98th Annual Meeting DOG 2000

V 159

Multifocal ERG in age-related macular degeneration with geographic atrophy

M. Weismann, B. Jurklies

Introduction: To investigate the effects of age-related macular degeneration (AMD) with geographic atrophy on retinal function using multifocal electroretinography (MERG).

Methods: Based on color fundus photography and fluorescein angiography 81 eyes of patients with non-exsudative AMD were classified in 2 groups. Group I had geographic atrophy (27 eyes) and drusen while group II had drusen only (54 eyes).

Using MERG (VERIS, EDI, San Francisco) 103 focal ERG of the central 25°x30° evoked by hexagonal stimuli were recorded. The 1st order kernel was extracted. Mean amplitudes and implicit times of the first through ("a-wave") and peak ("b-wave") were calculated on the basis of concentric rings (ring 1 centre to ring 6 periphery) centred around the fixation point.

Results: Mean amplitudes ("a-, b-wave") of group I and II were statistically significant reduced compared to a normal control group and compared to each other. They were reduced more in the centre than in the periphery and more pronounced for group I than for group II.

Mean implicit times ("a-, b-wave") of group I and II were statistically significant prolonged compared to a normal control group. They were prolonged more in the centre than in the periphery and more pronounced for group I than for group II.

Discussion: Geographic atrophy induced significant changes in amplitude and implicit time of "a-, and b"-wave. Local responses were affected more by geographic atrophy than by drusen only.

Supported by Deutsche Forschungsgemeinschaft (DFG, grant JU 379/1-1)
Electrophysiology Lab, Dept Ophthalmology, University Hospital, D-45122 Essen, Germany



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