Audit-Proof Your Diagnostic Testing Coding & Billing

Performing diagnostic testing services can be fairly routine—but collecting for them is not. Between modifier requirements, medical necessity denials, and documentation rules, practices face myriad challenges in meeting payers’ guidelines so they can bring in diagnostic testing cash. Knowing how to pinpoint when those tests are billable (and when they’re not) is often tricky. But today, I’m pulling back the curtain on how to collect for these services.

Following a few simple strategies can help you avoid denials and keep auditors from nosing around your claims.  Although many practices think an audit can’t happen to them, the reality is that reviews are happening every day. They don’t always require an auditor to be standing at your door — many occur offsite just from reviewers looking at your claims and medical records.

Here’s the scoop on diagnostic testing:

A recent OIG report found that Medicare paid $171 million to ophthalmologists for services that turned out to be billed questionably, and the agency has since aimed its audit focus on eye care providers who may be following suit. Both government and private payers are stepping up reviews of ophthalmology and optometry practices to ensure that all services are reported appropriately.

In addition, recovery audit contractors (RACs) are stepping up their reviews of eye care practices, with audits of cataract claims, pre-operative visits and other services on their radar screens for this year. With these types of scrutiny bearing down on your practice, it’s a good time to go over a few diagnostic testing best practices.

Get Specific with Visual Field Testing

Ophthalmologists frequently perform visual field examinations (CPT® 92081-92083) to measure a patient’s entire scope of vision and map the visual fields of each eye to detect dim vision and blind spots. Often, these tests are used to evaluate glaucoma damage to the optic nerve, or to detect central or peripheral retinal diseases, eyelid conditions, optic nerve damage and visual pathway conditions.

Despite the wide variety of conditions that physicians evaluate with visual field exams, not every medical record will support these types of tests. The documentation must support the medical necessity for ordering and performing the service. Also, never include gross visual field testing (also referred to as “confrontation testing”) using the CPT® 92081-92083 series. This service is part of the general ophthalmological service and should not be reported separately or you could face upcoding accusations.

You must also ensure that your diagnosis codes don’t indicate that the patient has a condition that she doesn’t actually have. Although this may seem obvious, it can happen when practices see a “rule out” diagnosis and put that on the claim instead of the final diagnosis. If you perform a test to rule out a diagnosis or you end up with an uncertain diagnosis, then report the ICD-10 code based on the signs and symptoms that prompted the physician to order the test, rather than the code for the condition the doctor is ruling out.

Optical Coherence Tomography

Most eye care providers perform optical coherence tomography (OCT) frequently. This non-invasive test uses light waves to take images of patients’ retinas using cross-sectional photography, allowing the physician to view each layer of the retina separately and measure the thickness. These measurements allow the physician to more accurately treat glaucoma and retina conditions, and can evaluate the optic nerve as well.

Keep in mind that you can only report OCT (92133-92134) once no matter whether you perform the testing on one eye or both. To bill these services with modifier 50 (Bilateral procedure) would constitute inappropriate billing since the code clearly states, “unilateral or bilateral” and therefore the payment is the same for one or both eyes. On the plus side, you need not append modifier 52 (Reduced services) in situations when you address only one eye. Your payment will not be reduced in this situation.

One service you probably can’t report with an OCT is fundus photography (92250), because the Correct Coding Initiative (CCI) considers the codes mutually exclusive. The bundle does have a “1” indicator, meaning you can separate them with a modifier such as 59 (Distinct procedural services) or the LT and RT modifiers (Left side, right side) when you treat separate eyes. However, you shouldn’t try and use modifier 59 to separate the codes when you’re treating the same eye, because that would be considered inappropriate unbundling.

In addition, many insurers maintain frequency guidelines for 92133 and 92134. If the patient has a condition due to retinal disease, you can typically report OCT just once every two months, but it can be payable monthly for macular degeneration or diabetic retinopathy. The key is to check your insurer’s local coverage decision to make sure you’re meeting — and not exceeding — the payer’s frequency guidelines.

Fundus Photography

Eye care specialists use fundus photography (92250) to document the diagnosis and treatment

of eye diseases, and to follow the disease’s course when the patient has a retinal disorder. Insurers have very strict guidelines on how often you can perform fundus photography, and which conditions and diagnoses are billable with this service.

The OIG has found that eye care providers report a high number of fundus photography exams per beneficiary each year, leading the agency to believe they may be reporting services that aren’t medically necessary. This, of course, means more audits for these services, resulting in an essential need to report the codes correctly.

Most payers will only reimburse you for 92250 once or twice a year. The majority of Medicare contractors will reimburse fundus photography every six months for rapidly-evolving diabetic retinopathy, whereas for slower disease processes like glaucoma, contractors typically only reimburse it annually.

IOL Power Calculations

When patients are facing cataract surgery, eye care providers must calculate their intraocular lens (IOL) power, which leads most practices to become accustomed to reporting 76519

(Ophthalmic biometry by ultrasound echography, A-scan; with intraocular lens power calculation) or 92136 Ophthalmic biometry by partial coherence interferometry with intraocular lens power calculation).

Some payers have reported that they’re pinpointing IOL calculations as an audit focus, particularly when practices use the 26 (Professional component) and TC (Technical component) modifiers with these codes. Therefore, it’s important to understand how these modifiers work for IOL services, which is a departure from how you normally use these modifiers.

The confusion arises due to the fact that these codes have different bilateral statuses for the technical component than they do for the professional component. According to the 2019 Medicare Physician Fee Schedule, both 76519-TC and 92136-TC are denoted with modifier indicator “2,” which means that the technical component of the codes is considered inherently bilateral. Therefore, whether you test one eye or both, you’ll report 76519-TC or 92136-TC only once.

However, if you’re billing the professional components (76519-26 and 92136-26) the modifier indicator is “3,” meaning that professional components are inherently unilateral. Therefore, you can add modifier 50 (Bilateral procedure) after modifier 26 if you perform the professional component of this service on both eyes.

The reason for this is that providers will normally perform the technical component of the service (the eye measurement) on both eyes at the same time, but they often perform the actual IOL power calculation (which represents the professional component) on the eye requiring surgery.

Maintain Airtight Documentation

Knowing that auditors are reviewing medical records for eye imaging services, it is essential for practices to maintain thorough documentation that demonstrates medical necessity for these services. Even if you performed the imaging for appropriate reasons, insurers will deny the claims and ask for money back if you can’t prove medical necessity, and the only way to do that is thorough notes.

In the record, make sure you have hard copies of photos, scans or test results that the physician ordered, interpreted or performed. In addition, you should be able to show an order for the test that has the medical rationale for performing it, the test date and findings, confirmed diagnoses (if possible), the treatment plan, the prognosis and a physician’s signature.

Strong documentation will not only help you in an audit, it will also bolster any appeals if your claims get denied. Common denial reasons include:

  • Exceeding insurer frequency guidelines
  • Testing for non-covered indications
  • Lack of medical necessity
  • Inappropriate bundling
  • Misusing modifiers
  • Incorrect diagnosis codes

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