A cataract is a clouding of the natural lens inside the eye, which is normally clear. This clouding occurs when proteins in the lens break down and clump together, causing the lens to become cloudy or opaque. As a result, light cannot pass through the lens properly to reach the retina, leading to blurry, hazy, or less colorful vision
. Cataracts typically develop slowly and are most commonly related to aging, but they can also be caused by trauma, radiation, certain medical conditions, medications, or congenital factors. They can affect one or both eyes but do not spread from one eye to the other
. Symptoms of cataracts include:
- Blurred or cloudy vision
- Difficulty seeing at night
- Seeing halos or glare around lights
- Faded colors
- Trouble with bright lights
- Difficulty reading or recognizing faces
There are several types of cataracts:
- Nuclear cataracts: form in the center of the lens and may initially improve reading vision but eventually cause yellowing and worsening vision.
- Cortical cataracts: start at the edges of the lens and spread inward, causing glare and hazy vision.
- Posterior subcapsular cataracts: form at the back of the lens and often affect reading vision and cause glare in bright light.
- Congenital cataracts: present at birth or develop in childhood, sometimes due to genetic or prenatal factors
Cataracts are a leading cause of blindness worldwide but can be effectively treated with surgery. Cataract surgery involves removing the cloudy lens and replacing it with a clear artificial lens, which typically restores vision
