Original articleDeterminants of Angle Width in Chinese Singaporeans
Section snippets
Materials and Methods
Approval for the study was granted by the Singapore Eye Research Institute institutional review board. This study was conducted in accordance with the Declaration of Helsinki, and written informed consent was obtained from all subjects before enrollment.
The primary population consists of subjects recruited from an ongoing population-based cross-sectional study of Chinese persons aged ≥40 years (the Singapore Chinese Eye Study). The study methodology and details of the study population have been
Statistical Analysis
For the primary population, linear regression modeling using the R2 best subsets selection method was performed with TISA750 and AOD750 as the dependent angle width variables. This method finds subsets of independent variables that best predict a dependent variable by linear regression and display the models in decreasing order of R2 magnitude within each subset size. R2 is a descriptive measure between 0 and 1 indicating how well one term predicts another, with perfect prediction when R2=1.
Results
For the primary population-based study, complete data for analysis were available for 1547 subjects. Among them, 480 subjects were excluded from analysis for the following reasons: a history of intraocular surgery in 29, indeterminate sclera spurs in 279, poor-quality ASOCT images in 70, and Zhongshan Angle Assessment Program software delineation errors in 102. Final analysis was thus performed on 1067 subjects. The mean age of the subjects was 56.9±8.5 years, and 49.8% were female. There was
Discussion
The current analysis supports defining angle closure as a multifactorial condition that can be caused by either one or a combination of variations in size, shape, and position of anterior segment structures. By incorporating all the established and newly identified anatomic factors for angle closure,1, 2, 3, 4, 11, 12, 13, 14 we found that ACA, ACV, and LV were the 3 most important determinants of angle width, the pathogenic site of PACG. A predictive model comprising 6 quantitative ASOCT
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2020, American Journal of OphthalmologyCitation Excerpt :These findings support mathematical models that predict a significant increase in IC secondary to pupillary block, which plays a key role in the pathogenesis of primary angle closure.28 The results of our univariate analyses are consistent with results from the population-based study of Chinese Singaporeans by Foo and associates.21 Ignoring anterior chamber area and anterior chamber volume, which were omitted from our study for the aforementioned reasons, the R2 values for the 4 strongest determinants of AOD750 were LV (0.56), ACD (0.46), IC (0.48) and AL (0.30).
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Manuscript no. 2011-384.
Financial Disclosure(s): The author(s) have made the following disclosure(s): Dr. T. Aung has received research funding, travel support, and honoraria from Carl Zeiss Meditec. Dr. Wong has received research funding from Carl Zeiss Meditec. Dr. Friedman has received an instrument loan from Carl Zeiss Meditec.
Funding: Grants from the National Medical Research Council, Singapore, and the National Research Foundation, Singapore.