Repairs following Mohs Surgery

Question:

Our Mohs surgeons will sometimes perform an adjacent tissue transfer or a flap after Mohs surgery.  They want to bill an E/M service with Modifier 57 since they decided to do the flap after Mohs.  I don’t think this is correct.  Can you help clarify?

Answer:

The E/M service should not be reported after Mohs surgery when a decision is made for a repair, flap, or graft.  Even though a flap has a 90-day global period, the surgical decision was made to perform Mohs, the primary procedure.  The intent of the E/M with Modifier 57 for a procedure with a 90 global period is when the initial decision is made to perform the primary procedure.  The repair is secondary; therefore, billing an E/M service is inappropriate.  The discussion and recommendation for the repair is part of the pre-service work for the repair.

*This response is based on the best information available as of 2/29/24.