FOTO-TIA was a cohort study of adult patients with a NIH Stroke Scale ≤ 3 admitted to three EDs’ observation units for an accelerated diagnostic protocol for suspected TIA or stroke. Clinical and imaging results were recorded prospectively. Non-mydriatic fundus photographs were obtained as part of the accelerated diagnostic protocol and reviewed for retinal microvascular findings, defined as retinal hemorrhages, cotton wool spots, retinal emboli or occlusions, hard exudates, or microaneurysms. A neurologist rated the probability each patient’s presentation (masked to fundus photography) represented a CVE on a visual analogue scale.

395 patients were enrolled (median age: 57 years (interquartile range [IQR]: 50–66); 219 (55%) women; 253 (64%) black; 34 (9%) retinal microvascular findings present; median CVE probability assessment 22% (IQR: 5–100)). Controlling for the individual components of the ABCD² score (age, systolic and diastolic blood pressure, clinical symptoms, duration of symptoms, and diabetes) and presence of a MRI-DWI positive lesion, any retinal microvascular finding increased the CVE probability assessment by 15.6% (95%CI: 4.2–27.1%, p=0.008). Excluding patients with a DWI positive lesion (i.e., those with definite stroke), any retinal microvascular finding increased CVE probability assessment by 21.8% (95%CI: 6.1–37.5%, p=0.007).

Retinal microvascular findings assessed by nonmydriatic ocular fundus photographs during the evaluation of suspected TIAs in the ED are an independent factor differentiating TIA and stroke from mimics.