Ocular findings from otoneurological examinations in children with and without dyslexia: a systematic review with meta-analysis

OBJECTIVE: To investigate ocular movements measures of vectoelectro-nystagmography and video-nystagmography in dyslexic children and compare with measures of typical children. METHODS: A systematic review of observational studies comparing the ocular movements differences between dyslexic and typical children with no publication date or language restriction. The literature survey included the bibliographic databases MEDLINE, ScienceDirect, Scopus, Web of Science, SciELO, Lilacs and CENTRAL. Gray literature databases were also searched, including: OpenGrey.eu, DissOnline.de, The New York Academy of Medicine and WorldCat. The meta-analysis was performed using software RevMan 5.3 (Cochran Collaboration). RESULTS: A total of 2375 articles were found of which 113 fell within the inclusion criteria. Among these, 52 were duplicates (found in more than one research source), and 45 articles were selected for reading in full. Thirteen (13) articles were included for analysis and discussion. Meta-analysis showed statistical differences between the two groups for the total number of saccades and duration of fixation. CONCLUSION: The study revealed that children with dyslexia have longer duration of fixation and fewer saccades during ocular movements on vectoelectro-nystagmography and video-nystagmography when compared to children without dyslexia.