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Home > Archive > Lasik Eyes Surgery > February 2005 > The Unhealthy Eye
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| Could Minarik or someone else please explain why the eye would be "unhealthy"
after LASIK. I understand that it doesn't heal to 100% the strength as
before, but why would you consider them unhealthy? I don't have dry eyes and
I can see 20/15. Halos at night are minimal, but I do see star bursts around
xenon headlights.
I had a cut on my arm once--is it now unhealthy? I have a scar.
I know someone in his 80s who had triple bypass surgery and now skis 5 miles
a day. Is his heart unhealthy now that it has been operated on?
Please explain what makes the eye the same or different and why my LASIKed
eyes should be considered unhealthy.
thanks.
--
~RT
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Hogwasher, Premier News and Mail for OS X
http://www.asar.com/cgi-bin/product.../hogwasher.html
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| |
| Glenn - USAEyes.org 2005-01-31, 11:54 am |
| I'm a bit curious about this too, but I just dismissed it as
hyperbole.
The process of today's refractive surgery will weaken the structural
strength of the cornea from preoperative levels, but so long as the
eye is healthy to start with and there remains at least 250 microns of
untouched cornea (more is always better), the cornea remains
structurally sound.
The truth is, there are people with natural corneas that are thinner
than the corneas of people who have had some types of refractive
surgery, such as PRK.
As far as the health of the eye is concerned, baring unforeseen
surgery-induced complications, the eye is as healthy after LASIK, PRK,
LASEK, etc. as it was before...but it is changed. That is, after all,
the whole point of refractive surgery.
Glenn Hagele
Executive Director
Council for Refractive Surgery Quality Assurance
Email to glenn dot hagele at usaeyes dot org
http://www.USAEyes.org
http://www.ComplicatedEyes.org
I am not a doctor.
| |
| serebel 2005-01-31, 11:54 am |
| Minarik and the rest of the fringe can't state this as fact. If they
simply spout their agenda loud enough and long enough........ well, you
know.
SErebel
| |
| Bryce Carlson 2005-01-31, 11:54 am |
| Minarik and others like him make these kinds of sweeping claims because they
either are, or desire to pander to, anti-RS zealots. However, having said
that, there are some long-term issues associated with LASIK that should not
be ignored. They are as follows:
(1) Although the flap heals very securely after LASIK, it never again
retains its full pre-LASIK strength. Initially (many weeks), scar tissue
forms around the outer circumference of the flap, securely sealing the flap
edge to the stroma. In time (months), interface bonding, mediated by an
adhesive protein called glycos-aminoglycan, "glues" the flap quite securely
to the stromal bed. Also, collagen fibrils eventually (many months) grow
and extend from the flap into the stromal bed, "stitching" the flap to the
underlying bed. And ultimately (as recently shown by confocal microscopy)
some interleaving of the transected lamellar layers at the interface occurs,
further integrating the flap with the stromal bed. At the conclusion of
this healing process (about two years), it is estimated by most current
research that the corneal flap eventually regains about 50% of its pre-LASIK
strength. Now, that represents a lot of healing, but it is still not as
strong as a virgin cornea. Once you've had LASIK, you've always had LASIK.
(2) The creation of the LASIK flap, as well as the ablation process,
itself, transects a great many of the nerve fibers that innervate and
provide sensation to the cornea. This frequently results in a moderate
post-op dry-eye condition that usually resolves in about two or three
months. However, even after these peripheral corneal nerves regenerate and
the dry-eye symptoms resolve, the innervation of the cornea never again
returns to its pre-LASIK robustness. This is because some of these nerves
never do regenerate. Most do, but some do not. For the vast majority of
LASIK patients this has no long-term implications, but for a small minority,
unfortunately, it does. This problem can occur when a woman with borderline
dry eyes has LASIK, suffers noticeable dry-eye syndrome for a time, then has
the symptoms resolve back to normal for several years, as the corneal nerves
regenerate, only to have it come roaring back much worse then ever when she
enters menopause. This is due to the same hormonal changes that cause
moderate "benign" dry-eye symptoms in many menopausal women, but in a woman
who had mild dry eye to begin with, the severing of the corneal nerves in
LASIK -- and their lack of complete regeneration -- can occasionally cause a
really serious case of "malignant" dry eye in the years during and after
menopause. The solution here is careful pre-op screening of women for
borderline dry-eye syndrome by doctors.
These are really the only two potential long-term issues with LASIK.
Whether they constitute an unhealthy eye, or not, is a matter of opinion and
perspective. Personally, I wouldn't call a LASIK'd eye unhealthy, but it's
never quite as strong or robust as it was pre-LASIK, due to the
considerations, above.
