Exposing the LASIK Scam

Help understanding my aberrometry results
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Author:  TotallyScrewed [ Mon Feb 13, 2006 9:20 pm ]
Post subject:  Help understanding my aberrometry results

Despite the huge bucks that they charge for consults, the refractive surgeons I have seen refuse to comment on the significance of my higher order aberrations. I have no idea how my aberration profile compares to others who are suffering vision loss after LASIK like I am. My results are as follows:

RMS wavefront error in microns
Left eye: Pupil size 7.0 mm
Total RMS error: 6.62 micorns
Higher Order 2.98 microns
Coma 1.67 microns
Spherical 1.49 microns

Right eye: Pupil size 6.7 mm
Total RMS error: 6.25 microns
Higher Order Aberrations: 2.35 microns
Coma 0.86 microns
Spherical 0.74 microns

I am wondering how this aberration profile compares to others whose lives have been devastated by this surgery. I know that RMS error varies with pupil size, but does anyone have any reference to mean higher order RMS values in virgin eyes?

In addition to a loss of mulitple lines of best corrected vision, I also suffer from ghosting, starbursts, glare, and severe contrast sensitivity loss

My surgeon considers me a successful outcome.

Author:  Eye [ Tue Feb 14, 2006 1:14 am ]
Post subject:  Welcome to the flap, Totally

Say, totally. One important piece of information is the pupil size used to obtain the wavefront measurements. Some aberrometers can be set to read at various pupil sizes. The crummy VISX instruments only measure at 6mm I believe.

The measurement you WANT is the measurement taken at your maximum dark-adapted pupil size, called your scotopic pupil size.

About those aberrations. They are huge. If these values reflect a 6mm reading you really have some horrendous vision in the dark.

I have read that the smallest amount of HOA recorded in virgin eyes is about .07 microns.

People with large pupils often start complaining with about 0.5 microns of HOA after surgery.

I bet that coma in your left eye really drives you crazy.

Have you tried the pinhole test to see if that restores your BCVA? If you are looking out of a tiny pinhole you are not visualizing most of the induced aberrations. Helps rule out other problems in the visual system.

How far out are you from surgery?
What was your pre-op refraction?
Have you tried RGP's?

Do you have dry eye?

So sorry all this happened to you. Keep us posted on your situation.

Author:  Broken Eyes [ Tue Feb 14, 2006 1:47 am ]
Post subject: 

My goodness! Your vision is worse than mine! My numbers were taken at my scotopic pupil diameter of 8 mm. How large are your pupils in the dark?

Here are my numbers:

Left eye:
Defocus 7.33
Astigmatism 1.05
Coma 1.09
Spherical Aberration 1.82
Other .59
Total RMS 7.73
Higher Order 2.20

Right eye:
Defocus 7.69
Astigmatism .60
Coma .55
Spherical Aberration 1.79
Other .65
Total RMS 7.96
Higher Order 1.98

Here are some important points. Your wavefront should be taken at your scotopic pupil diameter. A scan taken at any diameter smaller than your scotopic pupil diameter is meaningless -- like weighing a 200 lbs. woman on a scale that only goes up to 150 lbs.

The industry and LASIK surgeons like to fool the public, patients and a jury by reporting aberrations at 6 mm instead of the patient's scotopic pupil diameter. Never fall for this trick!

Aberrometers vary on the way they gather the information, so the data is not consistent across different aberrometers and the wavefront will change slightly each time a scan is taken (reproducibility). My numbers are from the LADARWave device. Some aberrometers cannot even measure a large pupil. Which aberrometer was used for your scans?

The two most common higher order aberrations are spherical aberration and coma. Coma is typically a result of a decentered ablation. Spherical is a result of an effective optical zone that is too small. All patients have some induced spherical aberrations because lasers do not fully correct the refractive error across the entire diameter of the treatment -- this is known as the "cosine effect" or the "radial compensation function" as described by Dr. Jack Holladay, and it happens because lasers lose efficiency on the slope of the cornea. Most LASIK patients say they see great outdoors in bright sunlight with a 2 - 3 mm pupil, but the story changes as the sun goes down. Patients with unusually large pupils (7 mm or larger) and patients with high myopia are most affected by spherical aberrations and all higher order aberrations.

