Cerebral magnetic resonance imaging (MRI) scans often reveal sulcal widening and ventricular enlargement in elderly people. These imaging characteristics are believed to reflect atrophy of the brain, as part of the spectrum of cerebral changes associated with aging. However, sulcal widening and ventricular enlargement have also been independently linked with cardiovascular risk factors such as hypertension, diabetes, and cigarette smoking and with a prior history of stroke, suggesting that vascular mechanisms may also contribute to the pathogenesis of these cerebral characteristics. Because the retinal vessels are accessible to direct noninvasive evaluation and share common anatomic, embryologic, and physiologic characteristics with the cerebral microcirculation, these vessels offer a unique opportunity to investigate the role of the microcirculation in cerebrovascular diseases. Abnormalities of the retinal arterioles (for example, microaneurysms, retinal hemorrhages, and arteriolar narrowing) may be markers of concomitant cerebral small vessel diseases. In the Atherosclerosis Risk in Communities (ARIC) Study, a large community-based study of cardiovascular health in middle-aged people, the authors previously showed that retinal microvascular abnormalities, as documented from retinal photographs, are independently associated with incident stroke, cognitive impairment, and cerebral white matter lesions detected on MRI. The objective of this study was to examine the relation of retinal microvascular abnormalities and MRI signs of cerebral atrophy in healthy middle-aged people. A population-based, cross-sectional study involved 1,684 persons aged 51 to 72 years who had cerebral MRI and retinal photography in 1993 to 1995. Sulcal and ventricular size were quantified from the MRI scans and coded as grades 0 to 9, with sulcal widening and ventricular enlargement defined as grades 3 or higher. The presence or absence of retinopathy, microaneurysms, hemorrhages, and other characteristics were defined from retinal photographs using a standardized protocol. Generalized arteriolar narrowing was defined from a computer-assisted measurement of arteriolar diameters from digitized photographs. Persons with retinopathy had higher sulcal (P = .001) and ventricular (P = .03) grades than persons without retinopathy. After adjusting for age, gender, race, mean arterial blood pressure, diabetes, cigarette smoking, common carotid artery intima\Nmedia thickness, and other vascular risk factors, retinopathy was significantly associated with sulcal widening (odds ratio OR, 1.9; 95% confidence intervals CI, 1.2, 3.0) and ventricular enlargement (OR, 1.5; 95% CI, 1.0, 2.3). These associations persisted even in people without diabetes or hypertension (OR 1.9, 95% CI, 0.8, 4.4 for sulcal widening; OR 2.7, 95% CI, 1.2, 6.5 for ventricular enlargement). Other retinal arteriolar characteristics (arteriovenous nicking, focal and generalized arteriolar narrowing) were not related to sulcal or ventricular grade. The authors conclude that in healthy, middle-aged people, retinopathy is independently associated with sulcal and ventricular enlargement on MRI. This finding is compatible with the hypothesis that microvascular characteristics may influence the development of cerebral atrophic changes. Valerie Biousse