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Purpose: To evaluate the use of functional magnetic resonance imaging (MRI) to assess neuroadaptation to multifocal intraocular lenses (IOLs)., Setting: Faculty of Medicine, University of Coimbra, Coimbra, Portugal., Design: Prospective case study., Methods: Patients with bilateral diffractive IOL implantation after cataract surgery had functional MRI at postoperative intervals of 3 weeks and 6 months. A nonintervention control group was included as proof of concept. Functional stimuli consisted of sinusoidal gratings with threshold contrast and a light source to induce disability glare. Subjective quality of vision and reading performance were assessed and wavefront analyses were performed., Results: The study comprised 30 patients in the study group and 15 in the control group. Glare decreased the functional MRI signal measured for sinusoidal gratings initially (3 weeks) but not at 6 months (P = .04), which was confirmed by contrast detection under glare improvement (P = .002). Patients showed increased activity of cortical areas involved in visual attention, procedural learning, effortful cognitive control, and goal-oriented behavior in the early postoperative period, which normalized at 6 months. There were no differences in aberrations, Strehl ratio, or modulation transfer function despite significant decreases in questionnaire symptom scores and visual acuity and reading performance improvements. The control group remained unchanged., Conclusions: Neuroadaptation to multifocal IOLs took place initially through recruitment of visual attentional and procedural learning networks. Thereafter, a form of long-term adaptation/functional plasticity occurred, leading to brain activity regularization toward a non-effort pattern. These findings, which reinforce the crucial role of higher-level brain regions in the perceptual construction of vision, were consistent with functional and questionnaire outcomes and were unrelated to optical properties., (Copyright © 2017 ASCRS and ESCRS. All rights reserved.)

Purpose: To investigate the association between dysphotopsia and neural responses in visual and higher-level cortical regions in patients who recently received multifocal intraocular lens (IOL) implants., Design: Cross-sectional study., Participants: Thirty patients 3 to 4 weeks after bilateral cataract surgery with diffractive IOL implantation and 15 age- and gender-matched control subjects., Methods: Functional magnetic resonance imaging (fMRI) was performed when participants viewed low-contrast grating stimuli. A light source surrounded the stimuli in half of the runs to induce disability glare. Visual acuity, wavefront analysis, Quality of Vision (QoV) questionnaire, and psychophysical assessment were performed., Main Outcome Measures: Cortical activity (blood oxygen level dependent [BOLD] signal) in the primary visual cortex and in higher-level brain areas, including the attention network., Results: When viewing low-contrast stimuli under glare, patients showed significant activation of the effort-related attention network in the early postoperative period, involving the frontal, middle frontal, parietal frontal, and postcentral gyrus (multisubject random-effects general linear model (GLM), P < 0.03). In contrast, controls showed only relative deactivation (due to lower visibility) of visual areas (occipital lobe and middle occipital gyrus, P < 0.03). Patients also had relatively stronger recruitment of cortical areas involved in learning (anterior cingulate gyrus), task planning, and solving (caudate body). Patients reporting greater symptoms induced by dysphotic symptoms showed significantly increased activity in several regions in frontoparietal circuits, as well as cingulate gyrus and caudate nucleus (q < 0.05). We found no correlation between QoV questionnaire scores and optical properties (total and higher order aberration, modulation transfer function, and Strehl ratio)., Conclusions: This study shows the association between patient-reported subjective difficulties and fMRI outcomes, independent of optical parameters and psychophysical performance. The increased activity of cortical areas dedicated to attention (frontoparietal circuits), to learning and cognitive control (cingulate), and to task goals (caudate) likely represents the beginning of the neuroadaptation process to multifocal IOLs., (Copyright © 2017 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)