Lasik Eyes Surgery - Can lasik affect astigmatism only?

Author

Can lasik affect astigmatism only?

itafran2002@yahoo.com

2005-09-24, 2:39 pm

Hi,
I'm thinking of having an enhancement to my Lasik surgery from last
November. All in all my vision is good, but there is some astigmatism
left in both eyes, about -1.00 in my dominant eye and -.75 in the
other. This prevents me from reading properly at a distance and I
really would like to have this corrected. The myopia is virtually gone
from the dominant eye and only -.25 from the other
My question is: is it possible to simply take care of the astigmatism
without affecting the myopia or is there a risk that in touching the
eyes I may become presbyopic?
thanks for any insight
Ita Fran

Richard

2005-09-24, 2:39 pm

itafran2002@yahoo.com wrote in news:1125423035.482971.53620
@g43g2000cwa.googlegroups.com:

> Hi,
> I'm thinking of having an enhancement to my Lasik surgery from last
> November. All in all my vision is good, but there is some astigmatism
> left in both eyes, about -1.00 in my dominant eye and -.75 in the
> other. This prevents me from reading properly at a distance and I
> really would like to have this corrected. The myopia is virtually gone
> from the dominant eye and only -.25 from the other
> My question is: is it possible to simply take care of the astigmatism
> without affecting the myopia or is there a risk that in touching the
> eyes I may become presbyopic?
> thanks for any insight
>

As I understand it, astigmatism alone cannot be corrected with LASIK.

--
Richard

Graeme Hewson

2005-09-24, 2:39 pm

My surgeon mentioned astigmatic keratotomy (AK), and it's probable I'll
go for that next year. It involves making an incision with a scalpel to
relax the cornea in the right plane.

Incidentally, can anyone tell me the relative pro's and cons of AK
versus LRI (limbal relaxing incisions)?

Glenn - USAEyes.org

2005-09-24, 2:39 pm

The physics of current excimer laser technology for LASIK and similar
laser eye surgery available in the US "couples" myopic correction with
astigmatic correction. This coupling effect dictates that for every
1.00 diopter of astigmatic correction there is an automatic myopic
(nearsighted, shortsighted) correction. The ratio ranges from about
0.25 diopter to 0.40 diopter.

It appears that your dominant eye is plano (no spherical refractive
error). This means that if you attempt to have the 1.00 diopter
astigmatism in your dominant eye removed you would end up somewhere
between 0.25 and 0.40 diopters hyperopic (farsighted, longsighted).

If you are young, the eye would probably be able to "focus around" a
small amount of hyperopia.

If you are at or intend to eventually be over age 40, even a small
amount of hyperopia could be a very big problem. At around age 40 the
natural lens of the eye is less able to change focus (presbyopia) and
so you are no longer able to "focus around" the hyperopia. The
combination of hyperopia and presbyopia tends to provide poor vision
at all distances.

It is possible to have hyperopic laser correction to resolve the
hyperopia induced by the attempt to correct the astigmatism, but that
is a lot of manipulation of your cornea and could result in poor
vision quality.

You need to have a very serious talk with your surgeon and discuss the
probability of you becoming hyperopic after surgery. Discuss how this
hyperopia will affect you in the short and long term. Only then can
you decide if the potential benefit is worth the potential risk.

And I very highly recommend you get a second opinion before you make a
final decision.

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.

Ragnar

2005-09-24, 2:39 pm

This is a strange result. The only way I could see that happening is
if you had very little myopia to begin with, and the surgeon did not
remove enough tissue to get rid of all your astigmatism. If he
removed more tissue (as would be the case in correcting moderate to
severe myopia) your astigmatism would have been corrected as a bonus
side-effect. This side-effect occurs in LASIK to treat
nearsightedness since the optical zone is being treated by the laser.
The side effect does NOT occur in H-Lasik which treats farsightedness
since H-Lasik ablates a ring of tissue around the optical zone where
the light enters the eye without ablating any tissue in the optical
zone itself.

