PURPOSE: To investigate femtosecond laser-assisted nanosurgery of the posterior capsule in a prospective in vitro animal study. SETTING: Department of Ophthalmology and Eye Hospital, University of Saarland, Homburg, and Fraunhofer Institute for Biomedical Engineering, St. Ingbert, Germany. METHODS: The posterior capsules of 12 porcine eyes were irradiated with a nonamplified 90 MHz near-infrared 750 nm titanium:sapphire femtosecond laser. Intratissue and superficial laser cuts of laser-ablated (5 capsules) and control (1 capsule) specimens were examined by femtosecond multiphoton laser scanning microscopy (MLSM) and transmission electron microscopy (TEM). RESULTS: Laser exposure time and pulse power determined the width of the lesions, which ranged from 0.69 microm+/-0.19 (SD) to 2.81+/-0.5 microm. Both MLSM and TEM revealed minimal collateral alterations in the tissue surrounding the laser cuts. CONCLUSIONS: Nonamplified near-infrared femtosecond laser pulses at low pulse energies may be a promising strategy for precise lamellar noncontact nanosurgery of the posterior capsule, with minimal structural collateral damage to surrounding tissue. High-resolution MLSM offers 3-dimensional, noninvasive, nondestructive imaging at submicrometer resolution within seconds before and after ablation.
PURPOSE: To investigate femtosecond laser-assisted nanosurgery of the posterior capsule in a prospective in vitro animal study. SETTING: Department of Ophthalmology and Eye Hospital, University of Saarland, Homburg, and Fraunhofer Institute for Biomedical Engineering, St. Ingbert, Germany. METHODS: The posterior capsules of 12 porcine eyes were irradiated with a nonamplified 90 MHz near-infrared 750 nm titanium:sapphire femtosecond laser. Intratissue and superficial laser cuts of laser-ablated (5 capsules) and control (1 capsule) specimens were examined by femtosecond multiphoton laser scanning microscopy (MLSM) and transmission electron microscopy (TEM). RESULTS: Laser exposure time and pulse power determined the width of the lesions, which ranged from 0.69 microm+/-0.19 (SD) to 2.81+/-0.5 microm. Both MLSM and TEM revealed minimal collateral alterations in the tissue surrounding the laser cuts. CONCLUSIONS: Nonamplified near-infrared femtosecond laser pulses at low pulse energies may be a promising strategy for precise lamellar noncontact nanosurgery of the posterior capsule, with minimal structural collateral damage to surrounding tissue. High-resolution MLSM offers 3-dimensional, noninvasive, nondestructive imaging at submicrometer resolution within seconds before and after ablation.