Quantitative Comparison of Swept-Source and Spectral-Domain OCT Angiography in Healthy Eyes

Abstract

Background and objective: To compare macular vessel density (VD) and foveal avascular zone (FAZ) area in healthy individuals using two different optical coherence tomography angiography (OCTA) devices.

Patients and methods: In this prospective, comparative study, 25 eyes of 14 healthy subjects underwent fovea-centered 3 mm × 3 mm OCTA-imaging using the Triton (Topcon, Tokyo, Japan) and RS-3000 (Nidek, Gamagori, Japan) OCTA devices. Superficial and deep retinal layers (SRL/DRL) and FAZ were manually graded after threshold standardization to determine macular VD and area of the FAZ.

Results: The mean difference in the VD between the two devices was 0.105 and 0.096, and the coefficient of variation (CV) was 19.59% and 16.90% for the SRL and DRL, respectively. After skeletonization of vessels to remove variation related to vessel width, the mean difference was 0.174 mm^-1 and 0.516 mm^-1, and the CV was 3.49% and 1.07% for SRL and DRL, respectively. The mean difference of FAZ area was 0.001 mm² and 0.010 mm² in the SRL and DRL, respectively, and the CV was 2.17% and 5.74% for the SRL and DRL, respectively.

Conclusion: Macular VD using skeletonized mapping and FAZ area in SRL and DRL were statistically similar between the two devices, demonstrating a possible comparison of quantitative values between different OCTA devices. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:385-391.].