To measure angle of anterior chamber using Topcon SD-OCT: A new technique

Abstract

The proposed new method of measuring angle of anterior chamber is an effective method of measuring the angles. Identification of narrow anterior chamber angle is important for glaucoma screening and prophylactic treatment prevents acute angle closure glaucoma event.Aim of this study wasto measure the angle of anterior chamber using Topcon spectral domain optical coherence tomography (SD OCT).In this cross-sectional study 120 normal subjects above the age of 40 years were enrolled. The study was done at the tertiary health care center of central Indian. All volunteers had visual acuity of at least 6/9 with no ocular diseases. Using OCT the angle opening distance (AOD-500), trabecular–iris angle (TIA) and trabecular-iris space area (TISA-500) were measured. In this study the mean AOD was 0.430 µm in nasal and 0.433 µm in temporal quadrant. The mean TISA in nasal was 0.405 µm and temporal quadrant was 0.408 µm. While the mean trabecular iris angle (TIA) was 26.9° in nasal and 26.01° in temporal quadrant. The study proved that the proposed method of measuring AOD, TISA, TIA is the effective method as the Topcon-2000 OCT does not have any inbuilt software like that of other ASOCT machines.