Automated Lamellar Keratoplasty (ALK)

Automated lamellar keratoplasty (ALK) was done on high myopes prior to the invention of the excimer laser. ALK is not performed today. LASIK has essentially replaced ALK because of the increased accuracy and safety afforded by the excimer laser in making the second “cut.” ALK is similar to LASIK in that it uses a microkeratome to separate the surface layer of the cornea. This flap is temporarily folded back (similar to the first part of the LASIK procedure), and a thin disc of corneal tissue is removed with a second pass of the microkeratome. ALK, much less precise than LASIK, was associated with a much higher complication rate. It was primarily used to correct large amounts of myopia.

Satisfactory results are not always obtained the first time, and a high percentage of people needed additional procedures to achieve the desired result. Sometimes an irregular corneal surface results from the procedure, causing some distortion of vision (astigmatism).