Clarification of the onset and cause of intermittent exotropia in children: an eye tracker study

2023 Fiscal Year Final Research Report

• Project/Area Number: 19K12861
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 90140:Medical technology assessment-related
• Research Institution: University of Toyama
• Principal Investigator: Mihara Miharu 富山大学, 学術研究部医学系, 講師 (40377263)
• Project Period (FY): 2019-04-01 – 2024-03-31
• Keywords: 間欠性外斜視 / アイトラッカー / 小児 / サッケード / 眼球運動

Outline of Final Research Achievements

We compared the peak velocity of horizontal saccadic eye movement (saccades) between the children with intermittent exotropia (IXT) group and the children without strabismus group. There was no significant difference in the peak velocity of saccades between the two groups. This result in children differed from the characteristic that adults with IXT had greater peak velocity of horizontal saccade than the adults without strabismus.
Though saccades are eye movements without visual feedback during execution, the characteristics of IXT saccades could be not innate but formed gradually as development. Additionally, children with IXT were found to have weaker saccades of adduction compared to children without strabismus, suggesting a relation between the onset of IXT and the development of convergence.

Free Research Field

眼球運動、斜視、小児眼科

Academic Significance and Societal Importance of the Research Achievements

間欠性外斜視の小児の水平サッケードを解析することで、成人と同様に正常でみられるはずの内転方向のサッケードの優位性が小児期から弱いこと、成人とは異なり、間欠性外斜視のサッケード速度は正常小児と有意な差がないことが判明した。計測が困難なことが多いが、小児期の斜視患者のサッケードを解析することで、成人のサッケードの研究だけではわからない間欠性外斜視の発症やその経過に与える影響の予測に役立つ研究成果であり、今後さらに発展する可能性が高い研究である。