Anterior Chamber Depth in Elderly Chinese: The Liwan Eye Study
Received 13 August 2007; received in revised form 1 December 2007; accepted 4 December 2007. published online 09 May 2008.
Purpose
To assess the anterior chamber depth (ACD) and its variation with age, gender, and angle width in elderly Chinese in an urban area of southern China.
Design
Cross-sectional study.
Participants
Adults 50 and older were identified using cluster random sampling in Liwan District, Guangzhou.
Methods
Gonioscopy was performed before ACD measurements to estimate the geometric angle width according to the Shaffer system. ACD was measured using optical pachymetry. True ACD was calculated by subtracting central corneal thickness from the distance between the anterior corneal epithelium and the anterior lens capsule. Data were presented for the right phakic eyes.
Main Outcome Measures
Anterior chamber depth and gonioscopy.
Results
Among 1405 participants in the study, data from 1248 right eyes were available for analysis. The mean ACD values for men and women were 2.59 mm (95% confidence interval [CI], 2.56–2.62; 25th–75th percentile, 2.37–2.82) and 2.42 mm (95% CI, 2.39–2.44; 25th–75th percentile, 2.21–2.63). Mean ACD declined by 0.09 mm (95% CI, −0.011 to −0.008) per decade (adjusted for gender) and was 0.18 mm (95% CI, −0.213 to −0.141) shallower in women than men (adjusted for age). The ACD was found to be monotonically associated with gonioscopic angle width, decreasing from 2.73 mm (standard deviation [SD], 0.26) in Shaffer grade 4 to 1.94 mm (SD, 0.27) in Shaffer grade 0. There was also a relationship between ACD and refractive error; mean spherical equivalent decreased by 0.030 mm ACD per diopter.
Conclusions
This study confirms an inverse association between ACD and age, female gender, and spherical refractive error. Eyes with shallower ACDs had narrower angles.
Available online: May 9, 2008.
1State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China.
2University College London Institute of Ophthalmology, London, United Kingdom.
3Department of Ophthalmology, Hillerød Hospital, Hillerød, Denmark.
4Glaucoma Research Unit, Moorfields Eye Hospital, London, United Kingdom.
Correspondence to Mingguang He, MD, PhD, Department of Preventive Ophthalmology, Zhongshan Ophthalmic Center, Guangzhou 510060, China.
Manuscript no. 2007-1067.
Dr He is recipient of a University College London (London, United Kingdom) Graduate School Research Scholarship and Overseas Research Scholarship (no. 2001061054) and grants from Scientific and Technology Foundation of Guangdong Province, Guangzhou, China (no. 2005B30901008), and Sun Yat-sen University Clinical Research 5010 Project, Guangzhou, China. Dr Foster receives support from the Medical Research Council, London, United Kingdom (grant no. G0401527); Wellcome Trust, London, United Kingdom (grant no. 075110); and Richard Desmond Charitable Foundation, London, United Kingdom (via Fight for Sight).
No author has any financial or intellectual conflicts of interest in the material presented.
ABSTRACT