Retinal Nerve Fibre Layer and Macular Thicknesses in Adults with Hyperopic Anisometropic Amblyopia.

Konuralp Yakar,Tolga Ceylan,Mehmet Hanifi Alp,Aydın Alan,Emrah Kan

doi:10.1155/2015/946467

Abstract

Objectives. This study compared the macular and retinal nerve fibre layer (RNFL) thicknesses and optic nerves of eyes with reduced vision due to anisometropia with the contralateral healthy eyes in adults using optical coherence tomography (OCT). Methods. This cross-sectional study was conducted in Atatürk State Hospital, Sinop, Turkey. Macular and RNFL thicknesses, optic nerve disc area, cup area, and horizontal and vertical cup-to-disc ratios obtained using a NIDEK RS-3000 SLO spectral domain OCT device were compared between the amblyopic and fellow eyes in 30 adults with anisometropic amblyopia 18–55 years old who were seen in our clinic with unilateral poor vision. Results. The mean macular thickness was 266.90 ± 23.22 µm in the amblyopic eyes and 263.90 ± 22.84 µm in the fellow eyes, and the mean RNFL thickness was 111.90 ± 12.9 and 109.70 ± 9.42 µm, respectively. The two thicknesses did not differ significantly between the amblyopic and fellow eyes. There were also no significant differences between the eyes in disc area, cup area, and horizontal-vertical cup/disc ratios. Conclusion. There does not seem to be a difference in macular thickness, peripapillary RNFL, or optic disc structures between the amblyopic and fellow eyes in adults.

Highlights

Amblyopia is a neuroanatomical and neurophysiological ophthalmological disorder with no associated pathology of the optical axis or macula that could cause low vision; it cannot be eliminated with refractive correction and may be treated if diagnosed at an early stage
In anisometropic amblyopia, focused and unfocused images coming out of the point of fixation produce a blurred image in the fovea of the eye and an abnormal binocular interaction develops to the disadvantage of the eye with blurred vision as a result of overlapping clear and blurred images, leading to inhibition of the fovea and poor vision in that eye [2]
Studies have demonstrated that the lateral geniculate nucleus and visual cortex are the structures that are primarily affected in amblyopia [8,9,10]

Summary

Introduction

Amblyopia is a neuroanatomical and neurophysiological ophthalmological disorder with no associated pathology of the optical axis or macula that could cause low vision; it cannot be eliminated with refractive correction and may be treated if diagnosed at an early stage. Amblyopia may be classified as strabismic, refractive (anisometropic and isometropic), deprivational, idiopathic, and mixed types [1, 2]. Studies have investigated involvement of the macula and optical nerve in amblyopia and while some researchers found an increase in the retinal nerve fibre layer (RNFL) thickness or macular thickness, others did not observe any difference [11,12,13,14,15,16,17]

Objectives

Methods

Conclusion