Notes
Slide Show
Outline
1
Refractive Lens Exchange
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, 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.
3
Refractive errors
  • Inability to see clearly is often caused by refractive error.


  • Four types of refractive error:
    • Myopia (nearsightedness)
    • Hyperopia (farsightedness)
    • Astigmatism
    • Presbyopia
4
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.
5
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.
6
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.
7
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.
8
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.



9
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.



10
What is Refractive Lens Exchange (RLE)?
  • A non-laser procedure where the natural, non-cataractous, lens of the eye is removed and replaced with an artificial, intraocular lens (IOL).


  • The cornea is not reshaped.


  • Used to treat moderate to high degrees of nearsightedness (myopia), farsightedness (hyperopia) and patients who are not LASIK candidates.
11
How is the RLE procedure performed?
  • The IOL is implanted in a surgical procedure and performed on an outpatient basis under local or topical anesthesia.


    • Procedure takes approximately 15-20 minutes.
    • RLE procedure is exactly the same as routine cataract surgery.
12
How is the RLE procedure performed?
  • In addition to a complete pre-operative eye exam, these measurements are performed to give the surgeon the necessary information to calculate the necessary power of the IOL:
    • Keratometry: measurement of the form and curvature of the cornea.
    • Retinal exam.
    • The axial length of the eye from the cornea to the retina (A-scan).
    • The depth of the anterior chamber.
13
How is the RLE procedure performed?
  • After the eye is numbed with topical or local anesthesia, one to three small incisions are made close to the edge of the cornea.


  • After the procedure, these incisions are usually “self-sealing,” requiring no stitches.


14
How is the RLE procedure performed?
  • A tiny, high-frequency ultrasound instrument is inserted into the eye to break up center of the eye’s natural, crystalline lens.


  • The lens is then gently vacuumed out through this same instrument.
15
How is the RLE procedure performed?
  • An IOL is folded and inserted through the same incision that was made to extract the natural lens.


  • The IOL is then unfolded and placed into the "capsular bag" that originally surrounded the natural lens.
16
Considerations for the RLE procedure
  • May be recommended for patients who have cataracts starting to form.


  • May be recommended for patients with thin corneas who are otherwise not candidates for the LASIK procedure.


  • May be recommended for patients with unusually high refractive error.
17
Considerations against the RLE procedure
  • Patients with significant ocular disease of any type.


  • Patients with a history of retinal detachment.


  • Patients with any reason for increased risk of infection.
18
Risks and possible side effects of RLE surgery
  • Over-correction or under-correction (with a possible need for a re-treatment).


  • Infection.


  • Increased floaters or retinal detachment.


  • Dislocation of implant.
19
Is refractive surgery right for you?
  • Advanced surgical procedures, including refractive lens exchange, are creating more opportunities for people who want to be less dependent on glasses or contacts.


  • Surgery may not entirely 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.


20
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 side effects associated with your case.


21
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.