Phakic IOL. 2 How the eye works Light rays enter the eye through the clear cornea, pupil and lens. These light rays are focused directly onto the retina,

Phakic IOL

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How the eye works

• Light rays enter the eye through the clear cornea, pupil and lens.

• These light rays are focused directly onto the retina, the light-sensitive tissue lining the back of the eye.

• The retina converts light rays into impulses, sent through the optic nerve to your brain, where they are recognized as images.

• 70% of the eye's focusing power comes from the cornea and 30% from the lens.

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Refractive errors

• Inability to see clearly is often caused by refractive error.

• Four types of refractive error: Myopia (nearsightedness) Hyperopia (farsightedness) Astigmatism Presbyopia

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Refractive errors: myopia

• In myopia (nearsightedness), there is too much optical power in the eye The distance between the

cornea and the retina may be too long or the power of the cornea and the lens may be too strong.

• Light rays focus in front of the retina instead of on it.

• Close objects will look clear, but distant objects will appear blurred.

Myopia, or nearsightedness

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Refractive errors: hyperopia

• In hyperopia (farsightedness), there is too little optical power.

• The distance between the cornea and the retina may be too short.

• Light rays are focused behind the retina instead of on it.

• In adults (but not children), distant objects will look clear, but close objects will appear blurred.

Hyperopia, or farsightedness

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Refractive errors: astigmatism

• In astigmatism, the cornea is curved unevenly—shaped more like a football than a basketball.

• Light passing through the uneven cornea is focused in two or more locations.

• Distant and close objects may appear blurry.

Astigmatism occurs when light passes through football-shaped cornea and/or lens

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Refractive errors: presbyopia

• Presbyopia is an age-related condition in which your eyes gradually lose the ability to see things up close, because the lens of the aging eye can no longer change shape.

• When we are young, the lens in our eyes is flexible and is able to change focus easily between near and far objects, like an autofocus on a camera.

• At around age 40, this flexibility begins to gradually decrease, making it more difficult to see objects up close, unless the eye has nearsightedness.

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What is refractive surgery?

• A group of outpatient surgical procedures used to alter how your eye focuses light rays on the retina, thereby improving vision and reducing dependence on glasses and contact lenses.

• In most cases, refractive surgery affects the shape of your cornea to redirect how light is focused onto the retina. Popular procedures include LASIK, LASEK, PRK and CK.

Refractive surgery procedure on the cornea

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What is refractive surgery?

• Most refractive surgery is performed on the cornea and affects only the front of your eye, while the rest of your eye will change naturally as you age.

• In some cases, refractive surgery procedures don’t reshape the cornea; instead, the eye’s natural lens is either replaced or enhanced by an implantable lens that helps correct vision.

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What is a phakic intraocular lens (IOL)?

• The word “phakic” describes the state of the eye that still has its natural (crystalline) lens intact.

• A phakic IOL, sometimes known as an implantable contact lens (or ICL), is used to treat high degrees of nearsightedness (myopia). Studies are ongoing to evaluate the treatment of

farsightedness (hyperopia) and astigmatism with the phakic IOL as well.

• The eye’s natural lens is not removed, so patients can retain their pre-existing ability to focus. Two types of phakic IOLs

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How is the phakic IOL procedure performed?

• Performed in a surgical suite.

• A light sedation is usually offered for anxiety.

• Entire procedure usually takes 10 to 20 minutes.

• Anesthetic eyedrops are instilled prior to surgery.

• A laser peripheral iridotomy (LPI) is performed prior to surgery to ensure normal fluid flow inside the eye following phakic IOL insertion.

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• The procedure is performed using one of two methods:

Method 1

• One or more small incisions are made at the junction of the sclera (white part of the eye) and the cornea.

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• The phakic IOL is inserted onto the iris (the colored part of the eye).

The customized IOL is inserted through the incision

The IOL is gently placed into its proper position

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• The incision is repositioned with fine sutures. Sutures are finer than a human hair.

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The IOL firmly in place

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Method 2

• One or more small incisions are made at the junction of the sclera (white part of the eye) and the cornea.

• The phakic IOL is inserted beneath the iris (the colored part of the eye).

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Phakic IOL injected into the eye beneath the iris using an injector

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Phakic IOL rests beneath the iris and above the natural lens of the eye

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Phakic IOL in the eye (in front of the iris) Phakic IOL in the eye (behind the iris)

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• Once the lens is properly positioned inside the eye, it provides the necessary correction to redirect light rays precisely onto the retina.

• Steroid and antibiotic eyedrops will need to be applied for about one week following the surgery as your vision continues to improve.

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Considerations for the phakic IOL procedure

• May be recommended for patients with corneas too thin to safely perform corneal refractive surgery (e.g., LASIK, PRK).

• May be recommended for patients with high degrees of refractive error or significantly dry eyes.

• May result in less visual distortion (aberrations), such as glare and halos, than corneal refractive surgery for a given refractive error.

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Considerations against the phakic IOL procedure

• In some cases, there is not enough room in the eye to accommodate the lens.

Your ophthalmologist (Eye M.D.) will take careful measurements to ensure adequate space in the eye to allow safe placement of the phakic IOL.

• Once the lens is inside the eye, repositioning or removal of the IOL may be required if the lens is at risk of damaging any intraocular structure.

• Presence of cataract.

• History of retinal detachment or other serious retinal disease.

• History of ocular inflammation.

• History of glaucoma.

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Risks and possible side effects of phakic IOL surgery

• Over-correction or under-correction (with a possible need for a re-treatment).

• Because the phakic IOL comes into contact with the delicate structures inside the eye, infection or inflammation may result after the IOL is implanted.

• Haze and halo effect at night.

• Excessive tearing.

• Potential for increased intraocular pressure (IOP).

• Potential for retinal detachment.

• Cataract formation and corneal swelling (infrequent).

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Is phakic IOL surgery right for you?

• Advanced surgical procedures, including phakic IOL, are creating more opportunities for people who want to be less dependent on glasses or contacts.

• Refractive surgery may not totally eliminate your need for corrective lenses. Glasses/contacts may still be needed for activities such as fine or detailed work, reading and perhaps night driving.

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Is refractive surgery right for you?

• A large part of the success of any refractive surgery depends on your understanding of the procedure and your expectations.

• Since refractive surgery is an elective procedure, you have the opportunity and responsibility to become fully informed about its risks and benefits.

• Your ophthalmologist will explain the specific technique, its benefits, as well as possible risks and/or side effects associated with your particular case.

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Discuss options and questions with your ophthalmologist

• With the help of your ophthalmologist, it’s ultimately your responsibility to weigh the risks and side effects of a procedure with the benefits it has to offer.

• If you decide refractive surgery is right for you, you may join millions of people who have reduced their dependence on glasses or contacts.

Documents

Phakic IOL. 2 How the eye works Light rays enter the eye through the clear cornea, pupil and lens. These light rays are focused directly onto the retina,