What Causes A Sensitivity To Light?
Meningitis
Meningitis is a condition characterized by the inflammation of the protective membranes that surround the brain or meninges. Along with migraines, sensitivity to light is one of the first symptoms to manifest in many meningitis patients. Light sensitivity can develop because of the migraines produced by the inflammation of the meninges and swelling of surrounding tissues. Light sensitivity may also develop if the tissues in the brain swell and cause an individual's optic nerve to become swollen and damaged.
The optic nerve is a bundle of nerve fibers responsible for the transmission of visual information from the retina to the visual processing centers of the brain. Issues with general visual performance is another mechanism that implicates meningitis as a cause of photophobia. Post-meningitis sensitivity to light can last for as long as months or years following the infection due to a chronic headache disorder or permanent optical nerve damage.
Cataracts
Light sensitivity is usually not apparent in the early stages of cataract development. However, cataracts are progressive and eventually cause a cloudy, abnormal growth on the eye lens. These cloudy growths on the eye lens can cause a patient to have trouble with their vision. Cataracts can also produce what is referred to as a disability glare in an affected individual. Disability glare is a light sensitivity that occurs when an individual has an eye disease or condition that adversely affects their visual function.
Disability glare is an increased sensitivity to normal lighting conditions that happens because the patient's eyes are not able to adjust to minor changes in light settings properly. Cataracts on the lens of the eye cause the incoming light to disperse and scatter, rather than focusing on the back of the eye onto the retina. This malfunction that occurs with the way a patient's eye takes in light and adjusts to light changes can cause them to have difficulty around any source of light that is only a mild degree of brightness.
