What are cataracts?
Cataracts are cloudy areas that form on the lens of your eye. Your lens is a clear, flexible structure made mostly of proteins (crystallins). As you get older, the proteins in your lens break down, forming cloudy patches that affect your vision.
You may feel as if you’re looking at the world through a dirty window. Over time, your vision gets worse. You may have a hard time carrying out routine tasks.
Healthcare providers consider cataracts an inevitable part of aging, and age-related cataracts is the most common form of the condition.
But you don’t have to live with fading vision. Ophthalmologists can do surgery to remove the cataracts and restore your vision.
Types of cataracts
There are many types of cataracts. This article focuses on age-related cataracts. Other cataract types include:
- Pediatric cataracts. Pediatric cataracts affect babies and children. Babies may be born with cataracts (congenital), or the cataracts may form sometime after birth. Pediatric cataracts typically run in families, but they can also happen due to eye injuries or other eye conditions. Babies and children with pediatric cataracts need prompt treatment to prevent problems like amblyopia (lazy eye).
- Traumatic cataracts. These cataracts form when something injures your eye. Treatment for this type is more complicated because structures around the lens may also need repair.
- Secondary cataracts. These are cloudy patches that form on your lens capsule, or the membrane that covers your lens. Another term for this condition is posterior capsular opacification. It’s a common but easily treatable complication of cataract surgery.
Types of age-related cataracts
There are several types of age-related cataracts. Their names refer to their location in your lens. To understand these types, it helps to learn a bit about the anatomy of your lens.
Your lens is made up of a few layers. You can think of them like the layers of an apple:
- The nucleus is in the center of your lens. It’s like the core of the apple.
- The cortex is the layer that surrounds the nucleus. It’s like the fruit you eat that surrounds the core.
- The lens capsule is the thin membrane covering the cortex. It’s technically not part of the lens itself, but is instead like a close-fitting skin that covers and protects the lens. The lens capsule is a bit like the apple skin.
Eye care providers classify cataracts based on where they form in your lens. Often, people have more than one type at the same time. That’s because it’s common for cloudy patches to form in multiple areas of your lens. The three most common types of age-related cataracts are:
- Nuclear sclerotic cataract, which forms in the nucleus.
- Cortical cataract, which forms in the cortex.
- Posterior subcapsular cataract, which forms in the posterior cortex. “Posterior” in this context means the “back” of your lens. This is the part that’s closest to your retina (which is behind your lens). “Subcapsular” means the cataract forms at the outer edge of the cortex, just beneath the lens capsule.
At what age do cataracts usually start?
The proteins in your eye’s lens start to break down around age 40. But you typically won’t notice symptoms until age 60 or later. Certain medical conditions, like diabetes, may cause you to have symptoms sooner.
How common are cataracts?
Cataracts are very common in the U.S. and globally. According to the World Health Organization, about 17% of people around the world have cataracts that cause problems with their vision. However, the prevalence varies widely by country and region. There’s a higher prevalence in middle-income and low-income nations where people often have more risk factors and limited access to cataract treatment.
In the U.S., nearly 1 in 5 people age 65 to 74 have cataracts that affect their vision. More than 50% of people over age 80 either have cataracts or had surgery to remove them.
Symptoms and Causes
What are the symptoms of cataracts?
Cataract symptoms include:
- Vision that’s cloudy, blurry, foggy or filmy.
- Changes in the way you see color (colors may look faded or not as vivid).
- Sensitivity to bright sunlight, headlights or lamps.
- Glare, including halos or streaks that form around lights.
- Difficulty seeing at night.
- Changes in your vision prescription, including near-sightedness that gets worse.
- Needing a brighter light to read.
- Double vision.
Are cataracts painful?
Cataracts don’t usually hurt. But they can cause discomfort by making your eyes more sensitive to light.
What causes cataracts?
The main cause of cataracts is the gradual breakdown of proteins in your lens.
However, certain genetic and environmental factors can raise your risk of developing cataracts or developing them at a younger age compared with others.
What are the risk factors for cataracts?
Risk factors for cataract formation fall into three main groups: environmental, medical and genetic.
Environmental risk factors
Environmental risk factors are those that you encounter in the world around you. They’re sometimes toxic substances that you breathe in or ingest. Environmental factors are harmful because they increase the amount of free radicals in your body. These are unstable molecules that damage healthy cells. Free radicals, by harming the cells in your eye’s lens, can lead to cataract formation.
Environmental risk factors include:
- Air pollution.
- Tobacco smoke.
- Industrial chemicals.
- Long-term exposure to UV light from the sun.
- History of radiation therapy to the upper part of your body.
Limiting your environmental exposures may slow down cataract formation. Researchers continue to look into the exact role that preventive measures play.
Medical risk factors
Medical risk factors can that raise your risk for cataracts include:
- Having diabetes or high blood sugar.
- Having certain eye surgeries, like glaucoma.
- Using corticosteroids to treat some medical conditions (like rheumatoid arthritis).
