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Home > Archive > Lasik Eyes Surgery > May 2005 > FDA says LASIK- induced astigmatism OK?
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FDA says LASIK- induced astigmatism OK?
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| FDAgoldminer 2005-05-07, 10:52 pm |
| FDA says induced astigmatism OK?
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Posted Sat August 14 2004 03:30 PM
UNITED STATES OF AMERICA FOOD AND DRUG ADMINISTRATION CENTER FOR DEVICES AND
RADIOLOGICAL HEALTH
OPHTHALMIC DEVICES PANEL MEETING
102ND MEETING FRIDAY NOVEMBER 30, 2001
I found this in a hearing for CK approval, but it gives you an idea of
what's OK by the FDA...
A surgeon can give patients 2 dipopters of induced astigmatism as long as
it's less than 5% of eyes. That's a LOT of blurry vision folks, and for the
record... induced astigmatism was not in my informed consent materials. How
about yours???
"As shown in this slide, the absolute change in refractive cylinder remained
well below the FDA limit of less than 5 percent of eyes with greater than 2
diopters of induced cylinder at all follow-up examinations."
P36 lines 6-9.
http://www.fda.gov/ohrms/dockets/ac...ipts/3806t1.rtf
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| serebel 2005-05-07, 10:52 pm |
| And you want to know what the FDA is doing about your gripes.
SErebel
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| Glenn - USAEyes.org 2005-05-08, 8:57 am |
| CK is a refractive surgery procedure for hyperopia that uses a probe
to apply high radiofrequency (RF) energy into corneal tissue, causing
shrinkage. This controlled shrinkage will reshape the cornea to change
refractive error by changing the curvature of the cornea, making it
steeper.
CK was first FDA approved as a treatment for hyperopia, however
hyperopia treatment with CK has been all but abandoned. Most doctors
prefer the more permanent LASIK, IntraLASIK, PRK, LASEK, Epi-LASIK,
P-IOL, or RLE to resolve hyperopia. Nearly all CK performed today is
NearVision CK for the temporary induction of myopia to improve near
vision in the non-dominant eye of presbyopic hyperopes or presbyopic
emmetropes.
On the rare occasion when astigmatism problems do occur, the quality
of vision may be quite poor and even worse in low light environments,
such as driving at night. CK seems to have a unique healing process
that often resolves part or all of an induced astigmatism problem.
The initial results settle down in about a week, but astigmatism
induced by CK may get worse for a few weeks reaching it's worse point
at about one month postop. Vision then tends to get better with a
final result 60-90 days after surgery. For this reason, immediate
enhancement surgery for induced CK astigmatism or corneal
irregularities may not be appropriate. It may be better to wait,
depending upon the exact nature of the problem.
CK effects are temporary, regressing at a rate of about 1.00 diopter
every 2-3 years after the initial six month healing process.
Eventually, all CK effects will dissipate and the cornea will return
to preoperative levels. Although CK will fully regress, it is not
reversible, per se. Once the procedure has been performed, it is not
possible to "remove" its effects. Only time will dissipate he effects
of CK.
A very important caution would be to not have a permanent surgery to
correct any problem induced solely by CK. The effects from CK are
temporary. If absolutely nothing is done to the eye, eventually all CK
effects will dissipate and the eye will return to its condition before
surgery. What is not wanted is to use a permanent correction
technique, such as LASIK, IntraLASIK, PRK, LASEK, or Epi-LASIK, to
correct temporary problems induced by CK.
As an example, think of astigmatism as a bump on the cornea induced by
CK. LASIK can get rid of that bump, but eventually the CK forces that
caused the bump will dissipate. That would leave you with a hole. You
would go from one problem into another.
If you need enhancement after CK, in nearly every case the only
appropriate enhancement technique would be more CK. Enhancement with
CK, often called "bonus spots", tend to be the best response on the
rare occasion when the desired outcome is not attained with the
initial 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.
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| Sandy - LASIKdisaster.com - LASIKmemorial.com 2005-05-18, 11:45 am |
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Glenn - USAEyes.org wrote:
> If you need enhancement after CK, in nearly every case the only
> appropriate enhancement technique would be more CK. Enhancement with
> CK, often called "bonus spots", tend to be the best response on the
> rare occasion when the desired outcome is not attained with the
> initial surgery.
>
"BONUS SPOTS"??????
That has "enhancement" and "touch up" beat by a long mile!
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| Glenn - USAEyes.org 2005-05-18, 11:45 am |
| Yea, and you don't even pay for those "bonus spots". I admit I could
not help but laugh when I first heard this term used, which was a bit
embarrassing because I was in a symposium full of surgeons. Medicine
is the land of the euphemism.
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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