On 30 Aug 2005 10:30:35 -0700, itafran2002@yahoo.com wrote:

>Hi,
>I'm thinking of having an enhancement to my Lasik surgery from last
>November. All in all my vision is good, but there is some astigmatism
>left in both eyes, about -1.00 in my dominant eye and -.75 in the
>other. This prevents me from reading properly at a distance and I
>really would like to have this corrected. The myopia is virtually gone
>from the dominant eye and only -.25 from the other
>My question is: is it possible to simply take care of the astigmatism
>without affecting the myopia or is there a risk that in touching the
>eyes I may become presbyopic?
>thanks for any insight
>Ita Fran

Ragnar

2005-09-24, 2:39 pm

yes it can, but is rarely done.
There are other ways to treat astigmatism by itself.

On 30 Aug 2005 19:08:46 GMT, Richard <RichardRapier@netscape.net>
wrote:

>itafran2002@yahoo.com wrote in news:1125423035.482971.53620
>@g43g2000cwa.googlegroups.com:
>
>
>As I understand it, astigmatism alone cannot be corrected with LASIK.

Ragnar

2005-09-24, 2:39 pm

Bingo ghewson!
You win a prize for posting some useful correct information into this
newsgroup! That doesn't happen often!
the cuts you mention are arc cuts made to the periphery of the cornea.
That are essentially cuts made orthogonal (90 degrees) to what would
be the radial cuts of RK. And they now have diamond edged blades in
which no scalpel is used. They are placed on the eye like a cookie
cutter and gently pressed down to a predetermined depth and lifted
off. No other movement of the blade occurs.

On 30 Aug 2005 19:56:28 GMT, ghewson@cix.co.REVERSE:ku (Graeme Hewson)
wrote:

>My surgeon mentioned astigmatic keratotomy (AK), and it's probable I'll
>go for that next year. It involves making an incision with a scalpel to
>relax the cornea in the right plane.
>
>Incidentally, can anyone tell me the relative pro's and cons of AK
>versus LRI (limbal relaxing incisions)?

itafran2002@yahoo.com

2005-09-24, 2:39 pm

Thank you Glenn (and Ragnar) for the detailed info. I had an inkling
it wouldn't be so easy. I did express that doubt with the surgeon and
his reply was that originally the software couldn't distinguish between
the myopia and the astigmatic correction, but now the new software used
can. As you suggest, I may get a second opinion. And yes, my
astigmatism results from the surgeon not trusting the wavescan reading
as it differed from the optometrist pre-op measurements, so I had a
conventional Lasik operation. A conservative choice, but I really wish
I could get rid of the astigmatism now. Sounds like it's quite risky
and I may end up worse off, which I of course don't want....
Anyway, I'll consult with the surgeon AND get a second opinion. Thanks
again, this is a great forum.
Ita Fran

Glenn - USAEyes.org wrote:
> The physics of current excimer laser technology for LASIK and similar
> laser eye surgery available in the US "couples" myopic correction with
> astigmatic correction. This coupling effect dictates that for every
> 1.00 diopter of astigmatic correction there is an automatic myopic
> (nearsighted, shortsighted) correction. The ratio ranges from about
> 0.25 diopter to 0.40 diopter.
>
> It appears that your dominant eye is plano (no spherical refractive
> error). This means that if you attempt to have the 1.00 diopter
> astigmatism in your dominant eye removed you would end up somewhere
> between 0.25 and 0.40 diopters hyperopic (farsighted, longsighted).
>
> If you are young, the eye would probably be able to "focus around" a
> small amount of hyperopia.
>
> If you are at or intend to eventually be over age 40, even a small
> amount of hyperopia could be a very big problem. At around age 40 the
> natural lens of the eye is less able to change focus (presbyopia) and
> so you are no longer able to "focus around" the hyperopia. The
> combination of hyperopia and presbyopia tends to provide poor vision
> at all distances.
>
> It is possible to have hyperopic laser correction to resolve the
> hyperopia induced by the attempt to correct the astigmatism, but that
> is a lot of manipulation of your cornea and could result in poor
> vision quality.
>
> You need to have a very serious talk with your surgeon and discuss the
> probability of you becoming hyperopic after surgery. Discuss how this
> hyperopia will affect you in the short and long term. Only then can
> you decide if the potential benefit is worth the potential risk.
>
> And I very highly recommend you get a second opinion before you make a
> final decision.
>
> 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.

