title: Accuracy of craniofacial measurements: computed tomography and three-dimensional computed tomography compared with stereolithographic models.
abstract: In a retrospective study, distance measurements of nine children with craniofacial malformation were analyzed. The accuracy of measurements was compared when measured on a workstation using a 16-slice multidetector spiral computed tomography and on a stereolithographic model. Three different methods of defining distances were investigated: 1) on the stereolithographic plastic models, 14 distances connecting landmarks were identified with a digitizer (Polaris Tracker); 2) the same distances were defined at axial, coronal, and sagittal reformats of the computed tomography data set and measured using a Philips MX View workstation; and 3) the same 14 distances were defined at three-dimensional virtual reality models of the skulls at the same workstation. All measurements were performed with all three methods by three different readers. The following conclusions could be drawn: stereolithographic models provide a highly exact reproduction of the skull in children with craniofacial malformations. They are a reliable basis for all analytic and probatory endeavors preparing complicated surgical corrections. Three-dimensional virtual reality display modes serve significantly better for exact distance measurements on the complex surface of the human skull than planar reformats of the same computed tomography data sets.
authors.affiliation: Department of Radiology, Division of Osteoradiology, Medical University of Vienna, Austria. Julia@fruehwald.at
authors.forename: Julia
authors.initials: J
authors.lastname: Frühwald
authors.forename: Kurt A
authors.initials: KA
authors.lastname: Schicho
authors.forename: Michael
authors.initials: M
authors.lastname: Figl
authors.forename: Thomas
authors.initials: T
authors.lastname: Benesch
authors.forename: Franz
authors.initials: F
authors.lastname: Watzinger
authors.forename: Franz
authors.initials: F
authors.lastname: Kainberger
mesh_terms: D000168:Acrocephalosyndactylia / Q000175:diagnosis; D002508:Cephalometry / Q000379:methods* / Q000706:statistics & numerical data; D002675:Child, Preschool; D002971:Cleft Lip / Q000175:diagnosis; D002972:Cleft Palate / Q000175:diagnosis; D017076:Computer-Aided Design; D019465:Craniofacial Abnormalities / Q000175:diagnosis*; D003398:Craniosynostoses / Q000175:diagnosis; D005147:Facial Bones / Q000473:pathology; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods* / Q000706:statistics & numerical data; D007223:Infant; D008831:Microcephaly / Q000175:diagnosis; D008953:Models, Anatomic; D015588:Observer Variation; D049068:Plagiocephaly, Nonsynostotic / Q000175:diagnosis; D010969:Plastics; D011873:Radiology Information Systems; D015203:Reproducibility of Results; D012189:Retrospective Studies; D036542:Tomography, Spiral Computed / Q000379:methods* / Q000706:statistics & numerical data; D014584:User-Computer Interface
chemical_list: D010969:Plastics