What are Phakic Lenses?
Phakic intraocular lenses, or phakic lenses, are lenses made
of plastic or silicone that are implanted into the eye permanently to
reduce a person's need for glasses or contact lenses. Phakic refers
to the fact that the lens is implanted into the eye without removing
the eye's natural lens. During phakic lens implantation surgery, a small
incision is made in the front of the eye. The phakic lens is inserted
through the incision and placed just in front of or just behind the
iris.
For more details on phakic lens
implantation surgery, go to Before,
During and After Surgery
What do they treat?
Phakic lenses are used to correct refractive errors, errors in the
eye's focusing power. Currently all phakic lenses approved by the FDA
are for the correction of nearsightedness (myopia).
The cornea and natural lens of the eye focus light to create an
image on the retina, much like the way the lens of a camera focuses
light to create an image on film. The bending and focusing of light is
also known as refraction. Imperfections in the focusing power of the
eye, called refractive errors, cause images on the retina to be out of
focus or blurred.
People that are nearsighted have more difficulty seeing distant objects
than near objects. For these people, the images of distant objects come
to focus in front of the retina instead of on the retina.
Ideally, phakic lenses cause light
entering the eye to be focused on the retina providing clear distance
vision without the aid of glasses or contact lenses.
Surgery is not required to correct nearsightedness. You can wear glasses
or contact lenses instead to correct your vision. Depending on how nearsighted
you are, and other conditions of your eye, other refractive surgery
(surgery to correct refractive errors) options may be available to you,
including PRK (Photorefractive Keratectomy) and LASIK
(Laser Assisted In-Situ Keratomileusis).
Can they be removed?
Phakic lenses are intended to be permanent. While the lenses can be
surgically removed, return to your previous level of vision or
condition of your eye cannot be guaranteed.
What is the difference between phakic intraocular lenses and intraocular
lenses following cataract surgery?
Phakic intraocular lenses are implanted in the eye without removing
the natural lens. This is in contrast to intraocular lenses that are
implanted into eyes after the eye's cloudy natural lens (cataract) has
been removed during cataract surgery.
US FDA What Are Phakic Lenses?
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