Comparison of vascular-function and structure-function correlations in glaucomatous eyes with high myopia.

BACKGROUND/AIMS: To determine the usefulness of peripapillary retinal vessel density (VD) measured using optical coherence tomography (OCT) angiography (OCTA) in the evaluation of glaucomatous visual field damage in highly myopic eyes with primary open-angle glaucoma (POAG).
METHODS: This cross-sectional observational study enrolled a total of 124 myopic POAG eyes consisting of 40 eyes showing a segmentation error (SE) in OCT scans and 84 eyes without an SE. The peripapillary retinal VD, circumpapillary retinal nerve fibre layer thickness (RNFLT) and visual field sensitivity loss (VFSL) were assessed using OCTA, spectral-domain OCT and standard automated perimetry, respectively. The topographical correlations between the VD and VFSL, and between the RNFLT and VFSL were determined in subgroups divided according to the presence of an SE.
RESULTS: The peripapillary retinal VD showed significant topographical correlation with VFSL both in the highly myopic POAG eyes without an SE globally (R=0.527, p<0.001), and in temporal (R=0.593), temporal-superior (R=0.543), nasal-inferior (R=0.422) and temporal-inferior sectors (R=0.600, all p<0.001), and in those with an SE globally (R=0.343, p=0.030), and in temporal (R=0.494, p=0.001), temporal-superior (R=0.598, p<0.001), and temporal-inferior sectors (R=0.424, p=0.006). The correlation with VFSL did not differ between the VD and RNFLT in the eyes without an SE
CONCLUSION: Peripapillary VD as measured with OCTA showed a topographical correlation with VFSL in highly myopic POAG eyes regardless of the presence of an OCT SE OCTA may be a useful adjunct for evaluating glaucomatous visual field damage in high myopia, where the OCT results are frequently confounding. © Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.