Rapid Prototyping (RP) is a technique used in industry for manufacturing prototypes. Its capability to physically reproduce geometrical complex shapes is getting increasing interest in many fields of medicine. In the field of vascular surgery, replicas of artery lumen have utility in complex cases or when standard imaging is felt to be equivocal. Replicas can also facilitate experimental studies of computational vascular fluid-dynamics permitting in-vitro reproductions of blood flow in living subjects before and after surgery.
The VIrtual VAscular (VIVA) project at CRS4, developed a system able
to process three-dimensional (3D) datasets extracted from a Computer
Tomography (CT) apparatus, visualize them, reconstruct the geometry of arteries of specific patients, and simulate blood flow in them. In
this paper, the applicability of RP techniques to VIVA's real size
replicas of an autoptic carotid vessel lumen is presented and an
overview of the RP based system developed is provided. The techniques
used in our prototype are discussed and experimental results for the
creation of a human carotid lumen replica are analyzed.
We discuss in detail the pipeline of manufacturing process: 3D
geometric reconstruction from segmented points, geometry tessellation, STL (Stereo Lithography format) conversion. Moreover we
illustrate some technical details of the specific RP technique used to build the lumen replicas, which is called Fused Deposition Modelling (FDM), the materials used for prototypes, throughput time and costs of the FDM models realized.
The system is totally based on open-source software. This enables us
to control each step of the pipeline, from data acquisition to STL
export file. In this context, we present main sources of error
encountered during all manufacturing process stages.