Abstract
Purpose :
Decreased choroidal flow has been observed in eyes with retinal vasculopathy using optical coherence tomography angiography (OCTA). However, there is limited information regarding reliability of quantifying choroidal vascular flow in these eyes using OCTA. This study aims to evaluate the repeatability of macular choroidal vascular flow measurements using a commercial OCTA instrument and the effect of retinal vasculopathy and macular edema.
Methods :
This is a prospective cross-sectional study of 29 patients (52 eyes). All eyes were imaged twice, 30 minutes apart, using an Optovue AngioVue OCTA instrument to obtain 3 x 3 mm scans of the macula centered on the fovea. Choroidal flow was quantified using ImageJ. Repeatability of choroidal flow measurement was calculated using the intraclass correlation coefficient (ICC) as follows: poor if < 0.5, moderate if 0.5-0.75, good if 0.75-0.90 and excellent if > 0.9.
Results :
Among 52 eyes, mean BCVA was 20/30 (range 20/20 to 20/200). Among 28 eyes with retinal vasculopathy, 20 had diabetic retinopathy, 8 had retinal vein occlusion, and 25 eyes had concurrent macular edema. Eyes without retinal vasculopathy or macular edema includes 16 eyes with disc edema from optic neuropathy and 8 normal eyes. Mean signal strength of the OCTA scans was 7 (range 2 to 9). Mean choroidal vascular flow was significantly lower in eyes with retinal vasculopathy compared to eyes without (57.1% v 54.9%, p = 0.006). Macular choroidal vascular flow measurements of all eyes demonstrated excellent repeatability (ICC = 0.900 [95% CI, 0.827-0.942]). ICC of eyes with retinal vasculopathy was similar to eyes without retinal vasculopathy (ICC = 0.884 [95% CI, 0.735-0.948] vs ICC 0.904 [95% CI, 0.792-0.955], respectively). Presence of macular edema had minimal effect repeatability (ICC = 0.858 [95% CI, 0.654-0.939]).
Conclusions :
Macular choroidal flow measurements using a commercial OCTA instrument had good repeatability which was not significantly reduced in eyes with retinal vascular pathology and/or macular edema. Our findings support the use of OCTA to quantify macular choroidal flow in eyes with retinal vascular disease.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.