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How to treat Cataracts.

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Introduction

CATARACTS

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                 Normal Vision                                  Eye with Cataracts

A cataract is a clouding of the natural lens, the part of the eye responsible for focusing light and producing clear, sharp images. The lens is contained in a sealed bag or capsule. As old cells die they become trapped within the capsule. Over time, the cells accumulate causing the lens to cloud, making images look blurred or fuzzy.  The light rays are refracted off their normal path onto the back part of the eye making the objects appear out of focus.

TREATMENT

Phacoemulsification

During surgery, a special instrument breaks apart the old Lens with Ultrasound.

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Middle

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Extracapsular Surgery

During Extracapsular Surgery, an incision slightly larger than for Phacoemulsification is made in the eye and the Lens Nucleus is removed, leaving the rear Capsule of the lens intact. Leaving the Posterior Capsule reduces the risk of complications later on. The Intraocula Lens is then implanted behind the Iris.

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Posterior Chamber Lens Implant

A Posterior Chamber Lens Implant is similar to a contact lens, with one big difference: The Intraocula Lens is an internal and permanent part of the Eye. An Intraocula Lens is placed in the posterior chamber (an area behind the Iris).

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Conclusion

The Intraocular Lens (IOL) does much the same thing as your old lens did before it become cloudy. It focuses light, letting you see sharply and in vivid color. The IOL Normally lasts a lifetime.

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Laser Treatment After Cataract Surgery

Months or years after Cataract Surgery, vision may become blurry again. This is not another Cataract, but the natural Capsule that holds the Intraocula Lens has become cloudy. This cloudy Capsule is called a Secondary Cataract or After Cataract and can be treated quickly and painlessly in the doctor's office with Laser Surgery.

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Ben Moore        Physics Assignment        Cataracts

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