Determinants of anterior chamber depth in a large Caucasian population and agreement between intra-ocular lens Master and Pentacam measurements of this variable

Abstract

Purpose: To establish the main determinants of anterior chamber depth (ACD) in Caucasian subjects and examine agreement between IOL Master(®) (Carl Zeiss, Meditec) and Pentacam(®) (Oculus Inc.) ACD measurements.

Methods: In a cross-sectional study, 1006 right eyes of 1006 healthy subjects were subjected to a general ophthalmologic examination using the Pentacam(®) , IOLMaster(®) and OCT RTVue(®) (Optovue Inc.). The variables recorded were age, sex, intra-ocular pressure, spherical refractive error, axial length (AL), central corneal thickness, corneal diameter, iris thickness, and anterior chamber depth, volume and angle (ACA). The effects of these variables on ACD were analysed by multivariate linear regression.

Results: Mean age was 49.1 years (range 18-84); 61% were women. In 98.3% of the eyes, ACD could be measured using the IOL Master and in 98% the Pentacam was used to give mean depths of 3.30 ± 0.42 mm and 3.35 ± 0.43 mm, respectively, for the two instruments. Agreement between these devices was high. In men, ACD was 0.13 mm on average deeper than in women (p < 0.001). ACD was correlated with ACA, AL, corneal diameter, spherical refractive error and age (p < 0.001). Five variables - age, sex, spherical error, corneal diameter and ACA - were able to explain 74.1% of the variation produced in ACD (R(2) = 0.741; p < 0.001), among which age emerged as the main determinant (partial R(2) = 0.279; p < 0.001).

Conclusions: Age, sex, spherical error, corneal diameter and ACA correlate highly with ACD and together serve to explain much of its variation. When used to measure ACD, the IOLMaster and Pentacam show excellent agreement.

Keywords: ageing; anterior chamber depth; intra-ocular lens master; pentacam.