title: Validation of computational fluid dynamics in CT-based airway models with SPECT/CT.
abstract: OBJECTIVE
  To compare the results obtained by using numerical flow simulations with the results of combined single photon emission computed tomography (SPECT) and computed tomography (CT) and to demonstrate the importance of correct boundary conditions for the numerical methods to account for the large amount of interpatient variability in airway geometry.
  
  
  METHODS
  This study was approved by all relevant institutional review boards. All patients gave their signed informed consent. In this study, six patients with mild asthma (three men; three women; overall mean age, 46 years ± 17 [standard deviation]) underwent CT at functional residual capacity and total lung capacity, as well as SPECT/CT. CT data were used for segmentation and computational fluid dynamics (CFD) simulations. A comparison was made between airflow distribution, as derived with (a) SPECT/CT through tracer concentration analysis, (b) CT through lobar expansion measurement, and (c) CFD through flow computer simulation. Also, the heterogeneity of the ventilation was examined.
  
  
  RESULTS
  Good agreement was found between SPECT/CT, CT, and CFD in terms of airflow distribution and hot spot detection. The average difference for the internal airflow distribution was less than 3% for CFD and CT versus SPECT/CT. Heterogeneity in ventilation patterns could be detected with SPECT/CT and CFD.
  
  
  CONCLUSIONS
  This results of this study show that patient-specific computer simulations with appropriate boundary conditions yield information that is similar to that obtained with functional imaging tools, such as SPECT/CT.
  
  
  BACKGROUND
  http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.10100322/-/DC1.
authors.affiliation: FluidDA, Groeningenlei 132, 2550 Kontich, Belgium. Jan.DeBacker@FluidDA.com
authors.forename: Jan W
authors.initials: JW
authors.lastname: De Backer
authors.forename: Wim G
authors.initials: WG
authors.lastname: Vos
authors.forename: Samir C
authors.initials: SC
authors.lastname: Vinchurkar
authors.forename: Rita
authors.initials: R
authors.lastname: Claes
authors.forename: Anton
authors.initials: A
authors.lastname: Drollmann
authors.forename: Denis
authors.initials: D
authors.lastname: Wulfrank
authors.forename: Paul M
authors.initials: PM
authors.lastname: Parizel
authors.forename: Paul
authors.initials: P
authors.lastname: Germonpré
authors.forename: Wilfried
authors.initials: W
authors.lastname: De Backer
mesh_terms: D000328:Adult; D000336:Aerosols / Q000008:administration & dosage; D000368:Aged; D001249:Asthma / Q000000981:diagnostic imaging* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008953:Models, Anatomic; D011857:Radiographic Image Interpretation, Computer-Assisted; D019275:Radiopharmaceuticals / Q000008:administration & dosage; D012129:Respiratory Function Tests; D012984:Software; D016284:Technetium Tc 99m Pentetate / Q000008:administration & dosage; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed
chemical_list: D000336:Aerosols; D019275:Radiopharmaceuticals; D016284:Technetium Tc 99m Pentetate