Reason Code 54NCD
It has been determined the units of service are in excess of the Medically reasonable daily allowable frequency for HCPCS with a MAI of three. The excess charges due to units of service greater than the maximum allowable may not be billed to the beneficiary.
Go to the CMS Medically Unlikely Edits webpage. Access the National Correct Coding Initiative (NCCI)Facility Outpatient Hospital Services MUE Table and locate the HCPCS you are reporting on the claim to determine how many units are allowed per day.
Medically Unlikely Edits (MUE) CMS website