Robert Kopp

2005-09-24, 2:39 pm

"Ragnar" <ragnarsuomi@yahoo.com> wrote in message
news:i4n9h1hql8tf0cgcqd1etlnujlplm3ki01@4ax.com...
> yes it can, but is rarely done.
> There are other ways to treat astigmatism by itself.
>
Like hard contact lenses, for example.

--
Robert T. Kopp
http://analytic.tripod.com

Richard

2005-09-24, 2:39 pm

"Robert Kopp" <koppr@hevanet.com> wrote in
news:11helvki6cku82b@corp.supernews.com:

>
> "Ragnar" <ragnarsuomi@yahoo.com> wrote in message
> news:i4n9h1hql8tf0cgcqd1etlnujlplm3ki01@4ax.com...
> Like hard contact lenses, for example.
>

I have soft disposable contacts that correct my astigmatism, in addition to
correcting my myopia.

--
Richard

Harry

2005-09-24, 2:39 pm

This surgery was discredited some time ago, and has really screwed up
people's vision!

"Ragnar" <ragnarsuomi@yahoo.com> wrote in message
news:27n9h11sr2qbtqi1amggpdfo8gu5l83p0c@4ax.com...[vbcol=seagreen]
> Bingo ghewson!
> You win a prize for posting some useful correct information into this
> newsgroup! That doesn't happen often!
> the cuts you mention are arc cuts made to the periphery of the cornea.
> That are essentially cuts made orthogonal (90 degrees) to what would
> be the radial cuts of RK. And they now have diamond edged blades in
> which no scalpel is used. They are placed on the eye like a cookie
> cutter and gently pressed down to a predetermined depth and lifted
> off. No other movement of the blade occurs.
>
>
> On 30 Aug 2005 19:56:28 GMT, ghewson@cix.co.REVERSE:ku (Graeme Hewson)
> wrote:
>

Harry

2005-09-24, 2:39 pm

I have INDUCED astigmatism from LASIK, on a completely different (worse)
axis. A good
friend had no astigmatism before LASIK. They tried to charge her to correct
astigmatism she
didn't have. She should have paid the extra cash. She walked out of the
surgeon's office with
an optical zone 2mm smaller than her scoptic pupil, no blend, induced
astigmatism... she regressed
half her prescription and has debilitating dry eyes. Her eyes burn painfully
every day.

Stay away from corneal refractive surgery. It's butchery masquerading as
medicine.

"Ragnar" <ragnarsuomi@yahoo.com> wrote in message
news:2qm9h1hus5cto2uj28ogk8124f0i8ah33r@4ax.com...[vbcol=seagreen]
> This is a strange result. The only way I could see that happening is
> if you had very little myopia to begin with, and the surgeon did not
> remove enough tissue to get rid of all your astigmatism. If he
> removed more tissue (as would be the case in correcting moderate to
> severe myopia) your astigmatism would have been corrected as a bonus
> side-effect. This side-effect occurs in LASIK to treat
> nearsightedness since the optical zone is being treated by the laser.
> The side effect does NOT occur in H-Lasik which treats farsightedness
> since H-Lasik ablates a ring of tissue around the optical zone where
> the light enters the eye without ablating any tissue in the optical
> zone itself.
>
>
> On 30 Aug 2005 10:30:35 -0700, itafran2002@yahoo.com wrote:
>

Twisted French Frye

2005-09-24, 2:39 pm

What is "corneal refractive surgery"? Is that laser or lasik vision
correction? I have been thinking of getting lasik vision correction for my
eyes for years now. But I am hesitent. I have bad astigmatism. Not even sure
if I am a candidate. Do they do vision correction on astigmatism eyes? Thank
you for your time in advance.

