Visual fatigue during prolonged visual field testing in optic neuropathies

Publisher Website
Google Scholar
Abstract
Visual fatigue is defined as a loss of visual sensitivity in optic neuropathies during exposure to prolonged or otherwise modified visual stimuli. Repeated light stimulation at a constant place leads to a decay of perception. Program Gl of the automated static perimeter Octopus was used in a group of mild chronic optic neuropathies in order to detect a loss of differential light sensitivity (DLS) from examination phase 1 to phase 2. In the majority of the cases (up to 77%), a loss of DLS was observed from phase 1 to phase 2, while, in a normal control group, a loss in phase 2 was present in 32% only, when all 59 test locations of program Gl were considered. This difference between the neuropathy group and the normal control group is statistically significant. The effect of visual fatigue arises rather from more peripheral parts of the visual field. No differences between neuropathies and normals were found in the performance of the Arden contrast sensitivity test, which was presented twice and which lasts much shorter in time than perimetry.