Runboard.com
Слава Україні!

runboard.com       Sign up (learn about it) | Sign in (lost password?)

Page:  1  2  3 

 
Myope5 Profile
Live feed
Blog
Friends
Miscellaneous info

Head Administrator

Registered: 05-2005
Posts: 816
Karma: 8 (+9/-1)
Reply | Quote
todays wavefront lasik isnt yet perfect


http://www.lasikfraud.com/wavefront_hoax.html


someone whos against lasik posted this in another forum. Theres 34 challenges wavefront needs to overcome. He also claims every eye gets damaged and every eye experiences worse vision. He says the snellen chart does not tell the whole story even if you end up 20/20, you may have a number of quality issues like lost of contrast senestivity, GASH, dry eyes, ectasia, etc.

Gash stands for:
G = Glare
A = arcs
S = starbursts
H = Halos.


I told him while hes correct, very few people have serious complications. He says get one eye lasiked and you wont ever want to touch the other eye after youve seen the differences. This will only work if your a contact wearer and if you cant tolerate contacts, your probably gonna have no choice but lasik the other eye or live with severe ammensteropia(huge refractive difference)
He has nothing positive to say about lasik and even pointed out if people knew all the risks, no one in their right mind would get it. People that do arent fully aware of the risks. I mentioned intacs and he ignored this topic except one time where he just said just about anything is better than lasik.

While im not getting lasik anytime soon, if ever, I understand the position why some would want lasik. I might be alot more tempted if I didnt have mild dry eyes, mild presbyopia and large pupils. Id rather live with glasses than take the risks of lasik which for me are higher than average. I have less to gain, more to lose. Would still need reading glasses anyway.
11/12/2005, 5:43 am Link to this post Send Email to Myope5   Send PM to Myope5
 
Myope5 Profile
Live feed
Blog
Friends
Miscellaneous info

Head Administrator

Registered: 05-2005
Posts: 816
Karma: 8 (+9/-1)
Reply | Quote
Re: todays wavefront lasik isnt yet perfect


>>TC#19

>>Visual quality universally diminished after LASIK

> Not true at all.

ace's two cents: lasik does not always result in diminished vision


>>Hi Ace! People may think they 'see
>>better' because they have better 'uncorrected'
>>vision after LASIK. The ugly truth
>>is that visual quality is universally
>>diminished. Higher order aberrations increase. Contrast
>>sensitivity diminishes.

> If a person says they see
>better after lasik, they do. You
>do not see thru their eyes.
>
ace's two cents: very true. He will argue that they have forgotten what it was like to see with glasses before lasik. Some people have gotten lasik in one eye at a time and they report their lasik eye saw better than their contact lense eye and were so happy they got the other eye done pronto! He also has no good explaination how some people gain line(s) of vision. If someone who had a BCVA of 20/25 with glasses/contacts achieves 20/20 or even 20/15 after lasik, this is clear proof lasik improves vision. If he wants to disagree, tell it to the person why he couldnt see 20/15 with glasses. Its simple: lasik reduced his high order abberations which glasses could do nothing!
>

>>LASIK patients absolutely WILL lose visual quality,
>>will have corneal nerve damage, will
>>have a structurally weakened cornea for
>>the rest of their lives.

> Also not true. Corneal surgeries have
>been around for a lot of
>years. (RK excluded)


ace's two cents: while he is true on corneal nerve damage, in most causes, its mild and never poses a problem ever. I can argue that surgury "damages" you by leaving a scar. Does it affect your quality of life? no. He is correct about having a weakened cornea but as long as 250um remains, risk of ectasia is 1 in 250. If you leave 300um risk is 1 in 5000. Even if ectasia develops, intacs will keep it under control. He is also true that some people DO lose visual quality, especially those 20/10 and 20/15 guys but those seeing less than 20/20 with glasses/contacts have odds greatly in their favor of keeping their quality or improving.

>

>>Patients must be informed of all of
>>these consequences of refractive surgery so
>>that they can decide whether they
>>still believe that the possibility of
>>decreased dependence on glasses is worth
>>racking up so much permanent eye
>>damage.

> Patients are well informed before going
>in. One actually has to read
>the forms.

ace's two cents: As long as they are fully informed, they can rest in peace knowing they went into lasik with an open mind. Those who regretted lasik usually have not properly done their research and were "supprised" If you know about all the risks, GASH, ectasia, lost of contrast, over/under correct, dry eyes, the whole lot and you accept the risks, you cant blame anyone because you knew them all. You took a gamble and was unlucky to be the 1-3% who lost.

