Ramin Javan MD, Presenter: Nothing to Disclose

Asim F. Choudhri MD, Abstract Co-Author: Nothing to Disclose

Sina Kalikias MD, Abstract Co-Author: Nothing to Disclose

Jenny K. Hoang MBBS, Abstract Co-Author: Research support, General Electric Company

The fundamental purpose of a 3D printer is to quickly transform an idea into a physical object. The complex neuroanatomy of the cranial nerves may better be understood and depicted by the use of highly customizable advanced 3D printed models.

Cross-sectional imaging has dramatically evolved in the past few decades; especially with evolution of multi- detector computed tomography (MDCT) and Magnetic Resonance Imaging (MRI). Steady-state free precession (SSFP) MRI can demonstrate details down to the cranial nerve level. High-resolution three-dimensional (3D) visualization can now quickly be performed at the workstation. However, we are still limited by visualization on flat screens. An emerging technology, called rapid prototyping or 3D printing, overcomes this limitation.

An actual high-resolution SSFP-MRI of the brain was used to three-dimensionally reconstruct a model of the cranial nerves III-XII as they exit the brainstem. Materialise Mimics 10.0 was used for performing the initial 3D reconstruction, after manually perfecting the segmentation of each cranial nerve anatomy on each thin slice of the scan. Autodesk 3D Studio Max 9.0 was then used to enhance and modify the 3D model’s design. This model was then scaled to a larger size for allowing subsequent 3D printing through a commercially available service utilizing rapid prototyping technology on steel material with minimum detail of 1 mm. This model conforms to a 3D printed model of the bony skull base reconstructed from MDCT data, which contains spaces and neuroforamina that allow passage of the cranial nerves.

Rapid prototyping has become an innovative method of fast and cost-effective production of 3D models for manufacturing. It comprises a variety of automated manufacturing techniques such as selective laser sintering, stereolithography, and three-dimensional printing, which use virtual 3D data sets to fabricate solid forms in a layer-by-layer technique. The idea behind this technique is not new and has been around for many years. However, the types of material that can be used, the level of detail as well as the reduction in costs, have led to significant improved applicability of this concept.

Javan, R, Choudhri, A, Kalikias, S, Hoang, J, Nerves of Steel: 3D Printing of the Cranial Nerves from Steady-State Free Precession MRI.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12021476.html