I read an article that said that said significant higher order aberrations is defined as RMS greater than 0.1 microns. I would say that we meet that criteria!!! I have 20 times what that article considers "significant higher order aberrations", and yours is even higher. http://www.escrs.org/Publications/Eurot ... dedPRK.pdf

Your surgeon considers you a successful outcome? What a moron!!

Just curious, what was your pre-op refractive error, and what is it now? What laser was used? How large was the optical zone and how large was the blend zone?

Author:  TotallyScrewed [ Sat Feb 18, 2006 1:33 am ]
Post subject: 

EYE and BrokenEyes

Thank you for sharing your results with me. I have seen many refractive surgeons in consultation since my bad LASIK outcome, but few are forthcoming in useful ways. Thank you for your efforts to bring the truth forward.

In response to your questions. I was a moderate myope preop with a prescription of -4.75OU with no astigmatism. Preoperatively, I corrected to 20/20 and 20/15 with glasses. My surgery was performed several years ago on LADARVISION 4000 with autotracker.

I did not have dry eye preop, but I now have severe dry eye. My Shirmer's test is less than 1mm at 5 minutes and my TBUT is instantaneous. My fluorescein clearance test is incompete at 30 minutes. I have tried RGP's, but I have been unable to tolerate them due to the constantly burning dry eye. I have severe GASH and cannot drive at night. You are correct about my left eye. It really gives me problems. I have double vision in my left eye, and experience frequent headaches both behind my eye, as well as in the back of my head. The most useful information I received post op came not from a refractive surgeon, but from a vision specialist (OD). He did extensive tests on me that determined that I only see out of one eye at a time. (Thank God!). Most of the time, I am totally supressing my left eye image. I notice the double vision most when I drink a cup of coffee. When the coffee cup nears my mouth, it blocks the vision in my right eye, and I see a double image out of the left. WHen I put the coffee back down, the ghosting image is much less apparent.

My high contrast uncorrected vision now is a distorted 20/60 OS and a distorted 20/40OD, my dim light vision is clearly much worse . Glasses do nothing to improve my vision.

THe fifth or sixth refractive surgeon that I saw in consultation post-op did admit to me (rather reluctantly) that I did not receive a transition zone with the LADARVISION.

If I have any words of advice for prospective refractive surgery patients it is this: Expect to be abandoned if you have complications. Refractive surgery is the only branch of "medicine" that allows patient abandonment as part of the standard of care.

Author:  ElviraTexan [ Sat Feb 18, 2006 4:55 am ]
Post subject: 

Totally Screwed:
I also have severe dry eye, 2 and 3 last December, 2005, he did not check my TBUT. I also have double vision in my left eye but as ghosting type and see nothing clearly at any distance. I also experience frequent headaches behind both my eyes as well as in the back of my head with constantly burning, painful eyes.
What do you take for the pain? Does it work? Sounds like it doesn't. Presurgery both my eyes corrected to 20/15 and I was not told. My surgery was done June 2004 with the VISX4. MY dim light vision is terrible, where before I could see extremely well in the dark. Basically all I know is that I no longer correct to 20/20 even with glasses. I also have sticky, gooey, gummy tears that make my lids stick together and in the morning the light and breeze hurt my eyes. I also tried soft moisture retaining contact lenses but could not stand the pain they caused.
How do you manage? Please see my web site at www.dr.doka.com. for my complete story. Eye has helped me so much, but I just do not function anymore. Between the pain, the crud, the burning, I do not care anymore. I just do not function. I no longer work, do not care about my house or myself. It sounds like you drive during the day, are you still able to work? Basically, how do you manage? There are days that I am so attempted to end it all and unfortunately I did try already.There are times that I wonder how I got myself into this never ending nightmare and I cannot get out of it. How were your able to get your aberration profile? I am looking for a ray of hope. Somedays, I just want to completely end it, even though it is against everything I believe. Somedays, I just go from moment to moment.
How have you managed for several years? Because sometimes (many) times I do not even want to go on for 5 more minutes much less think of months or years. I literally do not want to go out for anything and my husband is very depressed and has started going out on his own when prior to surgery we went everywhere together. This refractive surgery has totally ruined my life. How have you done it?
Elvira Texan

Author:  Scientist [ Sat Feb 18, 2006 10:31 pm ]
Post subject:  To 'TotallyScrewed'

It's not easy to figure out what you can do to make yourself feel better and obtain the best possible vision and comfort after a refractive surgery disaster. Especially when surgeons won't give a straight answer about poor outcomes! Patients struggle to obtain the help that they need. A refractive surgeon who legally blinded his patient in BOTH eyes actually wrote 'patient doing well' in this patient's charts. No, I am NOT joking. I suppose if you're not actually legally blind after surgery they ramp up the evaluation to state that they are 'pleased with the outcome'.

