Title: Refractive Lens Exchange
1Refractive Lens Exchange
2How 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.
3Refractive errors
- Inability to see clearly is often caused by
refractive error. - Four types of refractive error
- Myopia (nearsightedness)
- Hyperopia (farsightedness)
- Astigmatism
- Presbyopia
4Refractive 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
5Refractive 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
6Refractive errors astigmatism
- In astigmatism, the cornea is curved
unevenlyshaped 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
7Refractive 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.
8What 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
9What 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
dont reshape the cornea instead, the eyes
natural lens is either replaced or enhanced by an
implantable lens that helps correct vision.
10What 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.
Typical intraocular lenses (IOLs) used in the
refractive lens exchange (RLE) procedure
11How 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.
12How 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.
A phoropter is used to measure refractive errors
13How 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.
A small incision is made close to the edge of the
cornea, prior to removing the natural lens and
inserting the IOL
14How is the RLE procedure performed?
- A tiny, high-frequency ultrasound instrument is
inserted into the eye to break up center of the
eyes natural, crystalline lens. - The lens is then gently vacuumed out through this
same instrument.
The eyes natural lens is suctioned out through
an incision
15How 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.
IOL in the eye
16Considerations 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.
17Considerations 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.
18Risks 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.
19Is 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.
20Is 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.
21Discuss options and questions with your
ophthalmologist
- With the help of your ophthalmologist, its
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.