This document discusses accommodative and multifocal intraocular lenses (IOLs) that are surgically implanted to replace the eye's natural lens and help restore vision and the ability to focus at different distances. It provides information on how the eye works, common refractive errors, the IOL procedure, types of IOLs including multifocal and accommodative IOLs, risks and considerations, and whether refractive surgery is right for a given patient.

1. Cataract Surgery
Dr B Farpour
Geneva 2017
www.visionlaser.ch
Accommodative and Multifocal
Intra Ocular Lenses
Geneva refractive public education lectures
Courtesy of AAO
presentation support

2. Accommodative and Multifocal IOLs
• 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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How the eye works
Eye anatomy

3. Accommodative and Multifocal IOLs 3
How the eye works

4. Accommodative and Multifocal IOLs
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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5. Accommodative and Multifocal IOLs
• 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.
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Refractive errors: myopia
Myopia, or nearsightedness

6. Accommodative and Multifocal IOLs
• 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.
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Refractive errors: hyperopia
Hyperopia, or farsightedness

7. Accommodative and Multifocal IOLs
• 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.
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Refractive errors: astigmatism
Astigmatism occurs when light passes
through football-shaped cornea and/or
lens.

8. Accommodative and Multifocal IOLs
• 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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Refractive errors: presbyopia

9. Accommodative and Multifocal IOLs
What is accommodation?
• The eye’s lens, which provides your focusing power, has four
primary functions:
• Transparency: to provide a clear medium through which light rays
from an object can reach your retina
• Optical: to focus a sharp image of an object on the retina
• Anatomic: to create a functional barrier between the anterior and
posterior segments of the eye
• Accommodation: to vary the eye’s refractive power, thus providing
clear images of objects over a wide range of distances
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10. Accommodative and Multifocal IOLs
• Refractive surgery is 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 and PRK.
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What is refractive surgery?
Refractive
surgery
procedure on
the cornea

11. Accommodative and Multifocal IOLs
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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12. Accommodative and Multifocal IOLs
What are accommodative and multifocal intraocular
lenses (IOLs)?
• They are artificial lenses that are
surgically implanted in the eye,
replacing the eye’s natural lens.
• They enable your eye to regain its
focusing and refractive ability.
• The cornea is not reshaped.
• They are used to treat
nearsightedness (myopia),
farsightedness (hyperopia) and the
inability to focus at near distance
with age (presbyopia).
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13. Accommodative and Multifocal IOLs
• A multifocal lens has several rings
of different powers built into the
lens.
• The part of the lens (ring) you look
through will determine if you see
clearly at a far, near or
intermediate distance (this is
sometimes called pseudo-
accommodation).
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What is a multifocal IOL?
A type of multifocal IOL

14. Accommodative and Multifocal IOLs
• The accommodative IOL is hinged
to work in coordination with the eye
muscles.
• The design allows the
accommodative lens to move
forward as the eye focuses on near
objects, and move backward as it
focuses on distant objects.
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What is an accommodative IOL?
A type of accommodative IOL

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What is a multifocal IOL?

16. Accommodative and Multifocal IOLs 16
What is an accommodative IOL?

17. Accommodative and Multifocal IOLs
How is the IOL procedure performed?
• The IOL is implanted in a surgical procedure, performed on an
outpatient basis under local anesthesia and taking approximately
20 to 30 minutes.
• The procedure is very similar to cataract surgery, which is a
common procedure with a high success rate. However, a different
IOL is used for this refractive surgery.
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18. Accommodative and Multifocal IOLs
• In addition to a preoperative eye exam, measurements of the eye are
taken to give the surgeon the necessary information to perform the
procedure. These measurements include:
 Refractive error measurement
 Pupil evaluation and size measurement
 Keratometry: measurement of the form and curvature of the cornea
 A-scan: measurement of the axial length of the eye from the cornea to the retina
 Calculations to determine the correct power of lens (IOL) to use
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How is the IOL procedure performed?
A phoropter is used
to measure refractive
errors.

19. Accommodative and Multifocal IOLs
• 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.
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How is the IOL procedure performed?
Small incisions are made close to the
edge of the cornea for inserting the IOL.

20. Accommodative and Multifocal IOLs
• A tiny, high-frequency
ultrasound instrument is
inserted into the eye to break up
the center of the eye’s natural,
crystalline lens.
• The natural lens is then gently
vacuumed out through one of
the incisions.
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How is the IOL procedure performed?
The eye’s natural lens is suctioned out
through an incision.

21. Accommodative and Multifocal IOLs
• An IOL is folded and inserted
through the same incision that
was used to extract the natural
lens.
• The IOL is then unfolded and
placed into the "capsular bag"
that originally surrounded the
natural lens.
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How is the IOL procedure performed?
IOL in the eye

22. Accommodative and Multifocal IOLs
• Once the accommodative or
multifocal IOL is implanted,
your eye can focus on near,
intermediate and far distances.
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How is the IOL procedure performed?
The IOL firmly in place

23. Accommodative and Multifocal IOLs
Considerations for the accommodative/multifocal IOL procedure
• May be an option for people with cataracts or people without
cataracts who are presbyopic and want to reduce or eliminate their
need for glasses.
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24. Accommodative and Multifocal IOLs
Considerations against the accommodative/multifocal IOL procedure
• The focusing ability of the lens may not be fully realized for six to
eight weeks after the procedure.
• Your eye must relearn how to focus on objects at various distances
in order to see clearly.
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25. Accommodative and Multifocal IOLs
Risks and possible side effects of accommodative/multifocal IOL surgery
• Overcorrection or undercorrection (with a possible need for
retreatment)
• Infection
• Increased floaters or retinal detachment
• Dislocation of implant
• Loss of vision
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26. Accommodative and Multifocal IOLs
Is refractive surgery right for you?
• Advanced surgical procedures, including accommodative and
multifocal IOLs, 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 or contacts may still be needed for activities such as fine or
detailed work, reading and perhaps night driving.
• If an accommodative or multifocal IOL is used, then reading as well
as distance vision may be improved.
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27. Accommodative and Multifocal IOLs
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.
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28. Accommodative and Multifocal IOLs
• 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.
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Discuss options and questions with your ophthalmologist

29. Accommodative and Multifocal IOLs