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Pendred’s Syndrome: Association of Congenital Deafness with Sporadic Goiter
Published in Geraldo Medeiros-Neto, John Bruton Stanbury, Inherited Disorders of the Thyroid System, 2019
Geraldo Medeiros-Neto, John Bruton Stanbury
The first detailed histological study describing the cochlea in Pendred’s syndrome was in 1968.36 That study reported the findings in a 60-year-old male who had been born deaf and developed a large goiter (275 g at surgery). The perchlorate discharge test showed a 28% fall of the trapped iodide in 1 hour. The patient died of coronary occlusion and the temporal bones were fixed in formalin for further studies of the middle and inner ear. Gross inspection showed no abnormalities. The middle ear was normal. The labyrinthine capsule showed no signs of otosclerosis. Malformation was present in the osseous cavities with the cochlea being accommodated in a single cavity with only just a trace of two turns. The vestibule and semicircular canal system had cavities that were larger and coarser than normal. Only two cochlear turns enveloped a defective modiolus with little bone. Pronounced dilatation of Reissner’s membrane was also found. In the organ of Corti there was no trace of outer or inner hair cells and total atrophy of the tectoral membrane. The lamina spiralis contained no nerve fibers. Only a few scattered ganglion cells were in the spiral canal and very few acoustic branches in the 8th nerve. The histological appearance corresponded rather accurately to previously described Mondini’s type of developmental anomaly of the cochlea.
Acute vertigo
Published in S. Musheer Hussain, Paul White, Kim W Ah-See, Patrick Spielmann, Mary-Louise Montague, ENT Head & Neck Emergencies, 2018
Rahul Kanegaonkar, Max Whittaker
Ménière’s disease is a relatively uncommon cause of vertigo, with an estimated incidence of 5 per 100,000 per year. Patients experience spontaneous, unpredictable bouts of severe rotatory vertigo. Episodes are often preceded by aural fullness in the affected ear and classically associated with hearing loss and roaring tinnitus. Although the exact aetiology is uncertain, post-mortem studies have demonstrated expansion of the scala media compartment of the inner ear. Symptoms are thought to arise owing to either rupture of Reissner’s membrane and toxic overstimulation of the neuroepithelial elements of the inner ear, or an abnormality of longitudinal drainage of endolymph to the endolymphatic sac. Once a critical level is reached, endolymph drains into the utricle, stretching the cristae of the semicircular canals and resulting in profound vertigo.
Anatomy of the Cochlea and Vestibular System: Relating Ultrastructure to Function
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
Reissner’s membrane is a thin epithelial sheet formed of two cell layers (Figure 47.2b).148–150 A continuous layer of epithelial cells lines the scala media side and, since their apical surfaces face endolymph, they have tight junctions sealing the spaces between adjacent cells. The basal side of the epithelium, in the scala vestibuli, is covered with mesenchymal cells that are bathed in perilymph. The primary role of Reissner’s membrane, to maintain the electrical and chemical separation of endolymph and perilymph, is achieved at the level of the tight junctions between the epithelial cells. There is also some evidence that the epithelial cells may have a phagocytic function taking up and then breaking down cell debris released into the endolymphatic compartment. Reissner’s membrane also appears to have some elasticity as it can accommodate by swelling outwards into the scala vestibuli quite large increases in endolymph volume – endolymphatic hydrops – such as occurs with ion imbalance that results in water influx into the scala media, before it ruptures (as in Ménière’s syndrome).151,152 How this is achieved, and whether Reissner’s membrane has additional roles, remains to be determined.
