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  1. Autoimmune Inner Ear Disease

    Science.gov (United States)

    ... Find an ENT Doctor Near You Autoimmune Inner Ear Disease Autoimmune Inner Ear Disease Patient Health Information ... with a hearing loss. How Does the Healthy Ear Work? The ear has three main parts: the ...

  2. Inner Time and Inner Ear

    CERN Document Server

    Rvachov, Michael

    2012-01-01

    Sounds are information sequences that cannot exist outside of a time base and therefore cannot be analyzed inside an animal without an accurate internal clock. It is suggested that the clock may be hidden in the inner ear. It is shown that if a mechanism of counting of the electrical charge passing through the inner ear hair cells exists then the mechanism can be used both for the conversion of acceleration into velocity and as the inner clock, in the presence of a constant current. The causes of vertigo during rotation are discussed. It is shown that if a continuous inner time exists then sleeping is a mathematical necessity. It is indicated that both for visual and hearing inputs the recognition of an input signal is recognition of function(s) of two variables.

  3. [Inner Ear Hearing Loss].

    Science.gov (United States)

    Hesse, G

    2016-06-01

    Hearing loss is one of the most dominant handicaps in modern societies, which additionally very often is not realized or not admitted. About one quarter of the general population suffers from inner ear hearing loss and is therefore restricted in communicational skills. Demographic factors like increasing age play an important role as well as environmental influences and an increasing sound and noise exposure especially in leisure activities. Thus borders between a "classical" presbyacusis - if it ever existed - and envirionmentally induced hearing loss disappear. Today restrictions in hearing ability develop earlier in age but at the same time they are detected and diagnosed earlier. This paper can eventually enlighten the wide field of inner ear hearing loss only fragmentarily; therefore mainly new research, findings and developments are reviewed. The first part discusses new aspects of diagnostics of inner ear hearing loss and different etiologies.

  4. Inner ear disturbances related to middle ear inflammation

    Science.gov (United States)

    Sone, Michihiko

    2017-01-01

    ABSTRACT The inner and middle ear are connected mainly through round and oval windows, and inflammation in the middle ear cavity can spread into the inner ear, which might induce a disturbance. In cases with intractable otitis media, attention should also be paid to symptoms related to the inner ear. In this paper, middle ear inflammation and related inner ear disturbances are reviewed with a focus on representative middle ear diseases (such as acute otitis media, chronic otitis media, otitis media with anti-neutrophil cytoplasmic antibody-associated vasculitis, eosinophilic otitis media, cholesteatoma with labyrinthine fistula, and reflux-related otitis media). Their clinical concerns are then discussed with reference to experimental studies. In these diseases, early diagnosis and adequate treatment are required to manage not only middle ear but also inner ear conditions.

  5. Proteomics and the Inner Ear

    Directory of Open Access Journals (Sweden)

    Isolde Thalmann

    2001-01-01

    Full Text Available The inner ear, one of the most complex organs, contains within its bony shell three sensory systems, the evolutionary oldest gravity receptor system, the three semicircular canals for the detection of angular acceleration, and the auditory system - unrivaled in sensitivity and frequency discrimination. All three systems are susceptible to a host of afflictions affecting the quality of life for all of us. In the first part of this review we present an introduction to the milestones of inner ear research to pave the way for understanding the complexities of a proteomics approach to the ear. Minute sensory structures, surrounded by large fluid spaces and a hard bony shell, pose extreme challenges to the ear researcher. In spite of these obstacles, a powerful preparatory technique was developed, whereby precisely defined microscopic tissue elements can be isolated and analyzed, while maintaining the biochemical state representative of the in vivo conditions. The second part consists of a discussion of proteomics as a tool in the elucidation of basic and pathologic mechanisms, diagnosis of disease, as well as treatment. Examples are the organ of Corti proteins OCP1 and OCP2, oncomodulin, a highly specific calcium-binding protein, and several disease entities, Meniere's disease, benign paroxysmal positional vertigo, and perilymphatic fistula.

  6. INNER EAR EMBRYOGENESIS: GENETIC AND ENVIRONMENTAL DETERMINANTS

    Science.gov (United States)

    The anatomy and developmental molecular genetics of the inner ear from establishment of the otic placode to formation of the definitive cochlea and vestibular apparatus will be reviewed and the complex 3-D structural changes that shape the developing inner ear will be illustrated...

  7. Inner ear malformations: a practical diagnostic approach.

    Science.gov (United States)

    Mazón, M; Pont, E; Montoya-Filardi, A; Carreres-Polo, J; Más-Estellés, F

    Pediatric sensorineural hearing loss is a major cause of disability; although inner ear malformations account for only 20-40% of all cases, recognition and characterization will be vital for the proper management of these patients. In this article relevant anatomy and development of inner ear are surveyed. The role of neuroimaging in pediatric sensorineural hearing loss and cochlear preimplantation study are assessed. The need for a universal system of classification of inner ear malformations with therapeutic and prognostic implications is highlighted. And finally, the radiological findings of each type of malformation are concisely described and depicted. Computed tomography and magnetic resonance imaging play a crucial role in the characterization of inner ear malformations and allow the assessment of the anatomical structures that enable the selection of appropriate treatment and surgical approach. Copyright © 2016 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.

  8. The inner ear produces a natriuretic hormone

    DEFF Research Database (Denmark)

    Qvortrup, K; Rostgaard, J; Holstein-Rathlou, N H

    1996-01-01

    Cytoplasmic granules have been demonstrated in epithelial cells from the endolymphatic sac, an extraosseus part of the inner ear located in the posterior cranial fossa. Intravenously infused extracts from endolymphatic sacs in anesthetized rats elicited a potent natriuresis and diuresis without...... be the sensory organ/mediator of "cerebral" natriuresis. Furthermore, this substance, tentatively named saccin, may influence the homeostasis of the inner ear fluids and accordingly play a significant role in the pathogenesis of Mèniére's disease....

  9. CT of temporal bone - IV. inner ear

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    Kwon, Jae Yoon; Sung, Kyu Bo; Youn, Eun Kyoung; Park, Youn Kyeung; Lee, Young Uk [Koryo general Hospital, Seoul (Korea, Republic of)

    1990-07-15

    Temporal bone CT was done in 697 patients from April 1985 to October 1989. The abnormal findings were seen in 453 patients, which were chronic otitis media in 355 patients, fracture in 49 patients and congenital anomaly in 44 patients, etc. The abnormal findings of inner ear were observed on 46 patients. The results were summarized as follows : 1. The incidence of inner ear involvement by chronic otitis media was 7.3% (26/355 : labyrinthine fistula in 17 patients, labyrinthitis ossificans in 9 patients). Labyrinthine fistula was most commonly located on lateral semicircular canal (15/17, 88.2%). 2. Fusion of vestibule with lateral semicircular canal and formation of common cavity was demonstrated incidentally in 5 patients (0.7% of total number of temporal bone CT), and bilateral in 3 patients. 3. The incidence of inner ear anomaly in congenital ear anomaly was 11.4% (5/44). All cases were bilateral and three patients showed associated middle ear anomaly. 4. The incidence of involvement of bony labyrinth in temporal bone fracture was 10.2% (5/49). Labyrinthine fracture was seen all patients of transverse(3) and mixed fracture(1). In longitudinal fracture, labyrinthine fracture was seen in 2.2% (1/45). 5. Others were traumatic labyrinthitis ossificans(1), intracanalicular acoustic neuroma(3) and facial nerve neuroma(1)

  10. The Frog Inner Ear: Picture Perfect?

    OpenAIRE

    Mason, Matthew James; Segenhout, Johannes M.; Cobo-Cuan, Ariadna; Quiñones, Patricia M.; van Dijk, Pim

    2015-01-01

    This is the accepted manuscript of a paper published in the Journal of the Association for Research in Otolaryngology (2015) DOI: 10.1007/s10162-015-0506-z Many recent accounts of the frog peripheral auditory system have reproduced Wever’s (1973) schematic cross-section of the ear of a leopard frog. We sought to investigate to what extent this diagram is an accurate and representative depiction of the anuran inner ear, using three-dimensional reconstructions made from serial sections of Ra...

  11. Diving injuries to the inner ear.

    Science.gov (United States)

    Farmer, J C

    1977-01-01

    Most of the previous literature concerning otologic problems in compressed gas environments has emphasized middle ear barotrauma. With recent increases in commercial, military, and sport diving to deeper depths, inner ear disturbances during these exposures have been noted more frequently. Studies of inner ear physiology and pathology during diving indicate that the causes and treatment of these problems differ depending upon the phase and type of diving. Humans exposed to simulated depths of up to 305 meters without barotrauma or decompression sickness develop transient, conductive hearing losses with no audiometric evidence of cochlear dysfunction. Transient vertigo and nystagmus during diving have been noted with caloric stimulation, resulting from the unequal entry of cold water into the external auditory canals, and with asymmetric middle ear pressure equilibration during ascent and descent (alternobaric vertigo). Equilibrium disturbances noted with nitrogen narcosis, oxygen toxicity, hypercarbia, or hypoxia appear primarily related to the effects of these conditions upon the central nervous system and not to specific vestibular end-organ dysfunction. Compression of humans in helium-oxygen at depths greater than 152.4 meters results in transient symptoms of tremor, dizziness, and nausea plus decrements in postural equilibrium and psychomotor performance, the high pressure nervous syndrome. Vestibular function studies during these conditions indicate that these problems are due to central dysfunction and not to vestibular end-organ dysfunction. Persistent inner ear injuries have been noted during several phases of diving: 1) Such injuries during compression (inner ear barotrauma) have been related to round window ruptures occurring with straining, or a Valsalva's maneuver during inadequate middle ear pressure equilibration. Divers who develop cochlear and/or vestibular symptoms during shallow diving in which decompression sickness is unlikely or during

  12. [Imaging and audiology analysis of the congenital inner ear malformations].

    Science.gov (United States)

    Zhou, Bao; Lin, Shaolian; Lin, Youhui; Fang, Zheming; Ye, Shengnan; Zhang, Rong

    2015-11-01

    To investigate imaging and audiology features of temporal bone and analyze the classification and prevalence of inner ear abnormalities in children with sensorineural hearing loss. Children who were diagnosed with sensorineural hearing loss were examined by high resolution CT and the inner ear fluid of MRI. And each chart was retrospectively reviewed to determine the imaging and audiology features. There were 125 patients(232 ears) found with inner ear malformation in 590 children with SNHL. About 21.71% of the inner ear malformation occurred in severe and profound hearing loss ears, and 12.85% occurred in r moderate hearing loss ears. The inner ear malformation rate in normal hearing ears were 13.59%. CT and MRI examinations of temporal bone are important diagnostic tools to indentify inner ear malformations. Inner ear malformations are almost bilateral and hearing loss are profoud. Cochleo-vestibular malformations and large vestibular aqueduct are the 2 most frequent deformities. Among the children with SNHL, deformity rate in the severe and profound hearing loss ears is higher than that in moderate hearing loss ear. Inner ear malformations can exist in people with normal hearing.

  13. Change of guinea pig inner ear pressure by square wave middle ear cavity pressure variation

    NARCIS (Netherlands)

    Feijen, RA; Segenhout, JM; Albers, FWJ; Wit, HP

    The inner ear fluid pressure of guinea pigs was measured during square wave middle ear cavity pressure variation. Time constants were derived for the slopes of the inner ear pressure recovery curves after middle ear pressure change. A "single exponential" function did not fit well and therefore more

  14. Change of guinea pig inner ear pressure by square wave middle ear cavity pressure variation

    NARCIS (Netherlands)

    Feijen, RA; Segenhout, JM; Albers, FWJ; Wit, HP

    2002-01-01

    The inner ear fluid pressure of guinea pigs was measured during square wave middle ear cavity pressure variation. Time constants were derived for the slopes of the inner ear pressure recovery curves after middle ear pressure change. A "single exponential" function did not fit well and therefore more

  15. Current strategies for drug delivery to the inner ear

    Directory of Open Access Journals (Sweden)

    Hongzhuo Liu

    2013-04-01

    Full Text Available For many years, drug delivery to the inner ear has been a challenge to physicians in the treatment of inner ear disorders. In the past decade, the field of inner ear drug delivery has emerged with the development of new biomaterials and drug delivery technologies to improve the effectiveness of inner ear drug therapy. This paper reviews a number of inner ear drug delivery strategies including systemic, intratympanic, and intracochlear delivery. A focus of this review is the recent advances in intratympanic delivery of medications; approaches utilizing novel biomaterials as well as other recent developments are also discussed. Biotechnology-based approaches, such as gene and stem cell therapy methods are also reviewed. Among the various strategies, local drug delivery approaches including intratympanic and intracochlear drug delivery methods that limit systemic exposure are particularly promising. These inner ear drug delivery systems provide a new opportunity to improve the treatment of inner ear disorders.

  16. Autoimmune Inner Ear Disease- A Clinical Viewpoint

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    Amirala Khalessi

    2010-10-01

    Full Text Available Recent developments in medicine have given us a better insight into a group of disorders known as autoimmune diseases. In particular, advances have occurred in our understanding of the Autoimmune Inner Ear Disease (AIED. In this article, the authors review the different postulated theories in the pathogenesis of this disease. The clinical presentation, the available para-clinical diagnostic tools, and the important differential diagnoses will be summarized. The management methods, including steroid therapy, immunosuppressive medications, other biological agents and intra-tympanic injections, will be addressed. Cochlear implantation as a final solution to the advanced stages of the disease, causing total deafness, will also be discussed.

  17. [Recurrent meningitis in inner ear malformations].

    Science.gov (United States)

    Claros, Pedro; Matusialk, Monika

    2008-01-01

    Authors present two cases of children with reccurent meningitis and unilateral deafness. Implemented diagnostics (CT, NMR, ABR) revealed one side inner ear congenital malformation in one case and anterior fossa bony defect accompanied by labirynthine deformation in the other case. The presence of perilymphatic fistulae in oval and round windows and cerebrospinal fluid leakage has been confirmed in both cases during surgery. Carefull obliteration of the Eustachian tube and both windows has been performed. Non- complicated postoperative course (2 months and 6 years - respectively) has prooved the effectiveness of applied treatment.

  18. "COCHLEAR IMPLANTATION IN PATIENTS WITH INNER EAR MALFORMATIONS"

    OpenAIRE

    P. Borghei S. Abdi; M. Motesaddi Zari; Khalessi MH

    2004-01-01

    Performing cochlear implantation in patients with inner ear malformation has always been a matter of dispute. This study was designed to analyze the operative findings,complications, and postoperative performance of patients with inner ear anomalies who underwent cochlear implantation. Six patients with inner ear malformations underwent implantation in our academic tertiary referral center from 1997 to 2002. The average follow-up period was 27 months. Malformations included one incomplete par...

  19. Probing the Xenopus laevis inner ear transcriptome for biological function

    Directory of Open Access Journals (Sweden)

    Powers TuShun R

    2012-06-01

    Full Text Available Abstract Background The senses of hearing and balance depend upon mechanoreception, a process that originates in the inner ear and shares features across species. Amphibians have been widely used for physiological studies of mechanotransduction by sensory hair cells. In contrast, much less is known of the genetic basis of auditory and vestibular function in this class of animals. Among amphibians, the genus Xenopus is a well-characterized genetic and developmental model that offers unique opportunities for inner ear research because of the amphibian capacity for tissue and organ regeneration. For these reasons, we implemented a functional genomics approach as a means to undertake a large-scale analysis of the Xenopus laevis inner ear transcriptome through microarray analysis. Results Microarray analysis uncovered genes within the X. laevis inner ear transcriptome associated with inner ear function and impairment in other organisms, thereby supporting the inclusion of Xenopus in cross-species genetic studies of the inner ear. The use of gene categories (inner ear tissue; deafness; ion channels; ion transporters; transcription factors facilitated the assignment of functional significance to probe set identifiers. We enhanced the biological relevance of our microarray data by using a variety of curation approaches to increase the annotation of the Affymetrix GeneChip® Xenopus laevis Genome array. In addition, annotation analysis revealed the prevalence of inner ear transcripts represented by probe set identifiers that lack functional characterization. Conclusions We identified an abundance of targets for genetic analysis of auditory and vestibular function. The orthologues to human genes with known inner ear function and the highly expressed transcripts that lack annotation are particularly interesting candidates for future analyses. We used informatics approaches to impart biologically relevant information to the Xenopus inner ear transcriptome

  20. [Effects of noise on inner ear].

    Science.gov (United States)

    Bouccara, Didier; Ferrary, Evelyne; Sterkers, Olivier

    2006-11-01

    The effects of noise on health depend both on individual factors and characteristics of sound exposure. In case of acoustic trauma, reversible or irreversible lesions of inner ear components are possible. Most often there is immediately an acute tinnitus and hearing loss. Audiometric tests demonstrate hearing loss on the high frequency, generally focused on 4 kHz. Immediate treatment is recommended even there is no currently indicator of the ability to restore hearing. New perspectives on treatment are directed to local treatment and/or using new procedure as antioxidative treatment. Occupational and leisure are the two conditions in which chronic exposure to noise is found. Detection and prevention of noise-induced hearing loss is easier in case of industrial workers than in case of noise exposition for musicians and other sounds and stage technicians or concert managers, and of course non-professional with exposure to amplified music.

  1. Otosclerosis associated with type B-1 inner ear malformation.

    Science.gov (United States)

    De Stefano, A; Dispenza, F; Aggarwal, N; Russo, A

    2010-06-01

    Malformations of bony inner ear are rare anomalies occurring in approximately 20% of patients with congenital sensorineural hearing loss. Conductive hearing loss is usually associated with abnormalities of the external and middle ear. Recent reports of patients with lateral semicircular canal malformations indicate inner ear malformations to be associated with sensorineural or conductive hearing loss. Differential diagnosis of conductive hearing loss should include otosclerosis, isolated ossicular deformities, inner ear anomalies or a combination of these. In this report, a case is described with right vestibule-lateral semicircular canal dysplasia presenting at our centre with bilateral otosclerosis.

  2. [The progress of inner ear malformation in radiological research].

    Science.gov (United States)

    Kong, Dehua; Fu, Kuang; Zhao, Hui

    2016-01-01

    Inner ear malformations are anomalies linking to development insults at different periods of embryogenesis,which are common causes of congenital sensorineural hearing loss. The evaluation of pediatric sensorineural hearing loss mostly depends on high-resolution computed tomography and magnetic resonance imaging, which can excellently depict the temporal bones and inner ear malformations.

  3. Otosclerosis associated with type B-1 inner ear malformation

    OpenAIRE

    De Stefano, A.; DISPENZA, F.; Aggarwal, N.; Russo, A.

    2010-01-01

    Malformations of bony inner ear are rare anomalies occurring in approximately 20% of patients with congenital sensorineural hearing loss. Conductive hearing loss is usually associated with abnormalities of the external and middle ear. Recent reports of patients with lateral semicircular canal malformations indicate inner ear malformations to be associated with sensorineural or conductive hearing loss. Differential diagnosis of conductive hearing loss should include otosclerosis, isolated ossi...

  4. LDV measurement of bird ear vibrations to determine inner ear impedance and middle ear power flow

    Science.gov (United States)

    Muyshondt, Pieter G. G.; Pires, Felipe; Dirckx, Joris J. J.

    2016-06-01

    The mechanical behavior of the middle ear structures in birds and mammals is affected by the fluids in the inner ear (IE) that are present behind the oval window. In this study, the aim was to gather knowledge of the acoustic impedance of the IE in the ostrich, to be able to determine the effect on vibrations and power flow in the single-ossicle bird middle ear for future studies. To determine the IE impedance, vibrations of the ossicle were measured for both the quasi-static and acoustic stimulus frequencies. In the acoustic regime, vibrations were measured with a laser Doppler vibrometer and electromagnetic stimulation of the ossicle. The impedance of the inner ear could be determined by means of a simple RLC model in series, which resulted in a stiffness reactance of KIE = 0.20.1012 Pa/m3, an inertial impedance of MIE = 0.652.106 Pa s2/m3, and a resistance of RIE = 1.57.109 Pa s/m. The measured impedance is found to be considerably smaller than what is found for the human IE.

  5. Inner ear contribution to bone conduction hearing in the human.

    Science.gov (United States)

    Stenfelt, Stefan

    2015-11-01

    Bone conduction (BC) hearing relies on sound vibration transmission in the skull bone. Several clinical findings indicate that in the human, the skull vibration of the inner ear dominates the response for BC sound. Two phenomena transform the vibrations of the skull surrounding the inner ear to an excitation of the basilar membrane, (1) inertia of the inner ear fluid and (2) compression and expansion of the inner ear space. The relative importance of these two contributors were investigated using an impedance lumped element model. By dividing the motion of the inner ear boundary in common and differential motion it was found that the common motion dominated at frequencies below 7 kHz but above this frequency differential motion was greatest. When these motions were used to excite the model it was found that for the normal ear, the fluid inertia response was up to 20 dB greater than the compression response. This changed in the pathological ear where, for example, otosclerosis of the stapes depressed the fluid inertia response and improved the compression response so that inner ear compression dominated BC hearing at frequencies above 400 Hz. The model was also able to predict experimental and clinical findings of BC sensitivity in the literature, for example the so called Carhart notch in otosclerosis, increased BC sensitivity in superior semicircular canal dehiscence, and altered BC sensitivity following a vestibular fenestration and RW atresia.

  6. A potential portal flow in the inner ear

    DEFF Research Database (Denmark)

    Friis, Morten; Qvortrup, Klaus

    2007-01-01

    . The endolymphatic sac has been implicated as a potential endocrine gland, which venules drain to the VVA. A reversal of the direction of flow in the VVA toward the inner ear could, through vestibular arteriovenous anastomosis, cause portal circulation in the inner ear. STUDY DESIGN: The authors conducted...... an experimental animal study using in vivo fluorescence microscopy. RESULTS: Obstructing the distal part of the VVA just before it empties into the sigmoid sinus immediately reverses the flow of blood in the VVA toward the inner ear. CONCLUSIONS: After an obstruction of the VVA, the drained venous blood from...... the endolymphatic sac may enter a portal circulation in the inner ear, which could cause disturbances in the endolymph homeostasis and potentially symptoms as seen in Meniere disease....

  7. Congenital inner ear malformations without sensorineural hearing loss.

    Science.gov (United States)

    Yukawa, Kumiko; Horiguchi, Satoshi; Suzuki, Mamoru

    2008-03-01

    It has been reported that normal hearing is rare in patients with severe inner ear vestibular malformations [Kokai H, Oohashi M, Ishikawa K, Harada K, Hiratsuka H, Ogasawara M et al. Clinical review of inner ear malformation. J Otolaryngol Jpn 2003;106(10):1038-44; Schuknecht HF. Mondini dysplasia. A clinical pathological study. Ann Otol Rhinol Laryngol 1980;89(Suppl. 65):1-23; Jackler RK, Luxford WM, House WF. Congenital malformations of the inner ear: a classification based on embryogenesis. Laryngoscope 1987;97:2-14; Phelps PD. Congenital lesions of the inner ear, demonstrated by tomography. Arch Otolaryngol 1974;100:11-8]. A 37-year-old woman had combined dysplasia of the posterior and lateral semicircular canals (PSCC, LSCC) with normal cochlear development and normal hearing in both ears. She had complained of dizziness for 8 months. High resolution computed tomography (CT) showed hypogenesis of the bony labyrinth in both ears. Bilateral PSCC and LSCC dysplasia and dilatation of the vestibule were detected. Magnetic resonant imaging (MRI) revealed that the deformity of the PSCC was more severe than the LSCC. Although the caloric test of the left ear elicited no nystagmus and there was reduced response in the right ear, the horizontal vestibulo-occular reflex (VOR) was present. Her dizzy sensation disappeared within 3 months without special treatment. The dizziness attack might have been caused by a temporary breakdown of her peripheral vestibular system.

  8. Revision Stapedectomy in a Female Patient with Inner Ear Malformation

    Directory of Open Access Journals (Sweden)

    Tirth R. Patel

    2016-01-01

    Full Text Available Objectives. We describe an unusual case of surgical management of congenital mixed hearing loss in a female patient with inner ear malformation. This report outlines the role of temporal bone imaging and previous surgical history in evaluating a patient’s risk of perilymph gusher during stapes surgery. Methods. A 68-year-old female patient with a history of profound bilateral mixed hearing loss due to ossicular and cochlear malformation presented to our otology clinic. She had undergone multiple unsuccessful previous ear surgeries. Computed tomography revealed bilateral inner ear malformations. She elected to proceed with revision stapedectomy. Results. The patient received modest benefit to hearing, and no operative complications occurred. Conclusions. Although stapedectomy has been shown to improve hearing in patients with stapes fixation, there is risk of perilymph gusher in patients with inner ear abnormalities. Evaluation and counseling of the risk of gusher during stapes surgery should be done on a case-by-case basis.

  9. [Cochlear implant for malformations of the inner ear].

    Science.gov (United States)

    Aschendorff, A; Laszig, R; Maier, W; Beck, R; Schild, C; Birkenhäger, R; Wesarg, T; Kröger, S; Arndt, S

    2009-06-01

    The radiologic evaluation of the temporal bone in cochlear implant candidates can detect malformations of the inner ear in up to 20% of cases. The aim of our study was to analyze and classify malformations of the inner ear in patients with cochlear implants carried out from 2001 to 2009. Malformations of the inner ear, including malformations of the internal auditory canal were detected in 12.7% of children and 3.4% of adults. Mondini dysplasia was most common and occurred in 45% of cases. The surgical procedure had to be adapted according to the individual malformation. Modification of surgical access, management of intraoperative CSF gusher, choice of electrode array, intraoperative imaging and the use of navigation were the most important factors. Rehabilitation results were generally very positive and corresponded to the expectation depending on the duration of deafness, if no additional handicaps were present.

  10. Statistical shape model with random walks for inner ear segmentation

    DEFF Research Database (Denmark)

    Pujadas, Esmeralda Ruiz; Kjer, Hans Martin; Piella, Gemma

    2016-01-01

    Cochlear implants can restore hearing to completely or partially deaf patients. The intervention planning can be aided by providing a patient-specific model of the inner ear. Such a model has to be built from high resolution images with accurate segmentations. Thus, a precise segmentation...... is required. We propose a new framework for segmentation of micro-CT cochlear images using random walks combined with a statistical shape model (SSM). The SSM allows us to constrain the less contrasted areas and ensures valid inner ear shape outputs. Additionally, a topology preservation method is proposed...

  11. Congenital inner ear malformations without sensorineural hearing loss in children.

    Science.gov (United States)

    Ozeki, Michio; Kato, Zenichiro; Sasai, Hideo; Kubota, Kazuo; Funato, Michinori; Orii, Kenji; Kaneko, Hideo; Fukao, Toshiyuki; Kondo, Naomi

    2009-10-01

    Inner ear malformations are frequently found in patients with congenital hearing loss. It has been reported that normal hearing is rare in patients with severe inner ear vestibular malformations. A 9-year-old boy had had complained of recurrent dizziness and disequilibrium for 2 months. Clinical and neuro-otological examinations showed peripheral involvement of the vestibular system, while audiological investigation was normal. High-resolution magnetic resonance imaging, with three-dimensional reconstruction, showed dysplasia of the bilateral lateral semicircular canals (LSCCs). Isolated vestibular malformation might not be as rare as previously thought, and should be examined by imaging of the temporal bone.

  12. Inner ear supporting cells: rethinking the silent majority.

    Science.gov (United States)

    Wan, Guoqiang; Corfas, Gabriel; Stone, Jennifer S

    2013-05-01

    Sensory epithelia of the inner ear contain two major cell types: hair cells and supporting cells. It has been clear for a long time that hair cells play critical roles in mechanoreception and synaptic transmission. In contrast, until recently the more abundant supporting cells were viewed as serving primarily structural and homeostatic functions. In this review, we discuss the growing information about the roles that supporting cells play in the development, function and maintenance of the inner ear, their activities in pathological states, their potential for hair cell regeneration, and the mechanisms underlying these processes. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Nonlinear dynamics of the mammalian inner ear

    CERN Document Server

    Szalai, Robert; Homer, Martin

    2015-01-01

    A simple nonlinear transmission-line model of the cochlea with longitudinal coupling is introduced that can reproduce Basilar membrane response and neural tuning in the chinchilla. It is found that the middle ear has little effect on cochlear resonances, and hence conclude that the theory of coherent reflections is not applicable to the model. The model also provides an explanation of the emergence of spontaneous otoacoustic emissions (SOAEs). It is argued that SOAEs arise from Hopf bifurcations of the transmission-line model and not from localized instabilities. The paper shows that emissions can become chaotic, intermittent and fragile to perturbations.

  14. Inner ear pressure changes following square wave intracranial or ear canal pressure manipulation in the same guinea pig

    NARCIS (Netherlands)

    Thalen, E; Wit, H; Segenhout, H; Albers, F

    Inner ear pressure was measured in scala tympani with a micropipette during square wave pressure manipulation of the intracranial compartment and, subsequently, of the external ear canal (EEC) in the same guinea pig. As expected, the combination of the cochlear aqueduct and the inner ear behaves as

  15. Three-dimensional reconstruction of the pigeon inner ear

    NARCIS (Netherlands)

    Hofman, R.; Segenhout, J. M.; Wit, H. P.

    2009-01-01

    Three-dimensional reconstructions of the inner ear of the pigeon (Columba livia domestica), from two-dimensional images, obtained with (conventional) light microscopy or orthogonal-plane fluorescence optical sectioning (OPFOS), are presented. The results are compared with available information on th

  16. Does improved hearing result in altered inner ear morphology?

    Directory of Open Access Journals (Sweden)

    Tanja Schulz-Mirbach

    2015-10-01

    Full Text Available The sense of hearing plays an important role for fishes to obtain information about their (acoustic environment (e.g. Popper 2011, Fay 2011. In numerous taxa, ancillary auditory structures like swimbladder modifications evolved, leading to an improved audition (Braun and Grande 2008. Despite a profound knowledge of inner ear diversity and ancillary auditory structures (for an overview see Schulz-Mirbach and Ladich 2015, Ladich 2015, the relationship between the morphology of these structures and hearing abilities remains to be elucidated. We tested the hypothesis that swimbladder modifications coincide with differences in inner ear morphology, using cichlids as a model because they show considerable intrafamilial diversity in swimbladder morphology and hearing capabilities (Schulz-Mirbach et al. 2012, 2014. We compared Steatocranus tinanti (vestigial swimbladder, Hemichromis guttatus (large swimbladder without extensions, and Etroplus maculatus (intimate connection between swimbladder and inner ears by applying immunostaining together with confocal imaging for the investigation of sensory epithelia, and high-resolution, contrast enhanced microCT imaging for characterizing inner ears in 3D. Compared to S. tinanti and H. guttatus, inner ears of E. maculatus showed an enlargement of all three maculae, and a particularly large lacinia of the macula utriculi. While our analysis of orientation patterns of ciliary bundles on the three macula types using artificially flattened maculae uncovered rather similar orientation patterns of ciliary bundles, interspecific differences became apparent when illustrating the orientation patterns on the 3D models of the maculae: differences in the shape and curvature of the lacinia of the macula utriculi, and the anterior arm of the macula lagenae resulted in an altered arrangement of ciliary bundles. Our results imply that improved hearing in E. maculatus is associated not only with swimbladder modifications but

  17. "COCHLEAR IMPLANTATION IN PATIENTS WITH INNER EAR MALFORMATIONS"

    Directory of Open Access Journals (Sweden)

    P. Borghei S. Abdi

    2004-08-01

    Full Text Available Performing cochlear implantation in patients with inner ear malformation has always been a matter of dispute. This study was designed to analyze the operative findings,complications, and postoperative performance of patients with inner ear anomalies who underwent cochlear implantation. Six patients with inner ear malformations underwent implantation in our academic tertiary referral center from 1997 to 2002. The average follow-up period was 27 months. Malformations included one incomplete partition, one common cavity, one narrow internal acoustic canal (IAC in a patient with Riley-Day syndrome and 3 cases of large vestibular aqueduct. All received multi-channel implants either Nucleus 22 or Clarion device. Facial nerve was anomalous in 2 cases. CSF gusher occurred in 4 patients, which was controlled with packing the cochleostomy site. In all cases, the full length of electrode array was inserted, except one with Mondini's dysplasia where insertion failed in the first operation and was referred to another center for a successful surgery on the opposite ear. No other surgical complications were encountered. In 4 cases, all the 22 electrodes could be activated. All patients showed improved hearing performance after implantation. Four showed open-set speech recognition. The one with narrow IAC showed improved awareness to environmental sounds. In the other case (common cavity, the perception tests could not be performed because of very young age. Cochlear implantation in patients with inner ear malformations is a successful way of rehabilitation, although complications should be expected and auditory responses may be highly variable and relatively moderate.

  18. Revision Stapedectomy in a Female Patient with Inner Ear Malformation

    OpenAIRE

    Patel, Tirth R.; Moberly, Aaron C.

    2016-01-01

    Objectives. We describe an unusual case of surgical management of congenital mixed hearing loss in a female patient with inner ear malformation. This report outlines the role of temporal bone imaging and previous surgical history in evaluating a patient’s risk of perilymph gusher during stapes surgery. Methods. A 68-year-old female patient with a history of profound bilateral mixed hearing loss due to ossicular and cochlear malformation presented to our otology clinic. She had undergone multi...

  19. Prevalence of inner ear anomalies among cochlear implant candidates

    OpenAIRE

    Aldhafeeri, Ahmad M.; Alsanosi, Abdulrahman A.

    2016-01-01

    Objectives: To determine the prevalence of inner ear anomalies and the frequency of different anomaly types among cochlear implant recipients. Methods: This study included a retrospective chart review of all patients who received cochlear implants between January 2009 and January 2013 in King Abdulaziz University Hospital cochlear implant program in Riyadh, Saudi Arabia. All subjects underwent thin-cut CT of the temporal bone and MRI. The collected data included age, gender, and CT and MRI fi...

  20. Hair cell bundles: flexoelectric motors of the inner ear.

    Directory of Open Access Journals (Sweden)

    Kathryn D Breneman

    Full Text Available Microvilli (stereocilia projecting from the apex of hair cells in the inner ear are actively motile structures that feed energy into the vibration of the inner ear and enhance sensitivity to sound. The biophysical mechanism underlying the hair bundle motor is unknown. In this study, we examined a membrane flexoelectric origin for active movements in stereocilia and conclude that it is likely to be an important contributor to mechanical power output by hair bundles. We formulated a realistic biophysical model of stereocilia incorporating stereocilia dimensions, the known flexoelectric coefficient of lipid membranes, mechanical compliance, and fluid drag. Electrical power enters the stereocilia through displacement sensitive ion channels and, due to the small diameter of stereocilia, is converted to useful mechanical power output by flexoelectricity. This motor augments molecular motors associated with the mechanosensitive apparatus itself that have been described previously. The model reveals stereocilia to be highly efficient and fast flexoelectric motors that capture the energy in the extracellular electro-chemical potential of the inner ear to generate mechanical power output. The power analysis provides an explanation for the correlation between stereocilia height and the tonotopic organization of hearing organs. Further, results suggest that flexoelectricity may be essential to the exquisite sensitivity and frequency selectivity of non-mammalian hearing organs at high auditory frequencies, and may contribute to the "cochlear amplifier" in mammals.

