Ophthalmology and Optometry Coding Alert

Know when to use RT/LT and when to rely on modifier 50.

Don't let tricky prefixes stand in the way of maximum reimbursement for your practice. Read on to learn when you can expect deserved double payment for a service and how to ethically make the most of modifiers.

Dispel Prefix Confusion

The most common mistake new ophthalmology coders make is tripping over the unilateral-bilateral conundrum. Here is the breakdown:

Unilateral means there is a 100 percent allowance per eye. In effect, two unilateral procedures results in a payment equal to 200 percent of the fee, explained Raequell Duran, CPC, president of Practice Solutions, a coding, compliance, and reimbursement consulting firm based in Santa Barbara, Calif., at The Coding Institute's December conference in Orlando.

Bilateral means there is a 100 percent allowance for both eyes. In other words, you can only bill for a bilateral service one time.

Bottom line: Pay special attention when reporting procedures performed on both eyes to avoid missing out on a double reimbursement. Often, but not always, the code description will give you a clue that the procedure can be billed as unilateral.

The following are unilateral diagnostic procedures that generally fall under an ophthalmologist's scope of practice:

 • 92070 -- Fitting of contact lens for treatment of disease, including supply of lens
 • 92135 -- Scanning computerized ophthalmic diagnostic imaging, posterior segment (e.g., scanning laser), with interpretation and report, unilateral
 • 92136-26 -- Ophthalmic biometry by partial coherence interferometry with intraocular lens power calculation; Professional component
 • 92225 -- Ophthalmoscopy, extended, with retinal drawing (e.g., for retinal detachment, melanoma), with interpretation and report; initial
 • 92226 -- ... subsequent.

Know Which Modifier Fits the Bill

Even though a code may be inherently unilateral, you should include the proper modifiers to document that the doctor performed the service on both eyes.

Example: If you are reporting 92135, append modifier 50 (Bilateral procedure) with a unit of 2 to bill for two eyes, says Kennard Singh, CPC, CCS-P, CHCO, of the SUNY College of Optometry in New York, N.Y.

Follow this rule: To use modifier 50, you must use the same diagnosis code for both eyes, said Duran. If the diagnosis code is different, use RT/LT modifiers instead, she added.

Example: If the ICD codes you're reporting for each eye are different, report 92135-RT (Right side) on line 1 of the claim form and 92135- LT (Left side) on line 2, offers Sylvia Conrad, insurance coordinator with Your Eye Solution in Jacksonville, Fla.

When coding a bilateral procedure, remember that in almost every case you would report only one unit and refrain from appending a modifier, explains Singh. For example, the following procedures are almost always bilateral:

 • 92250 -- Fundus photography with interpretation and report
 • 92083 -- Visual field examination, unilateral or bilateral, with interpretation and report; extended examination (e.g., Goldmann visual fields with at least 3 isopters plotted and static determination within the central 30 degree, or quantitative, automated threshold perimetry, Octopus program G-1, 32 or 42, Humphrey visual field analyzer full threshold programs 30-2, 24-2, or30/60-2).

Exception: If you've been coding long enough, you know that special circumstances may arise. For example, if the doctor is performing 92250 on a patient with one blind eye, you would append modifier 52 (Reduced services) to represent the lower level of service associated with this typically bilateral code, Conrad points out.

Last word: When in doubt, reference the "Bilateral Surgery" column (column T) in Medicare's physician fee schedule to see if Medicare assumes that a procedure is bilateral, suggests Conrad.

For 92250, you will find a "2" in column T, meaning you will only receive reimbursement for this procedure once per allowable period. A "0" or a "3" in the T column also indicates absence of bilateral payment. On the other hand, a "1" in column T means you're free to append modifier 50 when appropriate to earn a double payment.