A Unified, Progression-Integrated, Structural Model for Classification of Open-Angle Glaucoma and Individuals at Risk

PURPOSE: To propose a comprehensive, evidence-based classification system for open-angle glaucoma that integrates risk profiling, modern optic nerve functional and structural diagnostic testing and analytics, and disease progression rate. METHODS: We synthesized data from landmark randomized clinical trials and utility analysis studies. Critical gaps in current systems were identified, specifically regarding the "preperimetric" window and macular vulnerability. A new staging framework was developed to align disease definitions with biological severity, rates of progression, and therapeutic urgency. RESULTS: The proposed system stratifies the glaucoma continuum into the following 7 stages. Stages 0, 1, and 2 are assigned using a formalized risk-factor framework in eyes without glaucomatous optic neuropathy (GON). Stage 0 (healthy) denotes individuals with no identifiable risk factors for glaucoma. Stage 1 (at risk) corresponds to a single minor risk factor with otherwise low calculated risk (eg, Ocular Hypertension Treatment Study 5-year risk <5% rather than arbitrary intraocular pressure cutoffs), whereas stage 2 (glaucoma suspect) requires at least 1 major risk factor or at least 2 minor risk factors. Stage 3 (mild glaucoma) reflects the presence of GON detected by optical coherence tomography before visual field loss occurs. Stage 4 (moderate glaucoma) denotes the presence of peripheral visual field damage limited to 1 visual hemifield. Stage 5 (severe glaucoma) uses central 5° involvement and/or widespread disease to reflect the impact on quality of life. Stage 6 (end-stage glaucoma) reflects significant glaucoma-related visual disability. A novel "(+) disease" modifier, analogous to retinopathy of prematurity staging systems, is introduced to denote clinically significant active progression, signaling the need for more intensive surveillance or treatment. CONCLUSIONS: We propose a comprehensive staging framework for open-angle glaucoma that integrates structural imaging, functional testing, and progression risk into a unified classification system. By incorporating optical coherence tomography-defined GON and a modifier for active progression, this framework is intended to align disease classification with contemporary diagnostics and longitudinal risk assessments.