Design and 3-D Print a Subject – Specific Human Spinal Cord

• Kimberly Jacob-Paredes
• Gavin Enderlin
• Ameen Kishta
• Brandon Donaldson
• Caleb Gardner

An anatomically accurate and physically similar in vitro model of the human spinal cord and surrounding tissue, dura, arachnoid, and pia mater, is necessary for studying the relatively unknown dynamics of intrathecal drug delivery. Current methods of study include computer models and in vivo, animal and human, models. Attempts at creating an in vitro model have been made, but the geometric complexity of the spinal cord and surrounding tissue, limitations from available 3D printers, and material properties pose a challenge. Using magnetic resonance images of a subject-specific spinal cord, computer aided design software, fused deposition modeling 3D printers, and both additive and subtractive materials, we have successfully created a manufacturing process. Our process takes an MRI image and creates a negative mold of the spinal cord and surrounding tissue in solidworks that will be printed out with a water soluble, polyvinyl alcohol. The mold is then used to cast the spinal cord and surrounding tissue with a silicone that has similar properties to that of the tissue found in the human body. After curing, the water soluble mold is then left in a water bath, which leaves us with the final product.