>

>>Ace, read this link:http://www.lasikfraud.com/wavefront_hoax.html

>Citing this site as you often do
>gives me the impression that "EYE"
>is Brent Hanson.

>Bulldog


ace's two cents: This is a very informative source that shows the limitation of todays wavefront. This means theres much to improve in the upcomming years but still we have come a long way from "ancient" early lasers which had much higher risks and lower success. I have read alot of websites of people with complications, like over 100 and almost all of them got lasik before the year 2000. A few in the year 2000 or 2001. That was before wavefront, before the new lasers, before intralase. If this was before the year 2000, I would also understandabily be leaning towards being against lasik myself. More and more people will be positive about lasik in the future as complications drop, results improve
11/12/2005, 5:56 am Link to this post Send Email to Myope5   Send PM to Myope5
 
Myope5 Profile
Live feed
Blog
Friends
Miscellaneous info

Head Administrator

Registered: 05-2005
Posts: 816
Karma: 8 (+9/-1)
Reply | Quote
Re: todays wavefront lasik isnt yet perfect


>Ace, we're talking about wavefront keeping its
>promise to reduce a patient's higher
>order aberrations.

Eye, there are thousands of doctors and patients who truely report a decrease of HOA's. Some do experience an increase. If everyone gained more HOA's then whats the point of (wavefront) lasik in the first place? Everyone would lose quality of vision and some also quantity. My 20/30 I get with glasses could become 20/50 and blurry.

>Most of the time
>microkeratomes do not jam and there
>is no infection. But all of
>the time, in normal virgin eyes,
>higher order aberrations are increased by
>wavefront treatments.

Eye, see above.

>Intralase does nothing to
>help this. Actually, intralase leaves a
>really ragged interface compared to some
>microkeratomes.

Eye, thats what I heard but why get a flap in the first place? There is epi-lasik which is just better. A flap increases HOA's

>Any time your flap is
>lifted you can get junk in
>there. There is plenty of junk
>floating around in the air, and
>in your eye already to give
>you junk under the flap. The
>majority of junk under the flap
>is the patient's own meibomian secretions,
>according to one of the doctors
>on Surgical Eyes. Lack of microkeratome
>metal just cuts down on one
>type of junk. There are so
>many more. Did you hear that
>plastic particles are found trapped in
>patients' flaps?


Eye, then go for prk or epi-lasek. No flap and none of the flap problems.


>Eye replied:Reducing the DISASTER of >decentration doesn't
>IMPROVE on a patients total higher
>order aberrations. To improve a patient's
>higher order aberrations you'd have to
>have a perfect surgery AND target
>all the tiny imperfections in the
>eye for real and reduce them.


Eye, this is already being achieved. Well not exactly perfectly but what if someone has so many HOA's he can only see like 20/40 with glasses and has terriable night vision? It would be easy to remove at least some of them because there just is so many to start with. I however would not reccomend lasik on someone seeing better than 20/20 with glasses and especially NOT at 20/10!


>It doesn't happen. Even if decentrations
>have been reduced it doesn't mean
>that higher order aberrations decrease.

Eye, see above.


>Eye replied:None of the challenges have been
>met, and they are unlikely to
>be met. Sometimes you just can't
>fight mother nature.


Eye, so by your opinion, one shouldnt try to fight mother nature with glasses nor contacts either? Lasik is just a high tech way to fight mother natures mistakes on your eyes called myopia/hyperopia and/or astigmastim.


>Yes, ACE, I could read the 20/15
>line for a while after LASIK
>(can't now) but it was distorted.
>IT is not all that uncommon
>to have poor quality 20/20 or
>even 20/15 vision after LASIK.


Eye, what was your pescription before lasik? what is it now and how well do you still see? How good is your quality of vision? Did you used to also see 20/15 with glasses? What complications are you experiencing besides disorted astigmatic vision?



>Eye replied:You mean their pupils are larger
>than their full treatment zone, or
>effective optical zone. If they have
>partial treatment within their scotopic pupil
>that's a problem.


Eye, were your pupils larger than the optical zone?

>Many night vision issues are also due
>to higher order aberrations. Keep in
>mind that surface treatments increase aberrations
>25- to 32-fold when going
>from 3 to 7 mm pupil
>sizes, and LASIK increases the aberrations
>28- to 46-fold.


If so, your night vision would be absolutely terriable! Especially if your pupils are very large and the optical zone smaller than that. Speaking relativately, how bad would you consider your night vision? As bad as a nearsighted person whos 20/100 and takes his glasses off?

>http://www.ncbi.nlm.nih.gov/entrez/...st_uids=9932992

>Unless you want increases in aberrations of
>this magnitude, don't have refractive surgery.
>


So everyone would have seriously impaired night vision or even be legally blind at night? How bad would you compare it to 20/xxx wise? This will give me an idea relatively speaking how bad.


