Seeing flashes of light may be an indication of a serious medical issue. Here are some of the medical conditions that can trigger light flashes.
The retina is the part of the eye that contains light-sensitive cells and generates nerve impulses that transmit signals from the eye to the brain. In short, you only see what you see because the retina is able to capture light signals and transmit them to your brain. Therefore, a malfunction in your retina's normal operations may interfere with what you see. For example, damage to the retina (through disease, accident, or old age) can interfere with signal transmissions to the brain and make you see flashing lights as a result of jumbled signals.
A migraine is a severe headache or pain, usually in one side of the head, which may be accompanied by other symptoms such as vomiting, light sensitivity, tingling, and light flashes, among others. The exact causes of migraines are not well understood, but there is compelling evidence that environmental and genetic factors play a vital role in their occurrence. If your migraine is accompanied by flashes of light (among other visual disturbances), then it is given the name ocular migraine.
Meningitis is an infectious disease that inflames the meninges, a protective layer of tissue that protects both the brain and the spinal cord. Bacterial meningitis is caused by bacteria while aseptic meningitis is caused by other things other than bacteria (such as fungi or various viruses). Aseptic meningitis has many symptoms that include visual disturbances such as flashes of light and sensitivity to light. This makes sense given that meningitis can interfere with the signal transmission or processing in the brain leading to the visual disturbances.
Posterior Vitreous Detachment
The vitreous is a gel-like substance that fills the interior of your eyes and is in contact with other parts of the eyes, including the retina. The light signals that enter your eyes pass through the posterior vitreous to the retina, so damage to this part of the eye may also affect your vision. Eye diseases, injuries, or old age are some of the things that can cause the posterior vitreous to separate from the retina, and even a small separation can end up causing flashes of light in your eyes.
Therefore, you need to see an eye doctor as soon as possible if you are seeing flashes of light. That way you can know whether the flashes are due to an eye condition or another medical issue and get the relevant treatment. For more information, contact your local optometrist.