The patient was a 24 year-old healthy man who complained of a small blind spot in the right eye for several months, ever since he stared at the sun. The visual acuity was 20/25 OD and 20/20 OS. On examination, there was a pinpoint RPE disturbance in the central fovea of the right eye, which is difficult to see on the fundus photograph. The OCT shows a small central disruption of the ellipsoid zone. What is the most likely diagnosis?