Iluminar o Glaucoma: Ligação entre as Respostas Pupilares e Alterações Funcionais e Estruturais na Hipertensão Ocular e no Glaucoma Primário de Ângulo Aberto

INTRODUCTION: This study assessed the relationship between the pupillary light reflex and both functional and structural loss in patients with ocular hypertension (OHT) and primary open-angle glaucoma (POAG), using automated pupillometry, a precise method for measuring pupillary responses. By examining this relationship, the study seeks to provide insights into how changes in pupillary function correspond to glaucoma development, potentially improving diagnostic and monitoring methods. METHODS: A cross-sectional study enrolling OHT and POAG patients across the whole spectrum of disease severity was conducted. Monocular dynamic pupillary responses were recorded using an automatic quantitative pupillometry system. The relative amplitude of pupil constriction was calculated as the percentage change in pupil diameter from onset to peak constriction. All patients underwent standard automated perimetry and optical coherence tomography within one year before pupillometry, and the relationship between pupillary responses and these parameters was analyzed. RESULTS: The study included 136 eyes from 68 subjects (mean age 68.6±10.268.6±10.2 years, 52.9% female). Significant correlations were found between all monocular pupillary light response parameters and structural and/or functional measurements, except for initial pupil diameter. When controlling for confounders (age and sex), the relative amplitude of pupil constriction remained significantly correlated with campimetric parameters - mean deviation (r=0.274,p=0.003r=0.274,p=0.003), pattern standard deviation (r=0.261,p=0.005r=0.261,p=0.005), and visual field index (r=0.281,p=0.002r=0.281,p=0.002). Retinal nerve fiber layer (r=0.271,p=0.003r=0.271,p=0.003) and retinal ganglion cell complex (r=0.208,p=0.025r=0.208,p=0.025) thickness were also significantly positively associated. Significant correlations were found between disease groups, particularly between the OHT group and early-stage POAG, for the relative amplitude (p=0.011p=0.011) and velocity (p=0.003p=0.003) of pupil constriction. CONCLUSION: In glaucomatous eyes, reduced pupillary light responses were linked to more advanced visual field loss and structural retinal damage. These findings highlight automated pupillometry’s potential as a precise, non-invasive tool for detecting functional and structural impairments. Its ability to discern OHT from early-stage POAG further underscores its diagnostic value, allowing earlier intervention in at-risk patients. As the technology evolves, its increased accessibility could benefit both specialized clinics and community settings, enabling earlier diagnosis and better patient care.