A cloudy change or opacification of the clear/ transparent lens of the eye.

What is a Lens? :

 Lens is an internal part of the eye (human or animal).
According to its natural shape and quality, LENS helps in forming an image on the retina, which is then interpreted by the brain.

The natural quality of the LENS is to be clear and convex in shape to allow the light to pass through and help in forming the images of the objects seen.

Losing the clarity (transparency) due to various reasons by the LENS is termed CATARACT.

The breaking down or changes in the anatomic constituents of the Lens causes it to become cloudy or Opaque at times.

Symptoms of CATARACT:

1. Having a cloudy or blurred vision.
2. Unable to perceive light or colors as intended to be.
3. A natural dullness of vision, especially during nights or in dim light.
4. Becoming extra sensitive to light .
5. Breaking or disintegration of light directly focused on roads or during
6. A gradual loss of the extent of vision.

Causes of CATARACT:

1. AGE:

The most common type of cataract is the age related or Senile cataract, seen generally in patients above 40 years of age. A natural change in the composition of the clear lens, gradually transforming it into an almost opaque state with various stages in between. The clear composition of the lens due to breakdown of its constituents causes it to lose it’s natural transparancy.

2. Medical Causes: Diseases like Diabetes, Usage of drugs like corticosteroids, exposure to radiation etc can cause Cataracts to form.

3. Previous injury to the Eye, certain chronic Eye diseases like Uveitis, Glaucoma, or Retinal disorders and their treatments can all lead to Cataract formation.

4. A genetic predisposition to early and certain types of cataracts can be seen in some families.

5. Ingestion of some chemicals and smoking may also cause cataracts. An age-related cataract generally progresses much slower than compared to other types seen in younger patients or cataracts caused due to other reasons.


When a person experiences any of the above symptoms, it is advised to visit an ophthalmologist for a proper diagnosis. There are different types of cataracts depending on the cause, structural or anatomical position of the cataract in the lens. An Ophthalmologist determines the type and stage of the cataract and determines the next step.


The definitive treatment for a Cataract is a surgical procedure, where the natural lens is replaced with an IOL( Intra Ocular Lens), an artificial lens that is compatible with the human body and stays there for the rest of the life.

Is Surgery always needed: When the surgery needs to be determined, by the Ophthalmologist depending on the patient’s condition, his visual impairment and the stage of the cataract, patient’s other health conditions etc.

In cases where there is no progress of the cataract and the vision is acceptable, surgery can be deferred until it effects the person’s quality of life.

Cataract Surgery Types:

There are more than one type of cataract surgery like,
Phacoemulsification is the most commomly employed procedure, which is a short 5 to 20 minute procedure, done as a day care procedure. It can be done under Topical or Local anaesthesia. There are different types of Lens used and that can be discussed under a different blog.