Uma análise do grau de eficiência de leitura e dos efeitos da intervenção espectral em portadores da Síndrome de Meares-Irlen: análise por rastreador da movimentação ocular

Abstract

The aim of this study was to analyze the effects in Reading Efficiency produced by the use of selective spectral Irlen filters in patients with Meares-Irlen syndrome after a follow-up of 12 months. The data was obtained through an eye tracker recording system pre and after theregular use of the Irlen selective spectral filters in daily life activities. The sample consisted of 20 individuals, aged between 10 and 30 years, mean 15.1 years, being 50% males and 50% females. The parameters considered in this study were the number of fixations, reading rate and comprehension while reading a text with grade of difficulty adjusted to the current school level. Irlen Syndrome is a visuoperceptual neurological disorder with reading difficulties associated with photosensitivity, peripheral visual field restriction, difficulty in adapting to contrast (competition between letters and background), difficulties sustaining visual attention and headaches. The diagnostic criteria according to the protocol included a routine eye exam test ( visual acuity, refraction under dinamic and static conditions, biomicroscopy, tonometry, fundoscopy and cover test) and also a functional vision evaluation including contrast testing in 4 phases (photopic and mesopic light stimulation plus glare adjusted to spacial frequencies from 1,5 to 18,0 cycles per degree under increasing luminance and contrast levels), stereospsis and vergence measurements, 2 chromatic tests, orthoptic exam, aberrometry by wave front analysis, binocular vision assessment, optical coherence tomography , visual fields and frequency doubling technology testing. The inclusion of psicophysical tests under controled stimuli presented by a computer aims the analysis of Parvo or/and Magnocellular systems performance due to its well documented influence in spatial, temporal, and contrast processing areas as well as in visual processing skills and reading hability. The obtained data shows that the post-intervention reading efficiency had improved in 95% of cases (19 of 20 cases in the sample). When deployed according to the parameters contained in the protocol, the data shows that 100% of cases reduced the number of fixations, in which 80% of the reduction was also associated to improvement in cross correlation synchronicity between right and left eye movements. As evidenced in this study, the use of selective spectral Irlen filters proved to be a valid treatment due to its effects in reading efficiency levels, cross correlation or oculomotor synchronicity, reading rate, number of fixations. It is also a non-invasive, reversible treatment that presents progressive results, and enhances the intermodal integratingareas so critical to a well structured learning process due to its neuromodulation effects.