Associations between findings on cranial magnetic resonance imaging (MRI) and retinal photographs have been described mostly in middle-aged people. In the Cardiovascular Health Study, 1,717 elderly participants underwent MRI and retinal photography between 1991 and 1999. Associations were sought between MRI findings and four findings of retinal microvascular disease: retinopathy, focal arteriolar narrowing, arteriovenous nicking, and the arteriovenous ratio--the last based upon semiautomated measurements of arterioles and venules. After controlling for age and gender, the authors found associations between MRI findings and the smaller arteriovenous ratio (per standard deviation decrease): prevalent infarcts (odds ratio = 1.18, 95% confidence interval: 1.05, 1.34; p = 0.007), white matter grade (regression coefficient, 0.093; p = 0.011), incident infarct (odds ratio = 1.26, 95% confidence interval: 1.09, 1.46; p = 0.002), and worsening white matter grade (odds ratio = 1.12, 95% confidence interval: 0.98, 1.29; p = 0.09). Arteriovenous nicking was also associated with prevalent (odds ratio = 1.84, 95% confidence interval: 1.23, 2.76; p = 0.003) and incident (odds ratio = 1.84, 95% confidence interval: 1.15, 2.94; p = 0.011) infarcts. Adjustment for hypertension and diabetes had minimal effect. Evidence of small vessel disease in the retina increases the likelihood of finding it in the brain. Associations were less prominent in this elderly population than have been described in middle-aged people. [ABSTRACT FROM AUTHOR]