Incidence and progression of astigmatism in Singaporean children

PURPOSE: This study investigated the incidence and progression, as well as factors associated with changes in astigmatism in school children. METHODS: This was a prospective cohort study. Children 7 to 9 years of age, of Chinese, Malay, and Asian Indian ethnicity, were examined annually over a 4-year period. Cycloplegic autorefraction was performed. A questionnaire was used to evaluate risk factors for incidence and progression of astigmatism. RESULTS: The cumulative 3-year incidence rate of astigmatism was 33.6% (cylinder power of 0.5 D or worse) or 11.5% (cylinder power of 1.0 D or worse). Myopic children had a higher incidence rate of astigmatism than nonmyopes (P <0.001). The mean J0 change per year was 0.012 D (95% CI: 0.007-0.018), whereas J45 did not show a significant change each year (mean, 0.001 D per year). Chinese children had greater worsening of J0 per year (P <0.001). Girls also had significantly greater progression of J0 than did boys (P <0.001). Similarly, myopia at baseline (P <0.001) and the hours of computer use (P=0.049) were associated with a greater progression rate of J0. J0 tended to improve in children with compound hyperopic astigmatism, worsen in children with compound myopic astigmatism, and remain stable in mixed astigmatics. CONCLUSIONS: Although there was minimal progression of astigmatism in school age children (0.44-0.53 D) over this period of follow-up, incident cases of astigmatism (>1.0 D) were not uncommon. The progression rate of astigmatism was affected by the ethnicity, presence of myopia, axis, and subtype of astigmatism.     

Factors related to the progression of myopia in Singaporean children.

PURPOSE: To examine the possible factors related to the progression of myopia in Singapore children. METHODS: One hundred fifty-three Singapore children aged 6 to 12 years were recruited to participate in a concurrent cohort study of the risk factors for the progression of myopia. Socioeconomic status, outdoor activity, and near-work activity were documented in a face-to-face clinic interview. The changes in cycloplegic subjective refraction and autorefraction were ascertained with the use of a Nidek ARK 900 over a 2-year period. RESULTS: The average rate of progression of myopia as measured by subjective refraction was -0.59 D per year (95% confidence interval -0.52, -0.66). Younger children and children who were more myopic at the beginning (refractive error worse than -2.0 D) of the study had higher myopia progression rates. CONCLUSIONS: Myopia progression was faster for younger children and for children who had more severe myopia at baseline. Socioeconomic status and near-work activity were not related to myopia progression.     

Temporal variations in myopia progression in Singaporean children within an academic year.

PURPOSE: Excessive nearwork is believed to be associated with myopia development and progression. To investigate this further, we studied refractive error changes and their correlation with nearwork in a cohort of grade school children in Singapore. METHODS: Cycloplegic autorefraction was performed 5 times over 10 months on 168 children aged 7, 9, and 12 years who were further divided into myopic and nonmyopic subgroups based in their initial refractive errors. Information about nearwork was obtained through diaries filled out over 24 h at the commencement of the study. RESULTS: Myopia progression was high (overall mean: -0.87 D per year) and largely linear throughout the year, but significantly higher rates were seen after the final school examinations in 7-year-old myopes and nonmyopes. Overall, myopic groups exhibited higher progression rates than nonmyopic groups, although 33.6% of subjects from the latter groups had become myopic by the end of the study. Nearwork scores derived from the diaries were generally not well correlated with overall myopia progression. CONCLUSIONS: The tendency for myopia progression rates to increase after the final school examinations in 7-year-olds is interpreted as a delayed effect of the intense nearwork associated with preparing for them. The timing of nearwork-diary data collection at the beginning of the study could be responsible for the poor correlation between these data and overall myopia progression rates.     

A cohort study of incident myopia in Singaporean children

PURPOSE: To determine the risk factors of incident myopia in a school-based cohort study in Singaporean children. METHODS: A 3-year prospective cohort study was conducted in Singaporean school children aged 7 to 9 years in three schools at entry. Chinese children without myopia at baseline (n = 994) were included in the analysis. The main outcome was incident myopia, defined as spherical equivalent (SE) at least -0.75 D based on cycloplegic autorefraction. Other definitions of incident myopia, at least -0.5 D and at least -1.0 D, were also assessed. RESULTS: After controlling for school, age, gender, income, reading in books per week and intelligence quotient (IQ) test scores, we found the relative risk (RR) of incident myopia defined as -0.75 D to be 1.55 (95% confidence interval [CI] 1.18-2.04) for two versus no myopic parents. The multivariate RR of myopia for IQ in the third versus first tertile was 1.50 (95% CI, 1.19-1.89). However, the RR of incident myopia was 1.01 (95% CI, 0.97-1.05) for every unit increase in books read per week. Similar results were obtained with definitions of -0.5 and -1.0 D for incident myopia. CONCLUSIONS: These data provide new prospective evidence of essential links between parental myopia, IQ scores and subsequent myopia development. However, reading in books per week was not associated with incident myopia.     

