Multifocal Intraocular Lenses: Neuroadaptation Failure Corrected by Exchanging with a Different Multifocal Intraocular Lens

Although intraocular lenses (IOLs) have been explanted for decades, the explantation of multifocal (MF) IOLs has been an increasing recent phenomenon. MF IOLs are explanted because patients complain of dysphotopsias and blurred vision associated in some cases to posterior capsule opacification (PCO) and refractive error that can be easily managed with YAG-capsulotomy, spectacles, and keratorefractive surgery. However, we lack effective treatments for subjective complaints especially the feeling of inadequate or poor vision as well as photic phenomena experienced with both refractive and diffractive MF IOL models. New reports proved that cortical neural areas are responsible for the long-term adaptation to such visual symptoms, suggesting that their persistence is a neuroadaptation failure. Eventually, the only solution in such cases would be the explantation of the MF IOL. The studies available in the literature report the outcomes of MF IOLs exchange to monofocal IOLs, though no relevant investigation was carried out on the exchange of MF IOLs to another MF IOL technologies. Our group is conducting such a study where MF IOLs were explanted due to neuroadaptation failure followed by the re-implantation of a different MF optical technology based on the hypothesis that there may be different neuroadaptation processes for refractive and diffractive IOLs in different patients. Into neuroadaptation failure we included all the subjective visual symptoms that did not have any clear anatomical cause such as photic phenomena, blurred vision, insufficient vision, and monocular diplopia. We had excellent results with an increase in both far and near visual acuities and improvement of patients’ quality of life and vision assessed by validated questionnaires. This procedure showed to be feasible and able to correct the patient’s dissatisfaction and keep the advantages of MF IOLs such as spectacle independence in the benefit of the patient.