title: Differential closure of the spheno-occipital synchondrosis in syndromic craniosynostosis.
abstract: BACKGROUND
  The spheno-occipital synchondrosis is a driver of cranial base and facial growth. Its premature fusion has been associated with midface hypoplasia in animal models. The authors reviewed computed tomographic scans of patients with Apert and Muenke syndrome, craniosynostosis syndromes with midface hypoplasia, to assess premature fusion of the spheno-occipital synchondrosis when compared with normal controls.
  
  
  METHODS
  Ninety head computed tomographic scans of Apert syndrome patients and 31 head scans of Muenke syndrome patients were assessed, in addition to an equal number of control scans. Spheno-occipital synchondrosis fusion on axial images was graded as open, partially closed, or closed. Analysis focused on ages 7 to 14 years, as no control patient fused before age 7 or had failed to fuse after age 14.
  
  
  RESULTS
  All 38 Apert syndrome patients aged 7 to 14 had some degree of spheno-occipital synchondrosis closure, compared with 29 of 38 matched controls (p = 0.0023). Seventeen of 20 Muenke syndrome patients showed closure, compared with 14 of 20 matched controls (p = 0.4506). Partial fusion was seen as early as age 2 in Apert syndrome and age 6 in Muenke syndrome patients; the earliest fusion was seen at age 7 in the control group.
  
  
  CONCLUSIONS
  Compared with matched controls, the spheno-occipital synchondrosis closes significantly earlier in patients with Apert syndrome but not Muenke syndrome. This correlates well to reported incidences of midface hypoplasia in these syndromes. Although causality cannot be concluded from this study, an association exists between midface phenotype and degree of spheno-occipital synchondrosis closure.
  
  
  METHODS
  Risk, II.
authors: Philadelphia, Pa.; Dallas, Texas; and New Haven, Conn. From the Department of Surgery, Perelman School of Medicine, University of Pennsylvania; University of Texas Southwestern Medical Center; Yale University School of Medicine; and the Department of Radiology and the Division of Plastic and Reconstructive Surgery, The Children's Hospital of Philadelphia.
authors: Jennifer
authors: J
authors: McGrath
authors: Patrick A
authors: PA
authors: Gerety
authors: Christopher A
authors: CA
authors: Derderian
authors: Derek M
authors: DM
authors: Steinbacher
authors: Arastoo
authors: A
authors: Vossough
authors: Scott P
authors: SP
authors: Bartlett
authors: Hyun-Duck
authors: HD
authors: Nah
authors: Jesse A
authors: JA
authors: Taylor
mesh_terms: D000168:Acrocephalosyndactylia / Q000601:surgery; D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003398:Craniosynostoses / Q000503:physiopathology* / Q000601:surgery*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009777:Occipital Bone / Q000254:growth & development*; D012189:Retrospective Studies; D013100:Sphenoid Bone / Q000254:growth & development*; D055815:Young Adult