Flashes of light can occur with or without floaters. Flashes are usually caused by the vitreous body tugging on the retina. This often occurs as the vitreous body shrinks with age. Some flashes are more apparent in dim lighting. Flashes in bright light can indicate a retinal tear and these should be looked at quickly to prevent fluid entering a retinal tear and detaching the retina. You should be examined promptly if you develop these types of flashes, any black curtains, shadows or a sudden decrease in your vision. If you have any of these symptoms you may need to make an appointment urgently.