Back to: Human Body / Eye / Vision correction by laser surgery
Choosing
a laser eye surgery procedure
Revised 2008/4/27
- Top of Page -
·
This
diagram show the family of laser surgeries:
·
Popular
procedures:
o
Surface
surgery: PRK (PhotoRefractive
Keratectomy). Not to be confused with RK (Radial Keratotomy, a
procedure consisting of making numerous radial incisions which extend from the
pupil to the periphery of the cornea in a pattern like the spokes of a wheel).
o
Flap
surgery: Intralase Lasik.
·
Compared
to keeping your eye glasses:
o
It is
possible to achieve better vision with a laser surgery because unlike glasses
which only correct for general near/far distance and astigmatism (dues to
fabrication process limitation of lenses) it does not offer a true correction
for the irregularities (aberrations) of your cornea. One should understand that
correcting your vision with a simple prescription for diopters and astigmatism
is a simplification of your case. Laser eye surgery can truly correct the
unique shape of your corneas.
o
Less
chromatic error. When you do not look through the middle of your glass lenses,
you can see the edges of objects get rainbow colors. After laser surgery this
problem no longer exists because you eyes are aligned with what you are looking
at, even if it is not straight ahead of your face.
·
Comparison
of the popular procedures:
|
|
PRK, a
surface surgery |
Intralase Lasik, a flap
surgery |
|
Risk |
Jeroen van der Pol
(source):
In my experience (I'm an Ophthalmologist and performed more than 1000 laser
surgeries) Lasek and PRK are very safe. Comparable to wearing contact lenses.
Complication rate should be under 1% for this type of treatment. Serious
complications like Rolan Yang's unfortunate experience are rare in Lasek
and PRK. |
3 to 5%.
Along with a higher risk than PRK, treatment is more difficult because the
problem is usually located under the flap. Also, risks are
re-applied if there is a need for a later enhancement / correction. |
|
Pain |
Moderate pain for
first 48 hours. Scratchy feeling gone when temporary contacts removed on the
4th day. |
Almost none. |
|
Recovery time |
Vision recovers
over 1 to 3 months. During recovery you keep worrying that your not-so-good
vision may be as-good-as-it-gets. |
1 day or so.
Protective lenses have to be worn at night for the first week. |
|
Correction quality |
The corrected surface
only has a thin epithelium layer of the eye to cover it (re-grown after
surgery). So there is a high level of control over the correction. |
The corrected
surface lies under a 90-100 mm flap. Although this flap is flexible, it
averages the correction over the surface to some extent. There is a risk of
striae (folds) as the flaps tries to adjust to the corrected surface (think
of laying a rug over a non-flat surface). Jeroen van der Pol
(source):
The flap doesn't fit well to the bottom surface after laser treatment of
higher refractive errors (about -4 and higher). This causes wrinkles in flaps
and detracts from good vision. This is probably the reason that vision is in
my experience (but only very slightly) better with Lasek/PRK than with LASIK. See also: Dr Nepple's opinion. |
|
Dry eyes |
Jeroen van der Pol
(source):
You are less likely to get dry eyes after Lasek/PRK although the first year
is usually dryer than before. |
Jeroen van der Pol
(source):
Lasek/PRK doesn't give nearly as many dry eye problems as LASIK. When the cut
is deeper, nerves will be cut more "centrally" and they will take
longer to regenerate or regenerate incompletely. These nerves are necessary
for corneal sensation and have a crucial role in the establishment of a good
tear function and tissue health. |
|
Cornea strength |
Jeroen van der Pol
(source):
The structural integrity of the eye is simply better preserved with
Lasek/PRK. |
Jeroen van der Pol
(source):
The total "depth" of treatment into the cornea is always greater in
LASIK because of the flap that is cut prior to the (same) laser treatment. See also: Dr Nepple's opinion. |
|
Risk of dislodging
a flap |
No such risk. This
is why people involved in contact sports choose this procedure |
Jeroen van der Pol
(source):
I know of several dislodged LASIK-flaps after trauma from personal experience.
A tennis ball springs to mind and a tree branch in another. Vision never
fully recovered. |
|
Epithelium growth
under the flap |
No such risk. |
2 to 3% of the
time, the corneal epithelium may be present in the interface. The corneal
epithelium consist of 4 or 5 cell layers that normally cover the surface of
the cornea and protect it. For example, if the corneal flap has a loose edge,
say the first day post-op, the epithelium may choose to grow under the flap
in that particular area and cause problems with vision and stability of the
corneal flap. |
|
Disqualifications |
|
Professional
pilots are not allowed to undergo LASIK but they can get their license with
PRK. People who enjoy
contact sports should not consider Lasik. |
·
More
info on problems related to Lasik:
o
Top 10 reasons not
to get Lasik.
o
Links:
§
Lasik Complications: It has the
purpose of warning people about LASIK complications prior to surgery.
§
LASIK-Flap.com/forum: Active patient
bulletin board and informative research forums. The site does not endorse
refractive surgery because there is abundant evidence in current medical
literature that corneal refractive surgery compromises the ocular health and
visual quality of the eye. The site states that refractive surgery is a violation
of the physicians’ Hippocratic oath to “first, do no harm”.
§
LASIKDisaster.com: Most popular LASIK
patient site on the internet. Exposes the LASIK industry for covering up
complications and deceptive advertising. Legal resources for victims of LASIK
medical malpractice. Medical research of LASIK complications and risks. News
articles about LASIK complications. Images of damaged eyes.
§
TheLasikReport.com: A comprehensive
review of the medical literature of LASIK. Examines medical studies which
reveal the risks and long-term complications of LASIK. The report concludes
that LASIK in an inherently harmful procedure and should be abandoned.
