METHODS: Twenty-seven right eyes (24 females and 3 males) of 27 myopic schoolchildren aged between 13 and 15 years were included in this study. The measurements of central refraction, peripheral refraction (between 35° temporal and 35° nasal visual field in 5° steps), and lag of accommodation were conducted using the Grand-Seiko WR-5100K open-field autorefractometer initially without correction (WC), followed by with correction using four different addition powers of Proclear® multifocal D-Design contact lens in random sequence. Axial length was measured using a handheld probe ultrasound A-scan (Tomey AL-2000).
RESULTS: The relative peripheral refractive error showed high hyperopic defocus of +1.08 ± 1.24 D at 35° nasal and +1.06 ± 1.06 D at 35° temporal visual field WC. All Proclear multifocal contact lenses (MFCLs) decreased the peripheral hyperopic defocus with increasing addition powers (F [2.938, 47.001] = 13.317, P < 0.001). However, only +3.00 D addition and +3.50 D addition (P = 0.001) could invert the peripheral hyperopic defocus into peripheral myopic defocus. Apart from that, the +3.00 D addition lens showed the lowest lag of accommodation (+1.10 ± 0.83 D) among the other MFCL adds (P = 0.002).
CONCLUSION: A +3.00 D addition Proclear MFCL is the optimal addition power that can invert the pattern of peripheral hyperopic defocus into myopic defocus.
METHODS: Cycloplegic (1% cyclopentolate) autorefraction was performed on 38, 811 children aged 5 and 15 in population-based samples at eight sites in the Refractive Error Study in Children (RESC). Refractions (right eye) were categorized as myopic (≤-0.5 D), emmetropic (>-0.5 to ≤+0.5 D), mildly hyperopic (>+0.5 to ≤+2.0 D and hyperopic (>+2.0 D).
RESULTS: At five sites (Jhapa - rural Nepal, New Delhi - urban India, Mahabubnagar - rural India, Durban - semi-urban South Africa and La Florida - urban Chile), there was <20% myopia by age 15. Mild hyperopia was the most prevalent category at all ages, except for Mahabubnagar where emmetropia became the marginally most prevalent category at ages 14 and 15. At the other sites (Gombak - semi-urban Malaysia, Shunyi - semi-rural China and Guangzhou - urban China), there was substantial (>35%) myopia by age 15. At these sites, mild hyperopia was the most prevalent category during early childhood, and myopia became the predominant category later. In Gombak district and Guangzhou, emmetropia was a minor category at all ages, with myopia increasing as mild hyperopia decreased. In Shunyi district, emmetropia was the most prevalent category over the ages 11-14.
CONCLUSION: Emmetropia was not the predominant outcome for refractive development in children. Instead, populations were predominantly mildly hyperopic or substantial amounts of myopia appeared in them. This suggests that mild hyperopia is the natural state of refractive development in children and that emmetropia during childhood carries the risk of subsequent progression to myopia.
OBJECTIVE: To determine the prevalence of visual impairment and amblyopia in Malaysian preschool children.
METHODOLOGY: A cross-sectional, population-based study was conducted on children aged four to six years from 51 participating kindergartens in the district of Segamat, Johor, Malaysia from 20 March 2016 to 6 April 2016. All subjects had initial eye screening consisting of LogMar visual acuity, orthoptics examination and Spot vision screener assessment. Subjects who failed the initial eye screening were invited for a formal eye assessment consisting of cycloplegic refraction and a comprehensive ocular examination. Definitions of visual impairment and amblyopia were based on the Multi-Ethnic Pediatric Eye Disease Study criteria.
RESULTS: A total of 1287 children were recruited. Mean subject age was 5.03 (SD:0.77) and males represented 52.3% of subjects. Subjects by ethnicity were Malay (54.8%), Chinese (27.7%), Indian (15.6%) and Orang Asli (1.9%). Formal eye assessment was required for 221 subjects and 88.8% required ophthalmic intervention. Refractive error, representing 95.4% of diagnosed ocular disorders, comprised of astigmatism (84%), myopia (9%) and hypermetropia (6.9%). With-the-rule astigmatism was present in 93.4% of the subjects with astigmatism. Visual impairment was present in 12.5% of our subjects, with 61% having bilateral visual impairment. Of the subjects with visual impairment, 59.1% had moderate visual impairment. The prevalence of amblyopia was 7.53%, and 66% of the amblyopic subjects had bilateral amblyopia.
CONCLUSION: Our study highlights an urgent need for initiation of preschool vision screening in Malaysia.