Prevalence, incidence, and progression of myopia of school children in Hong Kong

PURPOSE: To determine the prevalence, incidence, and progression of myopia of Chinese children in Hong Kong. METHODS: A cross-sectional survey was initially conducted. A longitudinal follow-up study was then conducted 12 months later. RESULTS: A total of 7560 children of mean age 9.33 (95% confidence interval [CI] = 9.11-9.45; range, 5-16) participated in the study. Mean spherical equivalent refraction (SER) was -0.33 D (SD = 11.56; range, -13.13 to +14.25 D). Myopia (SER 相似文献   

Longitudinal study of anisometropia in Singaporean school children

PURPOSE: The purpose of this study was to document the incidence rates of anisometropia, year-by-year prevalences, changes in the intereye difference in spherical equivalent (SE), and its association with myopia progression and axial length changes in a cohort of Singaporean school children. METHODS: This is a prospective cohort study of Singaporean school children (n = 1979) aged 7 to 9 years who were examined annually with cycloplegic refraction and ultrasonography over a 3-year period. RESULTS: In the 1908 children without anisometropia at commencement, the 3-year cumulative incidence rate of anisometropia (difference in SE at least 1.0 D) was 144 (7.55%; 95% CI: 6.42-8.85). The mean intereye difference in SE in all children at baseline was 0.29 +/- 0.46 D (SD: 0.46) and increased to 0.44 D (0.59) on the last examination. On the initial examination, 3.6% (95% CI: 2.8-4.4) or 71 children had anisometropia. Of the 59 of 71 children who completed all examinations, only 3 (5.1%) had an increase in the intereye difference in SE by at least 0.5 D, whereas 2 (3.4%) had a decrease of at least 0.5D. The mean intereye difference in SE was stable between visits. The change in intereye difference in SE correlated with the change in intereye axial length (r = 0.43). Compared with the isometropic children, each eye of the anisometropic children had a higher rate of progression of myopia. CONCLUSIONS: The 3-year incidence of anisometropia was 7.55% in these young Singaporean children. Although the frequency of anisometropia increased with time, the difference in SE between eyes tended to remain stable.     

Peripheral optical quality and myopia progression in children

Background

To investigate the peripheral optical quality and its relationship with axial elongation, myopic progression in Japanese children.

Methods

Twenty-nine Japanese children, ages 10 to 12 years old, with baseline refraction from +0.75D to ?5.5 D, were included and followed for 9 months. The central and peripheral point spread functions (PSFs; 0°, 10°, 20°, 30° nasally) were obtained at 0.25 D steps around ±2.5 D of best-focus PSF (BF-PSF) using double-pass PSF system. Modulation transfer function (MTF) area of the BF-PSF was calculated from BF-PSF to represent the peripheral optical quality. Relative peripheral defocus (RPD), the refraction of anterior/posterior focal lines, MTF area, and their correlations with myopia progression were analyzed.

Results

The average refractive change in 9 months was ?0.5?±?0.8 D. The change in axial length was significantly positively correlated with the amount of myopic progression (P?=?0.0058) and RPD (P?=?0.0007, 0.0036 and 0.0040, at 10°, 20°, 30° respectively) at the initial visit, but did not correlate with the peripheral MTF area. Myopic progression of more than 0.5 D with axial elongation was observed in seven children (MP group). The RPDs at 20° and 30° in the MP group were significantly more hyperopic than in the non-MP group (P?=?0.002 and 0.007), whereas there was no significant difference in axial length, and central and peripheral MTF area between the MP and non-MP groups. MP group had more hyperopic focal lines compared with non-MP group at 20°and 30°.

Conclusion

These results suggest that the progression of axial myopia in children is associated with hyperopic RPD and refraction of focal lines, not with peripheral optical quality.     

儿童近视进展的机制及其干预

近年来,针对近视发生和发展的可能机制,学者们从遗传、调节滞后、远视性离焦等多个方面进行了大量的动物研究和临床试验.目前延缓近视发展的主要措施有渐进多焦点眼镜、双光眼镜、角膜塑形镜等.此外,学者们在阿托品等药物防控近视方面也进行了有益的探索.     

阿托品联合双焦镜控制青少年轻中度近视疗效分析

Objective To evaluate the efficacy and safety of topical atropine and bifocal lens in slowing the progression of myopia and ocular axial elongation in children with slight to moderate myopia. Methods This trial included 62 children with slight to moderate myopia. They were all being treated in the Second Hospital of the Zhengzhou of Henan. Forty-two children were treated with 1% atropine ointment once daily before sleep for 1 year, and were demanded to wear bifocal lens at the same time. The other children were assigned to control group. Baseline and last assessments of refractive errors by cycloplegic autorefiaction and of axial length were done by ultrasound biometry. Intraocular pressure and corneal curvature were also recorded. The results were compared with data of control subjects. Results The visual acuity of 38 eyes (36.84%) in the treated group cutted down, compared with 80% in the control group. After 1 year, the mean progression of myopia and of axial elongation in the control group was -1.19±1.48D and 0.70± 0.63mm respectively. In the atropine-treated eyes, the mean progression of myopia was only±0.06± 0.79D and of axial elongation was 0.09± 0.19mm. Five children were forced to stop treatment because of photophobia and anaphylactic conjunctivitis. No other major adverse effects related to the treatment were noted. Conclusions 1% Atropine ointment and bifocal lens are safe and effective treatment for retarding myopic progression in slight to moderate myopia.This treatment is well tolerated by most children.     

