Optical coherence tomography-derived biomarkers for disease severity in choroideremia and choroideremia carriers

This study aimed to evaluate the association between optical coherence tomography (OCT)-derived biomarkers and disease severity in patients with choroideremia (CHM) and CHM carriers.

We retrospectively reviewed consecutive CHM patients and female carriers who underwent comprehensive ophthalmic imaging. Evaluated OCT biomarkers included central macular thickness (CMT), cystoid space (CS), outer retinal tubulation (ORT), and hyperreflective foci (HF). Disease severity in CHM patients was assessed using the preserved islet area (PIA) on fundus autofluorescence images, while a pre-existing grading system was applied for carriers. Linear mixed models were used to assess the associations.

Thirty-one affected males (62 eyes) and nine female carriers (18 eyes) were included. In CHM patients, the total number of HF showed a significant negative correlation with PIA (β = -0.449, 95% CI: -0.853 to -0.045; p = 0.043). Subgroup analysis revealed that choroidal HF in the fovea was significantly associated with reduced PIA (β = -0.221, 95% CI: -0.379 to -0.063; p = 0.015). Other OCT biomarkers, including CMT, CS, and ORT, were not significantly correlated with disease severity. In female carriers, none of the OCT biomarkers differed significantly across the stages of fundus severity.

The total number of HF and choroidal HF in the fovea showed significant associations with disease severity measures in CHM, suggesting potential utility as structural biomarkers alongside established OCT parameters. No OCT-derived biomarkers were significantly associated with disease severity among the CHM carriers.