"Harry" <Harry@nospam.com> wrote in message
news:1125613158.b5065a4a6c1df39d393c8aa9479623ac@teranews...
>I have INDUCED astigmatism from LASIK, on a completely different (worse)
>axis. A good
> friend had no astigmatism before LASIK. They tried to charge her to
> correct astigmatism she
> didn't have. She should have paid the extra cash. She walked out of the
> surgeon's office with
> an optical zone 2mm smaller than her scoptic pupil, no blend, induced
> astigmatism... she regressed
> half her prescription and has debilitating dry eyes. Her eyes burn
> painfully every day.
>
> Stay away from corneal refractive surgery. It's butchery masquerading as
> medicine.
>
>
> "Ragnar" <ragnarsuomi@yahoo.com> wrote in message
> news:2qm9h1hus5cto2uj28ogk8124f0i8ah33r@4ax.com...
>
>

Glenn - USAEyes.org

2005-09-24, 2:39 pm

You will find in this newsgroup a few people who have a mania against
any kind of refractive surgery. That would include LASIK, IntraLASIK,
PRK, LASEK, Epi-LASIK, and CK. With rare exception, these zealots use
hyperbole and misrepresentation to forward their agenda. The previous
post in this thread is a prime example. Most of these posts will
include:

1) A poster who uses more than one alias
2) An unidentified "victim" who is not the poster.
3) The "victim" is reported to have catastrophic symptoms
4) No specifics on the surgeon.
5) No specifics on the surgery other than the reported complications
6) A wide ranging condemnation of
6a) refractive surgeons
6b) laser manufacturers
6c) governmental regulatory agencies
7) The use of terms with shock value such as "butcher", "burn",
"destruction", etc.
8) The poster never identifies him/herself
9) When pressed for specifics, the poster either does not respond or
responds with attacks against the person asking for specifics

I do not recommend that you ignore these posts outright, but consider
the lack of integrity of the information presented. IMO, legitimate
individuals will be willing to identify who they are, present
substantiation of their claims, and do not resort to abusive language.

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.

serebel

2005-09-24, 2:39 pm

Oh heck, I'll say it. I would ignore a rant like Harry's. It's one
thing to state that his outcome is not good, but when he goes on to
state "it's butchery masquerading as medicine", then we know that he's
off the deep end.

SErebel

serebel

2005-09-24, 2:39 pm

mnprescott

2005-09-24, 2:39 pm

Corneal refractive surgery is any one of a number of eye surgeries on the
thin clear covering of your eye called the cornea. Typically the surgeon
uses a laser to fry corneal tissue, removing cornea - in an attempt to
compensate typically for sphere (failure to focus an image properly on the
retina due to the overall shape of your eye (eg.too oblong is myopia).
Sometimes the doctor also attempts to compensate for any astigmatism you may
have. This treatment is often problematic because the doctor must make an
oval treatment zone which makes your treatment zone narrow on one axis which
can cause problems with aberrations. Patients often wind up with induced
astigmatism from refractive procedures.

If your astigmatism is bad, you may be a very bad candidate for refractive
surgery of any kind. A bad outcome can really ruin your life. Treat yourself
to some new glasses and a vacation, and forget about having your eyeballs
cut and fried.

"Twisted French Frye" <noene@nodnga.com> wrote in message
news:VrLRe.73554$DW1.46085@fed1read06...
> What is "corneal refractive surgery"? Is that laser or lasik vision
> correction? I have been thinking of getting lasik vision correction for my
> eyes for years now. But I am hesitent. I have bad astigmatism. Not even
> sure if I am a candidate. Do they do vision correction on astigmatism
> eyes? Thank you for your time in advance.
>
>
>
> "Harry" <Harry@nospam.com> wrote in message
> news:1125613158.b5065a4a6c1df39d393c8aa9479623ac@teranews...
>
>

serebel

2005-09-24, 2:39 pm

mnprescott wrote:
> Corneal refractive surgery is any one of a number of eye surgeries on the
> thin clear covering of your eye called the cornea. Typically the surgeon
> uses a laser to fry corneal tissue, removing cornea - in an attempt to
> compensate typically for sphere (failure to focus an image properly on the
> retina due to the overall shape of your eye (eg.too oblong is myopia).
> Sometimes the doctor also attempts to compensate for any astigmatism you may
> have. This treatment is often problematic because the doctor must make an
> oval treatment zone which makes your treatment zone narrow on one axis which
> can cause problems with aberrations. Patients often wind up with induced
> astigmatism from refractive procedures.
>
> If your astigmatism is bad, you may be a very bad candidate for refractive
> surgery of any kind. A bad outcome can really ruin your life. Treat yourself
> to some new glasses and a vacation, and forget about having your eyeballs
> cut and fried.
>
>
>
Another nut heard from. RS does not "fry" your cornea. Any idiot knows
that if this were the case, the rest of your eye would also be "Fried".
Patients very rarely end up with induced astigmatism, The very often
thing is just the loony battle cry.