  1. Fgf19 expression patterns in the developing chick inner ear.

    Science.gov (United States)

    Sánchez-Calderón, Hortensia; Francisco-Morcillo, Javier; Martín-Partido, Gervasio; Hidalgo-Sánchez, Matías

    2007-01-01

    The inner ear is a complex sensorial structure with hearing and balance functions. A key aim of developmental biology is to understand the molecular and cellular mechanisms involved in the induction, patterning and innervation of the vertebrate inner ear. These developmental events could be mediated by the expression of regulating genes, such as the members of the family of Fibroblast Growth Factors (Fgfs). This work reports the detailed spatial and temporal patterns of Fgf19 expression in the developing inner ear from otic cup (stage 14) to 8 embryonic days (stage 34). In the earliest stages, Fgf19 and Fgf8 expressions determine two subdomains within the Fgf10-positive proneural-sensory territory. We show that, from the earliest stages, the Fgf19 expression was detected in the acoustic-vestibular ganglion and the macula utriculi. The Fgf19 gene was also strongly, but transiently, expressed in the macula lagena, whereas the macula neglecta never expressed this gene in the period analysed. The Fgf19 expression was also clearly observed in some borders of various sensory elements. These results could be useful from further investigations into the role of FGF19 in otic patterning.

  2. Inner ear barriers to nanomedicine-augmented drug delivery and imaging

    Directory of Open Access Journals (Sweden)

    Jing Zou

    2016-12-01

    Full Text Available There are several challenges to inner ear drug delivery and imaging due to the existence of tight biological barriers to the target structure and the dense bone surrounding it. Advances in imaging and nanomedicine may provide knowledge for overcoming the existing limitations to both the diagnosis and treatment of inner ear diseases. Novel techniques have improved the efficacy of drug delivery and targeting to the inner ear, as well as the quality and accuracy of imaging this structure. In this review, we will describe the pathways and biological barriers of the inner ear regarding drug delivery, the beneficial applications and limitations of the imaging techniques available for inner ear research, the behavior of engineered nanomaterials in inner ear applications, and future perspectives for nanomedicine-based inner ear imaging.

  3. Dissecting the frog inner ear with Gaussian noise .2. Temperature dependence of inner ear function

    NARCIS (Netherlands)

    vanDijk, P; Wit, HP; Segenhout, JM

    1997-01-01

    The temperature dependence of the response of single primary auditory nerve fibers (n = 31) was investigated in the European edible frog, Rana esculenta (seven ears). Nerve fiber responses were analyzed with Wiener kernel analysis and polynomial correlation. The responses were described with a casca

  4. Inner ear of the coelacanth fish Latimeria has tetrapod affinities.

    Science.gov (United States)

    Fritzsch, B

    Auditory reception in elasmobranchs, teleosts and amphibians may be mediated by various inner-ear sensory epithelia 1–3, including the basilar papilla, which seems to be the precursor of the cochlea in mammals. The origin of the basilar papilla remains a major unsolved problem for understanding the evolution of hearing in terrestrial vertebrates4–6. Study of living species indicates that the basilar papilla is a unique feature of tetrapods 6,7, but palaeonto-logical data indicate that this epithelium as well as a middle ear, is already present in crossopterygian fish 8–10. However, no basilar papilla has been found in the only living crossopterygian species, the coelacanth Latimeria chalumnae 11. I have re-examined the inner ear of adult and embryonic Latimeria and find a membranous specialization which resembles in structure, position and innerva-tion pattern the basilar papilla of tetrapods, in particular amniotes. No epithelium comparable to the basilar papilla was found in lungfish. I suggest that the basilar papillae of Latimeria and tetrapods are homologous and evolved only once in their common ancestor.

  5. Energy extraction from the biologic battery in the inner ear.

    Science.gov (United States)

    Mercier, Patrick P; Lysaght, Andrew C; Bandyopadhyay, Saurav; Chandrakasan, Anantha P; Stankovic, Konstantina M

    2012-12-01

    Endocochlear potential (EP) is a battery-like electrochemical gradient found in and actively maintained by the inner ear. Here we demonstrate that the mammalian EP can be used as a power source for electronic devices. We achieved this by designing an anatomically sized, ultra-low quiescent-power energy harvester chip integrated with a wireless sensor capable of monitoring the EP itself. Although other forms of in vivo energy harvesting have been described in lower organisms, and thermoelectric, piezoelectric and biofuel devices are promising for mammalian applications, there have been few, if any, in vivo demonstrations in the vicinity of the ear, eye and brain. In this work, the chip extracted a minimum of 1.12 nW from the EP of a guinea pig for up to 5 h, enabling a 2.4 GHz radio to transmit measurement of the EP every 40-360 s. With future optimization of electrode design, we envision using the biologic battery in the inner ear to power chemical and molecular sensors, or drug-delivery actuators for diagnosis and therapy of hearing loss and other disorders.

  6. Cisplatin Ototoxicity Blocks Sensory Regeneration in the Avian Inner Ear

    Science.gov (United States)

    Slattery, Eric L.; Warchol, Mark E.

    2010-01-01

    Cisplatin is a chemotherapeutic agent that is widely-used in the treatment of solid tumors. Ototoxicity is a common side effect of cisplatin therapy, and often leads to permanent hearing loss. The sensory organs of the avian ear are able to regenerate hair cells after aminoglycoside ototoxicity. This regenerative response is mediated by supporting cells, which serve as precursors to replacement hair cells. Given the antimitotic properties of cisplatin, we examined whether the avian ear was also capable of regeneration after cisplatin ototoxicity. Using cell and organ cultures of the chick cochlea and utricle, we found that cisplatin treatment caused apoptosis of both auditory and vestibular hair cells. Hair cell death in the cochlea occurred in a unique pattern, progressing from the low frequency (distal) region toward the high frequency (proximal) region. We also found that cisplatin caused a dose-dependent reduction in the proliferation of cultured supporting cells as well as increased apoptosis in those cells. As a result, we observed no recovery of hair cells after ototoxic injury caused by cisplatin. Finally, we explored the potential for nonmitotic hair cell recovery via activation of Notch pathway signaling. Treatment with the γ-secretase inhibitor DAPT failed to promote the direct transdifferentiation of supporting cells into hair cells in cisplatin-treated utricles. Taken together, our data show that cisplatin treatment causes maintained changes to inner ear supporting cells and severely impairs the ability of the avian ear to regenerate either via proliferation or by direct transdifferentiation. PMID:20203207

  7. Chinchilla middle-ear admittance and sound power: high-frequency estimates and effects of inner-ear modifications.

    Science.gov (United States)

    Ravicz, Michael E; Rosowski, John J

    2012-10-01

    The middle-ear input admittance relates sound power into the middle ear (ME) and sound pressure at the tympanic membrane (TM). ME input admittance was measured in the chinchilla ear canal as part of a larger study of sound power transmission through the ME into the inner ear. The middle ear was open, and the inner ear was intact or modified with small sensors inserted into the vestibule near the cochlear base. A simple model of the chinchilla ear canal, based on ear canal sound pressure measurements at two points along the canal and an assumption of plane-wave propagation, enables reliable estimates of Y(TM,) the ME input admittance at the TM, from the admittance measured relatively far from the TM. Y(TM) appears valid at frequencies as high as 17 kHz, a much higher frequency than previously reported. The real part of Y(TM) decreases with frequency above 2 kHz. Effects of the inner-ear sensors (necessary for inner ear power computation) were small and generally limited to frequencies below 3 kHz. Computed power reflectance was ~0.1 below 3.5 kHz, lower than with an intact ME below 2.5 kHz, and nearly 1 above 16 kHz.

  8. Manufacturing and in vivo inner ear visualization of MRI traceable liposome nanoparticles encapsulating gadolinium

    Directory of Open Access Journals (Sweden)

    Kinnunen Paavo KJ

    2010-12-01

    Full Text Available Abstract Background Treatment of inner ear diseases remains a problem because of limited passage through the blood-inner ear barriers and lack of control with the delivery of treatment agents by intravenous or oral administration. As a minimally-invasive approach, intratympanic delivery of multifunctional nanoparticles (MFNPs carrying genes or drugs to the inner ear is a future therapy for treating inner ear diseases, including sensorineural hearing loss (SNHL and Meniere's disease. In an attempt to track the dynamics and distribution of nanoparticles in vivo, here we describe manufacturing MRI traceable liposome nanoparticles by encapsulating gadolinium-tetra-azacyclo-dodecane-tetra-acetic acid (Gd-DOTA (abbreviated as LPS+Gd-DOTA and their distribution in the inner ear after either intratympanic or intracochlear administration. Results Measurements of relaxivities (r1 and r2 showed that LPS+Gd-DOTA had efficient visible signal characteristics for MRI. In vivo studies demonstrated that LPS+Gd-DOTA with 130 nm size were efficiently taken up by the inner ear at 3 h after transtympanic injection and disappeared after 24 h. With intracochlear injection, LPS+Gd-DOTA were visualized to distribute throughout the inner ear, including the cochlea and vestibule with fast dynamics depending on the status of the perilymph circulation. Conclusion Novel LPS+Gd-DOTA were visible by MRI in the inner ear in vivo demonstrating transport from the middle ear to the inner ear and with dynamics that correlated to the status of the perilymph circulation.

  9. Measurements of normal inner ear on computed tomography in children with congenital sensorineural hearing loss.

    Science.gov (United States)

    Lan, Ming-Ying; Shiao, Jiun-Yih; Ho, Ching-Yin; Hung, Hao-Chun

    2009-09-01

    The objective of this study is to use standardized measurements of the inner ear to see whether there are subtle bony malformations in children with congenital sensorineural hearing loss (SNHL) whose temporal bone computed tomography (CT) are grossly normal. The study includes 45 ears with congenital SNHL and grossly normal temporal bone CT scans and 45 ears with normal inner ear structures and normal hearing. Standardized measurements of the inner ear structures were made on axial temporal bone CT scans. Student's t test was performed to compare the measurements of the two groups. There were significant differences in the measurements of the bony island width of the superior semicircular canal, bony island width of the lateral semicircular canal and maximal height of cochlea between two groups (P inner ear on temporal bone CT can identify subtle abnormalities of inner ear in patients with congenital SNHL having grossly normal radiological images.

  10. Applications of scanning electron microscopy and X-ray microanalysis in inner ear pathology

    Energy Technology Data Exchange (ETDEWEB)

    Anniko, M.; Lim, D.J.; Sobin, A.; Wroblewski, R.

    1985-01-01

    Surface pathology of inner ear structures so far described in detail concern cochlear and vestibular hair cells and the stria vascularis. In man, surgical intervention into the inner ear is very uncommon and when performed is in general with the primary objective of destroying the diseased peripheral end organs. The vast majority of inner ear tissue available for use with scanning electron microscopy (SEM) is therefore obtained from animals. The present paper reviews the progression of surface pathology caused by aminoglycoside antibiotics, acoustic overstimulation and in a guinea pig strain with genetic inner ear disease. The primary site of onset of surface pathology differs, depending on the underlying cause. Advanced surface pathology shows a similar type of morphological degeneration independent of cause. The combination of SEM and energy dispersive X-ray microanalysis (XRMA) of inner ear pathology has as yet been reported in only three studies, all concerning inner ear fluids or otoconia.

  11. Cochlear implantation in inner ear malformations--a review article.

    Science.gov (United States)

    Sennaroglu, Levent

    2010-03-01

    Inner ear malformations constitute about 20% of congenital sensorineural hearing loss. In this review article an updated classification of cochlear malformations is provided. Incomplete partition and cochlear hypoplasia cases are each divided further into three groups. There are two main difficulties in the surgery of inner ear malformations; gusher and facial nerve abnormalities. Radiological features of malformations necessary to identify these problems preoperatively are discussed. Facial nerve abnormalities that may occur are described. Two different types of cerebrospinal fluid leakage are defined and necessary measures to prevent leakage are described. Standard and modified surgical approaches to overcome the described problems are described with literature findings. Finally meningitis which may occur with and without cochlear implantation in this special group of patients is emphasized. This is common in incomplete partition type I patients and is usually due to a fistula in one of the windows (usually oval window) which occurs as a result of cerebrospinal fluid pressure. This is a medical emergency leading to potential meningitis and measures that should be taken to stop the leak as soon as possible are described.

  12. Imaging of the inner ear; Bildgebung des Innenohrs

    Energy Technology Data Exchange (ETDEWEB)

    Casselman, J.W. [Dept. of Radiology, A.Z.St.-Jan Brugge (Belgium); Bensimon, J.L. [Imagerie O.R.L. et Generale, Paris (France)

    1997-12-01

    New computed tomography (CT) and magnetic resonance (MR) techniques allow more detailed anatomic studies of the inner ear. CT is still the best technique to study patients with fractures, congenital malformations and otodystrophies involving the inner ear. During recent years MR imaging has emerged as an excellent method to detect pathology in the internal auditory canal, membranous labyrinth and bony labyrinth and to characterize petrous apex lesions. MR has even proved its value in patients with fractures and congenital malformations making the diagnosis of, for instance, labyrinthine concussion and absence of the vestibulocochlear nerve possible. The diagnosis of acute/chronic labyrinthitis and intralabyrinthine tumors has also became possible. However, MR and CT are often complementary, as is the case in patients with mixed hearing loss, congenital malformations and petrous apex lesions. (orig.) [Deutsch] Neuere CT- und MR-Untersuchungsmethoden erlauben eine detaillierte anatomische Darstellung des Innenohres. Die CT ist unveraendert die beste Bildgebungstechnik zur Darstellung von Frakturen, angeborenen Missbildungen und Otodystrophien im Innenohr. In den letzten Jahren hat sich die MRT im Nachweis pathologischer Veraenderungen von innerem Gehoergang, membranoesem und knoechernem Labyrinth und zur Charakterisierung von Schlaefenbeinspitzenlaesionen als diagnostisch aeusserst wertvoll erwiesen. Bei Patienten mit Frakturen oder kongenitalen Missbildungen erlaubt die MRT den Nachweis von labyrinthaeren Kontusionen bzw. Aplasie des vestibulocochlearen Nervs. Die Diagnose einer Labyrinthitis sowie von intralabyrinthaeren Tumoren wurde erstmals bildgebend mittels MRT moeglich. Es muss aber betont werden, dass MRT und CT meist komplementaere Methoden sind. Dies trifft insbesondere bei Patienten mit gemischtem Hoerverlust, kongenitalen Missbildungen und Schlaefenbeinapexlaesionen zu. (orig.)

  13. Inner ear dysfunction in caspase-3 deficient mice

    Directory of Open Access Journals (Sweden)

    Woo Minna

    2011-10-01

    Full Text Available Abstract Background Caspase-3 is one of the most downstream enzymes activated in the apoptotic pathway. In caspase-3 deficient mice, loss of cochlear hair cells and spiral ganglion cells coincide closely with hearing loss. In contrast with the auditory system, details of the vestibular phenotype have not been characterized. Here we report the vestibular phenotype and inner ear anatomy in the caspase-3 deficient (Casp3-/- mouse strain. Results Average ABR thresholds of Casp3-/- mice were significantly elevated (P Casp3+/- mice and Casp3+/+ mice at 3 months of age. In DPOAE testing, distortion product 2F1-F2 was significantly decreased (P Casp3-/- mice, whereas Casp3+/- and Casp3+/+ mice showed normal and comparable values to each other. Casp3-/- mice were hyperactive and exhibited circling behavior when excited. In lateral canal VOR testing, Casp3-/- mice had minimal response to any of the stimuli tested, whereas Casp3+/- mice had an intermediate response compared to Casp3+/+ mice. Inner ear anatomical and histological analysis revealed gross hypomorphism of the vestibular organs, in which the main site was the anterior semicircular canal. Hair cell numbers in the anterior- and lateral crista, and utricle were significantly smaller in Casp3-/- mice whereas the Casp3+/- and Casp3+/+ mice had normal hair cell numbers. Conclusions These results indicate that caspase-3 is essential for correct functioning of the cochlea as well as normal development and function of the vestibule.

  14. CT-scanning of the temporal bone in an inner ear malformation

    Energy Technology Data Exchange (ETDEWEB)

    Murata, K.; Hosoi, H.; Isono, M.; Ohta, F. (Kinki Univ., Higashi-Osaka, Osaka (Japan))

    1982-05-01

    CT-scanning of the temporal bone revealed a fine contour of the inner ear anomaly in a 8-year-old boy with total deafness on the right. In the inner ear there was a globular mass with a small protrusion anteriorly and with a probably immature superior semi-circular canal. The globular mass was considered to be the utriculosaccular capsule, and the anterior protrusion to be an incipient cochlear duct. CT-scanning of the temporal bone may bring significant progress in diagnosis of inner ear anomalies. Detailed configuration of an inner ear may be shown before histological examination.

  15. Human acoustics: From vocal chords to inner ear

    Science.gov (United States)

    Lamar, Michael Drew

    2005-11-01

    Part I covers the vocal chords, more accurately known as the vocal folds (VF). Modeling efforts are split into two areas: the VF tissue and the airflow. There are multiple existing models of the VF, with varying ranges of complexity for both the tissue and the airflow. In our model, the tissue is based on a recent two-mass model of Bogaert's [5], while the airflow is quasi-one-dimensional and is derived from the two-dimensional compressible Navier-Stokes equations. Our model is more accurate than Bernoulli's law (quasi-steady approximation), yet less complex than the full Navier-Stokes system. The model is shown to reproduce important transient behaviour intrinsic in vocal fold motion, such as pressure peaks before and after vocal fold closure. Part II concerns the inner ear, or cochlea. Again the modeling effort is split into two areas: the cochlear tissue and the cochlear fluid. We model the cochlear fluid with the well known two-dimensional box model of the cochlea, derived from the three-dimensional compressible Navier-Stokes equations. The cochlear tissue structure is where the complexity takes place. We start with Neely and Kim's [25] linear active model for the cochlear structure and modify their active gain parameter into a nonlinear nonlocal functional. The nonlinearity forces us to work in the time domain, which is prone to dispersive instabilities if one uses a frequency domain middle ear model. The middle ear's role as a transient absorber is discussed and its time domain formulation is shown to reduce the dispersive instability. We perform simulations on the full system and show that the model recovers many important nonlinear phenomena, such as suppression and difference tones. A spectrogram based on the cochlear response is created and compared with the spectrogram of the input waveform. In both Part I and Part II, the emphasis is on time dependent modeling and numerical implementation.

  16. Novel in vivo imaging analysis of an inner ear drug delivery system: Drug availability in inner ear following different dose of systemic drug injections.

    Science.gov (United States)

    Kanzaki, Sho; Watanabe, Kotaro; Fujioka, Masato; Shibata, Shinsuke; Nakamura, Masaya; Okano, Hirotaka James; Okano, Hideyuki; Ogawa, Kaoru

    2015-12-01

    Systemic application of drugs is commonly used in clinical situations. Some of these drugs are ototoxic. Since there are few studies on in vivo monitoring of drug delivery dynamics, the time course or bioavailability of drugs in the inner ear of live animals following systemic drug application remains unknown. For instance, it is unknown whether the volume of a drug delivered systemically correlates with its inner ear pharmacokinetics. We previously established a new in vivo imaging system to monitor drug delivery in live mice. In the present study, we used this system to compare drug concentration in the inner ear over time after systemic drug injections. We used transgenic GFAP-Luc mice that harbor a firefly luciferase gene expression cassette regulated by 12 kb of murine GFAP promoter and human beta-globin intron 2. Luciferin delivered into the inner ear of these mice reacts with luciferase, and the resulting signals are detected in GFAP-expressing cells in the cochlear nerve. Thus, we assessed in the inner ear the intensity and duration of luciferin/luciferase signals after systemic injections of different volumes of luciferin. An IVIS(®) imaging system was used to observe signals, and these signals were compared to the drug dynamics of luciferin delivered through subcutaneous (sc) injections. The volume of sc-injected drug correlated significantly with photon counts measured in the inner ear. Photons were detected almost immediately after injection, peaking 20 min after injection. Drug concentration did not affect inner ear signals. Luciferin injected systemically appeared in the inner ear between highest and lowest concentration. Drug volume is an important parameter to know if the inner ear requires a higher level of the drug. We observed that it is the volume of a drug-not its concentration-that is the important factor. Indeed, the more volume of a drug injected systemically increased the concentration of that drug in the inner ear. This study provides a

  17. Monitoring inner ear pressure changes in normal guinea pigs induced by the Meniett (R) 20

    NARCIS (Netherlands)

    Feijen, RA; Segenhout, JM; Wit, HP; Albers, FWJ

    2000-01-01

    The inner ear fluid pressure of guinea pigs was measured during a series of complex escalating middle ear pressure changes induced by the Meniett(R)20 (Pascal Medical, Sweden), a possible therapeutic pressure generator to be used by patients with Meniere's disease. Middle ear pressure changes were t

  18. Monitoring inner ear pressure changes in normal guinea pigs induced by the Meniett (R) 20

    NARCIS (Netherlands)

    Feijen, RA; Segenhout, JM; Wit, HP; Albers, FWJ

    2000-01-01

    The inner ear fluid pressure of guinea pigs was measured during a series of complex escalating middle ear pressure changes induced by the Meniett(R)20 (Pascal Medical, Sweden), a possible therapeutic pressure generator to be used by patients with Meniere's disease. Middle ear pressure changes were

  19. Neurofilament localization and phosphorylation in the developing inner ear of the rat.

    NARCIS (Netherlands)

    Tonnaer, E.L.G.M.; Peters, T.A.; Curfs, J.H.A.J.

    2010-01-01

    Detailed understanding of neurofilament protein distribution in the inner ear can shed light on regulatory mechanisms involved in neuronal development of this tissue. We assessed the spatio-temporal changes in the distribution of neurofilaments in the developing rat inner ear between embryonic day

  20. [Clinical features of sudden sensorineural hearing loss accompanied with inner ear hemorrhage].

    Science.gov (United States)

    Chen, Xihang; Lin, Chang; Fang, Zheming; Chen, Xi; Ye, Shengnan; Cheng, Jinmei; Zhang, Rong

    2015-12-01

    To investigate the clinical features, diagnosis and prognosis of sudden sensorineural hearing loss accompanied with inner ear hemorrhage. Eleven cases of sudden sensorineural hearing loss accompanied with inner ear hemorrhage were retrospectively analyzed, including clinical manifestation, hematological and audiological examinations, as well as characteristics of inner ear three-dimensional fluid-attenuated inversion recovery magnetic resonance imaging (3D-FLAIR MRI). Eleven cases of sudden hearing loss with inner ear hemorrhage were accompanied by varying degrees of vertigo, lasting from several minutes to several hours, nine of whom had persistent tinnitus. The audiometry curves of the 11 cases included total deafness or flat descending type. The inner ear 3D-FLAIR MRI studies revealed abnormal high signals at different positions of the inner ear, one case with endolymphatic hydrops. After the treatment, seven cases were invalid, two cases had notable effect, and two cases were effective. Abnormal high signals in the inner ear were sensitively detected by 3D-FLAIR MRI sequence, which was applied for the diagnosis of the sudden hearing loss accompanied with inner ear hemorrhage. The effect of conventional treatment was not good and the appropriate treatments for this type of sudden hearing loss need further investigation.

  1. Immune system of the inner ear as a novel therapeutic target for sensorineural hearing loss

    Directory of Open Access Journals (Sweden)

    Takayuki eOkano

    2014-09-01

    Full Text Available Sensorineural hearing loss (SNHL is a common clinical condition resulting from dysfunction in one or more parts in the auditory pathway between the inner ear and auditory cortex. Despite the prevalence of SNHL, little is known about its etiopathology, although several mechanisms have been postulated including ischemia, viral infection or reactivation, and microtrauma. Immune-mediated inner ear disease has been introduced and accepted as one SNHL pathophysiology; it responds to immunosuppressive therapy and is one of the few reversible forms of bilateral SNHL. The concept of immune-mediated inner ear disease is straightforward and comprehensible, but criteria for clinical diagnosis and the precise mechanism of hearing loss have not been determined. Moreover, the therapeutic mechanisms of corticosteroids are unclear, leading to several misconceptions by both clinicians and investigators concerning corticosteroid therapy. This review addresses our current understanding of the immune system in the inner ear and its involvement in the pathophysiology in SNHL. Treatment of SNHL, including immune-mediated inner ear disorder, will be discussed with a focus on the immune mechanism and immunocompetent cells as therapeutic targets. Finally, possible interventions modulating the immune system in the inner ear to repair the tissue organization and improve hearing in patients with SNHL will be discussed. Tissue macrophages in the inner ear appear to be a potential target for modulating the immune response in the inner ear in the pathophysiology of SNHL.

  2. Inner ear morphology in the Atlantic molly Poecilia mexicana--first detailed microanatomical study of the inner ear of a cyprinodontiform species.

    Directory of Open Access Journals (Sweden)

    Tanja Schulz-Mirbach

    Full Text Available BACKGROUND: Fishes show an amazing diversity in hearing abilities, inner ear structures, and otolith morphology. Inner ear morphology, however, has not yet been investigated in detail in any member of the diverse order Cyprinodontiformes. We, therefore, studied the inner ear of the cyprinodontiform freshwater fish Poecilia mexicana by analyzing the position of otoliths in situ, investigating the 3D structure of sensory epithelia, and examining the orientation patterns of ciliary bundles of the sensory hair cells, while combining μ-CT analyses, scanning electron microscopy, and immunocytochemical methods. P. mexicana occurs in different ecotypes, enabling us to study the intra-specific variability (on a qualitative basis of fish from regular surface streams, and the Cueva del Azufre, a sulfidic cave in southern Mexico. RESULTS: The inner ear of Poecilia mexicana displays a combination of several remarkable features. The utricle is connected rostrally instead of dorso-rostrally to the saccule, and the macula sacculi, therefore, is very close to the utricle. Moreover, the macula sacculi possesses dorsal and ventral bulges. The two studied ecotypes of P. mexicana showed variation mainly in the shape and curvature of the macula lagenae, in the curvature of the macula sacculi, and in the thickness of the otolithic membrane. CONCLUSIONS: Our study for the first time provides detailed insights into the auditory periphery of a cyprinodontiform inner ear and thus serves a basis--especially with regard to the application of 3D techniques--for further research on structure-function relationships of inner ears within the species-rich order Cyprinodontiformes. We suggest that other poeciliid taxa, or even other non-poeciliid cyprinodontiforms, may display similar inner ear morphologies as described here.

  3. Cochlear aqueduct flow resistance is not constant during evoked inner ear pressure change in the guinea pig

    NARCIS (Netherlands)

    Wit, HP; Feijen, RA; Albers, FWJ

    Inner ear fluid pressure was measured during 6.25 mHz square wave middle ear pressure manipulation, with a perforated tympanic membrane. After a negative-going middle ear pressure change the calculated flow resistance of the inner ear pressure release routes (mainly the cochlear aqueduct) was

  4. Cochlear aqueduct flow resistance is not constant during evoked inner ear pressure change in the guinea pig

    NARCIS (Netherlands)

    Wit, HP; Feijen, RA; Albers, FWJ

    2003-01-01

    Inner ear fluid pressure was measured during 6.25 mHz square wave middle ear pressure manipulation, with a perforated tympanic membrane. After a negative-going middle ear pressure change the calculated flow resistance of the inner ear pressure release routes (mainly the cochlear aqueduct) was approx

  5. Characteristics of laser-induced shock wave injury to the inner ear of rats

    Science.gov (United States)

    Kurioka, Takaomi; Matsunobu, Takeshi; Niwa, Katsuki; Tamura, Atsushi; Kawauchi, Satoko; Satoh, Yasushi; Sato, Shunichi; Shiotani, Akihiro

    2014-12-01

    Recently, the number of blast injuries of the inner ear has increased in the general population. In blast-induced inner ear injury, a shock wave (SW) component in the blast wave is considered to play an important role in sensorineural hearing loss. However, the mechanisms by which an SW affects inner ear tissue remain largely unknown. We aimed to establish a new animal model for SW-induced inner ear injury by using laser-induced SWs (LISWs) on rats. The LISWs were generated by irradiating an elastic laser target with 694-nm nanosecond pulses of a ruby laser. After LISW application to the cochlea through bone conduction, auditory measurements revealed the presence of inner ear dysfunction, the extent of which depended on LISW overpressure. A significantly lower survival rate of hair cells and spiral ganglion neurons, as well as severe oxidative damage, were observed in the inner ear exposed to an LISW. Although considerable differences in the pressure characteristics exist between LISWs and SWs in real blast waves, the functional and morphological changes shown by the present LISW-based model were similar to those observed in real blast-induced injury. Thus, our animal model is expected to be useful for laboratory-based research of blast-induced inner ear injury.

  6. Novel in vivo imaging analysis of an inner ear drug delivery system in mice: comparison of inner ear drug concentrations over time after transtympanic and systemic injections.

    Directory of Open Access Journals (Sweden)

    Sho Kanzaki

    Full Text Available OBJECTIVE: Systemic steroid injections are used to treat idiopathic sudden-onset sensorineural hearing loss (ISSHL and some inner ear disorders. Recent studies show that transtympanic (TT steroid injections are effective for treating ISSHL. As in vivo monitoring of drug delivery dynamics for inner ear is lacking, its time course and dispersion of drugs is unknown. Here, we used a new in vivo imaging system to monitor drug delivery in live mice and to compare drug concentrations over time after TT and systemic injections. METHODS: Luciferin delivered into the inner ears of GFAP-Luc transgenic mice reacted with luciferase in GFAP-expressing cells in the cochlear spiral ganglion, resulting in photon bioluminescence. We used the Xenogen IVIS® imaging system to measure how long photons continued to be emitted in the inner ear after TT or systemic injections of luciferin, and then compared the associated drug dynamics. RESULTS: The response to TT and IP injections differed significantly. Photons were detected five minutes after TT injection, peaking at ~20 minutes. By contrast, photons were first detected 30 minutes after i.p. injection. TT and i.p. drug delivery time differed considerably. With TT injections, photons were detected earlier than with IP injections. Photon bioluminescence also disappeared sooner. Delivery time varied with TT injections. CONCLUSIONS: We speculate that the drug might enter the Eustachian tube from the middle ear. We conclude that inner-ear drug concentration can be maintained longer if the two injection routes are combined. As the size of luciferin differs from that of therapeutics like dexamethasone, combining drugs with luciferin may advance our understanding of in vivo drug delivery dynamics in the inner ear.

  7. Anatomical and physiological development of the human inner ear.

    Science.gov (United States)

    Lim, Rebecca; Brichta, Alan M

    2016-08-01

    We describe the development of the human inner ear with the invagination of the otic vesicle at 4 weeks gestation (WG), the growth of the semicircular canals from 5 WG, and the elongation and coiling of the cochlea at 10 WG. As the membranous labyrinth takes shape, there is a concomitant development of the sensory neuroepithelia and their associated structures within. This review details the growth and differentiation of the vestibular and auditory neuroepithelia, including synaptogenesis, the expression of stereocilia and kinocilia, and innervation of hair cells by afferent and efferent nerve fibres. Along with development of essential sensory structures we outline the formation of crucial accessory structures of the vestibular system - the cupula and otolithic membrane and otoconia as well as the three cochlea compartments and the tectorial membrane. Recent molecular studies have elaborated on classical anatomical studies to characterize the development of prosensory and sensory regions of the fetal human cochlea using the transcription factors, PAX2, MAF-B, SOX2, and SOX9. Further advances are being made with recent physiological studies that are beginning to describe when hair cells become functionally active during human gestation. This article is part of a Special Issue entitled Reviews 2016>.

  8. The fluid mechanics of the inner-ear disorder BPPV

    Science.gov (United States)

    Weidman, Michael; Squires, Todd; Stone, Howard

    2001-11-01

    The inner ear of mammals contains fluid-filled semi-circular canals with a flexible sensory membrane (called a cupula) which detects rotational acceleration. Benign Paroxysmal Positional Vertigo (BPPV) is one of the most common disorders of this system diagnosed today, and is characterized by symptoms of dizziness and nausea brought on by sudden changes in head orientation. BPPV is believed to have a mechanical (rather than nervous) origin, in which dense particles called otoconia settle into the canals and trigger false sensations of rotational acceleration. Several qualitative mechanisms have been proposed by the medical community, which we examine from a fluid mechanical standpoint. Traditionally, the semicircular canal and the cupula are modeled as an over-damped torsional pendulum with a driving force provided by rotational acceleration. We extend this model to include the time-dependent mechanical response owing to sedimentation of the otoconia. We make qualitative and quantitative predictions associated with the proposed mechanisms, with an eye towards differentiating between them and perhaps towards more effective diagnostic and therapeutic methods.

  9. Extraintestinal Crohn's disease mimicking autoimmune inner ear disease: a histopathological approach.

    Science.gov (United States)

    Dettmer, M; Hegemann, I; Hegemann, S C A

    2011-01-01

    Patients with autoimmune inner ear disease develop rapidly progressive sensorineural hearing loss over a period of several weeks or months, often accompanied by vestibular loss. This disease can occur as a distinct clinical entity or in association with an underlying autoimmune disorder. Treatment comprises immunosuppression by corticosteroids, cytostatic drugs or tumor necrosis factor-α antagonists. We report histopathological and immunohistochemical findings of the inner ear of a patient with a granulomatous inner ear disease suffering from Crohn's disease that was nonresponsive to treatment and who underwent surgery for bilateral cochlear implants.

  10. Effects of NSAIDs on the Inner Ear: Possible Involvement in Cochlear Protection

    Directory of Open Access Journals (Sweden)

    Akira Hara

    2010-04-01

    Full Text Available Cyclooxygenase and lipoxygenase, two important enzymes involved in arachidonic acid metabolism, are major targets of non-steroidal anti-inflammatory drugs (NSAIDs. Recent investigations suggest that arachidonic cascades and their metabolites may be involved in maintaining inner ear functions. The excessive use of aspirin may cause tinnitus in humans and impairment of the outer hair cell functions in experimental animals. On the other hand, NSAIDs reportedly exhibit protective effects against various kinds of inner ear disorder. The present review summarizes the effects of NSAIDs on cochlear pathophysiology. NSAIDs are a useful ameliorative adjunct in the management of inner ear disorders.

  11. Signaling regulating inner ear development: cell fate determination, patterning, morphogenesis, and defects.

    Science.gov (United States)

    Nakajima, Yuji

    2015-02-01

    The membranous labyrinth of the inner ear is a highly complex organ that detects sound and balance. Developmental defects in the inner ear cause congenital hearing loss and balance disorders. The membranous labyrinth consists of three semicircular ducts, the utricle, saccule, and endolymphatic ducts, and the cochlear duct. These complex structures develop from the simple otic placode, which is established in the cranial ectoderm adjacent to the neural crest at the level of the hindbrain at the early neurula stage. During development, the otic placode invaginates to form the otic vesicle, which subsequently gives rise to neurons for the vestibulocochlear ganglion, the non-sensory and sensory epithelia of the membranous labyrinth that includes three ampullary crests, two maculae, and the organ of Corti. Combined paracrine and autocrine signals including fibroblast growth factor, Wnt, retinoic acid, hedgehog, and bone morphogenetic protein regulate fate determination, axis formation, and morphogenesis in the developing inner ear. Juxtacrine signals mediated by Notch pathways play a role in establishing the sensory epithelium, which consists of mechanosensory hair cells and supporting cells. The highly differentiated organ of Corti, which consists of uniformly oriented inner/outer hair cells and specific supporting cells, develops during fetal development. Developmental alterations/arrest causes congenital malformations in the inner ear in a spatiotemporal-restricted manner. A clearer understanding of the mechanisms underlying inner ear development is important not only for the management of patients with congenital inner ear malformations, but also for the development of regenerative therapy for impaired function.

