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Variability in Objective Refraction for Persons with Down Syndrome.

Jason D Marsack1, Ayeswarya Ravikumar, Julia S Benoit

  • 1*PhD, FAAO †PhD ‡OD, PhD, FAAO University of Houston College of Optometry, Houston, Texas (all authors); and Texas Institute for Measurement, Evaluation and Statistics, University of Houston, Houston, Texas (JSB).

Optometry and Vision Science : Official Publication of the American Academy of Optometry
|March 14, 2017
PubMed
Summary
This summary is machine-generated.

Individuals with Down syndrome (DS) show significantly higher variability in autorefraction measurements compared to controls. This suggests greater uncertainty in objective refractive error assessment for the DS population, particularly influenced by J45.

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Area of Science:

  • Ophthalmology
  • Genetics
  • Biomedical Engineering

Background:

  • Down syndrome (DS) is a genetic disorder associated with ocular abnormalities and cognitive impairments.
  • These conditions can potentially influence the accuracy and reliability of refractive error measurements.
  • Understanding variability in autorefraction is crucial for effective clinical management of individuals with DS.

Purpose of the Study:

  • To compare the variability of autorefraction measurements between individuals with and without Down syndrome.
  • To identify factors contributing to refractive error variability in the Down syndrome population.
  • To assess the reliability of objective refraction techniques in individuals with DS.

Main Methods:

  • Grand Seiko autorefraction was performed on 139 subjects with DS and 138 controls.
  • Three refraction measurements per eye were analyzed using power vector notation (M, J0, J45).
  • Differences in refractive components (ΔM, ΔJ0, ΔJ45) and total dioptric difference were calculated.

Main Results:

  • Subjects with DS exhibited significantly greater median dioptric strength and dioptric difference compared to controls (P < .001).
  • Nearly twice as many control eyes (97.1%) had a dioptric difference ≤0.50D compared to DS eyes (59.3%).
  • The J45 component of refractive error was found to be a significant contributor to the observed variability.

Conclusions:

  • Autorefraction in individuals with Down syndrome demonstrates 2.8 times greater median total dioptric difference than in controls.
  • This indicates increased potential uncertainty in objective refractive error assessment for the DS population.
  • The variability is significantly influenced by the J45 component of the refractive error.