Correction of spherical aberration in post-LASIK cataract patients implanted with light adjustable IOLs

J. Caballero, E. Villegas, L. Hervella, J. Marín, P. Artal
Purpose: Post-LASIK cataract patients implanted with standard IOLs usually present elevated values of spherical aberration (SA). This may affect the quality of vision even when good refractive outcomes are obtained. We corrected SA in myopic post-LASIK patients with aspheric treatments in light adjustable intraocular lenses (LALs). Visual outcomes were compared with patients without SA correction.
Methods: Thirteen eyes of cataract patients who had previous myopic LASIK were implanted with LALs (Calhoun Vision, Pasadena, USA). Two weeks after surgery, the implanted lenses were irradiated with appropriate spatial intensity profiles to correct the patients’ refractive errors (defocus and astigmatism). In addition, five of them received an aspheric light adjustment to induce a controlled amount of negative spherical aberration to compensate for the elevated positive corneal spherical aberration. After the adjustment procedures, two additional photo-lockin treatments were performed. A wavefont sensor was used to control refraction and spherical aberration during the entire adjustment process. Best-corrected and uncorrected distance visual acuity (VA) was measured using a computer-assisted procedure monocularly.
Results: In all eyes after light treatments, the spherical equivalent was within +0.75 and -0.75 D and the cylinder was equal or below 0.75 D. The patients were classified in three groups according to the final SA values (for 4-mm pupil size): 0 – 0.03 microns (G1, five eyes with aspheric adjustment), 0.10 – 0.15 microns (G2, five eyes) and 0.30 – 0.35 microns (G3, three eyes). The mean values of uncorrected VA were 1.04, 0.97
and 0.67 for G1, G2 and G3 groups respectively. The average best corrected VA for each group was 1.36,
0.99 and 0.75 respectively.
Conclusions: We have demonstrated the correction of SA in five post-LASIK cataract patients implanted with LALs. They showed a significant increment in VA as compared with other patients with large values of residual SA. LALs are well suited for post-LASIK cataract patients to primarily refine refractive errors and eventually correcting for the elevated corneal SA.