Influence of the incisions of cataract surgery on corneal aberrations

Resumo

The aim of this work is to study the effects produced by 1 incision and paired incisions in corneal aberrations after cataract surgery. We selected 21 eyes of 18 patients aged between 44 and 89 years (69,81 ± 12.55). Aberrations were measured by corneal topographer Sirius 5 eyes with incisions paired (3 mm) and 16 eyes 1 corneal incision (2.2 mm). Data of topography, RMS values, and Zernike coefficients to 4th order were obtained a week before and 3-4 weeks after surgery for a pupil diameter of 6 mm. Corneal astigmatism was reduced with paired incisions (pre 0.94 ± 0.44 D, post 0.90 ± 0.48 D) (P =0.26) and increased with an incision (pre 1.29 ± 1.28 D, post 1.34 ± 1.45 D) (P = 0.77) Although differences were no statistically significant. The total RMS average increased with paired incisions (pre 1.16 ± 0.39 µm, post 1.24 ± 0.34 µm) (P = 0.46) and decreased with an incision (pre 1.76 ± 1.47 µm and post 1.54 ± 1.58 µm) (P = 0.91) after surgery. Higher order aberrations increased with paired incisions and decreased with 1 incision. The comma (pre 0.40 ± 0.19 µm, post 0.40 ± 0.30 µm) with paired incisions and spherical aberration (pre 0.31 ± 0.24 µm, post 0.31 ± 0.18 µm) with 1 incision showed no change post-surgical. These two types of incisions, although they induce changes after cataract surgery in aberrations corneal as clover, coma, astigmatism, tetrafoil, secondary astigmatism and spherical aberration, not impaired significantly the optical quality of the corneal surface.