Do i have post LASIK ectasia?

hello,

in 2003 i had on both eyes a microkeratome (flap size 180 with hansatome microkeratome) LASIK surgery (both eyes -2,5 myopia). the result was for 4 years great. after 4 years my eyes (in particular my left eye) went bader and bader. with glasses my vision is not really good. only hard contactlenses help to have a good vision.

i have orbscan images pre and post op. can somebody of you look at them please? i'm afraid it could be an ectasia Frown my doctor says no, but i dont't like the posterior float orbscan images of my eyes. i think it looks strange. i have also a pentacam image of both eyes (only post op). they look better than the orbscan images.

kind regards

orbscan images: http://www.directupload.net/fi...900/gjmtsql6_pdf.htm
pentacam images: http://www.directupload.net/fi...900/nbtfdx4g_pdf.htm
Original Post
Hello freelancer,

Your first Orbscans are dated 10/6/03. I take it these were done BEFORE your procedure. Based on those scans there is the impression of forme fruste keratonconus in both eyes.

Did you wear hard (rigid) contact lenses BEFORE you had LASIK? Could you see clearly with eyeglasses BEFORE you had LASIK?

These things are necessary to know because they have direct bearing on the stability of your corneas over time. At first glance, it is easy to see the posterior float is abnormal, even before LASIK. And you had corneal surface irregularities BEFORE the procedure that was either (1) forme fruste keratonconus, (2) the result of hard contact lens wear or, (3) both combined.

The Orbscans, over time, do not show much progression, which is a good thing. The amount of corneal curvature change is consistent with the amount of your pre-LASIK myopia. We think of ectasia as progressive and certainly as something identifiable on the front surface of your eye causing marked distortion. If your condition has been relatively stable over time - that is - if your central corneal curvature has not changed appreciably, then I would say this is forme frusta keratoconus and not really ectasia. If ectasia was developing then the more recent curvature findings would be STEEPER (more sharply curved). Indeed, your findings appear stable.

With your pre-LASIK posterior float findings and surface irregularity, I am surprised the surgeon did LASIK.
Hello Dr. Hartzok,

thank you very much for your response!

Yes, the first Orbscans dated 10/06/2003 and were before the surgery.
Before LASIK I wear soft lenses and eyeglasses. I could see with eyeglasses very good and clearly. Also after LASIK I could see for about 4 years very good. But after that time I reached a point my vision got worse and worse over the years.

What do you think of the Pentacam images? Show they also forme fruste keratonconus or other irregularities? I heard Orbscan is not so exact like Pentacam to identifiy keratonconus or ectasia and they can indicate false positive results? is that right?

I can also not understand my surgeon did LASIK with this findings. As my vision got the first time bad i went regularly to my surgeon. He said everything is fine. It would have psychological causes...

What should i do know in my situation? Should i do a crosslinking (possibly combined with a PRK) to prevent further progression? I'm a little desperate and have fear that my situation will worsen.

Kind regards
The Pentacam imaging is becoming the standard but what you have with the Orbscans is a history of images over ten years and that is essential to look for stability.

Cross-linking would be indicated if progression was clearly the case. Corneas weakened by forme fruste keratoconus can be strengthened by cross-linking. However, strengthening the cornea does not necessarily correct the irregular astigmatism already present. You would probably still need to use rigid contact lenses for visual clarity.

The fact that you saw well for four years AFTER your procedure suggests that the cornea was weakened slightly by LASIK. But again, the Orbscans from 2004 do not look that much different than the ones from 2014. However, the rigid contact lenses might be molding the cornea and maintaining that consistent shape. If you discontinued wearing the hard lenses and the corneas steepened, then perhaps a case could be made for mild ectasia.

Has cross-linking been recommended to you by your doctor?
Hello Dr. Hartzok,

again, thanks for your response and help!

No, my doctor did not recommend cross-linking. But what could be worse my situation if a cross-linking would be made to prevent renewed progression? My concern are that the current stability won't last. Do progression come back once it reached stability?

If I wear rigid contact lenses could that cause a renewed progression?

Kind regards
In cases of keratoconus, often the diagnosis is only made when eyeglasses fail to correct the patient's vision to 20/20 and the examiner looks more closely at the corneal optics. When glasses fail to correct the vision, hard (rigid) lenses are prescribed. Many of my patients have shown no progression for decades, leaving me to wonder if the contact lens halted the progression or whether the condition might has been self-limiting to a degree. So it is with LASIK-induced ectasia. While there is a natural tensile strength to the cornea that is compromised in keratoconus, thinning of the cornea by ablation also compromises that tensile strength. The two processes are obviously different but, in either case, what is the critical minimum amount of corneal thickness (LASIK) or compromised corneal structure (keratoconus) before distension occurs and progression manifests?

We know that your cornea exhibited forme fruste (early signs) of keratoconus prior to LASIK. But how many people exist who might show early, minimal signs that go unnoticed? We don't know because we don't run Orbscans or Pentacams as a routine procedure. If we could identify them and follow them, then we would have a better handle on the odds of progression. Even then... how long would we follow them before prescribing hard contact lenses or doing cross-linking, at which time we have intervened and ended the study?

There is a push coming to have young children screened for keratoconus (Orbscans, Pentacams) and, upon findings of early changes, perform cross-linking. It sounds great. Why not prevent the distortion before it progresses to a level that requires rigid contact lenses? But, what we don't know, is where to draw the line on the DEGREE of measurability that signals the need for treatment. Industry would advocate for everybody to be treated. A conservative approach would be to wait until the patient begins to lose 20/20 acuity with eyeglasses.

