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Screening of infants for strabismus and refractive errors with two-flash photorefraction with and without cycloplegia
Insights
Two-flash photorefraction effectively screens young children for strabismus and refractive errors. Cycloplegia enhances sensitivity for detecting refractive errors, particularly hyperopia, in pediatric eye exams.
Area of Science:
- Ophthalmology
- Pediatric Optometry
- Vision Science
Background:
- Early detection of strabismus and refractive errors is crucial for preventing amblyopia.
- Photorefraction offers a non-invasive method for assessing vision in infants and young children.
- Cycloplegia is often used to achieve accurate refractive error assessment in pediatric populations.
Purpose of the Study:
- To evaluate the sensitivity and accuracy of two-flash photorefraction for detecting strabismus and refractive errors in young children.
- To compare the efficacy of two-flash photorefraction with and without cycloplegia.
- To determine the feasibility of using this method for large-scale pediatric vision screening.
Main Methods:
- Two-flash photorefraction screening was performed on children aged 0.5 to 1 year.
- Refractive error assessment was conducted both with and without cycloplegia.
- Clinical examinations were used to validate the photorefraction findings.
- An optical demonstration eye was used to test the method's sensitivity to refractive errors.
Main Results:
- Two-flash photorefraction demonstrated high sensitivity for strabismus detection, with no false positives or negatives.
- The method was significantly more sensitive in detecting refractive errors when cycloplegia was used.
- Significant hyperopia (e.g., +5.25 D) was underestimated without cycloplegia.
- Good correlation of refractive results was observed with cycloplegia, with some overlap in emmetropic and moderate hyperopic cases.
Conclusions:
- Two-flash photorefraction is a simple and effective screening tool for strabismus and refractive errors in infants and young children.
- Cycloplegia is recommended for accurate refractive error assessment using this method, especially for hyperopic cases.
- The underestimation of symmetrical hyperopia without cycloplegia should be considered in screening protocols.
Abstract:
35 1/2-year-old and 31 1-year-old children were screened by two-flash photorefraction for strabismus and refractive errors with and without cycloplegia. The sensitivity of the method to detect refractive errors was tested with an optical demonstration eye. All the children were examined clinically to compare the sensitivity of the method. Every child co-operated with the photography, but 4 children did not co-operate in the clinical examination and were thus excluded from the refractive material, as were also two cases of esotropias which were found. There were no false positive or negative strabismus cases. The total refractive material consisted of 120 eyes. The method was clearly more sensitive for refractive errors with cycloplegia. Even one hyperopia of +5.25 D(OD) and +6.0 D(OS) was underestimated without cycloplegia. In the material there were no cases of anisometropia of over 1.0 D in spherical equivivalent that would cause a potential risk for amblyopia. A rather good correlation of refractive results existed with the method in cycloplegia. With partial overlapping of emmetropic and moderate hyperopic cases. The screening of children aged 1/2-1 year with two-flash photorefraction is simple to perform. The underestimation of symmetrical hyperopias should be accepted when cycloplegia is not used. Only one successful photograph of each child is necessary for the interpretation.
