Vitelliform lesions and choroidal changes in chorioretinal disorders: pathophysiological insights and clinical implications

: This narrative review aims to explore the correlation between choroidal thickness (CT), broader choroidal changes, and the development and progression of vitelliform lesions, with a focus on their potential modulatory role-whether primary or secondary- through mechanisms involving choriocapillaris (CC) and retinal pigment epithelium (RPE) dysfunction. CT was found to be significantly increased in various vitelliform maculopathies, including adult-onset foveomacular vitelliform dystrophy (AOFVD), Best disease, autosomal recessive bestrophinopathy, age-related macular degeneration (AMD), and pachychoroid disease spectrum (PDS) disorders. Notably, increased subfoveal CT was associated with the presence and progression of subretinal hyperreflective material and subretinal fluid in AOFVD and Best disease. In PDS disorders, choroidal thickening, pachyvessels, and choroidal vascular hyperpermeability were identified as key contributors to RPE dysfunction and vitelliform lesion formation. Conversely, leptovitelliform maculopathy was characterised by thinner choroid in association with reticular pseudodrusen or subretinal drusenoid deposits. An important feature is CC dysfunction, which is often associated with pachyvessels, even in the absence of a clear pachychoroid-related phenotype or choroidal thickening. These findings underscore the importance of CT evaluation in clinical practice and highlight the need for further research to elucidate the complex relationship between CT and vitelliform maculopathies.