Principles of Refractive Index Shaping of IOLs with Femtosecond Laser

The use of a femtosecond laser to alter the hydrophilicity of targeted areas allows one to build a refractive index shaping lens within an existing IOL. This video focuses on the chemical changes and the lens creation within the targeted area leading to IOL power change and the differences between the laser system used in this application and systems used in cataract surgery. Power and modulation transfer function (MTF; Lambda-X PMTF) of commercially available single-piece acrylic lenses were measured before and after laser adjustment. Treatments demonstrated included spherical, toric, and spherocylindrical changes, as well as induced multifocality and canceled multifocality. Lenses were also analyzed under laser-induced fluorescence microscopy.