Discriminant Function of Optical Coherence Tomography Angiography to Determine Disease Severity in Glaucoma.

PURPOSE

To determine the discriminant function of optical coherence tomography angiography (OCTA) by disease severity in glaucoma.

METHODS

In this prospective, observational cross-sectional study, all subjects underwent visual fields, retinal nerve fiber layer (RNFL) measurements, and OCTA imaging. Local fractal analysis was applied to OCTA images (radial peripapillary capillaries [RPC] layer). Vessel density en face and inside the disc and spacing between large and small vessels were quantified. Stepwise logistic regression was performed and a glaucoma severity score (range, 0-1: 0, normal; 1, severe glaucoma) was developed by using global and regional (superotemporal [ST], inferotemporal [IT], temporal, superonasal [SN], inferonasal, and nasal) vascular parameters. Glaucoma severity score was compared with visual field and RNFL indices.

RESULTS

One hundred ninety-nine eyes (112 subjects) with glaucoma (28 eyes preperimetric; 83 early, 43 moderate, and 45 severe glaucoma) and 74 normal (54 subjects) eyes were enrolled. Preperimetric and glaucomatous eyes had significantly altered (P 0.05) to visual fields for perimetric glaucoma. Glaucoma severity score identified preperimetric glaucoma and early glaucoma better than did visual fields.

CONCLUSIONS

Vascular parameters could be a useful adjunct tool to evaluate/diagnose glaucoma. Longitudinal studies are needed to determine their use in early detection and prognostication.