS Listed?

The code definitions list the following exams:

• ABI
• Bidirectional Doppler waveform recording and analysis
• Volume plethysmography
• Transcutaneous oxygen measurements.

Question 2 discussed ABI services. Read on for more information on the other exams.

Bidirectional Doppler waveform analysis: Doppler ultrasound involves evaluating blood flow using reflected sound waves. If the cells are in motion, the sound changes. But the pitch doesn't change if there's no blood flow. As a result, the physician can measure Doppler velocity signals, also called waveforms, to locate vascular disease, according to The ACR Radiology Coding Source (January/February 2007).

Plethysmography: When the physician measures an organ or limb section's volume or flow rate, this is plethysmography. In other words, the test determines circulatory capacity of arteries, Schad says. Different types include air, impedance, strain gauge, and photo, CPT® Assistant (August 2009) states. For instance, you may see a pulsed volume recorder (PVR) for segmental air plethysmography using cuff pressure. Or for strain gauge plethysmography, staff members place an "elastic tube filled with an electro-conductive metal" around the patient's limb and evaluate blood flow based on the volume changes revealed by the specialized tube, states CPT® Assistant.

TCOM: Transcutaneous oxygen tension measurement may be abbreviated as TCOM, Schad notes. You also may see the term TcPO₂. This service involves placing electrodes or sensors on the skin to identify the amount of oxygen carried to the skin by the arteries, explains Schad. This knowledge is important to the treating physician's medical decision making, she says. For instance, it may help in deciding the course for wound care for diabetic patients.