Light sensitivity

04/04/2022

Our optical system enables our eyes to see, yet their inherent characteristics and some pathologies can cause us discomfort in the light. When this sensation is incapacitating, it is called photophobia. Our eye has different parts that help to direct the light toward the retina: the cornea, iris and crystalline lens.

Any anomaly in them can distort the rays of light, causing discomfort. The iris is a specific case, because despite being completely healthy, it can cause problems. This is due to the fact that lighter-coloured eyes or larger pupils are prone to suffering from this bothersome symptom. Common situations like stress can also cause our pupils to be more open than normal. In addition, individuals can be affected by different light sensitivities despite the fact that they have the same anatomy and they are subjected to the same environmental conditions. This situation is probably due to psychological and neurological factors.

Illnesses

There are some illnesses that cause a greater sensitivity to light. Perhaps the most common include keratitis, cataracts and internal inflammation of the eye.

▶ Keratitis are conditions of the eye's surface, specifically the cornea. There are different types. The most common are inflammatory and infectious, and even those caused by dry eye or physical damage which sometimes happens through the use contact lenses.

▶ Cataracts are caused by a loss of transparency in the crystalline lens which is the natural lens that helps us to see at a long distance and read at a short distance before our eyes become tired. In these cases, the symptomatology is varied, but many of our patients complain of photophobia in specific light conditions, for example, while driving at night. 

▶ Internal inflammation of the eye manifests itself in different ways and for many reasons. This situation is called uveitis and its common denominator is myosis or shrinking of the pupil, photophobia and visual loss. Its causes vary and usually require a good diagnosis. Sensitivity to light can be mitigated with sunglasses in cases where there are no pathologies and in cases where there are, a thorough eye examination should be undertaken and corresponding treatment provided.

 Dr. José Lamarca Mateu, opthalmologist at the Barraquer Ophthalmology Centre