flashes and floaters

flashes and floaters of the eye

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Floaters are those tiny spots, specks, flecks and "cobwebs" move with your eye, creating the impression that they are “drifting.” While annoying, ordinary floaters are very common and are not usually cause for concern.  Typically, floaters appear when the vitreous, the gel-like substance within the eye, breaks loose from the inner back portion of the eye the retina.  About 7 out of 10 people experience floaters at some point during their lives.  

Flashes of light, also known as photopsia, can occur for the following reasons:

The retina receives non-visual (mechanical) stimulation, which can happen when it is being tugged, torn or detached.  

Following a blow to the head, often called "seeing stars."  

They can appear as jagged lines in both eyes, often lasting 10-20 minutes. These types of flashes are usually caused by a spasm of blood vessels in the brain, which is called a migraine.  If a headache follows the flashes, it is called a migraine headache. However, jagged lines can occur without a headache. In this case, the light flashes are called an ophthalmic migraine, or a migraine without a headache.

Sometimes flashes of light are experienced with floaters. The sudden appearance of these symptoms could mean that the vitreous is pulling away from your retina or that the retina itself is becoming dislodged from the inner back of the eye, which contains blood, nutrients and oxygen vital to healthy function.  In cases of retinal tear or detachment, action must be taken immediately so that an eye surgeon can reattach the retina and restore function before vision is lost permanently.

The presence of a sudden onset of floaters and/or flashes is considered a medical emergency and should be thoroughly evaluated with a dilated eye examination as soon as possible.