Eye, reguarding advances in lasik, look what I found:


The theoretical limit of visual acuity is about 20/5. But current technology, including laser surgery, cannot correct for all of the eye's aberrations. Until recently, it was difficult to detect many of these flaws. With the emergence of new computer modeling approaches and optical technologies, however, researchers speculate that laser surgery will soon be refined to yield 20/10 in most patients. To succeed will require a unique melding of biology and engineering.



"The human optical system is not very good," he explained. "The problem with the human eye is that the optical axis and the visual axis are separated by an angle of about 5° horizontally and vertically by about 1°; this is angle alpha."

This difference makes humans capable of seeing only 40%, at best, of what a diffraction limited optical system could "see" in the same aperture.




"What ophthalmologists don't measure or think about is the optical center of the eye (angle alpha), which is temporal to the pupillary center; this angle is about twice angle kappa, with twice the distortion," Dr. Holladay said. "Today, laser treatments are not being applied to the optical center or the visual axis. Instead we place them on the center of the pupil, which optically is not a good idea."

Every laser used today, he emphasized, during a refractive procedure is centered on the pupil with the patient's eye tilted out 5° and up 1°; the treatment then is not perpendicular or parallel to either axis and ends up on the nasal side of the cornea, which is the reason for so much induced coma. None of the laser manufacturers account for the tilt of the eye.

Dr. Holladay also underscored the need to create prolate corneas. In relation to laser treatments, oblate corneas result from insufficient energy on the periphery of the cornea because the lasers are calibrated on flat surfaces.

"The light rays strike the surface obliquely in the periphery, and—just like a dish antenna—energy is lost and an oblate cornea results," he said. "This shape exaggerates the spherical aberration and is the most significant reason why patients see halos at night."


Eye, you were right after all! You really think theres no chance of HOA's being reduced even if the patient is seeing only 20/40 or worse with glasses before lasik? I did hear wavefront can help a disaster caused by a previous lasik operation.


On the horizon "Diagnostics will see substantial improvements in visual assessment and new contrast sensitivity testing," Dr. Holladay said. "Wavefront will be wonderful. Corneal refractive surgery will move more and more to surface ablation with aspheric treatments on the visual axis, and more physicians will be using topography and wavefront.

Eye, perhaps todays lasers leave some to be desired but in the (near) future there should be breakthrus. Lasik was much riskier with worse outcomes 5, 8, 10 years ago but we have come a long way. Tomorrows lasers will be that much better in everyway.
11/13/2005, 2:50 am Link to this post Send Email to Myope5   Send PM to Myope5
 
Myope5 Profile
Live feed
Blog
Friends
Miscellaneous info

Head Administrator

Registered: 05-2005
Posts: 816
Karma: 8 (+9/-1)
Reply | Quote
Re: todays wavefront lasik isnt yet perfect


Wavefront-guided lasers are not approved to reduce higher order aberrations (HOA) as they have not been shown to consistently and predictably reduce existing HOA (see http://www.usaeyes.org/faq/subjects/HOA_Advisory_Memo.pdf). Yes, HOA can be reduced with wavefront-guided surgery, but not all HOA, every time, and with reliable predictability and consistency. Many studies have shown that as a general rule wavefront-guided ablation increases HOAs at a much lower rate than conventional ablation. So your HOAs will be elevated less with wavefront-guided than with conventional, and some might go down. The reason wavefront is more important in surgery than glasses and contacts is because glasses and contacts tend to not induce HOAs.
11/13/2005, 3:28 am Link to this post Send Email to Myope5   Send PM to Myope5
 
Myope5 Profile
Live feed
Blog
Friends
Miscellaneous info

Head Administrator

Registered: 05-2005
Posts: 816
Karma: 8 (+9/-1)
Reply | Quote
Re: todays wavefront lasik isnt yet perfect


>Hi Ace! I have noticed you are
>beginning to 'see through' all the
>marketing claims and are really getting
>a grasp on the problems inherent
>in refractive surgery.


There is alot of marketing and politics surrounding lasik. We have the freedom of speech to give our opinions of lasik as long as we dont flame anyone. I can see there are still shortcommings in lasik. However we are working on them. lasik in the past was much worse than its today. Lasik in the future very well may further address some shortcommings.


>Believe it or not, there was an
>FDA hearing discussing the increase in
>HOAs by custom wavefront LASIK and
>how this information should be disclosed
>in the patient labeling to the
>public.


