Diagnostic testing for glaucoma suspects never seems to stagnate. Significant changes that apply to recent technologies became effective on January 1, and they may affect how you approach your glaucoma workup.

Declaratory Statements 

First, I am not a glaucoma specialist and rely on both the American Optometric Association (AOA) Clinical Practice Guidelines and the American Academy of Ophthalmology (AAO) Preferred Practice Patterns when discussing recommended tests.1,2 

Second, third-party carriers only pay for testing that is medically necessary for a patient based on their clinical presentation. Therefore, panel testing (i.e., running the same battery of tests on every patient indiscriminately based on a specific diagnosis) is not appropriate. 

Practice Pearls

  • Panel testing is not a sound approach, unless you are billing the third-party carrier only for the tests for which you have clearly established medical necessity.
  • Insurance carriers do not pay for preventive medical testing you do to eliminate or reduce your medical liability.
  • A pattern is emerging where frequently done tests are being re-categorized in the CPT as Category III, which defines them as new or emerging technology. This often shifts the financial responsibility of the test to the patient.

Potential Confusion

As technology continues to expand and drives changes in the patient journey and the quality of clinical outcomes, optometrists must stay abreast of the rule sets and changes that come at a furious pace. Pay attention to the rules of each of your contracted medical carriers, as they can differ based on whether the carrier is commercial, Medicaid, Medicare Part C (Medicare Advantage), or traditional Medicare Part B. And as always, make sure you are aware of these rules prior to providing the care—never assume that meeting the requirements of telehealth for one carrier means you meet the rules for other carriers. 

The latest changes that may affect your clinical decision making have to do with adjunctive testing for glaucoma suspects. Both the AOA and AAO agree that in addition to the physical examination itself, supplementary testing can include:1,2

  1. Visual fields (9208X)
  2. Fundus photography (92250)
  3. OCT of the optic nerve (92133)
  4. Gonioscopy (92020)

This differs significantly from what is typically discussed in continuing education forums today. Other tests, such as visual evoked potential (VEP), electroretinogram (ERG) and corneal hysteresis, conducted and billed for on a standard basis may or may not be appropriate. The recent upswing in the use of these tests for diagnosing “glaucoma suspects” has led to major changes in their coding.

The first change came in 2018 for VEP. Because many were using the 95930 code to test for glaucoma suspects, the AMA removed glaucoma from the CPT definition:

  • 95930: VEP checkerboard or flash testing, central nervous system except glaucoma, with interpretation and report.3

The Category III code, 0464T, was added specifically for use with a glaucoma suspect:

  • 0464T: VEP, testing for glaucoma, with interpretation and report.3

Changing from a Category I to a Category III code also shifts the payment responsibility to the patient.

In 2019, ERG is receiving a similar treatment with the removal of 92275 and the addition of:3

  • 92273: ERG with interpretation and report; full field (i.e., ffERG, flash ERG, Ganzfeld ERG).
  • 92274: ERG with interpretation and report; multifocal.
  • 0509T: ERG with interpretation and report, pattern (pERG).

As with VEP coding, the pERG code, which was typically used for a glaucoma suspect, has been moved to a Category III status, essentially putting it into a patient pay status.

Corneal hysteresis, another test gaining in popularity, has the accompanying code:

  • 92145: Corneal hysteresis determination, by air impulse stimulation, unilateral or bilateral, with interpretation and report.3

While not a new code, it has no current formal policy of coverage set by any Medicare carrier. 


Our mission is to provide comprehensive eyecare responsibly, ethically and at a level commensurate with each patient’s clinical presentation. The changes occurring within the CPT are numerous but ones we are bound to follow. Adhering to the rules helps you provide the individualized care patients deserve and protects you and your practice.

Send questions and comments to rocodingconnection@gmail.com.

1. American Optometric Association. Optometric clinical practice guideline: Care of the patient with open angle glaucoma. www.aoa.org/documents/optometrists/CPG-9.pdf. Accessed January 29, 2019. 

2. American Academy of Ophthalmology. Preferred practice pattern: primary open-angle glaucoma suspect. www.aaojournal.org/article/S0161-6420(15)01278-6/pdf. Accessed January 29, 2019.

3. www.CodeSAFEPLUS.com. Accessed January 29, 2019.