title: Skull base morphology in fibroblast growth factor receptor type 2-related faciocraniosynostosis: a descriptive analysis.
abstract: BACKGROUND
  Children with faciocraniosynostosis present skull base abnormalities and may develop hydrocephalus or cerebellar tonsils ectopia (CTE). Several pathophysiological hypotheses were formulated in the past decades to explain these associations. However, no study has described in a genetically homogeneous population with confirmed fibroblast growth factor receptor type 2 (FGFR2) mutation eventual correlations between skull base abnormalities and hydrocephalus or CTE.
  
  
  OBJECTIVE
  To illustrate these features in children <2 years of age with a genetically confirmed FGFR2-related faciocraniosynostosis.
  
  
  METHODS
  We measured the foramen magnum area (FMA) and its sagittal and transversal components: the right, left, and mean area of the jugular foramen; the posterior fossa volume; and the cerebellar volume on preoperative millimetric computed tomography scan slices in 31 children with an FGFR2 mutation (14 with Crouzon syndrome, 11 with Apert syndrome, and 6 with Pfeiffer syndrome). They were compared with 17 children without synostosis. All children were <24 months of age. We correlated all these measures with the presence of hydrocephalus or CTE.
  
  
  RESULTS
  We observed a significantly small FMA in children with Crouzon (P = .03) and in children with Pfeiffer (P = .05) resulting from a reduced sagittal diameter (P = .02 for Crouzon and P = .002 for Pfeiffer). Hydrocephalus was associated with small FMA (P = .02). The jugular foramen area, posterior fossa volume, and cerebellar volume were not associated with hydrocephalus or CTE. Hydrocephalus and CTE were statistically associated (P = .002).
  
  
  CONCLUSIONS
  Hydrocephalus in FGFR2-related Crouzon and Pfeiffer syndromes is statistically associated with a small FMA. Hydrocephalus is statistically associated with CTE.
authors.affiliation: *Unité de Chirurgie Craniofaciale, Service de Neurochirurgie Pédiatrique, Centre de Référence National des Dysostoses Crâniofaciales, Hôpital Necker-Enfants Malades, APHP, Paris, France; ‡Service de Neurochirurgie, Hôpital Gabriel Montpied, Clermont-Ferrand, France; §Laboratoire d'anatomie, UFR Médecine, Universite[Combining Acute Accent] d'Auvergne, Clermont-Ferrand, France; ¶Image-Guided Clinical Neuroscience and Connectomics, EA 7282, UFR Médecine, Université Clermont 1, Universite d'Auvergne, Clermont-Ferrand, France; ‖Service de Biochimie et Biologie Moléculaire, Hôpital Lariboisière, APHP, Paris, France; #Département de Radiologie, Hôpital Necker-Enfants Malades, APHP, Paris, France.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Coll
authors.forename: Eric
authors.initials: E
authors.lastname: Arnaud
authors.forename: Corinne
authors.initials: C
authors.lastname: Collet
authors.forename: Francis
authors.initials: F
authors.lastname: Brunelle
authors.forename: Christian
authors.initials: C
authors.lastname: Sainte-Rose
authors.forename: Federico
authors.initials: F
authors.lastname: Di Rocco
mesh_terms: D002675:Child, Preschool; D019465:Craniofacial Abnormalities / Q000150:complications / Q000235:genetics / Q000473:pathology; D003398:Craniosynostoses / Q000150:complications / Q000235:genetics / Q000473:pathology*; D005260:Female; D005539:Foramen Magnum / Q000002:abnormalities / Q000000981:diagnostic imaging; D006801:Humans; D006849:Hydrocephalus / Q000209:etiology; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009154:Mutation; D051497:Receptor, Fibroblast Growth Factor, Type 2 / Q000235:genetics*; D019291:Skull Base / Q000002:abnormalities* / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed
chemical_list: D051497:Receptor, Fibroblast Growth Factor, Type 2