title: Digital image analysis of ossification centers in the axial dens and body in the human fetus.
abstract: OBJECTIVE
  The detailed understanding of the anatomy and timing of ossification centers is indispensable in both determining the fetal stage and maturity and for detecting congenital disorders. This study was performed to quantitatively examine the odontoid and body ossification centers in the axis with respect to their linear, planar and volumetric parameters.
  
  
  METHODS
  Using the methods of CT, digital image analysis and statistics, the size of the odontoid and body ossification centers in the axis in 55 spontaneously aborted human fetuses aged 17-30 weeks was studied.
  
  
  RESULTS
  With no sex difference, the best fit growth dynamics for odontoid and body ossification centers of the axis were, respectively, as follows: for transverse diameter y = -10.752 + 4.276 × ln(age) ± 0.335 and y = -10.578 + 4.265 × ln(age) ± 0.338, for sagittal diameter y = -4.329 + 2.010 × ln(age) ± 0.182 and y = -3.934 + 1.930 × ln(age) ± 0.182, for cross-sectional area y = -7.102 + 0.520 × age ± 0.724 and y = -7.002 + 0.521 × age ± 0.726, and for volume y = -37.021 + 14.014 × ln(age) ± 1.091 and y = -37.425 + 14.197 × ln(age) ± 1.109.
  
  
  CONCLUSIONS
  With no sex differences, the odontoid and body ossification centers of the axis grow logarithmically in transverse and sagittal diameters, and in volume, while proportionately in cross-sectional area. Our specific-age reference data for the odontoid and body ossification centers of the axis may be relevant for determining the fetal stage and maturity and for in utero three-dimensional sonographic detecting segmentation anomalies of the axis.
authors.affiliation: Department of Normal Anatomy, The Ludwik Rydygier Collegium Medicum in Bydgoszcz, The Nicolaus Copernicus University in Toruń, Łukasiewicza 1 Street, 85-821, Bydgoszcz, Poland.
authors.forename: Mariusz
authors.initials: M
authors.lastname: Baumgart
authors.affiliation: Department of Normal Anatomy, The Ludwik Rydygier Collegium Medicum in Bydgoszcz, The Nicolaus Copernicus University in Toruń, Łukasiewicza 1 Street, 85-821, Bydgoszcz, Poland.
authors.forename: Marcin
authors.initials: M
authors.lastname: Wiśniewski
authors.affiliation: Department of Normal Anatomy, The Ludwik Rydygier Collegium Medicum in Bydgoszcz, The Nicolaus Copernicus University in Toruń, Łukasiewicza 1 Street, 85-821, Bydgoszcz, Poland.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Grzonkowska
authors.affiliation: Department of Positron Emission Tomography and Molecular Imaging, The Ludwik Rydygier Collegium Medicum in Bydgoszcz, The Nicolaus Copernicus University in Toruń, Łukasiewicza 1 Street, 85-821, Bydgoszcz, Poland.
authors.forename: Bogdan
authors.initials: B
authors.lastname: Małkowski
authors.affiliation: Department of Normal Anatomy, The Ludwik Rydygier Collegium Medicum in Bydgoszcz, The Nicolaus Copernicus University in Toruń, Łukasiewicza 1 Street, 85-821, Bydgoszcz, Poland.
authors.forename: Mateusz
authors.initials: M
authors.lastname: Badura
authors.affiliation: Department of Normal Anatomy, The Ludwik Rydygier Collegium Medicum in Bydgoszcz, The Nicolaus Copernicus University in Toruń, Łukasiewicza 1 Street, 85-821, Bydgoszcz, Poland.
authors.forename: Maria
authors.initials: M
authors.lastname: Dąbrowska
authors.affiliation: Department of Normal Anatomy, The Ludwik Rydygier Collegium Medicum in Bydgoszcz, The Nicolaus Copernicus University in Toruń, Łukasiewicza 1 Street, 85-821, Bydgoszcz, Poland. kizanat@cm.umk.pl.
authors.forename: Michał
authors.initials: M
authors.lastname: Szpinda
mesh_terms: D037881:Aborted Fetus; D000367:Age Factors; D005260:Female; D047109:Fetal Development; D005865:Gestational Age; D006801:Humans; D008297:Male; D008962:Models, Theoretical; D009139:Musculoskeletal Abnormalities / Q000000981:diagnostic imaging; D009809:Odontoid Process / Q000000981:diagnostic imaging* / Q000196:embryology*; D010012:Osteogenesis; D011247:Pregnancy; D012727:Sex Characteristics; D014057:Tomography, X-Ray Computed
keywords: Axis vertebra; Growth dynamics; Human fetus; Odontoid process; Ossification center; Size