The flashing sensation is mostly caused by vitreous traction irritating the retina, which can easily occur in patients with vitreous liquefaction or posterior detachment, and can also occur in patients with a history of ocular trauma due to localized vitreous liquefaction traction and scar traction at the injury site. If the vitreous pull or scar pull breaks the retina, it can cause retinal fissures, hemorrhage or detachment. However, the flash does not always cause retinal detachment, and most of them will be released gradually with time and the flash will disappear. Therefore, the fundus should be examined when there is a flash sensation and treated promptly when there is a fundus lesion (degeneration, fissure, hemorrhage, detachment, etc.). If there is no fundus lesion or after laser treatment of fundus lesion, continue to observe and follow up when the flash sensation worsens, vision changes and visual field changes. Minimize head movement, avoid pressing the eyeball and rubbing the eye when flashing sensation occurs to avoid retinal damage caused by aggravated pulling. It is also important to pay attention to the conservation of eye use and avoid visual fatigue. Your case is roughly due to minor contusion and visual fatigue caused by a slight clouding of the vitreous, pay attention to rest, and take appropriate drugs to improve blood circulation and promote absorption of the fundus can be alleviated. In the presence of obvious under vision or large dark shadows need to promptly go to the ophthalmology review.