One of the supposed risks and complications of getting Laser-Assisted in Situ Keratomileusis (LASIK) surgery is corneal thinning called post LASIK ectasia. Along with this condition comes a steady deterioration in the patient’s vision.
The condition may happen anytime from as soon as a week after the surgery, up to as long as several years after the said procedure. To manage post LASIK ectasia, a corneal transplant procedure is required in severe cases. With the increasing popularity of LASIK surgeries, there has been a heightened concern about this condition.
But is it really ectasia?
Daniel S. Durrie, M.D., a clinical professor of ophthalmology at the University of Kansas in the United States, has taken a close look at the matter.
Crunching the Numbers
Based on the figures Dr. Durrie compiled from LASIK surgeons who have done more than ten thousand of the said procedure in the past ten years indicate that the number of post LASIK ectasia cases that they have had is usually less than 1 out of every 2,000 cases. Curiously, that is also the same incidence rate for the number of keratoconus cases in a given population.
Add to that the fact that around 90% of those with post LASIK ectasia cases also exhibited signs of genetic keratoconus. Dr. Durrie also put the number of those with post LASIK ectasia without possessing genetic keratoconus at around 1 to 2% of the total cases. And even that small number showed, upon a review of their eye topographies before the operation, an abnormality that makes them suspicious of keratoconus.
While Dr. Durrie acknowledged that the LASIK surgery may indeed aggravate the genetic keratoconus of a patient, this procedure does not seem to create the new disease of ectasia.
History Repeating Itself
This situation of mistaking keratoconus with ectasia can be compared to the mistaken notion in the late 90s when everyone thought that LASIK surgery could lead to a long term problem with dry eye syndrome. After further studies however, it was concluded that while the procedure could indeed cause a temporary decline in tear flow and corneal sensation as a result of LASIK cutting across the nerves of the cornea, normalcy returns about a year after the surgery. Preexisting conditions of dry eye syndrome, as well as blepharitis, could also be aggravated by LASIK surgery. This worsened the matter and strengthened the initial belief that the procedure was causing dry eyes.
The Thin Fact
Dr. Durrie also made a very significant observation. LASIK surgery thins the cornea in the center. If this is indeed the problem, then it follows that the bulge should also come out of the thinnest part of the cornea, namely its center.
It does not add up, however, because the cornea does not bulge there. Instead of the center, the bulge appears in a temporally inferior location. This location is exactly where a keratoconus makes an appearance.
How Should it be Managed?
Post LASIK Ectasia should be managed in the same way as Keratoconus:
It should be monitored for progression. Any signs of progression are probably best treated with Collagen Crosslinking.
A while back we discussed a procedure called KeraFlex, which as yet (surprisingly) has not been introduce to Australia yet.
If vision is slightly affected often just glasses will correct any annoying blur.
Soft contact lenses
Customised rigid gas permeable contact lenses
Synergeyes Hybrid contact lenses
Intacs / Kera Rings
And finally if all other options have been exhausted we would consider a corneal transplant.
One of the main reasons that a patient decides to go ahead with LASIK is to be independent of all optical aids. Unfortunately in the context of Post LASIK Ectasia optical aids whether it be glasses or contact lenses are inevitable.
At The Eye Practice, Dr Jim Kokkinakis has probably seen the most cases of Post LASIK Ectasia in the country from a spectacle or contact lens perspective. This is because being recognised by his peers as an expert contact lens fitter that has spent over 6 years working as a part time consultant in the largest laser eye surgery centre in the country, he has had many referral for this very frustrating condition.
If you have had laser eye surgery and now notice that your vision is not as good as it used to be, before considering any enhancement procedure it would be better to be assessed by Dr Kokkinakis to get to the bottom of the vision deterioration.
Make an appointment by either CLICKING HERE or call Jim Kokkinakis on (02) 9290 1899.