Lasik Eyes Surgery - Is it essential to remove soft contacts days before Lasik?

Author

Is it essential to remove soft contacts days before Lasik?

itafran2002@yahoo.com

2004-12-16, 9:25 am

Hi, I had Lasik a few weeks ago to correct myopia of -3.75 in both
eyes with minor astigmatism. Although I'm told it's too early to tell
what the final outcome for my vision will be, I believe I've been
under-corrected. My optometrist measured .-75 in OD and .- 25 in OS,
with a little astigmatism left during my 1week post op visit . It
turned out the surgeon compared the wavescan reading just before
surgery with my optometrist's pre-op reading (which was done 3 weeks
prior, while I was still wearing contact lenses), and decided that
wavescan was picking up extra myopia and extra astigmatism I didn't
really have, so he recommended conventional lasik. Not knowing that he
was referring to the old reading, (he simply said, 'your readings do
not match') I accepted his recommendation.

Surgery went well, except of course, I'm still myopic, and the
astigmatism doesn't help while reading at a distance. My far distance
vision is not the same as it used to be with contacts-- this is
annoying when trying to read signs on the freeway, for example, but I
would say my vision is pretty good in all other cases.

Although the surgeon will never admit it, I have a strong suspicion he
never did notice the date of the preop reading, and to justify his
reasoning for not choosing wavefront and basing his surgery on the
preop reading, he said that it really didn't matter if I was still
wearing contacts while my preop reading was done, as soft contacts
don't really change the shape of the cornea. Why then does every
surgeon ask you remove them for at least 1 week prior? Is the surgeon
trying to cover up ? He said my vision may still improve over 3
months and even get to 20/20. Is this feasible?

I would like to go back for an enhancement, but I'm not sure I should
have the same surgeon, and I'm afraid of the risks of a second surgery.
Are there any statistics for successful 2nd time fixes?
thanks for any info.

Glenn - USAEyes.org

2004-12-16, 9:25 am

I really don't like your surgeon's response either, but all things
considered, your situation could be much worse.

Being off 0.75 diopters is not all that unusual, whether it be with
conventional or wavefront. For all the technology, refractive surgery
is not as precise as the ads make it appear to be. It is impossible
to say if wavefront would have done a better job. Probably, but you
will never know for sure.

Whether or not the doctor noticed the three week difference and knew
that you had not been out of contacts very long before the first
wavescan, the doctor was absolutely correct to not do a
wavefront-guided ablation if the previous and current readings did not
match. Also, the wavefront lower order aberration readings (myopia
and astigmatism) need to be very close to your subjective refraction
(which is better, one or two) for the doctor to use wavefront safely.
The doctor made the right decision, but apparently for the wrong
reasons.

I'm sure that if the left hand knew exactly what the right hand had
done and when it was done and everyone compared notes twice, they
could have taken a third wavefront analysis to determine if wavefront
would have been appropriate.

Let's move on to your future.

Your age is going to be very important. If you are near age 40 you
probably should do absolutely nothing. At around age 40 your eye will
noticeably lose its ability to change focus from distance to near.
This is called presbyopia and is when people need reading glasses or
bifocals to see things near.

There are two ways to describe myopia (nearsighted). One is that you
cannot see things far away very well and the other is that you can see
things close just fine. Being a little nearsighted is not only
advantageous when you are presbyopic, but people with normal vision go
out and have surgery to BECOME a little nearsighted. You may want to
read about monovision at
http://www.usaeyes.org/faq/subjects/monovision.htm

If you decide to have enhancement surgery, evaluate everything with
the same diligence as you did with the first. There is an advantage
with the second surgery in that a flap will not need to be cut. The
existing flap will be able to be lifted. Also, the doctor knows
better how your cornea will respond.

I most emphatically recommend that you NOT have additional surgery on
the eye that is 0.25 diopters myopic. The other eye that is 0.75 is
very close, but in my opinion doing surgery for a 0.25 change is not
only foolish but downright dangerous.

