Novel anterior-chamber angle measurements by high-definition optical coherence tomography using the Schwalbe line as the landmark
Carol Y Cheung, Ce Zheng, Ching-Lin Ho, Tin A Tun, Rajesh S Kumar, Fouad El Sayyad, Tien Y Wong, Tin Aung
British Journal of Ophthalmology | B M J PUBLISHING GROUP | Published : 2011
OBJECTIVE: To propose the Schwalbe line (SL) as a new anatomical landmark, independent of the scleral spur (SS) location, for assessing anterior chamber angle (ACA) width quantitatively with high-definition optical coherence tomography (HD-OCT). METHODS: Study subjects underwent dark-room gonioscopy and HD-OCT in one randomly selected eye. The authors developed a computer-aided program to define two new quantitative parameters for assessing ACA width: Schwalbe line-angle opening distance (SL-AOD) measured at the SL, and Schwalbe line-trabecular-iris space area (SL-TISA) measured 500 μm from the SL. The associations between SL parameters, SS parameters and gonioscopic grading were evaluated. ..View full abstract
Grants from the National Medical Research Council and the National Research Foundation, Singapore.TYW and TA have received grant funding from Carl Zeiss Meditec, but this was not related to the subject of this study. TA has received travel support and honoraria from Carl Zeiss Meditec.