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Mass screening of children for strabismus or ametropia with two-flash photoskiascopy
Insights
Two-flash photoskiascopy effectively screens young children for strabismus and refractive errors like myopia and hyperopia. This method, performed by technicians, aids in early detection of amblyopia-causing conditions.
Area of Science:
- Ophthalmology
- Pediatric Optometry
Background:
- Early detection of visual impairments in children is crucial for preventing amblyopia.
- Traditional screening methods can be time-consuming and require specialized personnel.
Purpose of the Study:
- To evaluate the efficacy of two-flash photoskiascopy for mass screening of young children.
- To assess the method's ability to detect strabismus, high anisometropia, and high ametropias.
Main Methods:
- 169 children aged 1-5 years underwent screening using two-flash photoskiascopy without cycloplegia.
- Photography was conducted by nurses or technicians and analyzed by an optician.
- Sensitivity for refractive errors was validated using an optical eye model.
Main Results:
- The screening identified 5 esotropias, 1 exotropia, and cases of hypermetropic anisometropia.
- Slight refractive errors (myopia and hyperopia) were detected in 19.5% of children.
- 76% of children had normal findings on photographs, with clinical checks confirming accuracy and no false negatives.
Conclusions:
- Two-flash photoskiascopy is a valuable tool for mass infant screening.
- The method, when performed by technicians, aids in identifying strabismus and ametropias that can lead to amblyopia.
Unlabelled:
169 non-selected 1-5 year-old children (338 eyes) were screened by two-flash photoskiascopy with an autofocus camera for strabismus, high anisometropia and high ametropias without cycloplegia. The photography was performed by nurses or technicians and the photographs were analyzed by an optician. The sensitivity of the method for the refractive errors was tested with an optical demonstration eye.
Findings:
5 esotropias, 1 exotropia, 1 straight-eyed hypermetropic anisometropia of 4 diopters; 1 false positive high hyperopia (of +2.5 diopters) of both eyes. The examination of the photographs showed slight refractive errors in 33 cases (66 eyes; 19.5%): two of them of symmetrical myopia of -1.0 and -1.75 diopters and 31 of symmetrical hyperopia of +0.25 to +4.25 diopters in retinoscopy. 128 cases (256 eyes; 76%) were normal on the photographs. Of these, 37 non-selected cases (74 eyes) were checked clinically and were symmetrical cases of -1.0 to +3.25 diopters on retinoscopy. No false negative cases appeared among these control cases. 2,4% of the photographs failed technically or because of noncooperation of the children. Two-flash photoskiascopy, performed by technicians or nurses provides a valuable tool for mass screening of infants for strabismus and/or ametropia causing amblyopia.
