If you’ve been diagnosed with a cataract, you’re not alone. Millions of people around the world undergo cataract surgery each year. Cataracts grow quite slowly, so the time between diagnosis and surgery may be several years.
But wherever you are in your cataract journey, knowledge about the eye and how it functions is helpful in understanding how your eye doctor will evaluate your unique situation, and recommend a replacement lens.
Today, let’s look at the shape of the cornea.
How does the shape of the cornea affect my vision?
Normally shaped like a dome, the cornea, the clear outermost part of the eye, acts like a window in that it controls and focuses the light that enters it. But not all corneas are perfectly dome-shaped. In fact, corneas come in many shapes and sizes. Some corneas are shaped more like an American football.
When the cornea is not symmetrical, it can’t properly refract, or bend, the light as it passes through it. When the cornea is sloped more in one area than another, it is more complex and it can cause objects near or far to appear blurry or distorted. So, the cornea is a major influencer on vision.
What can affect the shape of my cornea?
There are many reasons a cornea can be considered complex. These include:
- Genetics
- Corneal surgery, such as LASIK or radial keratotomy (RK), particularly if the surgery was performed more than two decades ago using older technologies
- Certain eye conditions, such as keratoconus, can causes the cornea to thin out and then gradually bulge outward
- Injury or trauma to the eye
Complex corneas and cataract surgery
If you have a history of laser surgery, eye trauma or certain eye conditions, it may affect how your doctor approaches your cataract surgery. Cataract surgery involves replacing the cloudy natural lens of the eye with an artificial lens, known as an intraocular lens. If the light entering the lens of the eye is influenced by the shape or complexity of your cornea, your eye doctor will consider this as one factor in helping you to achieve the best possible outcome from cataract surgery.
Each patient is unique, and the shape of the cornea is only one element of consideration when planning for cataract surgery. But by understanding more about how your eye works, you can better discuss the process with your eye doctor.
References and more information:
https://www.nei.nih.gov/learn-about-eye-health/eye-conditions-and-diseases/corneal-conditions
