Original Research ARTICLE
ANALYSIS OF VESTIBULAR LABYRINTHINE GEOMETRY AND VARIATION IN THE HUMAN TEMPORAL BONE
- 1Department of Otolaryngology, Innsbruck Medical University, Austria
- 2Department of Biotechnology & Food Engineering, MCI Management Center Innsbruck, Austria
- 3VetImaging, VetCore Facility for Research, University of Veterinary Medicine, Austria
- 4Institute of Bomedical Image Analysis, UMIT - Private Universität für Gesundheitswissenschaften, Medizinische Informatik und Technik, Austria
- 5MED-EL GmbH, Austria
- 6Institute of Electrical and Biomedical Engineering, UMIT - Private Universität für Gesundheitswissenschaften, Medizinische Informatik und Technik, Austria
- 7Institute of Biomedical Engineering and Informatics, Technische Universität Ilmenau, Germany
- 8Department of Anatomy, Histology and Embryology, Division of Clinical and Functional Anatomy, Innsbruck Medical University, Austria
- 9Division of Clinical and Functional Anatomy, Innsbruck Medical University, Austria
Stable posture and body movement in humans is dictated by the precise functioning of the ampulla organs in the semi-circular canals. Statistical analysis of the interrelationship between bony and membranous compartments within the semi-circular canals is dependent on the visualization of soft tissue structures. 31 human inner ears were prepared, post-fixed with osmium tetroxide and decalcified for soft tissue contrast enhancement. High resolution X-ray microtomography images at 15 µm voxel-size were manually segmented. This data served as templates for centerline generation and cross-sectional area extraction. Our estimates demonstrate the variability of individual specimens from averaged centerlines of both bony and membranous labyrinth. Centerline lengths and cross-sectional areas along these lines were identified from segmented data. Using centerlines weighted by the inverse squares of the cross-sectional areas, plane angles could be quantified. The fit planes indicate that the bony labyrinth resembles a Cartesian coordinate system more closely than the membranous labyrinth. A widening in the membranous labyrinth of the lateral semi-circular canal was observed in some of the specimens. Likewise, the cross-sectional areas in the perilymphatic spaces of the lateral canal differed from the other canals. For the first time we could precisely describe the geometry of the human membranous labyrinth based on a large sample size. Awareness of the variations in the canal geometry of the membranous and bony labyrinth would be a helpful reference in designing electrodes for future vestibular prosthesis and simulating fluid dynamics more precisely.
Keywords: membranous labyrinth, Semi-circular canals, Vestibular labyrinth, microCT, Centerlines, Cross-sectional area, Inner ear, Humans
Received: 10 Jul 2017;
Accepted: 12 Feb 2018.
Edited by:Pascal Senn, Geneva University Hospitals (HUG), Switzerland
Reviewed by:Sébastien SCHMERBER, Université Grenoble Alpes, France
Georgios Mantokoudis, University Hospital Bern, Switzerland
Copyright: © 2018 Johnson Chacko, Schmidbauer, Handschuh, Reka, Fritscher, Raudaschl, Saba, Handler, Schier, Baumgarten, Fischer, Pechriggl, Hoermann, Brenner, Glueckert and Schrott-Fischer. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Dr. Rudolf Glueckert, Innsbruck Medical University, Department of Otolaryngology, Innsbruck, Austria, Rudolf.Glueckert@i-med.ac.at