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Using Small Samples to Evaluate Normative Reference Ranges for Retinal Imaging Measures.

William H Swanson, Brett J King1, Douglas G Horner1

  • 1Indiana University School of Optometry, Bloomington, Indiana *wilswans@indiana.edu.

Optometry and Vision Science : Official Publication of the American Academy of Optometry
|February 26, 2019
PubMed
Summary
This summary is machine-generated.

Retinal nerve fiber layer (RNFL) deviation maps can falsely flag healthy eyes for defects. This study reveals how variability in RNFL shape causes these wedge patterns, aiding early detection in normative database development.

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Area of Science:

  • Ophthalmology
  • Medical Imaging
  • Biostatistics

Background:

  • Retinal nerve fiber layer (RNFL) deviation maps are crucial for diagnosing optic neuropathies.
  • Existing methods may misclassify healthy eyes due to inherent variability in RNFL thickness and shape.
  • Early identification of false positives in normative databases is essential for accurate clinical interpretation.

Purpose of the Study:

  • To investigate the cause of false-positive wedge defects in RNFL deviation maps of healthy eyes.
  • To propose a method for early detection of such issues during normative database development.
  • To improve the accuracy of RNFL analysis in clinical and research settings.

Main Methods:

  • RNFL thickness was measured in 60 healthy young adults and 30 healthy older adults.
  • Deviation maps were generated using RNFL shape variability data from subsets of participants.
  • Between-subject variability in RNFL shape was assessed across different age groups and eyes.

Main Results:

  • Significant between-subject variability in RNFL shape led to wedge patterns in deviation maps for a substantial percentage of healthy eyes (up to 58% in one cohort).
  • These wedge patterns were observed across different groups of young and older healthy adults.
  • The findings indicate that RNFL shape variability is a common cause of false positives.

Conclusions:

  • RNFL thickness map evaluation in healthy individuals is sufficient to identify between-subject variability.
  • This variability can manifest as wedge patterns in RNFL deviation maps, affecting many healthy eyes.
  • The study highlights the need to account for RNFL shape variability in normative database construction to prevent misdiagnosis.