Sudden blackness in front of the eyes is a symptom of ischemia of the ophthalmic artery, which is often one of the manifestations of transient total cerebral ischemia. In this case, it is recommended to improve the following examinations: 1) blood routine: clarify the hemoglobin content and the presence of anemia; 2) blood pressure examination: if necessary, perform 24-hour ambulatory blood pressure monitoring to clarify the presence of postural hypotension; 3) electrocardiogram examination: if necessary, perform 24-hour ambulatory electrocardiogram examination to clarify the presence of arrhythmia and exclude sick sinus syndrome, arrhythmia often leads to reduced blood supply to the heart and causes 4. Cranial magnetic resonance imaging and magnetic resonance angiography: to clarify whether there are ischemic changes in the brain and whether there is narrowing or occlusion of blood vessels, resulting in insufficient blood supply to the brain. After the above causes are identified, targeted treatment will be carried out.