title: Age dependence of fusion of primary occipital sutures: a radiographic study.
abstract: OBJECTIVE
  When linear lucency is present in the occipital bone on radiographs throughout childhood, differential diagnosis becomes important because some primary sutures are similar to fractures. The authors here chronicled the normal development of ossification centers, sutures, and synchondroses in the chondrocranium by radiographic examination.
  
  
  METHODS
  One hundred and twenty-seven children, aged from newborns to 6 years and without any skull base deformities, were referred to for radiographs of Towne's projection.
  
  
  RESULTS
  In the occipital bone at birth, three primary sutures could be identified. At the age of 0-3 years, occipital and innominate sutures started to fuse, this being complete by 4 years, whereas mendosal sutures persisted until 6 years of age, after which no primary sutures could be seen.
  
  
  CONCLUSIONS
  The complex process of skull base development features a step-wise process sutural closure for which radiographic standards allow differential diagnosis from fractures with judgment of the timing.
authors.affiliation: Department of Neurosurgery, Nagatsuta Kousei Sogo Hospital, 4-23-1 Nagatsuta, Midori, Yokohama, Kanagawa, Japan. nakahara19@hotmail.com
authors.forename: Kuniaki
authors.initials: K
authors.lastname: Nakahara
authors.forename: Satoshi
authors.initials: S
authors.lastname: Utsuki
authors.forename: Satoru
authors.initials: S
authors.lastname: Shimizu
authors.forename: Hideo
authors.initials: H
authors.lastname: Iida
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Miyasaka
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Takagi
authors.forename: Hidehiro
authors.initials: H
authors.lastname: Oka
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Fujii
mesh_terms: D000375:Aging; D002648:Child; D002675:Child, Preschool; D003393:Cranial Sutures / Q000002:abnormalities / Q000000981:diagnostic imaging / Q000254:growth & development; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009777:Occipital Bone / Q000002:abnormalities / Q000000981:diagnostic imaging / Q000254:growth & development; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed