Fetal Development Of The Carotid Canal With Special Reference To A Contribution Of The Sphenoid Bone And Pharyngotympanic Tube

Yohei Honkura, Masahito Yamamoto, José Francisco Rodríguez-Vázquez, Gen Murakam, Hiroshi Abe, Shin Ichi Abe, Yukio Katori

Research output: Contribution to journalArticlepeer-review

4 Citations (Scopus)


The bony carotid canal is a tube-like bone with a rough surface in contrast to smooth surfaces of the other parts of the temporal bone petrosal portion (petrosa): it takes an impression of the additional, out-sourcing product. No study had been conducted to evaluate a contribution of the adjacent sphenoid and pharyngotympanic tube (PTT) to the carotid canal. We examined sagittal and horizontal histological sections of hemi-heads from 37 human fetuses at 10 to 37 weeks. At 10 to 18 weeks, the future carotid canal was identified as a wide loose space between the cartilaginous cochlea and the ossified or cartilaginous sphenoid elements (ala temporalis and pterygoid). A linear mesenchymal condensation extending between the cochlear wall and ala temporalis suggested the future antero-inferior margin of the carotid canal. This delineation was more clearly identified in later stages. After 25 weeks, 1) the growing pterygoid pushed the PTT upward and, in turn, the PTT pushed the internal carotid artery (ICA) upward toward the petrosa: 2) a membranous ossification occurs in the dense mesenchymal tissue, the latter of which took an appearance of an anterior process of the petrosa; 3) the bony process of the petrosa involved the ICA inside or posteriorly. The bony carotid canal was made with membranous ossification in the dense mesenchymal tissue between the petrosa and sphenoid. The mother tissue was detached from the sphenoid by the PTT. The ossification of the septum between the ICA and tympanic cavity seemed to continue after birth.

Original languageEnglish
Pages (from-to)259-269
Number of pages11
JournalAnatomy and Cell Biology
Issue number2
Publication statusPublished - 2021 Jun
Externally publishedYes


  • Ala temporalis
  • Carotid canal
  • Membranous ossification
  • Pterygoid
  • Sphenoid bone

ASJC Scopus subject areas

  • Anatomy
  • Histology
  • Developmental Biology
  • Cellular and Molecular Neuroscience
  • Cell Biology


Dive into the research topics of 'Fetal Development Of The Carotid Canal With Special Reference To A Contribution Of The Sphenoid Bone And Pharyngotympanic Tube'. Together they form a unique fingerprint.

Cite this