In the world of medical diagnostic testing, eye care professionals are fortunate to have some of the most interesting and progressive innovation. Two examples are visual evoked potential (VEP) and electroretinography (ERG).  What were once cumbersome and inconvenient testing routines are now delivered daily in many eye care offices with ease. 

Unfortunately, coverage policies from third party carriers don’t always enjoy the same level of progress as the technological innovations. Thus, be aware of carrier policies regarding VEP and ERG before you administer the tests so you can follow the appropriate rules for non-covered services.

Keep the Patient Informed

If a service is non-covered or you have a specific reason for believing a service will be non-covered, you must inform the patient and give them a choice prior to performing the test with an advanced beneficiary notice (ABN) form. The ABN allows you to identify the test being performed, the reason you believe it will not be covered and the cost the patient can expect to pay should it not be covered or submitted for coverage. This form requires that the patient specify if they want you to proceed with the testing with full knowledge, indicated by their signature, that they may bear full financial responsibility for the cost. 

When you have a completed ABN form, you would typically add modifier -GA or -GX to the CPT code describing the test, indicating that you have a signed ABN on file. This allows the carrier to properly transfer financial liability to the patient should the claim be filed and subsequently denied.

Policies and Expectations

When it comes to electrodiagnostics in eye care, claims are often denied, as the scientific evidence of clinical applicability is still playing catch-up to coverage policies, or vice versa.  

Typical policy coverage for VEP—CPT code 95930. This is appropriate for:

• Confirming diagnosis of multiple sclerosis when clinical criteria are inconclusive.
• Detecting optic neuritis at an early, subclinical stage.
• Evaluating optic nerve diseases, such as: ischemic optic neuropathy; pseudotumor cerebri; toxic or nutritional amblyopia; neoplasms compressing the anterior visual pathways; optic nerve injury or atrophy; and to rule out hysterical blindness.
• Monitoring the visual system during optic nerve (or related) surgery (short-latency evoked potential studies).

Typical policy coverage for ERG. This includes: to diagnose loss of retinal function or distinguish between retinal and optic nerve lesions such as: toxic retinopathies; diabetic retinopathy; ischemic retinopathies such as central retinal and branch vein occlusion and sickle cell retinopathy; autoimmune retinopathies such as cancer- and melanoma-associated retinopathies and acute zonal occult outer retinopathy; retinal detachment; assessment of retinal function after trauma, especially in conditions where the fundus cannot be visualized; absent b-wave indicates abnormality in the bipolar cell region; retinitis pigmentosa and related hereditary degenerations; retinitis punctata albescens; Leber’s congenital amaurosis; choroideremia; gyrate atrophy of the retina and choroid; Goldman-Favre syndrome; congenital stationary night blindness; X-linked juvenile retinoschisis; achromatopsia; cone dystrophy; disorders mimicking retinitis pigmentosa; and Usher syndrome.

Some carriers specifically deny VEP or ERG for glaucoma diagnosis or management as investigational in nature. While you may rightly believe these tests are critical to the early diagnosis of glaucoma or for the management of other diseases, the carrier may not agree with you—and their policies are what you are governed by. Thus, properly providing correct information to your patient and giving them a choice prior to providing the tests is critical to remain compliant under your provider agreement.

Electrodiagnostics are an exciting opportunity, and knowing the rules allows you to provide the very best care while preserving your patients’ right of choice to assume financial responsibility of their care.

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