Longitudinal structural brain changes after Scharioth macula lens implantation in patients with age-related macular degeneration

Background and Purpose Age-related macular degeneration (AMD) is associated with visual impairment and with structural and functional brain changes. The extent to which AMD affects cerebral structure and whether visual rehabilitation, including implantation of the Scharioth macula lens (SML), is associated with structural brain changes, remains incompletely understood. This study aimed to investigate regional brain volume alterations in patients with AMD and to assess longitudinal changes after SML implantation. Materials and Methods Ten patients with AMD (mean age 78.8 ± 5.6 years) underwent a structural brain MRI at 3T before and 6 months after SML implantation. Regional brain volumes were quantified using a fully automated AI-assisted multi-atlas segmentation tool (cNeuro cMRI). The results were expressed as absolute volumes and normative percentile values relative to an age-matched healthy MRI reference database. Primary analyses focused on a predefined extended visual network. In addition, exploratory whole-brain analyses were performed with correction for multiple comparisons. A vision-related quality-of-life questionnaire was administered, and changes in composite scores were associated with pre-implantation volumes. Results At baseline, pronounced atrophy was observed in the posterior visual cortex, most prominently in the occipital pole, and most of the patients showed reduced normative percentiles. Longitudinal analyses revealed overall structural stability in the visual network. Region-specific changes were identified, including significant decreases in percentile values in the left middle occipital gyrus and the precuneus, along with an increase in the volume of the occipital pole and the percentile ranking. Exploratory analyses outside the visual network identified heterogeneous uncorrected changes; however, none survived the false discovery rate correction. Visual quality-of-life composites showed modest mean improvements in 6 months, but no association with volume was statistically significant after correction for multiple comparisons. Conclusions AMD is associated with regionally specific structural alterations in the posterior visual cortex. Following SML implantation and visual rehabilitation, the visual network regions demonstrated general stability with heterogeneous regional changes, while no evidence of generalized brain involvement was observed. These findings support the involvement of central visual pathways in AMD and suggest preserved cortical plasticity even in advanced age.