Structural Changes Due to MS in Retinal, Choroidal Vasculature Found

This study demonstrated that both central and peripheral retinal vascular alterations, as along with choroidal changes, are present in MS and occur largely independent of prior optic neuritis. These OCT-A images from the study show (A) foveal cross-section and segmented blood flow (yellow), (B) en face image of the superficial vascular complex and (C) an ETDRS grid depicting concentric rings used for microcapillary density measurements. Photo: Mitchell J, et al. Ophthalmol Sci. April 15, 2026. Click image to enlarge. Beyond the hallmark demyelinating lesions characteristic of multiple sclerosis (MS), a growing body of evidence highlights a range of vascular abnormalities within the brain. Functional abnormalities in the retina, such as increased arteriolar oxygenation and impaired vascular reactivity, have been observed and appear to parallel cerebral vascular dysfunction. However, structural changes in the retinal and choroidal vasculature remain poorly characterized. Researchers based in Belfast in the UK recently determined that structural retinal and choroidal vascular alterations in MS were associated with disability and disease progression, independent of prior optic neuritis.The Belfast Eye and MS study (BEAMS) is a prospective, observational, cross-sectional, case-control study to assess the feasibility and utility of multimodal retinal imaging in MS. The study cohort consisted of 16 participants with MS and 25 controls. Of the 32 eyes of individuals with MS, 21 (65.6%) had no history of optic neuritis, while 11 (34.4%) had experienced a past event of optic neuritis. Multimodal retinal imaging that was performed included color fundus photography, ultra-widefield imaging, optical coherence tomography (OCT) and OCT angiography (OCT-A). Retinal vascular parameters and choroidal vascular parameters were compared between control eyes and eyes with and without optic neuritis using regression models. Associations of these vascular parameters with Expanded Disability Status Scale (EDSS) scores and annual EDSS progression rate were assessed.Compared to controls, eyes with MS but without optic neuritis showed narrower central retinal venules, an increased arteriole-to-venule ratio and a reduced venular fractal dimension. Disability correlated with increased venular caliber, vessel density, superficial vascular complex capillary density and choroidal thickness and decreased arteriole-venule ratio and choroidal vascularity index.Annual EDSS progression was associated with increased arteriolar caliber, arteriolar-to-venular ratio, superficial complex density capillary density, foveal avascular zone (FAZ) volume and deep FAZ area and a decreased venular width gradient and fractal dimension. Eyes with MS and optic neuritis showed narrower venular caliber, density and fractal dimension. When these eyes were compared, optic neuritis affected only central arteriolar caliber and global superficial vascular complex capillary density.Although eyes with MS and without optic neuritis generally exhibited narrower venules and a less complex venular network compared to controls, higher disability scores and faster annual disability progression were associated with wider venular caliber within the MS group.“This apparent paradox—narrowing at the group level yet dilation with increasing disability within MS—may reflect distinct pathophysiological processes operating at different disease stages or severity strata,” the researchers noted in their paper, which was published in Ophthalmology Science. “This association remained significant after adjusting for age, sex, spherical error and hypertension.” “This exploratory study provides evidence that MS is associated with structural alterations in both the retinal and choroidal vasculature, involving not only the microcapillary network but also arterioles, venules and the peripheral retinal vascular tree, even in eyes without prior optic neuritis,” the study concluded. “These changes may reflect impaired neurovascular coupling and/or blood-retina barrier dysfunction, potentially secondary to neurodegeneration, or conversely, driven by hypoperfusion and hypoxia as initiating events.”The research team noted that their findings were limited by the cross-sectional design and modest sample size, which preclude causal inference and limit statistical power for subgroup analyses. Future studies should adopt longitudinal designs with larger, well-characterized cohorts and integrate structural and functional measures, such as oxygenation and vascular reactivity, alongside radiological and inflammatory markers, and possibly account for the influence of different disease-modifying therapies.Click here for the journal source. Mitchell J, McIlwaine G, Pead E, et al. Central and peripheral alterations of retinal and choroidal vasculature in multiple sclerosis: insights from multimodal imaging. Ophthalmol Sci. April 15, 2026. [Epub ahead of print]. This article was developed by the editorial staff in conjunction with experts in the field. In the process, AI may have been among the editorial tools used to meet the goals of human editors, who approved all content.