A cataract is a loss of transparency, or clouding, of the normally clear lens of the eye. This lens is a part of the eye that helps focus light on the retina. It is located behind the iris. The term cataract is derived from the Greek word cataracts, which describes rapidly running water.
When water is turbulent, it is transformed from a clear medium to white and cloudy. Cataract development is usually a very gradual process of normal aging but can occasionally occur rapidly. Many people are in fact unaware that they have cataract because the changes in their vision have been so gradual.
Cataract commonly affects both eyes, but it is not uncommon for cataract in one eye to advance more rapidly. Some children develop cataract, called congenital cataract, before or just after birth; these are usually dealt with differently from cataract in adults.
What causes Cataract?
Age-related or senile:
This is the most common cause & it occurs as a result of the natural aging process of the lens fibers which become opaque over a period of time.
Develops as a result of injury to the eye, Traumatic cataracts occur secondary to blunt or penetrating ocular trauma. Infrared energy, electric shock, and ionizing radiation are other rare causes of traumatic cataracts.
Occurs as a result of defect in body metabolism like diabetes
Infection or Inflammation in the eye
Certain medication can lead to cataract if taken for a prolonged period e.g. steroids
Rarely some children are born with cataract
If there is a strong family history, cataract can occur very early in life, even as early as 20 years
Develops as a result of other primary eye diseases such as glaucoma or chronic inflammation
Symptoms of cataract:
• An early sign is increasing glare from strong sunlight or, bright at night making driving difficult.
• There may be hazy or blurred vision making it difficult to read small print or perform fine tasks.
• Double vision or distortion of images may occur.
• Things may seem brighter in one eye than the other.
• There may be a need to change glasses frequently.
• There may be poor depth prescription e.g. difficulty in getting downstairs.
When should one be operated upon for cataract?
When a cataract causes enough loss of sight to interfere with the patient’s routine lifestyle, it is time to remove it. One should not wait for the cataract to ‘ripe’ or mature. The less mature the cataract the easier the surgery and faster the recovery.
Treatment of Cataract:
This involves removal of clouded lens and its replacement with a clear synthetic intraocular lens (IOL). Surgical removal is the only treatment for cataract. The decision to operate is taken jointly by the doctor and the patient.
There are two treatment options available.
1. ECCE – A conventional technique
– Requires an incision 10-12 mm
– Multiple stitches required
– Clouded lens is removed in one piece.
– A non-foldable lens is implanted.
– More chances of a high post-operative cylindrical number.
– This procedure is obsolete.
2. Micro-incision Cataract Surgery (Phacoemulsification Technique)
– A modern technique
– Incision 2mm to 3mm
– Stitchless operation
– Cataract lens is liquefied by ultrasound energy and sucked through the phaco emulsifier probe.
– Then an intraocular lens (IOL) is implanted in the eye permanently.
Advantages of Phaco
i. Faster healing
ii. Less trauma to the eye
iii. It is a stitchless operation and is done under local or topical (eye drops) anesthesia.
iv. Quicker resumption of normal activity.
v. Less chances of post-operative cylindrical lens
Advantages of intraocular lens (IOL)
i. It causes no magnification
ii. No distortion of object
Foldable intraocular lenses
These lenses are inserted through yet a smaller incision by folding. Foldable lenses are made of silicone acrylic. As their production involves high-quality technology, their cost is higher.
- Monofocal IOL : Provides clear vision for one distance
- Multifocal IOL: With these lenses dependency on glasses for near and distance vision is minimal.
- Aspheric IOL : Gives improved image and sharpness
- Toric IOL: Premium IOL that corrects astigmatism (cylindrical power).
- Trifocal: Latest generation of lenses. Allows an individual to see distance, intermediate and near. We may be able to eliminate spectacle wear.
How do I know when having a cataract?
The most common symptom is blurred vision. As the cataract develops, the progressive clouding can make night driving difficult by intensifying the reflection of lights. Symptoms differ from one person to the next. It depends on the type of cataract and how far it has progressed.
Can I have any other treatment for cataract?
Diet, medicine, eye drops or exercise have not been shown to retard or prevent the development of cataract. A cataract does not result from using the eyes too much, or by reading in bad light.
When should I operate?
Ideally, with modern methods, a cataract can be removed at any stage, but it should be operated when it interferes with your daily life.
Should I wait till the cataract advances or matures?
With the modern technique of Phaco, the cataract needs to be broken inside the eye. As the cataract advances, it hardens making it difficult to remove by Phaco. Over-matured cataract can burst in the eye and result in complete loss of vision. Thus Phaco surgery needs to be done while the cataract is still soft.
Which is a good technique for surgery?
Phacoemulsification is a good technique with the advantage of a micro incision, no stitches, safer and faster recovery.
Which is a good lens?
Foldable lenses are good as they can be inserted through micro incision requiring only a small puncture. With advanced optics foldable lenses, the quality of vision especially at night and low light conditions are much better.
What special treatment does my eye require while healing?
Use drops as directed. Wear protective sunglasses whenever you are outside on sunny days if the glare causes discomfort. Avoid direct pressure on the eye? don’t rub or scratch the eye.
What precautions are to be taken after surgery?
Avoid rubbing the eye or compression (while sleeping) for a month.
Avoid dust, pollution, and water entering the eyes for a month.
Head baths should be avoided for 15 days.
Follow the medication guideline strictly and maintain good eye hygiene.
Will I require glasses after surgery?
It depends on the eye and the healing responses of the body. Gross work can be done without glasses but fine work may require a visual aid.
When can I resume daily routine?
Daily routine work can be resumed after a rest of 2 days depending on the work environment. Dust, pollution and stressful conditions should be avoided.
What is After-cataract or Charri?
The natural lens covering thickens over time which causes blurred vision, known as? After Cataract or Charri?. This can be removed without surgery using a laser.