Anterior segment imaging: Fourier‐domain optical coherence tomography versus time‐domain optical coherence tomography

PURPOSE: To compare anterior segment measurements and morphology of 2 optical coherence tomography (OCT) systems. SETTING: Department of Ophthalmology, District Railway Hospital, and the Nursing Department and Social Medical Issues, Health Care Division, Silesian Medical University, Katowice, Poland. METHODS: In normal eyes and in eyes with corneal and trabecular–iris angle disorders, the central corneal thickness (CCT), trabecular–iris angle, and angle‐opening distance at the nasal and temporal angles were measured 3 times during 1 visit using the Visante time‐domain OCT system and the RTVue‐100 Fourier‐domain corneal anterior module OCT system. Anterior segment morphology was assessed and compared. RESULTS: Fifty‐four eyes were evaluated. The mean values (±SD) by time‐domain OCT and Fourier‐domain OCT were, respectively, automatic CCT, 535 ± 33.07 μm and 538 ± 31.82 μm; manual CCT, 545 ± 30.91 μm and 542 ± 30.57 μm; nasal trabecular–iris angle, 34.7 ± 9.5 degrees and 35.2 ± 8.9 degrees; temporal trabecular–iris angle, 35.3 ± 8.5 degrees and 35.5 ± 9 degrees; nasal angle‐opening distance, 435 ± 95 μm and 444 ± 98 μm; and temporal angle‐opening distance, 443 ± 103 μm and 452 ± 99 μm. There was no significant difference between mean values, and they were highly correlated. On morphologic analysis, time‐domain OCT had lower resolution; however, all anterior chamber structures were visible on 1 image. Fourier‐domain OCT provided precise information about small areas of the anterior chamber. CONCLUSION: Fourier‐domain OCT provided accurate anterior eye segment measurements that agreed with those obtained with time‐domain OCT.