By Cyber Sense Billing Team · Published · Updated
Why global periods matter so much in dermatology
Dermatology practices perform a large volume of minor procedures: biopsies, excisions, destructions, repairs, and Mohs surgery. Under the Medicare physician fee schedule, each surgical code carries a global period that bundles certain related services into the procedure payment. Most minor dermatology procedures have a 0-day or 10-day global period, while some larger procedures carry 90 days. Because patients often return several times for suture removal, wound checks, new lesions, and unrelated chronic conditions, a practice can easily either bill visits that are already included or fail to bill visits that are separately payable. Accurate global period tracking addresses both risks.
What a global period includes
CMS describes the global surgical package as including preoperative visits after the decision for surgery (the day before and day of surgery for major procedures), the procedure itself, routine postoperative care such as dressing changes, suture removal, and wound checks, and treatment of postoperative complications that do not require a return to the operating room. For 0-day and 10-day procedures, an E/M visit on the same day is generally included unless it is significant and separately identifiable. Commercial payers often follow similar global periods but may publish their own values, so practices should confirm payer-specific rules for the procedures they perform most.
Knowing the global period for each code
The global days for each CPT code are published in the Medicare physician fee schedule relative value file, in a field labeled with values such as 000, 010, 090, or indicators such as XXX for codes where global concepts do not apply and ZZZ for add-on codes. A simple reference list of the practice's top procedures and their global days, updated each year, prevents guesswork. Many practice management systems can flag a patient who is inside a global period when a new visit is scheduled, but that flag only works if the procedure codes and dates are entered accurately.
Modifier 24: unrelated E/M during the postoperative period
When a patient inside a 10-day or 90-day global period is seen for a problem unrelated to the procedure, such as a new suspicious lesion on a different site or a flare of psoriasis after a basal cell excision, the E/M can be reported with modifier 24. Documentation should make it obvious that the visit addressed a different problem, ideally with a diagnosis that differs from the surgical diagnosis. Using modifier 24 for routine wound checks or suture removal related to the procedure is a frequent error that payers recoup.
Modifiers 58, 78, and 79 for additional procedures
Additional procedures during a global period need their own modifiers. Modifier 58 applies to a staged or related procedure that was planned at the time of the first procedure, more extensive than the original, or therapy following a diagnostic procedure, such as an excision after a biopsy confirmed malignancy. Modifier 78 applies to an unplanned return to the operating or procedure room for a related problem, such as a complication requiring surgical treatment. Modifier 79 applies to an unrelated procedure during the postoperative period, such as a biopsy of a different lesion. Each modifier affects whether a new global period starts, so choosing correctly also keeps future visit billing accurate.
Same-day E/M and modifier 25
On the day of a minor procedure, the decision to perform the procedure is generally included in it. A separate E/M may be supported when the dermatologist evaluates and manages problems beyond the procedure, such as treating acne and also biopsying a pigmented lesion. Modifier 25 is appended to the E/M in those cases. The note should separate the procedure documentation from the evaluation of other problems so a reviewer can see two distinct services.
Building a global period workflow
A reliable workflow assigns responsibility at each step. When a procedure is posted, the global end date is calculated and visible to schedulers and billers. When a patient in a global period is checked in, the visit reason is reviewed: related follow-up is posted as a no-charge postoperative visit, often with code 99024 for internal tracking, while unrelated problems are documented and coded with modifier 24. When an additional procedure is performed, the coder chooses among 58, 78, and 79 based on the note. Monthly reports of modifier 24 and 79 usage by provider help identify patterns that need education before a payer notices them.
Frequently asked questions
Is a biopsy follow-up visit billable?
If the visit is routine postoperative care for a biopsy with a 0-day global, follow-up on later days is generally separately reportable, while visits within a 10-day global for related care are included. Check the global days for the specific code.
When should we use 99024?
Code 99024 is used to record a postoperative visit included in the global package. It has no payment value but helps track care and is requested by some payers.
Does modifier 58 start a new global period?
Yes. A procedure reported with modifier 58 starts its own global period, which is why accurate modifier choice affects later visit billing.
Do commercial payers use the same global periods?
Many follow Medicare global days, but some publish their own. Confirm for the procedures you perform most often.
Sources and further reading
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This article is general information, not legal or coding advice. Always check current CPT®, ICD-10-CM, CMS and payer guidance. Questions? Contact us.