Different Types of Cataracts

1. Age Related Cataract

  • Nuclear Sclerosis:

This is a hard cataract. The lens becomes hard and yellow as it ages. This usually progresses slowly over time. This type of cataract causes greater impairment of distance vision than near vision. In the early stages, the hardening of the lens causes the refractive power to change causing the lens to become myopic or nearsighted.. In some cases patients are able to read without their eyeglasses, this condition is called “second sight”.

  • Cortical:

This is a peripheral cataract. The cloudiness is located near the outer edges of the lens. The effect on vision varies depending on the location of the cloudiness on the lens. A common symptom is glare from light sources such as headlights of oncoming cars. Cortical cataracts vary greatly in their rate of progression.

  • Posterior Subcapsular:

This cloudiness begins at the very back layer of the lens. This usually occurs in younger patients. The common symptoms are glare and poor vision in brightly lit conditions. Near vision tends to reduce more than distance vision. In addition to being one of the main types of age-related cataracts, posterior subcapsular cataracts can occur as a result of trauma, corticosteroid use and exposure to radiation.

2. Congential Cataract

These are present at birth. This type of cataract occurs in 1 out of 2000 births. These cataracts may not affect vision. If they do, they may need to be removed. The main reasons these occur are usually the child has an associated syndrome with this, may be inherited and one third are due to undetermined causes.

3. Secondary Cataract

When doing cataract surgery the surgeon removes the inner portions of the lens. The outside layer of the lens, called the capsule is left in place to hold the artificial implanted lens. This outer layer can become cloudy and cause visual disturbance. This secondary clouding is called a secondary cataract. The onset of a secondary cataract can occur within months or years after cataract surgery. It usually occurs in both eyes. This type of cataract is easily treated by laser.

4. Traumatic Cataract

This type of cataract is a result of either an injury by physical force, radiation, electrical current, chemicals or disease such as diabetes. These may become present right after the injury or years later.