The probability of putting you into hyperopia (farsighted) is in my
opinion way to high to go through the risk of surgery and the risk of
being hyperopic. Ask anyone who is farsighted and you will know that
this is NOT something you want, especially when you are at age 40 and
become presbyopic. Presbyopic hyperopes tend to have poor quality
vision at nearly all distances.

If the 0.75 diaper eye is really bothering you, then maybe (emphasis
on maybe) an enhancement surgery would be appropriate. But the 0.25
eye should be left alone.

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.

Dr. Leukoma

2004-12-16, 9:25 am

itafran2002@yahoo.com wrote in
news:1102744294.868072.173230@z14g2000cwz.googlegroups.com:

> Hi, I had Lasik a few weeks ago to correct myopia of -3.75 in both
> eyes with minor astigmatism. Although I'm told it's too early to tell
> what the final outcome for my vision will be, I believe I've been
> under-corrected. My optometrist measured .-75 in OD and .- 25 in OS,
> with a little astigmatism left during my 1week post op visit . It
> turned out the surgeon compared the wavescan reading just before
> surgery with my optometrist's pre-op reading (which was done 3 weeks
> prior, while I was still wearing contact lenses), and decided that
> wavescan was picking up extra myopia and extra astigmatism I didn't
> really have, so he recommended conventional lasik. Not knowing that he
> was referring to the old reading, (he simply said, 'your readings do
> not match') I accepted his recommendation.
>
> Surgery went well, except of course, I'm still myopic, and the
> astigmatism doesn't help while reading at a distance. My far distance
> vision is not the same as it used to be with contacts-- this is
> annoying when trying to read signs on the freeway, for example, but I
> would say my vision is pretty good in all other cases.
>
> Although the surgeon will never admit it, I have a strong suspicion he
> never did notice the date of the preop reading, and to justify his
> reasoning for not choosing wavefront and basing his surgery on the
> preop reading, he said that it really didn't matter if I was still
> wearing contacts while my preop reading was done, as soft contacts
> don't really change the shape of the cornea. Why then does every
> surgeon ask you remove them for at least 1 week prior? Is the surgeon
> trying to cover up ? He said my vision may still improve over 3
> months and even get to 20/20. Is this feasible?
>
> I would like to go back for an enhancement, but I'm not sure I should
> have the same surgeon, and I'm afraid of the risks of a second surgery.
> Are there any statistics for successful 2nd time fixes?
> thanks for any info.
>
>

The idea that soft contact lenses cannot alter the shape of the cornea is
just plain wrong. This is especially true for thicker lenses such as toric
soft lenses that are worn to correct astigmatism.

Glenn, I think that this is an area where CRSQA should take note of.

DrG

itafran2002@yahoo.com

2004-12-16, 9:25 am

Glen,
thank your for your feedback and suggestions. Yes, I'm 40 and I'm
aware in a few years presbyopia may appear. I'm also concerned about
the additional risk another surgery may bring... I agree with your
recommendation of not touching the -.25 eye, which is also my dominant
eye. What bothers me most is the astigmatism, really, seeing the
letters just a bit 'off', as if there were a slight ghosting.
Obviously I need to go through another couple of readings to see how my
vision changes, before I make my decision. I consider myself fortunate
at not having any of the typical symptoms (such as starbursts, or
halos, etc.).

In your opinion, is it better to have an enhancement after the typical
3-month wait so that the flap is still somewhat 'soft', or let more
time go by? The surgeon mentioned that if my next two readings (to be
taken this month and the next) are consistent I may have it done.

