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Home > Archive > Lasik Eyes Surgery > December 2005 > EPIDEMIC OF CORNEAL WEAKENING AFTER REFRACTIVE SURGERY
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EPIDEMIC OF CORNEAL WEAKENING AFTER REFRACTIVE SURGERY
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| Many are already aware that patients who received the corneal
refractive surgery RK are experiencing a hyperopic regression due to
thinning and stretching of their surgically weakened corneas. Estimates
range about 40%.
Here is an excerpt and link to a comment posted by Optometrist Dr. Greg
Gemoules who specializes in the treatment of patients damaged by
refractive surgery by fitting them with rigid gas permeable contact
lenses.
http://www.asklasikdocs.com/forum/main/3821.html
Says Dr. Gemoules:
"Up to 40% of post-RK patients develop progressive hyperopia because of
peripheral corneal ectasia due to the cornea being weakened by the
incisions. Taking away tissue from the periphery, as is done with PRK
or LASIK will not make the cornea any stronger."
DrG
----------------------------------------------------------------------------------------------------------------------
The trend now is to ablate more tissue in the periphery in an attempt
to reduce spherical aberration that is typically induced by refractive
surgery and is responsible for a portion of the night vision
disturbances and loss of visual quality experience by refractive
surgery patients.
We're just now seeing the long term effects of RK. One would expect
that other corneal refractive surgical procedures, all of which
compromise corneal strength and integrity, will have similar long term
effects.
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| In article <1134479284.499677.95100@g14g2000cwa.googlegroups.com>,
"Eye" <eyetooamdamaged@yahoo.com> wrote:
> We're just now seeing the long term effects of RK. One would expect
> that other corneal refractive surgical procedures, all of which
> compromise corneal strength and integrity, will have similar long term
> effects.
Only a complete pessimist who wants everything to turn out badly for
everyone would "expect" that.
--
~RT
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| Glenn - USAEyes.org 2005-12-13, 12:55 pm |
| >We're just now seeing the long term effects of RK. One would expect
>that other corneal refractive surgical procedures, all of which
>compromise corneal strength and integrity, will have similar long term
>effects.
Certainly the problems of corneal weakening attributed to Radial
Keratotomy (RK) are a warning call, but RK is nothing like current
excimer laser assisted refractive surgery. To make such a comparison
is like comparing a bicycle to a Harley.
For those who don't know, RK is the process of making radial
spoke-like incisions at least 90% through the cornea. A central area
of about 3.0mm remains untouched, although techniques vary. The
incisions cause the cornea to collapse due to weakening. This collapse
provides a central flattening of the cornea and reduction in myopia
(nearsighted, shortsighted) vision.
RK was developed in Japan, but popularized in the Soviet Union where
providing the surgery was significantly less expensive than
manufacturing and distributing spectacles. Remember that in the Soviet
system the government provided everything, so glasses were a
government expense. RK had some moderate success in the US, but never
became anywhere nearly as popular as LASIK.
I do not know of any study to back up my observations, but it appears
from anecdotal information that those who had RK with more than 4
full-length incisions are now developing fluctuation in vision
throughout the day and a shift toward hyperopic (farsighted,
longsighted) vision.
This hyperopic shift experienced by some RK patients is doubly
problematic because many patients with RK are past age 40 and are
developing presbyopia - the inability to focus on objects near. The
combination of hyperopia and presbyopia provides poor vision at almost
all distances. Add to that the fluctuation throughout the day and
there are a lot of unhappy RK campers out there.
While some may compare the now emerging problems of RK as a
bellweather of what will happen with LASIK, they ignore many important
facts. Put simply, LASIK, PRK, LASEK, Epi-LASIK, and IntraLASIK are
nothing like RK.
Even at the time of its popularity, organized ophthalmology was very
strongly split on RK. So split that a group of RK surgeons sued the
American Academy of Ophthalmology because of what they perceived as
anti-RK acts by their own organization.
