China
Africa
Explore chapters and articles related to this topic
Otosclerosis
Published in John C Watkinson, Raymond W Clarke, Christopher P Aldren, Doris-Eva Bamiou, Raymond W Clarke, Richard M Irving, Haytham Kubba, Shakeel R Saeed, Paediatrics, The Ear, Skull Base, 2018
Christopher P. Aldren, Thanos Bibas, Arnold J.N. Bittermann, George G. Browning, Wilko Grolman, Peter A. Rea, Rinze A. Tange, Inge Wegner
Sodium fluoride is a known inhibitor of osteoclast activity and so a stabilizer of bone turnover. It also leads to increased calcium deposition in otospongiotic foci and decreased bone remodelling.121 This property makes it a potential treatment for otosclerosis and its use was first reported in 1964.122 The release of cytokines from bony remodelling adjacent to the cochlear spiral ligament may be responsible for the sensorineural hearing loss sometimes seen in otosclerosis. Sodium fluoride has the potential to reduce this.
Anatomy
Published in Stanley A. Gelfand, Hearing, 2017
The structures and orientation of the scala media are shown schematically in Figure 2.18. The scala media is attached medially to the osseous spiral lamina, just described, and laterally to the outer wall of the cochlea by a fibrous connective tissue called the spiral ligament. Looking first at the osseous spiral lamina (toward the left in the figure), we see that this bony shelf is actually composed of two plates, separated by a space through which pass fibers of the auditory nerve. These fibers enter via openings called the habenula perforata. Resting on the osseous spiral lamina is a thickened band of periosteum, the limbus. Reissner's membrane extends from the top of the inner aspect of the limbus to the outer wall of the canal. The side of the limbus facing the organ of Corti is concave outward. The tectorial membrane is attached to the limbus at the upper lip of this concave part, forming a space called the internal spiral sulcus. The basilar membrane extends from the lower lip of the limbus to the spiral ligament at the outer wall of the duct. The spiral ligament itself has been described in considerable detail (Takahashi and Kimura, 1970; Morera et al., 1980; Henson et al., 1984); it is involved in the metabolic activities of the inner ear in addition to its role as a crucial supporting structure.
Effects of basilar-membrane lesions on dynamic responses of the middle ear
Published in Acta Oto-Laryngologica, 2023
Junyi Liang, Wen Xie, Wenjuan Yao, Maoli Duan
Some disorders of metabolism in the cochlear such as mucopolysaccharidosis can cause basilar membrane damage or an increase the sensory cell weight. In addition, the mass of the spiral limbus cells, spiral process, and the spiral ligament increases notably [16]. All these structures are within the organ of Corti, which attaches to the basilar membrane. As a result, added mass of the basilar membrane increases. In addition, some genetic defects can lead to congenital deafness. The main characteristics embody in the hypertrophy of Sertoli cells in cortis device, leads to the increase of the basilar membrane mass. Added mass in the basilar membrane was adopted as the following situation: average thickness increased 0.15 mm, while the added mass is 36 × 10−9 kg. Under 90 dB SPL, compared with the normal human ear, the frequency-response curve of displacement and velocity were respectively obtained, as shown in Figure 7.
An update on current and potential genetic insights and diagnosis of Alport syndrome
Published in Expert Opinion on Orphan Drugs, 2020
Several possible mechanisms for Alport-associated hearing loss have been proposed. Studies in mice suggest that the up-regulation of endothelin-1 induces extracellular matrix genes leading to strial capillary basement membrane thickening and metabolic and oxidative stress that could be prevented by blockade of endothelin A receptors [67]. Harvey and colleagues proposed that the absence of the collagen IV alpha345 network limits the capacity of the spiral ligament to impart tension on the basilar membrane, reducing the perception of high-frequency sounds [62]. A third hypothesis is that the abnormal basement membrane under the organ of Corti results in defective adhesion of the organ of Corti to the basilar membrane, preventing normal hair cell responses to the motion of the basilar membrane [60].
Expression of Na/K-ATPase subunits in the human cochlea: a confocal and super-resolution microscopy study with special reference to auditory nerve excitation and cochlear implantation
Published in Upsala Journal of Medical Sciences, 2019
Wei Liu, Maria Luque, Rudolf Glueckert, Niklas Danckwardt-Lillieström, Charlotta Kämpfe Nordström, Anneliese Schrott-Fischer, Helge Rask-Andersen
Animal data show a modulation of Na/K-ATPase isoforms during inner ear maturation that may be related to changes in ion concentration and formation of the endo-cochlear potential (29,33). The ubiquitous α1β1 subunit combination is expressed in the basolateral membrane of the marginal cells of the stria vascularis. However, studies performed in different species suggest that stria vascularis mostly expresses β2 (1,34) or both β1 and β2 (35), while β1 is expressed in the spiral ligament. These findings were somewhat contradicted by Liu et al. (2) who found only the α1β1 subunits in the human stria. The different results may be explained by the species used and the techniques used to detect the enzyme pump. False color display shows a remarkable diversity in Na/K-ATPase intensity in various domains. Reissner’s membrane (36), basal cells and intermediate cells of the stria vascularis, types I and III spiral ligament fibrocytes, inner pillar cells, outer pillar cells, and Deiters cells lacked visible Na/K-ATPase β1 expression. Reissner’s membrane separates large ion concentrations between the endo- and perilymph. It suggests that alternate instruments exist to avoid ionic equilibration, though some α1 activity could be recognized. The high intensity of Na/K-ATPase at the spiral prominence and type II fibrocytes was striking. It is in accordance with theories of active trans-epithelial water flux and K+ recirculation in the lateral wall (2,37,38).