方法：老年性白内障患者56例78眼，将患者随机分为2组，2.2mm组38眼，3.0mm组40眼，分别行2.2mm同轴微切口白内障超声乳化联合人工晶状体(IOL)植入术及3.0mm常规白内障超声乳化联合IOL植入术，术后1，3mo评价术眼裸眼视力(uncorrected visual acuity，UCVA)、角膜散光、术源性角膜散光(surgically induced astigmatism，SIA)。

结果：术后1mo，2.2mm组角膜散光为0.85±0.42D，3.0mm组角膜散光为1.18±0.37D，两组角膜散光比较有统计学差异(P<0.05)。术后3mo，2.2mm组角膜散光为0.74±0.40D，3.0mm组角膜散光为1.00±0.30D，两组角膜散光比较有统计学差异(P<0.05)。术后1mo和3mo，3.0mm组的SIA大于2.2mm组(P<0.05)，3.0mm组术后1mo平均SIA大于术后3mo平均SIA(P<0.05)，2.2mm组术后1mo和3mo SIA没有统计学差异(P>0.05)。术后UCVA，在术后1mo和3mo，2.2mm组均优于3.0mm组。

结论：2.2mm同轴微切口白内障超声乳化手术后能产生更小的SIA和更好的UCVA。

METHODS: Fifty-six cataract patients(78 eyes)were randomized into two groups: 38 eyes in the 2.2mm incision group and 40 eyes in the 3.0mm group. Torsional phacoemulsification was followed. Corneal astigmatism, SIA and uncorrected distance visual acuity(UCVA)were assessed at 30 and 90 days after cataract surgery.

RESULTS:One month postoperatively, the corneal astigmatism of the 2.2mm group was 0.85±0.42D and the 3.0mm group was 1.18±0.37D. Three months postoperatively, the corneal astigmatism of the 2.2mm group was 0.74±0.40D and the 3.0mm group was 1.00±0.30D. One month and 3 months postoperatively, SIA of the 3.0mm group was greater than SIA of the 2.2mm group(P<0.05). In the 3.0mm group, mean SIA at 1 month was greater than SIA at 3 months(P<0.05), but SIA was similar. There was no statistical significance between the mean SIA between 1 month and 3 months. Postoperative UCVA was better in the 2.2mm group at both 1 month and 3 months postoperatively.

CONCLUSION: 2.2mm micro-incision coaxial phacoemulsification contributed to postoperative corneal astigmatism. When incision size was reduced, SIA was reduced, refractive stabilization was faster and UCVA was better.