Dr. Niteen Dedhia

March 10, 2018

March 10, 2018

The opacification of the normal transparent lens is called cataract. The Latin word “Cataracta” means Waterfall – imagine trying to see through a sheet of falling water or through a frosted or fogged up window.

History

Eye with Normal Lens

Eye with Cataract

The earliest surgical treatment for cataract began in India and was called couching. In this procedure the sclera is incised and the lens is dislocated backward into the vitreous and displaced out of the optical axis. This procedure was performed for more than 2000 years until mid-eighteenth century. Great progress in cataract surgery has been made in recent years with the introduction of microsurgical instruments, microscope & modern surgical techniques like phacoemulsification

Lens: The lens consists of the

Capsule

Cortex

Nucleus

The primary function of the lens is to focus light on the retina, while remaining transparent. This transparency depends on maintenance of structural (anatomic) & functional (physiologic) integrity of its cells.

The lens is 66% water, the least hydrated organ of the body, the remaining bulk is composed mainly of protein. It is devoid of any blood supply and derives its nourishment from the surrounding fluid of the eye i.e. aqueous & vitreous.

Age related or senile : Occurs as a result of natural ageing process of lens fibers, which become opaque over a period of time.

: Occurs as a result of natural ageing process of lens fibers, which become opaque over a period of time. Traumatic Cataract: Develops as a result of injury to the eye.

Develops as a result of injury to the eye. Metabolic Cataract: Develops as a result of defect in body metabolism – Diabetes- Calcium disorders.

Develops as a result of defect in body metabolism – Diabetes- Calcium disorders. Toxic Cataract: Certain Toxic Substances or Drugs can lead to cataract if taken for a long time due to any reason. Eg. Steroids Miotics, Chlorpromazine, etc.

Certain Toxic Substances or Drugs can lead to if taken for a long time due to any reason. Eg. Steroids Miotics, Chlorpromazine, etc. Secondary Cataract: develops as a result of some other primary eye disease such as chronic inflammation or glaucoma.

Normal Eye

It varies from person to person but as a general rule, most cataracts develop slowly over a period of time. A cataract can take months or even years to reach a point where is adversely affects vision.

One may not be aware that a cataract is developing if the size and location of the cloudy areas in the lens are not in the Central pupillary area. As the cataract progresses, there is deterioration of distance and reading vision. One may experience hazy and blurred vision. Double vision may also occur when a cataract is beginning to form.

Eye with Cataract

The eye may also be more sensitive to light and glare, making night driving difficult. There may be a need to change the glass prescription in the early stages which may help temporally. As the Cataract develops, stronger glasses would no longer improve the vision. This can lead to imbalance between the two eyes, which may cause headache. One may also experience Poor night vision, poor depth perception e.g. difficulty in getting downstairs.