  12. Kinetics of reciprocating drug delivery to the inner ear.

    Science.gov (United States)

    Pararas, Erin E Leary; Chen, Zhiqiang; Fiering, Jason; Mescher, Mark J; Kim, Ernest S; McKenna, Michael J; Kujawa, Sharon G; Borenstein, Jeffrey T; Sewell, William F

    2011-06-10

    Reciprocating drug delivery is a means of delivering soluble drugs directly to closed fluid spaces in the body via a single cannula without an accompanying fluid volume change. It is ideally suited for drug delivery into small, sensitive and unique fluid spaces such as the cochlea. We characterized the pharmacokinetics of reciprocating drug delivery to the scala tympani within the cochlea by measuring the effects of changes in flow parameters on the distribution of drug throughout the length of the cochlea. Distribution was assessed by monitoring the effects of DNQX, a reversible glutamate receptor blocker, delivered directly to the inner ear of guinea pigs using reciprocating flow profiles. We then modeled the effects of those parameters on distribution using both an iterative curve-fitting approach and a computational fluid dynamic model. Our findings are consistent with the hypothesis that reciprocating delivery distributes the drug into a volume in the base of the cochlea, and suggest that the primary determinant of distribution throughout more distal regions of the cochlea is diffusion. Increases in flow rate distributed the drug into a larger volume that extended more apically. Over short time courses (less than 2h), the apical extension, though small, significantly enhanced apically directed delivery of drug. Over longer time courses (>5h) or greater distances (>3mm), maintenance of drug concentration in the basal scala tympani may prove more advantageous for extending apical delivery than increases in flow rate. These observations demonstrate that this reciprocating technology is capable of providing controlled delivery kinetics to the closed fluid space in the cochlea, and may be suitable for other applications such as localized brain and retinal delivery.

  13. Erythropoietin and erythropoietin receptor expression in the guinea pig inner ear

    DEFF Research Database (Denmark)

    Cayé-Thomasen, Per; Wagner, Niels; Lidegaard Frederiksen, Birgitte

    2005-01-01

    The erythropoietin receptor (EPOR) is expressed in the brain and erythropoietin (EPO) has been shown to have neurotrophic and neuroprotective functions in the central nervous system and in the retina. These findings may be applied to the inner ear, pending EPO receptor presence. Accordingly......, this study determines expression of EPO and EPOR in the inner ear of the guinea pig. Normal guinea pig inner ears were processed for immunohistochemistry, using poly-clonal antibodies against EPO and the EPO receptor. EPO expression was exclusively found in most, but not all spiral ganglion neurons...... expressed by several cell types within the guinea pig cochlea. We hypothesize on the existence of a local paracrine system and that EPO treatment may be feasible following inner ear damage....

  14. Modelling of the Human Inner Ear Anatomy and Variability for Cochlear Implant Applications

    DEFF Research Database (Denmark)

    Kjer, Hans Martin

    several challenges concerning data processing and analysis. Our approach is to describe the inner ear as a statistical shape model. The thesis covers our work with regards to data segmentation, shape characterization, development of image registration model suited for the inner ear and construction......This thesis takes the biomedical engineering approach to working with and understanding the anatomy and physiology of the inner ear. The purpose is to apply the acquired knowledge in the development of implantable hearing aids. The so-called Cochlear Implant (CI) is a fascinating technology...... of statistical deformation models. The thesis results in a series of applications relating to CIs. The shape model can be used by CI-manufacturers for virtual product development and testing. At the same time, it can be applied to estimate the detailed inner ear shape from a clinical patient CT scan. This opens...

  15. Inner ear anomalies seen on CT images in people with Down syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Intrapiromkul, Jarunee; Aygun, Nafi; Yousem, David M. [The Johns Hopkins Medical Institutions, The Russell H. Morgan Department of Radiology and Radiological Sciences, Baltimore, MD (United States); Tunkel, David E. [The Johns Hopkins Medical Institutions, Department of Otolaryngology-Head and Neck Surgery, Baltimore, MD (United States); Carone, Marco [University of California, Division of Biostatistics, School of Public Health, Berkeley, CA (United States)

    2012-12-15

    Although dysplasia of inner ear structures in Down syndrome has been reported in several histopathological studies, the imaging findings have not been widely studied. To evaluate the prevalence and clinical significance of inner ear anomalies detected on CT images in patients with Down syndrome. The temporal bone CT images of patients with Down syndrome were assessed for inner ear anomalies; clinical notes and audiograms were reviewed for hearing loss. Logistic regression models were employed to identify which CT findings were associated with sensorineural hearing loss (SNHL). Inner ear anomalies were observed in 74.5% (38/51) of patients. Malformed bone islands of lateral semicircular canal (LSCC), narrow internal auditory canals (IACs), cochlear nerve canal stenoses, semicircular canal dehiscence (SCCD), and enlarged vestibular aqueducts were detected in 52.5% (53/101), 24.5% (25/102), 21.4% (21/98), 8.8% (9/102) and 2% (2/101) of patients' ears, respectively. IAC stenosis had the highest odds ratio (OR = 5.37, 95% CI: 1.0-28.9, P = 0.05) for SNHL. Inner ear anomalies occurred in 74.5% of our population, with malformed (<3 mm) bone island of LSCC being the most common (52.5%) anomaly. Narrow IAC was seen in 24.5% of patients with Down syndrome and in 57.1% of ears with SNHL. High-resolution CT is a valuable for assessing the cause of hearing loss in people with Down syndrome. (orig.)

  16. The progenitors of inner ear hair cells and their regulating genes

    Institute of Scientific and Technical Information of China (English)

    SHU Wei-ning; ZHAO Li-dong; ZHANG Xiao-bing; YANG Shi-ming

    2010-01-01

    @@ Hair cells in the mammalian inner ear are very fragile and are often injured as a result of acoustic trauma or exposure to ototoxic drugs (cisplatin, aminoglycosides, etc)[1]. In amphibians and birds, spontaneous post-injury regeneration of all inner ear sensory hair cell occurs, while in the mammalian cochlea, such hearing loss is usually permanent as there are currently no treatments that can lead to post-injury hair cell regeneration.

  17. BMP4 Signaling is Involved in the Generation of Inner Ear Sensory Epithelia

    OpenAIRE

    Wang Yucheng; Zhao Yanling; Wang Zhengmin; Corrales Carleton E; Li Huawei; Liu Hong; Heller Stefan

    2005-01-01

    Abstract Background The robust expression of BMP4 in the incipient sensory organs of the inner ear suggests possible roles for this signaling protein during induction and development of auditory and vestibular sensory epithelia. Homozygous BMP4-/- animals die before the inner ear's sensory organs develop, which precludes determining the role of BMP4 in these organs with simple gene knockout experiments. Results Here we use a chicken otocyst culture system to perform quantitative studies on th...

  18. Middle and inner ear malformations in two cases of velocardiofacial syndrome

    OpenAIRE

    Tabith Junior,Alfredo; Haetinger, Rainer Guilherme; Silva,Fernando Leite de Carvalho e; Gudmon, Monica de Castro

    2009-01-01

    Objective: To describe audiometric characteristics and middle and inner ear malformations in two patients with velocardiofacial syndrome. Method: Audiometric evaluation, computerized tomography of the temporal bones and analysis of DNA for multiple markers of 22q11 region were performed in two patients with clinical signs of velocardiofacial syndrome. Results: Conductive hearing loss related to chronic otites media and middle and inner ear malformations were found, the latter with the use of ...

  19. Malformations of the middle and inner ear on CT imaging in 22q11 deletion syndrome.

    Science.gov (United States)

    Loos, Elke; Verhaert, Nicolas; Willaert, Annelore; Devriendt, Koenraad; Swillen, Ann; Hermans, Robert; Op de Beeck, Katya; Hens, Greet

    2016-11-01

    The 22q11 deletion syndrome (22q11DS), the most frequent microdeletion syndrome in humans, presents with a large variety of abnormalities. A common abnormality is hearing impairment. The exact pathophysiological explanation of the observed hearing loss remains largely unknown. The aim of this study was to analyze the middle and inner ear malformations as seen on computer tomographic imaging in patients with 22q11DS. We retrospectively reviewed the charts of 11 22q11DS patients who had undergone a CT of the temporal bone in the past. Of the 22 examined ears, two showed an abnormal malleus and incus, 10 presented with a dense stapes superstructure, and three ears had an abnormal orientation of the stapes. With regard to the inner ear, 12 ears showed an incomplete partition type II with a normal vestibular aqueduct. In four ears the vestibule and lateral semicircular canal were composed of a single cavity, in 14 ears the vestibule was too wide, and three ears had a broadened lateral semicircular canal. These findings suggest that malformations of the stapes, cochlea, vestibule, and lateral semicircular canal are frequent in 22q11DS. To our knowledge, the current study involves the largest case series describing middle and inner ear malformations in 22q11DS. © 2016 Wiley Periodicals, Inc.

  20. miR-124 promotes the neuronal differentiation of mouse inner ear neural stem cells

    Science.gov (United States)

    Jiang, Di; Du, Jintao; Zhang, Xuemei; Zhou, Wei; Zong, Lin; Dong, Chang; Chen, Kaitian; Chen, Yu; Chen, Xihui; Jiang, Hongyan

    2016-01-01

    MicroRNAs (miRNAs or miRs) act as key regulators in neuronal development, synaptic morphogenesis and plasticity. However, their role in the neuronal differentiation of inner ear neural stem cells (NSCs) remains unclear. In this study, 6 miRNAs were selected and their expression patterns during the neuronal differentiation of inner ear NSCs were examined by RT-qPCR. We demonstrated that the culture of spiral ganglion stem cells present in the inner ears of newborn mice gave rise to neurons in vitro. The expression patterns of miR-124, miR-132, miR-134, miR-20a, miR-17-5p and miR-30a-5p were examined during a 14-day neuronal differentiation period. We found that miR-124 promoted the neuronal differentiation of and neurite outgrowth in mouse inner ear NSCs, and that the changes in the expression of tropomyosin receptor kinase B (TrkB) and cell division control protein 42 homolog (Cdc42) during inner ear NSC differentiation were associated with miR-124 expression. Our findings indicate that miR-124 plays a role in the neuronal differentiation of inner ear NSCs. This finding may lead to the development of novel strategies for restoring hearing in neurodegenerative diseases.

  1. Adenovirus Vectors Target Several Cell Subtypes of Mammalian Inner Ear In Vivo

    Science.gov (United States)

    Li, Wenyan; Shen, Jun

    2016-01-01

    Mammalian inner ear harbors diverse cell types that are essential for hearing and balance. Adenovirus is one of the major vectors to deliver genes into the inner ear for functional studies and hair cell regeneration. To identify adenovirus vectors that target specific cell subtypes in the inner ear, we studied three adenovirus vectors, carrying a reporter gene encoding green fluorescent protein (GFP) from two vendors or with a genome editing gene Cre recombinase (Cre), by injection into postnatal days 0 (P0) and 4 (P4) mouse cochlea through scala media by cochleostomy in vivo. We found three adenovirus vectors transduced mouse inner ear cells with different specificities and expression levels, depending on the type of adenoviral vectors and the age of mice. The most frequently targeted region was the cochlear sensory epithelium, including auditory hair cells and supporting cells. Adenovirus with GFP transduced utricular supporting cells as well. This study shows that adenovirus vectors are capable of efficiently and specifically transducing different cell types in the mammalian inner ear and provides useful tools to study inner ear gene function and to evaluate gene therapy to treat hearing loss and vestibular dysfunction. PMID:28116172

  2. [Changes in plasma inner ear hormones after endolymphatic sac drainage and steroid-instillation surgery (EDSS)].

    Science.gov (United States)

    Kitahara, Tadashi; Horii, Arata; Mishiro, Yasuo; Fukushima, Munehisa; Kondoh, Kazumasa; Okumura, Shin-ichi; Takeda, Noriaki; Kubo, Takeshi

    2002-05-01

    We treated 33 cases of intractable Meniere's disease with endolymphatic sac drainage and steroid-instillation surgery (EDSS), attaining good long-term results in vertigo and hearing. To elucidate how EDSS affects the diseased inner ear, we examined changes in plasma inner ear hormones after EDSS. Among inner ear hormones, plasma vasopressin was significantly decreased after EDSS compared to after mastoidectomy. In cases with good long-term results in vertigo and hearing, postoperative plasma vasopressin remained lower over the long term than in cases with poor results. In cases with negative glycerol test results one year after surgery, postoperative plasma vasopressin also remained significantly lower over the long term than in cases with positive results. Previous studies reported that vestibular neurons projected into hypothalamic supraoptic and paraventricular nuclei and that changes in the inner ear pressure were related to plasma vasopressin. Taken together with present findings, this suggests that EDSS may reduce plasma vasopressin through modification of the diseased inner ear environment, resulting in improved inner ear function.

  3. The candidate splicing factor Sfswap regulates growth and patterning of inner ear sensory organs.

    Directory of Open Access Journals (Sweden)

    Yalda Moayedi

    2014-01-01

    Full Text Available The Notch signaling pathway is thought to regulate multiple stages of inner ear development. Mutations in the Notch signaling pathway cause disruptions in the number and arrangement of hair cells and supporting cells in sensory regions of the ear. In this study we identify an insertional mutation in the mouse Sfswap gene, a putative splicing factor, that results in mice with vestibular and cochlear defects that are consistent with disrupted Notch signaling. Homozygous Sfswap mutants display hyperactivity and circling behavior consistent with vestibular defects, and significantly impaired hearing. The cochlea of newborn Sfswap mutant mice shows a significant reduction in outer hair cells and supporting cells and ectopic inner hair cells. This phenotype most closely resembles that seen in hypomorphic alleles of the Notch ligand Jagged1 (Jag1. We show that Jag1; Sfswap compound mutants have inner ear defects that are more severe than expected from simple additive effects of the single mutants, indicating a genetic interaction between Sfswap and Jag1. In addition, expression of genes involved in Notch signaling in the inner ear are reduced in Sfswap mutants. There is increased interest in how splicing affects inner ear development and function. Our work is one of the first studies to suggest that a putative splicing factor has specific effects on Notch signaling pathway members and inner ear development.

  4. The candidate splicing factor Sfswap regulates growth and patterning of inner ear sensory organs.

    Science.gov (United States)

    Moayedi, Yalda; Basch, Martin L; Pacheco, Natasha L; Gao, Simon S; Wang, Rosalie; Harrison, Wilbur; Xiao, Ningna; Oghalai, John S; Overbeek, Paul A; Mardon, Graeme; Groves, Andrew K

    2014-01-01

    The Notch signaling pathway is thought to regulate multiple stages of inner ear development. Mutations in the Notch signaling pathway cause disruptions in the number and arrangement of hair cells and supporting cells in sensory regions of the ear. In this study we identify an insertional mutation in the mouse Sfswap gene, a putative splicing factor, that results in mice with vestibular and cochlear defects that are consistent with disrupted Notch signaling. Homozygous Sfswap mutants display hyperactivity and circling behavior consistent with vestibular defects, and significantly impaired hearing. The cochlea of newborn Sfswap mutant mice shows a significant reduction in outer hair cells and supporting cells and ectopic inner hair cells. This phenotype most closely resembles that seen in hypomorphic alleles of the Notch ligand Jagged1 (Jag1). We show that Jag1; Sfswap compound mutants have inner ear defects that are more severe than expected from simple additive effects of the single mutants, indicating a genetic interaction between Sfswap and Jag1. In addition, expression of genes involved in Notch signaling in the inner ear are reduced in Sfswap mutants. There is increased interest in how splicing affects inner ear development and function. Our work is one of the first studies to suggest that a putative splicing factor has specific effects on Notch signaling pathway members and inner ear development.

  5. Congenital inner ear malformation: three dimensional volume rendering image using MR CISS sequence

    Energy Technology Data Exchange (ETDEWEB)

    Song, Jong Woon; Lee, In Sook; Kim, Hak Jin; Goh, Eui Kyung; Kim, Lee Suk [College of Medicine, Pusan National Univ., Pusan (Korea, Republic of)

    2003-10-01

    To evaluate three-dimensional volume-rendering of congenital inner-ear malformations using the MR CISS(Constructive Interference in Steady State) sequence. MR CISS images of 30 inner ears of 15 patients (M:F=10.5; mean age, 6.5years) in whom inner-ear malformation was suspected were obtained using a superconducting Magnetom Vision System (Simens, Erlangen, Germany), with TR/TE/FA parameters of 12.25 ms/5.9 ms/70.deg.. The images obtained were processed by means of the volume rendering technique at an advanced workstation (Voxtol 3.0.0; GE Systems, advanced workstation, volume analysis). The cochlea and three semicircular canals were morphologically evaluated. Volume-rendered images of 25 inner ears of 13 patients demonstrated cochlear anomalies in the form of incomplete partition (n=18), hypoplasia (n=2), and severe hypoplasia (n=5). For the superior semicircular canal, findings were normal in 15 ears, though common crus aplasia (n=6), hypoplasia (n=4), aplasia (n=3), and a short and broad shape (n=2) were also observed. The posterior semicircular canal of 13 ears was normal, but common crus aplasia (n=6), a short and broad shape (n=5), aplasia (n=4), hypoplasia (n=3) were also identified. Twelve lateral semicircular canals, were normal, but other images depicted a short and broad shape (n=7), a dilated crus (n=5), a broad shape (n=4), and aplasia (n=2). In 14 patients the anomalies were bilateral, and in seven, the same anomalies affected both ears. Three-dimensional volume rendering images of the inner ear depicted various morphological abnormalities of the cochlea and semicircular canals. At that locations, anomalies were more complicated and varied than in the cochlea. Three-dimensional volume rendering imaging using the MR CISS technique provides anatomical information regarding the membranous labyrinth, and we consider this useful in the evaluation of congenital inner ear malformations.

  6. Enlarged vestibular aqueducts and other inner-ear abnormalities in patients with Down syndrome.

    Science.gov (United States)

    Clark, C M; Patel, H H; Kanekar, S G; Isildak, H

    2017-04-01

    Histopathological anomalies of inner-ear structures in individuals with Down syndrome have been well documented; however, few studies have examined the radiological features. A retrospective study was conducted of temporal bone computed tomography images in 38 individuals (75 ears) with Down syndrome to evaluate the prevalence of inner-ear abnormalities and assess vestibular aqueduct widths. Inner-ear anomalies were identified in 20 of the 38 individuals (52.6 per cent). Seven of the 75 temporal bones (9.3 per cent) were found to have higher than previously reported. A dilated internal auditory canal and vestibule were more common among the present study group, while prior studies have demonstrated internal auditory canal stenosis and decreased vestibule size. Down syndrome patients exhibit a high prevalence of dysplastic inner-ear features that confer substantial risk of sensorineural hearing loss. Computed tomography is a useful screening aid to detect inner-ear abnormalities, particularly enlarged vestibular aqueducts, which cause preventable sensorineural hearing loss in this population.

  7. CT and MR imaging of congenital abnormalities of the inner ear and internal auditory canal

    Energy Technology Data Exchange (ETDEWEB)

    Casselman, Jan W. E-mail: jan.casselman@pi.be; Offeciers, Erwin F.; Foer, Bert de; Govaerts, Paul; Kuhweide, Rudy; Somers, Thomas

    2001-11-01

    The embryology of the inner ear must be known as many of the inner ear malformations present as a result of the arrest during the various stages of embryology. These malformations are described in this 'embryologic' perspective and specific names for certain malformations are no longer used. Both CT and MR can be used to look at inner ear malformations but often both techniques are complementary. However, CT is preferred when associated middle- or external ear malformations must be excluded. Magnetic resonance is preferred when subtle changes in the membranous labyrinth or abnormalities of the nerves in the internal auditory canal must be visualised. The CT and MR technique must however be adapted as more and more subtle congenital malformations can only be seen when the right technique is used. The heavily T2-weighted gradient-echo or fast spin-echo MR techniques are mandatory if malformations of the inner ear must be excluded. The purpose of this paper is to describe the techniques used to study these patients and to give an overview of the most frequent and important congenital malformations which can be found in the inner ear and internal auditory canal/cerebellopontine angle.

  8. CT and MR imaging of congential abnormalities of the inner ear and internal auditory canal.

    Science.gov (United States)

    Casselman, J W; Offeciers, E F; De Foer, B; Govaerts, P; Kuhweide, R; Somers, T

    2001-11-01

    The embryology of the inner ear must be known as many of the inner ear malformations present as a result of the arrest during the various stages of embryology. These malformations are described in this "embryologic" perspective and specific names for certain malformations are no longer used. Both CT and MR can be used to look at inner ear malformations but often both techniques are complementary. However, CT is preferred when associated middle- or external ear malformations must be excluded. Magnetic resonance is preferred when subtle changes in the membranous labyrinth or abnormalities of the nerves in the internal auditory canal must be visualised. The CT and MR technique must however be adapted as more and more subtle congenital malformations can only be seen when the right technique is used. The heavily T2-weighted gradient-echo or fast spin-echo MR techniques are mandatory if malformations of the inner ear must be excluded. The purpose of this paper is to describe the techniques used to study these patients and to give an overview of the most frequent and important congenital malformations which can be found in the inner ear and internal auditory canal/cerebellopontine angle.

  9. Expression of macrophage migration inhibitory factor and CD74 in the inner ear and middle ear in lipopolysaccharide-induced otitis media.

    Science.gov (United States)

    Ishihara, Hisashi; Kariya, Shin; Okano, Mitsuhiro; Zhao, Pengfei; Maeda, Yukihide; Nishizaki, Kazunori

    2016-10-01

    Significant expression of macrophage migration inhibitory factor and its receptor (CD74) was observed in both the middle ear and inner ear in experimental otitis media in mice. Modulation of macrophage migration inhibitory factor and its signaling pathway might be useful in the management of inner ear inflammation due to otitis media. Inner ear dysfunction secondary to otitis media has been reported. However, the specific mechanisms involved are not clearly understood. The aim of this study is to investigate the expression of macrophage migration inhibitory factor and CD74 in the middle ear and inner ear in lipopolysaccharide-induced otitis media. BALB/c mice received a transtympanic injection of either lipopolysaccharide or phosphate-buffered saline (PBS). The mice were sacrificed 24 h after injection, and temporal bones were processed for polymerase chain reaction (PCR) analysis, histologic examination, and immunohistochemistry. PCR examination revealed that the lipopolysaccharide-injected mice showed a significant up-regulation of macrophage migration inhibitory factor in both the middle ear and inner ear as compared with the PBS-injected control mice. The immunohistochemical study showed positive reactions for macrophage migration inhibitory factor and CD74 in infiltrating inflammatory cells, middle ear mucosa, and inner ear in the lipopolysaccharide-injected mice.

  10. Not All Inner Ears are the Same: Otolith Matrix Proteins in the Inner Ear of Sub-Adult Cichlid Fish, Oreochromis Mossambicus, Reveal Insights Into the Biomineralization Process.

    Science.gov (United States)

    Weigele, Jochen; Franz-Odendaal, Tamara A; Hilbig, Reinhard

    2016-02-01

    The fish ear stones (otoliths) consist mainly of calcium carbonate and have lower amounts of a proteinous matrix. This matrix consists of macromolecules, which directly control the biomineralization process. We analyzed the composition of this proteinous matrix by mass spectrometry in a shotgun approach. For this purpose, an enhanced protein purification technique was developed that excludes any potential contamination of proteins from body fluids. Using this method we identified eight proteins in the inner ear of Oreochromis mossambicus. These include the common otolith matrix proteins (OMP-1, otolin-1, neuroserpin, SPARC and otoconin), and three proteins (alpha tectorin, otogelin and transferrin) not previously localized to the otoliths. Moreover, we were able to exclude the occurrence of two matrix proteins (starmaker and pre-cerebellin-like protein) known from other fish species. In further analyses, we show that the absence of the OMP starmaker corresponds to calcitic otoliths and that pre-cerebellin-like protein is not present at any stage during the development of the otoliths of the inner ear. This study shows O. mossambicus does not have all of the known otolith proteins indicating that the matrix proteins in the inner ear of fish are not the same across species. Further functional studies of the novel proteins we identified during otolith development are required.

  11. Sudden sensorineural hearing loss: Is there a connection with inner ear electrolytic disorders? A literature review.

    Science.gov (United States)

    Ciorba, Andrea; Corazzi, Virginia; Bianchini, Chiara; Aimoni, Claudia; Skarzynski, Henryk; Skarzynski, Piotr Henryk; Hatzopoulos, Stavros

    2016-12-01

    Electrolytic disorders of the inner ear represent a model that could be implicated in partially explaining the pathogenesis of sudden sensorineural hearing loss (SSNHL). Different types of electrolytes and different inner-ear loci are involved in cochlear homeostasis physiologically, to ensure the maintenance of an ion-balanced cochlear environment allowing a normal hair cell function. It has been hypothesized that a sudden loss of endocochlear potential, due to a rapid disruption of the inner ear fluid osmolality, could be responsible for a deterioration of the hearing function caused by damaged hair cells. The aim of this paper was to review the current literature and identify sources which might validate/fortify the hypothesis that inner ear electrolytic disorders have a role in the etiopathogenesis of SSNHL. The data in the literature underline the importance of ionic homeostasis in the inner ear, but they do not support a direct link between SSNHL and electrolyte disorders/imbalances. There is marginal evidence from otoacoustic emissions research that an indirect link might be present. © The Author(s) 2016.

  12. Growth Hormone Promotes Hair Cell Regeneration in the Zebrafish (Danio rerio) Inner Ear following Acoustic Trauma

    OpenAIRE

    Huifang Sun; Chia-Hui Lin; Smith, Michael E.

    2011-01-01

    BACKGROUND: Previous microarray analysis showed that growth hormone (GH) was significantly upregulated following acoustic trauma in the zebrafish (Danio rerio) ear suggesting that GH may play an important role in the process of auditory hair cell regeneration. Our objective was to examine the effects of exogenous and endogenous GH on zebrafish inner ear epithelia following acoustic trauma. METHODOLOGY/PRINCIPAL FINDINGS: We induced auditory hair cell damage by exposing zebrafish to acoustic o...

  13. The Notch ligand JAG1 is required for sensory progenitor development in the mammalian inner ear.

    Directory of Open Access Journals (Sweden)

    Amy E Kiernan

    2006-01-01

    Full Text Available In mammals, six separate sensory regions in the inner ear are essential for hearing and balance function. Each sensory region is made up of hair cells, which are the sensory cells, and their associated supporting cells, both arising from a common progenitor. Little is known about the molecular mechanisms that govern the development of these sensory organs. Notch signaling plays a pivotal role in the differentiation of hair cells and supporting cells by mediating lateral inhibition via the ligands Delta-like 1 and Jagged (JAG 2. However, another Notch ligand, JAG1, is expressed early in the sensory patches prior to cell differentiation, indicating that there may be an earlier role for Notch signaling in sensory development in the ear. Here, using conditional gene targeting, we show that the Jag1 gene is required for the normal development of all six sensory organs within the inner ear. Cristae are completely lacking in Jag1-conditional knockout (cko mutant inner ears, whereas the cochlea and utricle show partial sensory development. The saccular macula is present but malformed. Using SOX2 and p27kip1 as molecular markers of the prosensory domain, we show that JAG1 is initially expressed in all the prosensory regions of the ear, but becomes down-regulated in the nascent organ of Corti by embryonic day 14.5, when the cells exit the cell cycle and differentiate. We also show that both SOX2 and p27kip1 are down-regulated in Jag1-cko inner ears. Taken together, these data demonstrate that JAG1 is expressed early in the prosensory domains of both the cochlear and vestibular regions, and is required to maintain the normal expression levels of both SOX2 and p27kip1. These data demonstrate that JAG1-mediated Notch signaling is essential during early development for establishing the prosensory regions of the inner ear.

  14. Bacterial Invasion of the Inner Ear in Association With Pneumococcal Meningitis

    DEFF Research Database (Denmark)

    Møller, Martin Nue; Brandt, Christian; Østergaard, Christian

    2014-01-01

    OBJECTIVE: To examine the pathways of bacterial invasion and subsequent spreading in the inner ear during pneumococcal meningitis. STUDY DESIGN: A well-established adult rat model of Streptococcus pneumoniae meningitis was used. METHODS: Thirty rats were inoculated intrathecally with S. pneumoniae...... serotype 1, 3 or 9 V and received no additional treatment. The rats were sacrificed when reaching terminal illness or on Day 7 and then prepared for serial sectioning and PAS-Alcian blue staining for light microscopy. RESULTS: During the first few days after inoculation, bacteria invade the inner ear...... scala vestibuli of the basal turn of the cochlea, hematogenous spreading occurred to the spiral ligament and into the cochlear endolymph, subsequently to the vestibular endolymph. We found no evidence of alternative routes for bacterial invasion in the inner ear. Several internal barriers to bacterial...

  15. Epigenetic regulation in the inner ear and its potential roles in development, protection, and regeneration

    Directory of Open Access Journals (Sweden)

    Jian eZuo

    2015-01-01

    Full Text Available The burgeoning field of epigenetics is beginning to make a significant impact on our understanding of tissue development, maintenance, and function. Epigenetic mechanisms regulate the structure and activity of the genome in response to intracellular and environmental cues that direct cell-type specific gene networks. The inner ear is comprised of highly specialized cell types with identical genomes that originate from a single totipotent zygote. During inner ear development specific combinations of transcription factors and epigenetic modifiers must function in a coordinated manner to establish and maintain cellular identity. These epigenetic regulatory mechanisms contribute to the maintenance of distinct chromatin states and cell-type specific gene expression patterns. In this review, we highlight emerging paradigms for epigenetic modifications related to inner ear development, and how epigenetics may have a significant role in hearing loss, protection, and regeneration.

  16. Contribution of fetal MRI to the diagnosis of inner ear abnormalities: report of two cases

    Energy Technology Data Exchange (ETDEWEB)

    Tilea, Bogdana; Garel, Catherine; Elmaleh-Berges, Monique; Sebag, Guy [Hopital Robert Debre, Department of Paediatric Imaging, Paris (France); Menez, Francoise; Delezoide, Anne-Lise [Hopital Robert Debre, Department of Developmental Biology, Paris (France); Vuillard, Edith [Hopital Robert Debre, Department of Obstetrics and Gynaecology, Paris (France)

    2006-02-01

    We report two cases of fetal inner ear abnormalities diagnosed by MRI. Cerebral MRI was performed on two fetuses, at 32 and 30 weeks gestation, following US that demonstrated multiple malformations suggestive of CHARGE syndrome in one fetus and ventriculomegaly and poor visibility of the posterior fossa in the other. MRI revealed vestibular hypoplasia and agenesis of the semicircular canals in one fetus and cystic cochleas, partial vermian agenesis and an occipital meningocele in the second fetus. Both pregnancies were terminated and there was good correlation between fetal MRI, ex utero CT and fetopathological findings. The inner ears should be carefully examined when performing fetal cerebral MRI because abnormalities of the inner ear may be associated with cerebral anomalies. (orig.)

  17. [Inner Ear Hearing Loss Part II: Sudden Sensorineural Hearing Loss, Therapeutic Options].

    Science.gov (United States)

    Hesse, Gerhard

    2016-07-01

    The great majority of hearing disorders generates from pathologies in the inner ear, mainly the outer hair cells, as mentioned in the first part of this review. Very often, however, hearing loss appears suddenly and even without external causes like noise exposure. This sudden hearing loss is mostly unilateral, recovers very often spontaneously and should be treated, if persisting. Only in this acute stage there are therapeutic options available. If the inner ear hearing loss is chronic there is no curative therapy, an effective management of the hearing disorder is only possible through rehabilitation. This is due to the fact, that hair cells of all mammals, incl. humans, have no regenerative capacity and neither pharmaceutic agents nor other means can induce regeneration and recovery of hair cells. Even a gen-therapy is not available yet. In the second part of this review the main focus lies in sudden hearing loss and general therapeutic options for inner ear hearing loss.

  18. Diversity of Inner Ears in Fishes: Possible Contribution Towards Hearing Improvements and Evolutionary Considerations.

    Science.gov (United States)

    Schulz-Mirbach, Tanja; Ladich, Friedrich

    2016-01-01

    Fishes have evolved the largest diversity of inner ears among vertebrates. While G. Retzius introduced us to the diversity of the gross morphology of fish ears in the late nineteenth century, it was A. N. Popper who unraveled the large variety of the fine structure during the last four decades. Modifications of the basic inner ear structure-consisting of three semicircular canals and their sensory epithelia, the cristae and three otolithic end organs (utricle, saccule, lagena) including the maculae-mainly relate to the saccule and lagena and the respective sensory epithelia, the macula sacculi and macula lagenae. Despite the profound morphological knowledge of inner ears and the morphological variability, the functional significance of this diversity is still largely unknown. The aims of this review are therefore twofold. First it provides an update of the state of the art of inner ear diversity in bony fishes. Second it summarizes and discusses hypotheses on the evolution of this diversity as well as formulates open questions and promising approaches to tackle these issues.

  19. Imaging of congenital anomalies and acquired lesions of the inner ear.

    Science.gov (United States)

    Krombach, Gabriele A; Honnef, Dagmar; Westhofen, Martin; Di Martino, Ercole; Günther, Rolf W

    2008-02-01

    Imaging of the temporal bone is under continous developement. In the recent decades the technical advances of magnetic resonance imaging and computed tomography have contributed to improved imaging quality in assessment of the temporal bone. Dedicated imaging protocols have been developed and are routinely employed in most institutions. However, imaging interpretation remains challenging, since the temporal bone is an anatomically highly complex region and most diseases of the inner ear occur with low incidence, so that even radiologists experienced in the field may be confronted with such entities for the first time. The current review gives an overview about symptoms and imaging appearance of malformations and acquired lesion of the inner ear.

  20. Imaging of congenital anomalies and acquired lesions of the inner ear

    Energy Technology Data Exchange (ETDEWEB)

    Krombach, Gabriele A.; Honnef, Dagmar; Guenther, Rolf W. [RWTH Aachen University Hospital, Department of Diagnostic Radiology, Aachen (Germany); Westhofen, Martin [RWTH Aachen University Hospital, Department of Otorhinolaryngology and Head and Neck Surgery, Aachen (Germany); Di Martino, Ercole [DIAKO Hospital Bremen, Department of Otorhinolaryngology and Head and Neck Surgery, Bremen (Germany)

    2008-02-15

    Imaging of the temporal bone is under continous developement. In the recent decades the technical advances of magnetic resonance imaging and computed tomography have contributed to improved imaging quality in assessment of the temporal bone. Dedicated imaging protocols have been developed and are routinely employed in most institutions. However, imaging interpretation remains challenging, since the temporal bone is an anatomically highly complex region and most diseases of the inner ear occur with low incidence, so that even radiologists experienced in the field may be confronted with such entities for the first time. The current review gives an overview about symptoms and imaging appearance of malformations and acquired lesion of the inner ear. (orig.)

  1. Inner ear hair cell regeneration A look from the past to the future

    Institute of Scientific and Technical Information of China (English)

    Francisco Santaolalla; Carlos Salvador; Agustn Martnez; Jose Mara Snchez; Ana Snchez del Rey

    2013-01-01

    Most recent studies on regeneration of inner ear hair cel s focus on use of stem cel s, gene therapy and neurotrophic factors. Cochlear gene therapy has been successful y used in the treatment of neu-rosensory hearing loss. This suggests that cochlear hair cel regeneration is possible. The objective of this paper is to review research and clinical application of inner near hair cel regeneration.

