title: 3D displacement of the middle ear ossicles in the quasi-static pressure regime using new X-ray stereoscopy technique.
abstract: A novel X-ray stereoscopy technique, using greyscale information obtained from moving markers, was used to study the 3D motion in both gerbil and rabbit middle ear ossicles in the quasi-static pressure regime. The motion can be measured without visually exposing the ossicles. The ossicles showed non-linear behaviour as a function of both pressure and frequency. For instance, about 80% of the maximum umbo displacement occurs at a 1 kPa (peak-to-peak) pressure load, while a limited increase of the amplitude is noticed when the pressure goes to 2 kPa. In rabbit the ratio of stapes to umbo motion amplitude was 0.35 for a pressure of 2 kPa (peak-to-peak) at 0.5 Hz. From two stereoscopic projections of the marker paths, 3D motion of the ossicles could be calculated. This motion is demonstrated on high-resolution computer models in order to visualize ossicular chain behaviour.
authors.affiliation: Department of Biomedical Physics, Alneelain University, Algamhouria Avenue, Khartoum, Sudan; Laboratory of Biomedical Physics, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium. Electronic address: wasil.hashim@uantwerpen.be.
authors.forename: Wasil H M
authors.initials: WHM
authors.lastname: Salih
authors.affiliation: Laboratory of Biomedical Physics, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium. Electronic address: joris.soons@uantwerpen.be.
authors.forename: Joris A M
authors.initials: JAM
authors.lastname: Soons
authors.affiliation: Laboratory of Biomedical Physics, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium. Electronic address: joris.dirckx@uantwerpen.be.
authors.forename: Joris J J
authors.initials: JJJ
authors.lastname: Dirckx
mesh_terms: D000161:Acoustic Stimulation; D000818:Animals; D003051:Cochlea / Q000502:physiology; D003198:Computer Simulation; D004429:Ear Ossicles / Q000502:physiology*; D005849:Gerbillinae; D021621:Imaging, Three-Dimensional; D007188:Incus / Q000502:physiology; D007368:Interferometry; D009038:Motion; D009998:Ossicular Prosthesis; D011312:Pressure; D011817:Rabbits; D013199:Stapes / Q000502:physiology; D014965:X-Rays
keywords: Ossicular chain motion; Transfer function; X-ray stereoscopy