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Repeatability of ARK-30 in a pediatric population

Laura Hernandez-Moreno1, Ana Vallelado-Alvarez2, Raul Martin3

  • 1Optometry Research Group, IOBA Eye Institute, School of Optometry, University of Valladolid, Valladolid, Spain; Vision Rehabilitation Lab, Department of Physics and Optometry, University of Minho, Braga, Portugal.

Indian Journal of Ophthalmology
|August 22, 2018
PubMed

Insights

The ARK-30 handheld autorefractor shows poor repeatability without cycloplegia in children. With cycloplegia, it offers better agreement with retinoscopy for refractive error estimation but doesn't replace it.

Area of Science:

  • Ophthalmology
  • Optometry
  • Pediatric Eye Care

Background:

  • Accurate refractive error assessment is crucial for pediatric eye care.
  • Handheld autorefractors offer potential for portable vision screening.
  • Evaluating the accuracy and repeatability of devices like the ARK-30 is essential.

Purpose of the Study:

  • To assess the repeatability and agreement of the ARK-30 handheld autorefractor compared to retinoscopy.
  • To evaluate performance under both cycloplegic and noncycloplegic conditions in children.

Main Methods:

  • A cross-sectional, masked study involving 30 children (mean age 6.7 years).
  • Three consecutive measurements using the ARK-30 (with and without cycloplegia) and retinoscopy were performed.
  • Bland-Altman analysis was used to compare measurements in conventional and vector notations.

Main Results:

  • ARK-30 measurements without cycloplegia showed lower values and statistically significant differences from retinoscopy.
  • Repeatability was significantly better under cycloplegic conditions (Sph LoA: -0.66 to +0.69 D, SE LoA: -0.66 to +0.65 D) compared to noncycloplegic conditions.
  • Cycloplegic autorefraction measures were not statistically different from retinoscopy measures.

Conclusions:

  • The ARK-30 exhibits low repeatability and a tendency towards minus overcorrection in children without cycloplegia.
  • While cycloplegia improves ARK-30's repeatability and agreement with retinoscopy, it remains an estimation tool, not a substitute for gold standard retinoscopy.
Abstract

Keywords:
Autorefractionchildren refractive assessmentcycloplegiarepeatabilityretinoscopy

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