Experimental femtosecond laser lens surgery

Abstract

AbstractPurpose To review the current developments and new experimental applications of femtosecond lasers (FsL) in lens surgery, including cataract and the treatment of presbyopia. FsL lentotomy has been shown effective to soften the lens matter easing cataract extraction. Because the main cause for presbyopia is the stiffening of the lens nucleus with age, FsL lentotomy could be applied to treat it, provided the cuts inside the lens do not induce a significant opacity.Methods Commercial FsL lasers systems for cataract surgery are already available, using repetition rates of 100 kHz at 1041 nm, similar to those of corneal FsL. We have developed a custom build multimodal non‐linear microscopy platform modified to work as a nano‐surgery scalpel using a FsL with a repetition rate of 80 MHz at 860 nm. This allows cutting inside the lens matter at a much smaller scale than the current lens surgical FsL systems.Results Using a single FsL system, we imprinted complex patterns in 2D and 3D configurations inside human donor lenses. These results were analyzed through transmitted infrared light and Two‐Photon Excitation Fluorescence (TPEF) microscopy. We observed an increase of the TPEF signal on the targeted regions. In addition, we found that the caused damage is highly confined without any apparent effect on the surrounding tissue.Conclusion While current FsL lentotomy systems can soften the lens nucleus to ease cataract extraction, optical quality at the optical axis is compromised. Experimental FsL with modified parameters is able to further confine the damage in order to preserve the lens clarity, a requirement for FsL lens presbyopia surgery.