About LASIK

Why LASIK is called "flap and zap"

If you are having LASIK, please read the other pages in this section carefully. The following are results graphs for my last few months results. Most are taken at 3 months post op.

 

Running Audit of my results (using the Wavelight Eye-Q 400 Hz laser - March 2013 )

(results are the same for LASIK and LASEK)



Picture 1: Accuracy Levels: The middle line is spot on and the dotted lines are +/- 1 Dioptre. As you can see, this is a very accurate and safe laser, Both LASIK and LASEK results are in the myopia charts. 

Picture 2: Another Accuracy Graph: Driving standard is about -0.75 Dioptres. A patient who gets even one eye within half a Dioptre is usually very pleased. 

Picture 3: Astigmatism Results: There is usually a bit more scatter with astigmatism as there is an axis that varies as well as the size.

Picture 4: Safety for treating myopia (short sight): "No harm" is no loss of Best Corrected Spectacle Visual Acuity (BCSVA). One line loss is usually not noted by the patient line loss as a measure of safety. The chart plots how many lines gained or lost on the standard Snellen vision chart. Most stay the same. Of those who gain sharpness of vision, a lot do so because of magnification effects; glasses make the object size smaller, whereas contact lenses and Lasik do not.

The FDA counts the loss of 2 lines of vision as a complication. One line loss or gain can vary depending on the room the test is done in, the tiredness of the patient etc.


Picture 5: Defocus Equivalent: A technical graph of accuracy made by the numerical addition of the sphere and half the cylinder without taking into account the sign. ( +1 / -2 x 180 has a spherical equivalent of 0 but a defocus equivalent of 2). It is a truer measure of accuracy than the spherical equivalent used in other graphs. (sphere + half the cyl taking into account the sign).

Picture 6: Results for hyperopia (long sight): Wavelight Laser:

In hyperopia, the image size is bigger with glasses and smaller with contact lenses or Lasik/PRK. Hence there is a tendency, opposite to myopia, to lose sharpness of vision with contact lenses or Lasik because of the image size difference.

The average age of people presenting for hyperopic lasik is around 46y, whereas the average age for myopia is 33y. This is because the hyperopes can manage until middle age until their fails. There is nothing worse than a middle aged hyperope as they can see neither distance or near. Correspondingly, they are often amongst the happiest patients following refractive surgery.

I have also scanned in a recent article (April 2010) about this laser from an ophthalmic magazine called Ocular Surgery News.