That information was never mentioned to me. I just heard it reduces HOAs and makes your cornea more perfect and you see better without glasses. I guess that is true for highly abberated eyes but ive seen lots of people with high BCVA(better than 20/20) complain about decrease in quality and even accuracy in vision. To put it short, the better your BCVA is before lasik, the more you have to lose. The worse your BCVA is before lasik, the less you lose and you may even gain!

>DR. GRIMMETT: Dr. Bradley stated wavefront-guided LASIK
>does not reduce the level of
>higher-order aberrations of the preoperative eye,
>and he also wrote there's no
>way wavefront-guided LASIK can correct higher-order
>aberrations and render super-normal vision.


I am hearing conflicting reports. Some make the claim you can improve one or more lines of BCVA. Do you think it was because of glasses minification? Improper glasses pescription? Improperly made or fitted glasses/contacts?
If it always increases HOA's then your visual quality and accuracy will always go down from your true BCVA. My true BCVA is probably 20/25 but I am not gonna achieve this with -5 glasses. with RGP probably because they dont minify and also they provide a smooth, percise fit over the cornea. Unless wavefront lasik can really remove my HOAs and I end up with less than what I had before lasik, I will see no better than I do with glasses.

>DR. GRIMMETT: Sure. Wavefront-guided LASIK does not
>reduce the level of higher-order aberrations
>of the preoperative eye.

>DR. WEISS: Would that not be confusing
>to someone? Wouldn't that be confusing?
>


its very confusing, especially to me.


>DR. GRIMMETT: Michael Grimmett.It may suggest somehow
>wording in that wasn't it that
>the higher-order aberrations were 20 percent
>higher than the preop eye in
>the wavefront-guided versus what, 80 percent
>was the number?

>PARTICIPANT: Seventy-seven percent.


question for eye, what was your glasses pescription before and what was your BCVA? You mentioned in another post you were seeing a blurry 20/15 for a while but not anymore. Were you able to see 20/15 better with glasses?


>DR. WEISS: In here, is there any
>place saying that LASIK itself increases
>aberrations and that customized corneal ablation
>increases them less than conventional treatment?
>

>DR. GRIMMETT: I think that's the idea.
>


this makes sense. However the word "reduced" is used too liberally. Its reduced compared to conventional lasik but NOT reduced compared to no lasik. I think they should start telling everyone that wavefront lasik will create a reduced amount of extra HOAs vs. conventional instead of just saying "reduced" they need to explain the meaning of "reduced"



>DR. WEISS: So maybe we could put
>that wavefront-guided ablation ??

>DR. GRIMMETT: Conventional LADARVision LASIK increases higher-order
>aberrations by that figure 77 percent
>while wavefront-guided LASIK increases them by
>whatever, 20 percent, whatever the number
>is, or you can say reduces
>them to a 20-percent level, if
>you want to use the word
>"reduces."

>DR. BULLIMORE: I would avoid the term
>"reducing."


Its just so confusing! It reduces HOA's but not in the way many people believe. We should say "increases less"


>DR. WEISS: I would say each of
>them increases it because basically whether
>or not you're treating the preexistent
>or what's induced, the bottom line
>is you still have more aberrations
>than you did when you started
>off.

>DR. GRIMMETT: Well, the intent is telling
>the traffic cop that you're speeding
>less than the other speeders.------------------------------------------------

>Go to FDA.gov and look up the
>approvals for wavefront guided treatements. You
>will see that the FDA states
>that HOAs are NOT reduced.

>You quoted Jack Holliday - here is
>something he said in the current
>issue of the Journal of Refractive
>Surgery:

>" Ablations based on refractive wavefront aberrometry
>alone, without detailed knoweledge of the
>patient's current corneal topography WILL NEVER
>attain the best visual results and
>is the reason wavefront-guided ablations have
>lost much of their luster".

>Unless you have an EXTREMELY aberrated cornea
>it is unlikely that your HOAs
>will be decreased by wavefront treatment.
>We are still searching for ONE
>patient who had normal virgin eyes...
>who experienced a decrease in HOAs
>after wavefront treatment.


There are topographies of people before and after lasik. Some of them are obviously worse but others appear to be better but then I am not an expert at interpreting topographies.


>Ace - you've hit the nail on
>the head! What is really upsettig
>to me is that doctors will
>perform LASIK on patients like you,
>who do not have 'visual quality
>reserve' to play around with.


He just said "we can get you to 20/25"
When he gave me a manual refraction I was kinda just guessing the 20/25 line. I had said "too small, cant see those" then he said try your best so I did. I guess I can partially blame my -5 glasses for minification and making the 20/25 line too small. If I end up plano with lasik then his 20/25 claims are reasonable.