TotallyScrewed, I don't know how many experts you have seen, but if you haven't gone to someone really good - a world class rehab specialist (careful, many docs will claim they are rehab specialists) perhaps you should.

What puzzles me is how bad your daytime BCVA is. This suggests that you have something going on with your central cornea (spherical aberration is a peripheral thing, worsened in your case by not getting a blend zone) or perhaps your retina was damaged by the suction ring during the procedure?

Even people WITH a blend get spherical aberration (I have a blend and my GASH is horrible - VISX S4 platform).

TotallyScrewed, you should consider going to a doctor who will measure your higher order aberrations starting from 3-4 mm all the way out to 7 (if that is indeed a proper measurement of your scotopic pupil). Did you ever have any DLK after surgery that could have left you with haze? Does your vision 'clear' with eyeddrops? Dry eye can cause cloudy vision, and you are parched. I need to go through your old posts and see if you mentioned having punctal plugs. If you don't have them maybe you could inquire about plugs, or even consider having your lower ducts cauterized - an option. Do you mind me asking your age and gender? Typically dry eye is associated with older age and female gender, but of course LASIK causes dry eye to some degree (from mild to debilitating) in everyone.

Usually people who have had a bad LASIK outcome and have learned ANYTHING AT ALL about refractive surgery would never suggest having a bad outcome retreated again with a laser. However your vision is substantially reduced that having a retreatment by one of the smartest and most conservative surgeons may be an option IF your residual stromal thickness (RST) or tissue thickness under the flap is well over 300 microns! This is something that you would need to think long and hard about, research, and plan carefully.

The problem with wavefront retreatment is that they will take a wavefront measurment through your flap, then lift your flap to correct underneath. It would be essential for you to have an Artemis scan to determine if your flap itself is wavy/irregular, and how wrinkled it is. My flaps are full of striae which contributes to MY daytime visual quality loss (and also worsens nighttime problems). Treating for a problem within the flap, or a problem due to the way the flap healed by lasering *under* the flap and then putting the flap back down... well - just imagine how bad that would be. With an Artemis scan (which is essentially an ultrasound of the anterior portion of the eye) you will see thickness of all the layers of your cornea with a 1 micron accuracy. They're pretty amazing photographs and essential, I think, for anyone planning a retreatment.

Doctors tend not to inform patients well about laser-induced aberrations, let alone that cutting a flap and putting it back down WITH NO LASERING induces aberrations. It turns my stomach that a medical doctor is willing do this to a healthy eye for cash.

Were you TotallyScrewed from the moment you had LASIK or did your vision deteriorate over time? Has your vision been stable/unstable with in the past year?

The fact that your total RMS error is substantially higher than your total higher order RMS error suggests that you WOULD, like BrokenEyes, benefit substantially from corrective lenses - so I''m surprised to hear that glasses do nothing to improve your vision. Have you tried visiting a good OPTOMETRIST who does refractions for a living to be fit for glasses rather than relying on a technician who works for a refractive surgeon to determine your prescription?

What did your original surgeon, the 'prince' who abandoned your case... say to you about the cause of your loss of vision?

FYI, I was abandoned by my surgeon too. He sent me a letter telling me my next appointment was canceled... with the lame excuse that trust was an important part of the doctor-patient relationship. I brought my mother with me to one of my visits with this surgeon, and we overheard him mocking me in the next room for doing so. Such unprofessional behavior! What's to trust? My surgeon was Dr. Terry Kim, MD of Duke University - what kind of person do you think he is?

Who was your surgeon?

