P100 Wave Latency in Anisometropic and Esotropic Amblyopia versus Normal Eyes.

Ebrahim Jafarzadehpur,Saeedeh Hosseinmenni,Mohamadreza Talebnejad,Enayatollah Osroosh,Ali Mirzajani

doi:10.4103/2008-322x.170359

Abstract

Purpose:To evaluate cortical activity using pattern visual evoked potentials (PVEPs) in patients with mild and moderate amblyopia (esotropic and anisometropic).Methods:PVEP was recorded in 43 unilateral amblyopic patients, including 15 esotropic (ET) and 28 anisometropic (AM) patients, selected from three different medical centers in the city of Shiraz, Iran and compared to that obtained from 15 age and sex matched normal subjects who served as controls. Visual acuity (VA) in amblyopic eyes was equal to or less than 0.7 LogMAR. The latency of P100 was recorded monocularly using two check sizes of 15 and 60 min of arcs at two different levels of contrasts (30% and 100%).Results:P100 latency in amblyopic eyes was significantly increased compared to the normal group (P < 0.001). There was a significant difference (P < 0.001) in P100 latency in anisometropic and esotropic amblyopic eyes as compared to normal subjects, using high spatial frequency and with both levels of contrast. A significant difference was observed with large check sizes and high contrast between anisometropic amblyopic and normal eyes (P = 0.03). However, there was no significant difference between these two groups and the control group with other stimuli.Conclusion:The neural response based on p100 latency in PVEP was different between amblyopic groups and normal subjects. PVEP may be valuable for diagnosis, prognosis and treatment of amblyopia.

Highlights

P100 latencies in anisometropic amblyopic eyes were longer than normal eyes, using small check sizes and at both levels of contrasts, (P < 0.001) [Table 1, Figures 1 and 2]
Amblyopia is considered as a disorder of cortical function.[8]
Studies have not precisely shown the level at which these deficits occur, valuable studies performed over many years employing different tests, such as, electrophysiology, functional magnetic resonance imaging (MRI) and positron emission tomography (PET) have approximated the location of these deficits.[7,16,17,22,23,24,25]

Summary

Introduction

Amblyopia affects 2.5% of the population and is one of the most important causes of vision loss in children; Received: 17‐08‐2014Accepted: 06‐03‐2015Access this article onlineQuick Response Code: Website: www.jovr.orgDOI: 10.4103/2008-322X.170359 not surprising it has been the subject of many studies.[1] Any vision reduction because of retinal image blur and suppression, such as anisometropia, strabismus or light deprivation, is considered as amblyopia.[2] Studies have shown that amblyopia is not simple vision reduction; it is a complicated mechanism of developmental malfunction in the brain[3,4] Therefore, untimely treatment and diagnosis of the disorder may cause irreversible dysfunction and seriously affect the patient’s qualityThis is an open access article distributed under the terms of the Creative Commons Attribution‐NonCommercial‐ShareAlike 3.0 License, which allows others to remix, tweak, and build upon the work non‐commercially, as long as the author is credited and the new creations are licensed under the identical terms.How to cite this article: Hosseinmenni S, Talebnejad MR, Jafarzadehpur E, Mirzajani A, Osroosh E. P100 wave latency in anisometropic and esotropic amblyopia versus normal eyes. J Ophthalmic Vis Res 2015;10:268-73.

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Results

Conclusion