Optometry Coding & Billing Alert

You're 5 questions away from finding out if you've mastered SLGT billing

It's still a relatively new technology, but optometrists have been touting the benefits of scanning laser glaucoma testing (SLGT) in early detection of eye disease. For early detection of problems leading to carrier denials, you need to know the nuances of SLGT coding and billing.

Test your ability to avoid some common pitfalls of SLGT coding and billing:

Question 1: Code 92135 (Scanning computerized ophthalmic diagnostic imaging [e.g., scanning laser] with interpretation and report, unilateral) is the correct code for:

A. Heidelberg Retinal Tomograph test (HRT1, HRT2)
B. Glaucoma Diagnosis test (GDx, GDx-VCC)
C. Optical Coherence Tomography (OCT)
D. Retinal Thickness Analyzer (RTA)
E. All of the above

Question 2: True or false: For coding and billing purposes, 92135 is inherently bilateral.

Question 3: Which of these codes does the National Correct Coding Initiative bundle with SLGT?

A. General ophthalmological services (92002-92014)
B. Visual fields (92081-92083)
C. Extended ophthalmoscopy (92225-92226)
D. Fundus photography (92250)
E. All of the above

Question 4: Which of these ICD-9 codes would not prove medical necessity for SLGT?

A. 362.56
B. 365.00
C. 366.16
D. 377.14
E. None of the above

Question 5: You perform an SLGT and send the results to another physician for interpretation. You should report:

A. 92135
B. 92135-TC
C. 92135-26
D. 92135-52
E. 92499

Answers to SLGT Coding Quiz

Question 1: E. Code 92135 describes all of the tests listed, as well as the nerve fiber analyzer, scanning laser polarimetry (SLP), laser coherence tomography, and optic nerve head imaging tests. SLGTs are sometimes referred to as scanning computerized ophthalmic diagnostic imaging (SCODI).

Question 2: False. When you perform SLGT bilaterally, you must report 92135 either with modifier 50 (Bilateral procedure), with the alpha-modifiers LT and RT, or with a -2- in the units column. Code 92135 is considered inherently unilateral--the fee allotted for 92135 only accounts for what is involved in performing the scanning done in one eye.

Question 3: D. NCCI places 92135 and 92250 (Fundus photography with interpretation and report) into a -mutually exclusive- bundle, meaning that Medicare does not consider both of these tests necessary on the same day. However, you can report the two codes together if you can show that it was medically necessary to perform both tests that day--for instance, due to travel restrictions preventing the patient from returning later for the second test.

Caution: Don't report 92135 and 92250 regularly or routinely, says David Gibson, OD, FAAO, a practicing optometrist in Lubbock, Texas: -Anytime you use modifier 59 (Distinct procedural service), you are waving a flag to attract Medicare's attention. Use 59 when you need it--just be careful to document that it is not abuse.-

Question 4: C. Individual carriers may have different rules, but most would not think that an SLGT would be necessary for a patient with a 366.16 (Nuclear sclerosis) diagnosis. Many carriers have a list of ICD-9 codes that they allow to prove medical necessity for 92135. For example, Part B carrier Trailblazer lists 362.56 (Macular puckering), 365.00 (Preglaucoma, unspecified) and 377.14 (Glaucomatous atrophy [cupping] of optic disc) as approved diagnoses.

Question 5: B. CMS has divided the relative value units for 92135 into a technical component and a professional component. If your office only performs the test (technical component) and does not read the results, you would bill 92135-TC (Technical component). The physician interpreting the results would bill 92135-26 (Professional component).

Appending modifier 52 (Reduced services) would not be appropriate, since modifier TC more accurately describes the work you did. Similarly, you should avoid 92499 (Unlisted ophthalmological service or procedure) unless there is no other CPT code that describes the procedure.

Don't miss: If you perform the test bilaterally, use the appropriate modifiers (see Question 2 above).