METHODS: A total of 8500 self-administered questionnaires were distributed in eight selected secondary schools. The results were analysed using descriptive statistics.
RESULTS: A total of 2474 (29%) completed questionnaires were collected. The mean age of the respondents was 14.8 ± 1.5 years, and approximately 7.2% were CL wearers. The majority of the wearers were females (76.0%) and wore soft CLs (92.2%). Cosmetic purposes (58.1%) and comfort (24.6%) were the main reasons for wearing CLs. Many of the respondents purchased their lenses from optical shops (50.1%) and beauty accessory shops (15.6%), and approximately 10% did not disinfect their lenses properly. Regarding knowledge about CL care, approximately 56% of the respondents responded correctly.
CONCLUSION: Half of the respondents do not have sufficient knowledge about the risks of wearing CLs. Thus, aggressive public health education aimed at teenagers is needed to prevent improper CL usage.
PATIENTS AND METHODS: A total of 70 children with myopia (aged 8-9 years old) were recruited. A total of 45 children were fitted with Ortho-K, and 25 were fitted with SVS. The PEL and axial length (AL) were measured by using MRI 3-Tesla, whereas central and peripheral refraction (PR) measurements were conducted at ±30 degrees horizontally with nasal (N) and temporal (T) intervals of 10°, 20°, and 30° and with an open field autorefractometer (WAM-5500 Grand Seiko). All the measurements were conducted at the baseline and 12 months.
RESULTS: The MRI analysis indicates that at 12 months, the SVS group showed more elongation of the PEL and AL at all eccentricities than the Ortho-K group did (p < 0.05). The Ortho-K group only showed significant PEL elongation beyond 20 degrees at N20, N30, T20, and T30 (p < 0.05); however, a significant reduction in the AL was detected in the center AL, N10, and T10 (p < 0.05). All eccentricities in the relative PR of the Ortho-K group were significantly more myopic than at the baseline (p < 0.05), whereas in the SVS group, all eccentricities in the relative PR were shown to be significantly more hyperopic than at the baseline (p < 0.05). The PEL and PR showed negative correlations at 12 months in the Ortho-K group.
CONCLUSION: MRI analysis can be utilized to describe changes in PEL in myopic children. It appears that as myopia progressed in Ortho-K lens wearers, the PEL increased by a greater amount than the AL did; thus, the retina was reshaped to become increasingly oblate and to display peripheral myopic defocus.
METHODS: This is a cross sectional study. Myopic children who had been wearing ortho-K and SVSs for 12 months were recruited, and the questionnaires were distributed online. The PREP scores were obtained using a summary scoring method. The Shapiro-Wilk test was used to determine data normality. Unpaired t-test was performed for normally distributed data, and the Mann-Whitney test for non-normally distributed data. P
METHODS: Healthy school children aged < 10 years were invited to take part in this cross-sectional study. Refraction and best-corrected distance visual acuity (BCDVA) were determined using cycloplegic refraction and a logarithm of the minimum angle of resolution (logMAR) chart, respectively. All children underwent MRI using a 3-Tesla whole-body scanner. Quantitative eyeball measurements included the longitudinal axial length (LAL), horizontal width (HW), and vertical height (VH) along the cardinal axes. Correlation analysis was used to determine the association between the level of refractive error and the eyeball dimensions.
RESULTS: A total of 70 eyes from 70 children (35 male, 35 female) with a mean (standard deviation [SD]) age of 8.38 (0.49) years were included and analyzed. Mean (SD) refraction (spherical equivalent, SEQ) and BCDVA were -2.55 (1.45) D and -0.01 (0.06) logMAR, respectively. Ocular dimensions were greater in myopes than in emmetropes (all P < 0.05), with no significant differences according to sex. Mean (SD) ocular dimensions were LAL 24.07 (0.91) mm, HW 23.41 (0.82) mm, and VH 23.70 (0.88) mm for myopes, and LAL 22.69 (0.55) mm, HW 22.65 (0.63) mm, and VH 22.94 (0.69) mm for emmetropes. Significant correlations were noted between SEQ and ocular dimensions, with a greater change in LAL (0.46 mm/D, P < 0.001) than in VH (0.27 mm/D, P < 0.001) and HW (0.22 mm/D, P = 0.001).
CONCLUSIONS: Myopic eyeballs are larger than those with emmetropia. The eyeball elongates as myopia increases, with the greatest change in LAL, the least in HW, and an intermediate change in VH. These changes manifest in both sexes at a young age and low level of myopia. These data may serve as a reference for monitoring the development of refractive error in young Malaysian children of Chinese origin.
METHODS: A total of eighty-four data samples were extracted from forty-two myopic Malay school children. Measurements of the central corneal thickness (CCT), corneal curvature, corneal diameter, and axial length were measured using Lenstar LS900, a non-contact optical biometer. Data were later stratified by the spherical equivalent refraction (SER) into a low myopic group and a moderate myopic group, and paired t-test were employed to determine the differences in the corneal characteristics between these two groups. Univariate and multivariate linear regressions were performed to identify factors that are significantly associated with axial length.
RESULTS: There was no significant difference in the CCT, corneal curvature and corneal diameter between the low myopic group and the moderate myopic group (t82=0.015, P=0.99), (t82=-0.802, P=0.43) and (t82=-0.575, P=0.57), respectively. Pearson univariate correlation analysis found that axial length significantly correlated with corneal curvature (r=-0.765, P<0.001) and corneal diameter (r=0.614, P<0.001) but no significant correlation found with CCT (r=0.046, P=0.68). Multiple regression analysis showed that axial length was significantly associated with a flatter corneal curvature (P<0.001), older age (P<0.001) and larger corneal diameter (P=0.02).
CONCLUSION: This study reported the corneal characteristics in myopic Malay school children and its associations with axial length. Results of this study can serve as a reference value for the myopic Malay schoolchild population.