title: Image fusion in craniofacial virtual reality modeling based on CT and 3dMD photogrammetry.
abstract: OBJECTIVE
  The aim of this study was to demonstrate the feasibility of building a craniofacial virtual reality model by image fusion of 3-dimensional (3D) CT models and 3 dMD stereophotogrammetric facial surface.
  
  
  METHODS
  A CT scan and stereophotography were performed. The 3D CT models were reconstructed by Materialise Mimics software, and the stereophotogrammetric facial surface was reconstructed by 3 dMD patient software. All 3D CT models were exported as Stereo Lithography file format, and the 3 dMD model was exported as Virtual Reality Modeling Language file format. Image registration and fusion were performed in Mimics software. Genetic algorithm was used for precise image fusion alignment with minimum error. The 3D CT models and the 3 dMD stereophotogrammetric facial surface were finally merged into a single file and displayed using Deep Exploration software. Errors between the CT soft tissue model and 3 dMD facial surface were also analyzed.
  
  
  RESULTS
  Virtual model based on CT-3 dMD image fusion clearly showed the photorealistic face and bone structures. Image registration errors in virtual face are mainly located in bilateral cheeks and eyeballs, and the errors are more than 1.5 mm. However, the image fusion of whole point cloud sets of CT and 3 dMD is acceptable with a minimum error that is less than 1 mm.
  
  
  CONCLUSIONS
  The ease of use and high reliability of CT-3 dMD image fusion allows the 3D virtual head to be an accurate, realistic, and widespread tool, and has a great benefit to virtual face model.
authors.affiliation: From the *Department of Oral and Craniomaxillofacial Surgery, Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai 200011; and †Institute of CIM, Shanghai Jiao Tong University, Shanghai Key Laboratory of Advanced Manufacturing Environment, Shanghai 200030, People's Republic of China.
authors.forename: Pengfei
authors.initials: P
authors.lastname: Xin
authors.forename: Hongbo
authors.initials: H
authors.lastname: Yu
authors.forename: Huanchong
authors.initials: H
authors.lastname: Cheng
authors.forename: Shunyao
authors.initials: S
authors.lastname: Shen
authors.forename: Steve G F
authors.initials: SG
authors.lastname: Shen
mesh_terms: D003198:Computer Simulation; D019465:Craniofacial Abnormalities / Q000175:diagnosis*; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods*; D064847:Multimodal Imaging / Q000379:methods*; D010780:Photogrammetry; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012984:Software; D014057:Tomography, X-Ray Computed; D014584:User-Computer Interface; D055815:Young Adult