One of the ironies about cataract symptoms is that they develop so slowly – over years, in most cases – and they can be hard to detect. The time when most people learn just how much their cataracts had affected their vision is after surgery, when yellowed tones become white again and what looked like muted colors or blurry details return to their true clarity.
A quick tour of the eye
When you look in the mirror, you see the round black centers of your pupils, the color of your irises and the whites of your eyes. The cornea is the transparent, gel-like tissue across the front of your eyes. And what can’t be seen without special tools is the lens of the eye, which is made mostly of protein and water and is located just behind the pupil and iris. The lens helps focus light on the retina, which sends images to the brain to be “seen.”
That lens is ordinarily clear. But if the protein in the lens starts to clump together, a cataract begins to form and that lens begins to turn cloudy. This worsens over time, which means images lose sharpness and colors lose their intensity. A sky that would look light blue to a normal eye may seem brownish or overcast to a person with severe cataracts.
What are the noticeable symptoms of cataracts?
A person who has developed cataracts in one or both eyes may experience some or all of the following visual symptoms:
- Difficulty with night vision, especially while driving
- Blurry or cloudy images
- Seeing colors in muted shades, or with a yellowish or brown cast
- Sensitivity to glare, or halos that surround lights at night
- Double vision (in one or both eyes)
- Frequent prescription changes
Who gets cataracts?
Most people are familiar with age-related cataracts, typically affecting people over age 60. The American Academy of Ophthalmology estimates that normal cataracts today affect more than 24.4 million Americans age 40 and older, and that by age 75, half of all Americans have them. They are the most common cause of blindness in the world, per Prevent Blindness America. However, there are other forms of cataracts, including:
- Congenital cataracts: These cataracts are present at birth or form before age 1, and often occur with other birth defects. Mild cases may not affect vision, while moderate to severe cataracts are corrected with the same type of surgery performed on adults.
- Radiation cataracts: These can be caused by exposure to certain amounts and kinds of radiation. Cataracts caused by high levels of exposure may take only a year or two to develop, while those caused by lower doses may take many years.
- Secondary cataracts: Secondary cataracts are slightly misnamed. They occur in patients who have had their cataracts removed. A new lens is inserted when the cloudy lens is removed (see surgical section below), but the back part of the lens capsule stays in the eye and can become cloudy on its own, months or years later. The percentage of people who get secondary cataracts is small.
- Traumatic cataracts: An eye that is injured through acute trauma can sustain many kinds of damage, including an induced cataract, over the ensuing weeks, months and years.
There are also names for cataracts depending on what part of your eye they affect:
- Nuclear cataracts: Those that affect the center of your eye’s lens and typically develop more of a yellow or brown hue.
- Cortical cataracts: Those that affect the edges of your lens and later move toward the center.
- Posterior sub-capsular cataracts: Those that affect the back of your lens. They can progress faster than other cataracts, and can affect your night vision and your need for light while reading.
What causes cataracts to develop?
While no single, definitive cause of cataracts has been determined, researchers have associated many factors with their occurrence. They include:
- Ultra-violet radiation (UV): Primarily from being in the sun too much without protection
- Severe nearsightedness: A condition also known as high myopia
- Genetic links: Traits often identified in family history
- Lifestyle factors: Obesity, smoking and high alcohol consumption
- Co-morbid conditions: Diabetes and high blood pressure
- HRT: Hormone replacement therapy
- Long-term or overuse of prescribed drugs: Corticosteroid or statin medicines
- Eye injuries: Previous eye surgery, injuries or ailments to the eyes
How are cataracts treated?
Most doctors recommend having cataract surgery once the changes in your vision begin to affect your ability to perform your normal daily activities.
Once you’ve made the decision to undergo the procedure, you will be scheduled for outpatient eye surgery by your doctor. On the day of the surgery, you’ll be given Valium or a similar medicine to help you relax.
Your surgeon will numb your eye with anesthetic eye drops, dilate your pupil with more drops, and then make a tiny incision in your cornea through which your cloudy lens is removed and a clear artificial lens – called an intraocular lens – is inserted in its place. That lens will remain permanently in your eye. In appropriate cases, the inserted lens can be made to your prescription, which ends the need for corrective eyeglasses or contact lenses post-surgery.
The surgery itself takes only minutes, though prep and aftercare mean you’ll be at the facility for two to three hours. Typically, your eye has a protective shield over it when you are released, which remains in place for a few hours. You’ll be given antibiotic drops to prevent infection and will be advised to use artificial tears to relieve any scratchiness or irritation in the coming days. Patients tend to wear an eye guard at night while their eye heals to prevent accidentally rubbing the eye during sleep.
If you have cataracts in both eyes, which is common, your surgeon will do one eye at a time. Generally, the surgery on the second eye is scheduled once the first eye is completely healed, in about six to eight weeks.