To create a hinged ‘flap’, the microkeratome is used like a carpenter’s plane to shave a thin layer of the cornea. Play procedure animation

Results using the microkeratome have always been considered good, but that was before IntraLase.

Traditionally, doctors have used a noisy mechanical procedure to create the flap. In this method, the doctor cuts across the cornea using a hand-held microkeratome with an oscillating blade. Achieving accurate depth, flap thickness, and centration on a curved cornea of varying dimension can be difficult with a microkeratome. The precision of this step is highly dependent upon the performance of the microkeratome device, which may be unpredictable despite a high degree of surgeon skill.

While LASIK complications are rare, all surgery carries some degree of risk. It is for this reason that the advanced IntraLase laser was developed - to significantly reduce the majority of LASIK complications that typically occur when using the traditional mechanical microkeratome (or ‘blade’) to manually cut the corneal flap.

How The Microkeratome Works

To create a hinged ‘flap’, the microkeratome is used like a carpenter’s plane to shave a thin layer of the cornea.

[show video of procedure]

First, a vacuum ring is placed over the eye to hold it in place. This vacuum produces a minor stretching force on the cornea. During this process, vision will dim or even darken completely.

Then, like a carpenter's plane, the oscillating blade of the microkeratome cuts a corneal flap varying from 100 microns to 200 microns in thickness, leaving a small section of attached tissue to act as a hinge.

The flap is then gently lifted back like the page of a book to expose the underlying stroma. The excimer laser is then used to ablate a measured amount of corneal tissue, in order to effectively correct the patient’s visual defects. The surface of the stroma and flap are then irrigated, after which the flap folded back to its original position to allow the eye to heal. Due to the self-sealing nature of the flap, no sutures are needed. Following surgery, the doctor checks the stability and adherence of the corneal flap to make sure it has not lifted or become dislocated.

One chance to get it right

A failed microkeratome procedure (or partially cut flap) cannot be re-attempted until the flap has completely healed. Subsequently, the LASIK procedure is cancelled and the patient is sent home for approximately 3 months (or more) before the surgeon can re-attempt a LASIK procedure. During that time, the partially cut flap may be susceptible to dislocation, ingrowth and other various complications.

Unlike the microkeratome, the IntraLase laser can be stopped and started, at will, during the same procedure, with no detrimental impact on the corneal flap or visual result. The computer-controlled laser knows precisely where to continue the cut, allowing the surgeon to continue the procedure where he/she left off.