Cataracts are one of the most common eye diseases that cause blindness, so what are the obvious symptoms of cataracts? Because there are no obvious symptoms at the onset of cataracts, many people do not detect them early enough to miss the best time to treat them, so knowing the obvious symptoms of cataracts is the key to early treatment.
The clouding of the lens is called cataract. Aging, heredity, metabolic abnormalities, trauma, radiation, poisoning and local malnutrition can cause damage to the lens capsule membrane, increasing its permeability and losing its barrier effect, or lead to disorders in lens metabolism, causing degeneration of lens proteins and forming cloudiness.
Cataracts often develop in middle age, i.e. after 45 years old. In the early stage, the visual acuity is so faint that it cannot be detected by oneself, but the visual acuity of both eyes (distance vision and near vision) gradually decreases at the same time, and only when the visual acuity decreases to a certain degree does it attract attention. Middle-aged people should pay attention if they have mild visual impairment, or their eyes are easily fatigued, or there is a black spot in front of their eyes and fixed, or there are clouds in front of their eyes and they can’t see clearly, or there is double vision (diplopia).
In addition, some people wear presbyopic glasses at an early age, but occasionally see near things clearly without them. Other early signs of cataract include cloudy crystal, low vision when looking at objects, low color vision when looking at colors, poor dark adaptation ability, and longer time required to see objects clearly.
According to the clinical survey, the high prevalence of cataracts is found in people who are sensitive to sunlight exposure. In other words, people with suspicious cataracts can be detected earlier by the signs of changes on the skin after exposure to sunlight. In the summer, some people get red spots or small blisters on their skin when exposed to the sun. These people generally have clearer skin that is sensitive to ultraviolet light and therefore susceptible to sunburn. Ophthalmologists have found that some of these people who are susceptible to sunburn have bodies that produce oxygen radicals when exposed to the sun, a substance that can cause skin damage.
If these people are exposed to too much sunlight, oxygen free radicals will also be produced locally, resulting in impaired metabolism of the eye lens and a gradual loss of crystal clarity, resulting in clouding of the lens and cataract formation. In these people who are sensitive to sunlight, the incidence of cataracts can be 30% to 40% higher than that of the general population, and the age of onset can be 5 to 10 years earlier.