Femtosecond Laser Arcuate Keratotomy is a treatment performed to reduce astigmatism. This is achieved using the LenSx femtosecond laser to precisely create curved incisions in the periphery of the cornea. FLAK can be performed in combination with refractive lens exchange or laser-assisted cataract surgery or as an isolated procedure. It can be used to address higher levels of astigmatism that can follow corneal transplantation surgery. The FLAK procedure is painless and rapid – the procedure is usually completed within minutes with the laser operating only a few seconds.