Transient ischemic attack (TIA) and minor strokes affect hundreds of thousands of Americans each year. Up to 20% of patients affected by TIA and minor stroke will have a new, often disabling, stroke or cardiovascular event within 90 days, with the majority of these new events occurring in the first few hours and days after the initial events. Significant research has been focused on creating validated, easy-to-use tools that provide clinicians with accurate estimates of stroke risk after TIA and minor stroke, but there is substantial room for improvement. Ophthalmology has an important opportunity to assist with this difficult problem because the ocular fundus is the only place where part of the central nervous system (CNS) and its associated microvasculature can be directly visualized non-invasively. Based on our preliminary data, we hypothesize that acute retinopathic and vasculopathic changes in the ocular fundus (optic nerve and retina) are not only biomarkers of acute CNS tissue injury, but provide severity information about other important stroke risk factors (e.g., hypertension and diabetes). We propose a prospective, observational cohort study to validate and replicate our early results in a fully-powered study of 760 subjects. We will assess ocular fundus abnormalities using non-mydriatic photography, which allows high quality photographs of the optic nerve and retina to be taken without dilation of the pupils.
Our aims are (1) to determine whether abnormalities of the ocular fundus are an independent predictor, above and beyond that of other clinical features and neuroimaging studies, of short-term (i.e., within 90 days) clinical outcomes (new stroke, cardiovascular events, and death) in patients presenting with TIA and minor stroke, and (2) to determine whether abnormalities of the ocular fundus among patients with suspected TIA differentiate patients with cerebrovascular diagnoses vs. those with non- cerebrovascular diagnoses. We will conduct the project at three Emory University-affiliated hospital's emergency departments and stroke services. Our project has the potential to translate our preliminary epidemiological findings into clinical care and improve the evaluation of TIA and minor stroke with a low-cost, universally available, but underutilized, aspect of the physical examination that when augmented by non- mydriatic fundus photography provides improved diagnostic capabilities and the potential for telemedical consultation when additional expertise is required.
Transient ischemic attack (TIA) and minor stroke are common neurological conditions that portend a high risk of a disabling stroke within hours and days. Determining who is at the highest risk for a new stroke after a TIA or minor stroke is difficult. This project investigates whether abnormalities in the eye are a marker of who is at highest risk of future stroke, using a relatively low-cost camera that allows photographs of the back part of the eye to be taken without dilation of the pupils.