HIGH PREVALENCE OF MYOPIA IN JAPANESE PATIENTS WITH IDIOPATHIC FOCAL SUBRETINAL NEOVASCULARIZATION

Genetic factors for idiopathic choroidal neovascularization

Objective: The aim of this study was to investigate genetic factors associated with idiopathic choroidal neovascularization (ICNV). Methods: We conducted a case-control study including 69 cases with ICNV and 114 controls who underwent cataract surgery. Single nucleotide polymorphisms (SNPs) from genes reported to be related to AMD, CNV and uveitis were selected for this study. Results: In an univariate analysis, the rs669676 SNP located in the COL8A1 gene was associated with the proportion of people who has idiopathic CNV ( X2 = 9.3453, corrected p-value = 0.1). For the rs669676 SNP, minor allele homozygotes, in the dominant model of genotype analysis (GG versus AA-GA), it showed significant differences in the ICNV group vs controls (p = .01, OR = 1.219 (95%CI: 1.04-1.429)). Conclusions: The rs669676 SNP located in the COL8A1 gene may contribute to a genetic susceptibility for ICNV.

Design, methodology, and baseline data of the Personalized Addition Lenses Clinical Trial (PACT)

BACKGROUND

The aim of this study was to describe the design, methods, and baseline characteristics of children enrolled in the Personalized Addition lenses Clinical Trial (PACT). PACT aims to test the myopia control efficacy of progressive addition lenses (PALs) with personalized addition values compared with standard (+2.00 D) addition PALs and single vision lenses (SVLs).

METHODS

PACT is a randomized, controlled, double-masked clinical trial. Two hundred eleven myopic Chinese children (7-12 years) were enrolled and randomized into 1 of the 3 following groups: personalized addition PALs; +2.00 addition PALs; and SVLs. Personalized addition values were determined based on the highest addition that satisfied Sheard criterion. Axial length and other biometric data were also recorded.

RESULTS

At baseline, no differences were found between the right and left eyes for any of the main parameters. The enrolled children were 9.7 ± 1.1 years' old with cycloplegic autorefraction (right eye [OD]: -2.36 ± 0.64 D), near phoria (1.0 ± 5.0 prism diopter esophoria), lag of accommodation (1.40 ± 0.50 D) and axial length (OD: 24.58 ± 0.74 mm). The personalized addition values ranged from +0.75 to +3.00 (average ± SD: 2.19 ± 0.73 D).

CONCLUSION

PACT is a clinical trial evaluating whether myopia progression in children can be slowed by wearing personalized addition PALs compared with fixed addition PALs and SVLs as measured by cycloplegic autorefraction and axial length. Baseline data were comparable with those of previous myopia control studies in children. Subjects will be followed up every 6 months for 2 years.

Epidemiology of myopia

Myopia is one of the most prevalent disorders of the eye. Higher myopia is associated with comorbidities that increase risks of severe and irreversible loss of vision, such as retinal detachment, subretinal neovascularization, dense cataract, and glaucoma. In recent years, reports from population-based prevalence studies carried out in various geographical areas now give a clear picture of the current distribution of refractive error. The scarcity of data from well-designed longitudinal cohort studies is still yet to be addressed. These studies have confirmed the previous data indicating that prevalence of refractive error varies according to ethnicity and geographic regions, and also point to an increase in myopia prevalence over the past half-century. The problem is particularly pronounced in affluent, industrialised areas of East Asia. Environmental risk factors for myopia related to socioeconomic status and lifestyle have been identified. The past decade has seen a greater understanding of the molecular biological mechanisms that determine refractive error, giving further support to the belief that myopia is the result of a complex interaction between genetic predisposition and environmental exposures. This review summarizes data on the prevalence, incidence, progression, associations, risk factors, and impact from recent epidemiological studies on myopia.

Risk factor analysis of 167 patients with high myopia

AIM

To analyze the risk factors of age, sex, course, best corrected visual acuity (BCVA), diopter and fundus features of high myopes with progressive high myopia.

METHODS

A total of 167 patients with high myopes were categorized into four groups: group 1, age 10-29 years; group 2, age 30-49 years; group 3, age 50-69 years and group 4, age 70-89 years. The refractive errors of all patients were measured without cycloplegia with an autorefractometer. Data of the spherical equivalent (SE) of the refractive errors in diopters (D) and fundus examined by direct ophthalmoscope were used in statistical analysis.

RESULTS

The number of female was statistically larger than that of male (P<0.01), also the disease course was correlated to the age. The visual acuity of high myopes significantly decreased as they grew older including the higher incidence of lacquer cracker, submacular hemorrhage, Fuchs spots, chorioretinal atrophy.

CONCLUSION

Female maybe a risk factor of high myopia, advanced age is an important factor of visual acuity decreased. High myopes ought to be treated early to delay the progress of myopia and development of macular degeneration.