Now, some anti-LASIK zealots would also claim there is increased long-term
risk for (1) retinal detachment, (2) vitreous detachment, (3) optic neuritis
due to arterial ischemia, (4) cataract formation, etc., etc. However, there
is no, I repeat no, evidence whatsoever to back up such perverse wishful
thinking. It is true that there is some anecdotal evidence for a very small
short-term increase in risk for (1), (2), and (3) above*, but no increased
long-term risk, at all. Also, a few researchers have suggested that the
slight intra-ocular increase in aldehydes due to laser ablation may have
cataragenisis potential, but no clinical evidence, whatsoever, has ever been
found to substantiate this conjecture, either.
So, bottom line, once you've had LASIK, you've always had LASIK, but for the
overwhelming vast majority of LASIK patients that has no practical
significance, whatsoever.
Bryce Carlson
* Due to the transient increase (60+ mm Hg) in IOP during the flap resection
"RT" wrote in message news:
> Could Minarik or someone else please explain why the eye would be
> "unhealthy"
> after LASIK. I understand that it doesn't heal to 100% the strength as
> before, but why would you consider them unhealthy? I don't have dry eyes
> and
> I can see 20/15. Halos at night are minimal, but I do see star bursts
> around
> xenon headlights.
>
> I had a cut on my arm once--is it now unhealthy? I have a scar.
> I know someone in his 80s who had triple bypass surgery and now skis 5
> miles
> a day. Is his heart unhealthy now that it has been operated on?
>
> Please explain what makes the eye the same or different and why my LASIKed
> eyes should be considered unhealthy.
>
> Thanks.
>
> --
> ~RT
| |
| Bryce Carlson 2005-01-31, 11:54 am |
| Also, to elaborate further on the issue of the LASIK flap, as Glenn, myself
and others have pointed out before, if the creation of the flap does not
leave at least 250 um of untouched underlying stroma, there is a risk of
developing iatrogenic ectasia, even in otherwise healthy corneas. In
addition, if forme frust keratoconus or sub-clinical pellucid marginal
degeneration exists pre-op, the risk of developing ectasia is high,
regardless of how much stroma is left intact. Fortunately, pre-op
topographies virtually always display the tell-tale astigmatic abnormalities
associated with these conditions. For this reason and others, such
topographies are considered standard of care for pre-op screening.
Bryce Carlson
"Bryce Carlson" <brycarlson@verizon.net> wrote in message
news:HYlLd.573$eD4.449@trnddc05...
> Minarik and others like him make these kinds of sweeping claims because
> they either are, or desire to pander to, anti-RS zealots. However, having
> said that, there are some long-term issues associated with LASIK that
> should not be ignored. They are as follows:
>
> (1) Although the flap heals very securely after LASIK, it never again
> retains its full pre-LASIK strength. Initially (many weeks), scar tissue
> forms around the outer circumference of the flap, securely sealing the
> flap edge to the stroma. In time (months), interface bonding, mediated by
> an adhesive protein called glycos-aminoglycan, "glues" the flap quite
> securely to the stromal bed. Also, collagen fibrils eventually (many
> months) grow and extend from the flap into the stromal bed, "stitching"
> the flap to the underlying bed. And ultimately (as recently shown by
> confocal microscopy) some interleaving of the transected lamellar layers
> at the interface occurs, further integrating the flap with the stromal
> bed. At the conclusion of this healing process (about two years), it is
> estimated by most current research that the corneal flap eventually
> regains about 50% of its pre-LASIK strength. Now, that represents a lot
> of healing, but it is still not as strong as a virgin cornea. Once you've
> had LASIK, you've always had LASIK.
>
> (2) The creation of the LASIK flap, as well as the ablation process,
> itself, transects a great many of the nerve fibers that innervate and
> provide sensation to the cornea. This frequently results in a moderate
> post-op dry-eye condition that usually resolves in about two or three
> months. However, even after these peripheral corneal nerves regenerate
> and the dry-eye symptoms resolve, the innervation of the cornea never
> again returns to its pre-LASIK robustness. This is because some of these
> nerves never do regenerate. Most do, but some do not. For the vast
> majority of LASIK patients this has no long-term implications, but for a
> small minority, unfortunately, it does. This problem can occur when a
> woman with borderline dry eyes has LASIK, suffers noticeable dry-eye
> syndrome for a time, then has the symptoms resolve back to normal for
> several years, as the corneal nerves regenerate, only to have it come
> roaring back much worse then ever when she enters menopause. This is due
> to the same hormonal changes that cause moderate "benign" dry-eye symptoms
> in many menopausal women, but in a woman who had mild dry eye to begin
> with, the severing of the corneal nerves in LASIK -- and their lack of
> complete regeneration -- can occasionally cause a really serious case of
> "malignant" dry eye in the years during and after menopause. The solution
> here is careful pre-op screening of women for borderline dry-eye syndrome
> by doctors.
