Abstract
Purpose :
The American Association for Pediatric Ophthalmology and Strabismus (AAPOS) has vision screening guidelines to detect amblyopia risk factors (ARFs) in preschool children. However, studies have shown susceptibility of even older children to amblyopia. In this study, we determine the prevalence of ARFs in an urban school population and study the association with best corrected visual acuity (BCVA) based on non-cycloplegic manifest refraction.
Methods :
During 2016/17, we examined students who failed school-based vision screenings in 41 Baltimore City schools. Children older than 48 months were included. We calculated the prevalence of ARFs according to 2013 AAPOS guidelines: astigmatism > +1.5 D, hyperopia > +3.5 D, anisometropia > 1.5 D, and myopia > -1.5 D. We evaluated the association between ARFs, excluding anisometropia, and BCVA in right eyes of the study population; and conducted sensitivity analyses with left eyes and children younger than 8 years.
Results :
Of 2174 children, 795 (37%) had one ARF and 325 (15%) had 2 or more: 77 (4%) with hyperopia, 678 (31%) with astigmatism, 224 (10%) with anisometropia, and 525 (24%) with myopia. ARFs were more prevalent in younger children (p = 0.02) and boys (54% vs. 49%, p = 0.05). Chances of failing photoscreener testing were 52% in children with no ARF, 77% with 1 or 2, 87% with 3 and 100% with 4 (p-trend < 0.001). Of children with ARF(s), only 83 (7%) were wearing eyeglasses, while 1039 (93%) needed prescriptions. There were 44 children with impaired vision (BCVA ≤ 20/40) in the right eye. After adjusting for age, sex and eyeglasses wearing, impaired vision was associated with hyperopia (PrR = 19, p < 0.001), astigmatism (PrR = 3.6, p < 0.001) and myopia (PrR = 3.4, p < 0.001). The strong association with hyperopia was maintained with both sensitivity analyses.
Conclusions :
More than half of children in an urban school population who failed vision screening have one or more refractive ARFs, while only 7% of them were wearing eyeglasses, highlighting their pressing need for eye care. Children with ARFs, particularly hyperopia, had reduced visual acuity after manifest refraction, indicating they have may visual loss not fully correctable with eyeglasses. This finding needs further exploration.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.