RESUMO
PURPOSE: To analyze the effectiveness of laser in situ keratomileusis (LASIK) and arcuate keratotomy (AK) to treat simple myopic, compound myopic, and mixed astigmatism. SETTING: Instituto de la Visión, Buenos Aires, Argentina. METHODS: This retrospective nonrandomized study comprised 821 cases treated with LASIK and 46 cases treated with AK. Patients were divided into 4 groups, which had the following preoperative cylinder corrections: simple myopic astigmatism (Group 1) (LASIK: n = 76, -3.91 diopters [D] +/- 1.29 [SD]; AK: n = 5, -3.85 +/- 0.65 D); compound myopic astigmatism up to 2.00 D (Group 2) (LASIK: n = 401, -1.69 +/- 0.76 D; AK: n = 14, -1.48 +/- 0.41 D); compound myopic astigmatism over 2.00 D (Group 3) (LASIK: n = 253, -3.61 +/- 0.89 D; AK: n = 16, -3.09 +/- 0.84 D); mixed astigmatism (Group 4) (LASIK: n = 91, +3.65 +/- 1.62 D; AK: n = 11, 4.39 +/- 0.92 D). RESULTS: Six months postoperatively, the cylinder's vector-corrected change was as follows: Group 1, LASIK 3.75 +/- 1.08 D, AK 3.16 +/- 0.84 D; Group 2, LASIK 1.55 +/- 1.12 D, AK 1.34 +/- 0.44 D; Group 3, LASIK 3.39 +/- 0.98 D, AK 2.70 +/- 1.21 D; Group 4, LASIK 3.77 +/- 1.43 D, AK 3.75 +/- 0.89 D. Respective mean uncorrected visual acuities in each group were as follows: Group 1, 0.71 +/- 0.12 and 0.60 +/- 0.12; Group 2, 0.83 +/- 0.12 and 0.78 +/- 0.24; Group 3, 0.78 +/- 0.18 and 0.48 +/- 0.24; Group 4, 0.69 +/- 0.21 and 0.55 +/- 0.18. CONCLUSIONS: The vector-corrected change and visual acuity achieved with LASIK were better, although not significantly, than those attained with AK except for the UCVA obtained with LASIK in eyes with compound myopic astigmatism over 2.00 D. Both methods proved to be safe.