Flaps, revisited

Cracking the Code

Alexander Miller

Dr. Miller, who is in private practice in Yorba Linda, California, represents the American Academy of Dermatology on the AMA-CPT Advisory Committee.

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Your office bills CPT 11100 to Medicare for a diagnostic biopsy of a clinically atypical nevus. The subsequent electronic remittance reveals that you are being paid absolutely nothing for your legitimate and medically necessary service. Why is that? The answer: improper billing during the Global Surgery Period.

The Global Surgery Period for each procedure in the CPT is either zero days, 10 days, or 90 days. This means that during a zero-, 10-, or 90-day expanse following a procedure all routine visits related to the procedure, such as bandage changes, wound checks, and suture removals are included in the procedure’s valuation, as they are part of the “global surgical package,” and are not to be billed to the insurer or to the patient. However, if unrelated necessary services are done during the global surgical period, then these separately identifiable services are billable with an appropriate modifier. The commonly needed (and occasionally overlooked) modifiers for use during the global period are:

  • 24: Unrelated E/M service by the same physician or other qualified health care professional during a postoperative period
  • 25: Significant, separately identifiable E/M service by the same physician or other qualified health care professional on the same day of the procedure or other service
  • 57: Decision for surgery (refers to E/M service resulting in a decision to perform a 90-day global surgery the day of or day after the evaluation)
  • 79: Unrelated procedure or service by the same physician or other qualified health care professional during the postoperative period
  • 58: Staged or related procedure or service by the same physician or other qualified health care professional during the postoperative period
The chart documentation must adequately justify the use of any modifier during the post-operative period. Particularly in the case of modifier 24, “Unrelated E/M service,” one must clearly document that the E/M service is totally unrelated to the preceding procedure. Absent or improper modifier use is a major reason for claims rejection and non-payment. The billing staff must remain vigilant to ensure proper modifier selection, use, and corrected use in the case of claim rejection.

In order to properly determine the need for a modifier one must first decide whether a service falls within the postoperative period. A zero-day global means that any necessary services subsequent to the day of surgery may be billable without a modifier. The global period for a 10-day post-operative period includes the day of the procedure plus 10 days starting the day after the procedure. The 90-day post-operative period includes the day before surgery, the day of surgery, and 90 days after the day of surgery. The global period for any CPT code may be found on the CMS searchable Medicare Physician Fee Schedule tool. A detailed instructional guide on using the Web fee schedule and global period look-up module is provided in a Medicare Learning Network article.

The chart on this page summarizes the global periods for dermatology-relevant CPT codes.[pagebreak]

There are certain services that, when performed by the same individual who does the surgery, are included in the procedure valuation and not billed separately. These are:

  • Preoperative visits: day of surgery for 10-day global (minor) procedures and day before surgery for 90-day global (major) procedures
  • Postoperative complications not requiring a return to the operating room
  • Postoperative follow-up visits
  • Dressing changes, surgical site care, removal of sutures or staples
  • Control of postoperative hemorrhage, unless it involves a return to the operating room
  • If the decision to perform a minor (10-day global) procedure is made on the day of the procedure, it is customarily considered to be a preoperative service included in the minor procedure valuation.

View a complete description of Medicare policies relating to the Global Surgery Period, or download a shorter fact sheet. Finally, learn more about how the global period works for dermatologists in an article featured in Member to Member last year.

Now, let’s return to the vignette featured at the start of this article. Why was the biopsy, CPT 11100, not paid? The explanation: the remittance advice stated that payment for the procedure was included in the payment for a previous procedure. It turns out that the previous procedure was a destruction of several actinic keratoses done eight days earlier. Since the destruction codes have a 10-day global period, the biopsy should have been billed with a 79 modifier to specify that it was unrelated to the destruction of the actinic keratoses.[pagebreak]

Example 1: An established patient with a family history of melanoma is evaluated for a changed mole on his back. You obtain a history for the lesion, examine it and, suspecting an atypical nevus, decide to excise it on the day of the visit. You bill for the excision and CPT 99212 for the evaluation.

Answer: Incorrect. As the excision constitutes a minor, 10-day global procedure, the decision to excise the lesion is included in the procedure’s valuation. A separate E/M billing is not warranted, as only the lesion was evaluated and treated. However, if on the basis of the clinically atypical nevus a complete skin examination was done along with palpation of lymph node basins, and appropriately documented, that would have constituted a significant separately identifiable E/M service billable with a 25 modifier. Specifically for zero- and 10-day global procedures, the decision to do the procedure is included in the valuation of the procedure, and should not be billed with an E/M charge. However, if a separately identifiable E/M service beyond that resulting in the decision to do the procedure is done, then an E/M charge is acceptable. Both the procedure and the E/M charge can be referenced to one and the same diagnosis as long as a documented distinct E/M service is done (NCCI Manual, 2014).

Example 2: A patient is referred to you for Mohs surgery. You evaluate the patient, decide that Mohs surgery is appropriate, and, as you are doing Mohs surgery that day, proceed to excise the nasal tumor and repair the defect with an advancement flap. You bill 17311 for one stage of Mohs surgery and 14060 for the flap repair. In addition, you charge for the initial patient evaluation leading to the decision for surgery, CPT 99202-57.

Answer: Correct. As the visit culminated with a major surgical procedure (the flap repair) with a 90-day follow-up period the initial, same-day evaluation to determine the need for surgery with a 90-day period is billable with a 57 modifier and payable. In the above example, if a complex repair (10-day global) instead of a flap were done, an E/M charge of 99202 would not be appropriate, as the decision to do a zero- or 10-day global procedure is included in the payment for the procedure.

Example 3: You excise an atypical nevus on the chest of a patient on May 9. As the nevus turns out to be a melanoma, you promptly recall the patient and do a therapeutic wide excision on May 19. You bill for the melanoma excision with a 58 modifier appended to the excision and repair codes.

Answer: Correct. Since the second procedure was related to the first, and was done on the 10th day of the initial procedure’s 10-day post-operative period, the 58 modifier is necessary, as it distinguishes the service as related to but separate from the first excision.


Related Resources

Global periods for common dermatology codes