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The manifestation of noncycloplegic refractive state in pre-school children is dependent on autorefractor design
1School of Optometry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada. rsuryku@uwaterloo.ca
Insights
Autorefractors for preschool children need designs that relax accommodation. Instruments with distant targets and large working distances provide more accurate hyperopia measurements without cycloplegics.
Area of Science:
- Ophthalmology
- Pediatric Optometry
Background:
- Accurate refractive error assessment in preschool children is crucial for early detection of vision problems.
- Accommodation, the eye's ability to focus, can significantly impact refractive measurements in young children.
Purpose of the Study:
- To investigate factors influencing hyperopic refractive error measurements in preschool children.
- To compare autorefractor performance with and without cycloplegia.
Main Methods:
- Forty-three preschool children (mean age 3.68 years) underwent refractive error testing.
- Multiple autorefractors (Retinomax K plus, Welch Allyn SureSight, PowerRefractor) and retinoscopy were used, with and without cycloplegia.
Main Results:
- Instruments with closer working distances (Retinomax) showed the most underestimation and variability.
- The PowerRefractor with a distant target demonstrated the least underestimation of hyperopia.
- The Welch Allyn SureSight (DAV SureSight) overestimated the refractive state.
Conclusions:
- Autorefractor design for preschool vision screening without cycloplegics requires accommodation stabilization and relaxation.
- Future autorefractor designs should incorporate large working distances and distant fixation targets for improved accuracy.
Purpose:
To investigate the factors that govern the manifestation of hyperopic refractive errors of pre-school children when tested with and without the application of cycloplegics.
Methods:
Forty-three pre-school children (mean age, 3.68 +/- 0.59 years) were tested before and during cycloplegia in the following order: retinoscopy with optical fogging; Retinomax K plus; Welch Allyn SureSight (DAV SureSight), and PowerRefractor. In the case of the PowerRefractor, the children viewed a difference of Gaussian target (0.20 cpd) at 3.5 m in addition to viewing the instrument LED sources.
Results:
Instruments with close working distances (Retinomax) showed the greatest underestimation of hyperopia and the largest variation, followed by the instruments having a greater working distance (PowerRefractor LED view and retinoscopy). The addition of a far target (PowerRefractor difference of Gaussian view) showed the least underestimation, whereas DAV SureSight showed a mean overestimation of the refractive state.
Conclusion:
When autorefractors are applied to vision screening of pre-school children without the use of cycloplegics, autorefractor designs must be developed that both stabilize and relax the child's accommodation. Our results suggest that designs should include large working distances and distant fixation targets.
