title: Three-dimensional cephalometric analysis of adolescents with cleft lip and palate using computed tomography-guided imaging.
abstract: OBJECTIVE
  To propose landmarks and a new coordinate system to aid three-dimensional cephalometric analysis of adolescent cleft lip and palate (CLP) using computed tomography (CT) imaging.
  
  
  METHODS
  Sixty-four-row CT images obtained from 52 adolescent patients were retrospectively analyzed with the MIMICS program (MIMICS 10.02; Materialise Technologies, Leuven, Belgium) to determine intrarater reliability of new landmarks for three-dimensional cephalometric analysis before surgery.
  
  
  RESULTS
  Five points were located on each image including the midpoint between both uppermost external points of the external auditory meatus (EAM), the center of the sella turcica (sella, S), the most anterior point on the nasofrontal suture in the midline (nasion, N), and the right and left lowest points of the lower edge of the orbitale (r/l orbitale, r/l Or). The horizontal reference plane was then determined using EAM and bilateral Or. The sagittal reference plane was defined perpendicular to the horizontal plane, passing through N and S. The coronal reference plane included the EAM landmark and was perpendicular to the sagittal and horizontal planes. All 5 points had high intrarater reliability and proved easy to use in constructing the new coordinate system. The horizontal, sagittal, and coronal reference planes formed by these respective points improved the ease of performing three-dimensional cephalometric analysis of CLP adolescents with CT imaging.
  
  
  CONCLUSIONS
  Our 5 landmarks provided reliable CT-guided three-dimensional cephalometric analysis of CLP, allowing for accurate quantitative assessment in adolescents before orthognathic surgery.
authors.affiliation: From the *Plastic Surgery Hospital, Chinese Academy of Medical Science, Peking Union Medical College, Beijing; and †School of Nursing, ‡Department of Aesthetic, Plastic and Burn Surgery, Shandong Provincial Hospital, and §School of Medicine, Shandong University, Jinan, Shandong, China.
authors.forename: Zhen-min
authors.initials: ZM
authors.lastname: Zhao
authors.forename: Yun
authors.initials: Y
authors.lastname: Zhu
authors.forename: Ran
authors.initials: R
authors.lastname: Huo
authors.forename: Jing-ran
authors.initials: JR
authors.lastname: Su
authors.forename: Feng
authors.initials: F
authors.lastname: Gao
mesh_terms: D000293:Adolescent; D059925:Anatomic Landmarks / Q000000981:diagnostic imaging; D002508:Cephalometry / Q000379:methods* / Q000706:statistics & numerical data; D002971:Cleft Lip / Q000000981:diagnostic imaging*; D002972:Cleft Palate / Q000000981:diagnostic imaging*; D004424:Ear Canal / Q000000981:diagnostic imaging; D005260:Female; D005624:Frontal Bone / Q000000981:diagnostic imaging; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods* / Q000706:statistics & numerical data; D008297:Male; D009295:Nasal Bone / Q000000981:diagnostic imaging; D015588:Observer Variation; D009915:Orbit / Q000000981:diagnostic imaging; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012658:Sella Turcica / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed / Q000379:methods* / Q000706:statistics & numerical data