Topographic analysis of choroidal thickness in pachychoroid disease using ultra-widefield swept-source optical coherence tomography

PURPOSE: To characterise regional and topographic choroidal thickness (CT) profiles using ultra-widefield swept-source optical coherence tomography (UWF SS-OCT) and to compare topographic CT between normal eyes and eyes with pachychoroid disease. METHODS: All participants underwent UWF SS-OCT using an approximately 26 mm × 21 mm field of view with fixation centred on the fovea. CT was quantified within concentric rings centred on the optic nerve head and stratified by sector. Linear mixed-effects models were performed separately for each sector, adjusting for age, sex and spherical equivalent (SE). Main outcome measures were regional CT differences between normal and pachychoroid eyes. RESULTS: 60 subjects were included in the study. 37 participants (61.7%) were males and 23 (38.3%) were females. 24 participants (40%) were classified as pachychoroid and 36 (60.0%) as normal. Across all sectors and eccentricities, pachychoroid eyes demonstrated significantly greater CT compared with normal eyes (p