Rationale and objectives: Three-dimensional image reconstruction by volume rendering and rapid prototyping has made it possible to visualize anatomic structures in three dimensions for interventional planning and academic research.
Methods: Volumetric chest computed tomography was performed on a healthy volunteer. Computed tomographic images of the larger bronchial branches were segmented by an extended three-dimensional region-growing algorithm, converted into a stereolithography file, and used for computer-aided design on a laser sintering machine. The injection of gases for respiratory flow modeling and measurements using magnetic resonance imaging were done on a hollow cast.
Results: Manufacturing the rapid prototype took about 40 minutes and included the airway tree from trackea to segmental bronchi (fifth generation). The branching of the airways are clearly visible in the (3)He images, and the radial imaging has the potential to elucidate the airway dimensions.
Conclusion: The results for flow patterns in the human bronchial tree using the rapid-prototype model with hyperpolarized helium-3 magnetic resonance imaging show the value of this model for flow phantom studies.