Long-Term Clinical Course and Progression Patterns of Normal-Tension Glaucoma Following Disc Hemorrhage.

Purpose: The purpose of this study was to determine the long-term clinical course and patterns of progressive retinal nerve fiber layer (RNFL) thinning and their associated factors in eyes with normal-tension glaucoma (NTG) following disc hemorrhage (DH). Methods: This longitudinal case series included 227 eyes with NTG followed for ≥10 years after experiencing at least one DH episode. Rates and patterns of global RNFL thinning were assessed using linear and nonlinear regression models. Risk factors for faster RNFL loss and distinct progression patterns were evaluated using random-forest modeling with SHapley Additive exPlanations (SHAP) analysis. Results: Most eyes (93.8%, n = 213) exhibited significant RNFL thinning during follow-up, with 33.0% (n = 75) demonstrating nonlinear progression patterns. The average rate of thinning did not adequately reflect the complexity of progression in eyes with nonlinear progression patterns. Random-forest modeling identified that the key predictors of rapid RNFL thinning were a larger number of additional IOP-lowering medications after first detecting DH, less-severe visual field (VF) damage, and a smaller %IOP reduction. The presence of a decelerating progression pattern (P_dec) was associated with a thicker lamina cribrosa, a larger %IOP reduction, a larger number of additional medications after first detecting DH, and younger age. Subgroup analyses of P_dec eyes showed that earlier stabilization was associated with lower initial IOP, fewer episodes of DH recurrence, and less-severe VF damage. Conclusions: RNFL thinning after DH occurred in diverse patterns, with a substantial proportion of eyes demonstrating late-phase stabilization. Clinical features indicative of smaller mechanical stress were likely key factors in attenuating glaucoma progression following DH.