title: Morphogenesis of the human laryngeal ventricles.
abstract: BACKGROUND
  Two theories explain the origin of human laryngeal ventricles: (1) ventricles derive from the fifth pharyngeal pouches; (2) development independent from the pouches.
  
  
  METHODS
  In all, there were 21 serially sectioned human embryos from stages 15 to 23, and 11 fetuses of 9 to 18 weeks. Computer-aided 3-dimentional reconstructions were made.
  
  
  RESULTS
  The cranial part of the laryngeal sulcus and future vestibule expands from the pharyngeal floor between the third and fourth pharyngeal pouches during stages 15 and 16 (33-37 days). The primordia of the ventricles appeared at stage 18 (44 days) as 2 lateral swellings in the caudal end of the future vestibule, limited by the third pharyngeal pouches. Active epithelial expansion and subsequent canalization during late embryonic and early fetal periods finalizes their development.
  
  
  CONCLUSIONS
  The laryngeal ventricles do not derive from the pharyngeal pouches but the median region of the pharyngeal floor between the third and fourth pharyngeal pouches and arches at the caudal end of the future vestibule.
authors.affiliation: Departamento de Anatomía y Embriología Humana I, Facultad de Medicina, Universidad Complutense de Madrid, Spain.
authors.forename: Fermín
authors.initials: F
authors.lastname: Viejo
authors.forename: Arán
authors.initials: A
authors.lastname: Pascual-Font
authors.forename: Luis
authors.initials: L
authors.lastname: Rivas
authors.forename: Ignacio
authors.initials: I
authors.lastname: Hernández-Morato
authors.forename: Teresa
authors.initials: T
authors.lastname: Vázquez
authors.forename: Marc
authors.initials: M
authors.lastname: Rodriguez-Niedenführ
authors.forename: Stephen
authors.initials: S
authors.lastname: McHanwell
authors.forename: José R
authors.initials: JR
authors.lastname: Sanudo
mesh_terms: D005333:Fetus; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D007830:Larynx / Q000196:embryology*; D009024:Morphogenesis; D010614:Pharynx / Q000196:embryology*