Lasik Eyes Surgery - My story--what to do next

Author

My story--what to do next

Freddie

2005-03-19, 6:22 pm

Hi folks,

Need help with my story..... am farsighted had
lasik on both eyes in fall of 2002, vision improved... however
retreatment was needed in both. retreated my dominanat eye first
however I continue to have halos and starbursts that make night
driving difficult (along with fluxtuating vision quality).. Another
item that seems to happen when I have is Epithelial Sloughing. The
latest suggestion from my doctor is to try wavefront PRK (again on my
dominant
eye first). Had a wavescan which did show HOA which seem to show that
I'm "fixable"... yes, the machine is LadarVision... The OD has
mentioned that
I would have to wait for FDA approval of the procedure before
proceedeing.

my questions.... PRK after Lasik? Is that ok? and do I trust the
machine
that created the HOAs to get rid of them? Waybe I'm simple but if the
HOAs are on a layer under a flap how would PRK fix these? and finally,
what other choices
are there?

Yes, I am seeing my Dr on a regular basis and I've only thought of
these questions recently and will surely ask him the same at my next
appointment.

BTW, guys and gals--please don't get into a pissing contest with each
other :-)

Glenn - USAEyes.org

2005-03-19, 6:22 pm

It appears that you continue to be hyperopic (farsighted), plus you are
having night vision problems that are able to be measured with a
wavefront aberrometer. You are considering PRK on the LASIK flap,
which is probably consistent with a very small amount of hyperopia, but
enough higher order aberrations (HOA) to cause the night vision
problems. Additionally, you are troubled with epithelial sloughing.

There are several areas where I have concerns that I think you need to
discuss with your surgeon.

I believe the idea behind PRK instead of a LASIK enhancement surgery is
due to the epithelial sloughing more than because PRK would be better
to correct the vision problems.

Recurrent epithelial sloughing sometimes will respond well to having
the epithelium removed, applying a light "dusting" of excimer energy
across the cornea, and then allowing the epithelium to regenerate and
cover the treated area. This is assuming, of course, that any dry eye
issues are being managed or are resolved. If you have dry eyes, they
will exacerbate any epithelial weakness.

This "rebooting" of the epithelium with excimer energy has a reasonably
good track record if the eye is otherwise healthy. A concern is
corneal hazing that can occur when excimer energy is applied to a LASIK
flap, but the amount of energy that would be applied is so small that I
doubt it would be an issue, providing your flap is an appropriate
thickness.

I do not suggest the Alcon LADARvision, Wave Light Allegretto, Bausch &
Lomb Technolas, or any flying spot laser for this particular procedure
because it has been found that the older technology broadbeam excimer
lasers, such as the Nidek EC5000 and the Visx S3, do an excellent and
quick job of applying a small and even amount of excimer energy to the
entire treatment area all at one time. Here is one case where newer
technology is not necessarily better.

So, a very small amount of excimer laser energy across the entire
treatment area on top of the LASIK flap after removal of the epithelium
does seem to be a reasonable approach to the epithelial sloughing
problem you have encountered.

Depending upon the size of your flap, the thickness of the flap, the
amount of tissue expected to be removed, and where on the flap that
tissue would be removed, having PRK on top of a LASIK flap may or may
not be a good idea. One of my major concerns whenever there is
treatment on the flap is the issue of actual flap thickness and the
meniscus shape of the flap created with a mechanical microkeratome.

If you had IntraLASIK, with the flap created by the Intralase laser
microkeratome, then your flap is evenly thick throughout. If your flap
was created with a mechanical microkeratome that uses a metal blade, it
is thin at the edge, thickest in the mid periphery, and moderately thin
in the center. This creates a delicate situation with
PRK-on-LASIK-flap procedures. Although the overall flap thickness may
be enough, the flap may be too thin at a spot where the laser wants to
be too thick. This is especially true with wavefront-guided excimer
lasers. Wavefront will create a wonderfully nuanced ablation, but a
map of where it is taking away more tissue and where it is taking away
less is not provided to the doctor. That means that the doctor does
not know for sure if the wavefront-guided ablation is going to go deep
in an area where your meniscus shaped flap is thin. You really do not
want the ablation to go through the flap.

Another little twist to your situation is that no excimer laser is FDA
approved to improve HOA. Neither are any approved for Complex
Wavefront Retreatment (CWR) (see
http://www.usaeyes.org/faq/subjects...visory_Memo.pdf) . Neither
are they approved for PRK on top of a LASIK flap. Heck, for that
matter, the current crop of wavefront-guided excimer lasers are not
approved for PRK. All of these uses are considered off-label.
Off-label may be perfectly appropriate, but they do not give you the
advantage of a peer-reviewed FDA controlled outcome study. You need to
do your homework on these before you make any decision.

In my opinion, the first step is to resolve the epithelial problem and
treat it completely separate of the night vision problem. If you need
removal and excimer treatment, then do that with a broadbeam laser and
wait for the epithelium to heal. If things seem stable, then consider
having that LASIK flap lifted and doing CWR under the flap where it
probably belongs anyway.

Glenn Hagele
Executive Director
Council for Refractive Surgery Quality Assurance

http://www.USAEyes.org
http://www.ComplicatedEyes.org

I am not a doctor.

