Phakic Intraocular Lenses (cont.)
What are the Risks?Implanting a phakic lens involves a surgical
procedure. As in any other medical procedure, there are
risks involved. That's why it is important for you to
understand the limitations and potential risks of phakic
intraocular lens implant surgery.
Before undergoing surgery for implantation of a
phakic intraocular lens, you should carefully weigh the
risks and benefits and try to avoid being influenced by
other people encouraging you to do it.
Risks
- You may lose vision. Some
patients lose vision as a result of phakic lens implant surgery that cannot be
corrected with glasses, contact lenses, or another surgery. The amount of
vision loss may be severe.
- You may develop debilitating visual
symptoms. Some patients develop glare, halos, double vision, and/or
decreased vision in situations of low level lighting that can cause difficulty
with performing tasks, such as driving, particularly at night or under foggy
conditions.
- You may need additional eye surgery to
reposition, replace or remove the phakic lens
implant. These
surgeries may be necessary for your safety or to improve your visual function.
If the lens power is not right, then a phakic lens exchange may be needed. You
may also have to have the lens repositioned, removed, or replaced, if the lens
does not stay in the right place, is not the right size, and/or causes
debilitating visual symptoms. Every additional surgical procedure has its own
risks.
- You may be under treated or over
treated. A significant proportion of treated patients do not achieve
20/20 vision after surgery. The power of the implanted phakic lens may be too
strong or too weak. This is because of the difficulties with determining
exactly what power lens you need. This means that you will probably still need
glasses or contact lenses to perform at least some tasks. For example, you may
need glasses for reading, even if you did not need them before surgery. This
also means that you may need a second surgery to replace the lens with
another, if the power of the originally implanted lens was too far from what
you needed.
- You may develop increased intraocular
pressure. You may experience increased pressure inside the eye
after surgery, which may require surgery or medication to control. You may
need long-term treatment with glaucoma medications. If the pressure is too
high for too long, you may lose vision.
- Your cornea may become cloudy. The endothelial cells of your cornea are a thin layer of cells
responsible for pumping fluid out of the cornea to keep it clear. If the
endothelial cells become too few in number, the endothelial cell pump will
fail and the cornea will become cloudy, resulting in loss of vision. You start
with a certain number of cells at birth, and this number continuously
decreases as you age, since these cells are not replenished. Normally, you die
from old age before the number of endothelial cells becomes so low that your
cornea becomes cloudy. Some lens designs have shown that their implantation
causes endothelial cells to be lost at a faster rate than normal. If the
number of endothelial cells drops too low and your cornea becomes cloudy, you
will lose vision and you may require a corneal transplant in order to see more
clearly.
- You may develop a cataract. You may get a cataract, clouding of the natural lens. The amount
of time for a cataract to develop can vary greatly. If the cataract develops
and progresses enough to significantly decrease your vision, you may require
cataract surgery during which both the natural and the phakic lenses will have
to be removed.
- You may develop a retinal detachment.
The retina is the tissue that lines the inside of the back of
your eyeball. It contains the light-sensing cells that collect and send images
to your brain, much like the film in a camera. The risk of the retina becoming
detached from the back of the eye increases after intraocular surgery. It is
not known at this time by how much your risk of retinal detachment will
increase as a result of phakic intraocular lens implantation surgery.
- You may experience infection, bleeding,
or severe inflammation (pain, redness, and decreased
vision).
These are rare complications that can sometimes lead to permanent loss of
vision or loss of the eye.
- Long-term data is not available.
Phakic lenses are a new technology and have only
recently been approved by the FDA. Therefore, there
may be other risks to having phakic lenses implanted
that we don't yet know about.
|
