Purpose. To evaluate a laser energy safety level by comparison of corneal endothelium cells response after various methods using energy of ultrasound and laser phacofragmentation.Material and methods. Ultrasound phacoemulsification (Millennium) was performed in 3 right cadaver human eyes (males, 68-72 years) 6 hrs post mortem. Laser phacofragmentation was performed in 3 left eyes of the same individuals using the Russian device “Rakot” (Nd:YAG 1.44μm). Electron transmission microscopy (ETM) of pigment epithelium in macular area of retina was carried out.Results. Electron microscopy of corneal endothelium monolayer after laser phacofragmentation found NO significant abnormalities. After ultrasound phacoemulsification we detected areas with defects in endothelium monolayer sized 3-7 cells with round shape and smoothened cushion –like edges incorporating endothelial cells fragments with mostly cell nuclei parts. Posterior surface of the descemet’s membrane was a bottom of the existing hollow defects.Conclusions. Compared to ultrasound energy the laser energy in phacofragmentation inflicts NO adverse effects on highly sensitive corneal endothelium
