Biometric relationships of ocular components in esotropic amblyopia

Abstract

Purpose: To investigate the contribution of the individual ocular components, i.e. anterior chamber depth, lens thickness and vitreous chamber depth, to total axial length in patients with esotropic amblyopia. Methods: The study population consisted of 74 children, aged between 5 and 8 years: thirty-seven patients with esotropic amblyopia and 37 healthy volunteers (control group). The participants underwent a comprehensive ophthalmological examina tion, including cycloplegic refraction and A-scan ultrasonography. Anterior chamber depth, lens thickness, vitreous chamber depth and total axial length were recorded. Paired Student's t-tests were used to compare biometric measurements between amblyopic eyes and their fellow eyes and between right and left eyes in the control group. To evaluate the contribution of the ocular components to the total axial length, we report the individual components as a percentage of total axial length. Results:The comparison between amblyopic and fellow eyes regarding the individual contribution from ocular components to the total axial length revealed greater contribution from lens thickness (P=0.001) and smaller contribution from vitreous chamber depth (P=0.001) in amblyopic eyes, despite similar contribution from anterior chamber depth (P=0.434). The comparison between right and left eyes in the control group showed similar contributions from anterior chamber depth (P=0.620), lens thickness (P=0.721), and vitreous chamber depth (P=0.483). Conclusions: This study shows differences between amblyopic and non-amblyopic eyes when the total axial length is broken down into the individual contribution from the ocular components.

Ocular Biometric Characteristics of Chinese with History of Acute Angle Closure

“…Formulas were used to assess the risk of angle closure such as anterior segment length (ASL: summation of CCT, ACD, and LT) [ 19 ], the contribution of individual ocular components to the total axial (ACD/AL, LT/AL, VCD vitreous chamber depth/AL) [ 41 ], and the relative lens position (RLP: calculated as (ACD + 1/2LT)/AL) [ 42 ].…”

“…Firstly, because all patients were of Han Chinese descent and were recruited from the Department of Ophthalmology, Zhongshan Hospital, the results of this study may not be applicable to other racial groups and may not be generalizable to the larger population. Secondly, some studies have shown that cortical or nuclear cataracts may also be associated with angle closure [ 41 ]. However, the presence of severe cataracts makes measurements of LT and AL difficult, so such patients were excluded.…”