§
TheVisionCommunity.com: Created
by author and psychologist Roger D. Davis, PhD, this site features
photorealistic images of the visual aberrations induced by LASIK and other
refractive surgeries, including starbursting, halos, glare, ghosting, blurry
vision, and night driving scenes. Also contain numerous animations, as well as
simulators that allow patients to approximate and communicate their vision to
friends, family, and physicians. If you want help simulating your vision for
others, start here.
§
LasikMemorial.com:: Dedicated to those
whose lives have been damaged or destroyed by refractive surgery, this site
contains true stories written by the victims themselves. When complications
occur, your life splits in two. There is the person you were before LASIK, and
the person you are now...the person whose dry eyes hurt all the time, the
person who sees multiple images of everything, who can't drive at night, who
can't fulfill his or her responsibilities as a parent, or his or her potential
as a human being, the person who suffers from PTSD, depression, and various
states of dread about the future. You realize that maybe human nature isn't
fundamentally good, or at least that doctors aren't what you thought they were.
§
DoctorMyEye.com: Created by activist
Optometrist Ken Minarik, OD, this site states: "The internet is full of
websites that are owned by laser companies, clinics and LASIK providers that
will tell you all about the good cases and sell you on the “joys” of LASIK. We
will leave the pro-arguments to the salesmen. We are here to talk about things
that go wrong and the people who can help you when it happens. Bookmark this
site, and if you or a loved one are considering LASIK…please read all of our
cautions first. If you or a loved one are suffering from LASIK
complications…welcome to your online support group. We are here for you.".
§
LifeAfterLASIK.com: Created by
dissatisfied patient. Warns about bad doctors that harm patients. Cautions
prospective patients about lasik marketing scams that sell fake certifications
and entice patients into having surgery by downplaying complications. Publishes
stories of patients with bad outcomes. Links to YouTube videos about LASIK
horror stories.
§
LasikFraud.com: Created by patient
activist Brent Hanson, this site states, "Are you planning to have laser
eye surgery at TLC? Are you impressed with TLC's success stories? Do you
believe that TLC will honor their "Lifetime Commitment" to you?... If
you answered yes to any of these four questions, then please read about my
experiences with eye surgery at TLC. Your decision to have eye surgery may
result in permanently damaging results that are devastating to you. You may
also discover that TLC will not back up their "Lifetime Commitment
Program" if they damage your vision. I am going to share my personal story
with you so that you can get a more realistic view of what your experience
could be like. This story is unpleasant for me to tell, but you deserve to know
that TLC personnel are fully capable of damaging your vision, deceiving you,
abandoning you as a patient, harassing you, and threatening you with lawsuits
for speaking out.".
§
FlawedLasik.com: Created by patient
activist Dominic Morgan, this site chronicles Dominic's legal struggle with his
surgeon and with the FDA. The site states, "Most Lasik websites are
advertisements for having Lasik eye surgery. This website is to educate you to
the dangers of having Lasik when you are not a proper candidate. Before you
consider Lasik, you must be sure it can be done safely, and that you are a
proper candidate. I went to a doctor who advertised that anyone who was
nearsighted, farsighted, or had astigmatism could be done safely...that's
almost everybody! I trusted these doctors, and now I'm legally blind. My name
is Dom Morgan, and I tell my story because it may be useful to anyone
considering Lasik.".
§
FDA's Lasik Page: Generally
informative but falls short of adequately warning prospective patients. From
the site, "Some patients lose vision. Some patients lose lines of vision
on the vision chart that cannot be corrected with glasses, contact lenses, or
surgery as a result of treatment. Some patients develop debilitating visual
symptoms. Some patients develop glare, halos, and/or double vision that can
seriously affect nighttime vision. Even with good vision on the vision chart,
some patients do not see as well in situations of low contrast, such as at
night or in fog, after treatment as compared to before treatment.".
§
Wake Up To LASIK: Brief
site written by an optometrist who was recruited to "comanage" Lasik.
From the site: "I was WINED and DINED. Beneath the glow of dimmed chandeliers
in an elegant restaurant, the compliments were blushingly effusive. I was made
to feel so very special. It was seductive. The pitch came at the end of this
dinner: "Dr. X, for every patient you send to our laser center, we'll
collect the $5000 and we'll make sure you get back $2000." "That's an
extravagant amount," I said. "Isn't that a kickback?" "No,
we call it a co-management fee," was the quick reply. "You and I will
manage the patient together. A "kickback" lands us both in jail.
Hehehe.".
·
On the
risk of dislodging a flap after Lasik (source):
|
I found from a
reliable source, WebMd that it does indeed never heal. Basically there is no
scar to bind the flap to the rest of the cornea. It basically floats in
place. http://blogs.webmd.com/eye-on-vision/2005/11/lasik-some-wounds-never-heal.html
This is a link to
a website that shows the strength of the flap is significantly weaker after
surgery and never heals to as strong as a normal eye. The Conclusion was:
"Conversely, the LASIK flap wound margin heals by producing a 10-fold
stronger, peripheral hypercellular fibrotic stromal scar that averages 28.1%
as strong as normal comeal stromal, but displays marked variability." http://www.ncbi.nlm.nih.gov/pubmed/16209440?dopt=Abstract
This is why an accident
can cause a person, who even had Lasik 10 years ago, to have a dislodged
flap. Other people have had a flap dislodged by finger pokes or airbags. There are a lot of
people who say the flap heals, but usually are saying that in order not to scare
people with the technical truth. The flap does become more secure over time,
but it doesn't hold the same integrity it used to. |
·
Advice:
Don't have your eyes treated if the ophthalmologist who performs the treatment
hasn't also examined your eyes beforehand.