Ocular pain refers to any discomfort in the area of the eye and may affect to one or both eyes. It is both a widespread disorder and a symptom with a proved negative impact on patient’s quality of life. Due to current life-style, the number of people affected by ocular pathologies related to altered ocular sensitivity is very high, and it is expected to increase with aging of population.
Ocular pain can be associated with ocular dryness, contact lens overuse, ocular injuries, conjunctivitis, eye surgery or headache. Symptoms accompanying ocular pain include itching, burning and irritation.
Cornea and its overlying tear film are essential to focus the images. Both structures define the primary barrier of the eye to noxious stimuli that may lead to ocular pain.
The cornea is a transparent “window” covering the front of the eye. It is one of most sensitive tissues of the body as it is densely innervated.
The tear film has three main components or layers: mucous, aqueous, and lipid which are spread over the ocular surface by the action of blinking. Functions of the tear film include: lubricating the ocular surface and eyelids, supplying nutrients to the ocular surface, removing foreign material and microbes as well as offering protection against pathogens by means of antibacterial substances as well as promoting tissue maintenance and wound healing of the ocular surface.
Any alterations in the cornea and/or in the tear film may lead to ocular pain. Currently there is not a specific treatment for this condition that it is often undiagnosed, overlooked and confused with other conditions which may lead to long term-complications.