  2. Effect of the middle ear reflex on sound transmission to the inner ear of rat.

    Science.gov (United States)

    Pilz, P K; Ostwald, J; Kreiter, A; Schnitzler, H U

    1997-03-01

    The effect of the acoustic middle ear reflex (MER) was quantified using electrodes chronically implanted in the middle ears of rats. Cochlear microphonics (CM) and middle ear muscle EMG were measured under light Ketamin anesthesia after stimulation with tone pulses of 5-20 kHz ranging between 75 and 120 dB SPL. With increasing intensity, the CM measured before the onset of the MER increased to a maximum amplitude and then decreased with higher SPLs. At 10 kHz this maximum was reached at 95 dB SPL, for other stimulus frequencies at higher SPLs. After a latency of 10-20 ms, CM to 10 kHz stimuli of 80-95 dB SPL were decreased by the attenuating action of the MER. The lowest threshold of the MER was also measured at 10 kHz (77 dB SPL in the mean). To stimuli greater than 100 dB SPL after a latency of 6-10 ms, the CM amplitude was increased. That this CM increase to intense stimuli is caused by the action of the MER was confirmed by control experiments such as cutting the tendons of the middle ear muscles. The CM decrease to stimuli below 100 dB SPL, as well as the increase to very intense stimuli, can be explained by sound attenuation caused by the MER, together with the nonlinear dependence of CM amplitude on stimulus level. The observed shift of the maxima of the CM input-output function by the MER to higher stimulus levels probably indicates an increase of the dynamic range of the ear.

  3. Correlative mRNA and protein expression of middle and inner ear inflammatory cytokines during mouse acute otitis media.

    Science.gov (United States)

    Trune, Dennis R; Kempton, Beth; Hausman, Frances A; Larrain, Barbara E; MacArthur, Carol J

    2015-08-01

    Although the inner ear has long been reported to be susceptible to middle ear disease, little is known of the inflammatory mechanisms that might cause permanent sensorineural hearing loss. Recent studies have shown inner ear tissues are capable of expressing inflammatory cytokines during otitis media. However, little quantitative information is available concerning cytokine gene expression in the inner ear and the protein products that result. Therefore, this study was conducted of mouse middle and inner ear during acute otitis media to measure the relationship between inflammatory cytokine genes and their protein products with quantitative RT-PCR and ELISA, respectively. Balb/c mice were inoculated transtympanically with heat-killed Haemophilus influenzae and middle and inner ear tissues collected for either quantitative RT-PCR microarrays or ELISA multiplex arrays. mRNA for several cytokine genes was significantly increased in both the middle and inner ear at 6 h. In the inner ear, these included MIP-2 (448 fold), IL-6 (126 fold), IL-1β (7.8 fold), IL-10 (10.7 fold), TNFα (1.8 fold), and IL-1α (1.5 fold). The 24 h samples showed a similar pattern of gene expression, although generally at lower levels. In parallel, the ELISA showed the related cytokines were present in the inner ear at concentrations higher by 2-122 fold higher at 18 h, declining slightly from there at 24 h. Immunohistochemistry with antibodies to a number of these cytokines demonstrated they occurred in greater amounts in the inner ear tissues. These findings demonstrate considerable inflammatory gene expression and gene products in the inner ear following acute otitis media. These higher cytokine levels suggest one potential mechanism for the permanent hearing loss seen in some cases of acute and chronic otitis media.

  4. Toxic inner ear lesion following otitis media with effusion: a comparative CT-study regarding the morphology of the inner ear.

    Science.gov (United States)

    Wilhelm, Thomas; Stelzer, Tim; Wiegand, Susanne; Güldner, Christian; Teymoortash, Afshin; Günzel, Thomas; Hagen, Rudolf

    2015-12-01

    Viral infections of the upper respiratory airways can lead to a delayed viral otitis media (VOM) caused by a diffusion of viruses/virus particles through the round window membrane and resulting in sensorineural hearing loss. The treatment of choice is immediate paracentesis, evacuation of all fluids from the middle ear cavity, and haemorrheological infusions. However, in some cases, persistent symptoms may be an indication for a surgical approach using mastoidectomy. In high-resolution computed tomography, an extended small-sized pneumatisation of the mastoid cells with complete shading was found in these non-responsive cases. Therefore, a direct means of inner ear affliction through weak parts of the labyrinthine bone may be hypothesised. Patients suffering from a toxic inner ear lesion (TIEL) following a common cold, treated over a 10-year period in a Tertiary Care Centre (N = 52, 57 ears), were identified and the morphological characteristics of the temporal bones of affected patients were examined by means of high-resolution computed tomography (hrCT). The findings were compared with a matched control group of 64 normal ears (CONT). Measurements included the grade of pneumatisation, distances within the temporal bones and Hounsfield units (HU) at defined anatomical structures. In the TIEL group, we found a small-sized pneumatisation in 79.4 % and a medium-sized pneumatisation in 10.9 %, thus differing from the CONT group and the literature data. Thickness of the bone wall of the lateral semicircular canal (LSC) and distances within the aditus ad antrum were significantly reduced in the TIEL group. HU's were markedly lower in the TIEL group at the precochlea, the LSC, and dorsolateral to the promentia of the LSC. There was a correlation between the HU's at the prominentia of the LSC and the hearing loss (p = 0.002). Persisting interosseous globuli, as described in 1897 by Paul Manasse, form an osseochondral network within the otic capsule and may be responsible

  5. Effect of acute inner ear pressure changes on low-level distortion product otoacoustic emissions in the guinea pig

    NARCIS (Netherlands)

    Valk, WL; Wit, HP; Albers, FWJ

    2004-01-01

    Objective - To determine a relation between acute inner ear pressure changes and cochlear function as measured by low-level 2f(1) - f(2) distortion product otoacoustic emissions (DPOAEs). Material and Methods - During and after a change in inner ear pressure induced by injection or aspiration of per

  6. Laboratory model of inner ear mechano-transduction

    Science.gov (United States)

    Mohammad, Ibrahim; Prodanovic, Srdjan; Laiacona, Danielle; Nam, Jong-Hoon; Kelley, Douglas

    2016-11-01

    A sound wave entering the mammalian ear displaces cochlear fluid, which in turn displaces hair-like organelles called stereocilia that act as acoustic sensors. Their incredible sensitivity is poorly understood, and probably depends on pre-amplification via fluid-structure interaction. In this talk, I will show how our lab uses a laboratory model to simulate this biological system to study the viscous coupling between the vibrating structures, cochlear fluid, and stereocilia. I will present measurements of modeled stereocilia gain and phase difference over a range of frequencies. Recent numerical simulations show that the sensor behaves as a high-pass filter with a gain plateau. However, our results show a peak in the gain. Further, I will show how the length of stereocilia affects gain. This project was supported by NIH NIDCD R01 DC014685.

  7. Inner-ear decompression sickness: 'hubble-bubble' without brain trouble?

    Science.gov (United States)

    Tremolizzo, Lucio; Malpieri, Massimo; Ferrarese, Carlo; Appollonio, Ildebrando

    2015-06-01

    Inner-ear decompression sickness (DCS) is an incompletely understood and increasingly recognized condition in compressed-air divers. Previous reports show a high association of inner-ear DCS with persistent foramen ovale (PFO), suggesting that a moderate-to-severe right-to-left shunt might represent a major predisposing factor, and more properly defining it as an event from arterial gas embolism (AGE). However, other conditions characterized by bubbles entering the arterial circulation, such as open-chamber cardiac surgery, do not produce inner-ear involvement, while sometimes damaging the brain extensively. Moreover, in other sites, such as the spinal cord, the prevailing mechanism for DCS is not AGE, but more likely local bubble formation with subsequent compression of venules and capillaries. Thus, AGE might be, more properly, a predisposing condition, neither sufficient, nor possibly even strictly necessary for inner-ear DCS. A 'two-hit hypothesis' has been proposed, implying a locally selective vulnerability of the inner ear to AGE. Modelled kinetics for gas removal are slower in the inner ear compared to the brain, leading to a supersaturated environment which allows bubbles to grow until they eventually obstruct the labyrinthine artery. Since this artery is relatively small, there is a low probability for a bubble to enter it; this might explain the disproportion between the high prevalence of PFO in the general population (25-30%) and the very low incidence of inner-ear DCS in compressed-air diving (approximately 0.005%). Furthermore, given that the labyrinthine artery usually originates either from the anterior inferior cerebellar artery, or directly from the basilar artery, shunting bubbles will more frequently swarm through the entire brain. In this case, however, the brain's much faster gas removal kinetics might allow for them to be reabsorbed without damaging brain tissue. In line with this scenario is the low probability (approx. 15%) of inner-ear

  8. Malfunction of the inner ear is the most frequent cause of dizziness

    DEFF Research Database (Denmark)

    Klokker, Mads; Vesterhauge, Søren

    2013-01-01

    Half of all dizziness patients suffer from a malfunction of the inner ear and benign paroxysmal positional vertigo causes 25-30% of these malfunctions. During the latest two decades new vestibular test equipment has been developed and has made it possible to refine the vestibular diagnoses...

  9. Comparison of three methods for isolation of nucleic acids from membranate inner ear tissue of rats

    Institute of Scientific and Technical Information of China (English)

    KONG Wei-jia; WANG Ying; WANG Qiong; HAN Yue-chen; HU Yu-juan

    2006-01-01

    Background Mitochondrial DNA mutations have been found in sensorineural deafness. The aim of this study was to compare three methods for extraction of nucleic acid from membranate inner ear tissue of rats.Methods Alkaline denaturation, a conventional phenol-chloroform method and Trizol reagent were respectively used to extract the slight nucleic acid from membranate inner ear tissue of rats. We assessed the amount and quality of nucleic acid using a UV-spectrometer and polymerase chain reaction (PCR).Results The yield and purity (OD260/OD280) of DNA from inner ear tissue using the phenol-chloroform method was the highest of the three methods. Mitochondrial DNA (mtDNA) fragment can be amplified by PCR from nucleic acid prepared by all methods, while no nuclear DNA (nDNA) fragment can be amplified by method of alkaline denaturation. Both nuclear and mitochondrial genescould be amplified by reverse transcriptional PCR from the RNA prepared by Trizol reagent.Conclusion Adequate amount and high-quality of mtDNA, nDNA and RNA were obtained from unilateral membranate inner ear tissue of rats. Method of alkaline denaturation could be chosen when mtDNA without nDNA was needed, while phenol-chloroform method was suitable for extracting total DNA (including nDNA and mtDNA); method with Trizol reagent was suitable for extracting total RNA and total DNA.

  10. Dynamics of inner ear pressure change caused by intracranial pressure manipulation in the guinea pig

    NARCIS (Netherlands)

    Thalen, EO; Wit, HP; Segenhout, JM; Albers, FWJ

    2001-01-01

    Previous studies have shown that pressure changes in the cerebrospinal fluid compartment are transmitted to the inner ear. The main route for pressure transfer is the cochlear aqueduct, about which little is known with regard to its dynamic properties. In the present study, sudden intracranial press

  11. Innate immune defense in the inner ear - mucines are expressed by the human endolymphatic sac

    DEFF Research Database (Denmark)

    Møller, Martin N; Kirkeby, Svend; Cayé-Thomasen, Per

    2017-01-01

    The human endolymphatic sac has been shown recently to have immunological capacities and has thus been proposed as the main entity protecting the inner ear from pathogen invasion, equivalent to mucosa-associated lymphoid tissue (MALT). Although the sac expresses molecules of the innate immune sys...

  12. Dynamics of inner ear pressure change caused by intracranial pressure manipulation in the guinea pig

    NARCIS (Netherlands)

    Thalen, EO; Wit, HP; Segenhout, JM; Albers, FWJ

    Previous studies have shown that pressure changes in the cerebrospinal fluid compartment are transmitted to the inner ear. The main route for pressure transfer is the cochlear aqueduct, about which little is known with regard to its dynamic properties. In the present study, sudden intracranial

  13. Influence of fossoriality on inner ear morphology: insights from caecilian amphibians.

    Science.gov (United States)

    Maddin, Hillary C; Sherratt, Emma

    2014-07-01

    It is widely accepted that a relationship exists between inner ear morphology and functional aspects of an animal's biology, such as locomotor behaviour. Animals that engage in agile and spatially complex behaviours possess semicircular canals that morphologically maximise sensitivity to correspondingly complex physical stimuli. Stemming from the prediction that fossorial tetrapods require a well-developed sense of spatial awareness, we investigate the hypothesis that fossoriality leads to inner ear morphology that is convergent with other spatially adept tetrapods. We apply morphometrics to otic capsule endocasts of 26 caecilian species to quantify aspects of inner ear shape, and compare these with a sample of frog and salamander species. Our results reveal caecilians (and also frogs) possess strongly curved canals, a feature in common with spatially adept species. However, significantly shorter canals in caecilians suggest reduced sensitivity, possibly associated with reduced reliance on vestibulo-ocular reflexes in this group of visually degenerate tetrapods. An elaboration of the sacculus of caecilians is interpreted as a unique adaptation among amphibians to increase sensitivity to substrate-borne vibrations transmitted through the head. This study represents the first quantitative analyses of inner ear morphology of limbless fossorial tetrapods, and identifies features within a new behavioural context that will contribute to our understanding of the biological consequences of physical stimuli on sensory function and associated morphological evolution.

  14. 3D semi-automatic segmentation of the cochlea and inner ear.

    Science.gov (United States)

    Xianfen, Diao; Siping, Chen; Changhong, Liang; Yuanmei, Wang

    2005-01-01

    Though interactive direct volume rendering produces meaningful images with high quality, it cannot display separate inner ear labyrinth or cochlea only by adjusting imaging parameters to suppress the surrounding structures. Novel semi-automatic segmentation methods were presented to extract the cochlea and inner ear from spiral CT images. The cochlea was separated from the medical image volume by applying the 3D narrow band level set segmentation algorithm with user interaction introduced to locate the initial contour and adjust the parameters. The inner ear was extracted with a similar semi-automatic segmentation method: manual segmentation was first applied to remove several closely interconnected regions in boundary by viewing image volume slice by slice, then the 3D narrow band level set segmentation algorithm was used to complete fine segmentation on image volume. Generating 3D models of cochlea and inner ear structures with such methods not only takes advantage of the combination of 2D images with 3D volume but also saves much time of post-processing. The segmented results were rendered with the Marching Cubes surface rendering method. The correlation of the point on the resultant surface to the three orthogonal sections that intersect at that point on the surface was built to evaluate the segmented object and display the spatial relations of the anatomical structures. The performance of the presented semi-automatic segmentation methods is tested using spiral CT images of the temporal bone.

  15. Mechanotransduction in mouse inner ear hair cells requires transmembrane channel-like genes

    NARCIS (Netherlands)

    Kawashima, Yoshiyuki; Geleoc, Gwenaelle S. G.; Kurima, Kiyoto; Labay, Valentina; Lelli, Andrea; Asai, Yukako; Makishima, Tomoko; Wu, Doris K.; Della Santina, Charles C.; Holt, Jeffrey R.; Griffith, Andrew J.

    2011-01-01

    Inner ear hair cells convert the mechanical stimuli of sound, gravity, and head movement into electrical signals. This mechanotransduction process is initiated by opening of cation channels near the tips of hair cell stereocilia. Since the identity of these ion channels is unknown, and mutations in

  16. [Intervention of spiral ligament fibrocytes in the metabolic regulation of the inner ear].

    Science.gov (United States)

    García Berrocal, José Ramón; Méndez-Benegassi, Iván; Martí, Cristina; Ramírez Camacho, Rafael

    2008-12-01

    Maintenance of the K(+) gradient between endolymph and perilymph is essential for normal hearing and depends primarily on the activity of the stria vascularis. Abundant Na-K-ATPase in marginal strial cells provides a pumping mechanism for preserving the K(+) level of the endolymph and consequently, the endocochlear potential. Fibrocytes in the lateral wall of the cochlea supply K(+) to the strial pump, via gap junctions, by recycling back into the stria the ions that efflux from the scala media during auditory transduction. The lateral wall of the cochlea encloses five types of fibrocytes, differentiated by their location, structural features and content of enzymes mediating or energizing ion transport. The disruption of the gap junction bonds by connexin mutations and other pathologies leads to an interruption of K(+) recirculation pathways. The expression of cochlin and otoraplin, proteins that participate in structural or regulatory functions in the inner ear, suggests more diversity and complexity of the mesenchymal tissues than envisioned previously. The presence of otospiralin, a novel protein found in fibrocytes of spiral limbus, spiral ligament and subepithelial regions of the vestibule, represent a critical finding since that protein has been shown to be essential for the survival of the hair cells and supporting cells of the inner ear. A more profound knowledge and understanding of the function of inner ear fibrocytes will provide a new and promising aetiopathogenic approach to the treatment of inner ear disorders.

  17. Damage and Repair in the Inner Ear: From Experimental Research to Clinical Aspects

    NARCIS (Netherlands)

    Bremer, H.G.

    2013-01-01

    In this thesis, fundamental research is performed on the sensory epithelia of the inner ear in guinea pigs and mice. The outcomes of these fundamental studies are discussed in relation to clinical vestibular research. Methods to efficiently, repeatedly and reproducibly damage the sensory epithelia o

  18. Current concepts of hair cell differentiation and planar cell polarity in inner ear sensory organs.

    Science.gov (United States)

    Sienknecht, Ulrike J

    2015-07-01

    Phylogenetically and ontogenetically, vertebrate development led to the generation of several inner ear sensory organs. During embryogenesis, cell fate specification determines whether each progenitor cell differentiates into a sensory hair cell or a supporting cell within the common sensory primordium. Finally, all sensory epithelia of the inner ear consist of a hair cell/supporting cell mosaic, albeit with anatomical differences depending on the sensory organ type. Hair cells develop a polarized bundle of stereovilli that is of functional importance for mechanotransduction. After initiating stereovillar development, hair cells align their bundles in a coordinated fashion, generating a characteristic hair cell orientation pattern, a process referred to as planar cell polarity (PCP). The pathway that controls PCP in the inner ear needs both to establish the development of a polarized morphology of the stereovillar bundle of the hair cell and to organize a systematic hair cell alignment. Because the hair cell orientation patterns of the various inner ear organs and vertebrate species differ fundamentally, it becomes apparent that in vertebrates, different aspects of PCP need to be independently controlled. In spite of important progress recently gained in the field of PCP research, we still need to identify the mechanisms (1) that initiate molecular asymmetries in cells, (2) that guide the transmission of polarity information from cell to cell, and (3) that consistently translate such polarity information into morphological asymmetries of hair cells.

  19. Wildervanck's syndrome with severe inner ear dysplasia and agenesis of the right internal carotid artery.

    Science.gov (United States)

    Hernando, Mónica; Urbasos, María; Amarillo, Viviana Elizabeth; Herrera, María Teresa; García-Peces, Victoria; Plaza, Guillermo

    2014-04-01

    We describe a case with Wildervanck syndrome (cervico-oculo-acoustic syndrome) comprising Klippel-Feil anomaly, retractio bulbi (Duane syndrome), and congenital sensorineural deafness. An 18-month male baby had a severe inner ear dysplasia, and MRI also showed a complex vascular carotid malformation associated.

  20. BMP4 signaling is involved in the generation of inner ear sensory epithelia

    Directory of Open Access Journals (Sweden)

    Wang Yucheng

    2005-08-01

    Full Text Available Abstract Background The robust expression of BMP4 in the incipient sensory organs of the inner ear suggests possible roles for this signaling protein during induction and development of auditory and vestibular sensory epithelia. Homozygous BMP4-/- animals die before the inner ear's sensory organs develop, which precludes determining the role of BMP4 in these organs with simple gene knockout experiments. Results Here we use a chicken otocyst culture system to perform quantitative studies on the development of inner ear cell types and show that hair cell and supporting cell generation is remarkably reduced when BMP signaling is blocked, either with its antagonist noggin or by using soluble BMP receptors. Conversely, we observed an increase in the number of hair cells when cultured otocysts were treated with exogenous BMP4. BMP4 treatment additionally prompted down-regulation of Pax-2 protein in proliferating sensory epithelial progenitors, leading to reduced progenitor cell proliferation. Conclusion Our results implicate BMP4 in two events during chicken inner ear sensory epithelium formation: first, in inducing the switch from proliferative sensory epithelium progenitors to differentiating epithelial cells and secondly, in promoting the differentiation of hair cells within the developing sensory epithelia.

  1. The assessment and management of inner ear barotrauma in divers and recommendations for returning to diving.

    Science.gov (United States)

    Elliott, Elizabeth J; Smart, David R

    2014-12-01

    Inner ear barotrauma (IEBt) constitutes a spectrum of pressure-related pathology in the inner ear, with antecedent middle ear barotrauma (MEBt) common. IEBt includes perilymph fistula, intralabyrinthine membrane tear, inner ear haemorrhage and other rarer pathologies. Following a literature search, the pathophysiology, diagnosis, and treatment of IEBt in divers and best-practice recommendations for returning to diving were reviewed. Sixty-nine papers/texts were identified and 54 accessed. Twenty-five case series (majority surgical) provided guidance on diagnostic pathways; nine solely reported divers. IEBt in divers may be difficult to distinguish from inner ear decompression sickness (IEDCS), and requires dive-risk stratification and careful interrogation regarding diving-related ear events, clinical assessment, pure tone audiometry, a fistula test and electronystagmography (ENG). Once diagnosed, conservative management is the recommended first line therapy for IEBt. Recompression does not appear to cause harm if the diagnosis (IEBt vs IEDCS) is doubtful (limited case data). Exploratory surgery is indicated for severe or persisting vestibular symptoms or hearing loss, deterioration of symptoms, or lack of improvement over 10 days indicating significant pathology. Steroids are used, but without high-level evidence. It may be possible for divers to return to subaquatic activity after stakeholder risk acceptance and informed consent, provided: (1) sensorineural hearing loss is stable and not severe; (2) there is no vestibular involvement (via ENG); (3) high-resolution computed tomography has excluded anatomical predilection to IEBt and (4) education on equalising techniques is provided. There is a need for a prospective data registry and controlled trials to better evaluate diagnostic and treatment algorithms.

  2. Effects of topical oxiconazole and boric acid in alcohol solutions to rat inner ears.

    Science.gov (United States)

    Özdemir, Süleyman; Tuncer, Ülkü; Tarkan, Özgür; Akar, Funda; Sürmelioğlu, Özgür

    2013-06-01

    The aim of this study is to evaluate the ototoxicity of topical oxiconazole and boric acid in alcohol solutions. Prospective controlled animal study. Research laboratory. Fifty adult Wistar albino rats were divided into 5 groups consisting of 10 animals each. The right tympanic membranes were perforated, and baseline and posttreatment distortion product otoacoustic emission (DPOAE) measurements were performed. The solutions were applied through the external ear canal to the middle ear twice a day for 14 days. The rats in group I and group II received 0.1 mL of oxiconazole-containing solution drops and 4% boric acid in alcohol solution drops, respectively. Group III received gentamicin solution (40 mg/mL) (ototoxic control), group IV received saline solution, and group V was followed without any medication. The baseline DPOAE results of the right ears of all animals tested were normal. Animals in groups I, II, IV, and V showed no statistically significant change in the DPOAE amplitudes. The rats in the gentamicin group showed a significant decrease. This study demonstrates that topically used oxiconazole and boric acid in alcohol solutions to the middle ear appear to be safe on the inner ear of rats. The safety of these drugs has not yet been confirmed in humans. Caution should be taken when prescribing these drugs, especially to patients who had tympanic membrane perforation. Ear drops should be chosen more carefully in an external ear infection for patients with tympanic membrane perforation to avoid ototoxicity.

  3. Image analysis of the inner ear with CT and MR imaging; Pre-operative assessment for cochlear implant surgery

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    Kumakawa, Kohzoh; Takeda, Hidehiko; Mutoh, Naoko; Miyakawa, Kohichi (Toranomon Hospital, Tokyo (Japan)); Yukawa, Kumiko; Funasaka, Sohtaro

    1992-06-01

    Recent progress in magnetic resonance imaging (MRI) has made it possible to obtain detailed images of the inner ear by delineating the lymphatic fluid within the labyrinth. We analyzed CT scans and MR imaging in 70 ears manifesting profound deafness owing to inner ear lesions and compared their detective ability for inner ear lesions. The following results were obtained. CT scan examination showed slight to extensive ossification of the labyrinth in six ears (9%), whereas MRI examination revealed low to absent signal intensity of the inner ear in nine ears (13%). Therefore, it was concluded that MRI is more sensitive in detecting abnormalities of the inner ear than CT scan. MRI provided useful information as to whether the cochlear turn is filled with lymphatic fluid or obstructed. This point was one of the greatest advantages of MRI over CT scan. Abnormal findings in either or both the CT scan and the MRI were detected in suppurative labyrinthitis occurring secondary to chronic otitis media, bacterial meningitis and in inner ear trauma. However, such abnormal findings were not detected in patients with idiopathic progressive sensorineural hearing loss, ototoxity or sudden deafness. These findings should be taken into consideration in pre-operative assessment of cochlear implant candidates. (author).

  4. Microtomography of the human middle and inner ear

    Science.gov (United States)

    Vogel, Uwe; Beckmann, Felix; Zahnert, Thomas; Bonse, Ulrich

    2002-01-01

    Synchrotron radiation and x-ray microtomography based on absorption contrast (performed at HASYLAB at DESY/Hamburg and BAM/Berlin) have been used for imaging of temporal bones and various internal components in situ at spatial resolution down to 7 micrometers with potential enhancement into the submicron range. Due to the volume imaging approach, several hidden structures (e.g., intra-ossicular channels) were revealed. Using several 3D-image processing techniques all data have been segmented into objects (e.g., bony ossicles, ligaments, fluids, air spaces) and subsequently transformed into vectorized data models. Because they are based on the original voxel resolution their content of vector primitives (e.g., polygons) is huge compared to recent models. Therefore they became polygon-reduced to fit into current computation limitations. So far individual data models of the entire hearing apparatus from tympanic membrane to cochlea out of intact specimen, including separate models of ossicles, ligaments and other components have been obtained, provided, in interchangeable data formats (e.g. vector-based: IGES, STL, VRML) and introduced into FEA for modeling of acousto-mechanic transfer characteristics of the middle ear. Their pseudo and real 3D- visualizations (rendering, autosteroscopic display, enlarged solid models) allow easy understanding of the anatomy and pathology of the human hearing organ and may support patient and student education in the field of otology and audiology.

  5. Some Remarks on Imaging of the Inner Ear: Options and Limitations.

    Science.gov (United States)

    Giesemann, A; Hofmann, E

    2015-10-01

    The temporal bone has a highly complex anatomical structure, in which the sensory organs of the cochlea and the vestibular system are contained within a small space together with the sound-conducting system of the middle ear. Detailed imaging is thus required in this anatomical area. There are a great many clinical aims for which the highest-possible spatial resolution is required. These include the localization of cerebrospinal fluid fistulas, the detection of malformations of the middle and inner ear and the vestibulocochlear nerve, an aberrant course of the facial nerve and anomalies of the arterial and venous structures, the confirmation of dehiscence of the semicircular canals and finally, the verification of endolymphatic hydrops in cases of Ménière's disease. However, the term 'high resolution' is very time dependent. Two milestones in this respect have been (in 1991) the 3D visualization of the inner ear by means of maximum-intensity projection (MIP) of a T2-weighted constructive interference in steady state (CISS) sequence of a 1.5-tesla magnetic resonance imaging (MRI) scanner (Tanioka et al., Radiology 178:141-144, 1991) and (in 1997) imaging of the vestibulocochlear nerve for the diagnosis of hypoplasia inside the internal auditory canal using the same sequence (Casselman et al., Radiology 202:773-781, 1997).The objective of this article is to highlight the options for, and the challenges of, contemporary imaging with regard to some clinical issues relating to the inner ear.

  6. Clinical Application of 3D-FIESTA Image in Patients with Unilateral Inner Ear Symptom.

    Science.gov (United States)

    Oh, Jae Ho; Chung, Jae Ho; Min, Hyun Jung; Cho, Seok Hyun; Park, Chul Won; Lee, Seung Hwan

    2013-12-01

    Unilateral auditory dysfunction such as tinnitus and hearing loss could be a warning sign of a retrocochlear lesion. Auditory brainstem response (ABR) and internal auditory canal magnetic resonance image (MRI) are suggested as novel diagnostic tools for retrocochlear lesions. However, the high cost of MRI and the low sensitivity of the ABR test could be an obstacle when assessing patients with unilateral ear symptoms. The purpose of this study was to introduce the clinical usefulness of three-dimensional fast imaging employing steady-state acquisition (3D-FIESTA) MRI in patients with unilateral ear symptoms. Two hundred and fifty-three patients with unilateral tinnitus or unilateral hearing loss who underwent 3D-FIESTA temporal bone MRI as a screening test were enrolled. We reviewed the abnormal findings in the 3D-FIESTA images and ear symptoms using the medical records. In patients with unilateral ear symptoms, 51.0% of the patients had tinnitus and 32.8% patients were assessed to have sudden sensory neural hearing loss. With 3D-FIESTA imaging, twelve patients were diagnosed with acoustic neuroma, four with enlarged vestibular aqueduct syndrome, and two with posterior inferior cerebellar artery aneurysm. Inner ear anomalies and vestibulocochlear nerve aplasia could be diagnosed with 3D-FIESTA imaging. 3D-FIESTA imaging is a highly sensitive method for the diagnosis of cochlear or retrocochlear lesions. 3D-FIESTA imaging is a useful screening tool for patients with unilateral ear symptoms.

  7. The role of MRI in suspected inner ear malformations; Stellenwert der MRT bei Verdacht auf Innenohrmissbildung

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    Koesling, S.; Juettemann, S.; Amaya, B. [Halle-Wittenberg Univ., Halle (Germany). Klinik fuer Diagnostische Radiologie; Rasinski, C.; Bloching, M. [Halle-Wittenberg Univ., Halle (Germany). Klinik fuer Hals-, Nasen-, Ohrenkrankheiten; Koenig, E. [Leipzig Univ. (Germany). Klinik fuer Hals-, Nasen-, Ohrenkrankheiten

    2003-12-01

    Purpose: This is a prospective analysis of the value of MRI in suspected inner ear malformations. Materials and Methods: In 50 patients (43 children and young adults, 7 adults) with suspected inner ear malformation MRI (1.5 T) was performed. In addition, 42 of these patients underwent CT. For the analysis of the inner ear structures, the constructive interference in steady state (CISS) sequence with 0.7 mm slice thickness was used. Functional tests revealed a sensorineural hearing loss or deafness in 82 temporal bones (TB) and a combined hearing loss in 4 TB. The hearing loss was unilateral in 14 patients. MRI and CT findings were compared. Results: Imaging findings were normal in 58 TB. The pathological findings included inner ear malformations (35 TB), inflammatory changes (4 TB), partial obliteration of labyrinth (2 TB) and congenital aural atresia (1 TB). An isolated absence of the cochlear nerve (1 TB) could only be found by MRI. In the remaining cases, an inner ear malformation was diagnosed by MRI and CT with the same confidence but MRI was superior in displaying the fine details. Conclusions: MRI will become the method of choice in the diagnosis of inner ear malformations. (orig.) [German] Ziel: Das Ziel der Arbeit bestand in einer prospektiven Analyse des Stellenwertes der MRT bei Verdacht auf eine Innenohrmissbildung. Material und Methodik: 50 Patienten (43 Kinder und Jugendliche, 7 Erwachsene) mit dringendem Verdacht auf eine Innenohrmissbildung erhielten eine MRT-Untersuchung (1,5 T), bei 42 dieser Patienten wurde auch eine CT durchgefuehrt. Bei der Beurteilung der Innenohrstrukturen kam die CISS-Sequenz mit einer Schichtdicke von 0,7 mm zur Anwendung. Durch Funktionstests wurde an 82 Schlaefenbeinen (SB) eine Innenohrhoerstoerung und an 4 SB eine kombinierte Hoerstoerung diagnostiziert. 14 Patienten hatten eine einseitige Hoerstoerung. MRT- und CT-Ergebnisse wurden verglichen. Ergebnisse: Einen bildgebenden Normalbefund wiesen 58 SB auf. Folgende

  8. CT and MR imaging of the inner ear and brain in children with congenital sensorineural hearing loss.

    Science.gov (United States)

    Joshi, Varsha M; Navlekar, Shantanu K; Kishore, G Ravi; Reddy, K Jitender; Kumar, E C Vinay

    2012-01-01

    Imaging plays an important role in the evaluation of congenital sensorineural hearing loss. In children who are candidates for cochlear implantation surgery, it provides vital preoperative information about the inner ear, the vestibulocochlear nerve, and the brain. High-resolution computed tomography (CT) and magnetic resonance (MR) imaging provide excellent delineation of the intricate anatomy of the inner ear: CT depicts the minute details of osseous structures, and MR imaging allows visualization of the fluid-filled spaces and the vestibulocochlear nerve. Together, these complementary modalities can aid decision making about the best management strategy by facilitating the identification and characterization of inner ear malformations and any associated neurologic abnormalities. It is important that the radiologist be familiar with the key imaging features when interpreting CT and MR images obtained in this patient group. A broad spectrum of inner ear malformations have been described and linked to developmental insults at different stages of embryogenesis, and various systems have been proposed for classifying them. In this article, these malformations are described by using classification systems used by otolaryngologists for ease of interpretation. The relevant normal anatomy and development of the inner ear are briefly surveyed, standard imaging protocols for studying the inner ear are reviewed, and the imaging appearances of frequently observed inner ear malformations are described and illustrated. The impact of the identification of these malformations and commonly associated brain abnormalities on clinical management and prognosis also is discussed.

  9. Metal casts showing the three-dimensional structure of the human inner ear were converted into jewelry.

    Science.gov (United States)

    Heywood, Peter

    2015-06-01

    This article describes a straightforward method for making metal casts of the human inner ear developed in 1937 by M. Wharton Young of Howard University College of Medicine. These casts were used to study anatomy, but there do not appear to be any published photographs of the casts. Inner ear casts converted into jewelry provide the only known images of this work. Later, Young studied the inner ear in living rhesus monkeys by injecting mercury into their membranous labyrinths. Young's investigations indicated a blind-ending perilymphatic sac that was not in continuity with the subarachnoid space.

  10. Middle and inner ear malformations in two cases of velocardiofacial syndrome

    Directory of Open Access Journals (Sweden)

    Tabith Junior, Alfredo

    2009-03-01

    Full Text Available Objective: To describe audiometric characteristics and middle and inner ear malformations in two patients with velocardiofacial syndrome. Method: Audiometric evaluation, computerized tomography of the temporal bones and analysis of DNA for multiple markers of 22q11 region were performed in two patients with clinical signs of velocardiofacial syndrome. Results: Conductive hearing loss related to chronic otites media and middle and inner ear malformations were found, the latter with the use of reformations based on multislice acquisitions on of the computerized tomography of the temporal bones. Conclusion: We consider it to be highly important to carry out a thorough evaluation and monitoring of the hearing evolution, as well as the occurrence of symptoms related to the vestibular function in patients with velocardiofacial syndrome. From the radiological point of view, attention should be given to the use of high quality techniques for the tomographic study of temporal bones.

  11. Basic and clinical physiology of the inner ear receptors and their neural pathways in the brain.

    Science.gov (United States)

    Sohmer, H; Freeman, S

    2000-01-01

    The six receptors of the inner ear (cochlea, two otolith organs and three semicircular canals) share a common transduction unit made up of a sensory hair cell, a first order sensory neuron and the synapse between them. Displacement of the stereocilia in a particular direction leads to excitation of the hair cell and activation of the neuron. Electrical and mechanical reflections of these stages of transduction can be recorded non-invasively in humans and in animals. These include cochlear microphonic potentials, otoacoustic emissions, auditory and vestibular evoked potentials. The ability to record these activities can be used to track the development of inner ear function in the fetus and neonate and to study the effects of various ototoxic agents (e.g. noise) and drugs.

