Abstract
Purpose :
Optical coherence tomography angiography (OCTA) and laser speckle contrast imaging (LSCI) are two technologies for non-invasively quantifying retinal blood flow, which is reportedly reduced in glaucoma. However, comparative studies on the static and dynamic measures of blood flow, as provided by these two imaging modalities, are limited. We investigated the relationship between OCTA and LSCI measurements of the peripapillary retinal vasculature in glaucoma, glaucoma suspect, and healthy eyes.
Methods :
We prospectively enrolled 3 glaucoma, 3 glaucoma suspects, and 6 healthy subjects. For OCTA, the Heidelberg Spectralis OCT2 was used to measure peripapillary perfusion density (PD). For LSCI, the XyCAM Retinal Imager was used to measure systolic (peak), diastolic (trough), and mean blood flow velocity indices (BFVi – arbitrary units) in the vessels within the optic disc while masking the optic disc interstitium. Mann–Whitney U test was used to compare pairs of independent groups. Spearman correlation was used to evaluate the relationships between OCTA and LSCI measurements.
Results :
OCTA PD correlated significantly and equally with systolic (r = 0.51; p < 0.04) and mean BFVi (r = 0.51; p < 0.04). OCTA PD did not significantly correlate with diastolic BFVi (r = 0.35; p = 0.14).
Conclusions :
We provide a quantitative comparison between static measurements of peripapillary blood flow by OCTA and dynamic measurements by LSCI. Our results are comparable or better than previously reported associations between these two technologies (Kiyota et al. 2018). Notably, OCTA correlated more with LSCI during systole as compared to diastole. These findings suggest that the pulsatile behavior of blood flow in systole and diastole as measured by dynamic imaging modalities may be clinically useful for evaluating ocular disease such as glaucoma.
This is a 2020 ARVO Annual Meeting abstract.