Correlates Between Humphrey Field Analyzer and Vessel Density in the Superior and Inferior Retinal Hemispheres of Glaucoma Suspects

Abstract

Purpose : The purpose of this study was to investigate the relationship between Humphrey Field Analyzer (HFA) global indices and vessel density (VD) as measured by OCTA in the superior and inferior hemi-retinas in glaucoma suspects.

Methods : 15 subjects (29 eyes) were enrolled in the cross-sectional study conducted at the Manhattan Eye Ear and Throat Hospital from a longitudinal study on glaucoma suspects. Subjects with suspicious optic nerve head morphology underwent a comprehensive ophthalmologic examination, HFA, optical coherence tomography angiography (OCTA), and PERG. OCTA macular 3x3 scans were processed using ImageJ (vessel analysis plugin). The Foveolar Avascular Zone (FAZ) was manually measured, and VD was calculated for superior and inferior macula (rectangular ROI), superior and inferior parafoveal areas (1 mm radius circle from macular center) with FAZ, superior and inferior parafoveal areas without FAZ. Partial correlation analysis controlling for age and hypertension were calculated for the VD variables against average retinal nerve fiber layer (RNFL) thickness, HFA Visual Field Indices MD, PSD, and VFI for test grids 24-2 and 10-2.

Results : The mean age was 57.93 ± 12.74 years with 27.6% males. The average RFNL thickness was 90.82 ± 9.58 μm, the average intraocular pressure was 17.34 ± 3.19 mmHg, and 24.1% had arterial hypertension. Partial correlation analysis showed significant associations between HFA PSD 10-2 and VD of both the inferior parafoveal area including the FAZ (p = 0.027, r = -0.424) and the inferior parafoveal area not including the FAZ (p = 0.033, r = -0.412). No other significant relationships were found.

Conclusions : We report a significant relationship between VD in the inferior parafoveal area and HFA PSD 10-2, regardless of whether the FAZ is included in the VD analysis or not. This underlines the vascular predisposition of the lower retinal hemisphere to glaucoma and predicts future visual defects. Decreases in lower retinal hemisphere VD may be a risk factor for scotoma in the superior hemifield. Further investigation of the vascular basis of glaucoma is warranted.

This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.