>
> These are really the only two potential long-term issues with LASIK.
> Whether they constitute an unhealthy eye, or not, is a matter of opinion
> and perspective. Personally, I wouldn't call a LASIK'd eye unhealthy, but
> it's never quite as strong or robust as it was pre-LASIK, due to the
> considerations, above.
>
> Now, some anti-LASIK zealots would also claim there is increased long-term
> risk for (1) retinal detachment, (2) vitreous detachment, (3) optic
> neuritis due to arterial ischemia, (4) cataract formation, etc., etc.
> However, there is no, I repeat no, evidence whatsoever to back up such
> perverse wishful thinking. It is true that there is some anecdotal
> evidence for a very small short-term increase in risk for (1), (2), and
> (3) above*, but no increased long-term risk, at all. Also, a few
> researchers have suggested that the slight intra-ocular increase in
> aldehydes due to laser ablation may have cataragenisis potential, but no
> clinical evidence, whatsoever, has ever been found to substantiate this
> conjecture, either.
>
> So, bottom line, once you've had LASIK, you've always had LASIK, but for
> the overwhelming vast majority of LASIK patients that has no practical
> significance, whatsoever.
>
> Bryce Carlson
>
> * Due to the transient increase (60+ mm Hg) in IOP during the flap
> resection
>
| |
| C. Gates 2005-01-31, 11:54 am |
| Bryce Carlson wrote:
> Now, some anti-LASIK zealots would also claim there is increased long-term
> risk for ... (4) cataract formation, ... However, there
> is no, I repeat no, evidence whatsoever to back up such perverse wishful
> thinking.
A person does not have to be a zealot or "wishful thinker" to believe
there might be a relationship between lasik and cataracts. From my own
personal experience: before I had lasik, I had no cataracts -- not even
a trace. A year after surgery, I had cataracts in both eyes, and one eye
progressed to the point where I had to have an implant. A study done in
Germany did conclude that for some patients, lasik might trigger the
development of cataracts -- and that further investigation was
recommended. (Their concern was with the UV from the instrument, and not
the overall trauma.) As far as I know, a followup study has not been done.
Although Glenn and others believe that a broad, and reliable, database
of patients is "unnecessary," its existence could go a long way to
reveal whether lasik can trigger cataracts -- and if so, when and why.
It could also confirm or refute many other hypotheses about lasik. My
personal experience has not reported in any study, but that does not
mean that there might, or might not, be a relationship between lasik and
cataracts. How many similar cases are out there, unreported? Nobody
knows. That doesn't mean they don't exist. Or that these people with
cataracts are "wishful thinking" on the part of zealots.
Personally, after learning how trauma of any sort can trigger cataracts,
especially in older individuals, I have a "perverse" hypothesis that one
small segment of lasik patients (those over 50) would show a higher
incidence of cataracts over a non-lasik population in the same age
group. I suspect that there would also be a relationship between the
amount of correction (trauma) and frequency and severity of subsequent
cataracts.
Although this might affect only a small segment of lasik patients, it's
the total of all these small, unique segments that add up to a larger
percentage of bad outcomes. And a broad, objective database could
spotlight the causes (and relationships) that lead to these bad
outcomes. With the "baby boomers" moving into active lifestyles in
retirement, this could become a more important issue as time goes on.
Even if it involves only the problems associated with fitting an implant
to an eye that has had refractive surgery.
| |
| doctor_my_eye@msn.com 2005-01-31, 11:54 am |
|
Glenn, I am sure you are aware of the ocular hypertension treatment
study, and how it has lead most eye practitioners to look at corneal
thickness as a risk factor for glaucoma. So, when you make a blanket
statement that "There are people that are born with corneas that are
just 200 microns," I can answer that with a statement just as far out
of left field. "Yes, there are...and they probably have glaucoma."
Bryce and the other posters here have done A WONDERFUL JOB touching on
some of the issues in post-operative LASIK complications. I will add
that other point that large numbers of pre-operative LASIK patients are
pre-operatively clinically depressed or are being treated for
depression, and their surgery can cause a depressive episode. If it
goes poorly, their life is hell. If it goes well, they still find the
sad truth that getting out of glasses never solved their other
self-image problems.
