Methods for evaluating the visual health and care for patients with retinal disease have changed dramatically in the last hundred years, but evaluation still requires multiple tools to obtain a complete picture of visual health. Modern electroretinography (ERG) is a valuable method available today that eye care professionals can use in conjunction with existing methods to support confident care decision-making, but some are unaware of the reliable data it provides and the benefits it offers for in-office testing.
In a recent eBook for Ophthalmology Times, Suber S. Huang, MD, MBA discusses the outcome of leveraging the quantitative measurement of retinal function captured with flicker ERG testing to inform the care of an 88-year-old patient with central retinal vein occlusion (CRVO), where OCT results remained stable during anti-VEGF treatment. With the help of electroretinography testing, the retina specialist was able to identify functional improvement and stability, which allowed him to make a more informed care decision.
Learn more about one retina specialist’s experience treating a patient using anti-VEGF medication and leveraging OCT and modern ERG testing to deliver care.
An 88-year-old male patient with a history of coronary artery disease complained of blurred central vision in his right eye. His ocular history included cataract extraction OU, laser posterior capsulotomy OS, chronic open-angle glaucoma OU, and dry age-related macular degeneration OU.
The patient was on timolol maleate 0.5% OU qam and latanoprost 0.005% OU qhs. To treat central retinal vein occlusion OD, the patient was given anti–vascular endothelial growth factor medication, specifically intravitreal bevacizumab injections OD, in an effort to prevent structural damage that may lead to permanent severe vision loss.
The retina specialist utilized optical coherence tomography (OCT) and Diopsys® ffERG/Flicker testing to observe treatment effectiveness and guide the course of care. Although OCT is an objective tool that many professionals use in their clinical practice to evaluate patients with retinal disease, its results provide insight only on posterior pole region structure. Fundus photography, another useful method for evaluating retinal anatomy and physiology, also does not measure global retinal function. These tests leave a gap in knowledge on the potential for functional loss or gains without demonstrable structural changes. To create a more complete study of the patient’s retinal vascular disorder, the retina specialist used full field flicker ERG testing to measure the function of the entire retina.
- Cone-Driven Function: Works with a flash stimulus of high frequency measuring cone-driven function for objective, functional, qualitative results
- Diabetic Retinopathy Treatment Tracking & More: Is suitable for conditions that can cause generalized retinal dysfunction and can be leveraged for patient evaluation, treatment tracking, and follow-up
- Patient-Friendly: Uses comfortable disposable sensors placed on the lower lid and forehead for an in-office test that can be set up and completed in less than ten minutes
- Better Approach to Data: Generates clear, concise, intuitive, color-coded reports that are an improvement upon older ERG reports many professionals found difficult to interpret
Results from observing the patient following their frequent intravitreal bevacizumab injections showed structural stability and improvements in function.
- Initial Testing: OCT showed minor macular involvement possibly due to CRVO, but no significant structural abnormalities. Flicker ERG results showed dysfunction with a Phase response of 258.27°.
- 1 Month Post First Injection: OCT showed no significant structural change and flicker ERG results showed functional improvement, with a Phase response of 279.40°.
- 1 Month Post Second Injection: OCT showed no significant structural change and flicker ERG results revealed additional functional improvement, with a Phase response of 301.11°.
- 1 Month Post Third Injection: OCT showed no significant structural change and flicker ERG results showed functional stability, with a Phase response of 293.99°.
With information from both OCT and ERG testing, the retina specialist made the decision to discontinue anti-VEGF treatment and proceed with routine care and thorough follow-up. Flicker ERG’s quantitative data allows the longitudinal evaluation of retinal diseases that affect global retinal function, supporting disease progression tracking, management, and tailoring care for conditions like diabetic retinopathy, central retinal vein occlusion, chorioretinal Inflammation (uveitis), and inherited retinal dystrophies.2-6
Learn more about the benefits of modern flicker ERG and how clinicians use it in their clinics today, plus see sample Diopsys® ffERG/Flicker reports in the full eBook from Diopsys and Ophthalmology Times.
1. Huang, Suber, MD, MBA, “Shifting the Paradigm for Retinal Disease Management: The Value of Modern Electroretinography.” Ophthalmology Times, 2019. 2. Holm K, et al. Peripheral retinal function assessed with 30-Hz flicker seems to improve after treatment with Lucentis in patients with diabetic macular oedema. Doc Ophthalmol. 2015;131:43-51. 3. Yasuda S, et al. Flicker electroretinograms before and after intravitreal ranibizumab injection in eyes with central retinal vein occlusion. Acta Ophthalmol. 2015;93:e465-8. 4. Larsson J, Andréasson S. Photopic 30 Hz flicker ERG as a predictor for Rubeosis in central retinal vein occlusion. Br J Ophthalmol. 2001;85:683-5. 5. Moschos MM, et al. Electrophysiological examination in uveitis: a review of the literature. Clin Ophthalmol. 2014;8:199-214. 6. Schroeder M, Kjellström U. Full-field ERG as a predictor of the natural course of ABCA4-associated retinal degenerations. Mol Vis. 2018 Jan 4;24:1-16.