Namaste,Lasik for someone with very bad vision
is fraught with danger.
The Munnerlyn Formula
determined that a minimum
of 12 microns of corneal
tissue must be removed to effect a 1.00 diopter
change of refractive error
. If a wavefront-guided ablation
is used, this can go up to 18 microns per diopter.
You use the term iLasik
, which is the marketing term used by a laser manufacturer to indicate Bladeless Lasik
. This is regular Lasik
with a femtosecond laser
created flap. This type of Lasik flap can be created about 110 microns thick.
Let's do the math. In the worst eye the spherical equivalent
is 11.00D/SE diopters. The amount of tissue to be removed is 132-198 microns. We will assume that the flap will be 110 microns. The corneal thickness is 510. Subtracting the amount of tissue to be removed and the depth at which it will be removed from you corneal thickness allows for 202-268 microns of untouched cornea. Many studies have shown that if at least 250 microns of cornea remain untouched, a healthy cornea will remain stable. You may think that you might be able to have iLasik if you do not use wavefront, but we are not finished.
It is common for a large change in refractive error to regress
. It would be reasonable to expect about 2.00 diopters of regression for an 11.00D/SE correction. This means you would need enhancement surgery
to resolve the 2.00 diopters of regression, which means an extra 24-36 microns of tissue removal. Now your untouched cornea would be 166-244 microns.
Although studies are less conclusive, it appears that the cornea will not remain stable if more than half its thickness is removed. iLasik would affect more than half your corneal thickness.
Your cornea after iLasik would be too thin and too compromised to remain stable. You would likely suffer from corneal ectasia
and would require a full corneal transplant. iLasik would not be safe for you.
The alternative laser vision correction technique would be PRK
and it does not require the Lasik flap. This would eliminate the need to disrupt 110 microns of cornea for the flap, but even without the Lasik flap you would have only 276-354 microns of untouched cornea. This is so marginal as to be unsafe. Furthermore, PRK would be more likely to cause corneal hazing
. There are workarounds for the haze concern, but you are at risk of your corneas changing from clear to white.
Another issue is the resulting curvature of the cornea. After removing 11.00D/SE your corneas would be very flat. This is likely to cause severe halos
around light sources at night. You would probably not be able to drive at night.
Before any elective eye surgery you shoulde have an evaluation of your retina
by a qualified specialist. High myopia places a lot of stress on the retina and can lead to retinal detachment
Corneal vision correction surgery is too risky for you. You way want to consider Phakic Intraocular Lenses (P-IOL)
or Refractive Lens Exchange (RLE)