Study finds visual function and retinal features in female carriers of choroideremia

Female carriers of choroideremia (CHM) exhibit varying degrees of visual impairment and retinal structural changes, which can be effectively assessed using multimodal imaging and microperimetry techniques, according to a study.

Key findings from the study, which included 43 CHM carriers and 30 healthy age-matched controls, found that CHM carriers, predominantly confirmed through genetic testing (86%), exhibited distinct retinal phenotypes compared to controls. The study identified significant correlations between eyes in CHM carriers for parameters such as best-corrected visual acuity and average retinal sensitivity (P < 0.001). Tests measuring low-luminance visual acuity and volumetric analysis of the macular hill of vision were particularly sensitive in detecting subtle changes associated with milder retinal phenotypes among CHM carriers.

Choroideremia carriers with severe phenotypes, such as geographic or male pattern retinal changes, demonstrated marked reductions in BCVA, low-luminance visual acuity, retinal sensitivity, and exhibited retinal thinning. Despite generalized photoreceptor complex thinning across the central 7 degrees of the retina, inner retinal thickening was observed in the central 1 degree, suggesting a complex pattern of retinal remodeling in CHM carriers.

The study did not establish clear genotype-phenotype correlations but underscored the utility of low-luminance visual acuity and macular hill of vision volumetric measures in assessing disease progression among CHM carriers.

Reference
Gocuk SA, Edwards TL, Jolly JK, et al. Retinal characteristics of female choroideremia carriers: Multimodal imaging, microperimetry and genetics. Ophthalmol Retina. 2024;S2468-6530(24)00304-X. doi: 10.1016/j.oret.2024.06.011. Epub ahead of print. PMID: 38936773.