Sudden blindness of the eyes for a few seconds, often occurs under a violent rise, or a violent lifting of the head, mainly due to insufficient blood supply, a violent rise, or lifting of the head causes postural hypotension, and the blood pumped from the heart does not supply the eye area, resulting in insufficient blood supply to the retina, and produces blindness, clinically known as a transient blackout. If it is a young person, and it is often transient, there is no positive significance, and observation is sufficient. In the case of the elderly, it is recommended to check the ultrasound of the carotid artery, as well as the cerebral blood flow, to check the carotid artery, or the cerebral blood vessels for plaque, if there is plaque, or other obstruction conditions, or thrombosis, to promptly seek medical advice to rule out the possible causes of insufficient blood supply.