Fractal dimension of the retinal vasculature and risk of stroke: A nested case-control study

Abstract

Recent studies show associations between retinal vascular changes and small infarcts detected on brain imaging, or clinical stroke.1 Fractal dimension has been used as a global measure of the geometric pattern of the retinal vasculature2,3 potentially representing the complex branching pattern of the microvasculature, including the cerebral microvasculature. We have developed an automatic method to assess spectrum fractal dimension (SFD) of the retinal microvasculature using Fourier-transformed images.4,5 Two previous studies have reported cross-sectional associations between retinal fractal dimension and lacunar stroke.6,7 In this study, we aimed to examine the association between baseline SFD and stroke incidence using a case-control sample nested in the Blue Mountains Eye Study (BMES). ### Methods. The BMES is a population-based cohort study of an urban population aged 49 years or older (n = 3,654), representing 82.4% of eligible population in a defined area of the Blue Mountains region, Australia.1 Stroke cases were defined among participants with no past history of stroke at baseline (1992–1994) but who developed stroke during the subsequent 5 years (1997–1999), or who died from stroke or stroke-related causes by late 2005. Detailed definitions of stroke events and mortality are shown in …