Optometry Coding & Billing Alert

Getting reimbursed for 92135 can be tricky, but our expert coding tips will leave your claims beaming

Though it's still a new technology, optometrists are already touting the benefits of scanning laser glaucoma testing (SLGT) in early detection of eye disease. Recognizing the value of coding correctly for SLGT will lead to early detection of problems leading to carrier denials. We've got the scoop on how to avoid these common pitfalls of SLGT coding and billing.

Dig In to the Alphabet Soup

To correctly code and bill for SLGTs, you need to understand that optometrists get diagnostic images through SLGTs through a variety of technologies:

Confocal laser scanning topography uses simultaneous stereoscopic (confocal) digital video images to produce a three-dimensional image of the eye's posterior chamber and give a quantitative measurement of the optic nerve head and surrounding retina.

Also known as: HRT1 or HRT2 (Heidelberg Retina Tomograph), optic nerve head imaging.

Scanning laser polarimetry uses a polarimeter to measure linear polarization change and a scanning laser ophthalmoscope to measure the thickness of the nerve fiber layer of the retina.
 
Also known as: SLP, GDX, GDx-VCC, nerve fiber analyzer.

Optical coherence tomography produces high-resolution longitudinal cross-sectional tomographs of the eye's structures. It's similar to a B-scan, only using light instead of sound to produce the image.

Also known as: OCT, RTA (retinal thickness analyzer).

Note: SLGTs in general are sometimes referred to as scanning computerized ophthalmic diagnostic imaging (SCODI).

Key: CPT has one code to describe all of the SLGT tests - 92135 (Scanning computerized ophthalmic diagnostic imaging [e.g., scanning laser] with interpretation and report, unilateral) - says Terri Davis, CPC, biller for Tullahoma Eye Care in Tullahoma, Tenn.

Report These 92135 Components

CMS has divided the relative value units (RVU) for 92135 into a technical component and a professional component, Davis says. In Medicare's 2005 fee schedule, the total unadjusted RVUs for 92135 are 1.16. Multiplying that by the conversion factor of 37.8975 means that an optometrist performing both the technical and professional components would earn about $44.
 
The technical component alone is worth 0.65 RVUs. If your office only performs the test (technical component) and does not read the results, you must bill code 92135-TC (Technical component) and earn about $25. If another office performs the technical component, however, and you physician does the interpretation and report, append modifier -26 (Professional component) to code 92135,  Davis says. You would earn 0.51 RVUs - about $19 - for that service.

Modify Claims for Bilateral SLGT

Medicare considers 92135 to be inherently unilateral, Davis says, meaning that the RVUs in the fee schedule represent the work done on only one eye. If you do perform an SLGT on only one eye, report one unit of 92135 and append the alphabetic modifier -RT or -LT to indicate which eye you tested.

Carriers differ on how you should report a scanning laser test on both eyes. Medicare and many private carriers look for 92135 reported on two lines of the billing form, each with a "1" in the units field and with the -LT and -RT modifiers appended, says Adrienne Smith-Poch, billing manager for Eyes of York in York, Pa. However, some carriers may want you to report one unit of 92135 with modifier -50 (Bilateral procedure) appended.

Double-Check Medical Necessity

You must document the reason for the laser scan in the patient's record, and the reason must demonstrate medical necessity. For example, if a patient presents with increased intraocular pressure, OCT can help determine whether the patient is in the early stages of glaucoma, a circumstance that constitutes medical necessity. There should be documented medical necessity for each eye, since each is a separate test.

Include a Written Interpretation

To bill code 92135, you must include in the medical record a written interpretation and report that includes any findings and observations from the imaging report. The report should explain what findings the physician is able to abstract from the test. The interpretation of the test results should also include any issues of the quality of the test, reliability of the findings, and any implications for treatment or further care.

Watch Those Bundles

Most individual carriers have limits on how often - and at what point in the glaucoma's progress - you can perform this test. The scanning laser is best used in glaucoma in its early stages, when early problems can be discovered and treated without unnecessary medical or surgical intervention.

Therefore, many carriers will pay for visual field testing (92081-92083), but not for the scanning laser in advanced stages of glaucoma, Smith-Poch says.

Carrier example: Empire Medicare, the Part B carrier for New Jersey and parts of New York, has a typical local coverage determination (LCD) for 92135. They allow optometrists to use SLGT to follow "preglaucoma patients or those with mild damage."

Other carriers, such as CIGNA in North Carolina, further refine this to limit SLGT to once a year for patients with mild damage.

In a patient with moderate damage, you may perform SLGT or visual fields - but not both, at least not "done together or separated by a short period of time [such as] three months. However, alternating use of these tests at the proper time intervals can be considered appropriate." For patients with advanced damage, "visual fields would be preferred."

NCCI bundles 92250 (Fundus photography with interpretation and report) with 92135 as mutually exclusive procedures, meaning they would not expect both to be medically necessary at once. And some carriers, such as HealthNow in upstate New York, also consider other procedures "generally not necessary" with 92135: