Diabetic Retinopathy

Patients with diabetic retinopathy have ERGs that become more abnormal with the progression of their retinopathy. The most sensitive features of the ERG to diabetic retinopathy are the flicker ERG and oscillatory potentials (OPs). The OPs amplitude is reduced with diabetic retinopathy. The flicker ERG amplitude is reduced and the implicit time is lengthened with diabetic retinopathy. These ERG parameters are sensitive predictors of progression to high risk characteristics in eyes with diabetic retinopathy, and provide unique predictive information that supplements ophthalmoscopy and fluorescein angiography.

Related Tests

• ERG
• DR Assessment Protocol
• Oscillatory Potentials (OPs)

Related Products

• RETeval® Visual Electrodiagnostic Device
• UTAS Visual Diagnostic System

Central Retinal Vein Occlusion (CRVO)

The ERG is a sensitive and specific predictor of eyes with CRVO that will develop neovascularization of the iris (NVI) and subsequent neovascular glaucoma. A simple few minute test — the 30 Hz flicker ERG — taken the first time the patient presents with symptoms of CRVO, can predict with 93% accuracy whether the patient will develop NVI. Studies have shown that the ERG is much better at predicting outcomes in this disease than is fluorescein angiography.

Related Tests

• ERG
  • 30 Hz Flicker

Related Products

• RETeval Visual Electrodiagnostic Device
• UTAS Visual Diagnostic System

Stenosis of the Carotid Artery

The effect of carotid artery stenosis on the ERG depends upon the extent and severity of the occlusion, and the amount of collateral circulation that has developed through the circle of Willis and the external carotid artery. As the eye becomes more ischemic, developing venous stasis retinopathy, a-wave and b-wave amplitude and timing are significantly affected, and the 30 Hz flicker response is notably delayed.

Related Tests

• ERG
  • 30 Hz Flicker

Related Products

• RETeval Visual Electrodiagnostic Device
• UTAS Visual Diagnostic System

Sickle Cell Retinopathy

In patients with sickle-cell retinopathy in the absence of peripheral retinal neovascularization, ERG the a-wave and b-wave have normal amplitude and timing, and oscillatory potential amplitudes are normal. If peripheral retinal neovascularization is present, all ERG components are reduced in amplitude.

Related Tests

• ERG
  • Oscillatory Potentials (OPs)

Related Products

• RETeval Visual Electrodiagnostic Device
• UTAS Visual Diagnostic System