Abstract
Purpose :
It has been shown that opacity of optical media can reduce retinal vessel density (VD) measured by some models of optical coherence tomography angiography (OCTA). However, different models of OCTA used different algorithms and may have different effect. This study is aimed to investigate the impact of optical media opacities on quantitative measurement of Cirrus 5000 and DRI Triton OCTA.
Methods :
Cirrus 5000 and DRI Triton OCTA were used to image retinal microvasculature from 22 right eyes at the macula using 3mm×3mm scanning protocol. The VD of superficial capillary plexus was measured using the built-in software. Optical opacities were simulated with neutral-density filters (optical density (OD)λ=840nm ranges 0.10 - 0.48 in Cirrus; ODλ=1050nm ranges 0.15 - 0.51 in DRI) placed in front of each eye, signal strength (SS) or signal strength intensity (SSI), and parafoveal VD were then recorded and measured. The correlation between the parameters and OD was analyzed.
Results :
With the increase of OD, SS and SSI decreased (rs= -0.576 and -0.922 respectively, both p＜0.001), parafoveal VD decreased in Cirrus 5000 (rs= -0.539, p＜0.001). Parafoveal VD increased as SS increased in Cirrus 5000 (rs= 0.471, p＜0.001). There was no correlation between parafoveal VD and OD or SSI in DRI Triton (rs= -0.143, p= 0.137 and rs= -0.009, p= 0.924 respectively).
Conclusions :
The effect of optical media opacity on quantitative measurement of VD is different for Cirrus 5000 and DRI Triton OCTA.
This is a 2020 ARVO Annual Meeting abstract.