Application of different mode in phacoemulsification of hard nucleus cataract

Objective To investigate the application of continuous,pulse and burst modes in phacoemulsification of hard nucleus cataract.Methods 212 eyes(185 patients)of hard nucleus cataract(LOCS Ⅱ criteria≥Ⅲ degree)were randomly divided into 3 groups(continuous group,pulse group and burst group).Various phaco modes were used The differences in amount of balanced salt solution use throughout phaco time,actual power(AP),the effect phaco time(EPT),and accumulated energy(AECP),endothefial cell loss and corneal incision burn were compared among the three groups.Results The amount of balanced salt solution use throughout phaco time of the burst group was far less in comparision to those of the other two groups.The difference was statistically significant (P＜0.05).There was no statistically significant difference in actual power between burst and pulse group(P＞0.05).The mean EPT and AECP of burst group were statistically lower than those of the pulse group(P＜0.05).AP,EPT and AECP of burst group were significantly much lower than those of the continuous group(P＜0.05).The mean density of endothelial cell of burst mode was much higher than those of continuous and pulse group 1 week after surgery and endothelial cell loss rate was significantly lower than those of the two other groups(P＜0.05).No serious corneal incision burn occurred in each of the three groups.Conclusion The use of burst mode in hard nucleus cataract reduces significantly the amount of balanced salt solution use throughout phaco time and the amount of accumulated energy,which causes diminished injury to surrounding ocular structures and improved surgical efficiency.Burst mode is advised for its efficiency in energy utilization in phacoemulsification. Key words: Phacoemulsification ;  Burst mode ;