AIM:To research clinical effect of two manual chopping methods for small incision extracapsular cataract extraction.

METHODS: We observed 143 cases(184 eyes)with grade Ⅳ or higher taken the small incision cataract extraction and intraocular lens implantation. Patients were given randomly knifed chopping with closed hook(92 eyes)or double knifed chopping(92 eyes). The intra-operative posterior capsule rupture was observed and compared. At 1d, 1wk and 1mo postoperatively, visual acuity, corneal edema and corneal astigmatism were observed and analyzed.

RESULTS:There were 10 eyes in patients accepting knifed chopping with closed hook with intra-operative posterior capsule rupture and 1 eye in patients accepting double knifed chopping. The difference between the two groups was statistically significant. The visual acuity of patients accepting knifed chopping with closed hook(92 eyes)at 1d postoperatively was 0.380±0.105, and that of patients accepting double knifed chopping(92 eyes)was 0.420±0.095; the difference between the two groups was statistically significant. The visual acuity of patients accepting knifed chopping with closed hook(84 eyes)at 1wk postoperatively was 0.480±0.123, and that of patients accepting double knifed chopping(86 eyes)was 0.520±0.085; the difference between the two groups was statistically significant. The visual acuity of patients accepting knifed chopping with closed hook(60 eyes)at 1mo postoperatively was 0.610±0.083, and that of patients accepting double knifed chopping(52 eyes)was 0.643±0.072; the difference between the two groups was not statistically significant. The differences on corneal edema and corneal astigmatism between the two methods at 1d, 1wk and 1mo postoperatively were not statistically significant.

CONCLUSION:The application of knifed chopping with closed hook and double knifed chopping in small incision extracapsular cataract extraction and intraocular lens implantation can effectively treat with cataract with grade Ⅳ or higher. The most important difference is on the capsular rupture which causes the different recover periods after the two operations. There was no significant difference on postoperative corneal edema and astigmatism.