Description of cohort

The design, inclusion and exclusion criteria and the participants in the natural history of the progression of choroideremia (NIGHT) study have already been described in detail.⁷

Briefly summarised for the purpose of this article, subjects with a confirmed genetic diagnosis of choroideremia were enrolled in this multicentre study. All participants underwent spectral domain optical coherence tomography (SDOCT) and FAF imaging at baseline using the Heidelberg Spectralis HRA+OCT (Heidelberg Engineering, Heidelberg, Germany) system. OCT imaging was performed using 30×25 degree field of view and a 5.9 mm×5.9 mm pattern size with an ART of 12 images averaged. FAF images were obtained using 488 nm (‘blue peak’) light and a 30 degree field of view, centred on the fovea. The analyses in this study were approved by the Institutional Review Board of the University of California, Los Angeles. The research adhered to the tenets set forth in the Declaration of Helsinki.