I just returned from the First International Congress on Corneal
Crosslinking in Zurich Switzerland. Crosslinking is a process to
improve the connections between the long strands of fibrils that make
up the cornea. By increasing the links between the strands, additional
stability is created in the cornea. In the US, Corneal Collagen
Crosslinking with Riboflavin is called C3-R. See
http://www.usaeyes.org/faq/subjects/c3-r.htm
The process of C3-R is remarkably simple. The patient lies down and a
speculum holds open the eye lids. Initially the eyes are soaked for
five minutes with riboflavin (vitamin B2) solution (0.1%
riboflavin-5-phosphate and dextran) until riboflavin is present in the
cornea and anterior chamber.
After the riboflavin has permeated the cornea, a 30 minute application
of UVA light (5.4 J/cm2 at 370 nm) to the central 7 mm of the cornea
is applied. UVA light is combined with reapplication of riboflavin
solution every three minutes
Riboflavin has light energy absorption properties and protects the
iris, lens, and retina from the UVA light.
C3-R, developed by Brian S. Boxer Wachler, MD of Beverly Hills, is
similar to the technique described previously by Wollensak et al
except C3-R does not require removal of the corneal epithelium. The
epithelium is the outermost layer of corneal cells. Because the
epithelium remains intact, the patient does not experience significant
discomfort and vision recovery is immediate.
C3-R has been used to provide corneal stability and even an
improvement from the hyperopic shift for RK patients.
Although very new and needing additional study, C3-R and similar
crosslinking has been performed on more than about 500 eyes in Italy,
Germany, Switzerland, Greece, and the United States.
In addition to RK patients, C3-R has been shown to successfully stop
the progression of keratoconus and refractive surgery induced ectasia.
It has been used with Intacs for advanced cases of keratoconus, and
has been used to strengthen thin corneas to allow PRK to resolve
corneal irregularities.
From the many studies presented at the congress in Zurich, it appears
that C3-R can reliably resolve many issues relating to cornea
instability whether they be caused by natural progression of disease
or induced by refractive surgery...however additional study is
warranted.
Glenn Hagele
Executive Director
USAEyes.org
"Consider and Choose With Confidence"
Email to glenn dot hagele at usaeyes dot org
http://www.USAEyes.org
http://www.ComplicatedEyes.org
I am not a doctor.
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| I read about this too. RK has been obsolete for several years now
because of the bad results. There very well could be something new that
may make lasik almost obsolete. Maybe phakic IOL technology will
improve to the point where its safer and more consisant than lasik plus
IOLs dont even touch your cornea and if IOLs are done right, they
should give vision as good as contact lenses without the discomfort and
drying contact lenses do. There is some long term effects of lasik, ive
seen a number of people regress years after lasik back into myopia due
to corneal bulging or sometimes their eyes just get worse as in an
increase in axial length. This guy PAT on asklasikdocs should have left
his -1.75 and -.75 pescription alone, especially him being 49! Lasik
was not going to help him reduce his dependancy on glasses any further
and he would be needing reading glasses and if he gets overcorrected
like he did, bifocals. Its sad alot of presbyopes take their near
vision for granted and dont understand that a little myopia is their
friend! Now he wants hyperopic lasik. I think he had better leave
things alone before he damages his eyes further
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| Ragnar 2005-12-14, 11:01 am |
| mmm... I don't think it's obsolete for bad results.. RK is obsolete
because they got the lasers working (PRK and LASIK)
A brother of mine and his wife both had RK done for free and they both
got great results from it.
On 13 Dec 2005 17:38:08 -0800, "Ace" <acemanvx@yahoo.com> wrote:
>I read about this too. RK has been obsolete for several years now
>because of the bad results. There very well could be something new that
>may make lasik almost obsolete. Maybe phakic IOL technology will
>improve to the point where its safer and more consisant than lasik plus
>IOLs dont even touch your cornea and if IOLs are done right, they
>should give vision as good as contact lenses without the discomfort and
>drying contact lenses do. There is some long term effects of lasik, ive
>seen a number of people regress years after lasik back into myopia due
>to corneal bulging or sometimes their eyes just get worse as in an
>increase in axial length. This guy PAT on asklasikdocs should have left
>his -1.75 and -.75 pescription alone, especially him being 49! Lasik
>was not going to help him reduce his dependancy on glasses any further
>and he would be needing reading glasses and if he gets overcorrected
>like he did, bifocals. Its sad alot of presbyopes take their near
>vision for granted and dont understand that a little myopia is their
>friend! Now he wants hyperopic lasik. I think he had better leave
>things alone before he damages his eyes further
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| Trulytelling@yahoo.com 2005-12-14, 6:01 pm |
| RK is obsolete because it screwed so many people up, like LASIK. Which
is becoming obsolete.
