The Laser evaporates the corneal tissue and in this way alters the curvature of the eye. The laser can be applied to either the surface of the eye (PRK/LASEK/ASA) or deeper in the cornea under a superficial flap (LASIK and INTRALASIK). Having prepared the eye, the laser beam is then applied. The laser can be either of a standard type or of a more advanced WAVEFRONT type.
Will it be painful?
No, the procedure lasts 1-2 minutes and is entirely painless.
How long is the recovery?
The recovery time is usually within the hour. You will notice that your vision becomes sharper. The scar tissue usually does not return. Dr. Chu will need to see you for a follow up appointment.
LASIK
LASIK involves the creation of a superficial partial thickness corneal flap (see figure). The flap is created with a "microkeratome", a specilaised highly refined instrument which uses an oscillating blade.
Laser is performed underneath the flap, and then the flap is replaced.
The main advantage of Lasik is very rapid healing, and most people see well enough to function normally the next day. The disadvantage compared to PRK is that it is a slightly more complicated and invasive procedure.
A thick and very regular cornea is required for this technique.
Lasik is the preferred technique for far-sighted (hyperopic) candidates as results tend to be better with this technique.
PRK/LASEK/ASA
PRK/Lasek/ASA is performed directly on the corneal surface, after gently removing the surface "skin" layer called the epithelium.
The advantage of this technique is that it is a simple one stage procedure (see figure), and minimally invasive. In LASEK, which Dr Fink performs, the epithelium is slid back in to place after the laser treatment, which makes the eye more comfortable.This is not crucial as a fresh layer of epithelium grows in during the first few days. In PRK the old epithelium is simply removed and not replaced. With ASA, the epithelium is removed with laser with any remants wiped off.
A contact lens is placed on the eye for comfort and to aid healing. This is generally removed after about 4-5 days.
The disadvantage is the slightly slower healing. Your eyes may be sensitive and vision may be blurry on average for the first 3-5 days as the new healthy epithelium grows in. This is a small price to pay for the years of great vision to follow and a very safe form of laser treatment.
PRK is the original form of laser vision correction with more than 15 years experience. Longterm results show excellent stability and patient satisfaction.
It is now practised in a more advanced fashion, including newer techniques for removing the epithelium, superior laser performance, and techniques for improving healing and better post-operative management.
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