Correlation between grading methods of the cochlear endolymphatic hydrops and hearing loss in meniere’s disease using three-dimensional real inversion recovery sequences
Published in Acta Oto-Laryngologica, 2023
Zhihao Han, Xiaoyu Qiu, Yan Huang, Qian Sun, Heyu Ding, Jing Xie, Jingying Guo, Yutong Yang, Yuhe Liu, Shusheng Gong, Pengfei Zhao, Zhenchang Wang
Nakashima et al. [8] evaluated whether Reissner’s membrane is displaced, as well as the area of the cochlear duct and the area of the scala vestibuli. Gürkov et al. [9] (similar to Yang et al. [6]) focused on the appearance of the scala tympani and vestibuli surrounding the dark scala media. Baráth et al. [10] (similar to Bernaerts et al. [11]) examined the degree of dilatation of the endolymphatic space and the presence or absence of the perilymphatic space. In He et al. [12], the evaluation criterion was the degree of scala media expansion and the morphology of the scala media. In this study, we adopted 3D-real IR sequences and referred to the grading methods of cochlear EH proposed by Nakashima et al. (M1) [8], Gürkov et al. (M2) [9] (similar to Yang et al. [6]), Baráth et al. (M3) [10] (similar to Bernaerts et al. [11]), and He et al. (M4) [12] to investigate the consistency of different methods for determining MD cochlear EH. Furthermore, this study explored the correlation between the grade of different methods and the degree of hearing loss to find the most applicable method for relevant clinical diagnostic and therapeutic studies.
Magnetic resonance imaging of the endolymphatic space in patients with benign paroxysmal positional vertigo: volume ratio and distribution rate of the endolymphatic space
Published in Acta Oto-Laryngologica, 2022
Hiroshi Inui, Tsuyoshi Sakamoto, Taeko Ito, Tadashi Kitahara
In 1938, Hallpike and Cairns [12] reported that endolymphatic fluid is produced in the cochlea and absorbed in the endolymphatic duct by longitudinal flow. Schuknecht frequently observed ruptures of Reissner’s membrane, and the rupture and potassium intoxication theory has been the predominant theory of Meniere’s vertigo attacks since the 1960s [13]. On the contrary, Brown et al. [14] rejected this theory and considered the alternative theory of raised endolymphatic pressure. Some researchers have described that the relationship between BPPV and the ELH. They observed otoconial debris floats freely within the endolymphatic fluid in patients with BPPV and they concluded that endolymphatic debris may cause either or both positional vertigo and hydrops [6,15]. In the present study, we reported significant differences in the TFS volume of the cochlea, vestibule, and SCCs and in the ELS volume of the SCCs between the CS and BPPV groups. We previously found age-related difference in the TFS volume in the inner ear, sex-related difference in the TFS volume in the cochlea, and left-right-related difference in the TFS volume in the vestibule in healthy controls [16]. Therefore, we analysed the ELS/TFS volume ratios (%). The differences in the ELS/TFS volume ratio between the BPPV and CS groups were not significant. Extended ELS did not exist in patients with BPPV.
Relationship between changes in hearing function and volumes of endolymphatic hydrops after endolymphatic sac drainage
Published in Acta Oto-Laryngologica, 2019
Taeko Ito, Hiroshi Inui, Toshiteru Miyasaka, Tomoyuki Shiozaki, Hiroto Fujita, Toshiaki Yamanaka, Kimihiko Kichikawa, Tadashi Kitahara
For evaluation of EH, the area of total fluid space in the cochlea and vestibule was measured on the SPACE sequence image and the area of ELS in the cochlea and vestibule was also measured on ‘PPI–PEI’ images using our workstation. Then, the area ratio of ELS to total fluid space was calculated. The degrees of cochlear and vestibular EH were classified as none, mild, or significant, according to the criteria reported by Nakashima et al. [19]. Patients classified as having no EH in the cochlea showed no displacement of Reissner’s membrane. Those with mild cochlear EH showed displacement of Reissner’s membrane, but the area of the ELS did not exceed the area of the scala vestibuli. In patients with significant cochlear EH, the area of the ELS exceeded the area of the scala vestibuli. When the grade of the EH differed between the basal and upper turns of the cochlea, the higher grade was adopted. In the vestibule, the grading was determined from the ratio of the area of ELS to that of the vestibular fluid space. Patients with no EH in the vestibule had a ratio of ≤1:3, those with mild EH had ratios of 1:3–1:2, and those with significant EH had a ratio >1:2. In the present study, both mild and significant EH were defined as ‘positive.’