Cataract is widely known as a disease of old age. Despite this misconception, cataracts may occur at birth or in young children as a result of various factors, notably genetics and trauma. Although they are most commonly diagnosed in the elderly, they often start to develop during middle age and slowly progress towards blindness if left untreated. The disease is responsible for more than half of the blindness cases in severely underdeveloped countries due to the lack of access to proper medical care.
What is cataract and how does it occur? Cataract is a degenerative eye disease characterized by the gradual clouding of the transparent crystalline lens of one or both eyes which eventually leads to vision impairment or blindness. The clouding is progressive and happens because of a protein buildup in the lens of the eye preventing light from passing through and reaching the retina. This buildup has been described as having a yellowish or brownish color. Over time, more proteins add to the initial buildup, leading to complete blindness.
What does cataract look like? Cataracts look like opaque, grayish spots somewhere on the pupil or iris. If left untreated, these spots will progress until they cover the entire pupil or iris (the colorful part of the eye surrounding the pupil). In reality, it’s not the pupil or iris that becomes opaque, but the lens behind them, called the crystalline. The crystalline is normally transparent because it needs to let light pass through and reach the retina at the back of the eye. However, various factors may cause proteins to concentrate in certain areas of the crystalline, slowly turning it opaque.
What causes cataract?
The most common causes that lead to the development of cataract include:
1) Old age. The lens of the eye will degrade over time as a result of the natural process of aging. Exposure to toxins, ultraviolet radiation from sunlight, disease etc. may add up, compromising eye health and further favoring the development of cataract.
2) Injury and trauma to the eye. Blunt trauma to the eye in the form of electric shock, radiation, piercing by sharp objects, but also eye surgery for the correction of other vision problems may lead to lens injury, inflammation and whitening. The whitened parts of the lens never recover, leaving the lens partially opaque as they don’t allow light to pass. In time, they may progress and favor cataract formation. Some types of injury to the eye cause star-like or rosette-like cataracts.
3) Genetics. Cataracts occurring in newborns and young children can be caused by developmental problems brought on by genetic disorders such as Down syndrome, Turner’s syndrome, Conradi syndrome, Alport’s syndrome etc. Cataracts may also be hereditary, in which case they may develop later in life.
4) Certain pharmaceuticals. Cortisone, nicotine-based pharmaceuticals, some diuretics, cholesterol medication etc. can encourage cataract development either directly or indirectly.
5) Smoking. Research suggests that nicotine and other toxic compounds in cigarettes and tobacco can significantly increase the risk of developing cataract. Air pollution may be another influential factor.
6) Disease. Diabetes, hyper and hypoparathyroidism, galactosemia, genetic diseases, obesity, high blood pressure etc. can increase the risk for cataract. Other eye diseases and conditions such as uveitis or retinal detachment can encourage cataract development, especially following surgery to correct them.
7) Radiation. Ionizing radiation such as X-ray, UVB or gamma rays can damage the lens of the eye and, in time, lead to cataracts. Wearing sunglasses to protect the eyes from direct sunlight is believed to help reduce overall cataract risk.
Types of cataract. According to age, cataracts may be classified as follows:
1) Subcapular (affecting the back of the lens).
2) Nuclear (central).
3) Cortical (affecting the outer layer of the lens, progressing inwards).
Other classifications. Depending on the size of the area affected, cataracts may be partial of complete (covering the entire lens, which is about the size of the iris). As far as their evolution is concerned, they may be stagnant or progressive. Depending on the type of protein deposits that form of the lens, they may be soft or hard.
Signs and symptoms
What are the signs and symptoms of cataract?
1) Blurry, foggy or cloudy eyesight, fading colors and overall poor visual acuity.
2) Glare (when looking at light bulbs, headlights and so on).
3) Improved near vision lasting a short time.
4) Poor night vision.
5) Seeing double or multiple images.
6) Changing glasses constantly.
7) The appearance of a grayish spot somewhere on the pupil or iris.
Treatment options for cataract may vary widely from person to person, depending on the how advanced the disease is and how it impacts normal daily life. As long as the protein buildups remain somewhat transparent, your doctor might recommend wearing glasses or enjoying better lighting. Surgery is recommended when vision becomes impaired.
When should you get cataract surgery? Doctors generally recommend having surgery when the opaque protein buildups on the lens prevent us from performing routine activities such as driving.
How does cataract surgery work? The procedures seek to take out the opaque lens and replace them with a transparent artificial one with the same function. Surgery is both effective and painless, with a relatively high success rate. However, complications such as infection, retina detachment, eye floaters or poor vision may occur in some patients.
How long does cataract surgery take to heal? You can go home the same day you had the surgery, but full recovery might take around 4 weeks.
Good to know. It would appear that managing our diet so as to include several important nutrients such as vitamin C and other antioxidant compounds such as lutein and zeaxanthin our diet may help reduce our risk for cataract. Vitamins A and E are believed to help as well. Wearing sunglasses to protect our eyes from sunlight ultraviolet radiation is also recommended. Just as important is having an annual eye check up for early detection of potential problems.
The main cause of cataract is old age. However, we don’t all age in the same rhythm which would explain why some people start developing cataract and other age-related diseases early on, at just 40 or 50 years old, while others enjoy good eyesight and overall good health well beyond old age. Despite the genetic and age-related aspects of this disease, taking good care of ourselves is highly beneficial for our long term health and may play a role in preventing cataract as well.