Comparison of a commercial spectral-domain OCT and swept-source OCT based on an angiography scan for measuring circumpapillary retinal nerve fibre layer thickness. Issue 7 (4th October 2019)

• Record Type: Journal Article
• Authors: Tan, Bingyao; Chua, Jacqueline; Harish, Thiyagrajan; Lau, Amanda; Gan, Alfred Tau Liang; Tan, Yar Li; Wong, Damon W K; Chong, Rachel Shujuan; Ang, Marcus; Husain, Rahat; Schmetterer, Leopold
• Is Part Of: British journal of ophthalmology. Volume 104:Issue 7(2020)
• Page Start: 974
• Page End: 979
• Publication Date: 2019-10-04
• Subjects: retina -- imaging; Ophthalmology -- Periodicals; 617.7
• DOI: 10.1136/bjophthalmol-2019-314706
• Languages: English
• ISSNs: 0007-1161

Abstract

Abstract : Background/aims: To assess the agreement in measuring retinal nerve fibre layer (RNFL) thickness between spectral-domain (SD; Cirrus HD, Carl Zeiss Meditec, USA) optical coherence tomography (OCT) and swept-source (SS; Plex Elite 9000, Carl Zeiss Meditec) OCT using an OCT angiography (OCTA) scanning protocol. Methods: 57 participants (12 glaucomatous, 8 ocular hypertensive and 74 normal eyes) were scanned with two OCT instruments by a single experienced operator on the same day. Circumpapillary RNFL thicknesses were automatically segmented for SD-OCT and manually segmented for SS-OCTA scans. Agreement of global RNFL thickness, as well as average thickness in four quadrants was assessed using intraclass correlation coefficients (ICCs). Results: There was excellent agreement in the inferior and superior quadrants and the global (all ICC >0.90), followed by good agreement in the temporal (ICC=0.79) and nasal (ICC=0.73) quadrants. The ICC values were similar in the subgroups except within the ocular hypertension group, where the nasal quadrant was less agreeable (ICC=0.31). SS-OCTA-derived RNFL thickness was on average 3 µm thicker than SD-OCT, particularly in the nasal (69.7±11.5 µm vs 66.3±9.3 µm; p<0.001) and temporal (75.6±13.7 µm vs 67.9±12.3 µm; p<0.001) quadrants. Conclusions: RNFL measurements taken with SS-OCTA have good-to-excellent agreement with SD-OCT, which suggests that the RNFL thickness can be sufficiently extracted from wide-field OCTA scans.