Yeah, and everybody knows somebody who smoked all their life and didn't
get cancer. Doesn't mean it didn't hurt 'em. Doesn't mean smoking isn't
bad for you.
Corneal refractive surgery is bad for eyes. Period. Surgeons know it.
Surgeons should stop doing it.
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| Ragnar 2005-12-14, 6:01 pm |
| you are out of your mind
On 14 Dec 2005 13:21:57 -0800, Trulytelling@yahoo.com wrote:
>RK is obsolete because it screwed so many people up, like LASIK. Which
>is becoming obsolete.
>
>Yeah, and everybody knows somebody who smoked all their life and didn't
>get cancer. Doesn't mean it didn't hurt 'em. Doesn't mean smoking isn't
>bad for you.
>Corneal refractive surgery is bad for eyes. Period. Surgeons know it.
>Surgeons should stop doing it.
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| Scary Thought 2005-12-14, 6:01 pm |
| Brent aka Eye has destroyed the meaning of a original thread over in
Asklasikdocs.com. Here is the original thread:
http://www.asklasikdocs.com/forum/main/3821.html
This thread was all about trying to fix Hyperopia after RK. Nobody in that
thread stated that RK is great. Everyone seems to know why RK creates
progressive Hyperopic eyes. This person just wants a fix to his RK problems
and Dr. Trattler stated that PRK outcomes are coming out good.
Then Brent-Eye steps in as a know-it ALL, see his part in the thread. The
Brent from Wheeling, IL.
Is this Brent-Eye guy a doctor?
This newsgroup sure has its share of misfits. I guess that is why some
boards/lists/newsgroups have moderators.
This newsgroup definately needs to be moderated!
<Trulytelling@yahoo.com> wrote in message
news:1134595317.864001.272250@f14g2000cwb.googlegroups.com...
> RK is obsolete because it screwed so many people up, like LASIK. Which
> is becoming obsolete.
>
> Yeah, and everybody knows somebody who smoked all their life and didn't
> get cancer. Doesn't mean it didn't hurt 'em. Doesn't mean smoking isn't
> bad for you.
> Corneal refractive surgery is bad for eyes. Period. Surgeons know it.
> Surgeons should stop doing it.
>
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| Lasik can treat a wider range of conditions and is more percise than
RK. Would you rather be done with high tech lasers or with a simple
scapal by a skilled surgeon with hopefully a steady hand. Besides RK
wont be good for high myopes like you. RK also has alot more risks than
lasik and its known for poor night vision. Then theres hyperopic shift
with RK. Almost everyone considers RK obsolete in everyway and theres
no arguing when theres wavefront lasik with intralase, the latest tech!
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| Trulytelling@yahoo.com 2005-12-15, 1:03 am |
| Oh Ace, refractive surgery HURTS people. We just know more about the
bad things that happen with RK because the procedure has been around
long enough for the long-term effects to be known.
Want to read some material on intralase, the latest tech as you call
it? Check out this link:
http://lasikflap.com/forum/viewforum.php?f=15
P.S. You do remember that wavefront INDUCES distortions in the cornea,
it doesn't remove them... right?
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| May I paste an excerpt of what ive read?
CONCLUSIONS: Macular hemorrhage may occur after LASIK, even in the
absence of previously identified risk factors, such as high myopia,
pre-existing choroidal neovasculaization, lacquer cracks, and sudden
changes in intraocular pressure associated with microkeratome-assisted
flap creation.
Ace's comments-You are correct when you say lasik damages all eyes.