Author:  Eye [ Sat Feb 18, 2006 11:34 pm ]
Post subject:  Most don't have pupils small enough to safely avoid GASH

Most people don't have pupils small enough to assure a successful night vision outcome with the optical zone sizes approved by the FDA! If you need an optical zone to be 1mm larger than your dark-adapted pupil, that means nobody with pupils over 5.5mm can have FDA-approved LASIK on the VISX and Alcon platforms, which are FDA approved for an optical zone of only 6.5mm.

Keep in mind also that the *effective* optical zone always ends up smaller than the planned (programmed) optical zone. So that 1mm 'cushion' isn't really all that safe! If you have pre-op astigmatism and they attempt to correct for that with the laser, it makes your zone even smaller on one axis because the zone must be oval to correct for astigmatism. So what are we talking about for a safe dark-adapted pupil size to reliably avoid GASH... 5mm? 4.5mm???

'Totally' didn't even get a blend for his 6.5-7mm pupils - that is a CRIME!

Author:  TotallyScrewed [ Sun Feb 19, 2006 9:42 pm ]
Post subject:  Re: To 'TotallyScrewed'

Scientist wrote:
TotallyScrewed, I don't know how many experts you have seen, but if you haven't gone to someone really good - a world class rehab specialist (careful, many docs will claim they are rehab specialists) perhaps you should.

Who do you think is a very good rehab specialist? I have done my share of doctor shopping after LASIK, and I have yet to be impressed by anyone that I have met.

What puzzles me is how bad your daytime BCVA is. This suggests that you have something going on with your central cornea (spherical aberration is a peripheral thing, worsened in your case by not getting a blend zone) or perhaps your retina was damaged by the suction ring during the procedure?

Your vision is substantially reduced that having a retreatment by one of the smartest and most conservative surgeons may be an option

I did have a vision potentiometer test which revealed an acuity of 20/20 OU, so my problems do not appear to be retinal (although I have a ton of floaters). Outside of ongoing RGP rehab efforts (severe dry eyes making tolerance next to impossible), I have all but given up on any thoughts of a surgical solution. I just don't trust refractive surgeons anymore.

A "conservative refractive surgeon" is an oymoron. Real doctors take a Hippocratic Oath to "Do No Harm." Refractive surgeons systematically harm with impunity everyone that they touch!

I think that you are right about the Artemis scan. I probably should get one just for diagnostic purposes. My vision has not been stable, and is still regressing, especially in my left eye. Post operatively I was overcorrected to +2.25 (a hell in itself), but now my left eye is plano to minus 0.25 by autorefraction. GLasses do noting to improve the vision in my left eye. I do have a small amount of residual refractive error in my right eye (-1.0), but the residual myopia is helpful for me as I am now presbyopic (49 and male). My pachymetry readings have steadily been increasing in both of my eyes over the years, but my ophthamologist does not have a good explanation as to why this is happening. I do have a 2mm decentered ablation in my left eye. So much for the autotracker, huh?

I believe that severe dry eye contributes substantially to my visual problems. Eyedrops don't really take away my eye pain, and the vision improvement that I get from them is only transient. I have had an assortment of punctal plugs, but even with them the burning persists. I hate the thought of having my puncta permanently cauterized, but at this point in time, I am desperate. I do not recommend Dr Maskin. I saw him and found him arrogant, narcissistic, and downright avaricious. He should be deeply ashamed for the obscene prices that he charges. Dr Tseng is a much better choice, and far less expensive.

I only have a 5mm optical zone in both my eyes, yet the Colvgard pupillometer measures my dark adapted pupils at 8mm.

Author:  Broken Eyes [ Mon Feb 20, 2006 1:11 am ]
Post subject:  Re: To 'TotallyScrewed'

Scientist wrote:
The fact that your total RMS error is substantially higher than your total higher order RMS error suggests that you WOULD, like BrokenEyes, benefit substantially from corrective lenses - so I''m surprised to hear that glasses do nothing to improve your vision.

For clarification, glasses improve my acuity, but not my vision quality. My visual quality with glasses or contacts is terrible -- massive aberrations. Glasses or contacts get me from Point A to Point B in the daylight.

