When you experience a flash of light it is usually caused by a couple different things. One of the most common ways is that the retina in the back of the eye gets stimulated by some type of force. When that force occurs it sends a signal to your brain that you perceive is a flash of light. You might notice if you gently touch the top of your eyelid and push on your eye you see a spot in your vision on the opposite side of where you pushed. That is due to the retina being stimulated by your finger on the eyelid.
The “floater” that you see actually occurs just in front of the retina in the vitreous. The vitreous is the jelly-like structure that is in between the lens and the retina. It gives the eye its round shape and it is attached to the retina all around. As you age though, the vitreous becomes less solid and more like a liquid. When this occurs, the vitreous tends to shrink in upon itself. As it shrinks, the areas where the vitreous is attached can tug on the retina and will eventually pull away from the retina. The tugging on the retina is the flash of light you experience and the floaters you see are the particles of vitreous that are creating a shadow on your retina. You can get a few particles of vitreous and only get a few tiny floaters or you can have the vitreous completely let go and have what we call a Posterior Vitreous Detachment (PVD). That is when the vitreous completely detaches from the retina and you experience a large shadow that usually creates a large annoyance in your vision.
In the vast majority of cases, vitreous floaters and/or PVD do not cause any problems with your eyes besides the annoyance if the floater occurs in the center of the eye. Eventually your brain will ignore the floaters or they will shift more to your side vision and you will not notice them as frequently. In some cases though, when the vitreous lets go from the retina it can create a hole or tear in your retina. That hole or tear could develop into a Retinal Detachment which is a severe sight threatening condition that needs immediate action. If you experience a new onset of flashes or floaters in your vision, please call our office for an appointment immediately (860) 233-2020.