Vascular retinopathies can represent a sentinel event for serious systemic illness. As such, once the diagnosis of a vascular retinopathy is made or suspected, careful examination and testing for the underlying cause is critical. For patients with ischemic retinopathy, secondary prevention of further vascular insults like stroke can prevent significant morbidity. Identification of these processes can be challenging for the emergency provider given the heterogeneity of the descriptions of symptoms by patients. The experience of visual changes described by patients overlaps between diagnoses. Therefore, maintaining a broad differential diagnosis with a systematic approach to the complaints is important to prevent future events or progression of vision loss.

The American Heart and National Stroke Associations have amended the definition of stroke to include brain, spinal cord, or retinal cell death attributable to ischemia. As such, patients with acute vascular retinopathies are evaluated similarly to patients experiencing other stroke syndromes, including an assessment of risk factors. For all patients with a complaint of visual disturbances, the emergency provider should obtain a thorough medical history, including past ophthalmologic history, medications, and history of similar problems in the past. Focusing on the present illness, it is important to clarify certain key elements: onset of symptoms, monocular or binocular symptoms, duration of symptoms, associated symptoms (eg, headache or neck pain), and neurologic deficits. Furthermore, because GCA is associated with vascular retinopathies, a review of systems for this disease is critical. These patients are over age 50 and may report a history of jaw claudication, headache (particularly in the region of the temporal artery), tenderness of the scalp, constitutional symptoms, arthralgias, and fever (see Chapter 49). The physical examination will focus primarily on the eye, including a thorough examination of the retina, usually performed by an ophthalmologist after pupillary dilation. When GCA is suspected, measurement of inflammatory markers is recommended (erythrocyte sedimentation rate [ESR], C-reactive protein [CRP], and platelets).

Visual acuity and an assessment of the visual fields may uncover deficits. A comprehensive neurologic examination including cranial nerves is warranted. Given the association with underlying vascular disease, evaluation of the carotid arteries for bruits or evidence of other vascular disease on examination is important. Auscultation of the heart and assessment with electrocardiogram may identify a causative dysrhythmia like atrial fibrillation.