What is a Cataract?

11:25 AM

Cataract extraction is one of the most commonly performed surgeries in the United States, but based on my experience in patient care, a large percentage of people are unsure of what a cataract actually is. To explore this topic further, let’s address some common misconceptions:

1) Cataracts are NOT a film over the surface of your eye.  This is a very common misconception, but cataracts actually develop inside your eye in a structure called the lens (see picture below).  The lens functions just like a lens on a camera – it changes shape to focus and create a clear image.  Over time this lens can harden and become cloudy, which is the development of a cataract.  Just as you would expect, clouding and yellowing of the structure responsible for focusing a clear image results in constant blurry vision. 
This picture shows a cross-section of your eye, diagramming the lens which has developed a cataract in this case.  The lens is located INSIDE the eye, sitting behind the iris (or the colored part of the eye).  Picture courtesy seewithlasik

2) Cataracts are NOT a disease.   Most often they are a result of the normal aging process the lens.   While aging is the predominant factor for developing cataracts, certain medical conditions like diabetes can predispose someone to developing cataracts sooner than usual.  Prolonged use of steroids can also cause cataract formation.  It is also possible to born with cataracts which can cause substantial deficiencies in the development on the visual system, so having a comprehensive eye exam is important even for children!
This patient has a nuclear cataract, characterized by yellowing of the lens.   This is one of the most common types of cataracts caused by aging, smoking, and UV damage.  Picture courtesy drhlis.com

3) I know it is a scary concept to some, but the ophthalmologist performing your cataract surgery will have to enter the eye to remove it.  Remember that the lens where the cataract forms is inside of your eye, behind the iris (the colored part of your eye).  The surgeon uses very small instruments to enter the eye and remove the cataractous lens.  With today’s technical advancements, you don't even have to be put to sleep to have this procedure performed.

4) Once a cataract is removed it can NOT grow back.  That’s a relief, right?  It is possible that a film can grow over the back of the intraocular implant (a small device that surgeons insert to replace your lens to allow you to focus a clear image again).  This film may reduce vision, but you will not have to have a second surgery to remove it.  All it takes is a quick laser procedure.  

5) Most people DO still need to wear glasses after cataract surgery.  While in most cases the goal of surgery is to fully correct your distance vision, the standard intraocular implant inserted to replace your lens is not able to focus for near distances.  That means that you will continue to need reading glasses.  Depending on your eyes and the surgical outcome, some people may also have left-over astigmatism (which causes blur at all distances) that must be corrected with glasses.  There are more expensive intraocular lens devices available that can help focus for both distance and near, but the technology has not been entirely perfected at this time.  Researchers are actively exploring this idea though, so expect future breakthroughs.

6) There is NOTHING you can do to entirely prevent yourself from getting cataracts.  Yes, that is 100% a true statement.  To use the words of a fellow optometrist, “ everyone will get cataracts if they live long enough.”  Some people get them younger; some people’s progress more rapidly to reduce vision; some people will never have the cataract bother them enough to want surgery.  There ARE some things you can do to slow down the onset and progression of your cataracts, however.  Some suggestions:
 A) DO wear sunglasses outside.  UV light can damage the lens and lead to cataract formation.  Studies show that more Americans are applying sunscreen because of the risk UV damage to the skin, but much fewer people responded to wearing sunglasses for UV protection.  Your eyes need protection too, and there are a lot of stylish options out there!
Wearing sunglasses is not just a fashion statement , but protects your ocular health and vision.  Choose 100% UVA/UVB blocking sunglasses for maximum protection.  Plus, there are so many stylish options out there like Gucci 3164 in tortoise above!
B)  DON’T smoke.  Like you needed any more reasons.  Smoking increases the rate and progression of cataracts.

C) DO have yearly eye exams.  Tell your doctor about medical conditions like diabetes, Wilson’s disease, and myotonic dystrophy that predispose you to cataracts.  Be aware that certain medications (especially steroids) also increase your risk.  If you are having blurry vision, it is always best to get it checked out.  Cataract surgery is a relatively easy procedure, but in conditions like diabetes, having the cataracts removed earlier may help decrease the surgical risk and improve the outcome of your vision!  You don’t want to wait until your vision is drastically impaired.

D) If you are a parent, your children DO need to have their eyes checked as well! Some children are born with vision-threatening conditions like cataracts, and the earlier these problems are caught, the better chance your child has for developing normal vision.  Because a child's eyes and visual pathway to the brain are still developing, a cataract in a child can cause permanent vision loss, even after the cataract is removed! Programs like InfantSEE allow free eye exams for children between 6 months and 1 year of age.  This is a great way to screen for blinding conditions, so please seek out local providers to see if they are participants! 
This child's parents are truly protecting them from dangerous UV damage by using a brimmed hat and sunglasses!  You can purchase sunglasses for children and babies through companies like Baby Banz

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  1. Cataract is one eye condition in which people can't see properly and vision become cloudy. It need emergency treatment otherwise it can be resulted in very big problem.

    what are cataracts