Aim.To compare the degree of posterior capsule opacification (PCO) after AquaLase and NeoSoniX phacoemulsification methods during an 8-year follow-up period using two types of software. Design. Prospective, randomized clinical trial. Methods. AquaLase was used in the right eye and NeoSoniX in the left eye of each patient with bilateral cataract. Results. Fifty patients were analyzed 1 year, 46 patients 3 years, and 37 patients 8 years after cataract surgery. Mean EPCO 2000 values were for the AquaLase group 0.324 ± 0.305 and for the NeoSoniX group 0.298 ± 0.341 (P = 0.53) 1 year after surgery, for the AquaLase group 0.582 ± 0.506 and for the NeoSoniX group 0.594 ± 0.515 (P = 0.87) 3 years after surgery, and for the AquaLase group 0.648 ± 0.567 and for the NeoSoniX group 0.673 ± 0.542 (P = 0.30) 8 years after surgery. The OSCA results were for the AquaLase group 0.7097 ± 0.3778 and for the NeoSoniX group 0.8584 ± 0.4323 (P = 0.046) 1 year after surgery, for the AquaLase group 0.9667 ± 0.736 and for the NeoSoniX group 0.9540 ± 0.5250 (P = 0.91) 3 years after surgery, and for the AquaLase group 1,035 ± 0,952 and for the NeoSoniX group 1,103 ± 0,741 (P = 0.44) 8 years after surgery. Conclusion. There was minimal PCO difference between these 2 approaches, AquaLase and NeoSoniX. Neither AquaLase nor NeoSoniX technique was able to prevent a natural progression of PCO.