Flashes can occur when there is traction or tugging on the retina. This usually occurs during a posterior vitreous separation when the gel in the central cavity of the eye shrinks and pulls away from the retina. The vitreous gel may be more adherent to the retina in some locations, leading to tugging on the retina and possible flashing lights. Retinal tears and retinal detachment can be the cause of flashes, although many other retinal conditions can lead to flashes. Any patient with sudden new onset of flashes should have their retina examined to determine the cause and ensure that proper treatment is initiated.