Date Published: November 21, 2017
Publisher: Springer International Publishing
Author(s): Matthew Marks, Amy Alexander, Joseph Matsumoto, Jane Matsumoto, Jonathan Morris, Ronald Petersen, Clifford Jack, Tatsuya Oishi, David Jones.
Alzheimer’s disease prevalence will reach epidemic proportions in coming decades. There is a need for impactful educational materials to help patients, families, medical practitioners, and policy makers understand the nature and impact of the disease. Defining an effective workflow to create such models from existing segmentation tools will be a valuable contribution in creating these patient-specific models.
A step-by-step workflow was developed and used to take patients’ Digital Imaging and Computing in Medicine magnetic resonance brain images through a process resulting in illustrative 3D–printed brain and hippocampus models that clearly demonstrate the progressive degenerative changes caused by Alzheimer’s disease. We outline the specific technical steps of auto-segmentation, manual smoothing, Standard Triangle Language file customization, and 3D printing used to create these models.
Our explicated workflow can create effective models of Alzheimer’s brains that can be used in patient education, medical education, and policy forums.
Alzheimer’s disease is a neurodegenerative disease causing progressive and disabling cognitive decline. As populations age, the prevalence of Alzheimer’s disease is increasing dramatically. Currently, in the United States, 5.5 million people are afflicted with Alzheimer’s disease, with this number estimated to rise to 15 million by 2050 .
The workflow detailed above resulted in the successful production of models for each of the five representative subjects (Figs. 7, 8, 9, 10 and 11) The loss of total brain volume and cortical atrophy with advancing Alzheimer’s disease and age are clearly represented. The anatomic position of the hippocampus and its complex anatomy are easily appreciated by viewing the opaque hippocampus through the semi-transparent media and breaking the model apart to see the hippocampus exposed within the brain. Hippocampal atrophy is evident with advancing disease and age.Fig. 7Hippocampus STL files and 3D–printed models. Row a: Hippocampal STL files are displayed with increasing disease severity from normal to severe Alzheimer’s disease moving from left to right. Row b: Final printed models corresponding to the normal hippocampus and three stages of Alzheimer’s disease severity and displayed on custom printed stands. Hippocampal size declines with both age and Alzheimer’s disease severity, and the models clearly demonstrate these effects. Radiologically severe model not available for photoFig. 8Normal brain STL files. The final STL files of the normal brain are displayed showing the cutting planes, sectional breakdown and magnet holes. The following STL images in Figs. 7 and 8 and the photographs in Figs. 9 and 10 are all displayed at the same scale, so the contrast in size between the normal and severe Alzheimer’s brains pictured here is representative of the disparity displayed by the physical models themselvesFig. 9Alzheimer’s brain STL files. The final STL files for the clinically severe (Severe-1) Alzheimer’s brainFig. 10Normal brain 3D–printed model. Photographs are from an early prototype of the normal brain that included labels for the left and right hemispheres, which were omitted in all subsequent models. This particular model was photographed after only several magnets were attached and prior to application of the clear coat sprayFig. 11Alzheimer’s brain 3D–printed model. Photographs of the clinically severe (Severe-1) Alzheimer’s brain. Photographs were taken after all magnets were attached and after application of the clear coat spray
The workflow described in detail here produces life-sized, individualized brain and hippocampal models in subjects with Alzheimer’s disease or other neurologic conditions. 3D–printed models have demonstrated significant educational value in other medical specialties. When 3D–printed models were used during consultation for pediatric patients with congenital heart disease, the patients’ parents and the cardiologists both rated the usefulness of the models very highly and believed they improved communication during the consultation .
The rising epidemic of Alzheimer’s disease requires educational materials that will increase awareness, facilitate understanding, and stimulate action. We believe that 3D–printed brain models using the workflow explained here are ideal for this purpose.