Freddie

2005-03-19, 6:22 pm

Glenn - USAEyes.org wrote:
> It appears that you continue to be hyperopic (farsighted), plus you
are
> having night vision problems that are able to be measured with a
> wavefront aberrometer. You are considering PRK on the LASIK flap,
> which is probably consistent with a very small amount of hyperopia,
but
> enough higher order aberrations (HOA) to cause the night vision
> problems. Additionally, you are troubled with epithelial sloughing.
>
> There are several areas where I have concerns that I think you need
to
> discuss with your surgeon.
>
> I believe the idea behind PRK instead of a LASIK enhancement surgery
is
> due to the epithelial sloughing more than because PRK would be better
> to correct the vision problems.
True, that is why my surgeon is suggesting PRK
>
> Recurrent epithelial sloughing sometimes will respond well to having
> the epithelium removed, applying a light "dusting" of excimer energy
> across the cornea, and then allowing the epithelium to regenerate and
> cover the treated area. This is assuming, of course, that any dry
eye
> issues are being managed or are resolved. If you have dry eyes, they
> will exacerbate any epithelial weakness.
>
> This "rebooting" of the epithelium with excimer energy has a
reasonably
> good track record if the eye is otherwise healthy. A concern is
> corneal hazing that can occur when excimer energy is applied to a
LASIK
> flap, but the amount of energy that would be applied is so small that
I
> doubt it would be an issue, providing your flap is an appropriate
> thickness.
How would this help? If the epithelium sloughed on each or my 2
previous surgeries why wouldn't it again after this if I did lasik
again? and also, what is a reasonably good track record?
>
> I do not suggest the Alcon LADARvision, Wave Light Allegretto, Bausch
&
> Lomb Technolas, or any flying spot laser for this particular
procedure
> because it has been found that the older technology broadbeam excimer
> lasers, such as the Nidek EC5000 and the Visx S3, do an excellent and
> quick job of applying a small and even amount of excimer energy to
the
> entire treatment area all at one time. Here is one case where newer
> technology is not necessarily better.
>
> So, a very small amount of excimer laser energy across the entire
> treatment area on top of the LASIK flap after removal of the
epithelium
> does seem to be a reasonable approach to the epithelial sloughing
> problem you have encountered.
>
> Depending upon the size of your flap, the thickness of the flap, the
> amount of tissue expected to be removed, and where on the flap that
> tissue would be removed, having PRK on top of a LASIK flap may or may
> not be a good idea. One of my major concerns whenever there is
> treatment on the flap is the issue of actual flap thickness and the
> meniscus shape of the flap created with a mechanical microkeratome.
>
> If you had IntraLASIK, with the flap created by the Intralase laser
> microkeratome, then your flap is evenly thick throughout. If your
flap
> was created with a mechanical microkeratome that uses a metal blade,
it
> is thin at the edge, thickest in the mid periphery, and moderately
thin
> in the center. This creates a delicate situation with
> PRK-on-LASIK-flap procedures. Although the overall flap thickness
may
> be enough, the flap may be too thin at a spot where the laser wants
to
> be too thick. This is especially true with wavefront-guided excimer
> lasers. Wavefront will create a wonderfully nuanced ablation, but a
> map of where it is taking away more tissue and where it is taking
away
> less is not provided to the doctor. That means that the doctor does
> not know for sure if the wavefront-guided ablation is going to go
deep
> in an area where your meniscus shaped flap is thin. You really do
not
> want the ablation to go through the flap.
hmm, no IntraLASIK for me...
>
> Another little twist to your situation is that no excimer laser is
FDA
> approved to improve HOA. Neither are any approved for Complex
> Wavefront Retreatment (CWR) (see
> http://www.usaeyes.org/faq/subjects...visory_Memo.pdf) . Neither
> are they approved for PRK on top of a LASIK flap. Heck, for that
> matter, the current crop of wavefront-guided excimer lasers are not
> approved for PRK. All of these uses are considered off-label.
> Off-label may be perfectly appropriate, but they do not give you the
> advantage of a peer-reviewed FDA controlled outcome study. You need
to
> do your homework on these before you make any decision.
yes, my surgeon has always said to wait for FDA approval
>
> In my opinion, the first step is to resolve the epithelial problem
and
> treat it completely separate of the night vision problem. If you
need
> removal and excimer treatment, then do that with a broadbeam laser
and
> wait for the epithelium to heal. If things seem stable, then
consider
> having that LASIK flap lifted and doing CWR under the flap where it
> probably belongs anyway.

Sounds reasonable, but as I mentioned above I'm not sure how this will
help my epithlial problem.....what complications (beside my comfort
level after surgery) does the epithelial sloughing pose? should I just
do a wavefront lasik?

yes, again, I will ask my surgeon all of these questions and thank you
Glen for taking the time to reply....there is a lot of good information
in this NG after one gets by the noise.

Thanks again.
>
> Glenn Hagele
> Executive Director
> Council for Refractive Surgery Quality Assurance
>
> http://www.USAEyes.org
> http://www.ComplicatedEyes.org
>
> I am not a doctor.