Photophobia


Photophobia is a symptom of abnormal intolerance to visual perception of light. As a medical symptom photophobia is not a morbid fear or phobia, but an experience of discomfort or pain to the eyes due to light exposure or by presence of actual physical sensitivity of the eyes, though the term is sometimes additionally applied to abnormal or irrational fear of light such as heliophobia. The term photophobia comes from the Greek φῶς, meaning "light", and φόβος, meaning "fear". Photophobia is a common symptom of visual snow.

Presentation

Severe or chronic photophobia, such as in migraine or seizure disorder, may result in a person not feeling well with eye ache, headache and/or neck ache. These symptoms may persist for days even after the person is no longer exposed to the offensive light source. Further, once the eyes have become sensitized to the offensive light source, they may become even more photosensitive with extreme pain occurring upon exposure to light.
Chronic photophobia may also adversely impact a person's ability to interact in social settings and the work place. Bright overhead lighting may make shopping a very painful experience for example, or render the patient dysfunctional in the work place. Office lighting intended to allow employees to get their work done may prevent one with photophobia from getting the job done and lead to such person getting fired. The physical and psychological effects of being in constant pain and overwhelmed with bright light that co-workers cannot perceive also stacks the deck heavily against one with photophobia having a successful career or even making a living. As such, photophobia can be a cruel, yet invisible disorder. Cultural factors associating darkness with evil, lack of interest or training among general practitioners or specialists, and a historical lack of medical research interest/support in the area have also tended to stigmatize and isolate photophobia patients, leaving them vulnerable to workplace discrimination or unfair treatment/job loss.

Causes

Patients may develop photophobia as a result of several different medical conditions, related to the eye, the nervous system, genetic, or other causes. Photophobia may manifest itself in an increased response to light starting at any step in the visual system, such as:
Common causes of photophobia include migraine headaches, TMJ, cataracts, Sjögren syndrome, Mild Traumatic Brain Injury, or severe ophthalmologic diseases such as uveitis or corneal abrasion. A more extensive list follows:

Eye-related

Causes of photophobia relating directly to the eye itself include:
Neurological causes for photophobia include:
The best treatment for light sensitivity is to address the underlying cause, whether it be an eye, nervous system or other cause. Notwithstanding recent progress in understanding light sensitivity of the eye, much more research is needed to better understand and treat photophobia, especially where it relates to migraine or other nervous system disorders. Genetic research into photophobia-related disorders is also needed. If the triggering factor or underlying cause can be identified and treated, photophobia may disappear.

Artificial light

People with photophobia may feel eye pain from even moderate levels of artificial light and avert their eyes from artificial light sources. Ambient levels of artificial light may also be intolerable to persons afflicted with photophobia such that they dim or remove the light source, or go into a dimmer lit room, such a one lit by refraction of light from outside the room. Alternatively, they may wear dark sunglasses, sunglasses designed to filter peripheral light, and/or wide-brimmed sun hat or a baseball caps. Some types of photophobia may be helped with the use of precision tinted lenses which block the green-to-blue end of the light spectrum without blurring or impeding vision.
Other strategies for relieving photophobia include the use of tinted contact lenses and/or the use of prescription eye drops that constrict the pupil, thus reducing the amount of light entering the eye. Such strategies may be limited by the amount of light needed for proper vision under given conditions, however. Dilating drops may also help relieve eye pain from muscle spasms or seizure triggered by lighting/migraine, allowing a person to "ride out the migraine" in a dark or dim room. A paper by Stringham and Hammond, published in the Journal of Food Science, reviews studies of effects of consuming Lutein and Zeaxanthin on visual performance, and notes a decrease in sensitivity to glare.

Disability

Photophobia may preclude or limit a person from working in places where offensive lighting is virtually ubiquitous, unless the person is able to obtain a reasonable accommodation. Some people with photophobia may be better able to work at night, or be more easily accommodated in the work place at night. Outdoor night lighting may be equally offensive for persons with photophobia, however, given the wide variety of bright lighting used for illuminating residential, commercial and industrial areas, such as LED lamps.