Adeline Yang

Differences in Prevalence of Refractive Errors in Young Asian Males in Singapore between 1996-1997 and 2009-2010

Abstract Purpose: To determine the differences in prevalence rates of refractive errors in young Singaporean males over a 13-year period between 1996–1997 and 2009–2010 Methods: Non-cycloplegic autorefraction data were obtained in a survey of 15,085 young male subjects (mean age 19.5 ± 1.4 years, range 16–25 years) in 1996–1997 using a Nikon NRK-8000 autorefractor. A second survey of 28,908 male subjects (mean age 19.8 ± 1.2 years, range 17–29 years) was conducted in 2009–2010 using a Huvitz MRK-3100 autorefractor. Results: The overall prevalence of myopia (spherical equivalent, SEq, worse than −0.5 diopters, D) was similar in 2009–2010 (81.6%) and 1996–1997 (79.2%; odds ratio 1.38, 95% confidence interval 1.31–1.46; p < 0.001). The prevalence of high myopia (SEq worse than −6.0D) increased from 13.1% in 1996–1997 to 14.7% in 2009–2010 (p < 0.001). The prevalence of refractive astigmatism increased significantly from 41.4% in 1996–1997 to 50.9% in 2009–2010 (p < 0.001). Conclusions: Our results show that the prevalence of myopia and high myopia remained high and the prevalence of astigmatism increased in young male adults in Singapore over a 13-year period after controlling for age, education and ethnicity.

Choroidal thickness and high myopia: a case-control study of young Chinese men in Singapore.

To determine the distribution of choroidal thickness (CT) and ocular factors associated with CT in high myopic eyes in comparison with emmetropic eyes of young healthy adults.

Peripapillary choroidal thickness in young Asians with high myopia.

PURPOSE To describe the topography and predictors of peripapillary choroidal thickness (PPCT) in highly myopic eyes of young, healthy, Asian subjects. METHODS A total of 870 young male subjects aged 21.63 ± 1.15 years were recruited from the Singapore military. Choroidal imaging was performed using enhanced depth imaging (EDI) spectral-domain optical coherence tomography (SD-OCT). Peripapillary choroidal thickness was manually measured at eight locations around the optic disc. RESULTS We analyzed 448 subjects with high myopia (defined as spherical equivalent [SE] worse than -6.0 diopters [D]) and 116 with emmetropia (SE > -0.5 and < 0.5 D). The mean SE was -8.52 ± 1.20 D for the high-myopic group, and 0.11 ± 0.24 D for the emmetropic group. The mean peripapillary choroid was significantly thinner (142.62 ± 43.84 μm) in high myopes compared with emmetropes (181.90 ± 46.43 μm, P < 0.001). Likewise, PPCT showed further decrease with increase in degree of myopic refractive error. Distribution of PPCT showed a markedly different pattern in high-myopic eyes (thickest superiorly) and emmetropic eyes (thickest temporally). However, peripapillary choroid in both the groups was thinnest at the inferior location. Among the ocular factors studied, axial length, IOP, presence of posterior staphyloma, and chorioretinal atrophy were the factors significantly associated with PPCT. CONCLUSIONS Highly myopic eyes have significantly thinner peripapillary choroid and showed different distribution of thickness, compared with emmetropes. Axial length, IOP, and presence of posterior staphyloma and chorioretinal atrophy significantly influence PPCT and should be taken into consideration during clinical interpretation of PPCT measurement.

Choroidal thickness does not predict visual acuity in young high myopes

To investigate the influence of choroidal thickness (CT) on visual acuity (VA) in young persons with extremely high myopia.

Correlation of structural and electrophysiological changes in the retina of young high myopes

Despite a high prevalence of myopia among young East Asian adults, there is a lack of data on the myopic retina structure‐function relationship in this group. We examined the association between optical coherence tomography (OCT) and electroretinogram (ERG) measurements in highly myopic young Asian adults to provide this information and also determined if OCT can be used as an alternative screening tool to assess retinal function in young myopic adults.

Is Myopia Affected By Near Work, Outdoor Activities And/Or Level Of Education?

Introduction Near work has always been associated with the influence of myopia (Ip JM, et al., 2008, Saw SM, et al., 2001 & 2002, Goss DA, et al., 2000). It has been shown to affect the progression of myopia. In this study, we aimed to determine if there is a relationship between outdoor activities and myopia, as the prevalence of myopia seems to be lower in children who are more active outdoor. (Rose KA, et al., 2008, Dirani M, et al., 2009, Jones LA, et al., 2007). In addition, we also aimed to establish if the level of education affects myopia prevalence.