Electrophysiological approaches for early detection of glaucoma
Related Experiment Video
Updated: Oct 4, 2026

Assessing Early Stage Open-Angle Glaucoma in Patients by Isolated-Check Visual Evoked Potential
Published on: May 25, 2020
1Ophthalmic Department, University of Freiburg, Germany. bach@uni-freiburg.de
Purpose:
While elevated intraocular pressure (IOP) is a major risk factor for glaucoma, only about 1% of patients with 25 mmHg develop the condition each year. Since a sizeable proportion of the ganglion cells are already lost when the visual field losses are apparent, the aim is to identify patients with elevated IOP in whom glaucoma damage is incipient before visual field changes occur.
Methods:
This report concerns early diagnosis of glaucoma with electrophysiological techniques, rather than with monitoring the disease using various available psychophysical and morphological methods. Visual electrophysiology offers a wide range of tools to assess function layer-by-layer along the visual pathway. Their clinical value for early detection of glaucoma will be discussed. The pattern electroretinogram (PERG), a direct functional indicator of retinal ganglion cell function, is markedly affected by glaucoma, and in longitudinal studies the PERG correctly indicated eyes at risk before manifest glaucoma occurred.
Conclusions:
Consequently, this report will concentrate on the PERG. Less proven, but promising measures like the "photopic negative response", the motion visually evoked potential (VEP) and the multifocal VEP will also be touched upon.