- Having certain eye diseases, like retina pigmentosa or uveitis.
Genetic risk factors
A family history of cataracts raises your risk of developing them. Some genetic mutations lead to congenital cataracts (present at birth). When it comes to age-related cataracts, genetic mutations may make your lens more vulnerable to damage from environmental risk factors. Researchers continue to explore these connections.
So, while you can’t change your genetic risk, it helps to know your family history and share it with your provider.
Diagnosis and Tests
How are cataracts diagnosed?
Ophthalmologists and optometrists diagnose cataracts through a comprehensive eye exam. Your provider will closely examine your eyes to look for signs of cataracts and assess their severity. Your provider will also ask you about your vision, your medical history and if you’re having trouble with everyday tasks because you can’t see as well as you once did.
Tests to diagnose cataracts
Specific tests you may have include:
Management and Treatment
What is the best way to treat cataracts?
Cataract surgery is the only way to remove cataracts and restore your clear vision. During cataract surgery, an ophthalmologist removes your clouded natural lens and replaces it with an intraocular lens (IOL). An IOL is an artificial lens that permanently stays in your eye. There are many different options for IOLs that your provider can discuss with you.
The main benefit of an IOL is that it’s clear — like your natural lens should be. Another benefit is that it can correct refractive errors, allowing you to rely less on glasses or contact lenses after your surgery.
Is cataract surgery safe?
Cataract surgery is one of the safest and most commonly performed surgeries in the U.S. Most people have no serious complications. But it’s important to be aware of all possible risks, including retinal detachment and infection.
Certain eye diseases or underlying medical conditions can raise your risk of complications. So, you should talk to your provider about your individual level of risk prior to your surgery. Also, ask how they can treat any potential problems that may occur.
Recovery from cataract surgery
You may have mild pain and discomfort after your surgery. Your provider can give you a pain reliever to use for the first day or two.
Full recovery takes four to eight weeks. But you should notice improvements in your vision much sooner. Your provider will tell you when it’s safe to return to your usual activities.
Can I prevent cataracts?
Developing cataracts is a typical part of aging. However, you can take a few steps to protect your eye health and potentially slow the process:
- Don’t smoke. Tobacco smoke raises your risk of cataracts. If you currently smoke, ask a healthcare provider for resources to help you quit.
- Protect your eyes from the sun. Wear sunglasses or eyeglasses with an anti-UV coating. A hat with a brim can also help.
- Get regular eye care. Ask your provider how often you should come in for checkups. Be sure to keep up with your appointments and tell your provider about any new or changing symptoms.
Outlook / Prognosis
What can I expect if I have cataracts?
An ophthalmologist or optometrist is the best person to ask about your outlook. They’ll examine your eyes and the severity of any cataracts you have.
Early on, you might not need surgery. The changes to your vision may be mild. But cataracts can progress over time, causing more noticeable symptoms. If your symptoms start to interfere with your daily life, your provider may recommend surgery to help you safely go about your usual tasks.
How can I take care of myself?
There’s a lot you can do to take care of yourself if you have cataracts. Tips include:
- Wearing polarized sunglasses to reduce glare in strong sunlight.
- Using a magnifying glass to help you read.
- Adding brighter lightbulbs to your lamps to help you see better when reading.
- Trying to avoid driving at night if the headlights bother you or cause glare.
- Seeing your eye care provider according to the schedule they provide and updating your eyeglasses prescription as needed.
- Managing any underlying medical conditions, like diabetes.
When should I see my healthcare provider?
Contact your provider if you have symptoms of cataracts or if you notice any changes in your vision. Issues like blurred vision can signal many potential eye problems, aside from cataracts. So, it’s important to see a provider and learn the cause of your symptoms so you can receive appropriate treatment.
When should I go to the ER?
Seek emergency care immediately if you have symptoms of a retinal detachment. This is a rare but serious complication of cataract surgery that affects about 1 in 100 people. Warning signs include:
- Sudden onset of floaters and flashes.
- Flashes of light you notice with your eyes open or closed.
- A shadow or curtain spreading across your line of sight.
What questions should I ask my eye care provider?
Some questions you may want to ask your provider include:
- Do I have signs of cataracts?
- How severe are the cataracts?
- What type are they and where are they located in my lens?
- Are both of my eyes affected?
- When do you think I might need surgery?
- What are the risks of surgery for me?
- What type of IOL would be best for me?
- What can I do to see better until I have surgery?
- What lifestyle changes should I make?
A note from Cleveland Clinic
Cataracts are a common part of aging, but that doesn’t make a diagnosis any more pleasant to hear. The prospect of eye surgery might make you feel nervous, and you might wonder what your vision will be like afterward.
Try not to worry too much. Remember that cataract surgery is one of the most common and routine procedures in the U.S. Chances are, you know at least one person who’s had the surgery and can serve as a resource for you. Talk to them and ask about their experiences. But don’t feel pressured or rushed to schedule surgery. Work with your provider to decide the right timing for you.
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