When evaluating a patient for a Deep Vein Thrombosis (DVT), a venous duplex scan is performed. CPT 93970 represents a complete bilateral study of the extremity veins.
Unilateral vs Bilateral Scans
- 93970 (Complete): A full bilateral scan (both legs or both arms). Do not use Modifier 50.
- 93971 (Limited): A unilateral scan (only one leg or arm) OR a limited bilateral scan.
Medical Necessity & ICD-10 Links
Medicare requires clear signs and symptoms of DVT or venous insufficiency to justify the scan. Common approved codes include:
- M79.604 - Pain in right leg
- R60.0 - Localized edema
NCCI Edits
If the patient is coming in purely for the ultrasound (scheduled by another doctor), do not bill an E/M visit. If your physician evaluates the patient, orders the scan, and performs it all in the same visit, append Modifier 25 to the E/M.