Purchase this article with an account.
R. Blanco, J.L. Liang, P. Martinez, J.A. Alvarado, E.E. Sutter; Multifocal Electroretinography Evaluation in Normal–Tension Glaucoma Patients . Invest. Ophthalmol. Vis. Sci. 2006;47(13):1661.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To evaluate the electrophysiologic function in normal–tension glaucoma by using: 1) a new protocol of the multifocal electroretinogram (mf–ERG) that emphasizes response contributions from ganglion cell fibers (optic nerve head component (ONHC)) and 2) the standard m–sequence paradigm of the mf–ERG that emphasizes response contributions from the outer retina function.
mf–ERGs in both eyes of 14 individuals with the presumed diagnosis of normal–tension glaucoma were recorded and analysed with the VERIS 5.1 multifocal recording system. The special, ganglion cell response enhancing protocol consisted of multifocal flash stimuli interleaved with two global flashes presented 13.3 ms and 40 ms after each multifocal frame. The intensity of both multifocal and global flashes was 2.7 cd•s/m^2. The stimulus array consisted of 103 scaled hexagons. The recording time was 9 minutes per each eye. Pupils were dilated. The effect induced by the focal flashes on the second one of the following global flashes contains the most prominent ONHC and was thus used for the evaluation of the mf–ERG data. The m–sequence paradigm of the mf–ERG was also applied in all cases and the first–order kernel evaluated (103 hexagons; 2.7 cd•s/m^2 peak luminance and 7 minutes per each eye).
Five patients (35.7%) were shown to have significant bilateral outer retina dysfunction (AZOOR, occult macular dystrophy, myopic retinopathy, atypical retinosis pigmentosa and white dot syndromes). Three patients (21.4%) were shown to have non–glucomatous optic neuropathies (optic nerve drusen, optic nerve hypoplasia and anterior optic neuropathy).
1) The mf–ERG technique can detect and map functional deficits due to either outer or inner defects that are not clearly discriminated using current automated perimetry tests. 2) the mf–ERG can be specially useful in the routine work–up in normal–tension glaucoma suspects ruling out photoreceptor and/or inner retina dysfunction, nonorganic visual loss and patients with unreliable automated visual fields.
This PDF is available to Subscribers Only