Abstract
Purpose :
Primary angle closure glaucoma (PACG) is a leading cause of irreversible blindness. Although longitudinal changes in static and dynamic anterior segment structure with age was important for predicting future risk of PACG, data on this topic is limited. Our hypothesis is that static and dynamic parameters of the anterior segment would change over time.
Methods :
A population-based, cohort study was conducted among subjects aged 50 and older residing in Liwan District, Guangzhou, China. In November 2008 and November in 2013, a systematically selected subjects underwent complete ocular examinations and anterior segment optical coherence tomography (AS-OCT) imaging under dark and light conditions. Customized Zhongshan Angle Assessment Program (ZAAP) software was used to AS-OCT parameters.Baseline and 5-year change in AS-OCT parameters in dark and light-to-dark changes were determined.
Results :
A total of 160 (66.4%) subjects underwent AS-OCT examinations in 2008 and 2013 were eligible for analyses. The mean age of analysed subjects was 64.8 ±7.1 years, and 65.6% were female. Overall, there was an trend of narrowing of angle in dark, with decreasing significantly in angle parameters (AOD500, TISA500) , anterior chamber parameter (ACD, ACW, ACA, ACV), increases in iris parameters (IT750, IT2000, Iarea, Icurve, Ivolume), and LV at 5 years (all P<0.05). Similar trend of parameter of light-to-dark changes were observed. After adjusting age and sex, the following baseline parameters were associated with a greater decrease in TISA500 at 5 years: height, AOD250, TISA500, TISA750, ARA, ΔAOD500, ΔTISA500, ΔTISA750, ΔARA, ΔACW, and ΔACA (all P<0.05).
Conclusions :
Angle width decreased, iris and lens vault increased, and light-to-dark changes declined during the 5-year follow-up. Subjects with greater baseline height, wider angle width, more pronounced dark-to-light changes experienced greater angle narrowing at follow-up.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.