You should append modifier 58, Staged or related procedure or service by the same physician or other qualified healthcare professional during the postoperative period, only during the postoperative period of a prior procedure, to indicate that the present procedure meets one (or more) of the following three conditions:
1. Present procedure was planned prospectively, or at the time of the prior procedure.
CPT Assistant (February 2008) clarifies, "Decisions to perform subsequent procedure(s) may depend on the outcome of the surgery and the patient's postoperative status."
For example, skin grafts may be performed in stages to allow adequate healing time between procedures. Subsequent skin grafts are expected, following initial procedure, and therefore may be reported during the postoperative period of a previous graft with modifier 58 appended.
Do not append modifier 58 if the code descriptor specifies "one or more visits" or "one or more sessions" (e.g., 66762 Iridoplasty by photocoagulation (1 or more sessions) (e.g., for improvement of vision, for widening of anterior chamber angle))
2. Present procedure is more extensive than the prior procedure.
Although the present procedure must "go beyond" the initial procedure, it is performed for the patient's underlying condition, rather than due to a complication of the prior procedure.
Note, also, that "more extensive" does not mean that procedure to which you append modifier 58 must be more complex or time-intensive than the original procedure (although, it may be). Rather, the present procedure must "extend" the work performed during the previous procedure.
The American Urological Association provides an excellent example on its website:
"An example would be if a patient has been treated for ureteral stones by extracorporeal shock wave lithotripsy with ureteral stent placement. Along with the physician's procedural dictation, he or she adds in the operative note that the patient will come back to the office within 7-10 days to have the stent removed. When the patient presents in the office for stent removal, a 52310 Cystourethroscopy, with removal of ureteral stent with modifier 58 can be billed out."
In this case, the "follow up" procedure is both planned prospectively and more extensive to the original procedure.
3. Therapy following a diagnostic surgical procedure
For example, the General Correct Coding Policies for National Correct Coding Initiative Policy Manual for Medicare Services, Chapter 1, explains:
"If a diagnostic endoscopy is the basis for and precedes an open procedure, the diagnostic endoscopy is separately reportable with modifier 58. However, the medical record must document the medical reasonableness and necessity for the diagnostic endoscopy."
In this case, the open procedure is a therapeutic procedure following a diagnostic endoscopy.
In another example, a patient may have a surgical breast biopsy, and if the pathology report indicates that the specimen is malignant, the patient may elect to have an immediate radical mastectomy. A new postoperative period would start after the mastectomy, and any postoperative care provided to the patient would be part of the surgical package for the mastectomy.
Note that there's no requirement that the patient return to the operating room to use modifier 58; however, CPT Assistant (Feb 2008) advises, "The Centers for Medicare and Medicaid Services (CMS) and most other payers do not accept modifier 58 with any procedures having a global surgical period of zero days."
Do not use modifier 58 if the patient needs a follow-up procedure because of surgical complications or unexpected postoperative findings that arise from the initial surgery.
Turn to modifier 78 for complications of surgery
For example, a return to the operating room to control bleeding is "more extensive" than the original procedure, but occurs due to complication of the initial procedure, rather than as further treatment for the underlying condition. The General Correct Coding Policies for National Correct Coding Initiative Policy Manual for Medicare Services, Chapter 1, elaborates:
"Control of postoperative hemorrhage is … not separately reportable unless the patient must be returned to the operating room for treatment. In the latter case, the control of hemorrhage may be separately reportable with modifier 78.
"When treatment for complications requires a return to the operating or procedure room append modifier 78, Unplanned return to the operating/procedure room by the same physician or other qualified healthcare professional following initial procedure for a related procedure during the postoperative period, rather than modifier 58 to the subsequent procedure code. When applying modifier 78, the diagnosis typically will be different for each procedure."