To investigate cognitive, structural, and blood–brain barrier (BBB) changes associated with cataract surgery in older adults, exploring visual restoration as a modulator of neurovascular and cognitive function.

Visual impairment is a known modifiable risk factor for cognitive decline, yet its neurophysiological mechanisms remain unclear. Cataracts, the most common and treatable cause of vision loss in aging, offer an ideal model to examine how sensory deprivation and its reversal affect cognition, brain structure, and BBB integrity.

Eighteen participants (≥60 years) with bilateral cataracts completed assessments at baseline (pre-surgery) and at three and nine months following bilateral cataract surgery. Cognitive performance (RBANS-U), ophthalmological measures, and MRI data were obtained at each visit. BBB permeability was quantified from DCE-MRI Ktrans values and regional leakage percentiles, while volumetric and cortical-thickness analyses used the volBrain platform. Longitudinal changes were analyzed with linear mixed-effects models.

Baseline assessment showed the lowest performance in attention and delayed memory. Over follow-up,  all domains improved significantly (p < 0.05), with the largest gains in immediate and delayed memory: percentiles rose from 43.0 ± 29.2 to 68.2 ± 32.0 and 51.9 ± 34.7 to 65.1 ± 31.8, respectively. Cognitive gains paralleled better visual acuity and contrast sensitivity. Elevated occipital Ktrans values were present in 61% at baseline and showed near-complete resolution after surgery. Post-surgical analyses revealed reduced BBB permeability in hippocampi and subcortical gray and white matter, increased cortical thickness in temporal, occipital, and parietal regions, and a ≈0.8-year deceleration in brain aging after surgery.

Visual restoration was associated with cognitive improvement, BBB normalization, and structural recovery. This unique longitudinal study integrates BBB and volumetric MRI analyses, revealing cortical and subcortical changes in memory and associative regions, supporting that timely sensory correction fosters neurovascular stability, plasticity, and cognitive resilience in aging.