Prediction of Glaucoma Progression with Structural Parameters: Comparison of Optical Coherence Tomography and Clinical Disc Parameters

Abstract

To test the hypothesis that baseline optical coherence tomography (OCT) measures predict visual field (VF) progression in a cohort of patients with suspected or established glaucoma and to compare their performance to semiquantitative optic disc measures. This was an observational cohort study. The setting of this study was an academic institution. The study population included 171 eyes of 95 patients with good-quality baseline retinal nerve fiber layer (RNFL) and macular OCT images and disc photographs with >2 years of follow-up and ≥5 VFs. The observation procedures were baseline macular and RNFL OCT measures and cup-to-disc ratio and disc damage likelihood score. The main outcome measure was prediction of glaucomatous VF deterioration according to trend and event analyses. Median (interquartile range) baseline mean deviation and follow-up were -2.9 (-6.4 to -1.1) dB and 54 (44-65) months, respectively. Seventeen and 25 eyes progressed by final visit based on pointwise event analysis and trend analysis of visual field index (VFI), respectively. Thinner central corneal thickness (P=.005), female gender (P= .015), and thinner average peripapillary RNFL (P= .001) predicted VF progression on proportional hazard models. Thinner RNFL at baseline (P= .006) or thinner average ganglion cell-inner plexiform layer (P= .028) along with higher baseline VFI (P= .018 and .048, respectively) predicted VFI progression. Neither optic disc measures predicted VF progression in any of the explored models. Baseline structural OCT measures predicted subsequent VF progression in contrast to semi-quantitative optic disc measures. OCT-based structural measures should be included in prognostic models of glaucomatous VF deterioration.