Video – Eye Anatomy: The Cornea…and Contact Lenses, Degenerations and Keratoconus

Your eye is like a camera.  There are 2 structures that focus light – much like the lens of a camera.  These 2 structures are the cornea and the lens.  The cornea is the clear front surface of your eye that is located in front of the colored part of your eye (called the iris).

If you are a contact lens wearer – the contact lens sits on the cornea.  Not all corneas are the same size.  Some are more curved or “steep” and others are more “flat”.  It is important to be properly fit for contact lenses by your eye doctor.  If a contact lens is not properly fit, the contact can cause serious problems for the wearer – including corneal distortion, corneal swelling, corneal ulcers, inflammation and more.

A corneal topographer is an instument that can detect any corneal distortions caused from a contact lens.  A contact lens may look and feel “fine” but, it can still be causing problems that you may be unaware of.  Many times sleeping in your contact lenses or overwearing your contacts (wearing a 2 week contact for more than 2 weeks) can cause corneal distortions.

Cornea With Keratoconus

At Visionary Eyecare in Pembroke Pines, Sunrise and Davie- we perform a corneal topography on ALL contact lens patients. During the contact lens eye exam we use the corneal topographer to monitor the health of the patient’s cornea before fitting with a new contact lens and also to monitor the corneal health year to year for established contact lens wearers.

Corneal Topography can also detect some corneal degenerations and corneal dystrophies like keratoconus.  Typically a person with keratoconus has a lot of astigmatistm, distorted vision and possibly sensitivity to light.  The cornea starts to protrude in a “cone-like” fashion.  Most of the time a specialty contact lens can help these patients see clearer and may prevent the corneal dystrophy progression.  In advanced cases, the apex of the cornea may thin so drastically from keratoconus that a corneal transplant may be necessary.

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Video – What is Astigmatism? A Video Description of Astigmatism

Astigmatism is a refractive error –  meaning that the light that is coming into the eye is not focused perfectly on the “film” in back of the eye (called the retina – which is a layer of nerve tissue).  The retina is much like a movie screen or the film in your camera – the image must be focused PERFECTLY on the retina for the eye to see clearly.  If the image is focused in front of the retina or behind the retina – much like a movie screen or camera film – the image will be blurry.  This unfocused image is sent by the retina to the brain – where it is perceived as blurry, cloudy or distorted vision.

Astigmatism is a refractive error caused when the front surface of the eye (the cornea) or the lens (which is located inside the eye behind the colored part of the eye – called the iris) is irregularly shaped and oblong – much like a football.  This irregular shape causes the light to be focused on 2 seperate points – either in front of or behind the retina.  This causes distortion of the vision and blur at all distances.  So objects at a distance and also nearby are blurry and/or distorted.  The higher the degree of astigmatism – the more distortion and blur you will have.

Several methods can focus the light perfectly on the retina for you.  Glasses, contact lenses (called astigmatic or toric contacts) or laser vision correction are aids that are available to help focus the light and images on the retina – which will get you to see clearly again!

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Video – What Is Astigmatism? What Causes Astigmatism?

Video - What Causes Astigmatism?

Click the video above to learn what is the cause of Astigmatism. It is most commonly caused when the shape of front surface of your eye (called the cornea) is not perfectly round (like a baseball)  but, it is more oblong shaped (like a football).  When this oblong shape is located on the cornea then it is called “Corneal Astigmatism”.  Less often, the lens inside your eye (located right behind the colored part of your eye called the iris) can also be oblong shaped.  This is called “Lenticular Astigmatism”.

Most commonly, people are born with this oblong shape to their eyes and often it can become a bit worse as time goes on.  More rarely – astigmatism can be induced by a trauma to the eye.

Astigmatism causes a blur and distortion to your vision – for both distance and near objects.  The higher the amount of astigmatism – the worse the blur and distortion will be. Astigmatism can be corrected with a variety of options – glasses, contact lenses (called toric or astigmatic contacts) and laser vision surgery.

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Diagram of Your Eye

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PLACE YOUR MOUSE OVER THE MAGNIFYING GLASS

AND USE IT TO MOVE THE MAGIFIER OVER

EACH PART OF THE EYE

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Online Eye Test For Astigmatism

Astigmatism is a visual condition caused when some surfaces of the eye are oval shaped….like a football or an egg.  These surfaces in the eye that are oval shaped can be the cornea (the front of the eye) or the lens (inside the eye). Most often astigmatism is caused by the cornea being oblong or oval shaped.

This oblong shape causes the light rays that enter the eye to be distorted and not focus properly on the retina in the back of the eye.  If you have uncorrected astigmatism, you can have various symptoms such as blurry vision, eyestrain, tired eyes, headaches or fatigue.

Here are several links to websites that have online testing for astigmatism. Check them out!!

CLICK HERE for ONLINE ASTIGMATISM TEST #1

CLICK HERE for ONLINE ASTIGMATISM TEST #2

CLICK HERE for ONLINE ASTIGMATISM TEST #3

CLICK HERE for ONLINE ASTIGMATISM TEST #4

Astigmatism can be quickly and easily corrected with eyeglasses, contact lenses (called astigmatic or toric contacts) or Laser Surgery (called Lasik).

If you feel that you may have astigmatism and you need correction OR if has been more than 12 months since you have seen an eye doctor…..its time for you to schedule an eye exam!

Astigmatism Diagram courtesy of:

Click on the WebMD Logo above

to check out more information on Eye Health!

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