The fact
>that you are not correctable to
>20/20 now may or may not
>be due to HOA's (you should
>go for a thorough exam and
>find out).


I can show you my topographies here:

http://www.asklasikdocs.com/forum/main/3371.html

Feel free to interpret them. I have been told I have irregular astigmastim which cant really be corrected by glasses. Notice the orange colors, this is the steeper, uneven part.


Refractive surgery is riskier
>for you because refractive surgery does
>reduce visual quality and your baseline
>of visual quality is nothigh.


If I have highly abberated eyes, I may not end up worse but it still wont guarantee overcorrection, dry eyes, regression, GASH, etc or still needing glasses anyway.



>My hope is that getting the word
>out will protect the 'visual reserves'
>of patients like you.



What do you think of intacs then? Perhaps I am better suited for those?
11/14/2005, 3:40 am Link to this post Send Email to Myope5   Send PM to Myope5
 
Myope5 Profile
Live feed
Blog
Friends
Miscellaneous info

Head Administrator

Registered: 05-2005
Posts: 816
Karma: 8 (+9/-1)
Reply | Quote
Re: todays wavefront lasik isnt yet perfect


converstation I had with a dr. in reguards to lasering low myopes



>I appreciate your comments - but you
>are missing a few key points
>that you need to ask prior
>to making blanket statements about patients.
>The first key question is:
>How old are you?


I am 23 and my accomodation isnt very good. How much accomodation is someone my age supposed to have? I have measured my accomodation at +2.5 diopters each eye seperately and about +4 with both eyes if I really focus and cross them.


>Patients who are 22 years old and
>-2 can benefit greatly from refractive
>surgery. They are 20 years
>away from Presbyopia - and the
>can be a little over-corrected and
>still se great.


It depends on the person. Some start developing presbyopia earlier. We dont know the age or how much accomodation they have when they post asking for lasik to treat their mild myopia. I have interest in intacs because it will leave me around -2 diopters of myopia which will allow me to be less dependant on glasses and yet be able to read and use the computer without reading glasses.


>Finally - the results of treatment for
>a patient with -2 diopters of
>myopia is better than for a
>patient with -10 diopters - so
>we expect an extremely high success
>rate for these patients.


you are very correct. However it is just my opinion that surgury is "not worth it" for low pescriptions. I would love to be a -2 then there would be alot I can do without glasses and I would see pretty well without glasses. In fact I wear glasses that undercorrect me by -1.5 to -2 diopters around the house and for the computer because most of the seeing I do around the house is only half to two meters away and its easier on the eyes not to have to constantly accomodate for close range.


>As a note - one of my
>closest friends (who is a family
>member - my cousin) underwent lASEK
>with me a year ago.


Some people have told me doctors and their family usually dont get lasik because of the risks. This isnt always true and youve stated your point. What was your own pescription before lasek and how well do you see post lasik?


 He
>was 24 years old at the
>time, and had 1.5 diopters of
>myopia. He was unable to
>wear contacts and hated glasses.

Did he have any conditions that prevented him from wearing contacts? I dont seem to be able to tolerate contacts well either. People have suggested different brands, ive tried several and they all more or less begin to dry and irritate my eyes. I dont mind glasses too much with my seditary life but want to be less dependant still.


>He loves to play softball (We
>have an evening softball league) and
>he could not properly judge flyballs
>without glasses (but he never wore
>them because he hated wearing them).
>So for my cousin - he
>has consistently stated that he loves
>his vision following surgery- and it
>was one of the greatest things
>he has done.


Thats great. His lifestyle is one where he did indeed benefit from lasik despite having low myopia.


>Again - there are risks with any
>surgery - and my cousin understood
>that there were risks. But
>since surgery he has fantastic quality
>of vision both during the day
>and at night.



how well did he see without glasses? how well is he seeing now after lasek? Thanks for your time to reply to my questions. I hope whatever I said didnt offend anyone. I often express my opinion but I dont outright say "omg dont do lasik itll make ya go blind" but I point out the risks and comment based on their pescription, cornea thickness, pupil size, etc.
11/14/2005, 6:35 am Link to this post Send Email to Myope5   Send PM to Myope5
 
Myope5 Profile
Live feed
Blog
Friends
Miscellaneous info

Head Administrator

Registered: 05-2005
Posts: 816
Karma: 8 (+9/-1)
Reply | Quote
Re: todays wavefront lasik isnt yet perfect


questions for doctors and anyone in the know.


