Step One: The Laser Flap

Every Cornea is Different

Every corneal flap is different, too. But there are certain characteristics that every flap must have, including precise diameter, centration and thickness, thereby setting the stage for your doctor to perform an excellent Step Two. 

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.

Creating the Laser Flap

The INTRALASE^® laser actually represents a breakthrough in the field of ultrafast laser science. Generating light pulses as short as one-quadrillionth of a second, femtosecond laser technology has opened new fields of scientific study and provided the basis of femtochemistry research that won the 1999 Nobel Prize in Chemistry.

The use of the femtosecond laser in the field of ophthalmology was developed by a team of physicists, biomedical engineers and ophthalmologists at the Center for Ultrafast Optical Sciences and the Kellogg Eye Center of the University of Michigan.

The IntraLase ultrafast femtosecond laser is the first bladeless laser technology for performing Step One of LASIK and the most accurate technology for corneal flap creation available today. The laser uses an infrared beam of light to precisely separate tissue through a process called photodisruption. In this process, the focused laser pulses divide material at the molecular level without the transfer of heat or impact to the surrounding tissue.

• IntraLase creates the flap using an "inside-out" process.
• The silent beam of laser light is focused to a precise point within the stroma (central layer of the cornea) where each pulse of the laser creates a tiny 2- to 3-micron bubble of carbon dioxide and water vapor.
• Thousands of these microscopic bubbles are precisely positioned to define the flap's dimensions, as well as the location of the hinge.
• Bubbles are then stacked along the edge of the flap up to the corneal surface to complete the flap.
• The process from start to finish takes approximately 45 seconds.
• The surgeon then lifts the flap to allow for treatment by the excimer laser.  When treatment is complete, the flap is repositioned.

With IntraLase, your doctor can create a corneal flap of exact diameter, depth, hinge location, centration, and overall architecture. Such accuracy and precision are nearly impossible in a hand-held blade.