METHODS: One hundred and twenty-six patients(158 eyes)of age-related cataracts with nucleus density at grade Ⅲ-Ⅳ were randomly divided into two groups. Group A was performed a manual prechop technique using a surgeon-bent cystotome after the capsulorhexis, while group B was performed traditional phaco-chop without prechop technique. The average power(AP), actual ultrasonic time(U/S time), accumulated energy complex parameter(AECP)of machine, average density of endothelial cells, endothelial cells loss, uncorrected visual acuity(UCVA), corneal edema and intraoperative complications were compared between groups.

RESULTS: The AP, U/S time and AECP of Group A were significantly lower than that of Group B(P<0.05). At postoperative day 1, the corneal edema of Group A was slighter than the control with significant difference(P<0.05), so was the UCVA. While there was no significant difference of UCVA between groups at postoperative 1wk. The average corneal endothelium density of Group B was significantly lower than that of Group A at postoperative 1wk, and the average cell loss was higher than that of Group A. Two eyes of group A had posterior capsular rupture compared to 4 eyes of Group B.

CONCLUSION: Compared with traditional phaco-chop, the cystotome-assisted prechop technique presents shorter intraoperative ultrasound time and lower energy, while contributes to less corneal endothelial cell loss and better early postoperative UCVA.