Glenn - USAEyes.org wrote:
> I really don't like your surgeon's response either, but all things
> considered, your situation could be much worse.
>
> Being off 0.75 diopters is not all that unusual, whether it be with
> conventional or wavefront. For all the technology, refractive
surgery
> is not as precise as the ads make it appear to be. It is impossible
> to say if wavefront would have done a better job. Probably, but you
> will never know for sure.
>
> Whether or not the doctor noticed the three week difference and knew
> that you had not been out of contacts very long before the first
> wavescan, the doctor was absolutely correct to not do a
> wavefront-guided ablation if the previous and current readings did
not
> match. Also, the wavefront lower order aberration readings (myopia
> and astigmatism) need to be very close to your subjective refraction
> (which is better, one or two) for the doctor to use wavefront safely.
> The doctor made the right decision, but apparently for the wrong
> reasons.
>
> I'm sure that if the left hand knew exactly what the right hand had
> done and when it was done and everyone compared notes twice, they
> could have taken a third wavefront analysis to determine if wavefront
> would have been appropriate.
>
> Let's move on to your future.
>
> Your age is going to be very important. If you are near age 40 you
> probably should do absolutely nothing. At around age 40 your eye
will
> noticeably lose its ability to change focus from distance to near.
> This is called presbyopia and is when people need reading glasses or
> bifocals to see things near.
>
> There are two ways to describe myopia (nearsighted). One is that you
> cannot see things far away very well and the other is that you can
see
> things close just fine. Being a little nearsighted is not only
> advantageous when you are presbyopic, but people with normal vision
go
> out and have surgery to BECOME a little nearsighted. You may want to
> read about monovision at
> http://www.usaeyes.org/faq/subjects/monovision.htm
>
> If you decide to have enhancement surgery, evaluate everything with
> the same diligence as you did with the first. There is an advantage
> with the second surgery in that a flap will not need to be cut. The
> existing flap will be able to be lifted. Also, the doctor knows
> better how your cornea will respond.
>
> I most emphatically recommend that you NOT have additional surgery on
> the eye that is 0.25 diopters myopic. The other eye that is 0.75 is
> very close, but in my opinion doing surgery for a 0.25 change is not
> only foolish but downright dangerous.
>
> The probability of putting you into hyperopia (farsighted) is in my
> opinion way to high to go through the risk of surgery and the risk of
> being hyperopic. Ask anyone who is farsighted and you will know that
> this is NOT something you want, especially when you are at age 40 and
> become presbyopic. Presbyopic hyperopes tend to have poor quality
> vision at nearly all distances.
>
> If the 0.75 diaper eye is really bothering you, then maybe (emphasis
> on maybe) an enhancement surgery would be appropriate. But the 0.25
> eye should be left alone.
>
> 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.

itafran2002@yahoo.com

2004-12-16, 9:25 am

Glen
thank your for your feedback and suggestions. Yes, I'm 40 and I'm
aware in a few years presbyopia may appear. I'm also concerned about
the additional risk another surgery may bring... I tend to agree with
your recommendation of not touching the -.25 eye, which is also my
dominant eye. What bothers me most is the astigmatism, really, seeing
the letters just a bit 'off', as if there were a slight ghosting.
Obviously I need to go through another couple of readings to see how my
vision changes, before I make my decision. I consider myself fortunate
at not having any of the typical symptoms (such as starbursts, or
halos, etc.).

In your opinion, is it better to have an enhancement after the typical
3-month wait so that the flap is still somewhat 'soft', or let more
time go by? The surgeon mentioned that if my next two readings (to be
taken this month and the next) are consistent I may have it done.

John Geekie

2004-12-16, 9:25 am

Hi, I am going to have Lasik surgery early next year. I currently wear
contact lenses 24/7. My optometrist believed that as I wear my soft contact
lenses constantly without a rest that it could alter the shape of the
cornea. To prove this I went with no lens in one eye for 1 week. I went back
after a week to check. And sure enough my vision and cornea had changed
dramatically. I then did a second week with no lens again and the check up
for this second week revealed no great change in my vision or cornea. I am
now going to check the other eye the same way.

