方法：本研究为随机对照临床研究。随机选择209例209眼晶状体核硬度为4级(Emery分级标准)的年龄相关性白内障患者，并随机分为两组接受同轴微切口超声乳化手术。试验组(104眼)应用同轴微切口扭动模式超声乳化手术，对照组(105眼)应用同轴微切口常规模式超声乳化手术。记录术前最佳矫正视力(best-corrected visual acuity，BCVA)、眼内压(intraocular pressure，IOP)、中央前房深度(central anterior chamber depth，ACD)、角膜内皮细胞计数(endothelial cell count，ECC)； 术中累积消散能量(cumulative dissipated energy，CDE=有效超声时间×实际超声能量)及灌注液消耗量(esstimated fluied used，EFU)； 术后第1d； 1wk； 1mo的BCVA，IOP，ECC，ACD及手术并发症。

结果：两组白内障均为4级核，术眼生物学参数分析，BCVA值、IOP值、ACD值与ECC值试验组低于对照组，但差异无统计学意义(P>0.05)。术中CDE及EFU分析，试验组均低于对照组，差异有统计学意义(P<0.05)。术后BCVA分析，术后第1d≥0.3的眼数，试验组高于对照组，且差异有统计学意义(P<0.05)，术后1mo，试验组仍高于对照组但差异无统计学意义(P=0.11)。术后1mo，两组ECC值均显著低于术前，试验组与对照组较术前减少近15%～30%，试验组与对照组的角膜内皮丢失率比较差异有统计学意义(P<0.05)。

结论：硬核白内障手术中采用同轴微小切口扭动模式超声效率高，可以显著减少超声能量，有效缩短超声乳化时间，减少了灌注液的应用，降低术后角膜内皮细胞丢失率，促进视力的迅速恢复。

METHODS: It was a prospective and randomized clinical trial. A total of 209 eyes(209 cases)with grade 4 nuclear cataract were randomly assigned into either ozil torsional mode coaxial or conventional group(104 eyes)to undergo microphaco. Best-corrected visual acuity(BCVA), intraocular pressure(IOP), central anterior chamber depth(ACD), endothelial cell count(ECC)before operation and cumulative dissipated energy(CDE), esstimated fluied used(EFU)in operation and complications were recorded. BCVA, IOP, ACD and ECC at 1 day, 1 week, 1 month after operation were compared and statistically analyzed.

RESULTS: The values of BCVA, IOP, ACD and ECC of experimental group were lower than those of conventional group before operation, there was no statistically significant differences(P>0.05). The values of CDE and EFU in ozil torsional mode coaxial group were less than that in the conventional group. The differences among two groups had statistical significance(P<0.05). The BCVA after the operation were improved in both groups, the ozil torsional mode coaxial group were better than the conventional group with the differences of BCVA≥0.3 at 1 day after operation(P=0.11). The ECC at 1 month after operation of two groups was obviously reduced(15%-30%)with a statistically significant difference in the degree of reduction.(P<0.05).

CONCLUSION: The anterior chamber stability was better in ozil torsional mode coaxial microphacoemulsification for hard nuclear cataract, with a significant reduction in the ultrasonic energy and the phaco time. The method can reduce the amount of fluid used in operation, with less ECC loss after operation, which can promote the rapid recovery of vision.