The influence of phacoemulsification incision decided by corneal topography on postoperative astigmatism

Objective To observe the influence of phacoemulsification incision decided by corneal topography system on postoperative astigmatism prospectively. Methods 70 eyes underwent phacoemulsification with corneal incision were randomly divided into two groups: group A(incision at the steepest corneal meridian decided by corneal topography and group B(incision at the superior).The changes of corneal astigmatism before and after operation were compared as well as visual acuity. Results The actual members were 56 patients(61 eyes)because of failure of follow-up.Group A had 28 patients(31 eyes) and group B had 28 patients(30 eyes).The astigmatism were(1.13+0.12)D,(1.52±0.13)D,(1.38±0.10)D,(1.22±0.13)D before and 1 week,1 month,3 months after operation respectively in group A.Both the latter two showed no difference compared with the first one(P0.05).In group B,the astigmatism(1.00+0.14)D,(1.99±0.15)D,(1.62±0.14)D,(1.36±0.15)D respectively.Only the last one showed no difference compared with the first one(P0.05).The changes of astigmatism were (0.45±0.18)D,(0.27±0.14)D and(0.11±0.13)D 1 week,1 month,3 rmonths after operation respectively in group A,while (0.98±0.16)D,(0.16±0.12)D,(0.44±0.08)D in group B.The difference were statistically significant(P0.05).There were 11 and 14 eyes obtained visual acuity to better than 0.7 for 1 month and 3 months after operation,while 4 and 6 in group B(P0.05). Conclusions The incision at the steepest corneal meridian decided by corneal topography can reduce postoperative,astigmatism and help visual acuity to recover.