Regards,
John

"Glenn - USAEyes.org" <glenn.hageleSTOPSPAM@USAEyes.org> wrote in message
news:fhclr01ifd8ubmbjf3lngkke9ssutr8v90@4ax.com...
>I really don't like your surgeon's response either, but all things
> considered, your situation could be much worse.
>
> Being off 0.75 diopters is not all that unusual, whether it be with
> conventional or wavefront. For all the technology, refractive surgery
> is not as precise as the ads make it appear to be. It is impossible
> to say if wavefront would have done a better job. Probably, but you
> will never know for sure.
>
> Whether or not the doctor noticed the three week difference and knew
> that you had not been out of contacts very long before the first
> wavescan, the doctor was absolutely correct to not do a
> wavefront-guided ablation if the previous and current readings did not
> match. Also, the wavefront lower order aberration readings (myopia
> and astigmatism) need to be very close to your subjective refraction
> (which is better, one or two) for the doctor to use wavefront safely.
> The doctor made the right decision, but apparently for the wrong
> reasons.
>
> I'm sure that if the left hand knew exactly what the right hand had
> done and when it was done and everyone compared notes twice, they
> could have taken a third wavefront analysis to determine if wavefront
> would have been appropriate.
>
> Let's move on to your future.
>
> Your age is going to be very important. If you are near age 40 you
> probably should do absolutely nothing. At around age 40 your eye will
> noticeably lose its ability to change focus from distance to near.
> This is called presbyopia and is when people need reading glasses or
> bifocals to see things near.
>
> There are two ways to describe myopia (nearsighted). One is that you
> cannot see things far away very well and the other is that you can see
> things close just fine. Being a little nearsighted is not only
> advantageous when you are presbyopic, but people with normal vision go
> out and have surgery to BECOME a little nearsighted. You may want to
> read about monovision at
> http://www.usaeyes.org/faq/subjects/monovision.htm
>
> If you decide to have enhancement surgery, evaluate everything with
> the same diligence as you did with the first. There is an advantage
> with the second surgery in that a flap will not need to be cut. The
> existing flap will be able to be lifted. Also, the doctor knows
> better how your cornea will respond.
>
> I most emphatically recommend that you NOT have additional surgery on
> the eye that is 0.25 diopters myopic. The other eye that is 0.75 is
> very close, but in my opinion doing surgery for a 0.25 change is not
> only foolish but downright dangerous.
>
> The probability of putting you into hyperopia (farsighted) is in my
> opinion way to high to go through the risk of surgery and the risk of
> being hyperopic. Ask anyone who is farsighted and you will know that
> this is NOT something you want, especially when you are at age 40 and
> become presbyopic. Presbyopic hyperopes tend to have poor quality
> vision at nearly all distances.
>
> If the 0.75 diaper eye is really bothering you, then maybe (emphasis
> on maybe) an enhancement surgery would be appropriate. But the 0.25
> eye should be left alone.
>
> 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

2004-12-16, 9:25 am

>In your opinion, is it better to have an enhancement after the typical
>3-month wait so that the flap is still somewhat 'soft', or let more
>time go by? The surgeon mentioned that if my next two readings (to be
>taken this month and the next) are consistent I may have it done.

The longer you wait, the more settled down the eye will become. You
will be more certain that the correction being sought is the
correction actually required.

CLAPIKS can work wonders for a small amount of astigmatism, as would
plain 'ol RGP contact lenses.

Many laser systems used today will automatically correct myopia
(nearsighted) when it corrects astigmatism. The ratio is about 0.25
diopter of myopic correction with every 1.00 diopter of astigmatic
correction. This will be a very, very important component of your
decision whether or not to have enhancement 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

2004-12-16, 9:25 am

DrG will probably make a more knowledgeable response to this John, but
it really is not a good idea to wear contact lenses 24/7, even if the
manufacturers tell you it is okay.

One issue regarding abuse of contact lens wear is the reshaping of the
cornea, which you have already addressed, but there are many other
issues that become involved with overuse of contact lenses.

Another problem is oxygenation. Even the very best contact lenses
reduce the amount of oxygen that reaches the cornea. The eye
"breathes" by taking in oxygen through the cornea. Someone who wears
contacts 24/7 is slowly suffocating the eye. Since the eye needs
oxygen, it looks for other sources. Another nearby source of oxygen
is the blood stream. To correct the problem of lack of oxygen at the
cornea, blood vessels will grow into the cornea and can cause vision
limitations.

Another issue is free radical buildup. This gets into the minutia of
optical care, but let's just say it is better to not have a free
radical buildup in the cornea.

