From MRI to 3D printing: a tangible neuroeducational tool for visualizing hippocampal morphology and Alzheimer's disease progression.

Alzheimer's disease (AD) affects the hippocampus early and profoundly, yet its complex three-dimensional (3D) anatomy can be difficult to appreciate on conventional imaging. Recognizing hippocampal atrophy in amnestic mild cognitive impairment (MCI) is essential for timely diagnosis and clinical decision-making. This study aimed to create a tangible 3D hippocampal model derived from magnetic resonance imaging (MRI) to support neuroeducation, enhance clinician training, and improve visualization of disease-related change. High-resolution T1-weighted MRI scans were obtained from 9 cognitively healthy controls (HC), 10 individuals with MCI, and 10 with AD. Semi-automated segmentation was used to reconstruct 3D hippocampal models for each group. Volumetric analyses assessed hippocampal atrophy, hemispheric asymmetry, and diagnostic differentiation. The hemisphere showing the most pronounced atrophy was selected for physical modeling, and an experienced neurologist reviewed a 3D-printed hippocampus for anatomical accuracy and educational value. Significant volumetric differences were identified in both hippocampal hemispheres across HC, MCI, and AD (p < .001). The right hippocampus demonstrated the greatest atrophy in AD and early volume loss in MCI. Receiver operating characteristic analysis showed strong diagnostic performance, with areas under the curve of 0.980 for AD versus MCI and 0.833 for MCI versus HC. Based on these findings, the right hippocampus was selected for 3D printing. MRI-derived 3D-printed hippocampal models translate complex neuroimaging data into accessible, tactile representations of AD-related degeneration. This approach has potential value for medical education, clinician training, patient-clinician communication, and public awareness, as it makes hippocampal atrophy more clearly visible and understandable.