Abstract
Purpose: :
To examine retinal recovery processes topographically by the application of three-flash-sequences with specific interstimulus intervals
Methods: :
11 healthy subjects underwent multifocal ERG testing with an LED stimulator (Roland Consult, Wiesbaden, Germany). Every stimulation step consisted of a three flash sequence with 20 ms between the first and the second and 30 ms between the second and the third flash. The interval between the third and the first flash of the next step was 80 ms. Based on the interstimulus interval dependent amplitude reductions of the multifocal ERG response for these three intervals (higher amplitude reductions with short intervals), the complete curve of the recovery kinetics was determined. Half-life periods of these recovery kinetics were calculated for 5 different rings of retinal excentricity.
Results: :
The mean half-life period of the amplitude recovery across all subjects in the central area was 24.32 ms, 23.16 ms in ring 2, 22.73 ms in ring 3, 17.13 ms in ring 4 and 14.78 ms in the most peripheral ring 5 with significant differences between rings 1 and 2, 3 and 4, 1 and 3, and 3 and 5 (p<0,05).
Conclusions: :
The kinetics of the amplitude recovery after short interstimulus intervals showed a strict spatial distribution with faster recovery towards the macular periphery. Further studies will show, if different pathologies have specific influences on retinal recovery processes and if their analysis can contribute to the diagnostic capacity of the mfERG.
Keywords: electroretinography: clinical • electroretinography: non-clinical