The goal is to develop a combined technique for preliminary YAG laser fragmentation and Femto laser exposure on a CATALYS device and to evaluate its role in reducing the time and energy parameters of a surgery of high-density cataract.
 Material and methods. The study included 118 patients (118 eyes) with age-related cataracts of the 3rd and 4th degrees of lens nucleus density. In the main group, before phacoemulsification (PE) with a Femto laser support and IOL implantation, preliminary YAG laser phacofragmentation of the lens nucleus was performed. In the first control group, PE was performed with Femto laser support and IOL implantation. In the second control group PE with IOL implantation.
 Results. A 35% decrease in the energy of the Femto laser action at a 3rd degree of lens nucleus density was achieved, and 40% at the 4th degree, in comparison with the PE with the Femto laser support without preliminary YAG laser phacofragmentation, a 38% decrease in the cumulative ultrasound energy at 3rd degree of the lens nucleus density, and 42% at 4th degree compared with isolated ultrasonic cataract phacoemulsification.
 Conclusion. The proposed modification of the technique of combined YAG laser and Femto laser exposure allows achieving during cataract surgery a complete fragmentation of the lens nucleus of a high degree of density, helps minimizing the risk of complications and reaching quick postoperative rehabilitation of patients.