Actually the damage starts before that, the suction cap used in order
to make the flap is responsable for much of the damage. I know one high
myope who got a detatched retina due to the suction cap raising the
intraoccular pressure. As you know, high myopes have thin, fragile
retinas so damage, including detachment is a concern. This could
explain the loss of BCVA, especially in the absense of spectacle
minification.
A new ocular syndrome has caused chatter among femtosecond laser users
because of an unusual trademark: 20/20 patients with extreme light
sensitivity after LASIK.
Ace's comments-I read about one guy who traded glasses for sunglasses.
He developed photophobia and needed sunglasses at all times outdoors or
in bright indoor lighting.
I later regressed back to myopia with astigmatism in both eyes. LASIK
was a total disaster for me. It didn't deliver on the hype to rid me of
glasses and contacts, it worsened my pre-existing dry eye (my eyes have
burned incessantly for 5 1/2 years since LASIK), it caused a huge
curtain-like floater in one eye, and it destroyed my vision in dim
light.
Ace's comments-This is very common and a disapointment for most. The
astigmastim is really evil because this means the person would need
bifocals. If you have little or no astigmastim, you can probably see
pretty clear from near. The fact remains everyone starting at age 35-40
is still going to need glasses after lasik anyway, be it reading
glasses, glasses to drive, bifocals, etc.
Some people return for more eye surgery if they are undercorrected, but
each surgery has risks!
Ace's comments-thats absolutely true. I have seen people make things
worse when they should have left well enough alone and enjoy the fact
they only needed glasses for driving! One presbyopic guy was slightly
myopic, now hes hyperopic and needs bifocals full time. Why o why didnt
he leave his mild residual myopia alone and enjoy his clear near vision
without reading glasses?
Dr. Charles Casebeer, one of the founders of LASIK has testified in a
deposition that all LASIK patient's eyes are bulging. Sometimes
patients go for retreatments for regression. The regression could be
due to increased bulging of the cornea, so removing more tissue and
making the cornea even thinner sounds like the WORST course of action
to treat regression unless you have demonstrated via artemis scan that
the regression is caused by epithelial thickening and not forward
bulging of the eye.
Ace's comments-this is how some people develop full blown ectasia.
Before getting enhanced, make sure your at risk for ectasia. Also if
you are seeing OK the way things are, DONT get enhanced just for the
sake of it! Too many people get enhanced because they end with "only"
20/30 or 20/40 vision then they end up farsighted, astigmastim, more
aberrations, sometimes even ectasia when all they needed was a thin
pair of glasses for driving!
"P.S. You do remember that wavefront INDUCES distortions in the cornea,
it doesn't remove them... right?"
I believe so. Let me recall the articles:
http://www.escrs.org/eurotimes/May2003/wavefront.asp
http://www.revophth.com/index.asp?page=1_661.htm
http://www.crstoday.com/PDF%20Articles/0205/rs_pcp.html
When comparing wavefront to standard LASIK there was an attempt during
an Ophthalmic devices panel meeting to include the word 'reducing' when
referring to higher order aberrations. Aberrations induced by wavefront
are reduced when compared to standard LASIK, but they are CERTAINLY not
reduced when compared to the virgin eye. Wavefront treatments, in fact,
were found to induce aberrations in virgin eyes in clinical trials. A
conscientious doctor on the panel put the skids under the use of the
term 'reducing' when describing wavefront aberrations. Thank you, Dr.
Bullimore.
-----------------------------------------------
Excerpt:
http://www.fda.gov/ohrms/dockets/ac...ipts/3883t1.doc
DR. WEISS: Can you repeat the first one again?
DR. GRIMMETT: Sure. Wavefront-guided LASIK does not reduce the level of
higher-order aberrations of the preoperative eye.
DR. WEISS: Would that not be confusing to someone? Wouldn't that be
confusing?
DR. GRIMMETT: Michael Grimmett.
It may suggest somehow wording in that wasn't it that the higher-order
aberrations were 20 percent higher than the preop eye in the
wavefront-guided versus what, 80 percent was the number?
