title: Measurement of the volume of oral tumors by three-dimensional spiral computed tomography.
abstract: OBJECTIVE
  To determine the precision and accuracy of in vitro measurements of the volume of oral tumors with three-dimensional (3D) spiral computed tomography (CT) and their precision in vivo.
  
  
  METHODS
  Two simulated tumors made of modelling compound mixed with contrast medium were positioned medial to the mandibles of five cadaver heads and examined with subsecond spiral CT. Two observers delineated the simulated tumors twice in axial, coronal and sagittal views and then measured the volume from multiplanar reconstructed images. The software tools automatically displayed the simulated tumors in 3D-reconstructed images with the volumetric measurements. The simulated tumors were removed and their volume measured by water displacement. The volume of 15 oral tumors associated with the mandible were measured in vivo with the same imaging methods and the precision analysed.
  
  
  RESULTS
  There were no statistically significant differences between or within observers or between imaging and physical measurements in vitro, nor between inter- and intra-observer measurements in vivo (P > 0.05).
  
  
  CONCLUSIONS
  Volumetric measurements from 3D-reconstructed CT are reliable and accurate in vitro and reliable in vivo. The method is potentially useful for the management of oral neoplasms.
authors.affiliation: Department of Radiology, Faculty of Odontology, University of São Paulo, São Paulo, Brazil.
authors.forename: M G
authors.initials: MG
authors.lastname: Cavalcanti
authors.forename: M W
authors.initials: MW
authors.lastname: Vannier
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D002102:Cadaver; D003287:Contrast Media; D003626:Data Display; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D015588:Observer Variation; D012984:Software; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media