Is the anatomy of the macula different in individuals with dyslexia?

Abstract

Purpose: The purpose of this research was to compare the thickness of different retinal layers between dyslexic subjects and controls at the macula by means of optical coherence tomography (OCT). Methods: Each patient underwent a complete ophthalmic examination including macular OCT in both eyes. The thickness of the fovea, four sectors of the parafovea and four sectors of the perifovea were obtained according to the Early Treatment Diabetic Retinopathy Study protocol in the following 13 segmentations: complete retina, outer retina, inner retina, retinal nerve fibre layer (RNFL), ganglion cell layer (GCL), inner plexiform layer (IPL), inner nuclear layer (INL), outer plexiform layer (OPL), outer nuclear layer (ONL), INL + OPL + ONL, IPL + INL, OPL + ONL and ganglion cell complex (RNFL + GCL + IPL). The results of the right and left eyes were independently compared between groups. Results: The thickness in all the four sectors of the parafovea was found significantly higher in the right and in the left eyes in the dyslexic group in the following segmentations: complete retina, inner retina, middle retinal layers and OPL + ONL. Several macular sectors were also thicker in IPL + INL, INL, IPL and ONL in dyslexia. In contrast, no thickness differences between both groups were found in any of the sectors of RNFL, GCL, GCC, or outer retina in any eye. Conclusions: Anatomy of the macula is different in dyslexic and normoreader subjects in middle retinal layers, especially in the parafovea. This fact suggests that the macula may play an important role in the development of dyslexia.