By Dirk Elston, MD, July 01, 2011
What’s the difference between modifiers 58, 59, and 79?
Modifier 59 ensures appropriate payment for distinct and independent services performed by the same provider on a single date of service. It should be appended to any pair of codes that would otherwise be bundled through CCI edits (see the May Cracking the Code column on CCI edits). The procedures usually involve distinct anatomic lesions. Modifier 79 ensures appropriate payment for distinct and independent services performed during a global period. A 10-day global period begins at midnight after the procedure was performed, so a separate distinct procedure performed prior to midnight would be reported with the 59 modifier. A separate and distinct procedure performed during the following 10 days would be reported using the 79 modifier.
Note that modifier 79 is only used in conjunction with procedures, never with evaluation and management codes. A 24 modifier would be appended to any distinct and separately payable evaluation and management (E/M) services during the global period.
Modifier 58 was updated in the 2008 AMA/CPT Manual as a “staged or related procedure or service by the same physician during the postoperative period.” It is used to indicate that a procedure or service performed during a postoperative period was planned or staged; more extensive than the original procedure; or for therapy following the surgical procedure. Its use will bypass CCI edits. Modifier 58 is also used for re-excisions for positive margins during a global period.
A separate distinct procedure performed during the global period would be reported along with the 79 modifier, but there has been conflicting guidance regarding what modifier to use for a second procedure on the same date of service. While a 90-day global period technically begins prior to the procedure, CPT directives advise the physician to use modifier 59 for a biopsy done on the same day as Mohs, and this rule is applied even if a 90-day global procedure (such as adjacent tissue transfer) is performed on the same date of service. (The 90-day global period begins at midnight before a procedure is performed, as these were originally assumed to be typically performed in in-patient settings with all services bundled on the day of admission.) In my experience, most carriers have accepted 59 as the appropriate modifier.[pagebreak]
Examples of the proper use of procedure modifiers:
Example 1: Use modifier 59
You perform Mohs surgery on a nasal basal cell carcinoma and close the defect with an adjacent tissue transfer (ATT). On the same day, you biopsy a large suspected lentigo maligna on the cheek. Mohs has a zero-day global period, but the adjacent tissue transfer has a 90-day global period. To avoid inappropriate bundling of the biopsy, you should append a modifier to the biopsy. As noted above, CPT and CMS suggest the use of the 59 modifier when a frozen section biopsy is done and interpreted prior to Mohs. AAD coding staff members believe that 59 would also be appropriate for a biopsy of a separate and discrete lesion on the same date of service as a 90-day global procedure.
Example 2: Use modifier 79
You perform Mohs surgery for a basal cell carcinoma, and close the defect with an ATT. Seven days later, the patient presents with presumed erythema multiforme and requires a skin biopsy. Append modifier 79 to the biopsy.
Example 3: Use modifier 58
You excise a basal cell carcinoma and the wound requires an intermediate closure. The pathologist indicates a positive lateral margin, and the patient returns five days later for a wider excision of the site. In this case, modifier 58 would be more appropriate to indicate staged excision for a positive margin. Modifier 58 is also used for staged excisions planned in advance.
Example 4: Do not use any modifier
You perform Mohs surgery on a nasal basal cell carcinoma and close the defect with an adjacent tissue transfer. Seven days later, sutures are removed. The suture removal is a component of the original procedure and should not be billed or reported separately.