Conditions in which there is a loss or reduction of transparency of the lens of the eye causing progressive loss of clarity and detail of images.
Clouding of the lens of the eye is a major cause of impaired vision in the United States may be either developmental or degenerative. Developmental occurs congenitally or early in life as a result of heredity, nutritional, or inflammatory disturbances. Degenerative is characterized by loss of transparency in a normally developed lens of the eye and is the result of changes due to aging, or the side effects of heat, X- rays, trauma, disease, or drugs. The major symptom of is a painless loss of vision and is corrected by extraction of the lens and fitting of visual prostheses.
The clouding of the natural lens of the eye (lens is located behind the iris and pupil).
A progressive disease in which the lens of the eye becomes cloudy, impairing vision or causing blindness.
A condition in which the lens of the eye gradually becomes hard and opaque.
Loss of transparency of the lens of the eye.
Acataract is an ocular disease of the lens (a flexible, trans¬ parent structure located posterior to the pupil and iris that focuses light rays on the retina) or of the connective tissue capsule that encloses it. Opacity (cloudiness) caused by a cataract can lead to decreased vision and may eventually result in blindness if left untreated; in fact, cataracts have been identified as the major cause of blindness and visual impairment in adults. Cataracts can occur in various areas of the lens and capsule; they may be located in the center of the lens (nuclear cataracts), in the area surrounding the nucleus (cortical cataracts), or within the capsule (posterior subcapular cataracts; Gale Encyclopedia of Medicine).
Loss of transparency in the lens at the back of the eye.
Eye disorder in which the lens becomes less transparent (more opaque) so that light rays cannot reach the retina and there is progressive painless loss of vision. Most cataracts are caused by degenerative changes after age 50, but some may be caused by trauma to the eye or exposure to certain chemicals; some are hereditary and some congenital (due perhaps to viral infection during pregnancy). Treatment is removal of the lens and use of special contact lenses or eyeglasses or the implantation of an intraocular lens (lOL); in children soft cataracts may be removed by fragmentation (via ultrasound) and drainage.
Clouding of the lens of the eye; treated by surgical removal and replacement with a prosthetic intraocular lens.
A cloudiness or opacity in the normally clear lens of the eye. The lens is made of water and protein, which are arranged in a specific way to preserve the clarity of the lens. A cataract forms when alterations in the proteins occur and form a cloudy or opaque area in a portion of the lens. Over time, the cataract tends to grow and affect more and more of the lens. In most cases, cataracts affect both eyes, although the condition may be more advanced in one eye than the other.
Any opacity in the lens of the eye resulting in blurred vision. The commonest type is senile cataract, seen frequently in the elderly, but some cataracts are congenital, while others are due to metabolic disease, such as diabetes, galactosemia, and hypocalcemia. Cataracts may also result from direct or indirect injury to the lens and prolonged exposure of the eye to infrared rays (e.g. glass-blowers cataract) or ionizing radiation. Minor degrees of cataract do not necessarily impair vision seriously.
An opacity of the lens of the eye, usually occurring as a result of aging, trauma, endocrine or metabolic disease, intraocular disease, or as a side effect of the use of tobacco or certain medications (such as steroids). Cataracts are the most common cause of blindness in adults.
A partial or complete opacity of one or both eyes, especially an opacity impairing vision or causing blindness.
A gradual development of opacity or cloudiness in the lens of the eye occurs, leading to the obstruction of light transmission to the retina.
Cataract is a condition characterized by the loss of transparency in the lens of the eye due to changes in its protein fibers. In its advanced stages, the front portion of the lens becomes densely opaque; however, cataracts do not result in complete blindness. While a densely opalescent lens still permits the transmission of light, the clarity and sharpness of the visual image deteriorate. Cataracts typically affect both eyes, although one eye is usually more severely impacted than the other.
The prevalence of cataracts is quite common among individuals aged 65 and above, with nearly everyone in this age group experiencing some degree of the condition. It can be regarded as a natural aspect of the aging process. Additionally, regular exposure to ultraviolet light raises the risk of developing cataracts.
Cataracts can also arise from eye injuries, especially when foreign objects penetrate the lens. Furthermore, individuals with diabetes mellitus frequently experience cataracts, and if blood sugar levels are inadequately controlled, the condition may develop at an earlier age. Prolonged usage of corticosteroid medications can also be a contributing factor to the development of cataracts.
The occurrence of congenital cataracts can be attributed to multiple factors. Infections contracted by the mother during early pregnancy, particularly rubella (German measles), can contribute to congenital cataracts. Additionally, certain drugs taken during pregnancy may have toxic effects and lead to the development of cataracts in newborns. Congenital cataracts may also be associated with Down’s syndrome or the rare genetic disorder known as galactosaemia.
Cataracts are characterized by their painless nature and primarily result in visual symptoms. The onset of these symptoms is often gradual, with initial effects potentially impacting night driving. Over time, there is a slow and progressive decline in visual acuity, leading to increased blurring of vision. Individuals may also experience a shift towards nearsightedness and observe disturbances in their perception of colors.
In cases where vision has been considerably impaired, cataract surgery is carried out to eliminate the affected lens and replace it with an artificial implant. As long as the eye is in good overall health, cataract surgery typically yields outstanding outcomes, delivering excellent results.
The cloudy appearance of the eye’s lens or its capsule is known as a cataract. This condition is often seen in older individuals as a sign of aging, but it can also occur in people of all ages due to illness. Cataracts are one of the leading causes of impaired vision or blindness in the elderly. In the past, it was believed that a cataract had to reach a certain stage of “ripeness” before it could be surgically removed. However, this notion has been debunked. Modern surgical techniques prioritize early removal of the cataract to prevent irreversible loss of vision. Delaying surgery until the last possible moment can lead to suboptimal visual outcomes, even after the cataract is removed. Early removal followed by the use of appropriate eyewear can effectively preserve eyesight.