SPECIFIC MODIFIERS FOR DISTINCT PROCEDURAL SERVICES
The primary issue associated with the -59 modifier is that it is defined for use in a wide variety of circumstances, such as to identify different encounters, different anatomic sites, and distinct services. This modifier is infrequently (and usually correctly) used to identify a separate encounter. It is less commonly (and less correctly) used to define a separate anatomic site. It is more commonly (and frequently incorrectly) used to define a distinct service.
CMS established four additional HCPCS modifiers (called -X{EPSU}) to define specific subsets of the -59 modifier:
While CMS recognizes the -59 modifier in many instances, it may selectively require a more specific -X{EPSU} modifier for billing certain codes at high risk for incorrect billing. For example, a particular NCCI PTP code pair may be identified as payable only with the -XE separate encounter modifier but not the -59 or other -X{EPSU} modifiers. The -X{EPSU} modifiers are more selective versions of the -59 modifier, so it would be incorrect to include both modifiers on the same line.
These modifiers were developed to provide greater reporting specificity in situations where modifier -59 was previously reported and may be utilized in lieu of modifier 59 whenever possible. Modifier -59 should only be utilized if no other more specific modifier is appropriate.