As a rule, we cannot bill for procedures provided at the same anatomic site at the same patient encounter. So, what about when you do need to indicate that a procedure or service is distinct or independent from another service performed on the same day?

Use modifier -59, which is applied to identify procedure(s) and service(s) that are not normally reported together, but are appropriate under the circumstances. This may represent a different session or patient encounter, different procedure or surgery, different site or organ system, separate incision/ excision, separate lesion, or separate injury not ordinarily encountered or performed on the same day by the same physician.

A Dangerous Proposition

However, as I have discussed many times over the years, the routine use of modifier -59 is a very dangerous proposition. Here's why:

  • The -59 modifier is the most widely used modifier, according to the Centers for Medicare & Medicaid Services (CMS). Because it can be so broadly applied, it's associated with considerable abuse and high levels of manual audit activity, leading to reviews, appeals and even civil fraud and abuse cases.
  • Some providers incorrectly consider it to be the modifier to use to bypass the National Correct Coding Initiative (NCCI). So it's the number one modifier to attract the attention of third-party carriers. Keep in mind that modifier -59 can only bypass edits when:
  • A combination of procedure codes represent procedures that wouldn't normally be performed at the same time (e.g., a procedure on the head and a procedure on the feet).
  • A different session or patient encounter is documented in patient's medical record.
  • Surgical procedures performed are not done through the same incisional site.
  • Another modifier is not as appropriate (e.g., modifier -51).
  • It's used as a modifier of last resort.

But last year, CMS indicated that modifier -59 is the appropriate modifier to use in the very rare circumstances when performing fundus photography (92250) and OCT of the posterior segment (92134) on the same date of service, assuming you've met the rules of medical necessity.

Generation X

Accordingly, more precise coding options are needed to reduce improper use of the -59 modifier. To that end, CMS has established four new Healthcare Common Procedure Coding System (HCPCS) modifiers to selectively define subsets of the -59 modifier, used to designate a distinct procedural services.

These modifiers, collectively referred to as -X{EPSU} modifiers, will be implemented January 5, 2015. They define specific subsets of the -59 modifier:

XE—Separate Encounter: A service that is distinct because it occurred during a separate encounter.

XS—Separate Structure: A service that is distinct because it was performed on a separate organ/ structure.

XP—Separate Practitioner: A service that is distinct because it was performed by a different practitioner.

XU—Unusual Non-Overlapping Service: The use of a service that is distinct because it does not overlap usual components of the main service.

Initially, either modifier -59 or a more selective -X{EPSU} modifier will be accepted, but notes that the -59 modifier should not be used when a more descriptive modifier is available. CMS may selectively require a more specific -X{EPSU} modifier for billing certain codes at high risk for incorrect billing.

At the time of this writing, more specific rules and clinical application of the X modifiers have not been released. I'm hopeful that within the coming weeks, we'll have further clarification from CMS regarding the use of the X modifiers to continue to allow us to perform OCT and fundus photography on the same day of service when dictated by clinical circumstances.

Until then, please be aware of this change and be very judicious in your use of -59 in 2015.

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