title: Computer-assisted shape descriptors for skull morphology in craniosynostosis.
abstract: OBJECTIVE
  Our aim was to develop a novel method for characterizing common skull deformities with high sensitivity and specificity, based on two-dimensional (2D) shape descriptors in computed tomography (CT) images.
  
  
  METHODS
  Between 2003 and 2014, 44 normal subjects and 39 infants with craniosynostosis (sagittal, 29; bicoronal, 10) enrolled for analysis. Mean age overall was 16 months (range, 1-120 months), with a male:female ratio of 56:29. Two reference planes, sagittal (S-plane: through top of lateral ventricle) and coronal (C-plane: at maximum dimension of fourth ventricle), were utilized to formulate three 2D shape descriptors (cranial index [CI], cranial radius index [CR], and cranial extreme spot index [CES]), which were then applied to S- and C-plane target images of both groups.
  
  
  RESULTS
  In infants with sagittal craniosynostosis, CI in S-plane (S-CI) usually was <1.0 (mean, 0.78; range, 0.67-0.95), with CR consistently at 3 and a characteristic CES pattern of two discrete hot spots oriented diagonally. In the bicoronal craniosynostosis subset, CI was >1.0 (mean 1.11; range, 1.04-1.25), with CR at -3 and a CES pattern of four discrete diagonally oriented hot spots. Scatter plots underscored the highly intuitive joint performance of CI and CES in distinguishing normal and deformed states. Altogether, these novel 2D shape descriptors enabled effective discrimination of sagittal and bicoronal skull deformities.
  
  
  CONCLUSIONS
  Newly developed 2D shape descriptors for cranial CT imaging enabled recognition of common skull deformities with statistical significance, perhaps providing impetus for automated CT-based diagnosis of craniosynostosis.
authors.affiliation: Department of Pediatric Neurosurgery, Craniofacial Reforming and Reconstruction Clinic, Yonsei University College of Medicine, Severance Children's Hospital, 50 Yonsei-ro Seodaemun-gu, Seoul, 03722, Korea.
authors.forename: Kyu Won
authors.initials: KW
authors.lastname: Shim
authors.affiliation: Department of Multimedia Engineering, Seoul Women's University, 621 Hwarangro Nowon-gu, Seoul, 01797, Korea.
authors.forename: Min Jin
authors.initials: MJ
authors.lastname: Lee
authors.affiliation: Department of Plastic and Reconstructive Surgery, Konkuk University School of Medicine, 120-1 Neungdong-ro Gwangjin-gu, Seoul, 05030, Korea.
authors.forename: Myung Chul
authors.initials: MC
authors.lastname: Lee
authors.affiliation: Department of Pediatric Neurosurgery, Craniofacial Reforming and Reconstruction Clinic, Yonsei University College of Medicine, Severance Children's Hospital, 50 Yonsei-ro Seodaemun-gu, Seoul, 03722, Korea.
authors.forename: Eun Kyung
authors.initials: EK
authors.lastname: Park
authors.affiliation: Department of Pediatric Neurosurgery, Craniofacial Reforming and Reconstruction Clinic, Yonsei University College of Medicine, Severance Children's Hospital, 50 Yonsei-ro Seodaemun-gu, Seoul, 03722, Korea.
authors.forename: Dong Seok
authors.initials: DS
authors.lastname: Kim
authors.affiliation: Department of Multimedia Engineering, Seoul Women's University, 621 Hwarangro Nowon-gu, Seoul, 01797, Korea. hlhong@swu.ac.kr.
authors.forename: Helen
authors.initials: H
authors.lastname: Hong
authors.affiliation: Department of Plastic and Reconstructive Surgery, Craniofacial Reforming and Reconstruction Clinic, Yonsei University College of Medicine, Severance Hospital, 50 Yonsei-ro Seodaemun-gu, Seoul, 03722, Korea. sgm625@yuhs.ac.
authors.forename: Yong Oock
authors.initials: YO
authors.lastname: Kim
mesh_terms: D002508:Cephalometry / Q000379:methods*; D002648:Child; D002675:Child, Preschool; D003398:Craniosynostoses / Q000473:pathology*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D007223:Infant; D008297:Male; D012886:Skull / Q000473:pathology*; D014057:Tomography, X-Ray Computed / Q000379:methods
keywords: Cranial index; Cranial spectrum; Craniosynostosis; Scaphocephaly severity index; Shape descriptor