Abstract
Purpose :
The aim of this study is to evaluate the relationship between Bruch’s membrane opening (BMO) of the optic nerve head (ONH) and the degree of visual field (VF) severity in patients with open angle glaucoma.
Methods :
Thirty right eyes of 30 patients with open-angle glaucoma (OAG) and 30 right eyes of 30 healthy controls were included. All patients underwent spectral-domain optical coherence tomography (SD-OCT) and Standard Automated Perimetry (SAP) VF testing. Twenty-four radial scans of the optic nerve head and 1 circular scan of the peripapillary retina were obtained with the SD-OCT; BMO-based ONH parameters were determined. The angle between the fovea and BMO center (FoBMO), relative to the horizontal axis of the image frame was first determined, and all scans were acquired and analyzed in relation to this eye-specific parameter. Minimum rim width (MRW), retinal nerve fiber layer thickness (RNFLT), perpendicular rim width (PRW), horizontal rim width (HRW), as well as the minimum rim area (MRA) within the neuroretinal tissue defined by the MRW, and the perpendicular rim area (PRA) within the neuroretinal tissue defined by the PRW, were obtained and analyzed with respect to age, sector and BMO shape. The obtained parameters were also correlated with the Mean Deviation (MD), Pattern Standard Deviation (PSD), and the Visual Field Index (VFI) of the VF through Spearman’s correlation method.
Results :
Mean patient age in the OAG group was 61.4 ±14.7 years, 60% (n=18) of patients were female. The mean FoBMO angle was −5.8° (range: 2.9° to −18.3°), significant correlations were found between MD, PSD and BMO parameters, with PRW and PRA showing the highest values (0.9646, P < 0.001) in the OAG group. This group also showed high correlation in the temporal–inferior sector in the sectorial analysis (0.8757, P < 0.001); the age association showed to be stronger with BMO-MRW than with RNFLT (P < 0.01); there was a modest relationship between mean global BMO-MRW and RNFLT ( P < 0.02).
Conclusions :
The BMO-based ONH parameters present a strong correlation with the VF severity in patients with open angle glaucoma. This method allows to carry out a precise and objective evaluation of the anatomy of the ONH, that could represent an accurate diagnostic tool for OAG with a good structure-function relationship.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.