Author:  TotallyScrewed [ Mon Feb 20, 2006 1:45 am ]
Post subject:  Re: To 'TotallyScrewed'

Scientist wrote:
The fact that your total RMS error is substantially higher than your total higher order RMS error suggests that you WOULD, like BrokenEyes, benefit substantially from corrective lenses - so I''m surprised to hear that glasses do nothing to improve your vision.

At the time my aberrometry was performed two years or so ago, I was autorefracting in my left eye at +1.25 with -1.50 of cylinder. Now that I have regressed to plano in that eye, I imagine that my total RMS error in that eye is now predominately higher order. Does anyone know how RMS error and diopters correlate with respect to lower order aberrations, that is, for each diopter of myopia or hyperopia, what is the average RMS second order error?

Author:  Scientist [ Mon Feb 20, 2006 2:30 am ]
Post subject:  Total RMS error in diopters

Go pull out your wavescan and look for these numbers:

Your 'effective blur' is the contribution of both your lower and higher order aberrations, and is reported in diopters. You should also see the contribution of higher order aberrations expressed as a percentage of the total effective blur. So it's easy to figure out how many 'diopters' your total higher order RMS would represent.

Author:  Broken Eyes [ Mon Feb 20, 2006 1:54 pm ]
Post subject: 

Here's a formula to convert RMS to diopters:

http://research.opt.indiana.edu/library ... dLens.html

Scroll down to this paragraph:

"To judge the clinical significance of these results, it is helpful to convert from microns of RMS error to diopters of equivalent defocus. Equivalent defocus is defined as the amount of ordinary defocus needed to produce the same RMS wavefront error that is produced by one or more higher-order aberrations. It is computed using the formula..."

The formula is actually a picture. I can't figure out how to copy and paste the picture here.

Author:  avoidlasik [ Sun Feb 26, 2006 6:09 am ]
Post subject:  I want to learn more

Id love to get a potentiometer test myself. This bypasses all aberrations and errors and tests what the retina itself is capable of. I read that a healthy retina is capable of 20/6(some say even better) to 20/10 vision.
Id also like to know more about RMS. I never had lasik but only correct to 20/30(left) and 20/40(right) with glasses. I believe the irregular astigmastim in the right eye is responsable in addition to a large % of high order aberrations. The quality of vision in my better left eye is fine(I dont know what perfect is like as I never saw 20/20 so I have no reference to that) but my right eye definately isnt as good as the left. My quality of vision probably isnt as bad as lasik eyes when I looked at simulators but I wonder if I can get glasses thatll improve the quality of my virgin eyes.

Author:  Bill [ Sun Oct 28, 2007 7:10 pm ]
Post subject: 


Review of Ophthalmology
Vol. No: 14:02 Issue: 2/1/2007

?The people who have the most higher-order aberrations prior to surgery?for whatever reason?are the people who benefit the most from custom ablation,? he observes, noting that virgin corneas seldom have significant higher-order aberrations beyond spherical aberration and coma. ?If someone has about 0.2 ?m of higher-order RMS error before surgery, that person has such a good optical system that when we make changes with the laser, he may get a little worse. However, if you?re treating someone who was -6 or -7 D with a diopter of sphere and additional astigmatism, he?ll be very happy, as long as the higher-order RMS error is still under 0.4 or 0.5 microns. He?ll be much better off than he was before.?

Author:  Broken Eyes [ Sun Nov 04, 2007 7:15 pm ]
Post subject: 

http://voi.opt.uh.edu/VOI/WavefrontCong ... iation.pdf

This link has a conversion formula for microns of RMS error to equivalent defocus.

It states:

For a 6mm pupil, a red dioptric scale at the top of this graph can be constructed simply by multipying RMS error by 0.77.

I found another book excerpt that said:

.16 um spherical aberration = .125 D equivalent defocus

These two are basically the same. For simplicity's sake, take the HOA RMS and multiply by .77 to determine the equivalent defocus.

It is important to remember that 1 diopter of a higher-order aberration does not have exactly the same visual effect as 1 diopter of defocus. Indeed, the same could be said of astigmatism. I D of astigmatism does not have exactly the same effect as 1D of defocus, yet the use of a common metric helps us judge their relative importance. In this same way, the concept of equivalent defocus allows us to compare the order of magnitude of different kinds of aberrations and judge their clinical significance.

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