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Convergence insufficiency and accommodative insufficiency in children.

Amélia F Nunes1,2,3,4, Pedro M L Monteiro5,6,7,8, Francisco B P Ferreira5,6,7,8

  • 1Department of Physics, University of Beira Interior, 6200, Covilhã, Portugal. amnunes@ubi.pt.

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Summary

Approximately 10% of schoolchildren experience convergence insufficiency or accommodative insufficiency, leading to visual discomfort. Early evaluation of binocular vision is crucial for addressing symptoms like headaches and poor concentration during near work.

Keywords:
Accommodative insufficiencyChildrenConvergence insufficiencyNormal binocular visionVisual discomfort

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Area of Science:

  • Ophthalmology
  • Pediatric Optometry
  • Public Health

Background:

  • Convergence insufficiency (CI) and accommodative insufficiency (AI) are primary causes of visual complaints during near work.
  • These conditions can significantly impair visual performance and comfort in children.
  • Understanding their prevalence in schoolchildren is vital for developing targeted interventions.

Purpose of the Study:

  • To determine the prevalence of CI and AI in 5th and 6th-grade students in inland Portugal.
  • To assess the impact of CI and AI on the quality of life through visual symptom analysis.

Main Methods:

  • A cross-sectional study involving 372 schoolchildren (ages 10.9 ± 0.9 years).
  • Comprehensive assessment of refractive error and binocular vision, including accommodative parameters.
  • Quantification of visual symptoms using the Portuguese version of the Convergence Insufficiency Symptom Survey (CISS).

Main Results:

  • The prevalence of definite Convergence Insufficiency (CI) was 2%, rising to 6.8% when including clinically significant cases.
  • Accommodative Insufficiency (AI) affected 10% of students, with 3% experiencing both CI and AI concurrently.
  • Higher symptom scores were reported in children with AI compared to those with CI.

Conclusions:

  • Both CI and AI affect approximately 10% of the studied student population.
  • Visual discomfort is prevalent among adolescents with these conditions.
  • Evaluation of binocular vision quality is recommended for asthenopia symptoms like headaches and reduced concentration during near tasks.