title: Rapid prototyping raw models on the basis of high resolution computed tomography lung data for respiratory flow dynamics.
abstract: OBJECTIVE
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Radiology, German Cancer Research Center, INF 280, 69120 Heidelberg, Germany. f.giesel@dkfz.de
authors.forename: Frederik L
authors.initials: FL
authors.lastname: Giesel
authors.forename: Amit
authors.initials: A
authors.lastname: Mehndiratta
authors.forename: Hendrik
authors.initials: H
authors.lastname: von Tengg-Kobligk
authors.forename: A
authors.initials: A
authors.lastname: Schaeffer
authors.forename: Kevin
authors.initials: K
authors.lastname: Teh
authors.forename: E A
authors.initials: EA
authors.lastname: Hoffman
authors.forename: Hans-Ulrich
authors.initials: HU
authors.lastname: Kauczor
authors.forename: E J R
authors.initials: EJ
authors.lastname: van Beek
authors.forename: Jim M
authors.initials: JM
authors.lastname: Wild
mesh_terms: D003198:Computer Simulation; D004867:Equipment Design / Q000379:methods*; D019544:Equipment Failure Analysis; D005260:Female; D006801:Humans; D008168:Lung / Q000033:anatomy & histology* / Q000000981:diagnostic imaging / Q000502:physiology*; D008953:Models, Anatomic; D008954:Models, Biological; D011659:Pulmonary Gas Exchange / Q000502:physiology*; D014057:Tomography, X-Ray Computed / Q000379:methods*; D055815:Young Adult