Glenn - USAEyes.org wrote:
> I'm a bit curious about this too, but I just dismissed it as
> hyperbole.
>
> The process of today's refractive surgery will weaken the structural
> strength of the cornea from preoperative levels, but so long as the
> eye is healthy to start with and there remains at least 250 microns
of
> untouched cornea (more is always better), the cornea remains
> structurally sound.
>
> The truth is, there are people with natural corneas that are thinner
> than the corneas of people who have had some types of refractive
> surgery, such as PRK.
>
> As far as the health of the eye is concerned, baring unforeseen
> surgery-induced complications, the eye is as healthy after LASIK,
PRK,
> LASEK, etc. as it was before...but it is changed. That is, after
all,
> the whole point of refractive surgery.
>
>
> Glenn Hagele
> Executive Director
> Council for Refractive Surgery Quality Assurance
>
> Email to glenn dot hagele at usaeyes dot org
>
> http://www.USAEyes.org
> http://www.ComplicatedEyes.org
>
> I am not a doctor.
| |
| Glenn - USAEyes.org 2005-01-31, 11:54 am |
| Yes, different methods to measure intraocular pressure of an eye after
LASIK may be required, but this is not a disease now is it.
I concur that preoperative screening for psychological difficulties
(even seemingly minor) probably should be a requirement before
refractive surgery, but that is not an unhealthy eye either.
Glenn Hagele
Executive Director
Council for Refractive Surgery Quality Assurance
Email to glenn dot hagele at usaeyes dot org
http://www.USAEyes.org
http://www.ComplicatedEyes.org
I am not a doctor.
| |
| ycdbsoya 2005-02-01, 2:46 pm |
| It's nice to have Bryce back. Exact language is always appreciated on
this NG.
It could be that these post RS patients who develop cataracts may just
be victims of an outdoor-focused lifestyle. I know that for me that I
greatly enjoy outdoor activities such as fishing, boating, hunting,
swimming, surfing, hiking, biking, playing and coaching soccer,
baseball, hoops. While I wear a hat and sunglasses most of the time,
I'm sure my UV exposure over the years has been much greater than the
bookworm who sits at home reading under a lamp, thereby giving me
higher cataract risks.
I wonder if a study has been done that examines lifestyle related
impacts of RS patients on cataract generation? I'll think you'll find
the "statistically significant" differences in the crosstabs there.
| |
| Glenn - USAEyes.org 2005-02-01, 2:46 pm |
| A very interesting and reasonable observation, Frank. That would be
an interesting comparison.
Glenn Hagele
Executive Director
Council for Refractive Surgery Quality Assurance
Email to glenn dot hagele at usaeyes dot org
http://www.USAEyes.org
http://www.ComplicatedEyes.org
I am not a doctor.
| |
| Ragnar 2005-02-01, 2:46 pm |
| It's unhealthy in their opinion so they can collect $2000 in treating
you for problems you don't have.
On Mon, 31 Jan 2005 03:06:51 GMT, RT <RTMD24@NOSPAMyahoo.com> wrote:
>Could Minarik or someone else please explain why the eye would be "unhealthy"
>after LASIK. I understand that it doesn't heal to 100% the strength as
>before, but why would you consider them unhealthy? I don't have dry eyes and
>I can see 20/15. Halos at night are minimal, but I do see star bursts around
>xenon headlights.
>
>I had a cut on my arm once--is it now unhealthy? I have a scar.
>I know someone in his 80s who had triple bypass surgery and now skis 5 miles
>a day. Is his heart unhealthy now that it has been operated on?
>
>Please explain what makes the eye the same or different and why my LASIKed
>eyes should be considered unhealthy.
>
>thanks.
| |
| serebel 2005-02-01, 2:46 pm |
| Here goes Minarik again, throwing the psycho-babble crap again, which
has absolutely nothing to do with healthy or unhealthy eyes. This
Roger Davisesque bull is is usually what he spouts when his argument
can't hold water.
SErebel
| |
| Bryce Carlson 2005-02-01, 2:47 pm |
| "Bryce Carlson" wrote in message news:
>
> (snip)
>
> So, bottom line, once you've had LASIK, you've always had LASIK, but for
> the overwhelming vast majority of LASIK patients that has no practical
> significance, whatsoever.
>
> Bryce Carlson
Yes, "for the overwhelming majority of LASIK patients that has no practical
significance, whatsoever" -- except that their vision is a whole lot better
than it used to be.
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