WHAT IS CATARACT?

Opacification of the normally transparent crystalline lens is called as cataract. Normally the light rays pass through the lens and get focussed on the light sensitive layer of the eye (Retina). To produce a sharp image, the lens has to be clear and transparent. Lens is made up of water and protein arranged in such a way that light passes through it. If this arrangement is disturbed, it leads to the development of cataract. It can be congenital or can occur due to aging, injury, drugs and other diseases of eye like Iritis (Inflammation of the Iris), Glaucoma (Increased Intraocular Pressure).

This is the most common type of cataract. This is due to aging changes in the lens in patients above 40 years of age. The exact age at which the cataract starts to develop varies with individuals. It can be nuclear or cortical or capsular type of cataract.

Traumatic Cataract:

Injury to the eye either penetrating or blunt can lead to the development of cataract. After injury, the cataract can occur immediately or after a few days.

Congenital Cataract:

Babies can be born with cataract due to malnutrition of the mother or some infections of the mother (For example:Toxoplasmosis ( a parasitic infection) , Cytomegalovirus (a viral infection), Rubella ( a viral infection)). This condition should be diagnosed early and should be operated at the earliest age or otherwise it would lead on to permanent blindness.

Complicated Cataract:

Due to Diseases of the other parts of Eye example:- Iritis, Glaucoma, Choroiditis,(Inflammation of choroid, the middle vascular layer of eye ball) Retinal detachment (detachment of retina from its attachment, a serious condition producing severe visual loss).Patients with history of recurrent pain, redness of eyes and blurred vision could be suffering from complicated cataract. As these predominantly affect visual axis, this gives rise to early loss of vision.

Toxic Cataract:

These types of cataracts are produced by ingestion of Drugs or other toxic compounds.

Corticosteroids (given for allergy and asthma and many other conditions) taken for long periods can lead to development of cataract

Other drugs like Amiodarone,(given for heart problems) Gold compounds (given for rheumatoid arthritis)can also produce cataract.

Metabolic Cataract:

Diseases like Diabetes mellitus, Galactosemia can lead to the development of cataract.