Measurement of Macular Choroidal Thickness in Narrow Angle Patients by Optical Coherence Tomography

Background: Primary angle-closure glaucoma (PACG) carries a greater risk of causing significant visual impairment compared to primary open-angle glaucoma (POAG). Changes in choroidal thickness (CT) have been implicated in its pathogenesis. Optical coherence tomography (OCT) provides a non-invasive method to evaluate macular choroidal thickness (MCT), which may enhance early detection and risk stratification in patients with narrow-angle conditions. This study aims to investigate and compare MCT in individuals with narrow-angle conditions using OCT. Methods: This case-control study included 75 participants, categorized into three equal groups: Group I (patients with angle-closure glaucoma), Group II (angle-closure suspects), and Group III (healthy controls). CT was assessed in sub-foveal, nasal, and temporal regions utilizing OCT. Results: Sub-foveal, nasal, and temporal choroidal thicknesses were considerably greater in Groups I and II compared to Group III (p < 0.001), with no notable differences observed between Groups I and II. Sub-foveal CT demonstrated a positive correlation with intraocular pressure (IOP) (r = 0.475, p = 0.017) and a negative correlation with spherical equivalent (SE) (r = -0.428, p = 0.033). Temporal CT showed a significant positive correlation with age (r = 0.603, p = 0.001) and best-corrected visual acuity (BCVA) (r = 0.444, p = 0.026). Conclusion: Increased MCT, particularly in sub-foveal, nasal, and temporal regions, may serve as an indicator for angle-closure risk, correlating with elevated IOP and refractive measures. OCT imaging could thus be valuable in early diagnosis and monitoring of angle-closure conditions.