Make Modifiers Matter

By Linda R. Farrington, CPC, CPC-I

A thorough understanding of modifiers is essential to accurate coding and reimbursement. To illustrate this, let’s look at a few examples of how common surgical modifiers are used.

Example 1: A patient is admitted to the hospital on Monday and undergoes right carotid endarterectomy. A left endarterectomy is planned for two days later. Documentation for the follow-up procedures states:

Postoperative Diagnosis: Bilateral severe carotid occlusive disease, status post right carotid endarterectomy.

Operative Procedure: Staged left carotid endarterectomy.

The documented procedure is reported 35301-58-LT Thromboendarterectomy, including patch graft, if performed; carotid, vertebral, subclavian, by neck incision-Staged or related procedure or service by the same physician during the postoperative period-Left side.

By appending modifier 58, you tell the payer that this is a planned, staged procedure. According to the Medicare Claims Processing Manual, you also may use modifier 58 to describe a subsequent procedure during a post-op period that is “more extensive than the original procedure.” When you apply modifier 58, a new post-op period begins and the reimbursement is based on 100 percent of the relative value unit (RVU).

Example 2: A gunshot victim has wounds to an artery and a vein of the same leg. One vessel is repaired directly. The other vessel requires a graft.

Postoperative Diagnosis: Gunshot wound with injury to popliteal artery and popliteal vein of right leg

Operative Procedure:

1. Repair of popliteal artery with GORE-TEX® graft

2. Direct repair of popliteal vein

Proper coding is 35286-RT Repair blood vessel with graft other than vein; lower extremity-Right side, and 35226-59-RT Repair blood vessel, direct; lower extremity-Distinct procedural service-Right side.

The diagnoses will differ for each procedure because there are specific injury codes for each vessel. In this case, however, the reported CPT® codes describe “mutually exclusive” procedures, according to the National Correct Coding Initiative (NCCI) at Modifier 59 may be applied by the same provider, on the same patient and date of service, to describe a different session, different procedure/surgery, different site/organ system, separate incision/excision, separate lesion or—as in this case—a separate injury (or area of injury in multiple injuries). Multiple surgery rules still apply (payment for the second procedure will be reduced by 50 percent), but without modifier 59 one of the procedures would be denied completely.

Modifier 59 is commonly misused and is often an audit target. As explained by Modifier -59 Article & General Correct Coding Policies, chapter I.E, pages I-15: “Modifier -59 is an important NCCI-associated modifier that is often used incorrectly. For the NCCI its primary purpose is to indicate that two or more procedures are performed at different anatomic sites or different patient encounters. It should only be used if no other modifier more appropriately describes the relationships of the two or more procedure codes.”

Example 3: Patient presents to the emergency department (ED) during an acute myocardial infarction. He is taken to the operating room (OR) urgently for triple vessel coronary artery bypass grafting (CABG). During the hospital stay, a large abdominal aortic aneurysm (AAA) is discovered. The aneurysm is repaired two months later (within the global period of the CABG). Documentation for the AAA repair states:

Postoperative Diagnosis: Infrarenal abdominal aortic aneurysm.

Operative Procedure: Resection, infrarenal abdominal aortic aneurysm (18-mm Dacron tube graft).

Proper coding is 35081-79 Direct repair of aneurysm, pseudoaneurysm, or excision (partial or total) and graft insertion, with or without patch graft; for aneurysm, pseudoaneurysm, and associated occlusive disease, abdominal aorta-Unrelated procedure or service by the same physician during the post operative period.

By appending modifier 79, you tell the payer that—although this procedure was performed during the post-op period of another procedure—the AAA repair is completely unrelated to the procedure that preceded it. Claims filed with modifier 79 are excluded from prepayment audit. A new post-op period begins and payment is based on 100 percent of the RVU. If you were to bill this procedure without a modifier, the claim would be denied.

Compare modifier 79 with modifier 78 Unplanned return to the operating/procedure room by the same physician following initial procedure for a related procedure during the postoperative period. The Medicare Claims Processing Manual defines an operating/procedure room as “a place of service specifically equipped and staffed for the sole purpose of performing procedures. The term includes a cardiac catheterization suite, a laser suite, and an endoscopy suite. It does not include a patient’s room, a minor treatment room, a recovery room, or an intensive care unit (unless the patient’s condition was so critical there would be insufficient time for transportation to an OR).”

Claims submitted with modifier 78 are excluded from prepayment audit. Only the intra-operative portion of the procedure is paid. If the procedure reported has no global days, the reimbursement is based on 100 percent of the RVU. These values―the intra-operative portion and the global days―can be found by reviewing the Medicare Physician Fee Schedule (, under the columns titled “INTRA OP” and “GLOB DAYS,” respectively. If the CPT® code describes a procedure with no global days, the reimbursement is based on 100 percent of the allowed amount. By contrast, a procedure billed without modifier 58, 78, or 79 during a postoperative period of another procedure by the same provider will be denied.

The correct and judicious use of modifiers can reap significant financial rewards. For a more in-depth look at modifiers, register to attend “Modifiers: The Rest of the Story” at


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One Response to “Make Modifiers Matter”

  1. denise says:

    Is a modifier 26 required for CPT 88141to report the professional charge?

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