Visual Electrophysiology, ERG, VEP & Psychophysics

The New England Eye Center offers a full complement of eletrophysiologic tests including multifocal electroretinography (mfERG) and multifocal visual-evoked potentials (mfVEP). Patients also can be referred for standard ERG and VEP as well as advanced color vision testing or contrast sensitivity testing. Testing usually takes less than two hours, and a report can be faxed to the referring doctor within 24 hours. Retinal, neuro-ophthalmic, or pediatric consultation can be arranged to coincide with testing. Such a consultation will be performed only when requested by the referring doctor.

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Electroretinography (ERG)

Full-field ERG testing is available for patients with hereditary retinal degeneration, suspicion of ocular siderosis, cancer/melanoma associated retinopathy, retinal vascular disease, and assessment of retinal function due to media opacity. Macular function can also be assessed using multifocal ERG recording in patients with occult macular degeneration, unexplained visual loss and for distinguishing between retinal and optic nerve disorders. Multifocal ERG is especially useful for patients suspected of having Plaquenil maculopathy. Electrooculography is available for evaluating patients suspected of having Best's disease.

Visual Evoked Potential (VEP)

Assessment of disorders of the optic nerve and visual pathways can be performed objectively by measuring the visual-evoked potential (VEP). Standard VEP has been used for years in the diagnosis and management of demyelinating optic neuritis. Standard VEP as well as multifocal VEP are especially useful in proving non-organic loss of visual acuity and visual fields. We are engaged in development of mfVEP testing which we expect will allow for objective visual field testing for a variety of other conditions.

Psychophysics Service

Preferential looking in conjunction with visual evoked potential (VEP) can be performed to assess visual acuity in infants and nonverbal children during a single appointment in our facility. Advanced color vision testing (Farnsworth D-15 and D-100) and contrast sensitivity testing also are available.