I have several questions about intacs:


1. My pupils are rather large. Is there a pupil size limit for intacs? Lasek?
2. How much is the intacs procedure? lasek?
3. I would of thought intacs would be more popular for low to moderate myopia because of the following advantages:

a. can be removed or extracted anytime for any reason. Lasik is irreversable.
b. does not remove or ablate any cornea
c. does not touch your center vision, just the sides
d. doesnt severe or destroy any nerves in the cornea(see dry eyes)
e. viturually no chance of overcorrection for moderate myopes

4. I have -4.5(right) -5(left) of moderate myopia with about -.5 astigmastim. I should end up around minus a couple diopters which would greatly reduce my dependancy on glasses and yet let me see well enough from near and intermediate without reading glasses.
5. Does intacs remove high order abberations and irregular astigmastim? Could it help improve my BCVA from 20/30 to 20/25 or even better?


I feel that intacs may be the better option than lasik because of its removability, greatly reduced chance of overcorrection(can be removed for thinner ones) and if I am not satisfied or experience visual anormalities, they can be extracted. There are several guys posting on asklasikdocs and elsewhere stating the dangers of lasik(which I already know most of the risks) but I was supprised to hear all lasik, even wavefront increases high order abberations by 20% and that lasik ruins the vision of all eyes in quality and also sometimes accuracy. I know ill be seeing much better after lasik than without glasses but will I see as well as I do with glasses, especially at night? Accroding to some, its usually not unless you have high myopia and/or high astigmastim and highly abberated corneas. The infomation some provide is debatable id say. Thanks for your time reading and replying emoticon
11/14/2005, 7:49 am Link to this post Send Email to Myope5   Send PM to Myope5
 
Myope5 Profile
Live feed
Blog
Friends
Miscellaneous info

Head Administrator

Registered: 05-2005
Posts: 816
Karma: 8 (+9/-1)
Reply | Quote
Re: todays wavefront lasik isnt yet perfect


just got a response from him. Hes a great doctor and great guy!


Thank you so much for emailing me.
        I hope you understand why I have to Ban Bill/Eye/Krrrrr from the Bulletin board. Their approach is mean and nasty, and they twist the truth all the time. They cite papers - and use information from those papers in inappropriate ways. They also ignore any reports or evidence that does not jive with their goal of bashing LASIK
        Case in points;
           1. 29% of refractive surgeons have had LASIK. Their response - they had it a while ago. But they are wrong. I know plenty of doctors who have waited until now - because technology is better
        ` 2. They like to talk about higher order aberrations - but they do not understand them. I do not have all day (unfortunately) to find every citation to immediately answer every piece
           First - Steve Schallhorn has shown in his analysis of Navy fighter pilots that certain forms of higher order aberrations actually enhance depth of field and provide better quality of vision. I do not have his article - but try googling him - and use fighter pilot and his name and perhaps aberrations
           As well - I perform surface ablation - and there are studies (which I need to find) that show that with wavefront - there is no increase in higher order aberrations.
           And patient perception - I have plenty of patients that see better after surgery than they have ever seen prior to refractive surgery

        Anyway - I have to see patients right now - I am happy to explain my decision further if you need it

As for your answer

1. Pupil size is important for Intacs
2. Intacs costs $3400 per eye. The big difference is the facility fee and the fee for the Intacs. Overall - that adds up to $1400 per eye.
3. For low myopia - the visual results are fantastic with surface ablation. Intacs are also more expensive. Plus many surgeons are not Intacs certified
        Finally - Intacs bring vision into the Ballpark - but they are not perfect at getting 20/15. This is because there are only a few sizes - that have to treat a wide range of viison.
4. I agree Intacs are reversible. But surface ablation for low myopia in general provides fantastic results - and I can not think of any patients of mine that would want to have their procedure reversed.
        Remember - surface ablation provides an excellent visual results and their is no flap - so no striae, flap complications, etc
        Also - Intacs have risks - infection, etc just like suface. The risk of infection would be similar
5. The nerves regenerate with surface ablation - and clinically patients do really well. There is no clinical evidence of permanent nerve loss with surface ablation. Patients get a return of their corneal sensitivity to baseline by 3 months with surface ablation


PS - you should really get examined - 20/30 vision best corrected is a concern - and loss of reading is also a concern. It is not normal to become presbyopic prior to age 40. I have never seen this happen to a person with normal eyes before - so it is concerning as well when you mentioned that






11/15/2005, 3:40 am Link to this post Send Email to Myope5   Send PM to Myope5
 
Myope5 Profile
Live feed
Blog
Friends
Miscellaneous info

Head Administrator

Registered: 05-2005
Posts: 816
Karma: 8 (+9/-1)
Reply | Quote
Re: todays wavefront lasik isnt yet perfect


,
        Thank you so much for emailing me.

you are welcome!