PARTICIPANT: Seventy-seven percent.
DR. WEISS: In here, is there any place saying that LASIK itself
increases aberrations and that customized corneal ablation increases
them less than conventional treatment?
DR. GRIMMETT: I think that's the idea.
DR. WEISS: So maybe we could put that wavefront-guided ablation ??
DR. GRIMMETT: Conventional LADARVision LASIK increases higher-order
aberrations by that figure 77 percent while wavefront-guided LASIK
increases them by whatever, 20 percent, whatever the number is, or you
can say reduces them to a 20-percent level, if you want to use the word
"reduces."
DR. BULLIMORE: I would avoid the term "reducing."
-------------------------------------------------
So when you say spherical aberration is 'reduced', it's reduced
compared to WHAT, in what population? Is spherical aberration 'reduced'
for large pupil patients as well (likely NOT). Are total higher order
aberrations decreased?
Please keep in mind that in VISX clinical trials, from the data we have
available... 1 in 5 patients did not hit 20/20 at the 12 month mark.
So wavefront can't even do reliably what glasses can do. Let alone the
induced corneal distortions and fried nerves.
I completely agree with Dr. G on this. The overwhelming liklihood is
that refractive surgeons are still out there giving patients corneal
distortions without their informed consent.
I think patients who do their research will find that the strongest,
healthiest and least aberrated corneas they will ever have are their
virgin corneas.
Do you have any other good articles? Especially on the increase of
aberrations, especially using non-wavefront!
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| Ragnar 2005-12-15, 11:00 am |
| If going from 20/800 to 20/20 is hurting me. Hurt me more please.
On 14 Dec 2005 17:12:19 -0800, Trulytelling@yahoo.com wrote:
>Oh Ace, refractive surgery HURTS people. We just know more about the
>bad things that happen with RK because the procedure has been around
>long enough for the long-term effects to be known.
>
>Want to read some material on intralase, the latest tech as you call
>it? Check out this link:
>
>http://lasikflap.com/forum/viewforum.php?f=15
>
>P.S. You do remember that wavefront INDUCES distortions in the cornea,
>it doesn't remove them... right?
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| CatmanX 2005-12-16, 11:01 am |
| Show some evidence Brent! Where is the study that show this epidemic??
Still full of shit it would seem.
dr grant
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| CatmanX 2005-12-16, 11:01 am |
| No, brent is not a doctor, he is a moron who believes that people who
did not operate on him are responsible for his eye condition. He is a
very sad and sick individual.
dr grant
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| Your the moron Dr. Grant, If you bought a new chevy, and your chevy
dealor sold out to someone else, wouldn't you want someone to still
stand behind your warranty? Wouldn't you think the new owner should
stand behind what the old owner sold you? Are you really a doctror? Do
you stand behind your work?
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| CatmanX 2005-12-17, 6:03 pm |
| Actually, Zig, the warfranty is not offered by the dealer, it is
offered by Chevrolet, or GM as it's parent company.The dealer gets
reimbursed by GM for labour and parts.
If the dealer went broke, you would be able to go to another dealer to
get your car fixed under warranty.
Hanson had a problem that was not due to the surgeon, but how his eye
healed from the surgery. This is not Dr Stein's fault, it is not TLC's
fault and it is not even Hanson's fault. It is just the way his body
responded to the surgery. This is the reason Dr's do mainly Lasik these
days as this response is very uncommon from Lasik.
Sorry to disappoint you.
dr grant
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| I don't think Brent does literature research, but I'll show you an
article about the high rate of hyperopic regression after RK, of which
you should be fully aware if you're even casually associated with any
sort of eyecare profession. You should be completely familiar with the
PERK study.... it's referenced at bottom. I'm actually beginning to
wonder myself if you're really a credentialed practitioner.
Here's an article I pulled out of PubMed:
Notice 54% of RK patients had a hyperopic shift of 1D OR MORE:
Arch Ophthalmol. 1994 May;112(5):614-20. Related Articles, Links
Long-term (5- to 12-year) follow-up of metal-blade radial keratotomy
procedures.
