Abstract:  Objective To analyze the effect of a new phacoemulsification technique in the treatment of hard nuclear cataract. Design Retrospective case series. Participants One hundred ninety eight patients with hard nuclear cataract were enrolled in this study. Methods Phacoemulsification and intraocular lens implantation were performed. Patients were divided into two groups: A, burst mode using a crushing and chopping technique, and B, a continue mode with a divide and conquer technique. Main Outcome Measure Phaco power, phaco time, visual acuity, corneal edema and corneal endothelial cell loss were evaluated at day 1, and 1 week and 1 month postoperatively. Results Average phacoemulsification power in group A and group B were 8.1%±1.3% and 27.0%±3.4%, respectively. Average phaco time was 59.2±5.8 seconds and 256.1±14.5 seconds in group A and B, respectively. The differences were statistically significant (all P<0.001). Endothelial cells loss was 4.5±2.4% and 9.5±5.4% in group A and B, respectively. One day after surgery, 70 cases (68.0%) in group A and 12 cases (12.6%) in group B achieved corrected visual acuity of 0.5 or better. The difference was statistically significant (P<0.001). One day after surgery, 72(69.9%) and 13(13.6%) patients were found to have grade I corneal edema, and 6(5.8%) and 35(36.8%) cases had grade IV corneal edema, in group A and B respectively. Posterior capsular rupture only occurred in one case in group B. Conclusion Compared with the continue mode, phacoemulsification with the burst mode and an effective chop technique may reduce phaco power and time for the treatment of patients with hard nucleus. Burst mode seemed to be more effective with less complications. (Ophthalmol CHN, 2013, 22: 94-97)

Key words: cataract/surgery; , phacoemulsification