Relationship between vessel density and visual field sensitivity in glaucomatous eyes with high myopia

Aims To investigate the global and regional relationships between peripapillary vessel density (pVD) and visual field mean sensitivity (VFMS) in glaucomatous eyes with and without high myopia in comparison with those between peripapillary retinal nerve fibre layer thickness (pRNFLT) and VFMS. Methods A total of 130 eyes from 130 patients with glaucoma consisting of those with and without high myopia were included in a consecutive manner. High myopia was defined as a spherical equivalent <-6.0 dioptres or axial length > 26.5 mm. The pVD and pRNFLT were evaluated using optical coherence tomography angiography (OCT-A) and spectral-domain optical coherence tomography. VFMS was assessed using a linear unlogged 1/L scale. The vasculature-function or structure-function relationships were analysed by comparing the pVD or pRNFLT to the corresponding VFMS, according to Garway-Heath map regionalisation. Results The global pVD-VFMS association was significantly stronger than the pRNFLT-VFMS association in glaucomatous eyes with high myopia (p=0.009). However, there were no significant differences between global pVD-VFMS and pRNFLT-VFMS associations in glaucomatous eyes without high myopia (p=0.343). Regionally, the pVD-VFMS association was significantly greater than the pRNFLT-VFMS association at the superonasal, nasal and temporal sectors (all p< 0.05) in glaucomatous eyes with high myopia. Conclusions The pVD assessment by OCT-A shows a better global and regional correlation with VFMS than a pRNFLT assessment in glaucoma patients with high myopia. The pVD may be a useful parameter in monitoring disease progression of highly myopic glaucomatous eyes.