%0 Journal Article
%T Flash Electroretinography and Pattern Visual Evoked Potential Changes in Ocular Hypertension Patients
%A Erc¨¹ment £¿avdar
%A Abdullah Ozkaya
%A Burcu Alper
%J Journal of Ophthalmology
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/908017
%X Purpose. To evaluate the changes of flash electroretinography (fERG) and pattern visual evoked potentials (pVEP) in ocular hypertension (OHT) patients. Methods. Twenty-five OHT patients and 30 healthy volunteers were enrolled for this cross-sectional study. Opthalmologic examinations, visual field tests, pVEP and fERG were performed. The main outcome measures were the differences between pVEP and fERG parameters. Results. The mean age of OHT patients and volunteers were 57 ¡À 12.25 years (range 30¨C65 years), and 53.25 ¡À 12.0 years (range 30¨C65 years), respectively. The mean amplitude of the pVEP was statistically lower in the OHT group (P < 0.05). Latency of the two groups was different; however, the difference was not statistically significant (P > 0.05). In fERG of OHT group, there was a significant decrease in the amplitude of the oscillatory potentials (Ops), and a significant delay in latency of rod and cone waves (all P < 0.05). There was no significant change in the flicker fERG waves between the two groups (P > 0.05). Conclusions. Although we found a decrease in Ops amplitude and a prolonged latency in flicker fERG, only the decrease in Ops amplitude was statistically significant between the two groups. The amplitude of Ops wave and amplitude of pVEP may reflect early glaucomatous damage in OHT patients. 1. Introduction Glaucoma is an optic neuropathy which generally develops with elevated intraocular pressure (IOP) and leads to the enlargement of the cup disc ratio (C/D) in the optic nerve head (ONH) and visual field loss (VFL) [1, 2]. IOP measurement, assessment of ONH and visual field (VF), and examination of the anterior chamber angle are required in order to diagnose and classify glaucoma. Diagnostic criteria of glaucoma are highly variable. Glaucomatous VFL is one of the most important symptoms of glaucoma and frequently shows correlation with anatomic damage within the ONH. However, VF is affected when the axonal damage reaches 15%¨C50%, and this is the biggest disadvantage of VF testing [3]. Clinical electrophysiological tests allow us to assess the visual pathway as a whole system. Electrophysiological tests provide significant data while revealing and monitoring the pathologies in the visual pathway objectively from the retina pigment epithelium (RPE) to the occipital cortex [4]. A flash electroretinography (fERG) record is generated by the rapid changes of the retinal standing potential following retinal stimulation with a uniform light flash. It is thought that the formation of the waves during the record results from the outer retinal
%U http://www.hindawi.com/journals/joph/2013/908017/