The Current Procedural Terminology (CPT) system uses standardized codes to describe medical services for billing and insurance claims. CPT Code 93975 identifies a non-invasive diagnostic test performed using sound waves. This code represents a complete duplex scan of the arterial inflow and venous outflow of the abdominal, pelvic, scrotal, and/or retroperitoneal organs. Understanding this code helps decipher the medical necessity and costs associated with this detailed vascular evaluation.
The Non-Invasive Vascular Monitoring Procedure
The procedure covered by CPT Code 93975 is a duplex scan, a type of vascular ultrasound that combines two technologies to create a complete picture of blood vessel health. The first component is B-mode ultrasound, which uses sound waves to create a two-dimensional image of the blood vessel structure and surrounding tissues. This allows the clinician to visualize the anatomy, including the vessel walls and any potential blockages or aneurysms.
The second component is Doppler technology, which measures the speed and direction of blood flow within the vessels. The Doppler signal is converted into a distinct sound and a spectral waveform, providing quantitative data on flow patterns. For the 93975 code to be reported as a complete study, the examination must fully evaluate both the arterial flow entering the target organs and the venous flow leaving them. This comprehensive assessment is applied to major vessels supplying organs such as the kidneys, ovaries, or testicles, and is commonly used to diagnose conditions like renal artery stenosis or pelvic congestion syndrome.
Why Monitoring Vascular Status is Essential
Duplex technology is also used widely in vascular surgery to monitor arterial bypass grafts. An arterial bypass graft reroutes blood flow around a blocked artery, often in the legs, using a natural vein or synthetic tube. This reconstruction is necessary for patients with severe peripheral artery disease to restore circulation and prevent complications like limb ischemia.
Routine surveillance using duplex scanning is performed after the surgery to detect early signs of graft deterioration, which may not yet be causing symptoms. The scan looks for stenosis, or narrowing, caused by cellular growth within the graft wall or a progression of disease in the native vessels. Detecting a significant narrowing allows for a minimally invasive intervention before the condition progresses to a complete occlusion, or thrombosis.
Early detection improves the long-term success, or patency, of the graft by allowing for timely, less-complex repair procedures. Surveillance protocols often involve scans at frequent intervals, such as 3, 6, and 12 months post-surgery, and then annually if the graft remains healthy. These measurements track changes in blood flow velocity, which indicates potential graft failure.
Navigating the Administrative Use of the Code
The use of CPT codes like 93975 is governed by the concept of “medical necessity,” meaning the procedure must be reasonable and necessary for the diagnosis or treatment of an illness or injury. Documentation supporting this code must clearly state the clinical reason for the complete evaluation of both arterial inflow and venous outflow in the target region. Insurance payers often have specific policies regarding how frequently a duplex scan can be repeated for monitoring a chronic condition.
When reviewing a bill for a duplex scan, the charge may be broken down into two parts: the technical component (T.C.) and the professional component (P.C.). The technical component covers the costs associated with performing the test itself, including the equipment, supplies, and the sonographer’s time. The professional component represents the physician’s fee for interpreting the images, analyzing the Doppler flow data, and issuing a formal report. These components may be billed separately or together as a global service, depending on where the procedure was performed.