Deitz MR, Sanders DR, Raanan MG, DeLuca M.
Department of Ophthalmology, university of Missouri Kansas City School
of Medicine.
OBJECTIVE: To evaluate the long-term stability of the refractive
outcome after metal-blade radial keratotomy procedures.
DESIGN: A cohort of 146 patients who underwent 225 consecutive
metal-blade radial keratotomy procedures that were performed under a
uniform protocol between November 1979 and August 1981 was monitored
prospectively, with 64% of the patients followed up for at least 5
years.
MAIN OUTCOME MEASURES: Changes in spherical equivalent and changes in
average keratometry were evaluated within the following periods: 3
months to 1 year; 1 to 2 years; 2 to between 3 and 4 years (mean, 3.7
years); between 3 and 4 (mean, 3.7 years) to between 5 and 12 years
(mean, 8.5 years); and 1 to between 5 and 12 years (mean, 8.5 years).
RESULTS: Total mean change in refraction between 1 year and the average
of 8.5 years of follow-up was 1.01 diopters (D) (SD, 1.13 D). At 1
year, 31% of the cases were at least 1 D hyperopic, whereas at an
average of 8.5 years, 48% were at least 1 D hyperopic. Fifty-four
percent of the cases had shifted in the hyperopic direction by 1 D or
more. Stepwise regression analysis failed to identify significant
predictive factors for the hyperopic shifts.
CONCLUSIONS: The trend toward progressive hyperopic shifts within this
cohort has continued with time. Other long-term studies have documented
similar, although somewhat smaller, hyperopic shifts among both
patients treated with metal-blade and patients treated with
diamond-blade procedures. Causative factors for the hyperopic shift
have not been identified. It remains to be seen if eyes undergoing
current, more cautious surgical approaches to radial keratotomy will
also experience this phenomenon.
OK, here's a British RK website describing corneal thinning and
hyperopic shift after RK:
http://www.bsrs2000.fsnet.co.uk/new_page_10.htm
Excerpt;
Surgical outcomes
The Prospective Evaluation of Radial Keratotomy (PERK) study ran in the
United States from 1980-1985, and considered the safety, efficacy,
predictability and stability of a standardised, 8-incision radial
keratotomy procedure. It assessed 793 eyes with a range of
pre-operative myopia between -2.00 and -8.75 D with 88% of eyes
followed for 10 years (Waring et al., 1994).
The PERK study found that 53% of eyes achieved 6/6 unaided vision or
better and 85% achieved 6/12 or better at the end of the 10 year
period. The procedure is more accurate for treating lower degrees of
myopia with 84% of the -2.00 to -3.12D group and 62% of the -3.25 to
-4.37D group, achieving a refractive result between +1.00D and -1.00D
at 1 year post-surgery in the PERK study, but only 38% of the -4.50 to
-8.00D group fall in to this category (Waring et al., 1985).
However, the long-term stability of the refractive result has been
questioned following the detection of a drift towards hyperopia in up
to one third of patients after 4 years (Waring et al., 1991). The 10
year follow up of the PERK study revealed an alarming 43% of eyes with
a hyperopic shift greater than 1.00D from the refractive result
measured at 6 months post-RK (Waring et al., 1994).
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| Did you read what Dr. G said... that RK patients have corneal thinning,
and PRK or LASIK will NOT make the cornea any stronger? Do you
understand, now, the appropriateness of this response? RK patients are
having problems with their weakened corneas, ALL LASIK patients have
forward bulging of the eye from corneal weakening.
Dr. Trattler is saying it is OK to move forward with a surgery, PRK,
that will weaken the cornea even further?
The point is that adding more corneal thinning to an already thinned
cornea is not smart, and should be stopped.
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| CatmanX 2005-12-18, 1:04 am |
| If you knew anything of the procedires, they are not in any way similar
and are treating different parts of the cornea. RK slices through up to
95% of the cornea in anywhere from 4 to 16 incisions that are radially
incised. PRK is a surface ablation treatment. THey can be used
together, although it is not always possible to predict the outcome.
dr grant
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