Overview:
- A cataract is a clouding of the normally clear lens of your eye making vision unclear.
- Cataracts happen slowly and painlessly.
- They happen either in one or both eyes, and one eye does not affect the other.
- The only treatment for cataracts is surgery. It is generally a safe and effective solution.
- Preventing cataracts involves getting your eyes checked regularly and having your chronic diseases under control.
Lens:
The lens, where cataracts form, is positioned behind the colored part of your eye (iris). It is normally transparent. The lens focuses light that passes into your eye, producing clear, sharp images on the retina — the light-sensitive membrane in the eye, allowing clearly seeing near and far objects. In a normal eye the light passes through the transparent lens into the retina where light is changed into nerve signals to be sent to the brain via the optic nerve.
What is a cataract?
Cataract is a clouding of the normally clear lens of your eye. For people who have cataracts, seeing through cloudy lenses is a bit like looking through a frosty or fogged-up window. The lens starts to lose its clarity gradually until it becomes completely cloudy. Clouded vision caused by cataracts can make it more difficult to read. It can happen to people of any age and in one or both eyes.
Names: Cataracts
Types of cataracts:
- Cataracts affecting the center of the lens (nuclear cataracts): It is the most common type of cataracts and associated with older age. In this type the lens gradually turns more densely yellow and further clouds your vision. At first, it may lead to a temporary improvement in seeing near objects, such as the pages of a book.
- Cataracts that affect the edges of the lens (cortical cataracts): It is the layer surrounding the nucleus of the lens. The opacity of the eye lens begins as a white spot and progresses slowly, until it interferes with the light passing through the lens and makes vision blurry.
- Cataracts that affect the back of the lens (posterior subcapsular cataracts): This type of opacity can cause problems with reading, sensitivity to light, or seeing halos around light. It develops relatively faster than other types and its symptoms can appear within only a few months.
Cause:
As you age, the lenses in your eyes become less flexible, less transparent and thicker. Age-related and other medical conditions cause tissues within the lens to break down and clump together, clouding small areas within the lens. Babies rarely develop cataracts at birth. They are usually due to heredity or infections the mom has during pregnancy (e.g., rubella).
Risk factors:
- Old age
- Excessive exposure to ultraviolet radiation
- Eye trauma or injury
- Diabetes
- Hypertension
- Prolonged use of corticosteroid medications
- Previous eye surgery
- Smoking
Symptoms:
They vary from a person to another. They include:
- Painless and gradual vision weakening
- Cloudy unclear vision
- Sensitivity to bright light
- Seeing halos surrounding lights
- Difficulty seeing at night
- Repeated change of glasses or contact lenses
- Gradual change of lens into white, or brown in advanced stages.
These symptoms can also signal another eye problem. See your doctor for an accurate diagnosis.
When to see a doctor?
See your doctor if you notice any changes in your vision such as halos surrounding lights or difficulty driving at night due to headlight glares, eye pain, or sudden headaches.
Complications:
Total or partial loss of vision in the long run.
Diagnosis:
- Clinical examination
- Medical history
- Getting eye tests conducted, such as: Visual acuity test, retinal and lens assessment, tonometry, fundoscopy, and a red reflex test. An absent reflex means there is a degree of opacity.
Treatment:
The only treatment is surgical intervention: A popular surgical intervention involves removing the clouded lens and replacing it with a clear artificial lens. The artificial lens, called an intraocular lens, is positioned in the same place as your natural lens. It remains a permanent part of your eye. This surgery can be done in many different ways, depending on each case.
Prevention:
No studies have proven that there are sure ways to prevent cataracts from forming or slow their progression. Nevertheless, the following tips may be helpful:
- Get regular eye tests.
- Quit smoking.
- Follow a treatment plan for health problems like: Diabetes and other diseases.
- Choose a healthy diet that contains vitamins and antioxidants.
- Wear sunglasses that block UV rays.
FAQs:
- Are cataracts hereditary?
- Cataracts can be partially hereditary or the result of chronic eye inflammations. They could also be the result of some illnesses like diabetes.
- If I have cataracts does it mean that I will be completely blind?
- If you do not receive proper treatment by having the affected lens replaced, your condition might result in blindness. After your surgery your vision will go back to normal.
- Do my cataracts have to be in an advanced stage for me to get the surgery?
- With the latest developments in microscopic eye surgeries and with the help of phaco devices, it is no longer necessary to wait. The operation can be performed at any stage of cataract.
Myths & Truths
- Myth: Cataract is contagious.
- Truth: Cataract is contagious. One eye with cataracts cannot infect the other.
Clinical Education General Department