GlaucoRAG: A Retrieval-Augmented Large Language Model for Expert-Level Glaucoma Assessment

PurposePurpose: Accurate glaucoma assessment is challenging because of the complexity and chronic nature of the disease; therefore, there is a critical need for models that provide evidence-based, accurate assessment. The purpose of this study was to evaluate the capabilities of a glaucoma specialized Retrieval-Augmented Generation (RAG) framework (GlaucoRAG) that leverages a large language model (LLM) for diagnosing glaucoma and answering to glaucoma specific questions. DesignEvaluation of diagnostic capabilities and knowledge of emerging technologies in glaucoma assessment. ParticipantsDetailed case reports from 11 patients and 250 multiple choice questions from the Basic and Clinical Science Course (BCSC) Self-Assessment were used to test the LLM based GlaucoRAG. No human participants were involved. MethodsWe developed GlaucoRAG, a RAG framework leveraging GPT-4.5-PREVIEW integrated with the R2R platform for automated question answering in glaucoma. We created a glaucoma knowledge base comprising more than 1,800 peer-reviewed glaucoma articles, 15 guidelines and three glaucoma textbooks. The diagnostic performance was tested on case reports and multiple-choice questions. Model outputs were compared with the independent answers of three glaucoma specialists, DeepSeek-R1, and GPT-4.5-PREVIEW (without RAG). Quantitative performance was further assessed with the RAG Assessment (RAGAS) framework, reporting faithfulness, context precision, context recall, and answer relevancy. Main Outcome MeasuresThe primary outcome measure was GlaucoRAGs diagnostic accuracy on patient case reports and percentage of correct responses to the BCSC Self-Assessment glaucoma items, compared with the performance of glaucoma specialists and two benchmark LLMs. Secondary outcomes included RAGAS sub scores. ResultsGlaucoRAG achieved an accuracy of 81.8% on glaucoma case reports, compared with 72.7% for GPT-4.5-PREVIEW and 63.7% for DeepSeek-R1. On glaucoma BCSC Self-Assessment questions, GlaucoRAG achieved 91.2% accuracy (228 / 250), whereas GPT-4.5-PREVIEW and DeepSeek-R1 attained 84.4% (211 / 250) and 76.0% (190 / 250), respectively. The RAGAS evaluation returned an answer relevancy of 91%, with 80% context recall, 70% faithfulness, and 59% context precision. ConclusionsThe glaucoma-specialized LLM, GlaucoRAG, showed encouraging performance in glaucoma assessment and may complement glaucoma research and clinical practice as well as question answering with glaucoma patients.