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Effective management of ocular hypertension requires precise risk stratification to prevent conversion to glaucoma. While the landmark Ocular Hypertension Treatment Study (OHTS) identified key risk factors, its reliance on subjective optic disc grading introduced significant inter-observer variability. Artificial intelligence (AI), especially the “Machine-to-Machine" (M2M) deep learning models”, now enables the mapping of features from one modality to another. The AI-driven prediction of retinal nerve fiber layer (RNFL) thickness from optic disc photographs may help to determine risk for development of primary open-angle glaucoma (POAG) in patients with ocular hypertension. In this diagnostic study by Liu et al., researchers applied an M2M deep learning model, trained with 32,820 pairs of fundus photographs and the associated OCT scans, to 64,755 optic disc photographs from 1,444 participants in the OHTS cohort. The model successfully stratified risk, showing that baseline predicted RNFL was significantly thinner in converters (94.1 µm) compared to non-converters (97.1 µm), with a hazard ratio (HR) of 1.83 per 10-µm thinning. Notably, the longitudinal rate of change proved even more predictive: converters demonstrated an RNFL thinning rate nearly double that of non-converters (-0.42 µm/year vs -0.25 µm/year). A 1-µm/year faster loss was associated with a 6-fold increase in conversion risk. This study effectively validates M2M-derived RNFL as a potent biomarker for risk stratification. However, several technical and clinical nuances warrant future refinement. First, because this is a secondary analysis of the historical OHTS dataset, lacking prospective clinical validation, these predicted RNFL lack validation against ground-truth OCT measurements. Second, the model's mean absolute error of 7.4 μm deriving slopes from these estimated values risks amplifying measurement noise1, which may fail to accurately reflect the true slope. Finally, the reliance on serial fundus photography to calculate slopes limits its utility in opportunistic screening, where clinicians prioritize immediate prediction at the first encounter over long-term monitoring2-3. Future research should aim to overcome these barriers by integrating AI-generated structural metric with raw imaging features or functional modalities. Such multimodal integration could mitigate estimation noise and transform the current risk model into a precise, personalized prediction engine for individual patient care.