方法：将年龄相关性白内障患者149例149眼随机分为预劈核组(A组)77眼和非预劈核组(B组)72眼。分别使用撕囊镊预劈核和非预劈核技术进行白内障超声乳化术，记录术中超声能量、平均超声乳化时间、术中并发症、术后1d，1wk裸眼视力和术后1、3d，1wk角膜水肿等情况并进行比较。

结果：将两组中同级核硬度的亚组进行比较，A组的平均超声乳化时间低于B组，差异有统计学意义(P<0.05)； 且前者术后第1、3d角膜水肿轻于后者，差异有统计学意义(P<0.05)，术后1d裸眼视力A组优于B组，差异有统计学意义(P<0.05)，术后1wk两组裸眼视力无统计学差异(P>0.05)。术中出现晶状体后囊膜破裂A组2眼(2.6%)，B组有3眼(4.2%)，两组比较，差异无统计学意义(χ²=0.28，P>0.05)。

结论：与非预劈核相比，撕囊镊预劈核操作更简便，术中超声时间更短，角膜水肿程度更轻，术后早期裸眼视力更好。

METHODS: Totally 149 cases of age-related cataract were randomly divided into using pre-chop(Group A)and non-pre-chop(Group B)techniques groups, for Group A patients received phacoemulsification after pre-chop by using capsulorhexis forceps. The ultrasonic energy, average phacoemulsification time, intraoperative complications, 1d, 1wk uncorrected visual acuity(UCVA)and 1d, 3d,1wk postoperative corneal edema were recorded and compared.

RESULTS: The subgroups of the same group of nuclei were compared in the two groups. The ultrasonic time in Group A was lower than that of Group B, and the difference was significant(P<0.01). Also the corneal edema in the former was lighter than that of the latter(P<0.05). There was difference in uncorrected visual acuity(UCVA)between groups(P<0.05).

CONCLUSION: Compared with non-pre-chop, the time of ultrasound in pre-chop group was shorter, the degree of corneal edema was lighter and early postoperative UCVA was better.