SErebel[vbcol=seagreen]
> "Twisted French Frye" <noene@nodnga.com> wrote in message
> news:VrLRe.73554$DW1.46085@fed1read06...

Glenn - USAEyes.org

2005-09-24, 2:39 pm

Check the raw headers. It looks like mnprescott can be added to Brent
Hanson's long list of aliases.

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.

serebel

2005-09-24, 2:39 pm

What's a raw header?

SErebel

Glenn - USAEyes.org

2005-09-24, 2:39 pm

It is information provided by the system of posting a message on an
Internet newsgroup. As an example, here is the header for the post
from mnprescott@aol.com

Path:
newssvr14.news.prodigy.com!newsdbm05.news.prodigy.com!newsdst02.news.prodigy.com!newsmst01b.news.prodigy.com!prodigy.com!newscon06.news.prodigy.com!prodigy.net!border1.nntp.dca.giganews.com!border2.nntp.dca.giganews.com!nntp.giganews.com!newsfeed-east.nnt
pserver.com!nntpserver.com!newsfeed-west.nntpserver.com!manticore.nntpserver.com.POSTED!teranews!not-for-mail
From: "mnprescott" <mnprescott@aol.com>
Newsgroups: alt.lasik-eyes
References: <1125423035.482971.53620@g43g2000cwa.googlegroups.com>
<2qm9h1hus5cto2uj28ogk8124f0i8ah33r@4ax.com>
<1125613158.b5065a4a6c1df39d393c8aa9479623ac@teranews>
<VrLRe.73554$DW1.46085@fed1read06>
Subject: Re: Can lasik affect astigmatism only?
Lines: 80
X-Priority: 3
X-MSMail-Priority: Normal
X-Newsreader: Microsoft Outlook Express 6.00.2900.2180
X-RFC2646: Format=Flowed; Response
X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180
NNTP-Posting-Date: Mon, 05 Sep 2005 17:43:32 EST
Message-ID: <1125960212.9a322658cc45f13f27a6dd1a363393c2@teranews>
X-Abuse-Report: http://www.usenetabuse.com
X-Abuse-Notes: Abuse reports must be submited via the usenetabuse.com
portal listed above.
X-Abuse-Notes2: Reports sent via any other method will not be
processed.
X-Abuse-Notes3: Any other abuse reporting headers in this article are
fraudulent.
X-Orginal-Message-ID:
<oS3Te.392561$3K.256769@manticore.nntpserver.com>
Date: Mon, 5 Sep 2005 18:41:25 -0400
Xref: newsmst01b.news.prodigy.com alt.lasik-eyes:44176

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.

Ragnar

2005-09-24, 2:39 pm

You are full of it.
The tip off is when you said "fry your cornea". Fry indeed.

On Mon, 5 Sep 2005 18:41:25 -0400, "mnprescott" <mnprescott@aol.com>
wrote:

>Corneal refractive surgery is any one of a number of eye surgeries on the
>thin clear covering of your eye called the cornea. Typically the surgeon
>uses a laser to fry corneal tissue, removing cornea - in an attempt to
>compensate typically for sphere (failure to focus an image properly on the
>retina due to the overall shape of your eye (eg.too oblong is myopia).
>Sometimes the doctor also attempts to compensate for any astigmatism you may
>have. This treatment is often problematic because the doctor must make an
>oval treatment zone which makes your treatment zone narrow on one axis which
>can cause problems with aberrations. Patients often wind up with induced
>astigmatism from refractive procedures.
>
>If your astigmatism is bad, you may be a very bad candidate for refractive
>surgery of any kind. A bad outcome can really ruin your life. Treat yourself
>to some new glasses and a vacation, and forget about having your eyeballs
>cut and fried.
>
>
>
>"Twisted French Frye" <noene@nodnga.com> wrote in message
>news:VrLRe.73554$DW1.46085@fed1read06...
>