Current Procedural Terminology (CPT) codes are a standardized numerical language used for reporting medical services and procedures to payers like insurance companies. CPT 93970 is a specific code referring to a non-invasive diagnostic procedure used to evaluate the vascular system. This code identifies a comprehensive examination focused on the veins of the extremities, providing details about blood flow and vessel health.
Understanding the CPT 93970 Description
The full description for CPT 93970 is “Duplex scan of extremity veins including responses to compression and other maneuvers; complete bilateral study.” This code designates a specific type of non-invasive ultrasound that examines the veins in both the patient’s limbs, typically the legs, in a single session. The term “Duplex” indicates that the procedure combines two technologies: traditional B-mode ultrasound and Doppler ultrasound.
The B-mode component creates real-time images of the vein’s structure, allowing the technologist to visualize the vessel walls and any internal abnormalities, such as blood clots. The Doppler component uses sound waves to measure the speed and direction of blood flow within the veins. Combining these two elements provides a complete assessment of both the anatomy and the function of the venous system. Crucially, the code specifies a “complete bilateral study,” meaning a comprehensive examination of all major deep and superficial veins in both extremities.
Conditions Requiring This Examination
A physician orders CPT 93970 when a patient presents with symptoms suggesting a problem with blood return in their limbs. The primary necessity for this examination is the diagnosis or exclusion of Deep Vein Thrombosis (DVT). DVT involves a blood clot forming within a deep vein, which can cause symptoms like unexplained swelling, pain, or redness in the extremity.
This duplex scan is also used to evaluate Chronic Venous Insufficiency (CVI), a condition where damaged vein valves allow blood to flow backward, known as reflux. The “responses to compression and other maneuvers” mentioned in the code are performed during the scan to provoke and measure this reflux, helping determine CVI severity. Other indications include evaluating symptomatic varicose veins and assessing for post-thrombotic syndrome after a previous DVT.
What to Expect During the Duplex Scan
The Duplex Scan is non-invasive, involving no needles, injections, or radiation. The patient typically lies on an examination table while the vascular technologist applies a water-based gel to the skin of the extremity. This gel helps transmit the sound waves from the transducer into the body.
The technologist presses the handheld transducer lightly against the skin and moves it across the path of the veins. During the scan, the patient may be asked to perform breathing exercises, such as the Valsalva maneuver, or the technologist may apply brief external compressions to the limb. These actions are the “other maneuvers” referenced in the CPT code description, performed to evaluate the responsiveness of the vein walls and the competence of the valves. A complete bilateral study generally takes between 30 and 60 minutes to perform.
Billing Considerations for CPT 93970
Accurate medical billing for CPT 93970 hinges on the distinction between a complete bilateral study and a more limited examination. Since the code represents a “complete bilateral study,” it is only appropriate when the major deep and superficial veins of both extremities have been fully assessed. If only one extremity is examined, or if the examination is limited in scope, the corresponding code CPT 93971 (“unilateral or limited study”) must be used instead.
Proper documentation of medical necessity is required, necessitating the patient’s medical record to clearly state the symptoms or condition that necessitated the full bilateral assessment. The total charge for the scan may be broken down into two components: the technical component (-TC) covers the equipment, supplies, and technologist’s time, while the professional component (-26) covers the physician’s interpretation and report of the findings. If a provider performs bilateral upper and lower extremity scans on the same day, a modifier may be required to indicate that the two services were performed on distinct body areas.