AIM: To evaluate the differences between Haigis-L formula and CH-SRK/T when predicting intraocular lens power after laser in situ keratomileusis(LASIK)surgery for myopia.

METHODS: Seventy-two patients(140 eyes, axial length ≤26mm)after LASIK surgery were recruited between October 2012 and February 2013. Participants with other ophthalmic diseases were excluded. Haigis-L and CH-SRK/T formula were used to calculate the intraocular lens power separately after LASIK surgery and the data were analyzed using SPSS 18.0 software.

RESULTS: The mean value of Hoyaintraocular lens after LASIK was 22.99±1.38D by Haigis-L formula compared with 19.95±1.69D using CH-SRK/T formula. According to paired t-test, pairs of differential mean are -3.039±1.899D. Wilcoxon signed rank test was used and the sum of ranks was -3.408^a(P=0.001). Meanwhile, the mean value of Allergan AR40 intraocular lens was 23.26±1.49D by Haigis-L formula; while the degree of intraocular lens calculated by CH-SRK/T formula was 20.05±1.69D. According to paired t-test, pairs of differential mean are -3.208±1.823D. Wilcoxon signed rank test was used and the sum of ranks was -3.408^a(P=0.001).

CONCLUSION: After LASIK surgery for myopia, the degree of intraocular lens power measured by CH-SRK/T is lower than that by Haigis-L formula. The degree of intraocular lens power calculated by CH-SRK/T is more likely to be under corrected.