Modifier 24: Use It Correctly and Avoid Denials

As a practice manager or physician owner, the last thing you want is a payer going over your claims documentation with a fine-toothed comb. And the second-to-last thing you want is for your practice to lose money. To avoid both, you must learn to use modifiers correctly. But modifiers—especially 24—are trouble spots even for experienced coders and billers. On one hand, modifiers communicate valuable payment and informational data. On the other hand, misuse leads to claims denials and could even trigger an audit.
“The potential for lost revenue or even overbilling leading to chart audits is often due to misuse of modifiers,” according to Elizabeth Cottle, COC, OCS, a presenter at AAO 2017. There are a lot of modifiers, but the OIG included only three in its still-influential 2015 report “Questionable Billing for Medicare Ophthalmology Services.” Modifier 24—unrelated evaluation and management by the same physician during a postoperative period—was one of them. (The others were 25 and 22.) “Global period billing is consistently on the OIG watch list” and a hot spot for RAC auditor review, warns Cottle.
Eyes Open: Payers consider physicians in the same group practice (identified by the same tax identification number) and the same specialty to be the “same physician” used in the modifier’s description. “Providers in the same group and same specialty are impacted by each other’s post-op,” Cottle notes.
The Problem
For eye care providers, modifier 24 is most often used during the 90-day global period of cataract surgeries. The OIG report found that providers with an unusually high percentage of claims with modifier 24 were inappropriately appending it to increase their reimbursements. (Remember: modifier 24 causes payers to pay for E/M or eye exam services that would normally be included in the global period). How?
Cataract surgery is almost always done in two phases—first one eye, then the other. The OIG found that some providers were using modifier 24 to bill an E/M or eye code on the second eye for what should have been the post-op visit for the first eye. The OIG did not like that. At all. And it turns out that private payers don’t like it either.
“I’ve been in a whole lot of practices where they do the bilateral cataract, which is basically all the time, and then they try to bill an E/M or Eye code on that post-op visit in between,” says Rhonda Buckholtz, CPC, CPCI, CPMA, CDEO, CRC, CHPSE, COPC, CENTC, CPEDC, CGSC, vice president of practice optimization at Eye Care Leaders. Their rationale? At the pre-op visit, the physician makes the decision to operate on one eye only—they can’t decide to operate on the second eye before evaluating the first eye’s outcome. At the post-op visit, they “decide” to do the second eye, then bill an exam using the same diagnosis for the second eye as the first, and think that’s alright because it’s a different anatomical area.
Why This is Wrong
“You can’t do it because you’ve seen the patient, and you’ve diagnosed bilateral cataracts,” says Buckholtz. “The plan is ‘Let’s do the right eye, and then after we do that we’ll do the left eye.’ You’ve already made the decision for surgery,” she continues. The coding experts at the American Academy of Professional Coders agrees. They state:
When a patient is examined, and the decision [is] to perform cataract surgery in both the right and the left eye, report the appropriate new or established E/M or a 92xxx [Eye] code with the visit date. When the right cataract surgery is performed, report the cataract surgery code with the appropriate date of surgery. When the left cataract surgery is performed, report the CPT® code for the cataract surgery and the appropriate date. Any examination of the left eye performed prior to the left cataract procedure is included in the global service of the right eye surgery.
As long as you are in that 90-day global period, you can’t bill for an exam with that same diagnosis unless the patient is experiencing trouble or something has significantly changed. That might include a bad outcome from the first surgery, new symptoms in the second eye, or some change in the patient’s health that would make you totally re-evaluate the decision for surgery on the second eye. If that’s really the case, be sure to have separate documentation that includes support for a separate visit.
Is there a Loophole?
Practices have sometimes had success and gotten paid when appending modifier 24 inappropriately, but payers have caught on and practices should put themselves one step ahead and append it only when it’s appropriate and documented. Buckholtz has seen cases where the physicians think ‘Ok, well on that first visit, I’m going to document only the right eye and at the post-op I’ll document the left eye’ thinking that’s the way they’re going to get around it. But that won’t work, because it creates a standard of care issue. “When is it ever appropriate to only examine one eye and not document your findings?” asks Buckholtz. “Your malpractice or risk carrier will absolutely tell you not to do that.”
“Payers are starting to go back and audit and recoup that money,” Buckholtz notes. So if you do get paid, it’s probably not money that you’ll be able to keep long-term. When you are audited and you send your records, you’ll have to prove medical necessity, and “there’s no medical necessity for billing like that,” says Buckholtz. “Any exam you bill for during the post-op period has to truly, entirely, be out of the global scenario.”
There’s More at Stake
“This is more than just billing,” Buckholtz warns. When modifier 24 is used this way, all of those post-op visits aren’t getting billed as post-op visits. Remember, modifiers don’t simply adjust payments—they also communicate data. “When we don’t report global periods correctly, we’re skewing data. Those cataract codes will be going back to the RUC committee for re-evaluation,” explains Buckholtz. You’re trading short term gains for long-term losses for the whole industry. “If it looks like providers are not providing post-op care, when those codes are up for re-evaluation, we’re going to see payment reductions,” warns Buckholtz.
What is Routine Post-op Care?
You won’t get reimbursed for providing routine post-op care during a global period, even if you append a modifier to the code. Routine postoperative care includes:
- Treatment for surgical complications that do not require a return trip to the operating room. (for a return trip to the OR, you’d use modifier 78)
- E/M visits related to the patient’s recovery
- Pain management
- Dressing changes
- Incisional care
- Removal of sutures, staples, lines, wires, tubes, drains, catheters, casts and splints
Don’t Forget! Append modifier 24 only to E/M or Eye codes. Modifier 24 may not be appended to procedure codes, labs, x-rays, or supply codes.
It’s All Relative
In order to figure out whether or not to use modifier 24, ask yourself two things:
- Are we within the global period?
- Is the issue related to the surgery?
In order to use modifier 24, the problem or condition for which the exam takes place must be completely unrelated to the cataract surgery. It could be a problem with the other eye, or it could be that something different happened to the eye that was operated on.
Tip: To determine whether the exam is related or unrelated to the surgery, ask yourself “would the patient have this problem if the surgery had not occurred?” If the answer is no, do not use modifier 24.
Are you in the post-op period? Cottle recommends making a spreadsheet for your coders so they can find that information easily and quickly (i.e. without have to count days on a calendar every time.) For each month of the year, list every day’s date in one column, and the end dates of 10- and 90- day post op periods in the other.
Use Modifier 24 Sparingly
If we’ve scared you away from ever using modifier 24 again, fear not. You can use it in the right situations; you just can’t use it routinely. Yes, what happens with the first eye could affect the decision to operate on the second eye. But most carriers assume the ophthalmologist makes the initial decision to operate on both eyes during the preoperative exam. Therefore, they interpret that second visit as post-op care, even if that’s the time when the second eye is scheduled. Scheduling doesn’t matter—the decision to operate matters.
“If something happens after the first surgery that affects the treatment of the second eye, yes, you can use modifier 24,” Buckholtz advises. “But you can’t use it routinely every single time or even all that frequently.” AAO agrees. “There may be concern with the term “frequently” as most exams during the global period are focused on the reason for the procedure,” according to a February 2016 segment of Ask the Coding Experts. “All payers monitor this modifier, including Office of Inspector General,” they write.
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