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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
Summary
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.
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