        I hope you understand why I have to Ban Bill/Eye/Krrrrr from the Bulletin board. Their approach is mean and nasty, and they twist the truth all the time. They cite papers - and use information from those papers in inappropriate ways. They also ignore any reports or evidence that does not jive with their goal of bashing LASIK

I agree. You kindly linked them to the approperate forum. The asklasikdocs forum isnt the right forum for the kind of stuff they post.
        Case in points;
           1. 29% of refractive surgeons have had LASIK. Their response - they had it a while ago. But they are wrong. I know plenty of doctors who have waited until now - because technology is better
Doctors are getting lasik even today and they know the risks extremely well. If even doctors and surgeons are getting lasik, then its quite safe with very low risks. Some people think lasik ruins all eyes but this isnt true unless theres a complication and most complications get resolved anyway.
        ` 2. They like to talk about higher order aberrations - but they do not understand them. I do not have all day (unfortunately) to find every citation to immediately answer every piece
           First - Steve Schallhorn has shown in his analysis of Navy fighter pilots that certain forms of higher order aberrations actually enhance depth of field and provide better quality of vision. I do not have his article - but try googling him - and use fighter pilot and his name and perhaps aberrations
I have heard a little about this. HOAs can have their benefits, but they are often potrayed in a negetive way, especially concerning night vision.
           As well - I perform surface ablation - and there are studies (which I need to find) that show that with wavefront - there is no increase in higher order aberrations.
Surface ablation is superior to getting a flap in many ways. I for one would never want a flap. How high a pescription can surface ablation be used on? I read its FDA approved to -6 for wavefront and surface. Do you think the flap lasik will fall out of favor soon?
           And patient perception - I have plenty of patients that see better after surgery than they have ever seen prior to refractive surgery
makes sense. Glasses and contacts block some light and they cause glare and starbursts, especially with dirty glasses lenses. I did hear to expect at best equal visual accuracy after lasik as what you were seeing with glasses. Meaning if I see 20/30 with glasses, the best I can expect is 20/30 with todays laseks.

        Anyway - I have to see patients right now - I am happy to explain my decision further if you need it

I would love to hear your decision that you got lasek last year. what was your pescription before and BCVA? What is it now and UCVA?

As for your answer

1. Pupil size is important for Intacs

what is the upper limit?
2. Intacs costs $3400 per eye. The big difference is the facility fee and the fee for the Intacs. Overall - that adds up to $1400 per eye.
thanks for the info!
3. For low myopia - the visual results are fantastic with surface ablation. Intacs are also more expensive. Plus many surgeons are not Intacs certified
This makes sense. If someone came in and asked for intacs or lasek, which would you reccomend?
        Finally - Intacs bring vision into the Ballpark - but they are not perfect at getting 20/15. This is because there are only a few sizes - that have to treat a wide range of viison.
Some people fall in the range intacs can treat. Although I have more myopia than intacs can correct, I can become less myopic and less dependant on glasses yet have enough myopia not to need reading glasses. Ill probably keep my 20/30 BCVA with glasses but improve uncorrected vision to the point I need glasses much less and still not need reading glasses.
4. I agree Intacs are reversible. But surface ablation for low myopia in general provides fantastic results - and I can not think of any patients of mine that would want to have their procedure reversed.
I dont know how ill react to intacs but if im not happy with them, it can be extracted. with lasek whatever the outcome I get, ill have to live with it.
        Remember - surface ablation provides an excellent visual results and their is no flap - so no striae, flap complications, etc
        Also - Intacs have risks - infection, etc just like suface. The risk of infection would be similar
The risks for intacs and lasek are comparable with pros and cons for each. I like the pros that intacs give over lasek such as keeping a more prolate cornea, their removability, greatly reduced risk of overcorrection, not removing any cornea, etc.
5. The nerves regenerate with surface ablation - and clinically patients do really well. There is no clinical evidence of permanent nerve loss with surface ablation. Patients get a return of their corneal sensitivity to baseline by 3 months with surface ablation
so dry eyes is not a concern unlike in lasik?


