To investigate glaucoma progression based on Optical Coherence Tomography (OCT) Guided Progression Analysis (GPA) according to baseline β-zone parapapillary atrophy (PPA) morphology in glaucoma patients.

Retrospective cohort study.

Patients over 20 years of age who had been diagnosed with primary open-angle glaucoma (POAG) at Seoul National University Hospital, Seoul, Korea between 2010 and 2020. This study included POAG patients with a minimum of 5 years of follow-up. We quantitatively measured the baseline β-zone PPA parameters, classified β-zone PPA morphology according to new classification standard we created and analyzed the corresponding GPA progression of the retinal nerve fiber layer (RNFL).

A total of 210 patients with POAG (mean age: 53.8 years) were enrolled in the study. The mean follow-up period was 9.8 years. The average value of the baseline mean deviation in visual field perimetry was -2.48 dB. Longer radial extent and larger angular extent of β-zone PPA were significantly associated with progression on GPA, as was the presence of disk hemorrhage. Among the 4 classified β-zone PPA morphologies (Crescent type 1 & 2, Solar-eclipse type 1 & 2), the Solar-eclipse type 2 group showed the highest progression. A Kaplan-Meier survival analysis demonstrated significant differences among the 4 types.

The larger the radial and angular extents of β-zone PPA, the more progression that was shown on OCT GPA. Furthermore, significant differences in progression were noted based on the morphological type of β-zone PPA. Our findings indicate that baseline β-zone PPA parameters and morphology are valuable predictors of future glaucoma progression.