So, in your case, is the contact lens holding things in check OR is your keratoconus / ectasia condition stable without the contact lenses? Patients who develop signs of post-LASIK ectasia do not automatically progress to perforation and, therefore, would be self-limiting. But the fact is this: Cross-linking is a simple and apparently safe procedure; it is hard to argue AGAINST cross-linking. If there is no progression, then the cross-linking gets the credit. If there would have been no progression without cross-linking, then that's fine also since there is no apparent downside.

To my knowledge, wearing hard contact lenses is not a risk for progression. (Inferences are occasionally made against contact lenses in an effort to support surgical care. If there are serious studies in support of those arguments, I would like to review them.) Chances are that you will still need hard contact lenses even after cross-linking because some degree of optical irregularity will persist on the corneal surface.
freelancer,

I'm sorry. I presumed you wore rigid (hard) contact lenses because in your first post you stated that only hard contact lenses give your good vision. Did you try to wear rigid lenses and have a problem wearing them?

A second important consideration in wearing rigid lenses is to monitor your vision for change elsewhere in the visual system; elsewhere meaning other than the cornea. If rigid lenses would fail to correct your vision, then it is important to determine the reason for the change.
Dry eyes can be a symptom of a less than optimal fit. The vast majority of contact lens fitters are not adept at fitting rigid lenses on post-LASIK eyes. In the U.S., optometrists even struggle to fit non-ablated eyes; fitting patients who have had LASIK and PRK is an entirely different paradigm. In other words, we struggle to find doctors with the necessary insight to properly prescribe lenses. Of course, finding knowledgeable fitters for patients who are struggling to see clearly following refractive surgery is what VSRN's network is all about. I will have Barbara Berney here at VSRN look for someone we can recommend.
I had refractive surgery in Mar16. Based on recommendation from surgeon , I end up 2 diff type of treatment for both of my eyes. vision for left acceptable but right(relex smile) poor vision , bleeding(eye white area)n cornea swollen right after surgery. Now the doctor couldn't tell what caused this blur vision.
Just found out, my stromal cornea tissue is <250micron. Am I on the high risk of getting this "Ectasia" ?

thank you for your advice.
Vivien, I had LASIK in 2001. I have less than 200 microns of stromal tissue left, and I do not have ectasia. Not everyone with thinner corneas gets ectasia, and a lot depends on how much cornea was ablated, the actual ablation zone, etc.

The number of patients who develop ectasia is actually small. Unfortunately, there is no good way to determine whether you will or will not, but the odds are in your favor that you will not.
Hi ,artistwoman

thanks for your reply.

based on calculation b4 treatment , i suppose to have
Left - 331 micron stromal bed , right - 293micron.

But after treatment end up with left-231 , right-244. something that cant understand.

based on attachement is the calculatin is appropriate?

seek for help

thanks
quote:
Originally posted by Vivien:
Hi ,artistwoman

thanks for your reply.

after so many years u have not encounter any symptom or problem? how do u take care of your eyes?

based on calculation b4 treatment , i suppose to have
Left - 331 micron stromal bed , right - 293micron.

But after treatment end up with left-231 , right-244. something that cant understand.

based on attachement is the calculatin is appropriate?

seek for help

thanks
The calculations appear to be appropriate. Not everyone with thinner corneas will get ectasia. I have had no symptoms, and the only care for my eyes is for dry eyes, with lid hygiene and hot compresses, dousing my eyes with unpreserved saline and using it to keep them hydrated throughout the day and night. I wear glasses for near, computer and distance and until I had a change in my prescription in the spring, I was wearing scleral lenses that cleaned up a lot of the aberrations in my daytime vision and gave me great acuity.
Hi artistwoman

Thank you for your reply again.

noted that femto lasik is a precision surgery.
based on my corneal thickness and pre op prescription , will you able to let me know what will the be calculation?

I would like to know am a suitable candidate for this customized femto lasik(left) and relex smile(right).

pre op data
Left Right
manifest refraction: SPH-8.25 SPH-7.25
CYL-2.25 CYL-2.25
Corneal thickness 568 569


SHP -100 = removed 12 microns?
CYL -2.25= how many micron to remove?
flap for femto = 100micron
Cap for relex = 120micron

Thank you artistwoman.
I am not a surgeon, so I cannot tell you what the calculations are, but based on the information you provided earlier, the numbers do add up. They are not perfect, because NOTHING is perfect. And regardless of how "precision" femto LASIK is supposed to be, it is not perfect. There is no such thing.

As for your candidacy, you were near the top of the range, but still considered a candidate. Do you have the data for your post-op numbers from a scan, or are the numbers provided what they estimated you would have? Do you know for a fact that your flap was actually 100 microns, and that the Relex cap was actually 120 microns, or is that what it was supposed to be?

My corneas were only 544 microns, my flap turned out to be 220 microns, and my pre-op prescription was -10.5 with 2 cylinders of astigmatism. I was NOT a good candidate.

However, I would not say anyone is a good candidate for refractive surgery, as I've seen too many people with complications, even those considered to be excellent candidates.
I had a scan done in 2004 that measured within one micron accuracy the thickness of the flap and the stromal bed. According to my surgical report, it was supposed to have been no more than 160 microns. That scanner is no longer in use, but there may be others that can measure now.

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