Abstract
Purpose: :
To report normative results of corneal and anterior segment biometric parameters and their associations in Malay adults, for use in preoperative assessment for corneal and anterior segment surgery.
Methods: :
The Singapore Malay Eye Study (SiMES) is a cross-sectional, population-based study of urban Malays aged 40 to 80 years. The subjects underwent ophthalmic and systemic examination that included imaging with anterior segment optical coherence tomography (AS-OCT). Ocular parameters were subsequently measured with the Zhongshan Assessment Program (ZAP): Anterior chamber depth (ACD), central corneal thickness (CCT), anterior and posterior corneal curvature (ACC and PCC), as well as posterior corneal arc length (PCAL), which is a novel parameter defined as the arc distance between scleral spurs on the posterior border of the cornea. Age- and sex-adjusted analyses and multivariate analyses were performed to determine correlations of PCAL with other ocular biometric, systemic and refractive components.
Results: :
We studied 237 subjects of which the mean age was 56.6 ± 10.4 years and 50.2% were women. Ocular parameters (mean ± SD) included central ACD 2.78 ± 0.34 mm, CCT 550.23 ± 37.12 mm, ACC 7.43 ± 0.37mm, PCC 6.75 ± 0.37mm and PCAL 13.95 ± 0.51mm. There was significant correlation observed between PCAL and ACD (r=0.476, p<0.001), PCC (r=0.243, p<0.001) and ACC (r=0.251, p<0.001), but poor correlation between PCAL and age, BMI, blood pressure, blood glucose levels, HbA1c and refractive parameters. Multivariate analysis showed a significant association between PCAL and ACD (p<0.001), PCC (p<0.001), age (p<0.05), female sex (p<0.05) and height (p<0.05).
Conclusions: :
This study provides the largest baseline normative data of corneal and anterior segment dimensions in an adult Asian Malay population. In this study, PCAL was found to correlate moderately with ACD. These data are clinically applicable for assessment and surgical management of patients requiring anterior segment or corneal surgery.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • anterior segment • imaging/image analysis: clinical