HOW TO SELECT CODE AND BILL FOR DUPLEX SCAN OF EXTREMITY VEINS:
To determine a level of diagnostic CPT for veins for reporting it is necessary to know that how many vessels were imaged if the service is unilateral or bilateral, and where both the deep and superficial systems dealt with.
”The golden rule is only performed what is necessary, and only report what you performed.”
On duplex scan CPT codes 93970 and 93971, the distinction is greater than just unilateral or bilateral. 93970 is defined as a complete bilateral study, and as such must meet this definition exactly to be reported. 93971 is a unilateral or limited study and can be used for a limited bilateral service as well as a unilateral.
Medicare of FL has added a clear definition to their LCD that states:
“For a complete examination, all deep veins of the leg are examined, including the common femoral, femoral, deep femoral, popliteal, peroneal, soleal, gastrocnemial, anterior, and posterior tibial veins. The superficial veins are then evaluated including the GSV, the SSV, the accessory saphenous veins, perforating veins, and tributary veins. Six components that should be included in a complete duplex scanning examination for CVD are (1) visibility, (2) compressibility, (3) venous flow, including measurement of the duration of reflux, (4) augmentation, (5) phasicity, and (6) vein size. The cutoff value of 500 ms is for the saphenous, tibial, deep femoral, and perforating vein incompetence, and 1 second for femoral and popliteal vein incompetence.”
If even one element is left out, or not addressed in the interpretation, then the study is not complete and has to be reported with 93971 that brings us to medical necessity. Correct coding guidelines of Medicare indicate that CPT code 93971 should be used to report either a limited bilateral or a complete unilateral study (only one service should be reported). It would not be appropriate to report an -50 modifier with CPT 93971 for a limited bilateral study.
How to bill duplex scan for both upper and lower extremities:
In case a complete or limited bilateral study is done on both the upper and the lower extremities, the corresponding code can be reported once for each study performed (i.e., once for the upper extremities and once for the lower extremities). Providers should append modifier 76, repeat service by the same provider, or modifier 77, repeat service by another provider, to the second code to indicate that two separate, distinct studies were performed. There should be a separate written report/interpretation for each study performed.
NOTE: When spectral and color Doppler evaluation of the extremities is performed, use the appropriate code (93925-93926, 93930-93931, 93970, or 93971) in conjunction with 76881 or 76882.