Measurement of corneal aberrations for customisation of intraocular lens asphericity: impact on quality of vision after micro-incision cataract surgery.

Abstract

To compare the quality of vision of patients with customised aspheric intraocular lenses (IOL) versus patients implanted with zero-aberration IOL after a 1.8 mm micro-incision cataract surgery (MICS). Fourty-three eyes were divided into two groups: 17 eyes (reference group) received zero aberration Acri.Smart 46LC and 26 eyes received a customised-aspheric IOL: either aspherical Acri.Smart 36A, generating a -0.18 microm SA compensation equivalent, or zero-aberration Acri.Smart 46LC. IOL asphericity was individually selected according to the corneal spherical aberration (SA) in order to produce a residual ocular SA close to +0.10 microm. Refraction, best-corrected visual acuity (BCVA), contrast sensitivities, ocular wavefront aberrations and objective quality of vision assessment were analysed 6 months after MICS. Postoperative BCVA was similar in both groups (p=0.58). Mesopic contrast sensitivities were significantly better in the custom group at intermediate and high spatial frequencies (p<0.001), while photopic contrast sensitivities were similar. Total SA was significantly lower in the custom group (Z(4)(0)=0.085+/-0.075 vs 0.261+/-0.091 microm, p<0.001), whereas no difference was found in preoperative corneal SA. Modulation transfer function cut-off frequency was higher in the custom group than in the reference group (34.3+/-8.1 vs 23.57+/-8.6 cycles per degree, respectively; p=0.008). Individual selection of IOL asphericity with a preoperative corneal SA measurement allowed control of final ocular SA. Such customisation improves mesopic contrast sensitivity, and leads to better objective quality of vision.