  12. Neuronal feedback between brain and inner ear for growth of otoliths in fish

    Science.gov (United States)

    Anken, R. H.; Edelmann, E.; Rahmann, H.

    Previous investigations revealed that fish inner ear otolith growth (concerning otolith size and calcium-incorporation) depends on the amplitude and the direction of gravity, suggesting the existence of a (negative) feedback mechanism. In search for the regulating unit, the vestibular nerve was unilaterally transected in neonate swordtail fish ( Xiphophorus helleri) which were subsequently incubated in the calcium-tracer alizarin-complexone. Calcium incorporation ceased on the transected head sides, indicating that calcium uptake is neurally regulated.

  13. Expression patterns of members of the isocitrate dehydrogenase gene family in murine inner ear.

    Science.gov (United States)

    Kim, Y-R; Kim, K-H; Lee, S; Oh, S-K; Park, J-W; Lee, K-Y; Baek, J-I; Kim, U-K

    2017-09-19

    Age-related hearing loss (ARHL) is characterized by an age-dependent decline of auditory function characterized by with loss of sensory hair cells, spiral ganglion neurons, and stria vascularis (SV) cells in the cochlea of the inner ear. Aging and age-related diseases result from accumulated oxidative damage caused by reactive oxygen species (ROS) generated by mitochondria. The isocitrate dehydrogenase (IDH) family includes three enzymes in human cells: IDH1, IDH2, and IDH3. Although all three enzymes catalyze the same enzymatic reaction, that is, oxidative decarboxylation of isocitrate to produce α-ketoglutarate, each IDH enzyme has unique features. We identified and characterized IDH expression in the cochlea and vestibule of the murine inner ear. We examined the mRNA expression levels of Idh family members in the cochlea and vestibule using reverse transcription-PCR (RT-PCR) and detected expression of IDH family members in both tissues. We also used immunohistochemistry to localize IDH family members within the cochlea and vestibule of the adult mouse inner ear. IDH1 was detected throughout the cochlea. IDH2 was expressed specifically in the hair cells, spiral ganglion, and stria vascularis. IDH3α was found in the cell bodies of neurons of the spiral ganglion, the stria vascularis, and in types II, IV, and V cells of the spiral ligament in a pattern that resembled the location of the Na(+), K(+)-ATPase ion channel. We postulate that the IDH family participates in transporting K(+) ions in the cochlea. In the vestibule, all IDH family members were detected in both hair cells and the vestibular ganglion. We hypothesize that IDH1, IDH2, and IDH3 function to protect proteins in the inner ear from oxidative stress during K(+) recycling.

  14. Inner ear delivery of dexamethasone using injectable silk-polyethylene glycol (PEG) hydrogel.

    Science.gov (United States)

    Yu, Dehong; Sun, Changling; Zheng, Zhaozhu; Wang, Xueling; Chen, Dongye; Wu, Hao; Wang, Xiaoqin; Shi, Fuxin

    2016-04-30

    Minimally invasive delivery and sustained release of therapeutics to the inner ear are of importance to the medical treatment of inner ear disease. In this study, the injectable silk fibroin-polyethylene glycol (Silk-PEG) hydrogel was investigated as a drug delivery carrier to deliver poorly soluble micronized dexamethasone (mDEX) to the inner ear of guinea pigs. Encapsulation of mDEX with a loading up to 5% (w/v) did not significantly change the silk gelation time, and mDEX were evenly distributed in the PEG-Silk hydrogel as visualized by SEM. The loading of mDEX in Silk-PEG hydrogel largely influenced in vitro drug release kinetics. The optimized Silk-PEG-mDEX hydrogel (2.5% w/v loading, in situ-forming, 10 μl) was administered directly onto the round window membrane of guinea pigs. The DEX concentration in perilymph maintained above 100 ng/ml for at least 10 days for the Silk-PEG formulation while less than 12h for the control sample of free mDEX. Minimal systemic exposure was achieved with low DEX concentrations (Silk-PEG-mDEX hydrogel. A transient hearing threshold shift was found but then resolved after 14 days as revealed by auditory brainstem response (ABR), showing minimal inflammatory responses on the round window membrane and scala taympani. The Silk-PEG hydrogel completely degraded in 21 days. Thus, the injectable PEG-Silk hydrogel is an effective and safe vehicle for inner ear delivery and sustained release of glucocorticoid.

  15. Artificial induction of Sox21 regulates sensory cell formation in the embryonic chicken inner ear.

    Directory of Open Access Journals (Sweden)

    Stephen D Freeman

    Full Text Available During embryonic development, hair cells and support cells in the sensory epithelia of the inner ear derive from progenitors that express Sox2, a member of the SoxB1 family of transcription factors. Sox2 is essential for sensory specification, but high levels of Sox2 expression appear to inhibit hair cell differentiation, suggesting that factors regulating Sox2 activity could be critical for both processes. Antagonistic interactions between SoxB1 and SoxB2 factors are known to regulate cell differentiation in neural tissue, which led us to investigate the potential roles of the SoxB2 member Sox21 during chicken inner ear development. Sox21 is normally expressed by sensory progenitors within vestibular and auditory regions of the early embryonic chicken inner ear. At later stages, Sox21 is differentially expressed in the vestibular and auditory organs. Sox21 is restricted to the support cell layer of the auditory epithelium, while it is enriched in the hair cell layer of the vestibular organs. To test Sox21 function, we used two temporally distinct gain-of-function approaches. Sustained over-expression of Sox21 from early developmental stages prevented prosensory specification, and abolished the formation of both hair cells and support cells. However, later induction of Sox21 expression at the time of hair cell formation in organotypic cultures of vestibular epithelia inhibited endogenous Sox2 expression and Notch activity, and biased progenitor cells towards a hair cell fate. Interestingly, Sox21 did not promote hair cell differentiation in the immature auditory epithelium, which fits with the expression of endogenous Sox21 within mature support cells in this tissue. These results suggest that interactions among endogenous SoxB family transcription factors may regulate sensory cell formation in the inner ear, but in a context-dependent manner.

  16. [Investigation of neural stem cell-derived donor contribution in the inner ear following blastocyst injection].

    Science.gov (United States)

    Volkenstein, S; Brors, D; Hansen, S; Mlynski, R; Dinger, T C; Müller, A M; Dazert, S

    2008-03-01

    Utilising the enormous proliferation and multi-lineage differentiation potentials of somatic stem cells represents a possible therapeutical strategy for diseases of non-regenerative tissues like the inner ear. In the current study, the possibility of murine neural stem cells to contribute to the developing inner ear following blastocyst injection was investigated. Fetal brain-derived neural stem cells from the embryonic day 14 cortex of male mice were isolated and expanded for four weeks in neurobasal media supplemented with bFGF and EGF. Neural stem cells of male animals were harvested, injected into blastocysts and the blastocysts were transferred into pseudo-pregnant foster animals. Each blastocyst was injected with 5-15 microspheres growing from single cell suspension from neurospheres dissociated the day before. The resulting mice were investigated six months POST PARTUM for the presence of donor cells. Brainstem evoked response audiometry (BERA) was performed in six animals. To visualize donor cells Lac-Z staining was performed on sliced cochleas of two animals. In addition, the cochleas of four female animals were isolated and genomic DNA of the entire cochlea was analyzed for donor contribution by Y-chromosome-specific PCR. All animals had normal thresholds in brainstem evoked response audiometry. The male-specific PCR product indicating the presence of male donor cells were detected in the cochleas of three of the four female animals investigated. In two animals, male donor cells were detected unilateral, in one animal bilateral. The results suggest that descendants of neural stem cells are detectable in the inner ear after injection into blastocysts and possess the ability to integrate into the developing inner ear without obvious loss in hearing function.

  17. Congenital Malformations of the Inner Ear: Case Series and Review of the Literature.

    Science.gov (United States)

    Piromchai, Patorn; Kasemsiri, Pornthep; Thanawirattananit, Panida; Yimtae, Kwanchanok

    2015-08-01

    Patients with craniofacial anomalies often present to doctors due to their noticeable disfigurement and are routinely assessed by otolaryngologists for hearing evaluation. However, small percentage of craniofacial anomaly patients may present with delayed speech though they may not have initial obvious external deformation. The objective of case series is to identify the congenital inner ear malformation. The series of clinical presentation, physical examination, investigations, treatments and follow-up results were demonstrated followed by the discussion.

  18. Superior semicircular canal dehiscence associated with external, middle, and inner ear abnormalities.

    Science.gov (United States)

    Wang, Jenny R; Parnes, Lorne S

    2010-02-01

    We report a case of bilateral superior semicircular canal dehiscence (SSCD) in a 38-year-old man who presented with congenital hearing loss without vestibular symptoms. This case is unusual due to the association of SSCD with multiple congenital anomalies of the external, middle, and inner ears, but without any other craniofacial or systemic developmental anomalies. Findings of multiple malformations of temporal bone structures in this case lend support to the theory that SSCD may have an underlying developmental or congenital etiology.

  19. Zona pellucida domain-containing protein β-tectorin is crucial for zebrafish proper inner ear development.

    Directory of Open Access Journals (Sweden)

    Chung-Hsiang Yang

    Full Text Available BACKGROUND: The zona pellucida (ZP domain is part of many extracellular proteins with diverse functions from structural components to receptors. The mammalian β-tectorin is a protein of 336 amino acid residues containing a single ZP domain and a putative signal peptide at the N-terminus of the protein. It is 1 component of a gel-like structure called the tectorial membrane which is involved in transforming sound waves into neuronal signals and is important for normal auditory function. β-Tectorin is specifically expressed in the mammalian and avian inner ear. METHODOLOGY/PRINCIPAL FINDINGS: We identified and cloned the gene encoding zebrafish β-tectorin. Through whole-mount in situ hybridization, we demonstrated that β-tectorin messenger RNA was expressed in the otic placode and specialized sensory patch of the inner ear during zebrafish embryonic stages. Morpholino knockdown of zebrafish β-tectorin affected the position and number of otoliths in the ears of morphants. Finally, swimming behaviors of β-tectorin morphants were abnormal since the development of the inner ear was compromised. CONCLUSIONS/SIGNIFICANCE: Our results reveal that zebrafish β-tectorin is specifically expressed in the zebrafish inner ear, and is important for regulating the development of the zebrafish inner ear. Lack of zebrafish β-tectorin caused severe defects in inner ear formation of otoliths and function.

  20. A Review of Gene Delivery and Stem Cell Based Therapies for Regenerating Inner Ear Hair Cells

    Directory of Open Access Journals (Sweden)

    Michael S. Detamore

    2011-09-01

    Full Text Available Sensory neural hearing loss and vestibular dysfunction have become the most common forms of sensory defects, affecting millions of people worldwide. Developing effective therapies to restore hearing loss is challenging, owing to the limited regenerative capacity of the inner ear hair cells. With recent advances in understanding the developmental biology of mammalian and non-mammalian hair cells a variety of strategies have emerged to restore lost hair cells are being developed. Two predominant strategies have developed to restore hair cells: transfer of genes responsible for hair cell genesis and replacement of missing cells via transfer of stem cells. In this review article, we evaluate the use of several genes involved in hair cell regeneration, the advantages and disadvantages of the different viral vectors employed in inner ear gene delivery and the insights gained from the use of embryonic, adult and induced pluripotent stem cells in generating inner ear hair cells. Understanding the role of genes, vectors and stem cells in therapeutic strategies led us to explore potential solutions to overcome the limitations associated with their use in hair cell regeneration.

  1. BODIPY-Conjugated Xyloside Primes Fluorescent Glycosaminoglycans in the Inner Ear of Opsanus tau.

    Science.gov (United States)

    Holman, Holly A; Tran, Vy M; Kalita, Mausam; Nguyen, Lynn N; Arungundram, Sailaja; Kuberan, Balagurunathan; Rabbitt, Richard D

    2016-12-01

    We report on a new xyloside conjugated to BODIPY, BX and its utility to prime fluorescent glycosaminoglycans (BX-GAGs) within the inner ear in vivo. When BX is administered directly into the endolymphatic space of the oyster toadfish (Opsanus tau) inner ear, fluorescent BX-GAGs are primed and become visible in the sensory epithelia of the semicircular canals, utricle, and saccule. Confocal and 2-photon microscopy of vestibular organs fixed 4 h following BX treatment, reveal BX-GAGs constituting glycocalyces that envelop hair cell kinocilium, nerve fibers, and capillaries. In the presence of GAG-specific enzymes, the BX-GAG signals are diminished, suggesting that chondroitin sulfates are the primary GAGs primed by BX. Results are consistent with similar click-xylosides in CHO cell lines, where the xyloside enters the Golgi and preferentially initiates chondroitin sulfate B production. Introduction of BX produces a temporary block of hair cell mechanoelectrical transduction (MET) currents in the crista, reduction in background discharge rate of afferent neurons, and a reduction in sensitivity to physiological stimulation. A six-degree-of-freedom pharmacokinetic mathematical model has been applied to interpret the time course and spatial distribution of BX and BX-GAGs. Results demonstrate a new optical approach to study GAG biology in the inner ear, for tracking synthesis and localization in real time.

  2. Perspectives for the treatment of sensorineural hearing loss by cellular regeneration of the inner ear.

    Science.gov (United States)

    Almeida-Branco, Mario S; Cabrera, Sonia; Lopez-Escamez, Jose A

    2015-01-01

    Sensorineural hearing loss is a caused by the loss of the cochlear hair cells with the consequent deafferentation of spiral ganglion neurons. Humans do not show endogenous cellular regeneration in the inner ear and there is no exogenous therapy that allows the replacement of the damaged hair cells. Currently, treatment is based on the use of hearing aids and cochlear implants that present different outcomes, some difficulties in auditory discrimination and a limited useful life. More advanced technology is hindered by the functional capacity of the remaining spiral ganglion neurons. The latest advances with stem cell therapy and cellular reprogramming have developed several possibilities to induce endogenous regeneration or stem cell transplantation to replace damaged inner ear hair cells and restore hearing function. With further knowledge of the cellular and molecular biology of the inner ear and its embryonic development, it will be possible to use induced stem cells as in vitro models of disease and as replacement cellular therapy. Investigation in this area is focused on generating cellular therapy with clinical use for the treatment of profound sensorineural hearing loss. Copyright © 2014 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Patología Cérvico-Facial. All rights reserved.

  3. Applications for single cell trajectory analysis in inner ear development and regeneration.

    Science.gov (United States)

    Durruthy-Durruthy, Robert; Heller, Stefan

    2015-07-01

    Single cell trajectory analysis is a computational approach that orders cells along a pseudotime axis. This temporal modeling approach allows the characterization of transitional processes such as lineage development, response to insult, and tissue regeneration. The concept can also be applied to resolve spatial organization of cells within the originating tissue. Known as temporal and spatial transcriptomics, respectively, these methods belong to the most powerful analytical techniques for quantitative gene expression data currently available. Here, we discuss three different approaches: principal component analysis, the 'Monocle' algorithm, and self-organizing maps. We use a previously published qRT-PCR dataset of single neuroblast cells isolated from the developing mouse inner ear to highlight the basic features of the three methods and their individual limitations, as well as the distinct advantages that make them useful for research on the inner ear. The complex developmental morphogenesis of the inner ear and its specific challenges such as the paucity of cells as well as important open questions such as sensory hair cell regeneration render this organ a prime target for single cell trajectory analysis strategies.

  4. Auditory maturity and hearing performance in inner ear malformations: a histological and electrical stimulation approach.

    Science.gov (United States)

    Sainz, Manuel; Garcia-Valdecasas, Juan; Fernandez, Elena; Pascual, Maria Teresa; Roda, Olga

    2012-06-01

    The objective of this study was to assess the auditory performance of the neural structures in response to controlled electrical stimulation period. A prospective cohort study focused on the intracochlear electrical stimulation parameters and hearing performance of patients suffering different cochlear malformations who were treated by cochlear implants constituted the study design. The study sample constituted 16 patients, suffering profound prelingual hearing impairment, diagnosed on the basis of radiological criteria as having an inner ear malformation, and who underwent cochlear implantation and were followed for 24 months. Patients with common cavities, characterized by fewer nerve structures involved, less epithelial penetration, and deficient cochlear tonotopy distribution showed have higher thresholds and electrical charges than patients with cochlear hypoplasia, who in turn have higher thresholds than patients with minor malformations (p malformation and was also poor in patients with cochlear hypoplasia, who were unable to discriminate more than 50% of the words and relied on visual cues as a necessary aid to communication. Better results were reached by minor malformed inner ears. To conclude, the number of nerve structures involved, epithelial penetration and deficient cochlear tonotopy are responsible of inner ear functionality.

  5. Atrophic thyroid follicles and inner ear defects reminiscent of cochlear hypothyroidism in Slc26a4-related deafness.

    Science.gov (United States)

    Dror, Amiel A; Lenz, Danielle R; Shivatzki, Shaked; Cohen, Keren; Ashur-Fabian, Osnat; Avraham, Karen B

    2014-08-01

    Thyroid hormone is essential for inner ear development and is required for auditory system maturation. Human mutations in SLC26A4 lead to a syndromic form of deafness with enlargement of the thyroid gland (Pendred syndrome) and non-syndromic deafness (DFNB4). We describe mice with an Slc26a4 mutation, Slc26a4 (loop/loop) , which are profoundly deaf but show a normal sized thyroid gland, mimicking non-syndromic clinical signs. Histological analysis of the thyroid gland revealed defective morphology, with a majority of atrophic microfollicles, while measurable thyroid hormone in blood serum was within the normal range. Characterization of the inner ear showed a spectrum of morphological and molecular defects consistent with inner ear pathology, as seen in hypothyroidism or disrupted thyroid hormone action. The pathological inner ear hallmarks included thicker tectorial membrane with reduced β-tectorin protein expression, the absence of BK channel expression of inner hair cells, and reduced inner ear bone calcification. Our study demonstrates that deafness in Slc26a4 (loop/loop) mice correlates with thyroid pathology, postulating that sub-clinical thyroid morphological defects may be present in some DFNB4 individuals with a normal sized thyroid gland. We propose that insufficient availability of thyroid hormone during inner ear development plays an important role in the mechanism underlying deafness as a result of SLC26A4 mutations.

  6. Age-regulated function of autophagy in the mouse inner ear.

    Science.gov (United States)

    de Iriarte Rodríguez, Rocío; Pulido, Sara; Rodríguez-de la Rosa, Lourdes; Magariños, Marta; Varela-Nieto, Isabel

    2015-12-01

    Autophagy is a highly conserved catabolic process essential for embryonic development and adult homeostasis. The autophagic machinery supplies energy by recycling intracellular components and facilitates the removal of apoptotic cells. In the inner ear, autophagy has been reported to play roles during early development in the chicken embryo and in the response to otic injury in the adult mouse. However, there are no studies on the expression of the autophagy machinery in the postnatal and adult inner ear. Insulin-like growth factor 1 (IGF-1) is one of the factors that regulate both otic development and cochlear postnatal maturation and function. Here, we hypothesised that autophagy could be one of the processes involved in the cochlear development and functional maturation. We report that autophagy-related genes (ATG) Becn1, Atg4g and Atg5 are expressed in the mouse cochlea, vestibular system and brainstem cochlear nuclei from late developmental stages to adulthood. Atg9 was studied in the mouse cochlea and showed a similar pattern. The presence of autophagic flux was confirmed by decreased sequestosome 1 (SQSTM1/p62) and increased relative levels of microtubule-associated protein light chain 3-II (LC3-II). Inner ear autophagy flux is developmentally regulated and is lower at perinatal stages than in the adult mouse, where an expression plateau is reached at the age of two-months, coinciding with the age at which full functional activity is reached. Expression is maintained in adult mice and declines after the age of twelve months. LC3B labelling showed that autophagy was primarily associated with spiral ganglion neurons. Over time, Igf1 wild type mice showed lower expression of genes coding for IGF-1 high affinity receptor and the family factor IGF-2 than null mice. Parallel analysis of autophagy machinery gene expression showed no significant differences between the genotypes over the lifespan of the null mice. Taken together, these results show that the

  7. Gbx2 is required for the morphogenesis of the mouse inner ear: a downstream candidate of hindbrain signaling.

    Science.gov (United States)

    Lin, Zhengshi; Cantos, Raquel; Patente, Maria; Wu, Doris K

    2005-05-01

    Gbx2 is a homeobox-containing transcription factor that is related to unplugged in Drosophila. In mice, Gbx2 and Otx2 negatively regulate each other to establish the mid-hindbrain boundary in the neural tube. Here, we show that Gbx2 is required for the development of the mouse inner ear. Absence of the endolymphatic duct and swelling of the membranous labyrinth are common features in Gbx2-/- inner ears. More severe mutant phenotypes include absence of the anterior and posterior semicircular canals, and a malformed saccule and cochlear duct. However, formation of the lateral semicircular canal and its ampulla is usually unaffected. These inner ear phenotypes are remarkably similar to those reported in kreisler mice, which have inner ear defects attributed to defects in the hindbrain. Based on gene expression analyses, we propose that activation of Gbx2 expression within the inner ear is an important pathway whereby signals from the hindbrain regulate inner ear development. In addition, our results suggest that Gbx2 normally promotes dorsal fates such as the endolymphatic duct and semicircular canals by positively regulating genes such as Wnt2b and Dlx5. However, Gbx2 promotes ventral fates such as the saccule and cochlear duct, possibly by restricting Otx2 expression.

  8. Fates of mouse embryonic stem cells transplanted into the inner ears of adult mice and embryonic chickens.

    Science.gov (United States)

    Sakamoto, Tatsunori; Nakagawa, Takayuki; Endo, Tsuyoshi; Kim, Tae-Soo; Iguchi, Fukuichiro; Naito, Yasushi; Sasai, Yoshiki; Ito, Juichi

    2004-03-01

    The potential of embryonic stem (ES) cells to differentiate into inner ear hair cells was examined in this study. Undifferentiated mouse ES cells transplanted into neomycin-damaged mouse inner ears were evaluated by immunohistochemistry 4 weeks after transplantation. Some ES cells were positive for E-cadherin or NCAM, and most transplanted cells were positive for SSEA3 and Ki67. None were positive for Myosin VIIa or MF20. These results indicate that the damaged inner ear may have some activity inducing ES cells to develop into ectoderm cells, but the effect was insufficient to induce inner ear hair cells. Next, SDIA/BMP-treated ES cells were transplanted into embryonic chicken inner ear rudiments. Embryonic chickens were expected to share the same developmental systems as mice. SDIA/BMP treatment drove ES cells to the population including neural crest cells and probably placode cells ES colonies were found next to or in the otic vesicles but were not a part of vesicle walls, indicating that transplanted ES cells could not be expected to be the same kind of cells as chicken otic vesicle cells Some ES colonies were found at the vestibulo-cochlear ganglions. To induce inner ear hair cells in this system, the competency of ES cells and otic induction signals should be defined further.

  9. Recent advances in therapeutics and drug delivery for the treatment of inner ear diseases: a patent review (2011-2015).

    Science.gov (United States)

    Nguyen, Kim; Kempfle, Judith S; Jung, David H; McKenna, Charles E

    2017-02-01

    Inner ear disorders such as hearing loss, tinnitus, and Ménière's disease significantly impact the quality of life of affected individuals. Treatment of such disorders is an ongoing challenge. Current clinical approaches relieve symptoms but do not fully restore hearing, and the search for more effective therapeutic methods represents an area of urgent current interest. Areas covered: Thirty four patents and patent applications published from 2011 to 2015 were selected from the database of the U.S. Patent and Trademark Office (USPTO) and World Intellectual Property Organization (WIPO), covering new approaches for the treatment of inner ear disorders described in the patent literature: 1) identification of new therapeutic agents, 2) development of sustained release formulations, and 3) medical devices that facilitate delivery of such agents to the inner ear. Expert opinion: The search for effective treatments of inner ear disorders is ongoing. Increased understanding of the molecular mechanisms of hearing loss, Ménière's disease, and tinnitus is driving development of new therapeutic agents. However, delivery of these agents to the inner ear is a continuing challenge. At present, combination of a suitable drug with an appropriate mode of drug delivery is the key focus of innovative research to cure inner ear disorders.

  10. In vivo imaging of middle-ear and inner-ear microstructures of a mouse guided by SD-OCT combined with a surgical microscope

    Science.gov (United States)

    Cho, Nam Hyun; Jang, Jeong Hun; Jung, Woonggyu; Kim, Jeehyun

    2014-01-01

    We developed an augmented-reality system that combines optical coherence tomography (OCT) with a surgical microscope. By sharing the common optical path in the microscope and OCT, we could simultaneously acquire OCT and microscope views. The system was tested to identify the middle-ear and inner-ear microstructures of a mouse. Considering the probability of clinical application including otorhinolaryngology, diseases such as middle-ear effusion were visualized using in vivo mouse and OCT images simultaneously acquired through the eyepiece of the surgical microscope during surgical manipulation using the proposed system. This system is expected to realize a new practical area of OCT application. PMID:24787787

  11. Radioprotective Effect of Aminothiol PrC-210 on Irradiated Inner Ear of Guinea Pig.

    Directory of Open Access Journals (Sweden)

    Arnaud P J Giese

    Full Text Available Radiotherapy of individuals suffering with head & neck or brain tumors subserve the risk of sensorineural hearing loss. Here, we evaluated the protective effect of Aminothiol PrC-210 (3-(methyl-amino-2-((methylaminomethylpropane-1-thiol on the irradiated inner ear of guinea pigs. An intra-peritoneal or intra-tympanic dose of PrC-210 was administered prior to receiving a dose of gamma radiation (3000 cGy to each ear. Auditory Brainstem Responses (ABRs were recorded one week and two weeks after the radiation and compared with the sham animal group. ABR thresholds of guinea pigs that received an intra-peritoneal dose of PrC-210 were significantly better compared to the non-treated, control animals at one week post-radiation. Morphologic analysis of the inner ear revealed significant inflammation and degeneration of the spiral ganglion in the irradiated animals not treated with PrC-210. In contrast, when treated with PrC-210 the radiation effect and injury to the spiral ganglion was significantly alleviated. PrC-210 had no apparent cytotoxic effect in vivo and did not affect the morphology or count of cochlear hair cells. These findings suggest that aminothiol PrC-210 attenuated radiation-induced cochlea damage for at least one week and protected hearing.

  12. Cochlear implantation in patients with inner ear bone malformations with posterior labyrinth involvement: an exploratory study.

    Science.gov (United States)

    Palomeque Vera, Juan Miguel; Platero Sánchez-Escribano, María; Gómez Hervás, Javier; Fernández Prada, María; González Ramírez, Amanda Rocío; Sainz Quevedo, Manuel

    2016-04-01

    Inner ear bone malformations are one cause of profound sensorineural hearing loss. This investigation focused on those affecting the posterior labyrinth, especially enlarged vestibular aqueduct syndrome, which is associated with fluctuating and progressive hearing loss. The objectives of this study were to analyze the behavior of the electrical stimulation, auditory functionality and linguistic development in patients with inner ear malformations involving the posterior labyrinth. The study included ten patients undergoing cochlear implantation (cases: five with enlarged vestibular aqueduct, two with vestibular aqueduct stenosis/aplasia, and three with semicircular canal disorders). Post-implantation, data were gathered on the electrical stimulation threshold and maximum comfort levels and on the number of functioning electrodes. Evaluation of Auditory Responses to Speech (EARS) subtests were used to assess auditory functionality and language acquisition at 6, 12, and 24 months post-implantation. Results were compared with findings in a control group of 28 cochlear implantation patients without these malformations. No significant differences were found between case and control groups in electrical stimulation parameters; auditory functionality subtest scores were lower in cases than controls, although the difference was only statistically significant for some subtests. In conclusion, cochlear implantation patients with posterior labyrinth bone malformations and profound hearing loss, including those with enlarged vestibular aqueduct syndrome, showed no significant difference in electrical stimulation threshold with controls. Although some auditory functionality test results were lower in cases than in controls, cochlear implantation appears to be beneficial for all patients with these malformations.

  13. Inner-ear sound pressures near the base of the cochlea in chinchilla: Further investigation

    Science.gov (United States)

    Ravicz, Michael E.; Rosowski, John J.

    2013-01-01

    The middle-ear pressure gain GMEP, the ratio of sound pressure in the cochlear vestibule PV to sound pressure at the tympanic membrane PTM, is a descriptor of middle-ear sound transfer and the cochlear input for a given stimulus in the ear canal. GMEP and the cochlear partition differential pressure near the cochlear base ΔPCP, which determines the stimulus for cochlear partition motion and has been linked to hearing ability, were computed from simultaneous measurements of PV, PTM, and the sound pressure in scala tympani near the round window PST in chinchilla. GMEP magnitude was approximately 30 dB between 0.1 and 10 kHz and decreased sharply above 20 kHz, which is not consistent with an ideal transformer or a lossless transmission line. The GMEP phase was consistent with a roughly 50-μs delay between PV and PTM. GMEP was little affected by the inner-ear modifications necessary to measure PST. GMEP is a good predictor of ΔPCP at low and moderate frequencies where PV ⪢ PST but overestimates ΔPCP above a few kilohertz where PV ≈ PST. The ratio of PST to PV provides insight into the distribution of sound pressure within the cochlear scalae. PMID:23556590

  14. MicroRNA-183 Family in Inner Ear: Hair Cell Development and Deafness.

    Science.gov (United States)

    Mahmoodian Sani, Mohammad Reza; Hashemzadeh-Chaleshtori, Morteza; Saidijam, Massoud; Jami, Mohammad-Saeid; Ghasemi-Dehkordi, Payam

    2016-12-01

    miRNAs are essential factors of an extensively conserved post-transcriptional process controlling gene expression at mRNA level. Varoius biological processes such as growth and differentiation are regulated by miRNAs. Web of Science and PubMed databases were searched using the Endnote software for the publications about the role miRNA-183 family in inner ear: hair cell development and deafness published from 2000 to 2016. A triplet of these miRNAs particularly the miR-183 family is highly expressed in vertebrate hair cells, as with some of the peripheral neurosensory cells. Point mutations in one member of this family, miR-96, underlie DFNA50 autosomal deafness in humans and lead to abnormal hair cell development and survival in mice. In zebrafish, overexpression of the miR-183 family induces extra and ectopic hair cells, while knockdown decreases the number of hair cell. The miR-183 family (miR-183, miR-96 and miR-182) is expressed abundantly in some types of sensory cell in the eye, nose and inner ear. In the inner ear, mechanosensory hair cells have a robust expression level. Despite much similarity of these miRs sequences, small differences lead to distinct targeting of messenger RNAs targets. In the near future, miRNAs are likely to be explored as potential therapeutic agents to repair or regenerate hair cells, cell reprogramming and regenerative medicine applications in animal models because they can simultaneously down-regulate dozens or even hundreds of transcripts.

  15. Cubilin and megalin co-localize in the neonatal inner ear.

    Science.gov (United States)

    Tauris, Jacob; Christensen, Erik Ilsø; Nykjaer, Anders; Jacobsen, Christian; Petersen, Claus Munck; Ovesen, Therese

    2009-01-01

    Cubilin and megalin are multifunctional endocytotic receptors expressed in many absorptive epithelia. The receptors have separate functions but may act in concert in several tissues including the small intestine, the visceral yolk sac and the renal proximal tubule to perform significant physiological functions essential to homeostasis in the extracellular fluid compartments. Because of the importance of fluid homeostasis in the inner ear, we investigated the expression of cubilin and megalin in this structure. Furthermore, we examined the binding properties of 6 different aminoglycosides (AGs) to cubilin and compared the results to data obtained for megalin, which is a well-known receptor for AGs and other polybasic substances, including several ototoxic drugs. In the cochlea, immunohistochemical labelling for cubilin showed expression corresponding to the apical surface of the strial marginal cells, to epithelial cells at the spiral prominence and to epithelial cells of Reissner's membrane facing the cochlear duct. In the vestibular apparatus, positive labelling was found in dark cells of the utricle and those flanking the crista ampullaris of the semicircular canals. Exactly the same tissue distribution was found for megalin. These findings support the prevailing view that cubilin and megalin constitute a dual-receptor complex facilitating the function of each other. The physiological role of this receptor complex in the inner ear remains unknown, although several established ligands for both cubilin and megalin are present in the inner ear fluids. Receptor-ligand interaction analysis showed that all 6 AGs bind to both receptors and with approximately the same affinity. The results demonstrate a novel role for cubilin as a drug receptor for AGs and possibly other ototoxic substances.

  16. Cochlear Implantation in Inner Ear Malformations: Systematic Review of Speech Perception Outcomes and Intraoperative Findings.

    Science.gov (United States)

    Farhood, Zachary; Nguyen, Shaun A; Miller, Stephen C; Holcomb, Meredith A; Meyer, Ted A; Rizk, And Habib G

    2017-03-01

    Objective (1) To analyze reported speech perception outcomes in patients with inner ear malformations who undergo cochlear implantation, (2) to review the surgical complications and findings, and (3) to compare the 2 classification systems of Jackler and Sennaroglu. Data Sources PubMed, Scopus (including Embase), Medline, and CINAHL Plus. Review Methods Fifty-nine articles were included that contained speech perception and/or intraoperative data. Cases were differentiated depending on whether the Jackler or Sennaroglu malformation classification was used. A meta-analysis of proportions examined incidences of complete insertion, gusher, and facial nerve aberrancy. For speech perception data, weighted means and standard deviations were calculated for all malformations for short-, medium-, and long-term follow-up. Speech tests were grouped into 3 categories-closed-set words, open-set words, and open-set sentences-and then compared through a comparison-of-means t test. Results Complete insertion was seen in 81.8% of all inner ear malformations (95% CI: 72.6-89.5); gusher was reported in 39.1% of cases (95% CI: 30.3-48.2); and facial nerve anomalies were encountered in 34.4% (95% CI: 20.1-50.3). Significant improvements in average performance were seen for closed- and open-set tests across all malformation types at 12 months postoperatively. Conclusions Cochlear implantation outcomes are favorable for those with inner ear malformations from a surgical and speech outcome standpoint. Accurate classification of anatomic malformations, as well as standardization of postimplantation speech outcomes, is necessary to improve understanding of the impact of implantation in this difficult patient population.

  17. Morphogenesis of the inner ear at different stages of normal human development.

    Science.gov (United States)

    Toyoda, Saki; Shiraki, Naoto; Yamada, Shigehito; Uwabe, Chigako; Imai, Hirohiko; Matsuda, Tetsuya; Yoneyama, Akio; Takeda, Tohoru; Takakuwa, Tetsuya

    2015-12-01

    This study examined the external morphology and morphometry of the human embryonic inner ear membranous labyrinth and documented its three-dimensional position in the developing embryo using phase-contrast X-ray computed tomography and magnetic resonance imaging. A total of 27 samples between Carnegie stage (CS) 17 and the postembryonic phase during trimester 1 (approximately 6-10 weeks after fertilization) were included. The otic vesicle elongated along the dorso-ventral axis and differentiated into the end lymphatic appendage and cochlear duct (CD) at CS 17. The spiral course of the CD began at CS18, with anterior and posterior semicircular ducts (SDs) forming prominent circles with a common crus. The spiral course of the CD comprised more than two turns at the postembryonic phase, at which time the height of the CD was evident. A linear increase was observed in the length of anterior, posterior, and lateral SDs, in that order, and the length of the CD increased exponentially over the course of development. Bending in the medial direction was observed between the cochlear and vestibular parts from the latero-caudal view, with the angle decreasing during development. The position of the inner ear was stable throughout the period of observation on the lateral to ventral side of the rhombencephalon, caudal to the pontine flexure, and adjacent to the auditory ganglia. The plane of the lateral semicircular canal was approximately 8.0°-14.6° with respect to the cranial caudal (z-)axis, indicating that the orientation of the inner ear changes during growth to adulthood.

