Multifocal Electroretinogram in normal subjects

Abd Allah, Ahmad Mustafa; Ammar, Hatem; Tamam, Kariman; Shimada, Yoshiaki

doi:10.21608/smj.2017.40534

Multifocal Electroretinogram in normal subjects

Document Type : Original Article

Authors

¹ Department of Ophthalmology, Faculty of Medicine, Sohag University.

² Ophthalmology Department, Fujita Health University School of Medicine, Nagoya, Japan.

10.21608/smj.2017.40534

Abstract

Background: Multifocal electroretinogram (mfERG) is a device for recording the physiological response of multiple retinal areas in short time. Using this technique enables us to detect the spatial extent and severity of the retinal damage. Objectives: In this study,we aimed to assess the topographic properties of mfERG in normal subjects to use it as a basic data to evaluate eye disease. Methods: We recorded mfERG from 20 eyes of 20 normal subjects. We measured amplitude and latency of recorded waves. We compared between amplitude of these waves between different retinal areas and the same for latency. Results: We found mfERG responses in the form of waves, every wave consists of negative wave (N1) followed by positive wave (P1). The amplitude of N1 wave and amplitude of P1 were largest at the fovea and decreased toward periphery. The latency of N1 and P1 were shorter in upper retina than lower retina. The N1 amplitude and P1 amplitude was larger in upper retina than lower retina, which reflex functional superiority of upper retina. There was no statistical difference between nasal and temporal retina in the amplitude and latency.Conclusion: Multi-focal ERG would be useful for objective examination of the retinal function.

Keywords

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