Most cataracts develop slowly and do not affect vision in the early stages but in the later stages they can significantly interfere with vision.
If impaired vision affects the normal lifestyle of the person, surgery for cataract removal may be required which is generally a safe and effective procedure.
Cataracts commonly affect distance vision and glare.
Types of cataracts
- Nuclear cataract occurs in the centre of the lens.
- Cortical cataract begins as whitish, wedge-shaped opacities or streaks on the outer edge of the lens.
- Sub capsular cataract starts as a small, opaque area just under the capsule of the lens near the back of the lens.
Risk factors
Risk factors for developing cataracts include:
- Age
- Family history of cataract
- Diabetes
- Previous eye injury or inflammation or previous eye surgery
- Prolonged use of corticosteroids
- Excessive exposure to sunlight or ionizing radiation
- Smoking
Symptoms
Signs and symptoms of cataracts include:
- Clouded, blurred or dim vision
- Difficulty with night vision
- Sensitivity to light and glare
- Halos around lights
- The need for brighter light for reading and other activities
- Frequent change of spectacles or contact lens
- Double vision in a single eye
Tests and diagnosis
A clinical eye examination is necessary to make a diagnosis of cataract which includes several tests:
- Visual acuity test refers to the sharpness of vision or how clearly one can see an object. It is done with the help of a chart with progressively smaller letters from top to bottom (Snellen’s chart).
- Slit-lamp examination allows the doctor to see the structures at the front of your eye under magnification.
- Sensitivity to light and glare
- Retinal examination is done with a slit lamp or a special device called an ophthalmoscope.
Treatments and drugs
Cataracts cannot be cured with medications, dietary supplements, exercise or optical devices.
The only effective treatment for cataracts is surgery which involves removal of the clouded lens and replacing it with a clear lens implant. Occasionally cataracts are removed without reinserting implant lenses and the vision defect is corrected with eyeglasses or contact lenses.
Prevention
Regular eye exams remain the key to early detection. If you are 65 years or above, plan and have regular eye check ups.
You can take the following steps to help slow or prevent the development of cataracts:
- Avoid or quit smoking as smoking produces free radicals, increasing your risk of cataracts.
- Ultraviolet light may contribute to the development of cataract. Therefore, wear sunglasses that block ultraviolet B (UVB) rays when you are outdoors.
- If you have diabetes or other medical conditions, you may take other preventive steps such as keeping diabetes under control, wearing UVB-blocking sunglasses when outdoors.
- Use eyeglasses or contact lens that are the most accurate to correct your vision defect.
- Use a magnifying glass to read.
- Improve the lighting in your home with more or brighter lamps.
- Wear sunglasses to reduce glare while going outdoors.
- Avoid night driving if possible.
