The eye as a window to the brain: Neuroretinal thickness is associated with microstructural white matter injury in HIV-infected children

Abstract

PURPOSE. Despite combination antiretroviral therapy (cART), perinatal HIV-infection can cause decreased gray and white matter volume, microstructural white matter injury, and retinal structural abnormalities. As neuroretinal tissue is directly connected to the brain, these deficits may have a shared pathogenesis. We aimed to assess associations between neuroretinal thickness and cerebral injury in cART-treated perinatally HIV-infected children and healthy controls. METHODS. This cross-sectional observational study included 29 cART-treated perinatally HIVinfected children and 35 matched healthy controls. All participants underwent 3.0 Tesla magnetic resonance imaging (MRI), determining gray and white matter volumes from T1weighted sequences, and white matter diffusivity using diffusion tensor imaging (DTI). Regional individual and total neuroretinal layer thickness was quantified using spectraldomain optical coherence tomography. We explored associations between retinal and cerebral parameters using multivariable linear regression analysis. RESULTS. In HIV-infected children, lower foveal and pericentral neuroretinal thickness was associated with damaged white matter microstructure, in terms of lower fractional anisotropy and higher mean and radial diffusivity. In healthy controls only, neuroretinal thickness was associated with gray and white matter volume. CONCLUSIONS. Decreased neuroretinal thickness is associated with microstructural white matter injury, but not with lower cerebral volume in HIV-infected children. This suggests that HIV-induced retinal thinning and microstructural white matter injury may share a common pathogenesis, and longitudinal assessment of neuroretinal alterations in parallel with MRI and neuroinflammatory markers may further our insight into the pathogenesis of HIV-induced cerebral injury in children.