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Citation
Tags
HERO ID
1975828
Reference Type
Journal Article
Title
New insight into the bony labyrinth: a microcomputed tomography study
Author(s)
Richard, C; Laroche, N; Malaval, L; Dumollard, JM; Martin, Ch; Peoch, M; Vico, L; Prades, JM
Year
2010
Is Peer Reviewed?
0
Journal
Auris Nasus Larynx
ISSN:
0385-8146
Volume
37
Issue
2
Page Numbers
155-161
Language
English
PMID
19577870
DOI
10.1016/j.anl.2009.04.014
Abstract
OBJECTIVES:
To visualize and quantify the morphology and mineralization of the developing fetal human bony labyrinth, using 3D-microcomputed tomography (3D-microCT) imaging.
METHODS:
Eleven right temporal bones from late second and third trimester fetuses were used in this prospective pilot study. After fixation in 10% formalin solution, all samples underwent a microcomputed tomography (microCT) scan, permitting the 3D imaging of the bony labyrinth as well as the quantitative assessment of mineral density, angular distances and dimensions of inner ear components the progression of ossification was precised with histological observations.
RESULTS:
Our findings show different rates of growth among the semicircular canals, the vestibular aqueduct, the oval window, the round window and the cochlea. The final sizes of the cochlea and round window are achieved at 23 weeks of gestation, with heights of 5mm and 2mm, respectively. The oval window reaches adult size at 35 weeks, whereas the vestibular aqueduct will attain adult size after birth. An increasing degree of torsion of each semicircular canal is observed during fetal development. The superior semicircular canal achieves adult size at 24 weeks, before the posterior and the lateral canals (25 weeks). The time-course of ossification and mineralization observed in structures and confirmed by histology.
CONCLUSIONS:
During this developmental period poorly studied until now, our findings suggest that each part of the bony labyrinth follows distinct growth and ossification kinetics trajectories, some of these reaching their adult size only after birth.
Keywords
Calcification, Physiologic/physiology; Cochlea/embryology/radiography; Ear, Inner/ embryology/ radiography; Gestational Age; Image Processing, Computer-Assisted; Imaging, Three-Dimensional; Infant, Newborn; Organ Size; Osteogenesis/physiology; Oval Window, Ear/embryology/radiography; Pregnancy; Reference Values; Round Window, Ear/embryology/radiography; Semicircular Canals/embryology/radiography; Vestibular Aqueduct/embryology/radiography; X-Ray Microtomography
Tags
IRIS
•
Formaldehyde
Reproductive and Developmental Effects
Screened
Title/abstract
Methodology/therapeutics
Retroactive RIS import
2015
FA DevRepro 072115
Methodology/Therapeutics-Population Criteria
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