Search results
Results From The WOW.Com Content Network
Photophobia is a medical symptom of abnormal intolerance to visual perception of light. [1] 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, [2] though the term is sometimes additionally applied to abnormal or irrational fear of light, such as ...
Intensity of light (photophobia, sunburn, skin cancer) [1] [2] [3] Wavelength of light (in lupus, urticaria) Rapid flickers in intensity of light may trigger or aggravate photosensitive epilepsy, epileptic seizure, or migraine headaches. [4] Conditions that may include sensitivity to light include vertigo and chronic fatigue syndrome.
Photosensitivity is the amount to which an object reacts upon receiving photons, especially visible light. In medicine, the term is principally used for abnormal reactions of the skin, and two types are distinguished, photoallergy and phototoxicity .
Symptoms include recurring attacks of severe acute ocular pain, foreign-body sensation, photophobia (i.e. sensitivity to bright lights), and tearing often at the time of awakening or during sleep when the eyelids are rubbed or opened. Signs of the condition include corneal abrasion or localized roughening of the corneal epithelium, sometimes ...
This means that the brightest and the darkest light signal that the eye can sense are a factor of roughly 1,000,000,000 apart. However, in any given moment of time, the eye can only sense a contrast ratio of 1,000. What enables the wider reach is that the eye adapts its definition of what is black.
What’s the difference between mineral and chemical sunscreen? The main differences are their ingredients and how they protect against the sun’s rays.
Photosensitive epilepsy (PSE) is a form of epilepsy in which seizures are triggered by visual stimuli that form patterns in time or space, such as flashing lights, bold, regular patterns, or regular moving patterns. PSE affects approximately one in 4,000 people (5% of those with epilepsy).
Type III (aka hepatic photosensitivity) is the most common type of photosensitivity reaction seen in animals. [2] In this type, the photodynamic substance is phylloerythrin, a derivative of chlorophyll produced in the body. Normally, phylloerythrin is secreted into the intestine by the biliary system and excreted through the feces.