Title: Accommodative and Multifocal IOLs
1Accommodative and Multifocal IOLs
Insert name/ Practice name/ Logo here if desired
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 accommodation?
- The eyes 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 eyes refractive
power, thus providing clear images of objects
over a wide range of distances.
9What 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
10What 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.
11What are accommodative intraocular lenses (IOLs)
and multifocal intraocular lenses (IOLs)?
- An artificial lens that is surgically implanted
in the eye, replacing the eyes natural lens. - Enables your eye to regain its focusing and
refractive ability. - The cornea is not reshaped.
- Used to treat nearsightedness (myopia),
farsightedness (hyperopia) and the inability to
focus at near with age (presbyopia).
12What is an accommodative intraocular lens (IOL)?
- 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.
A type of accommodative intraocular lens (IOL)
13What is a multifocal IOL?
- 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).
A type of multifocal intraocular lens (IOL)
14How is the IOL procedure performed?
- The IOL is implanted in a surgical procedure,
performed on an outpatient basis under local
anesthesia and taking approximately 20-30
minutes.
15How is the IOL procedure performed?
- In addition to a pre-operative 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.
A phoropter is used to measure refractive errors
16How is the IOL 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.
Small incisions are made close to the edge of the
cornea for inserting the IOL
17How is the IOL procedure performed?
- A tiny, high-frequency ultrasound instrument is
inserted into the eye to break up the center of
the eyes natural, crystalline lens. - The natural lens is then gently vacuumed out
through one of the incisions.
The eyes natural lens is suctioned out through
an incision
18How is the IOL procedure performed?
- 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.
IOL in the eye
19How is the IOL procedure performed?
- Once the accommodative or multifocal IOL is
implanted, your eye can focus on near,
intermediate and far distances.
The IOL firmly in place
20Considerations 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.
21Considerations against the accommodative/multifoca
l IOL procedure
- The focusing ability of the lens may not be fully
realized for six to eight weeks after the
procedure. - Your eye must re-learn how to focus on objects at
various distances in order to see clearly.
22Risks and possible side effects of
accommodative/multifocal IOL surgery
- Over-correction or under-correction (with a
possible need for a re-treatment). - Infection.
- Increased floaters or retinal detachment.
- Dislocation of implant.
- Loss of vision.
23Is 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/contacts may still be
needed for activities such as fine or detailed
work, reading and perhaps night driving. - If an accommodating or multifocal IOL is used,
then reading as well as distance vision may be
improved.
24Is 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.
25Discuss 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.