Wavefront Guided Lasik (Customized Lasik or C-Lasik) is a fast emerging as well as a better tool to restore the quality of vision. The surgical procedure remains the same. Customized Lasik can be better known as ‘Eagle’s Eye Vision’. It is the next generation of Excimer laser and creates a customized “perfect shape” to the surface of the eye to allow an “ideal focus”.
There are several machines available in the market to measure the spherical and cylindrical aberrations of the eye. e.g. Zyoptics (Bausch & Lomb) & OPD Scan (Nidek). Out of the machines available OPD Scan from Nidek appears to be the best machine till date. At our center this is the machine that is being used.
Sophisticated software then converts the map into the Clinical Ablation Profile prescription. The prescription is transferred electronically to the computer controlling the laser. The computer calculates the shot pattern (i.e., where and how the laser will operate on the cornea) required for the correction of both the patient’s lower and higher order aberrations. These laser machines are the latest generation machines with special laser delivery systems capable of handling such corrections.
Data map of optical imperfection in a human eye which is accessed by Wavefront Technology is then corrected by the laser.
Prerequisites of Laser Surgery
Like any laser surgical procedure, the go-ahead for Lasik surgery is not given to every spectacle user. Some of the prerequisites of laser surgery are:
- The candidate should be at least 18 years old.
- The candidate should not be suffering from any eye disease/infection.
- The candidate should not be pregnant, nursing or planning to conceive.
- The eye prescription should be stable for about a year and the refractive error should fall within the permitted range for Lasik.
- Anybody who wishes to consider Lasik eye surgery must be willing to understand its potential risks, complications and side effects which are duly explained by the surgeon.
The surgeon uses a microkeratome to create the flap. The flap is then positioned to one side of the corneal “bed” as the Excimer laser beam (left) is applied. The laser ablation is completed and the flap is replaced. Once the flap is returned to preoperative position, the surgeon carefully checks and rechecks the flap to be certain it is secure and well-positioned.
Lasik involves extensive computer analysis of the eye. Patient is then asked to come on the scheduled day for the laser treatment. Local anesthetic eye drops are instilled in the eye to achieve a pain free procedure. The patient is now made to lie under the laser machine and asked to fix his gaze at a red light. The data of the patient is fed into the computer memory of the laser. A special machine called the microkeratome is used to pick up a thin corneal flap of 160 microns. Laser is delivered to the cornea under this flap to correct the spectacle number. It takes 20 to 60 seconds to complete the laser delivery to one eye. The corneal flap is placed back in position where it holds strongly within two minutes due to its natural bonding properties. The entire procedure takes about 10 minutes.
Benefits of C-Lasik Surgery
The potential benefits of Customized LASIK are as follows:
- Greater chance of achieving 6/6 vision.
- Greater chance of achieving better than 6/6 vision.
- Reduced chance of losing best corrected vision.
- Reduced chance of losing visual quality or contrast sensitivity.
- Reduced chance of night vision disturbances and glare.