  18. Transfection using hydroxyapatite nanoparticles in the inner ear via an intact round window membrane in chinchilla

    Science.gov (United States)

    Wu, Xuewen; Ding, Dalian; Jiang, Haiyan; Xing, Xiaowei; Huang, Suping; Liu, Hong; Chen, Zhedong; Sun, Hong

    2012-01-01

    Hydroxyapatite nanoparticles (nHAT) are known to have excellent biocompatibility, and have attracted increasing attention as new candidates of non-viral vectors for gene therapy. In our previous studies, nHAT carrying a therapeutic gene and a reporter gene were successfully transfected into the spiral ganglion neurons in the inner ear of guinea pigs in vivo as well as in the cultured cell lines, although the transfection efficiencies were never higher than 30%. In this study, the surface modification of nHAT with polyethylenimine (PEI) was made (PEI-nHAT, diameter = 73.09 ± 27.32 nm) and a recombinant plasmid carrying enhanced green fluorescent protein (EGFP) gene and neurotrophin-3 (NT-3) gene was constructed as pEGFPC2-NT3. The PEI modified nHAT and the recombinant plasmid was then connected to form the nHAT-based vector-gene complex (PEI-nHAT-pEGFPC2-NT3). This complex was then placed onto the intact round window membranes of the chinchillas for inner ear transfection. Auditory brainstem response (ABR) was tested to evaluate auditory function. Green fluorescence of EGFP was observed using confocal microscopy 48 h after administering vector-gene complexes. There was no significant threshold shift in tone burst-evoked ABR at any tested frequency. Abundant, condensed green fluorescence was found in dark cells on both sides of the crista and around the macula of the utricle. Scattered EGFP signals were also detected in vestibular hair cells, some Schwann cells in the cochlear spiral ganglion region, some outer pillar cells in the organ of Corti, and a few cells in the stria vascularis. The density of green fluorescence-marked cells was obviously higher in the vestibular dark cell area than in other areas of the inner ear, suggesting that vestibular dark cells may have the ability to actively engulf the nHAT-based vector-gene complexes. Considering the high transfection efficiency in the vestibular system, PEI-nHAT may be a potential vector for gene therapy of inner

  19. A comparative study of the inner ear structures of artiodactyls and early cetaceans

    Energy Technology Data Exchange (ETDEWEB)

    Klingshirn, M.A. [Ashland Univ., OH (United States); Luo, Z. [College of Charleston, SC (United States)

    1994-12-31

    It has been suggested that the order Cetacea (whales and porpoises) are closely related to artiodactyls, even-hoofed ungulate mammals such as the pig and cow. Paleontological and molecular data strongly supports this concept of phylogenetic relationships. In a study of DNA sequences of two mitochondrial ribosomal gene segments of cetaceans, the artiodactyls were found to be closest related to Cetaceans. These well accepted studies on the phylogenetic affinities of artiodactyls and cetaceans cause us to conduct a comparative study of the bony structure of the inner ear of these two taxa.

  20. Transfection using hydroxyapatite nanoparticles in the inner ear via an intact round window membrane in chinchilla

    Energy Technology Data Exchange (ETDEWEB)

    Wu Xuewen; Ding Dalian [Central South University, Department of Otolaryngology Head and Neck Surgery, The Third Xiangya Hospital (China); Jiang Haiyan [State University of New York at Buffalo, Center for Hearing and Deafness (United States); XingXiaowei [Central South University, Department of Otolaryngology Head and Neck Surgery, The Third Xiangya Hospital (China); Huang, Suping [Central South University, State Key Laboratory of Powder Metallurgy (China); Liu Hong [Central South University, Department of Otolaryngology Head and Neck Surgery, The Third Xiangya Hospital (China); Chen Zhedong [Central South University, State Key Laboratory of Powder Metallurgy (China); Sun Hong, E-mail: shjhaj@vip.163.com [Central South University, Department of Otolaryngology Head and Neck Surgery, Xiangya Hospital (China)

    2012-01-15

    Hydroxyapatite nanoparticles (nHAT) are known to have excellent biocompatibility, and have attracted increasing attention as new candidates of non-viral vectors for gene therapy. In our previous studies, nHAT carrying a therapeutic gene and a reporter gene were successfully transfected into the spiral ganglion neurons in the inner ear of guinea pigs in vivo as well as in the cultured cell lines, although the transfection efficiencies were never higher than 30%. In this study, the surface modification of nHAT with polyethylenimine (PEI) was made (PEI-nHAT, diameter = 73.09 {+-} 27.32 nm) and a recombinant plasmid carrying enhanced green fluorescent protein (EGFP) gene and neurotrophin-3 (NT-3) gene was constructed as pEGFPC2-NT3. The PEI modified nHAT and the recombinant plasmid was then connected to form the nHAT-based vector-gene complex (PEI-nHAT-pEGFPC2-NT3). This complex was then placed onto the intact round window membranes of the chinchillas for inner ear transfection. Auditory brainstem response (ABR) was tested to evaluate auditory function. Green fluorescence of EGFP was observed using confocal microscopy 48 h after administering vector-gene complexes. There was no significant threshold shift in tone burst-evoked ABR at any tested frequency. Abundant, condensed green fluorescence was found in dark cells on both sides of the crista and around the macula of the utricle. Scattered EGFP signals were also detected in vestibular hair cells, some Schwann cells in the cochlear spiral ganglion region, some outer pillar cells in the organ of Corti, and a few cells in the stria vascularis. The density of green fluorescence-marked cells was obviously higher in the vestibular dark cell area than in other areas of the inner ear, suggesting that vestibular dark cells may have the ability to actively engulf the nHAT-based vector-gene complexes. Considering the high transfection efficiency in the vestibular system, PEI-nHAT may be a potential vector for gene therapy of

  1. [Pressure relations between endocranial and intracochlear fluid spaces in patients with inner ear diseases].

    Science.gov (United States)

    Gosepath, K; Maurer, J; Pelster, H; Thews, O; Mann, W

    1995-03-01

    Intracranial pressure is transmitted to the perilymph of the cochlea via the cochlear aquaeduct and via Reissner's membrane to the endolymph. The "Tympanic Membrane Displacement Analyser (TDA)" is a new device that may be a useful non-invasive method to show intracranial and intracochlear pressure changes indirectly measured by tympanic membrane displacement during stapedial reflex contraction. The TDA was utilised in 20 normal persons and in 29 patients with unilateral diseases of the inner ear. No significant differences in the tympanic membrane displacement were found between patients with sensorineural hearing loss, patients with Ménière's disease, and normal persons.

  2. Petrosal anatomy and inner ear structures of the Late Jurassic Henkelotherium (Mammalia, Cladotheria, Dryolestoidea): insight into the early evolution of the ear region in cladotherian mammals

    Science.gov (United States)

    Ruf, Irina; Luo, Zhe-Xi; Wible, John R; Martin, Thomas

    2009-01-01

    The petrosal anatomy and inner ear structure of Jurassic cladotherian mammals represent the ancestral morphological conditions (groundplan) from which modern therian mammals (marsupials and placentals) have evolved. We present the reconstruction of the petrosal and inner ear features of the Late Jurassic dryolestoid mammal Henkelotherium guimarotae from high-resolution computed tomography and three-dimensional imaging analysis. This study of Henkelotherium revealed a combination of derived and primitive features, including: cladotherian apomorphies, such as the promontorial sulcus for the internal carotid artery and reduced lateral trough; trechnotherian characters, such as an enclosed cochlear canaliculus for the perilymphatic duct, post-promontorial tympanic sinus and caudal tympanic process; in addition to plesiomorphic mammalian features, such as the cavum supracochleare and prootic canal. The inner ear of Henkelotherium shows a division between the utricle and saccule, a cochlear canal coiled through at least 270°, a distinctive primary bony lamina for the basilar membrane, and a secondary bony lamina. The development of the primary and secondary bony laminae in the cochlear canal is suggested here to be correlated with the concurrent coiling of the bony canal and membranous duct of the inner ear cochlea, apomorphies of the more inclusive cladotherian clade that also represent the ancestral morphotype of modern therian mammals. Because these features are crucial for high-frequency hearing in extant therian mammals, their early appearance in Late Jurassic cladotherians suggests a more ancient origination for high-frequency hearing in mammalian history than previously thought. PMID:19438763

  3. Petrosal anatomy and inner ear structures of the Late Jurassic Henkelotherium (Mammalia, Cladotheria, Dryolestoidea): insight into the early evolution of the ear region in cladotherian mammals.

    Science.gov (United States)

    Ruf, Irina; Luo, Zhe-Xi; Wible, John R; Martin, Thomas

    2009-05-01

    The petrosal anatomy and inner ear structure of Jurassic cladotherian mammals represent the ancestral morphological conditions (groundplan) from which modern therian mammals (marsupials and placentals) have evolved. We present the reconstruction of the petrosal and inner ear features of the Late Jurassic dryolestoid mammal Henkelotherium guimarotae from high-resolution computed tomography and three-dimensional imaging analysis. This study of Henkelotherium revealed a combination of derived and primitive features, including: cladotherian apomorphies, such as the promontorial sulcus for the internal carotid artery and reduced lateral trough; trechnotherian characters, such as an enclosed cochlear canaliculus for the perilymphatic duct, post-promontorial tympanic sinus and caudal tympanic process; in addition to plesiomorphic mammalian features, such as the cavum supracochleare and prootic canal. The inner ear of Henkelotherium shows a division between the utricle and saccule, a cochlear canal coiled through at least 270 degrees, a distinctive primary bony lamina for the basilar membrane, and a secondary bony lamina. The development of the primary and secondary bony laminae in the cochlear canal is suggested here to be correlated with the concurrent coiling of the bony canal and membranous duct of the inner ear cochlea, apomorphies of the more inclusive cladotherian clade that also represent the ancestral morphotype of modern therian mammals. Because these features are crucial for high-frequency hearing in extant therian mammals, their early appearance in Late Jurassic cladotherians suggests a more ancient origination for high-frequency hearing in mammalian history than previously thought.

  4. Inner ear hair cells deteriorate in mice engineered to have no or diminished innervation.

    Directory of Open Access Journals (Sweden)

    Jennifer eKersigo

    2015-03-01

    Full Text Available The innervation of the inner ear critically depends on the two neurotrophins Ntf3 and Bdnf. In contrast to this molecularly well established dependency, evidence regarding the need of innervation for long-term maintenance of inner ear hair cells is inconclusive due to experimental variability. Mutant mice that lack both neurotrophins could shed light on the long-term consequences of innervation loss on hair cells without introducing experimental variability, but do not survive after birth. Mutant mice with conditional deletion of both neurotrophins lose almost all innervation by postnatal day 10 and show an initially normal development of hair cells by this stage. No innervation remains after three weeks and complete loss of all innervation results in near complete loss of outer and many inner hair cells of the organ of Corti within 4 months. Mutants that retain one allele of either neurotrophin have only partial loss of innervation of the organ of Corti and show a longer viability of cochlear hair cells with more profound loss of inner hair cells. Ultimately, however, hair cells disappear with a base to apex progression, proportional to the residual density of innervation and similar to carboplatin ototoxicity. Similar to reports of hair cell loss after aminoglycoside treatment, blobbing of stereocilia of apparently dying hair cells protrude into the cochlear duct. Denervation of vestibular sensory epithelia for several months also resulted in variable results, ranging from unusual hair cells resembling the aberrations found in the organ of Corti, to near normal hair cells in the canal cristae. Fusion and/or resorption of stereocilia and loss of hair cells follows a pattern reminiscent of Myo6 and Cdc42 null mice. Our data support a role of innervation for long-term maintenance but with a remarkable local variation that needs to be taken into account when attempting regeneration of the organ of Corti.

  5. Acoustic emissions from the inner ear and brain stem responses in type 2 diabetics

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    Jabbari Moghaddam Y

    2011-12-01

    Full Text Available Yalda Jabbari MoghaddamDepartment of Otolaryngology, Head and Neck Surgery, Tabriz University of Medical Sciences, Tabriz, IranBackground: The purpose of this study was to evaluate the auditory brain stem response (ABR and acoustic emissions of the inner ear (OAE in middle-aged type 2 diabetics.Methods: Fifty type 2 diabetic and nondiabetic patients aged 40–50 years and attending the Tabriz Medical University outpatient clinics were recruited for this study during 2009–2010. All ABR and OAE procedures were implemented by an audiometrist. The relationship between ABR and OAE findings and demographic, laboratory, and clinical characteristics was investigated.Results: Fifty patients (34 female and 16 male of average age 45.7 ± 3.0 years were entered into the study. In the type 2 diabetic group, disordered ABR was found in at least one ear in 8% of cases and disordered OAE was recorded in at least one ear in 16% of cases, with no significant difference between the diabetic and nondiabetic groups. Mean age, duration of diabetes, serum HbA1c levels, and prevalence of female gender were higher in the diabetic group.Conclusion: According to our findings, the prevalence of ABR and OAE is not significantly different between type 2 diabetics and nondiabetics.Keywords: sensorineural hearing loss, diabetes, auditory brain stem response, otoacoustic emission

  6. Inner Ear Disease and Benign Paroxysmal Positional Vertigo: A Critical Review of Incidence, Clinical Characteristics, and Management

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    M. Riga

    2011-01-01

    Full Text Available Background. This study is a review of the incidence, clinical characteristics, and management of secondary BPPV. The different subtypes of secondary BPPV are compared to each other, as well as idiopathic BPPV. Furthermore, the study highlights the coexistence of BPPV with other inner ear pathologies. Methods. A comprehensive search for articles including in the abstract information on incidence, clinical characteristics, and management of secondary BPPV was conducted within the PubMed library. Results. Different referral patterns, different diagnostic criteria used for inner ear diseases, and different patient populations have led to greatly variable incidence results. The differences regarding clinical characteristics and treatment outcomes may support the hypothesis that idiopathic BPPV and the various subtypes of secondary BPPV do not share the exact same pathophysiological mechanisms. Conclusions. Secondary BPPV is often under-diagnosed, because dizziness may be atypical and attributed to the primary inner ear pathology. Reversely, a limited number of BPPV patients may not be subjected to a full examination and characterized as idiopathic, while other inner ear diseases are underdiagnosed. A higher suspicion index for the coexistence of BPPV with other inner ear pathologies, may lead to a more integrated diagnosis and consequently to a more efficient treatment of these patients.

  7. Development of gene therapy for inner ear disease: Using bilateral vestibular hypofunction as a vehicle for translational research.

    Science.gov (United States)

    Staecker, Hinrich; Praetorius, Mark; Brough, Douglas E

    2011-06-01

    Despite the significant impact of hearing and balance disorders on the general population there are currently no dedicated pharmaceuticals that target the inner ear. Advances in molecular biology and neuroscience have improved our understanding of the inner ear allowing the development of a range of molecular targets that have the potential to treat both hearing and balance disorders. One of the principal advantages of the inner ear is that it is accessible through a variety of approaches that would allow a potential to be delivered locally rather than systemically. This significantly broadens the potential medications that can be developed and opens the possibility of local gene delivery as a therapeutic intervention. Several potential clinical targets have been identified including delivery of neurotrophin expressing genes as an adjunct to cochlear implantation, delivery of protective genes to prevent trauma and the development of strategies for regenerating inner ear sensory cells. In order to translate these potential therapeutics into humans we will want to optimize the gene delivery methodology, dosing and activity of the drug for therapeutic value. To this end we have developed a series of adenovectors that efficiently transduce the inner ear. The use of these gene delivery approaches are attractive for the potential of hair cell regeneration after loss induced by trauma or ototoxins. This approach is particularly suited for the development of molecular therapies targeted at the vestibular system given that no device based therapeutic such a cochlear implant available for vestibular loss.

  8. Reconstruction of Cochlea Based on Micro-CT and Histological Images of the Human Inner Ear

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    Christos Bellos

    2014-01-01

    Full Text Available The study of the normal function and pathology of the inner ear has unique difficulties as it is inaccessible during life and, so, conventional techniques of pathologic studies such as biopsy and surgical excision are not feasible, without further impairing function. Mathematical modelling is therefore particularly attractive as a tool in researching the cochlea and its pathology. The first step towards efficient mathematical modelling is the reconstruction of an accurate three dimensional (3D model of the cochlea that will be presented in this paper. The high quality of the histological images is being exploited in order to extract several sections of the cochlea that are not visible on the micro-CT (mCT images (i.e., scala media, spiral ligament, and organ of Corti as well as other important sections (i.e., basilar membrane, Reissner membrane, scala vestibule, and scala tympani. The reconstructed model is being projected in the centerline of the coiled cochlea, extracted from mCT images, and represented in the 3D space. The reconstruction activities are part of the SIFEM project, which will result in the delivery of an infrastructure, semantically interlinking various tools and libraries (i.e., segmentation, reconstruction, and visualization tools with the clinical knowledge, which is represented by existing data, towards the delivery of a robust multiscale model of the inner ear.

  9. Characterization and development of an inner ear type I fibrocyte cell culture.

    Science.gov (United States)

    Gratton, M A; Schulte, B A; Hazen-Martin, D J

    1996-09-15

    A method has been developed that allows successful maintenance of secondary cell cultures derived from explants of the cochlear lateral wall of young adult gerbils. The secondary cultures were characterized morphologically with light and transmission electron microscopy and immunocytochemically with protein markers specific to various lateral wall cell types. Structural studies revealed fusiform-shaped cells with a paucity of cytoplasm surrounding the nucleus and slender processes. The cells showed little evidence of intercellular contact even when confluent. The cultures were immunopositive for vimentin, carbonic anhydrase isozyme II, creatine kinase isozyme BB and smooth endoplasmic reticulum Ca-ATPase, but lacked reactivity for cytokeratins and Na,K-ATPase. The results indicate that the cultures are comprised of type I fibrocytes from the spiral ligament. These findings are the first to demonstrate that inner ear spiral ligament cells can be isolated and maintained in secondary culture while retaining many of their in vivo characteristics. Based upon their location and content of ion transport enzymes, type I fibrocytes are thought to be involved in the recycling of potassium from perilymph into the stria vascularis. The establishment of this cell line provides a means to analyze the role of spiral ligament fibrocytes in maintenance of inner ear homeostasis.

  10. Exogenous material in the inner ear of the adult Port Jackson shark, Heterodontus portusjacksoni (Elasmbranchii).

    Science.gov (United States)

    Mills, Morena; Rasch, Ron; Siebeck, Ulrike E; Collin, Shaun P

    2011-03-01

    Previous studies have suggested that the inner ear of some benthic species of elasmobranchs contain only exogenous material within their otoconial organs, a unique feature within vertebrates. However, these examinations have not accounted for the possibility of otoconial degeneration or used modern experimental methods to identify the materials present. Both of these issues are addressed in this study using inner ear samples from the adult Port Jackson shark, Heterodontus portusjacksoni. A comparison of the otoconial mass in fixed specimens over short and medium time scales reveals that over those timescales the degeneration of calcium carbonate-based otoconia does not occur and confirms that calcium carbonate-based otoconia are not found within the otoconial organs of H. portusjacksoni. Additionally, microanalysis of the chemical composition and ultrastructure of the otoconial mass using energy dispersive X-ray microanalysis and scanning electron microscopy confirms that the entire otoconial mass is comprised of exogenous silicon dioxide particles, bound within a carbon matrix. This exogenous material is suggested to play an equivalent role to the otoconia found in other species of elasmobranchs, and allows both hearing and vestibular control to occur in benthic sharks that spend their lives foraging within a sandy substrate. Copyright © 2011 Wiley-Liss, Inc.

  11. Morphological variation among the inner ears of extinct and extant baleen whales (Cetacea: Mysticeti).

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    Ekdale, Eric G

    2016-12-01

    Living mysticetes (baleen whales) and odontocetes (toothed whales) differ significantly in auditory function in that toothed whales are sensitive to high-frequency and ultrasonic sound vibrations and mysticetes to low-frequency and infrasonic noises. Our knowledge of the evolution and phylogeny of cetaceans, and mysticetes in particular, is at a point at which we can explore morphological and physiological changes within the baleen whale inner ear. Traditional comparative anatomy and landmark-based 3D-geometric morphometric analyses were performed to investigate the anatomical diversity of the inner ears of extinct and extant mysticetes in comparison with other cetaceans. Principal component analyses (PCAs) show that the cochlear morphospace of odontocetes is tangential to that of mysticetes, but odontocetes are completely separated from mysticetes when semicircular canal landmarks are combined with the cochlear data. The cochlea of the archaeocete Zygorhiza kochii and early diverging extinct mysticetes plot within the morphospace of crown mysticetes, suggesting that mysticetes possess ancestral cochlear morphology and physiology. The PCA results indicate variation among mysticete species, although no major patterns are recovered to suggest separate hearing or locomotor regimes. Phylogenetic signal was detected for several clades, including crown Cetacea and crown Mysticeti, with the most clades expressing phylogenetic signal in the semicircular canal dataset. Brownian motion could not be excluded as an explanation for the signal, except for analyses combining cochlea and semicircular canal datasets for Balaenopteridae. J. Morphol. 277:1599-1615, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  12. The inner ear of Megatherium and the evolution of the vestibular system in sloths.

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    Billet, G; Germain, D; Ruf, I; de Muizon, C; Hautier, L

    2013-12-01

    Extant tree sloths are uniquely slow mammals with a very specialized suspensory behavior. To improve our understanding of their peculiar evolution, we investigated the inner ear morphology of one of the largest and most popular fossil ground sloths, Megatherium americanum. We first address the predicted agility of this animal from the scaling of its semicircular canals (SC) relative to body mass, based on recent work that provided evidence that the size of the SC in mammals correlates with body mass and levels of agility. Our analyses predict intermediate levels of agility for Megatherium, contrasting with the extreme slowness of extant sloths. Secondly, we focus on the morphology of the SC at the inner ear scale and investigate the shape and proportions of these structures in Megatherium and in a large diversity of extant xenarthrans represented in our database. Our morphometric analyses demonstrate that the giant ground sloth clearly departs from the SC morphology of both extant sloth genera (Choloepus, Bradypus) and is in some aspects closer to that of armadillos and anteaters. Given the close phylogenetic relationships of Megatherium with the extant genus Choloepus, these results are evidence of substantial homoplasy of the SC anatomy in sloths. This homoplasy most likely corresponds to an outstanding convergent evolution between extant suspensory sloth genera.

  13. An elastic element in the protocadherin-15 tip link of the inner ear

    Science.gov (United States)

    Araya-Secchi, Raul; Neel, Brandon L.; Sotomayor, Marcos

    2016-11-01

    Tip link filaments convey force and gate inner-ear hair-cell transduction channels to mediate perception of sound and head movements. Cadherin-23 and protocadherin-15 form tip links through a calcium-dependent interaction of their extracellular domains made of multiple extracellular cadherin (EC) repeats. These repeats are structurally similar, but not identical in sequence, often featuring linkers with conserved calcium-binding sites that confer mechanical strength to them. Here we present the X-ray crystal structures of human protocadherin-15 EC8-EC10 and mouse EC9-EC10, which show an EC8-9 canonical-like calcium-binding linker, and an EC9-10 calcium-free linker that alters the linear arrangement of EC repeats. Molecular dynamics simulations and small-angle X-ray scattering experiments support this non-linear conformation. Simulations also suggest that unbending of EC9-10 confers some elasticity to otherwise rigid tip links. The new structure provides a first view of protocadherin-15's non-canonical EC linkers and suggests how they may function in inner-ear mechanotransduction, with implications for other cadherins.

  14. Inner ear drug delivery via a reciprocating perfusion system in the guinea pig.

    Science.gov (United States)

    Chen, Zhiqiang; Kujawa, Sharon G; McKenna, Michael J; Fiering, Jason O; Mescher, Mark J; Borenstein, Jeffrey T; Swan, Erin E Leary; Sewell, William F

    2005-12-10

    Rapid progress in understanding the molecular mechanisms associated with cochlear and auditory nerve degenerative processes offers hope for the development of gene-transfer and molecular approaches to treat these diseases in patients. For therapies based on these discoveries to become clinically useful, it will be necessary to develop safe and reliable mechanisms for the delivery of drugs into the inner ear, bypassing the blood-labyrinthine barrier. Toward the goal of developing an inner ear perfusion device for human use, a reciprocating microfluidic system that allows perfusion of drugs into the cochlear perilymph through a single inlet hole in scala tympani of the basal turn was developed. The performance of a prototype, extracorporeal reciprocating perfusion system in guinea pigs is described. Analysis of the cochlear distribution of compounds after perfusion took advantage of the place-dependent generation of responses to tones along the length of the cochlea. Perfusion with a control artificial perilymph solution had no effect. Two drugs with well-characterized effects on cochlear physiology, salicylate (5 mM) and DNQX (6,7-Dinitroquinoxaline-2,3-dione; 100 and 300 microM), reversibly altered responses. The magnitude of drug effect decreased with distance from the perfusion pipette for up to 10 mm, and increased with dose and length of application.

  15. Comparative Anatomy of the Bony Labyrinth (Inner Ear of Placental Mammals.

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    Eric G Ekdale

    Full Text Available Variation is a naturally occurring phenomenon that is observable at all levels of morphology, from anatomical variations of DNA molecules to gross variations between whole organisms. The structure of the otic region is no exception. The present paper documents the broad morphological diversity exhibited by the inner ear region of placental mammals using digital endocasts constructed from high-resolution X-ray computed tomography (CT. Descriptions cover the major placental clades, and linear, angular, and volumetric dimensions are reported.The size of the labyrinth is correlated to the overall body mass of individuals, such that large bodied mammals have absolutely larger labyrinths. The ratio between the average arc radius of curvature of the three semicircular canals and body mass of aquatic species is substantially lower than the ratios of related terrestrial taxa, and the volume percentage of the vestibular apparatus of aquatic mammals tends to be less than that calculated for terrestrial species. Aspects of the bony labyrinth are phylogenetically informative, including vestibular reduction in Cetacea, a tall cochlear spiral in caviomorph rodents, a low position of the plane of the lateral semicircular canal compared to the posterior canal in Cetacea and Carnivora, and a low cochlear aspect ratio in Primatomorpha.The morphological descriptions that are presented add a broad baseline of anatomy of the inner ear across many placental mammal clades, for many of which the structure of the bony labyrinth is largely unknown. The data included here complement the growing body of literature on the physiological and phylogenetic significance of bony labyrinth structures in mammals, and they serve as a source of data for future studies on the evolution and function of the vertebrate ear.

  16. Hush puppy: a new mouse mutant with pinna, ossicle, and inner ear defects.

    Science.gov (United States)

    Pau, Henry; Fuchs, Helmut; de Angelis, Martin Hrabé; Steel, Karen P

    2005-01-01

    Deafness can be associated with abnormalities of the pinna, ossicles, and cochlea. The authors studied a newly generated mouse mutant with pinna defects and asked whether these defects are associated with peripheral auditory or facial skeletal abnormalities, or both. Furthermore, the authors investigated where the mutation responsible for these defects was located in the mouse genome. The hearing of hush puppy mutants was assessed by Preyer reflex and electrophysiological measurement. The morphological features of their middle and inner ears were investigated by microdissection, paint-filling of the labyrinth, and scanning electron microscopy. Skeletal staining of skulls was performed to assess the craniofacial dimensions. Genome scanning was performed using microsatellite markers to localize the mutation to a chromosomal region. Some hush puppy mutants showed early onset of hearing impairment. They had small, bat-like pinnae and normal malleus but abnormal incus and stapes. Some mutants had asymmetrical defects and showed reduced penetrance of the ear abnormalities. Paint-filling of newborns' inner ears revealed no morphological abnormality, although half of the mice studied were expected to carry the mutation. Reduced numbers of outer hair cells were demonstrated in mutants' cochlea on scanning electron microscopy. Skeletal staining showed that the mutants have significantly shorter snouts and mandibles. Genome scan revealed that the mutation lies on chromosome 8 between markers D8Mit58 and D8Mit289. The study results indicate developmental problems of the first and second branchial arches and otocyst as a result of a single gene mutation. Similar defects are found in humans, and hush puppy provides a mouse model for investigation of such defects.

  17. Homozygous FGF3 mutations result in congenital deafness with inner ear agenesis, microtia, and microdontia.

    Science.gov (United States)

    Tekin, M; Oztürkmen Akay, H; Fitoz, S; Birnbaum, S; Cengiz, F B; Sennaroğlu, L; Incesulu, A; Yüksel Konuk, E B; Hasanefendioğlu Bayrak, A; Sentürk, S; Cebeci, I; Utine, G E; Tunçbilek, E; Nance, W E; Duman, D

    2008-06-01

    Homozygous mutations in the fibroblast growth factor 3 (FGF3) gene have recently been discovered in an autosomal recessive form of syndromic deafness characterized by complete labyrinthine aplasia (Michel aplasia), microtia, and microdontia (OMIM 610706 - LAMM). In order to better characterize the phenotypic spectrum associated with FGF3 mutations, we sequenced the FGF3 gene in 10 unrelated families in which probands had congenital deafness associated with various inner ear anomalies, including Michel aplasia, with or without tooth or external ear anomalies. FGF3 sequence changes were not found in eight unrelated probands with isolated inner ear anomalies or with a cochlear malformation along with auricle and tooth anomalies. We identified two new homozygous FGF3 mutations, p.Leu6Pro (c.17T>C) and p. Ile85MetfsX15 (c.254delT), in four subjects from two unrelated families with LAMM. The p.Leu6Pro mutation occurred within the signal site of FGF3 and is predicted to impair its secretion. The c.254delT mutation results in truncation of FGF3. Both mutations completely co-segregated with the phenotype, and heterozygotes did not have any of the phenotypic findings of LAMM. Some affected children had large skin tags on the upper side of the auricles, which is a distinctive clinical component of the syndrome. Enlarged collateral emissary veins associated with stenosis of the jugular foramen were noted on computerized tomographies of most affected subjects with FGF3 mutations. However, similar venous anomalies were also detected in persons with non-syndromic Michel aplasia, suggesting that a direct causative role of impaired FGF3 signaling is unlikely.

  18. A late role for bmp2b in the morphogenesis of semicircular canal ducts in the zebrafish inner ear.

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    Katherine L Hammond

    Full Text Available The Bone Morphogenetic Protein (BMP genes bmp2 and bmp4 are expressed in highly conserved patterns in the developing vertebrate inner ear. It has, however, proved difficult to elucidate the function of BMPs during ear development as mutations in these genes cause early embryonic lethality. Previous studies using conditional approaches in mouse and chicken have shown that Bmp4 has a role in semicircular canal and crista development, but there is currently no direct evidence for the role of Bmp2 in the developing inner ear.We have used an RNA rescue strategy to test the role of bmp2b in the zebrafish inner ear directly. Injection of bmp2b or smad5 mRNA into homozygous mutant swirl (bmp2b(-/- embryos rescues the early patterning defects in these mutants and the fish survive to adulthood. As injected RNA will only last, at most, for the first few days of embryogenesis, all later development occurs in the absence of bmp2b function. Although rescued swirl adult fish are viable, they have balance defects suggestive of vestibular dysfunction. Analysis of the inner ears of these fish reveals a total absence of semicircular canal ducts, structures involved in the detection of angular motion. All other regions of the ear, including the ampullae and cristae, are present and appear normal. Early stages of otic development in rescued swirl embryos are also normal.Our findings demonstrate a critical late role for bmp2b in the morphogenesis of semicircular canals in the zebrafish inner ear. This is the first demonstration of a developmental role for any gene during post-embryonic stages of otic morphogenesis in the zebrafish. Despite differences in the early stages of semicircular canal formation between zebrafish and amniotes, the role of Bmp2 in semicircular canal duct outgrowth is likely to be conserved between different vertebrate species.

  19. Registering grades of sudden deafness to predict the hearing outcome via an inner-ear test battery.

    Science.gov (United States)

    You, Tsung-Zoo; Wang, Shou-Jen; Young, Yi-Ho

    2014-03-01

    An inner ear test battery comprising audiometry and ocular vestibular-evoked myogenic potential (oVEMP), cervical VEMP (cVEMP), and caloric tests was applied to patients with sudden deafness to map their lesions and predict hearing outcome. Retrospective study. Seventy-five patients with unilateral sudden deafness underwent an inner-ear test battery. Registering the grades of sudden deafness was based on the number of abnormal test results in the inner ear test battery. After treatment for three consecutive months, mean hearing gain declined significantly from Grade I (one abnormal test) to Grade IV (four abnormal tests). Significant relations existed between hearing outcome and oVEMP test results (p sudden deafness patients may indicate poor prognosis for hearing improvement, whereas hearing recovery can be anticipated when both tests reveal normal responses.

  20. Intratympanic delivery of oligoarginine-conjugated nanoparticles as a gene (or drug) carrier to the inner ear.

    Science.gov (United States)

    Yoon, Ji Young; Yang, Keum-Jin; Kim, Da Eun; Lee, Kyu-Yup; Park, Shi-Nae; Kim, Dong-Kee; Kim, Jong-Duk

    2015-12-01

    A drug delivery system to the inner ear using nanoparticles consisting of oligoarginine peptide (Arg8) conjugated to poly(amino acid) (poly(2-hydroxyethyl L-aspartamide; PHEA) was investigated to determine whether the limitations of low drug transport levels across the round window membrane (RWM) and poor transport into inner ear target cells, including hair cells and spiral ganglion, could be overcome. Three types of carrier materials, PHEA-g-C18, PHEA-g-Arg8, and PHEA-g-C18-Arg8, were synthesized to examine the effects of oligoarginine and morphology of the synthesized carriers. Nile red (NR) was used as a fluorescent indicator as well as to model a hydrophobic drug. Compared with PHEA-g-C18-NR nanoparticles, the oligoarginine-conjugated nanoparticles of PHEA-g-C18-Arg8-NR and PHEA-g-Arg8-NR entered into HEI-OC1 cells at significant levels. Furthermore, the strongest fluorescence intensity was observed in nuclei when PHEA-g-C18-Arg8 nanoparticles were used. The high uptake rates of PHEA-g-C18 and PHEA-g-C18-Arg8 nanoparticles were observed in ex vivo experiments using hair cells. After the delivery of PHEA-g-C18-Arg8 nanoparticles with reporter gene transfer, EGFP (enhanced green fluorescent protein) expression was monitored as an indicator of gene delivery. In the inner ear cells, PHEA-g-C18-Arg8 nanoparticles showed comparable or better transfection capabilities than the commercially available Lipofectamine reagent. PHEA-g-C18-Arg8 penetrated in vivo across the RWM of C57/BL6 mice with Nile red staining and GFP expression in various inner ear tissues. In conclusion, PHEA-g-C18-Arg8 nanoparticles were successfully transported into the inner ear through the intratympanic route and are proposed as promising candidates as delivery carriers to address inner ear diseases.

  1. Middle and inner ear malformations in two siblings exposed to valproic acid during pregnancy: a case report.

    Science.gov (United States)

    Van Houtte, Evelyne; Casselman, Jan; Janssens, Sandra; De Kegel, Alexandra; Maes, Leen; Dhooge, Ingeborg

    2014-11-01

    Valproic acid (VPA) is a known teratogenic drug. Exposure to VPA during the pregnancy can lead to a distinct facial appearance, a cluster of major and minor anomalies and developmental delay. In this case report, two siblings with fetal valproate syndrome and a mild conductive hearing loss were investigated. Radiologic evaluation showed middle and inner ear malformations in both children. Audiologic, vestibular and motor examination was performed. This is the first case report to describe middle and inner ear malformations in children exposed to VPA.

