Explore chapters and articles related to this topic
Disorders of Hearing
Published in Anthony N. Nicholson, The Neurosciences and the Practice of Aviation Medicine, 2017
Linda M. Luxon, Ronald Hinchcliffe
The internal ear is embedded in the bony labyrinth filled with perilymph, and can be divided into three anatomical and functional regions: the semicircular canals, the vestibule and the cochlea. Within the bony labyrinth lies the membranous labyrinth which is filled with endolymph and contains the sensory cells of both hearing and balance. The bony cochlea resembles the shell of a snail, within which lies the cochlear duct with a flat floor known as the spiral lamina, a side wall which is comprised mainly of the stria vascularis and a sloping diagonal ‘roof’ known as the vestibular membrane of Reissner (1824–1878) (Figure 19.2). The spiral organ of Corti (1822–1876) is situated on the basilar membrane and contains the auditory sensory receptor cells known as hair cells. There are two types of cells, the inner and the outer hair cells, both of which have stereocilia projecting from their upper endolymphatic surface. The stereocilia are embedded in the gelatinous tectorial membrane.
Risk factors for falls in Iranian older adults: a case-control study
Published in International Journal of Injury Control and Safety Promotion, 2019
Zahra Taheri-Kharameh, Jalal Poorolajal, Saeed Bashirian, Rashid Heydari Moghadam, Mahmoud Parham, Majid Barati, Éva Rásky
In this study, the greater hearing loss was significantly associated with self-reported falls. Contributing to the literature, our results assess the association between hearing loss and fallings. Several mechanisms could be used to explain the association between hearing loss and fallings. There may be a concomitant dysfunction of both the cochlear and vestibular structures regarding their shared location within the bony labyrinth of the inner ear. Finally, the association of hearing loss with fallings may be mediated through reduced cognitive resources (Jiam et al., 2016; Kamil et al., 2016).
Semi-automatic 3D reconstruction of middle and inner ear structures using CBCT
Published in Computer Methods in Biomechanics and Biomedical Engineering: Imaging & Visualization, 2023
Florian Beguet, Thierry Cresson, Mathieu Schmittbuhl, Cédric Doucet, David Camirand, Philippe Harris, Jean-Luc Mari, Jacques de Guise
In the third group, prior statistical knowledge is used to solve the various problems associated with the methods mentioned above. Shape, displacements, deformations, and intensities can be used to produce an anatomical database to constrain the system to generate a representative segmentation of the structure. Some authors proposed imposing a global shape control based on an active shape model (Cootes and Taylor 1992) algorithm to segment the structures of the inner and middle ear (Noble et al. 2011; Cerrolaza et al. 2014; Ruiz Pujadas et al. 2016; Zhu et al. 2017). Usually, the shape model are based on models built on segmented cadaver human ears recorded with a μCT (Noble et al. 2011; Poznyakovskiy et al. 2013). The methods of Ruiz Pujadas et al. (2016) and Zhu et al. (2017) are used to segment the inner ear on micro-CT and MRI images, respectively, and provide an accuracy of 95% with the Dice Similarity Coefficient (DSC). The algorithm Noble et al. (2011) used to segment the inner ear with CT volumes is less accurate than others (75% with the DSC) but has the advantage of providing a complete segmentation of the bony labyrinth with differentiation between the scales (cochlea chambers), even though this differentiation is often not visible in CT-scan images. Cerrolaza et al. (2014) proposed the use of a multi-resolution hierarchical point distribution model to segment the middle ear and inner ear. Despite low accuracy (approximately 80% with DSC depending on the structure), this method highlights the interest of considering the neighbouring structures in the segmentation of these structures. In addition, the use of multi-resolution approaches reduces the influence of a limited training database, which often limits statistical methods. This can be seen with the structures of the middle and inner ear due to the great variability of deformities caused by diseases and the difficulty of obtaining a very high-resolution database of cadaveric ears.
A comprehensive finite element model for studying Cochlear-Vestibular interaction
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2022
Junfeng Liang, Zhang Ke, Paige V. Welch, Rong Z. Gan, Chenkai Dai
In vertebrates, the inner ear consists of two main functional parts: the cochlea, dedicated to hearing and the vestibular system, dedicated to balance. These two organs are connected by lymphatic fluids, which fill the two bony labyrinth sections separated by the membranous labyrinth, namely perilymph and endolymph.