The study of local electrophysiology in macular diseases

Abstract

Purposes: To observe the features and clinical utility values of local electroretinogram (LERG) and local visual evoked potentials (LVEP) in macular diseases.

Methods: The spot stimuli were obtained by changing the shutters with different sizes of hole at the posterior of Ganzfeld ball. The recording electrode for LERG was made with the filament of platinum as blepharophthalmostat like. The LERG and LVEP were simultaneously recorded in macular diseases.

Results: The exudative AMD, Stargardt's disease, central serous chorioretinopathy and idiopathic macular hole had seriously decreased amplitudes of LERG and higher abnormal rates, comparing with atrophic AMD and idiopathic preretinal membranes in the region of 2.5 degrees and 5 degrees at macula. The abnormal rates in these diseases were higher for LERG than for LVEP.

Conclusion: The LERG can objectively measure the variation of macular function in maculopathies. The sensitivities of LVEP are lower than those of LERG for macular diseases.