阿托品联合双焦镜控制青少年轻中度近视疗效分析

Objective To evaluate the efficacy and safety of topical atropine and bifocal lens in slowing the progression of myopia and ocular axial elongation in children with slight to moderate myopia. Methods This trial included 62 children with slight to moderate myopia. They were all being treated in the Second Hospital of the Zhengzhou of Henan. Forty-two children were treated with 1% atropine ointment once daily before sleep for 1 year, and were demanded to wear bifocal lens at the same time. The other children were assigned to control group. Baseline and last assessments of refractive errors by cycloplegic autorefiaction and of axial length were done by ultrasound biometry. Intraocular pressure and corneal curvature were also recorded. The results were compared with data of control subjects. Results The visual acuity of 38 eyes (36.84%) in the treated group cutted down, compared with 80% in the control group. After 1 year, the mean progression of myopia and of axial elongation in the control group was -1.19±1.48D and 0.70± 0.63mm respectively. In the atropine-treated eyes, the mean progression of myopia was only±0.06± 0.79D and of axial elongation was 0.09± 0.19mm. Five children were forced to stop treatment because of photophobia and anaphylactic conjunctivitis. No other major adverse effects related to the treatment were noted. Conclusions 1% Atropine ointment and bifocal lens are safe and effective treatment for retarding myopic progression in slight to moderate myopia.This treatment is well tolerated by most children.     

阿托品联合双焦镜控制青少年轻中度近视疗效分析

目的 探讨长期滴用1%阿托品凝胶并联合应用双焦镜对治疗青少年轻中度近视的有效性及安全性.方法 选取2008年1月至2009年3月于眼科门诊就诊的62例轻中度近视患者,将其按2:1比例随机分为治疗组42例和对照组20例.治疗组给予1%阿托品凝胶每晚睡前一次滴眼,连续使用一年,同时联合应用双焦镜;对照组则根据视力和症状给予常规验光配镜,局部及全身均不使用任何药物.所有患者在受试前均接受全面的眼科检查作为基线标准,一年试验结束后检查视力、屈光度(散瞳验光)、眼轴、眼压及角膜曲率,将两组结果进行对比分析.结果 治疗组视力下降率为36.84%,而对照组为80%,明显高于治疗组.治疗起始时治疗组的屈光度(SEQ)为(-2.18±1.05)D,对照组为(-2.12±1.33)D,1 年后治疗组的屈光度平均改变(+0.06±0.79)D,而对照组为(-1.19±1.48)D,对照组屈光度下降程度明显高于治疗组,两组比较有显著性差异.治疗组1年后眼轴平均增长(0.09±0.19)mm,对照组眼轴增长(0.70±0.63)mm,治疗组眼轴较起始无明显改变而对照组明显增长.所有观察对象均未出现眼压升高.两组间角膜曲率在治疗前及治疗后均无明显差异.对照组无人中途退出,治疗组42例中有5例(11.9%)因畏光及过敏性结膜炎而退出试验.结论 阿托品联合双焦镜能够有效控制并延缓近视发展,长期使用1年未发现明显的不良反应,患者能够耐受该治疗.     

Meridional corneal components of myopia progression in young adults and children

Records were selected from a data pool of myopic private practice patients to study the relation of refractive error change and keratometer power change in young adulthood. Selection was on the basis of three or more refractions and keratometer readings at and/or after 18 years of age. There were significant correlations between rate of myopia progression and rate of keratometer power change. Linear regression slopes of rate of refractive error change on rate of keratometer power change were in the neighborhood of 0.7. These findings were in contrast to the lack of correlation between myopia increase and corneal steepening in childhood myopia progression. Young adulthood myopia progression also appeared to be accompanied by a slight tendency toward a with-the-rule astigmatic shift.     

角膜塑形术对少儿近视进展的影响

目的　观察角膜塑形术治疗少儿近视眼的远期疗效 ,探讨其对近视眼的影响。方法　用睫状肌麻痹检影的方法 ,检查 1 0 0只少儿中低度近视眼角膜塑形术治疗 3年前后的屈光度变化 ,与同年龄对照组近视眼的进展情况进行比较。进行等效检验统计分析。结果　角膜塑形术治疗终止后平均屈光度比 3年前增加 1 3 8± 0 2 7D ,对照组 3年内共增加 1 48± 0 2 9D。两均数经统计检验等效。结论　角膜塑形术对少儿近视进展影响不明显。