ICD-10 Coding for Soft Tissue Radiation Necrosis Treated with HBOT

There have been many challenges for everyone in the health care profession related to the implementation of ICD-10, which took effect on October 1, 2015. Fortunately, the field of hyperbaric medicine had a very short list of covered indications to crosswalk from ICD-9 to ICD-10 in comparison with other specialties. Of that short list, soft tissue radiation necrosis has proven to be quite problematic. If you look for diagnosis codes in ICD-10 based upon the term “soft tissue radiation necrosis,” the only code that returns is M27.2 inflammatory conditions of the jaw. This is an accurate representation of osteoradiation necrosis of the jaw, however, not for soft tissue radiation necrosis. 

Trying to tell someone how to code claims for soft tissue radiation necrosis is not, therefore, a straightforward task. Under ICD-9, the local coverage determinations (LCDs) had selected 909.2 (late effect of radiation) or 990 (effects of radiation not otherwise specified) to represent this condition. It made sense to document soft tissue radiation damage as late effects of radiation since that was indeed what the patient was experiencing. Whether you were manually coding claims from an ICD-9 book or using coding software, this diagnostic statement resulted in consistent diagnostic codes for both government and commercial payors.

With the implementation of ICD-10, the Medicare national and local coverage documents (national coverage determinations [NCDs] and LCDs) required General Equivalence Mapping to crosswalk the ICD-9 codes to the updated ICD-10 codes. This resulted in ICD-9 code 990 crosswalking to T66.XXXA radiation sickness, unspecified, initial encounter and ICD-9 code 909.2 crosswalking to L59.9, disorder of the skin and subcutaneous tissue due to radiation, unspecified.

The ICD-10 code T66.XXXA never truly represented the indication for which hyperbaric oxygen therapy (HBOT) was being provided, because soft tissue radiation necrosis is not generally the same as radiation sickness. Additionally, if you examine the “exclude 1” note within the ICD-10 Coding Manual, it specifically excludes the L55-L59 range of diagnoses, which refer to skin and subcutaneous conditions related to radiation. The Centers for Medicare and Medicaid Services (CMS) removed this diagnostic code from the NCD in change request CR9252, which was revised on December 3, 2015, and had an implementation date of January 4, 2016. This left the CMS NCD with only L59.9 on the list of covered diagnoses representing soft tissue radiation necrosis. This code related to soft tissue radiation injury, but the descriptor also indicated it was unspecified. This meant that when providers documented the specific area of radiation injury, this was not the correct code to use based upon coding conventions, but the use of any other code likely resulted in a claim denial. Although some wound management revenue cycle teams chose to submit a more specific code according to coding conventions and then appeal the denial, others just submitted the claim with the less specific code, agreeing it was not the correct one but avoiding potential tie-ups.

 In 2017, the list of covered indications in the NCD was updated again, and CMS instructed Medicare Administrative Contractors (MACs) to remove ICD-10 diagnosis code L59.9 from the NCD and replace it with L59.8 (other specified disorders of the skin and subcutaneous tissue related to radiation) to represent soft tissue radiation necrosis going forward. This at least removed the unspecified language from the diagnostic code chosen, allowing for more compliant coding as the specific area of injury was most certainly documented in the medical record. 

The update by CMS in 2018 resulted in L59.9 being added back in to the NCD list of covered diagnoses, and, going into 2019, both L59.8 and L59.9 are covered diagnosis codes for soft tissue radionecrosis. While the NCD indicates both of these conditions are single diagnostic codes, meaning no other code is required to be used along with them, not all MACs share this opinion. Numerous MACs that accept all soft tissue radiation necrosis diagnoses require dual diagnostic coding. This means they require a code to represent the anatomical location of radiation damage and then an additional code to represent the soft tissue radiation  necrosis.

Payors appear to agree that soft tissue is anything that is not bone, but there seems to be a disconnect between that thought and what is acceptable in the actual coding and documentation for soft tissue radiation necrosis for sites other than the bladder. For example, if the patient has radiation proctitis, if any term other than soft tissue radiation necrosis of the rectum is documented and any ICD-10 code other than L59.8 is reported on the claim, payment will likely be denied for failure to have a covered indication. This is despite the rectum clearly being “soft tissue,” even according to the payors.

To further complicate things, commercial payors vary greatly in the codes they recognize. For example, certain commercial payors recognize T66.XXXA, another group recognizes M79.9 soft tissue disorder unspecified, and even more may recognize Z92.3 personal history of irradiation.    

In summary, with all of the diagnostic codes gained in ICD-10, soft tissue radiation necrosis is one condition that did not get represented well. Because of that, there is currently little consistency from a coding perspective to represent this condition. The disparity has resulted in an increased number of denials for HBOT claims. 

Coding and billing specialists for the wound clinic revenue cycle team can follow several steps to mitigate HBOT claim denials related to soft tissue radiation necrosis. Be sure to:

• Clearly document that the patient is being treated for soft tissue radiation necrosis and the specific anatomical site;
• Always verify the ICD-10 code for non-Medicare patients prior to starting their treatment;
• Make sure changes to NCDs and LCDs are followed so that approved codes are kept current;
• Check that the documented diagnostic statement is consistent with the ICD-10 code submitted on the claim; and
• Perform claim audits to ensure no denials occurred, especially because use of specific codes does not guarantee payment.

If a claim is denied even though the appropriate medical necessity has been documented, take the time to submit an appeal for payment. 

Valerie Short is Director of Operations and Compliance of National Baromedical Services in Columbia, SC.