  2. Assessing cisplatin-induced ototoxicity and otoprotection in whole organ culture of the mouse inner ear in simulated microgravity.

    Science.gov (United States)

    Tropitzsch, Anke; Arnold, Heinz; Bassiouni, Mohamed; Müller, Andrea; Eckhard, Andreas; Müller, Marcus; Löwenheim, Hubert

    2014-06-16

    Cisplatin is a widely used anti-cancer drug. Ototoxicity is a major dose-limiting side-effect. A reproducible mammalian in-vitro model of cisplatin ototoxicity is required to screen and validate otoprotective drug candidates. We utilized a whole organ culture system of the postnatal mouse inner ear in a rotating wall vessel bioreactor under "simulated microgravity" culture conditions. As previously described this system allows whole organ culture of the inner ear and quantitative assessment of ototoxic effects of aminoglycoside induced hair cell loss. Here we demonstrate that this model is also applicable to the assessment of cisplatin induced ototoxicity. In this model cisplatin induced hair cell loss was dose and time dependent. Increasing exposure time of cisplatin led to decreasing EC50 concentrations. Outer hair cells were more susceptible than inner hair cells, and hair cells in the cochlear base were more susceptible than hair cells in the cochlear apex. Initial cisplatin dose determined the final extent of hair cell loss irrespective if the drug was withdrawn or continued. Dose dependant otoprotection was demonstrated by co-administration of the antioxidant agent N-acetyl l-cysteine. The results support the use of this inner ear organ culture system as an in vitro assay and validation platform for inner ear toxicology and the search for otoprotective compounds. Copyright © 2014 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  3. Irradiation damage to frog inner ear during synchrotron radiation tomographic investigation

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    Boistel, Renaud [Equipe Communications Acoustiques, NAMC, CNRS UMR 8620, F-91405 Orsay (France); CNRS UMR 7179 ' Mecanismes adaptatifs: des organismes aux communautes' , Departement ' Ecologie et Gestion de la Biodiversite' , Museum National d' Histoire Naturelle, 57 rue Cuvier, case postale 55, 75231 Paris Cedex 5 (France); Univ Paris Sud, F-91405 Orsay (France); European Synchrotron Radiation Facility, B.P. 220, F-38043 Grenoble (France)], E-mail: boistel@mnhn.fr; Pollet, Nicolas [Univ Paris Sud, F-91405 Orsay (France); CNRS UMR 8080, F-91405 Orsay (France); Epigenomics Project, Genopole, Univ Evry Val d' Essonne, 91034 Evry Cedex (France); Tinevez, Jean-Yves [Laboratoire Physico-Chimie Curie, CNRS UMR 168, Institut Curie Recherche, 26, Rue d' Ulm, 75248 Paris Cedex 05 (France); Cloetens, Peter [European Synchrotron Radiation Facility, B.P. 220, F-38043 Grenoble (France); Schlenker, Michel [Institut Neel, CNRS, and Grenoble Institute of Technology, B.P. 166, F-38042 Grenoble (France)

    2009-03-15

    Unexpectedly severe radiation damage, showing up through deformation of the saccule, was encountered during a synchrotron radiation high-resolution (700 nm pixel size) tomographic observation of an inner ear, fixed in a formaldehyde solution, of the frog Rana esculenta. The visible displacement of the edge of the otoconia-filled part of the saccule amounted to about 100 {mu}m after an irradiation with 20.5 keV X-ray photons corresponding to a dose of 1.5 kGy for the protein matrix. The close-knit coexistence of organic and mineral components in the biological tissue may be linked to the dramatic increase of radiation dosage sensitivity.

  4. Histone deacetylase 1 is required for the development of the zebrafish inner ear

    Science.gov (United States)

    He, Yingzi; Tang, Dongmei; Li, Wenyan; Chai, Renjie; Li, Huawei

    2016-01-01

    Histone deacetylase 1 (HDAC1) has been reported to be important for multiple aspects of normal embryonic development, but little is known about its function in the development of mechanosensory organs. Here, we first confirmed that HDAC1 is expressed in the developing otic vesicles of zebrafish by whole-mount in situ hybridization. Knockdown of HDAC1 using antisense morpholino oligonucleotides in zebrafish embryos induced smaller otic vesicles, abnormal otoliths, malformed or absent semicircular canals, and fewer sensory hair cells. HDAC1 loss of function also caused attenuated expression of a subset of key genes required for otic vesicle formation during development. Morpholino-mediated knockdown of HDAC1 resulted in decreased expression of members of the Fgf family in the otic vesicles, suggesting that HDAC1 is involved in the development of the inner ear through regulation of Fgf signaling pathways. Taken together, our results indicate that HDAC1 plays an important role in otic vesicle formation. PMID:26832938

  5. Imaging assessment of profound sensorineural deafness with inner ear anatomical abnormalities

    Institute of Scientific and Technical Information of China (English)

    Wei-Jing Wu; Xin Chen; Jing-Kun Li; Tao Peng; Yun-Peng Dong; Xue-Zhong Liu; Ding-Hua Xie; Xiang-Bo He; Li-Hua Tan; Peng Hu; An-Quan Peng; Zi-An Xiao; Shu Yang; Tian Wang; Jie Qing

    2015-01-01

    Objective: :To explore the value of a combined computed tomography (CT) and magnetic resonance imaging (MRI) in evaluating profound sensorineural deafness patients before cochlear implant (CI) surgery. Methods:A retrospective analysis of 1012 cases of profound sensorineural deafness that received CI was performed. Results:A total of 96 cases were diagnosed with inner ear abnormalities including large vestibular aqueduct syndrome (LVAS, n ¼ 61), Michel deformity (n ¼ 3), cochlear incomplete partition I (n ¼ 2), cochlear incomplete partition II (n ¼ 6), cochlear hypoplasia with vestibular malformation (n ¼ 3), cochlear ossification (n ¼ 3), bilateral internal auditory canal obstruction (n ¼ 5) and internal auditory canal stenosis (n ¼ 2). Conclusion:High resolution CT (HRCT) can display bony structures while MRI can image the membranous labyrinth in preoperative evaluation for cochlear implantation. The combination of these two modalities provides reliable anatomical information regarding the bony and mem-branous labyrinths, as well as the auditory nerve.

  6. Diseases of the inner ear. A clinical, radiologic, and pathologic atlas

    Energy Technology Data Exchange (ETDEWEB)

    Motasaddi Zarandy, Masoud [Tehran Univ. of Medical Sciences Amiralam Hospital (Iran). Cochlear Implant Dept.; Rutka, John [Toronto Univ., ON (Canada). Dept. Otolaryngology-Head and Neck, Centre for Advanced Hearing

    2010-07-01

    This book is a comprehensive atlas of the clinical conditions that commonly involve the inner ear and lateral skull base. Each disorder or disease is meticulously and beautifully illustrated, with accompanying informative text. An important feature of the book is that no disorder is described from a single point of view. Instead, the clinical features are linked with both radiologic and pathologic findings to provide an all-encompassing picture of the condition in question. This is feasible because the book is the result of years of intense collaborative teamwork between departments at the University of Toronto and the Tehran University of Medical Sciences, and includes many clinical and pathologic images that could only be acquired in major referral units. It is anticipated that this atlas will assist greatly in improving collaboration between clinicians and surgeons in the diagnostic, therapeutic, and surgical management of disorders in this challenging area. (orig.)

  7. Multimodal optical imager for inner ear hearing loss diagnosis (Conference Presentation)

    Science.gov (United States)

    Park, Jesung; Maguluri, Gopi N.; Zhao, Youbo; Iftimia, Nicusor V.

    2017-02-01

    Sensorineural hearing loss (SNHL), which typically originates in the cochlea, is the most common otologic problem caused by aging and noise trauma. The cochlea, a delicate and complex biological mechanosensory transducer in the inner ear, has been extensively studied with the goal of improving diagnosis of SNHL. However, the difficulty associated with accessing the cochlea and resolving the microstructures that facilitate hearing within it in a minimally-invasive way has prevented us from being able to assess the pathology underlying SNHL in humans. To address this problem we investigated the ability of a multimodal optical system that combines optical coherence tomography (OCT) and single photon autofluorescence imaging (AFI) to enable visualization and evaluation of microstructures in the cochlea. A laboratory OCT/AFI imager was built to acquire high resolution OCT and single photon fluorescence images of the cochlea. The imager's ability to resolve diagnostically-relevant details was evaluated in ears extracted from normal and noise-exposed mice. A prototype endoscopic OCT/AFI imager was developed based on a double-clad fiber approach. Our measurements show that the multimodal OCT/AFI imager can be used to evaluate structural integrity in the mouse cochlea. Therefore, we believe that this technology is promising as a potential clinical evaluation tool, and as a technique for guiding otologic surgeries such as cochlear implant surgery.

  8. Middle fossa arachnoid cysts and inner ear symptoms: Are they related?

    Science.gov (United States)

    Proimos, E; Chimona, Ts; Memtsas, Z; Papadakis, Ce

    2014-04-01

    Arachnoid cysts most frequently occur in the middle cranial fossa and when they are symptomatic, patients present with central nervous symptoms. Nevertheless, a large proportion of arachnoid cysts are incidentally diagnosed during neuroimaging in cases with nonspecific symptoms. The cases of two males with middle cranial fossa arachnoid cysts with nonspecific inner ear symptoms were retrospectively reviewed. The first patient presented with mild headache, nausea, vertigo, unsteadiness, and tinnitus on the left ear while the second patient's main complaint was left sided tinnitus. Both patients (initially managed for peripheral disorders) underwent a thorough clinical and electrophysiological evaluation. Because of the patients' persistent clinical symptoms, and indications of CNS disorder in the first case, neuroimaging by brain MRI was performed revealing a middle cranial fossa arachnoid cyst in both patients. Occasionally, patients with arachnoid cysts may present with mild, atypical or intermittent and irrelevant symptoms which can mislead diagnosis. Otorhinolaryngologists should be aware of the fact that atypical, recurrent or intermittent symptoms may masquerade a CNS disorder. Hippokratia 2014; 18 (2):168-171.

  9. Effect of Hypergravity on Carbonanhydrase Reactivity in inner Ear Ioncytes of developing Cichlid Fish

    Science.gov (United States)

    Beier, M.; Anken, R.; Rahmann, H.

    It has been shown earlier that hypergravity slows down inner ear otolith growth in developing fish. Otolith growth in terms of mineralisation mainly depends on the enzyme carboanhydrase (CAH), which is responsible for the provision of the pH- value necessary for calcium carbonate deposition and thus also is presumed to play a prominent role in Ménière's disease (a sensory - motor disorder inducing vertigo and kinetosis). Larval siblings of cichlid fish (Oreochromis mossambicus) were subjected to hypergravity (3g; 6 hours) during development and separated into normally and kinetotically swimming individuals following the transfer to 1g (i.e., stopping the centrifuge; kinetotically behaving fish performed spinning movements). Subsequently, CAH was histochemically demonstrated in inner ear ionocytes (cells involved in the endolymphatic ion exchange) and enzyme reactivity was determined densitometrically. The results showed that CAH-reactivity was significantly increased in normally behaving hyper-g specimens as compared to controls kept at 1g, whereas no difference in enzyme reactivity was evident between the controls and kinetotically behaving fish. On the background of earlier studies, according to which (1) hypergravity induces a decrease of otolith growth and (2) the otolithic calcium incorporation (visualized using the calcium -tracer alizarin complexone) of kinetotically swimming hyper - g fish was lower as compared to normally behaving hyper - g animals, the present study strongly supports the concept that an increase in CAH-reactivity may result in a decrease of otolithic calcium deposition. The mechanism regulating CAH-activity hitherto remains to be determined. Acknowledgement: This work was financially supported by the German Aerospace Center (DLR) (FKZ: 50 WB 9997).

  10. Application of insulin-like growth factor 1 in the treatment of inner ear disorders

    Directory of Open Access Journals (Sweden)

    Norio eYamamoto

    2014-09-01

    Full Text Available Sensorineural hearing loss is considered an intractable disease, given that hair and supporting cells of the postnatal mammalian cochlea are unable to regenerate. However, with progress in regenerative medicine in the 21st century, several innovative approaches for achieving regeneration of inner ear hair and supporting cells have become available. These methods include stem cell transplantation, overexpression of specific genes, and treatment with growth factors. Insulin-like growth factor 1 (IGF-1 is one of the growth factors that are involved in the development of the inner ear. Treatment with IGF-1 maintains hair cell numbers in the postnatal mammalian cochlea after various types of hair cell injuries, with activation of two major pathways downstream of IGF-1 signaling. In the aminoglycoside-treated neonatal mouse cochlear explant culture, promotion of the cell-cycle in supporting cells as well as inhibition of hair cell apoptosis was observed in the IGF-1-treated group. Activation of downstream molecules was observed in supporting cells and, in turn, supporting cells contribute to the maintenance of hair cell numbers. Using comprehensive analysis of the gene expression, the candidate effector molecules of the IGF-1 signaling pathway in the protection of hair cells were identified as Netrin1 and Gap43. Based on these studies, a clinical trial has sought to investigate the effects of IGF-1 on sensorineural hearing loss. Sudden sensorineural hearing loss that was refractory to systemic steroids was treated with IGF-1 in a gelatin hydrogel and the outcome was compared with a historical control of hyperbaric oxygen therapy. The proportion of patients showing hearing improvement was significantly higher in the IGF-1-treatment group at 24 weeks after treatment than in the control group. A randomized clinical trial is ongoing to compare the effect of IGF-1 treatment with that of intra-tympanic steroids for sudden sensorineural hearing loss that is

  11. HCN channels are not required for mechanotransduction in sensory hair cells of the mouse inner ear.

    Directory of Open Access Journals (Sweden)

    Geoffrey C Horwitz

    Full Text Available The molecular composition of the hair cell transduction channel has not been identified. Here we explore the novel hypothesis that hair cell transduction channels include HCN subunits. The HCN family of ion channels includes four members, HCN1-4. They were originally identified as the molecular correlates of the hyperpolarization-activated, cyclic nucleotide gated ion channels that carry currents known as If, IQ or Ih. However, based on recent evidence it has been suggested that HCN subunits may also be components of the elusive hair cell transduction channel. To investigate this hypothesis we examined expression of mRNA that encodes HCN1-4 in sensory epithelia of the mouse inner ear, immunolocalization of HCN subunits 1, 2 and 4, uptake of the transduction channel permeable dye, FM1-43 and electrophysiological measurement of mechanotransduction current. Dye uptake and transduction current were assayed in cochlear and vestibular hair cells of wildtype mice exposed to HCN channel blockers or a dominant-negative form of HCN2 that contained a pore mutation and in mutant mice that lacked HCN1, HCN2 or both. We found robust expression of HCNs 1, 2 and 4 but little evidence that localized HCN subunits in hair bundles, the site of mechanotransduction. Although high concentrations of the HCN antagonist, ZD7288, blocked 50-70% of the transduction current, we found no reduction of transduction current in either cochlear or vestibular hair cells of HCN1- or HCN2- deficient mice relative to wild-type mice. Furthermore, mice that lacked both HCN1 and HCN2 also had normal transduction currents. Lastly, we found that mice exposed to the dominant-negative mutant form of HCN2 had normal transduction currents as well. Taken together, the evidence suggests that HCN subunits are not required for mechanotransduction in hair cells of the mouse inner ear.

  12. Inflammasome activation in mouse inner ear in response to MCMV induced hearing loss

    Institute of Scientific and Technical Information of China (English)

    Xi Shi; Yanfen Dong; Ya Li; ZenLu Zhao; Huan Li; Shiwei Qiu; Yaohan Li; Weiwei Guo; Yuehua Qiao

    2015-01-01

    Objective:To identify presence of inflammasome activated in mouse cochlea with sensorineural hearing loss (SNHL) caused by cytomegalovirus (CMV) infection. Method:MCMV was injected into the right cerebral hemisphere in neonatal BALB/c mice at 2000 pfu virus titers. Auditory brainstem responses (ABRs) were tested to evaluate hearing at 21 days. Histopathological studies were conducted to confirm localizations of MCMV infected cells in the inner ear. Expression of inflammasome related factors was assessed by immunofluorescence, Quantitative real-time PCR and Western blotting. Results:In the mouse model of CMV induced SNHL, inflammasome related kinase Caspase-1 and downstream inflammatory factor IL-1b and IL-18 were found increased and activated after CMV infection in the cochlea. These factors could further up-regulate expression of IL-6 and TNF-a. These inflammatory factors are neurotoxicity and may contribute to hearing impairment. Furthermore, we also detected significantly increased AIM2 protein that accumulated in the SGN of cochleae with CMV infection. Significance:We have shown that inflammasome as a novel inherent immunity mechanism may contribute to hearing impairment. Conclusion:Our data indicate that imflammasome assemble in mouse inner ear in response to CMV infection. We have revealed a novel pa-thology event in CMV induced SNHL involving activation of inflammasome in mouse cochlea. Additionally, we have shown that inflammasome may be a novel target for prevention and treatment of CMV related SNHL. Copyright © 2016, The Authors. Production & hosting by Elsevier (Singapore) Pte Ltd On behalf of PLA General Hospital Department of OtolaryngologyHead and Neck Surgery. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

  13. Three dimensional and high resolution magnetic resonance imaging of the inner ear. Normal ears and anomaly scanned with 3D-CISS sequence

    Energy Technology Data Exchange (ETDEWEB)

    Edamatsu, Hideo [Dokkyo Univ., Saitama (Japan). Koshigaya Hospital; Uechi, Yoko; Honjyo, Shiro; Yamashita, Koichi; Tonami, Hisao

    1997-12-01

    The MRI system used in this study was a new scanning sequence, 3D-CISS (Three dimensional-constructive interference in steady state) with 1.5 Tesla. Ten normal ears and one ear with Mondini type anomaly were scanned and reconstructed. In imagings of normal inner ears, the cochlea has three spiral layers; basal, middle and apical turns. Each turn was separated into three parts; the scala vestibuli, osseous spiral lamina and scala tympani. Three semicircular ducts, utricle and saccule were also reconstructed in one frame. In the inner ear of Mondini anomaly, 3D MRI showed cochlear aplasia, hypoplasia of semicircular ducts and widely dilated vestibule. The imaging was identical with findings of ``common cavity``. The anomaly was easily recognized in 3D MRI more than in 2D imagings. The detailed and cubic imagings of the Mondini anomaly in 3D MRI could not be observed with conventional 2D MRI. 3D MRI is not invasive method and can scan a target very quickly. (author)

  14. Immunohistochemical localization of the Na-K-Cl co-transporter (NKCC1) in the gerbil inner ear.

    Science.gov (United States)

    Crouch, J J; Sakaguchi, N; Lytle, C; Schulte, B A

    1997-06-01

    We mapped the cellular and subcellular distribution of the Na-K-Cl co-transporter (NKCC) in the adult gerbil inner ear by immunostaining with a monoclonal antibody (MAb T4) generated against human colon NKCC. Heavy immunolabeling was seen in the basolateral plasma membrane of marginal cells in the stria vascularis and dark cells in the vestibular system. Subpopulations of fibrocytes in the cochlear spiral ligament and limbus and underlying the vestibular neurosensory epithelium also stained with moderate to strong intensity, apparently along their entire plasmalemma. Because MAb T4 recognizes both the basolateral secretory (NKCC1) and the apical absorptive (NKCC2) isoforms of the co-transporter, we employed reverse transcription and the polymerase chain reaction (RT-PCR) to explore isoform diversity in inner ear tissues. Using NKCC1 and NKCC2 isoform-specific PCR primers based on mouse and human sequences, only transcripts for NKCC1 were detected in the gerbil inner ear. The presence of abundant NKCC1 in the basolateral plasmalemma of strial marginal and vestibular dark cells confirms conclusions drawn from pharmacological and physiological data. The co-expression of NKCC1 and Na,K-ATPase in highly specialized subpopulations of cochlear and vestibular fibrocytes provides further evidence for their role in recycling K+ leaked or effluxed through hair cells into perilymph back to endolymph, as postulated in current models of inner ear ion homeostasis.

  15. Imaging of sensorineural hearing loss: a pattern-based approach to diseases of the inner ear and cerebellopontine angle

    NARCIS (Netherlands)

    Verbist, B.M.

    2012-01-01

    An overview is presented of the common and uncommon diseases of the inner ear and of the cochleovestibular nerve within the internal acoustic meatus and cerebellopontine angle cistern causing sensorineural deafness.An imaging-pattern-based approach is used to help detect disease and narrow the

  16. Aminoglycoside-induced hair cell death of inner ear organs causes functional deficits in adult zebrafish (Danio rerio.

    Directory of Open Access Journals (Sweden)

    Phillip M Uribe

    Full Text Available Aminoglycoside antibiotics, like gentamicin, kill inner ear sensory hair cells in a variety of species including chickens, mice, and humans. The zebrafish (Danio rerio has been used to study hair cell cytotoxicity in the lateral line organs of larval and adult animals. Little is known about whether aminoglycosides kill the hair cells within the inner ear of adult zebrafish. We report here the ototoxic effects of gentamicin on hair cells in the saccule, the putative hearing organ, and utricle of zebrafish. First, adult zebrafish received a single 30 mg/kg intraperitoneal injection of fluorescently-tagged gentamicin (GTTR to determine the distribution of gentamicin within inner ear sensory epithelia. After 4 hours, GTTR was observed in hair cells throughout the saccular and utriclar sensory epithelia. To assess the ototoxic effects of gentamicin, adult zebrafish received a single 250 mg/kg intraperitoneal injection of gentamicin and, 24 hours later, auditory evoked potential recordings (AEPs revealed significant shifts in auditory thresholds compared to untreated controls. Zebrafish were then euthanized, the inner ear fixed, and labeled for apoptotic cells (TUNEL reaction, and the stereociliary bundles of hair cells labeled with fluorescently-tagged phalloidin. Whole mounts of the saccule and utricle were imaged and cells counted. There were significantly more TUNEL-labeled cells found in both organs 4 hours after gentamicin injection compared to vehicle-injected controls. As expected, significantly fewer hair cell bundles were found along the rostral-caudal axis of the saccule and in the extrastriolar and striolar regions of the utricle in gentamicin-treated animals compared to untreated controls. Therefore, as in other species, gentamicin causes significant inner ear sensory hair cell death and auditory dysfunction in zebrafish.

  17. Orpheus 0 G or ear In microgravity to establish symptoms concomitant of inner and middle ear and osteoporosis in microgravity

    Science.gov (United States)

    Tomatis, Alfred; Talbi, Louisa; Vervoort, Jozef; Fromenteau, Joel; De Voigt, Martin; Van Deun, Jozef

    2005-08-01

    The goal of the proposed work is to collect data on the responses of the vestibular system to long-term conditions of weightlessness and to evaluate the benefits of a program of Electronic Ear(1) designed to act preventively to lessen symptoms due to weightlessness and to readapt the vestibular system after return to normal gravity.Data in the form of listening tests and brain maps tests(2) and observations(3) will be collected during pre- and post-flight simulation.We have to identify if the preservation process of astronauts against weightlessness effects is located in the ear. The long- term objective of the study is to create a blueprint of an Electronic Ear to be used on board should the outcome be positive.

  18. Safety of Repeated-Dose Intratympanic Injections with AM-101 in Acute Inner Ear Tinnitus.

    Science.gov (United States)

    Staecker, Hinrich; Morelock, Michael; Kramer, Timothy; Chrbolka, Pavel; Ahn, Joong Ho; Meyer, Thomas

    2017-09-01

    Objective To evaluate the safety and tolerability of repeated intratympanic administration of the gel-formulated NMDA receptor antagonist AM-101 in acute patients with inner ear tinnitus. Study Design Prospective, double-blind, randomized, placebo-controlled study. Setting Sixty-nine secondary and tertiary sites in North America, Europe, and Asia. Subjects and Methods In total, 343 subjects with persistent acute tinnitus after traumatic cochlear injury or otitis media were randomized to receive 3 intratympanic doses of either AM-101 0.87 mg/mL or placebo over 3 to 5 days. They were followed for 84 days. The primary safety end point was the incidence of a clinically meaningful hearing deterioration from baseline to study day 35. Further safety assessments included tympanic membrane closure rates, analysis of adverse events, hematology, blood chemistry, and vital signs. In addition, data were collected on applied anesthetics and injection techniques. Results The treatment was well tolerated, with no intervention-related serious adverse events. The incidence of clinically meaningful hearing deterioration was low, comparable between treatment groups ( P = .82 for the primary safety end point) and not different between treated and untreated ears in unilaterally treated subjects. The rate of treatment and procedure-related adverse events was similar among treatment groups. The tympanic membrane was closed in 92% of subjects within 1 week and in all subjects by study day 84. Blood values and vital signs were inconspicuous. Conclusion Repeated intratympanic injections of AM-101 over a 3- to 5-day period appear to be safe and well tolerated, demonstrating the ability to potentially use this delivery approach over longer time periods.

  19. The effect of dexamethasone/cell-penetrating peptide nanoparticles on gene delivery for inner ear therapy

    Directory of Open Access Journals (Sweden)

    Yoon JY

    2016-11-01

    Full Text Available Ji Young Yoon,1 Keum-Jin Yang,2 Shi-Nae Park,3 Dong-Kee Kim,3 Jong-Duk Kim1 1Department of Chemical and Biomolecular Engineering, BK 21 Plus Program, Korea Advanced Institute of Science and Technology, Guseong-Dong, Yuseong-Gu, Daejeon, 2Clinical Research Institute, St Mary’s Hospital, Daejeon, 3Department of Otolaryngology – Head and Neck Surgery, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea Abstract: Dexamethasone (Dex-loaded PHEA-g-C18-Arg8 (PCA nanoparticles (PCA/Dex were developed for the delivery of genes to determine the synergistic effect of Dex on gene expression. The cationic PCA nanoparticles were self-assembled to create cationic micelles containing an octadecylamine (C18 core with Dex and an arginine 8 (Arg8 peptide shell for electrostatic complexation with nucleic acids (connexin 26 [Cx26] siRNA, green fluorescent protein [GFP] DNA or brain-derived neurotrophic factor [BDNF] pDNA. The PCA/Dex nanoparticles conjugated with Arg8, a cell-penetrating peptide that enhances permeability through a round window membrane in the inner ear for gene delivery, exhibited high uptake efficiency in HEI-OC1 cells. This potential carrier co-delivering Dex and the gene into inner ear cells has a diameter of 120–140 nm and a zeta potential of 20–25 mV. Different types of genes were complexed with the Dex-loaded PCA nanoparticle (PCA/Dex/gene for gene expression to induce additional anti-inflammatory effects. PCA/Dex showed mildly increased expression of GFP and lower mRNA expression of inflammatory cytokines (IL1b, IL12, and INFr than did Dex-free PCA nanoparticles and Lipofectamine® reagent in HEI-OC1 cells. In addition, after loading Cx26 siRNA onto the surface of PCA/Dex, Cx26 gene expression was downregulated according to real-time polymerase chain reaction for 24 h, compared with that using Lipofectamine reagent. After loading BDNF DNA into PCA/Dex, increased expression of BDNF was observed for 30

  20. Clinical application value of magnetic resonance imaging inner ear hydrography%磁共振内耳水成像的临床应用价值

    Institute of Scientific and Technical Information of China (English)

    张文武; 李维; 傅伟琪; 周旭洋; 陈国栋

    2015-01-01

    目的:探讨磁共振(MRI)内耳水成像在内耳病变患者中的临床价值。方法对45例怀疑内耳病变患者,行磁共振内耳水成像扫描,并进行最大密度投影(MIP)、多平面重建(MPR)、容积重建(VR)后处理。结果45例患者均能清晰显示内耳结构,其中内耳畸形8例,结构正常37例。结论内耳水成像能清晰、立体的显示内耳膜迷路及内听道精细解剖结构,并显示其发育状况及通畅程度,能够为内耳病变患者的诊断和术前评估提供重要的影像学依据。%Objective To explore the clinical value of magnetic resonance imaging (MRI) inner ear hydrography in inner ear disease patients.Methods MRI inner ear hydrography was applied in 45 patients with suspected inner ear disease, with process of maximum intensity projection (MIP), multiplanar reconstruction (MRP), and volume reconstruction (VR).Results The inner ear anatomical structures were displayed clearly in all the 45 cases, and there were 8 cases with inner ear malformations and 37 cases with normal structure.Conclusion The magnetic resonance inner ear hydrography can not only clearly and stereoscopically show anatomical structure of inner ear membranous labyrinth and inner auditory canal, but also show their developmental situation and unobstructed degree. It can provide important imaging parameters for the diagnosis and preoperative assessment of patients with inner ear disease.

  1. Your Ears

    Science.gov (United States)

    ... gross and useful. continue The Middle Ear: Good Vibrations After sound waves enter the outer ear, they travel through the ... ear's main job is to take those sound waves and turn them into vibrations that are delivered to the inner ear. To ...

  2. The mechanism and site of action of lidocaine hydrochloride in guinea pig inner ear.

    Science.gov (United States)

    Laurikainen, E; Lin, X; Nuttall, A L; Dolan, D F

    1997-07-01

    Lidocaine was applied to the round window (RW) in order to localize its site of action in the cochlea. Cochlear microphonic (CM), summating potential (SP), and compound action potential (CAP) input/output functions were measured to a 16 kHz tone burst to assess the functional changes of the cochlea. In separate experiments, the effect of lidocaine on the whole cell current of isolated outer hair cells (OHC) was studied. A dose of 2 microliters of 40 mM lidocaine in saline solution, when applied to the RW, caused a small change in all measured variables, indicating a passage of the drug through the RW membrane to sites of action. However, 160 mM of lidocaine further decreased CM, SP, and CAP by a total of 40% from the control. A partial recovery occurred for CM during the 30 min follow-up period. CAP and SP continued to decline. In isolated OHCs, lidocaine decreased the whole cell current in a dose-dependent fashion. The KD for lidocaine effect on OHCs was 7 mM. Our in vivo results indicate that lidocaine affects OHCs and reduces CM, causing a subsequent reduction in SP and CAP. The increased effect of lidocaine on CAP and SP, while CM is recovering, suggests an additional specific effect of lidocaine on the cochlear nerve and/or on inner hair cells. Considering that lidocaine alters OHC current (in isolated hair cells) and that lidocaine does not affect endocochlear potential [Laurikainen et al. Acta Otolaryngol (Stockh) 1991: 112: 800-9], the observed CM changes are most likely due to an in vivo effect on OHCs. Thus, the early effect of lidocaine on the cochlea appears to be due to a significant change in organ of Corti function, rather than to direct anesthesia of the cochlear nerve. Later, an independent effect of the drug may occur on neural tissues in the inner ear.

  3. The connexin 30.3 of zebrafish homologue of human connexin 26 may play similar role in the inner ear.

    Science.gov (United States)

    Chang-Chien, Ju; Yen, Yung-Chang; Chien, Kuo-Hsuan; Li, Shaun-Yow; Hsu, Tsai-Ching; Yang, Jiann-Jou

    2014-07-01

    The intercellular gap junction channels formed by connexins (CXs) are important for recycling potassium ions in the inner ear. CXs are encoded by a family of the CX gene, such as GJB2, and the mechanism leading to mutant connexin-associated diseases, including hearing loss, remains to be elucidated. In this study, using bioinformatics, we found that two zebrafish cx genes, cx27.5 and cx30.3, are likely homologous to human and mouse GJB2. During embryogenesis, zebrafish cx27.5 was rarely expressed at 1.5-3 h post-fertilization (hpf), but a relatively high level of cx27.5 expression was detected from 6 to 96 hpf. However, zebrafish cx30.3 transcripts were hardly detected until 9 hpf. The temporal experiment was conducted in whole larvae. Both cx27.5 and cx30.3 transcripts were revealed significantly in the inner ear by reverse transcription polymerase chain reaction (RT-PCR) and whole-mount in situ hybridization (WISH). In the HeLa cell model, we found that zebrafish Cx27.5 was distributed intracellularly in the cytoplasm, whereas Cx30.3 was localized in the plasma membrane of HeLa cells stably expressing Cx proteins. The expression pattern of zebrafish Cx30.3 in HeLa cells was more similar to that of cells expressing human CX26 than Cx27.5. In addition, we found that Cx30.3 was localized in the cell membrane of hair cells within the inner ear by immunohistochemistry (IHC), suggesting that zebrafish cx30.3 might play an essential role in the development of the inner ear, in the same manner as human GJB2. We then performed morpholino knockdown studies in zebrafish embryos to elucidate the physiological functions of Cx30.3. The zebrafish cx30.3 morphants exhibited wild-type-like and heart edema phenotypes with smaller inner ears at 72 hpf. Based on these results, we suggest that the zebrafish Cx30.3 and mammalian CX26 may play alike roles in the inner ear. Thus, zebrafish can potentially serve as a model for studying hearing loss disorders that result from human CX

  4. 大鼠内耳胚胎和出生后的组织学研究(英)%Histological study on the embryonic and postnatal development of the in-ner ear of the mouse

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@The mouse labyrinth is an excellent model for study-ing the morphogenesis and cytodifferentiation of the mam-malian inner ear' s postnatal developmental periods andthe availability of numerous genetic mutants with a variety of inner ear abnormalities. There are many genes affectingthe inner ear of the mouse, and some of these lead to le-sions which resemble lesions occurring in man.

  5. Streptomycin action to the mammalian inner ear vestibular organs: comparison between pigmented guinea pigs and rats.

    Science.gov (United States)

    Meza, Graciela; Aguilar-Maldonado, Beatriz

    2007-01-01

    Streptomycin is the antibiotic of choice to treat tuberculosis and other infectious diseases but it causes vestibular malfunction and hipoacusia. Rodents are usually employed as models of drug action to the inner ear and results are extrapolated to what happens in humans. In rats, streptomycin destroys macular sensory cells and does not affect cochlear ones, whereas in guinea pigs the contrary is true. Action on the vestibular cristae cells involved in vestibulo-ocular reflex integrity is less clear. Thus, we compared this response in both pigmented guinea pigs (Cavia cobaya) and rats (Rattus norvegicus) after parallel streptomycin chronic treatment. In guinea pigs, the reflex was obliterated along treatment time; in rats this behavior was not observed, suggesting that the end organ target was diverse. In recent studies, streptidine, a streptomycin derivative found in the blood of humans and rats treated with streptomycin, was the actual ototoxic agent. The putative streptomycin vestibular organ target observed in humans corresponds with the guinea pig observations. Results observed in rats are controversial: streptidine did not cause any damage either to vestibular cristae nor auditory cells. We hypothesize differential drug metabolism and distribution and conclude that results in laboratory animals may not always be applicable in the human situation.

  6. Inner ear anomalies causing congenital sensorineural hearing loss: CT and MR imaging findings

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Hyun Sook; Paik, Sang Hyun; Cha, Jang Gyu; Park, Seong Jin; Joh, Joon Hee; Park, Jai Soung; Kim, Dae Ho; Lee, Hae Kyung; Kim, Shi Chan [Soonchunhyang University Bucheon Hospital, Buchon(Korea, Republic of)

    2005-07-15

    Many congenital dysplasias of the osseous labyrinth have been identified, and the differential diagnosis of these dysplasias is essential for delivering proper patient management. We retrospectively reviewed the computed tomography (CT) and magnetic resonance (MR) imaging findings of 20 children who had congenital sensorineural hearing loss. The children included cases of enlarged vestibular aqueduct and endolymphatic sac (n=8), aplasia of the semicircular canal (n=4), lateral semicircular canal-vestibule dysplasia (n=3), common cavity malformations with a large vestibule (n=1), cochlear hypoplasia (n=1), Mondini's dysplasia with large vestibular aqueduct (n=1), Mondini's dysplasia with a large vestibule (n=1), and small internal auditory canal (n=1). Six cases were unilateral. Nine cases had combined deformities, and nine cased had cochlear implants. CT was performed with a 1.0-mm thickness in the direct coronal and axial sections with using bone algorithms. MR was performed with a temporal 3D T2 FSE 10-mm scan and with routine brain images. We describe here the imaging features for the anomalies of the inner ear in patients suffering from congenital sensorineural hearing loss.

