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

PURPOSE: To propose a comprehensive, evidence-based classification system for open-angle glaucoma (OAG) that integrates risk profiling, modern optic nerve functional and structural diagnostic testing and analytics, and disease velocity. METHODS: We synthesized data from landmark randomized clinical trials and utility analysis studies. Critical gaps in current systems were identified, specifically regarding the 'pre-perimetric' 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 seven 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 (e.g., OHTS 5-year risk less than 5% rather than arbitrary IOP cutoffs), whereas Stage 2 (Glaucoma Suspect) requires at least one major risk factor or at least two minor risk factors. Stage 3 (Mild Glaucoma) reflects the presence of GON detected by optical coherence tomography (OCT) prior to visual field loss. Stage 4 (Moderate Glaucoma) denotes the presence of peripheral visual field damage limited to one visual hemifield. Stage 5 (Severe Glaucoma) utilizes central 5-degree involvement and/or widespread disease to reflect Quality of Life impact. 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. CONCLUSION: 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 OCT-defined glaucomatous optic neuropathy and a modifier for active progression, this framework is intended to align disease classification with contemporary diagnostics and longitudinal risk assessment.