A microkeratome is a precision surgical instrument with an oscillating blade designed for creating the corneal flap in LASIK or ALK surgery.
The femtosecond laser emits ultrashort pulses that act as a blade to cut through the eye with precision and accuracy.
[7] He developed the microkeratome for his keratomileusis (surgical reshaping of the cornea) procedure to correct the refractive error in the eye, which has evolved into the LASIK surgery of the 21st century.
In 1958, Barraquer performed a lamellar resection in situ(corneal tissue replacement), where he used a prototype microkeratome that moved along a ring without a guide.
Barraquer's surgery required the creation of a free flap, which meant the cornea was completely cut through.
In 1991, Ioannis Pallikaris introduced the concept of a corneal hinge, which kept the cornea flap attached and helped with the healing process.
The motorized microkeratome contained a system of gears that ensured a constant blade velocity for a consistent flap thickness.
[12][14] Advanced Medical Optics created the amadeus microkeratome, which used a single-hand design that lowered the learning curve for new surgeons.
However, most surgeons and patients tend to prefer the bladeless femtosecond laser, due to its precision and safety.
Depending on the required flap diameter and the form of the cornea, different suction rings are employed.
The standard oscillation speed of the blade is 15,000 rpm with an engagement angle between 24° and 30° depending on the required flap thickness.
The suction ring comes in either disposable plastic or metal and applies pressure from about 60 to 160 mm Hg, to stabilize the eye for a clean cut.
The oscillating blade of the microkeratome then proceeds across the eye at a steady velocity, so that the thickness of the flap created is precise.
For a more precise flap thickness, the surgeon must pay attention to the blade's sharpness, protrusion, angle, oscillation speed, and velocity.
The microkeratome then reverses out of the cut, which allows the suction to be released from the eye to decrease the risk of epithelial defects.