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  • Savvy Coder

    NCCI, Part Two: Examples of Unbundling

    By Sue Vicchrilli, COT, OCS, Academy Coding Executive, and Michael X. Repka, MD, MBA, Academy Medical Director for Governmental Affairs

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    Last month, EyeNet provided an overview of the National Correct Coding Initiative (NCCI), explaining that CMS lists pairs of services that should not be billed together when performed by the same provider on the same patient on the same day. Each pair is known as an NCCI edit. CMS identifies some edits as being “mutually exclusive,” which means they can never be paid separately. Other edits can be paid separately in certain circumstances, a process known as “unbundling.” Here are three more examples demonstrating how to unbundle NCCI edits.

    Example 1: Separate Injury

    A patient undergoes pterygium surgery in the right eye. During the 90-day global period, she is hit in the left eye with a bungee cord, causing a traumatic cataract and vitreous hemorrhage. Immediate surgery is scheduled.

    Correct coding for the exam. The appropriate level of E&M (9921X–57) or Eye code (9201X–57). 

    Use of modifier. Modifier –57 indicates that this is the exam to determine the need for surgery.  

    Correct coding for the surgery. CPT code 67036–79–LT (for the vitrectomy) and CPT code 66984–59–79–LT (for the cataract removal). 

    Use of modifiers. NCCI edits bundle 66984 with 67036. When you know preoperatively that both procedures will be performed, it is appropriate to unbundle by appending modifier –59 to 66984. Modifier –79 is used to indicate that these surgeries are unrelated to the pterygium surgery.

    Know which code to list first. The rules for the reimbursement of multiple procedures mean payment for the code that is listed first will be 100 percent of its allowable; for the code listed second, 50 percent of its allowable. Therefore, the code with the highest allowable—in this case, vitrectomy— should be listed first. 

    Example 2: Different Surgery Site

    One lesion is excised and another is biopsied, both on the right lower lid.

    Correct coding. CPT code 67810–RT (for excising an eyelid lesion, except for a chalzion, without closure or with simple direct closure) and 67810–59–RT (for the biopsy).

    Use of modifier. If you don’t append modifier –59, the insurance company would assume that the biopsy and excision involved the same lesion. 

    Example 3: Different Procedure

    For the convenience of the patient, an Nd:YAG capsulotomy is performed on the left eye the same day as cataract surgery on the right eye.

    Correct coding: CPT code 66984–RT (for the cataract removal) and CPT code 66821–59–LT (for the Nd:YAG).

    Use of modifiers: It would not be enough to just append modifiers –RT and –LT. Modifier –59 is needed to unbundle an NCCI edit. 

    Three FAQs

    Q: Blepharoplasty and ptosis surgery are bundled together. Is there ever a circumstance in which it is appropriate to unbundle with modifier –59? 

    A: Only if one procedure was performed on the left eye and the other on the right.

    Q: If we order SCODI for glaucoma and OCT for retina on the same patient on the same day, are CPT codes 92133 and 32134 both billable?

    A: Never. According to NCCI, this bundling edit is mutually exclusive.

    Q: What’s new with NCCI?

    A: NCCI is updated quarterly. The Oct. 1 changes affected more than 320 CPT codes used in eye care. View them at (click “Coding Tools” and then “CCI Edits”). 


    –57     Decision for surgery
    –59 Distinct procedural service
    –79 Unrelated procedure or service by the same physician during the postoperative period
    –LT Left side
    –RT Right side