RESUMO
BACKGROUND: Since ametropia is a leading cause of amblyopia refractive screening of preschool children is recommended. Measurement of refraction using tabletop autorefractors can be difficult or impossible due to lack of cooperation in this age group. The intention of the present study is to evaluate the use of a new handheld autorefractor for screening in kindergartens. METHODS: A total of 216 children aged 3.5-4.5 years were examined without cycloplegia using the handheld autorefractor (SureSight, Welch Allyn) in their kindergartens. RESULTS: Using the test device the majority of the examined eyes showed mild hyperopia (on average +1.18+/-0.87 dpt spherical equivalent) and mild astigmatism (on average 0.60+/-0.46 dpt cylinder power). The reproducibility of repeated autorefractor readings was higher for cylinder power and axis than for the spherical equivalent. Autorefractor readings of 55 eyes could be compared with the results of cycloplegic retinoscopy. The results were similar between the two measurements with differences of no more than 0.5 dpt in 18.2% for the spherical equivalent, in 82.1% for cylinder power, and in 66.6% for axis (weighted axis difference). There was adequate cooperation in 99.5% of the children. CONCLUSION: The handheld autorefractor proved an accuracy of measurement comparable to that of conventional tabletop autorefractors for cylinder power and axis with limitations in accuracy for the spherical equivalent. Validity and threshold values for relevant abnormalities are to be evaluated in further studies. By the high cooperation rate the instrument proved useful for screening examinations in preschool children.