Give your eyes a rest now and then. Especially if you are going to
have refractive surgery. I suggest you begin taking your contacts out
at night and continue this regime for at least a few months before
surgery, perhaps longer. Your eye doctor will be able to check and
recheck to see the changes as your eye relaxes more toward a natural
state. When you are getting closer to surgery, read
http://www.usaeyes.org/faq/subjects/contacts.htm for our suggestions,
depending upon type of contact lens.

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

2004-12-16, 9:25 am

I just had a argument with a surgeon about this the other day.

Many of the better doctors are going as short as three days out of
soft non-toric contact lenses. This would be if the patient does not
wear the contacts 24/7. I think this is wrong too, but then they show
me the patient outcomes that don't seem to suffer because of this
short turnaround. As you can see from
http://www.usaeyes.org/faq/subjects/contacts.htm, we are much, much
more conservative on this.

One of the problems on this issue is what is actually going to be
performed. Sometimes the doc is going to do little more than an auto
refraction just to see if the patient is even a candidate. Sometimes
they will take wavefront readings, with the intent of taking a new set
just before surgery. With at least one manufacturer, a new set just
before surgery is a requirement.

Simply put, permanent corrections should not be made on a moving
target. The corneas need to relax to their natural shape before
surgery, no matter how long that takes...period.

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.

Dr. Leukoma

2004-12-16, 9:26 am

Glenn - USAEyes.org <glenn.hageleSTOPSPAM@USAEyes.org> wrote in
news:qqpnr0h2dms155bf10fca6mvcv05qhgt3j@4ax.com:

> DrG will probably make a more knowledgeable response to this John, but
> it really is not a good idea to wear contact lenses 24/7, even if the
> manufacturers tell you it is okay.
>
> One issue regarding abuse of contact lens wear is the reshaping of the
> cornea, which you have already addressed, but there are many other
> issues that become involved with overuse of contact lenses.
>
> Another problem is oxygenation. Even the very best contact lenses
> reduce the amount of oxygen that reaches the cornea. The eye
> "breathes" by taking in oxygen through the cornea. Someone who wears
> contacts 24/7 is slowly suffocating the eye. Since the eye needs
> oxygen, it looks for other sources. Another nearby source of oxygen
> is the blood stream. To correct the problem of lack of oxygen at the
> cornea, blood vessels will grow into the cornea and can cause vision
> limitations.
>
> Another issue is free radical buildup. This gets into the minutia of
> optical care, but let's just say it is better to not have a free
> radical buildup in the cornea.
>
> Give your eyes a rest now and then. Especially if you are going to
> have refractive surgery. I suggest you begin taking your contacts out
> at night and continue this regime for at least a few months before
> surgery, perhaps longer. Your eye doctor will be able to check and
> recheck to see the changes as your eye relaxes more toward a natural
> state. When you are getting closer to surgery, read
> http://www.usaeyes.org/faq/subjects/contacts.htm for our suggestions,
> depending upon type of contact lens.
>
> 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.
>

According to the new standards for overnight wear, a contact lens must have
a minimum dk/t of 87. In fact, some set the bar higher with a dk/t of 125
or greater. This is to prevent corneal swelling and the risk of eye
infection associated with chronic overnight edema. Currently, only
silicone-hydrogel soft lenses or certain RGP lenses meet these criteria.
The Focus Night and Day has a dk/t of 175 and is approved for one month of
continuous wear, whereas older lenses approved for one week of continuous
wear have a dk/t in the neighborhood of 31(Acuvue). Overnight edema can
cause corneal changes such as thinning and loss of epithelial barrier
function and corneal steepening. Another effect of contact lens wear
observed by Ladage et.al. is the slowing of the rate of epithelial cell
division. This is also somewhat related to dk/t as the lower dk lenses
depressed the rate of cell mitosis the most.

Data thus far indicates an incidence of eye infection that is ten times
less with silicone-hydrogel lenses as compared to conventional overnight
wear, due in large measure to the lack of corneal edema and a fully intact
epithelial layer. However, even these lenses can cause temporary changes
in corneal curvature, owing to their increased rigidity.

Modern silicone hydrogel lenses are revolutionizing the industry, and
present a rational and safe alternative to refractive surgery. However, is
30 days of continuous wear the maximum? Stay tuned.

DrG