PS - you should really get examined - 20/30 vision best corrected is a concern - and loss of reading is also a concern. It is not normal to become presbyopic prior to age 40. I have never seen this happen to a person with normal eyes before - so it is concerning as well when you mentioned that

When my dad has to go down to Miami, I will come along with him and be glad to see you and your assisants for a comphrensive evaluation. If its determined my 20/30 BCVA is due to irregular astigmastim and HOAs, can anything be done? If not, can it in the future? My presbyopia is what id consider mild. My nearpoint is 20/40 with full power glasses but 20/25 with weaker glasses. If I hold material half meter away, its clear. I can see clear from much closer with reduced minus power. Id say I have about +2.5 diopters of accomodation in each eye, how much accomodation is a 23 year old supposed to have? one more thing, you mentioned the risks of contacts, would you say sleeping in your contacts nightly for years is worse than lasek?

my reply to him
11/15/2005, 4:11 am Link to this post Send Email to Myope5   Send PM to Myope5
 
Myope5 Profile
Live feed
Blog
Friends
Miscellaneous info

Head Administrator

Registered: 05-2005
Posts: 816
Karma: 8 (+9/-1)
Reply | Quote
Re: todays wavefront lasik isnt yet perfect


Jim Schwiegerling, PhD, is turning to optics technology used in telescopes to develop refractive surgery methods that could improve vision beyond the standard 20/20.
That is great! However, todays lasers claim the percent who get 20/20 to be anywhere from 80% to over 95% but I dont believe this because many people dont achieve 20/20 with corrective lenses. Eye has pointed out that such studies are biased in they convinently leave out a large percent of the sample, like 70% were left out and he says because those 70% didnt achieve the vision expected. A lasik employee posted on another forum that he sees the 20/20 rate at around 50% after 1-3 years and it may be even less for severe myopia(-6 to -9.75)

 Dr. Schwiegerling, assistant professor with a joint appointment at the Department of Ophthalmology and the Optical Sciences Center, leads one of several groups around the country using light-measuring technology employed by telescopes to measure aberrations of the eye that limit visual acuity. These measurements would improve the efficiency of refractive laser surgery, resulting in much sharper vision.
I give credit for todays lasers that are starting to get there. lasers of the past were quite inadequate, often giving you vision worse than with corrective lenses before. They created more HOAs. Todays lasers create "reduced" HOAs

When light travels through the atmosphere, it becomes distorted by atmospheric turbulence. Astronomers are able to correct the telescope image blurriness by using lasers and computers to measure the amount of distortion. The measurements are used to prompt a deformable mirror to quickly alter the incoming light wave front. This adjustment restores a sharp image of the object in the sky.

When light enters the eye through the pupil and travels through the orb to the retina, it is distorted by natural aberrations inherent to the eye. These minute imperfections distort the light, causing blurry vision.
some people have more HOAs then others. If we rule out occular pathalogy, especially common in very high myopes, one should on average achieve a 20/20 true BCVA, compenstating for spectacle minification of course. HOAs on the cornea may dictate ones BCVA be it 20/15, 20/20, 20/25, 20/30 or even worse.

Utilizing the technology from telescopes, Dr. Schwiegerling is able to measure light reflected from the retina and use these measurements to plot a wave-front image that maps all the aberrations of the eye. Having this wave-front image could make it possible to customize refractive surgery to perfectly correct for all the aberrations. The outcome could be improved visual acuity beyond 20/20, as well in seeing low-contrast and dim objects. Dr. Schwiegerling said that it theoretically is possible to achieve acuity between 20/5 and 20/8.
we are still quite a ways from it. I heard it wont be possible in the near future. I however did hear a goal of 20/10 by the year 2010 but this remains to be seen. There supposedly are 34 challenges to be met before we can reach the VA of the retina's limit itself.

Dr. Schwiegerling’s research will be critical as a second generation of excimer lasers – currently used in photorefractive keratotomy (PRK) and laser in situ keratomileusis (LASIK) surgeries – are being developed. Existing excimer lasers may correct most, but not all, of a patient’s refractive error. Moreover, laser eye surgery creates new aberrations as a tradeoff for 20/20 eyesight.
tradational lasik 80%, wavefront 20% more HOAs on average. In many cases, this results in loss of BCVA. I hear claims that all eyes are damaged by lasik and visual quality diminishes with the exception of highly abberated eyes where theres no change or even a slight improvement.

"Our goal is to optimize the result of refractive surgery," Dr. Schwiegerling said. "Right now, the surgery allows people to see as well without their glasses as they do with. We want people seeing better than 20/20 after surgery."
The best you can expect to see is as well as you did with your glasses and in many cases, worse. Youd need to end up plano without too many induced HOAs. Even if one achieves 20/20, theres always the issue of regression at any time, sometimes even years later. I know more than a few who regressed and were quite upset. Some paid and did lasik all over, others just left things be. Remember, lasik is surgury to reduce dependancy on glasses rather than guarantee perfect vision


my comments will be in bold, see above!
11/16/2005, 5:34 am Link to this post Send Email to Myope5   Send PM to Myope5
 


Add a reply

Page:  1  2  3 





You are not logged in (login)