Choriocapillaris and choroidal thickness in all Leber hereditary optic neuropathy stages using swept source technology

Purpose: The role of the choroid in Leber hereditary optic neuropathy (LHON) remains unclear. The literature is scarce, with conflicting results and lacks axial length measurements. Therefore, we aimed to analyse the choriocapillaris (CC) vessel density (VD) and choroidal thickness (ChT) in all stages of LHON using swept source (SS) technology and considering the possible influence of axial length on choroidal parameters.Methods: This was a prospective cross-sectional observational study. A total of 119 eyes of 60 patients with molecularly confirmed LHON across all stages and 120 eyes of 60 control participants were included. We obtained the CC VD using optical coherence tomography angiography maps centred on the fovea. ChT was measured from the Bruch's membrane to the choroid-sclera interface in the macular and peripapillary regions.Results: The CC VD was not significantly affected in any sector or average, except for a slight change in the superior region of chronic eyes (52.08 +/- 1.62% vs. 53.50 +/- 2.29%, p = 0.002). ChT demonstrated a trend towards decreased values in asymptomatic eyes and increased values in the symptomatic stages that failed to reach statistical significance in sectors corresponding to the papillomacular bundle except for the macular nasal inner sector of chronic eyes (281.10 +/- 67.12 mu m vs. 252.08 +/- 70.55 mu m, p = 0.045). No significant correlations were observed between visual acuity and CC VD or ChT.Conclusion: The CC VD remained stable across the LHON stages. Choroidal vasculature does not appear to play a role in LHON pathophysiology. Further research is needed on ChT as a potential biomarker of LHON.