title: Fetal development of the auditory tube and paratubal musculature.
abstract: The purpose of this study was to describe the prenatal development of the human auditory tube and paratubal musculature. Twenty prenatal specimens, 8 to 36 weeks of age postconception were embedded in celloidin, sectioned, and stained with hemotoxylin eosin. Qualitative data on the initial appearance and development were obtained using light microscopy (Plates I-VI). Linear and angular measurements were obtained from traced sections. The analysis showed the following: morphological differentiation of this area occurs between 8 and 16 weeks menstrual age; tubal structures develop in anterior-posterior and medial-lateral gradients; the tubal lumen of the perinatal fetus is cylindrical and lacks an isthmus; the allometric growth of the cartilaginous portion of the lumen between 16 and 28 weeks is responsible for the greatest increase in the tubal length during the fetal period.
authors.forename: J D
authors.initials: JD
authors.lastname: Swarts
authors.forename: S R
authors.initials: SR
authors.lastname: Rood
authors.forename: W J
authors.initials: WJ
authors.lastname: Doyle
mesh_terms: D002356:Cartilage / Q000196:embryology; D005314:Embryonic and Fetal Development; D005064:Eustachian Tube / Q000196:embryology*; D005152:Facial Muscles / Q000196:embryology*; D006801:Humans; D013997:Time Factors