  7. Distribution of neurosensory progenitor pools during inner ear morphogenesis unveiled by cell lineage reconstruction

    Science.gov (United States)

    Dyballa, Sylvia; Savy, Thierry; Germann, Philipp; Mikula, Karol; Remesikova, Mariana; Špir, Róbert; Zecca, Andrea; Peyriéras, Nadine; Pujades, Cristina

    2017-01-01

    Reconstructing the lineage of cells is central to understanding how the wide diversity of cell types develops. Here, we provide the neurosensory lineage reconstruction of a complex sensory organ, the inner ear, by imaging zebrafish embryos in vivo over an extended timespan, combining cell tracing and cell fate marker expression over time. We deliver the first dynamic map of early neuronal and sensory progenitor pools in the whole otic vesicle. It highlights the remodeling of the neuronal progenitor domain upon neuroblast delamination, and reveals that the order and place of neuroblasts’ delamination from the otic epithelium prefigure their position within the SAG. Sensory and non-sensory domains harbor different proliferative activity contributing distinctly to the overall growth of the structure. Therefore, the otic vesicle case exemplifies a generic morphogenetic process where spatial and temporal cues regulate cell fate and functional organization of the rudiment of the definitive organ. DOI: http://dx.doi.org/10.7554/eLife.22268.001 PMID:28051766

  8. XIRP2, an Actin-Binding Protein Essential for Inner Ear Hair-Cell Stereocilia

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    Déborah I. Scheffer

    2015-03-01

    Full Text Available Hair cells of the inner ear are mechanoreceptors for hearing and balance, and proteins highly enriched in hair cells may have specific roles in the development and maintenance of the mechanotransduction apparatus. We identified XIRP2/mXinβ as an enriched protein likely to be essential for hair cells. We found that different isoforms of this protein are expressed and differentially located: short splice forms (also called XEPLIN are targeted more to stereocilia, whereas two long isoforms containing a XIN-repeat domain are in both stereocilia and cuticular plates. Mice lacking the Xirp2 gene developed normal stereocilia bundles, but these degenerated with time: stereocilia were lost and long membranous protrusions emanated from the nearby apical surfaces. At an ultrastructural level, the paracrystalline actin filaments became disorganized. XIRP2 is apparently involved in the maintenance of actin structures in stereocilia and cuticular plates of hair cells, and perhaps in other organs where it is expressed.

  9. A Partial Calcium-Free Linker Confers Flexibility to Inner-Ear Protocadherin-15.

    Science.gov (United States)

    Powers, Robert E; Gaudet, Rachelle; Sotomayor, Marcos

    2017-03-07

    Tip links of the inner ear are protein filaments essential for hearing and balance. Two atypical cadherins, cadherin-23 and protocadherin-15, interact in a Ca(2+)-dependent manner to form tip links. The largely unknown structure and mechanics of these proteins are integral to understanding how tip links pull on ion channels to initiate sensory perception. Protocadherin-15 has 11 extracellular cadherin (EC) repeats. Its EC3-4 linker lacks several of the canonical Ca(2+)-binding residues, and contains an aspartate-to-alanine polymorphism (D414A) under positive selection in East Asian populations. We present structures of protocadherin-15 EC3-5 featuring two Ca(2+)-binding linker regions: canonical EC4-5 linker binding three Ca(2+) ions, and non-canonical EC3-4 linker binding only two Ca(2+) ions. Our structures and biochemical assays reveal little difference between the D414 and D414A variants. Simulations predict that the partial Ca(2+)-free EC3-4 linker exhibits increased flexural flexibility without compromised mechanical strength, providing insight into the dynamics of tip links and other atypical cadherins.

  10. A Biomechanical Model of the Inner Ear: Numerical Simulation of the Caloric Test

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    Shuang Shen

    2013-01-01

    Full Text Available Whether two vertical semicircular canals can receive thermal stimuli remains controversial. This study examined the caloric response in the three semicircular canals to the clinical hot caloric test using the finite element method. The results of the developed model showed the horizontal canal (HC cupula maximally deflected to the utricle side by approximately 3 μm during the hot supine test. The anterior canal cupula began to receive the caloric stimuli about 20 s after the HC cupula, and it maximally deflected to the canal side by 0.55 μm. The posterior canal cupula did not receive caloric stimuli until approximately 40 s after the HC cupula, and it maximally deflected to the canal side by 0.34 μm. Although the endolymph flow and the cupular deformation change with respect to the head position during the test, the supine test ensures the maximal caloric response in the HC, but no substantial improvement for the responses of the two vertical canals was observed. In conclusion, while the usual supine test is the optimum test for evaluating the functions of the inner ear, more irrigation time is needed in order to effectively clinically examine the vertical canals.

  11. A biomechanical model of the inner ear: numerical simulation of the caloric test.

    Science.gov (United States)

    Shen, Shuang; Liu, Yingxi; Sun, Xiuzhen; Zhao, Wei; Su, Yingfeng; Yu, Shen; Liu, Wenlong

    2013-01-01

    Whether two vertical semicircular canals can receive thermal stimuli remains controversial. This study examined the caloric response in the three semicircular canals to the clinical hot caloric test using the finite element method. The results of the developed model showed the horizontal canal (HC) cupula maximally deflected to the utricle side by approximately 3 μm during the hot supine test. The anterior canal cupula began to receive the caloric stimuli about 20 s after the HC cupula, and it maximally deflected to the canal side by 0.55 μm. The posterior canal cupula did not receive caloric stimuli until approximately 40 s after the HC cupula, and it maximally deflected to the canal side by 0.34 μm. Although the endolymph flow and the cupular deformation change with respect to the head position during the test, the supine test ensures the maximal caloric response in the HC, but no substantial improvement for the responses of the two vertical canals was observed. In conclusion, while the usual supine test is the optimum test for evaluating the functions of the inner ear, more irrigation time is needed in order to effectively clinically examine the vertical canals.

  12. Fossil evidence on evolution of inner ear cochlea in Jurassic mammals.

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    Luo, Zhe-Xi; Ruf, Irina; Schultz, Julia A; Martin, Thomas

    2011-01-07

    The coiled cochlea is a key evolutionary innovation of modern therian mammals. We report that the Late Jurassic mammal Dryolestes, a relative to modern therians, has derived bony characteristics of therian-like innervation, but its uncoiled cochlear canal is less derived than the coiled cochlea of modern therians. This suggests a therian-like innervation evolved before the fully coiled cochlea in phylogeny. The embryogenesis of the cochlear nerve and ganglion in the inner ear of mice is now known to be patterned by neurogenic genes, which we hypothesize to have influenced the formation of the auditory nerve and its ganglion in Jurassic therian evolution, as shown by their osteological correlates in Dryolestes, and by the similar base-to-apex progression in morphogenesis of the ganglion in mice, and in transformation of its canal in phylogeny. The cochlear innervation in Dryolestes is the precursory condition in the curve-to-coil transformation of the cochlea in mammalian phylogeny. This provides the timing of the evolution, and where along the phylogeny the morphogenetic genes were co-opted into patterning the cochlear innervation, and the full coiling of the cochlea in modern therians.

  13. Ultrastructural aspects of otoliths and sensory epithelia of fish inner ear exposed to hypergravity

    Science.gov (United States)

    Ibsch, M.; Nindl, G.; Anken, R. H.; Körtje, K. H.; Rahmann, H.

    The present electron microscopical investigations were directed to the question, whether alterations in the gravitational force might induce structural changes in the morphology of otoliths or/and inner ear sensory epithelia of developing and adult swordtail fish (Xiphophorus helleri) that had been kept either under long-term moderate hypergravity (8 days; 3g) or under short-time extreme hypergravity (10 minutes up to 9g). The otoliths of adult and neonate swordtail fish were investigated by means of scanning electron microscopy (SEM). Macular epithelia of adult fish were examined both by SEM and transmission electron microscopy (TEM). The saccular otoliths (sagittae) of normally hatched adult fish revealed an enormous inter- (and even intra-; i.e. left vs. right) individual diversity in shape and size, whereas the otoliths of utricles (lapilli) and lagenae (asterisci) seemed to be more constant regarding morphological parameters. The structural diversity of juvenile otoliths was found to be less prominent as compared to the adults, differing from the latter regarding their peculiar crystalline morphology. Qualitative differences in the fine structure (SEM) of otoliths taken from adult and larval animals kept under 3g in comparison to 1g controls could not be observed. The SEM and TEM investigations of sensory epithelia also did not reveal any effects due to 3g stimulation. Even extreme hypergravity (more than 7g) for 10 minutes did not result in distinct pathological changes.

  14. Diverse expression patterns of LIM-homeodomain transcription factors (LIM-HDs) in mammalian inner ear development.

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    Huang, Mingqian; Sage, Cyrille; Li, Huawei; Xiang, Mengquig; Heller, Stefan; Chen, Zheng-Yi

    2008-11-01

    LIM-homeodomain transcription factors (LIM-HDs) are essential in tissue patterning and differentiation. But their expression patterns in the inner ear are largely unknown. Here we report on a study of twelve LIM-HDs, by their tempo-spatial patterns that imply distinct yet overlapping roles, in the developing mouse inner ear. Expression of Lmx1a and Isl1 begins in the otocyst stage, with Lmx1a exclusively in the non-sensory and Isl1 in the prosensory epithelia. The second wave of expression at E12.5 includes Lhx3, 5, 9, Isl2, and Lmx1b in the differentiating sensory epithelia with cellular specificities. With the exception of Lmx1a and Lhx3, all LIM-HDs are expressed in ganglion neurons. Expression of multiple LIM-HDs within a cell type suggests their redundant function.

  15. Studies on Auditory and Vestibular End Organs and Brain Stem Nuclei. [inner ear damage and hearing defects

    Science.gov (United States)

    Ades, H. W.

    1974-01-01

    Cats were exposed to tones of 125, 1000, 2000, and 4000 Hz at sound pressure levels in the range 120 to 157.5 db, and for durations of one hour (1000, 2000, 4000 Hz) or four hours (125 Hz). Pure tone audiograms were obtained for each animal before and after exposure. Cochleas of animals were examined by phase-contrast microscopy. Extent of inner ear damage and range of frequencies for which hearing loss occurred increased as exposure tone was decreased in frequency. For example, exposure to 4000 Hz produced damage in a restricted region of the cochlea and hearing loss for a relatively narrow range of frequencies; exposure to 125 Hz produced wide-spread inner ear damage and hearing loss throughout the frequency range 125 to 6000 Hz.

  16. Single-cell RNA-Seq resolves cellular complexity in sensory organs from the neonatal inner ear.

    Science.gov (United States)

    Burns, Joseph C; Kelly, Michael C; Hoa, Michael; Morell, Robert J; Kelley, Matthew W

    2015-10-15

    In the inner ear, cochlear and vestibular sensory epithelia utilize grossly similar cell types to transduce different stimuli: sound and acceleration. Each individual sensory epithelium is composed of highly heterogeneous populations of cells based on physiological and anatomical criteria. However, limited numbers of each cell type have impeded transcriptional characterization. Here we generated transcriptomes for 301 single cells from the utricular and cochlear sensory epithelia of newborn mice to circumvent this challenge. Cluster analysis indicates distinct profiles for each of the major sensory epithelial cell types, as well as less-distinct sub-populations. Asynchrony within utricles allows reconstruction of the temporal progression of cell-type-specific differentiation and suggests possible plasticity among cells at the sensory-nonsensory boundary. Comparisons of cell types from utricles and cochleae demonstrate divergence between auditory and vestibular cells, despite a common origin. These results provide significant insights into the developmental processes that form unique inner ear cell types.

  17. CD44 is a marker for the outer pillar cells in the early postnatal mouse inner ear.

    Science.gov (United States)

    Hertzano, Ronna; Puligilla, Chandrakala; Chan, Siaw-Lin; Timothy, Caroline; Depireux, Didier A; Ahmed, Zubair; Wolf, Jeffrey; Eisenman, David J; Friedman, Thomas B; Riazuddin, Sheikh; Kelley, Matthew W; Strome, Scott E

    2010-09-01

    Cluster of differentiation antigens (CD proteins) are classically used as immune cell markers. However, their expression within the inner ear is still largely undefined. In this study, we explored the possibility that specific CD proteins might be useful for defining inner ear cell populations. mRNA expression profiling of microdissected auditory and vestibular sensory epithelia revealed 107 CD genes as expressed in the early postnatal mouse inner ear. The expression of 68 CD genes was validated with real-time RT-PCR using RNA extracted from microdissected sensory epithelia of cochleae, utricles, saccules, and cristae of newborn mice. Specifically, CD44 was identified as preferentially expressed in the auditory sensory epithelium. Immunohistochemistry revealed that within the early postnatal organ of Corti, the expression of CD44 is restricted to outer pillar cells. In order to confirm and expand this finding, we characterized the expression of CD44 in two different strains of mice with loss- and gain-of-function mutations in Fgfr3 which encodes a receptor for FGF8 that is essential for pillar cell development. We found that the expression of CD44 is abolished from the immature pillar cells in homozygous Fgfr3 knockout mice. In contrast, both the outer pillar cells and the aberrant Deiters' cells in the Fgfr3 ( P244R/ ) (+) mice express CD44. The deafness phenotype segregating in DFNB51 families maps to a linkage interval that includes CD44. To study the potential role of CD44 in hearing, we characterized the auditory system of CD44 knockout mice and sequenced the entire open reading frame of CD44 of affected members of DFNB51 families. Our results suggest that CD44 does not underlie the deafness phenotype of the DFNB51 families. Finally, our study reveals multiple potential new cell type-specific markers in the mouse inner ear and identifies a new marker for outer pillar cells.

  18. The role of her4 in inner ear development and its relationship with proneural genes and Notch signalling.

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    Marija Radosevic

    Full Text Available The generation of sensory neurons and hair cells of the inner ear is under tight control. Different members of the Hairy and Enhancer of Split genes (HES are expressed in the inner ear, their full array of functions still not being disclosed. We have previously shown that zebrafish her9 acts as a patterning gene to restrict otic neurogenesis to an anterior domain. Here, we disclose the role of another her gene, her4, a zebrafish ortholog of Hes5 that is expressed in the neurogenic and sensory domains of the inner ear. The expression of her4 is highly dynamic and spatiotemporally regulated. We demonstrate by loss of function experiments that in the neurogenic domain her4 expression is under the regulation of neurogenin1 (neurog1 and the Notch pathway. Moreover, her4 participates in lateral inhibition during otic neurogenesis since her4 knockdown results in overproduction of the number of neurog1 and deltaB-positive otic neurons. In contrast, during sensorigenesis her4 is initially Notch-independent and induced by atoh1b in a broad prosensory domain. At later stages her4 expression becomes Notch-dependent in the future sensory domains but loss of her4 does not result in hair cell overproduction, suggesting that there other her genes can compensate its function.

  19. Diagnosis of ossicular deformities and inner ear anomalies by high resolution CT scanning of the temporal bone

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    Isono, Michio

    1988-04-01

    A comparative study was undertaken to determine the optimum slice thickness and slice gaps that can define the fine contour and continuity of the ossicles and the inner ear. Horizontal tomography was proved to be contributory enough to obtain the whole ossicular chains and the whole labyrinthine capsule. Comparison of 1.5 mm slice thickness / 1.5 mm slice gaps, 1.0 mm slice thickness / 1.0 mm slice gaps and 1.5 mm slice thickness / 1.0 mm slice gaps revealed that the last condition was optimal for demonstrating the ossicular chains, the first for the inner ear. A significant relationship was found between CT findings and surgical findings of ossicular chains in chronic otitis media and cholesteatoma. Radiological classification of the inner ear malformation, which was obtained by this method, were agenesis of the whole labyrinthine capsule, agenesis of the cochlea, slight protrusion of the cochlear growth, poor cochlear turning, agenesis of all the semicircular canals, anterior semicircular canals (s.c.) without posterior and lateral s.c., anterior s.c. without hypoplasia of posterior s.c. and aplasia of lateral s.c., and smallness of the vestibule. (author) 59 refs.

  20. Cupulin is a zona pellucida-like domain protein and major component of the cupula from the inner ear.

    Science.gov (United States)

    Dernedde, Jens; Weise, Christoph; Müller, Eva-Christina; Hagiwara, Akira; Bachmann, Sebastian; Suzuki, Mamoru; Reutter, Werner; Tauber, Rudolf; Scherer, Hans

    2014-01-01

    The extracellular membranes of the inner ear are essential constituents to maintain sensory functions, the cupula for sensing torsional movements of the head, the otoconial membrane for sensing linear movements and accelerations like gravity, and the tectorial membrane in the cochlea for hearing. So far a number of structural proteins have been described, but for the gelatinous cupula precise data are missing. Here, we describe for the first time a major proteinogenic component of the cupula structure with an apparent molecular mass of 45 kDa from salmon. Analyses of respective peptides revealed highly conserved amino-acid sequences with identity to zona pellucida-like domain proteins. Immunohistochemistry studies localized the protein in the ampulla of the inner ear from salmon and according to its anatomical appearance we identified this glycoprotein as Cupulin. Future research on structure and function of zona pellucida-like domain proteins will enhance our knowledge of inner ear diseases, like sudden loss of vestibular function and other disturbances.

  1. Cupulin is a zona pellucida-like domain protein and major component of the cupula from the inner ear.

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    Jens Dernedde

    Full Text Available The extracellular membranes of the inner ear are essential constituents to maintain sensory functions, the cupula for sensing torsional movements of the head, the otoconial membrane for sensing linear movements and accelerations like gravity, and the tectorial membrane in the cochlea for hearing. So far a number of structural proteins have been described, but for the gelatinous cupula precise data are missing. Here, we describe for the first time a major proteinogenic component of the cupula structure with an apparent molecular mass of 45 kDa from salmon. Analyses of respective peptides revealed highly conserved amino-acid sequences with identity to zona pellucida-like domain proteins. Immunohistochemistry studies localized the protein in the ampulla of the inner ear from salmon and according to its anatomical appearance we identified this glycoprotein as Cupulin. Future research on structure and function of zona pellucida-like domain proteins will enhance our knowledge of inner ear diseases, like sudden loss of vestibular function and other disturbances.

  2. Inner ear tissue preservation by rapid freezing: improving fixation by high-pressure freezing and hybrid methods.

    Science.gov (United States)

    Bullen, A; Taylor, R R; Kachar, B; Moores, C; Fleck, R A; Forge, A

    2014-09-01

    In the preservation of tissues in as 'close to life' state as possible, rapid freeze fixation has many benefits over conventional chemical fixation. One technique by which rapid freeze-fixation can be achieved, high pressure freezing (HPF), has been shown to enable ice crystal artefact-free freezing and tissue preservation to greater depths (more than 40 μm) than other quick-freezing methods. Despite increasingly becoming routine in electron microscopy, the use of HPF for the fixation of inner ear tissue has been limited. Assessment of the quality of preservation showed routine HPF techniques were suitable for preparation of inner ear tissues in a variety of species. Good preservation throughout the depth of sensory epithelia was achievable. Comparison to chemically fixed tissue indicated that fresh frozen preparations exhibited overall superior structural preservation of cells. However, HPF fixation caused characteristic artefacts in stereocilia that suggested poor quality freezing of the actin bundles. The hybrid technique of pre-fixation and high pressure freezing was shown to produce cellular preservation throughout the tissue, similar to that seen in HPF alone. Pre-fixation HPF produced consistent high quality preservation of stereociliary actin bundles. Optimising the preparation of samples with minimal artefact formation allows analysis of the links between ultrastructure and function in inner ear tissues. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  3. Pattern of hair cell loss and delayed peripheral neuron degeneration in inner ear by a high-dose intratympanic gentamicin

    Institute of Scientific and Technical Information of China (English)

    Jintao Yu; Dalian Ding; Fengjun Wang; Haiyan Jiang; Hong Sun; Richard Salvi

    2014-01-01

    To gain insights into the ototoxic effects of aminoglycoside antibiotics (AmAn) and delayed peripheral ganglion neuron death in the inner ear, experimental animal models were widely used with several different approaches including AmAn systemic injections, combination treat-ment of AmAn and diuretics, or local application of AmAn. In these approaches, systemic AmAn treatment alone usually causes incomplete damage to hair cells in the inner ear. Co-administration of diuretic and AmAn can completely destroy the cochlear hair cells, but it is impossible to damage the vestibular system. Only the approach of AmAn local application can selectively eliminate most sensory hair cells in the inner ear. Therefore, AmAn local application is more suitable for studies for complete hair cell destructions in cochlear and vestibular system and the following delayed peripheral ganglion neuron death. In current studies, guinea pigs were unilaterally treated with a high concentration of gentamicin (GM, 40 mg/ml) through the tympanic membrane into the middle ear cavity. Auditory functions and vestibular functions were measured before and after GM treatment. The loss of hair cells and delayed degeneration of ganglion neurons in both cochlear and vestibular system were quantified 30 days or 60 days after treatment. The results showed that both auditory and vestibular functions were completely abolished after GM treatment. The sensory hair cells were totally missing in the cochlea, and severely destroyed in vestibular end-organs. The delayed spiral ganglion neuron death 60 days after the deafening procedure was over 50%. However, no obvious pathological changes were observed in vestibular ganglion neurons 60 days post-treatment. These results indicated that a high concentration of gentamycin delivered to the middle ear cavity can destroy most sensory hair cells in the inner ear that subsequently causes the delayed spiral ganglion neuron degeneration. This model might be useful for studies

  4. Tinnitus and other auditory problems - occupational noise exposure below risk limits may cause inner ear dysfunction.

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    Ann-Cathrine Lindblad

    Full Text Available The aim of the investigation was to study if dysfunctions associated to the cochlea or its regulatory system can be found, and possibly explain hearing problems in subjects with normal or near-normal audiograms. The design was a prospective study of subjects recruited from the general population. The included subjects were persons with auditory problems who had normal, or near-normal, pure tone hearing thresholds, who could be included in one of three subgroups: teachers, Education; people working with music, Music; and people with moderate or negligible noise exposure, Other. A fourth group included people with poorer pure tone hearing thresholds and a history of severe occupational noise, Industry. Ntotal = 193. The following hearing tests were used: - pure tone audiometry with Békésy technique, - transient evoked otoacoustic emissions and distortion product otoacoustic emissions, without and with contralateral noise; - psychoacoustical modulation transfer function, - forward masking, - speech recognition in noise, - tinnitus matching. A questionnaire about occupations, noise exposure, stress/anxiety, muscular problems, medication, and heredity, was addressed to the participants. Forward masking results were significantly worse for Education and Industry than for the other groups, possibly associated to the inner hair cell area. Forward masking results were significantly correlated to louder matched tinnitus. For many subjects speech recognition in noise, left ear, did not increase in a normal way when the listening level was increased. Subjects hypersensitive to loud sound had significantly better speech recognition in noise at the lower test level than subjects not hypersensitive. Self-reported stress/anxiety was similar for all groups. In conclusion, hearing dysfunctions were found in subjects with tinnitus and other auditory problems, combined with normal or near-normal pure tone thresholds. The teachers, mostly regarded as a group

  5. Dissection of inner ear neuroepithelium in zebrafish%斑马鱼内耳感觉上皮分离术

    Institute of Scientific and Technical Information of China (English)

    田永胜; 张旭; 陈晓巍

    2012-01-01

    Objective To establish a model by using zebrafish for the inner ear development and disease research,to explore the possibility of complete dissection of inner ear neuroepithelium in zebrafish by surface preparation of inner ear maculae.Methods The inner ear samples of zebra fish were fixed followed by harvesting.After decalcified and dehydrated,the coronal cryosections were made at 3 μm thickness at -23℃ using cryostat,the hematoxylin and eosin staining and immnofluorescence and histochemistry staining were performed,the saccules,utricles and lagenaes were successfully obtained by fine dissection.The sensory maculae were mounted on glass and then were stained.Results After hematoxylin and eosin staining and immnofluorescence and histochemistry staining of cryosections,the sensory maculae of inner ear could be determined by otoliths.On the basis of distinguish of otoliths,the sensory maculae of inner ear could be finely dissected,the overall intergrity of the sensory maculae could be preserved completely.After immnofluorescence and histochemistry staining,intact epithelia with strong hair cell bundle staining could be seen.Conclusions The neuroepithelium hair cell examination of zebra fish can be entirely attained by surface preparation of inner ear maculae.%目的 探索斑马鱼内耳感觉上皮的分离方法,为采用斑马鱼作为内耳发育及疾病研究的动物模型提供技术手段.方法 取4个月龄斑马鱼进行内耳组织冰冻切片,HE染色确定内耳感觉囊斑部位,并行免疫荧光染色观察毛细胞纤毛.在解剖显微镜下将斑马鱼内耳椭圆囊、球囊及听壶完整分离,取出内耳感觉囊斑平铺于载玻片中,进行免疫荧光染色,观察内耳感觉囊斑铺片的形态结构.结果 冰冻切片证实斑马鱼内耳感觉上皮位于囊斑内,并与耳石相对应.以耳石为标志分离出完整的内耳感觉囊斑组织,铺片免疫荧光染色后可观察到内耳感觉上皮形态结构完整,毛细

  6. CaMK-II activation is essential for zebrafish inner ear development and acts through Delta-Notch signaling.

    Science.gov (United States)

    Rothschild, Sarah C; Lahvic, Jamie; Francescatto, Ludmila; McLeod, Jamie J A; Burgess, Shawn M; Tombes, Robert M

    2013-09-01

    Zebrafish inner ear development is characterized by the crystallization of otoliths onto immotile kinocilia that protrude from sensory "hair" cells. The stereotypical formation of these sensory structures is dependent on the expression of key patterning genes and on Ca2+ signals. One potential target of Ca2+ signaling in the inner ear is the type II Ca2+/calmodulin-dependent protein kinase (CaMK-II), which is preferentially activated in hair cells, with intense activation at the base of kinocilia. In zebrafish, CaMK-II is encoded by seven genes; the expression of one of these genes (camk2g1) is enriched in hair cells. The suppression of camk2g1 expression by antisense morpholino oligonucleotides or inhibition of CaMK-II activation by the pharmacological antagonist, KN-93, results in aberrant otolith formation without preventing cilia formation. In fact, CaMK-II suppression results in additional ciliated hair cells and altered levels of Delta-Notch signaling members. DeltaA and deltaD transcripts are increased and DeltaD protein accumulates in hair cells of CaMK-II morphants, indicative of defective recycling and/or exocytosis. Our findings indicate that CaMK-II plays a critical role in the developing ear, influencing cell differentiation through extranuclear effects on Delta-Notch signaling. Continued expression and activation of CaMK-II in maculae and cristae in older embryos suggests continued roles in auditory sensory maturation and transduction.

  7. A clinicopathological analysis of papillary endolymphatic sac tumor in inner ear

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    LIN Yu-jing

    2013-05-01

    Full Text Available Background Endolymphatic sac tumor (ELST is a rare tumor originating fromendolymphatic epithelium of inner ear. This tumor exhibits low-grade malignancy with benign histopathological appearance and clinically destructive behavior which occurs in the skull base and frequently invades the posterior petrous bone, the mastoid, semicircular canal, cerebellopontine angle structures and cranial nerve. The presence of intracranial ELST always makes the diagnosis challenge for clinicians and pathologists. Herein we describe a case of ELST in skull base. The clinicopathology of this tumor and its differential diagnosis are discussed. Methods The clinical manifestation of a patient with primary ELST occurring in right cerebellopontine angle was presented retrospectively. Resected mass was routinely paraffin-embedded and stained with hematoxylin and eosin. Dako EnVision immunohistochemical staining system was used to detect the tumor antigen expressions, including cytokeratin (CK, vimentin (Vim, epithelial membrane antigen (EMA, carcinoembryonic antigen (CEA, synaptophysin (Syn, chromogranin A (CgA, S-100 protein (S-100, glial fibrillary acidic protein (GFAP, thyroglobulin (TG, thyroid transcription factor-1 (TTF-1 and Ki-67. Results A 32-year-old male patient presented with 20-year history of progressive hearing loss. MRI scan revealed an expansile lytic lesion of the mastoid process of the right petrous bone, measuring 4.20 cm × 3.30 cm × 2.00 cm, occupied the right cerebellopontine angle with infiltration of surrounding dura mater. But the lesion did not break the dura mater and invade the brain parenchyma. Craniotomy was performed and the tumor was removed totally. Histological examination revealed a papillary, cystic or glandular architecture in mass. The papillary and glandular structures were lined by a single layer of flattened cuboidal-to-columnar cells. The stroma of the papillary fronds was richly vascularized and chronically inflamed. There

  8. Gap junctions in the inner ear: comparison of distribution patterns in different vertebrates and assessement of connexin composition in mammals.

    Science.gov (United States)

    Forge, Andrew; Becker, David; Casalotti, Stefano; Edwards, Jill; Marziano, Nerissa; Nevill, Graham

    2003-12-08

    The distribution and size of gap junctions (GJ) in the sensory epithelia of the inner ear have been examined in a reptile (gecko), birds (chicken and owl), and mammals (mouse, guinea pig, gerbil, and bat), and the connexin composition of GJs in the mammalian inner ear has been assessed. Freeze fracture revealed a common pattern of GJ distribution in auditory and vestibular sensory epithelia in the different vertebrate classes. In all these tissues, GJs are numerous, often occupying more than 25% of the plasma membrane area of supporting cells and sometimes composed of more than 100,000 channels. Screening for 12 members of the connexin family in the mammalian inner ear by RT-PCR, Western blotting, and immunohistochemistry revealed four connexin isotypes, cx26, cx30, cx31, and cx43, in the cochlea and three, cx26, cx30, and cx43, in the vestibular organs. With antibodies characterised for their specificity, cx26 and cx30 colocalised in supporting cells of the organ of Corti, in the basal cell region of the stria vascularis, and in type 1 fibrocytes of the spiral ligament. No other connexin was detected in these regions. Cx31 was localised among type 2 fibrocytes below the spiral prominence, a region where cx30 was not expressed and cx26 expression appeared to be low. Cx43 was detected only in the region of "tension fibrocytes" lining the inner aspect of the otic capsule. This suggests separate functional compartments in the cochlea. In addition to cx26 and cx30, cx43 was detected in supporting cells of the vestibular sensory epithelia. Where cx26 and cx30 were colocalised, double immunogold labelling of thin sections showed both cx26 and cx30 evenly distributed in individual GJ plaques, a pattern consistent with the presence of heteromeric connexons. Coimmunoprecipitation of cochlear membrane proteins solubilised with a procedure that preserves the oligomeric structure of connexons confirmed the presence of heteromeric cx26/cx30 connexons. Heteromeric cx26/cx30

  9. Infliximab has no apparent effect in the inner ear hearing function of patients with rheumatoid arthritis and ankylosing spondylitis.

    Science.gov (United States)

    Toktas, H; Okur, E; Dundar, U; Dikici, A; Kahveci, O K

    2014-01-01

    Animal studies suggest that tumor necrosis factor (TNF) alpha blockers may pass to the inner ear in adequate concentration. In this prospective study, we aimed to evaluate the effect of infliximab on the inner ear hearing function in patients with ankylosing spondylitis (AS) and rheumatoid arthritis (RA). The patients with high disease activity, who were planned to begin infliximab for therapy by physical medicine and rehabilitation department, were referred to ear-nose-throat clinic for consultation. After physical and otoscopic examination, audiological tests were performed. Air conduction thresholds between 250 and 8,000 Hz, bone conduction thresholds between 500 and 4,000 Hz, pure tone average, speech discrimination scores, distortion product otoacoustic emission (DPOAE) were used to evaluate the hearing function. The tests were repeated 2 and 6 months after the initiation of the drug "infliximab." A total of 44 ears of 22 patients (17 males and 5 females) were evaluated. Fifteen patients had a diagnosis of AS, and seven patients had RA. After initiation of infliximab therapy, statistically significant improvement was observed in disease activity scores [Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) for AS, Disease Activity Score 28 (DAS-28) for RA] after 2 and 6 months (p  0.05). Any problem about the balance, vertigo, or dizziness was not reported from the patients during the treatment period. As a result, our study showed that there was no notable change or deterioration in the hearing function of the patients with AS and RA who were treated with infliximab. Further studies with higher number of patients with AS and RA and also with different TNF alpha inhibitors are needed to make more valid conclusion.

  10. Expression of polysialylated neural cell adhesion molecules on adult stem cells after neuronal differentiation of inner ear spiral ganglion neurons

    Energy Technology Data Exchange (ETDEWEB)

    Park, Kyoung Ho [Department of Otolaryngology Head and Neck Surgery, College of Medicine, Catholic University, Seoul (Korea, Republic of); Yeo, Sang Won, E-mail: swyeo@catholic.ac.kr [Department of Otolaryngology Head and Neck Surgery, College of Medicine, Catholic University, Seoul (Korea, Republic of); Troy, Frederic A., E-mail: fatroy@ucdavis.edu [Department of Biochemistry and Molecular Medicine, University of California, School of Medicine, Davis, CA 95616 (United States); Xiamen University, School of Medicine, Xiamen City (China)

    2014-10-17

    Highlights: • PolySia expressed on neurons primarily during early stages of neuronal development. • PolySia–NCAM is expressed on neural stem cells from adult guinea pig spiral ganglion. • PolySia is a biomarker that modulates neuronal differentiation in inner ear stem cells. - Abstract: During brain development, polysialylated (polySia) neural cell adhesion molecules (polySia–NCAMs) modulate cell–cell adhesive interactions involved in synaptogenesis, neural plasticity, myelination, and neural stem cell (NSC) proliferation and differentiation. Our findings show that polySia–NCAM is expressed on NSC isolated from adult guinea pig spiral ganglion (GPSG), and in neurons and Schwann cells after differentiation of the NSC with epidermal, glia, fibroblast growth factors (GFs) and neurotrophins. These differentiated cells were immunoreactive with mAb’s to polySia, NCAM, β-III tubulin, nestin, S-100 and stained with BrdU. NSC could regenerate and be differentiated into neurons and Schwann cells. We conclude: (1) polySia is expressed on NSC isolated from adult GPSG and on neurons and Schwann cells differentiated from these NSC; (2) polySia is expressed on neurons primarily during the early stage of neuronal development and is expressed on Schwann cells at points of cell–cell contact; (3) polySia is a functional biomarker that modulates neuronal differentiation in inner ear stem cells. These new findings suggest that replacement of defective cells in the inner ear of hearing impaired patients using adult spiral ganglion neurons may offer potential hope to improve the quality of life for patients with auditory dysfunction and impaired hearing disorders.

  11. Protective Roles of α-lipoic Acid in Rat Model of Mitochondrial DNA4834bp Deletion in Inner Ear

    Institute of Scientific and Technical Information of China (English)

    彭炜; 胡钰娟; 钟毅; 陈蓓; 孙宇; 杨阳; 孔维佳

    2010-01-01

    The protective roles of α-lipoic acid in the rat model of mitochondrial DNA (mtDNA) 4834bp deletion in inner ear were investigated. Forty female Wistar rats at 4 weeks of age were divided into four groups: group A (D-galactose group, n=10), group B (D-galactose+α-lipoic acid group, n=10), group C (α-lipoic acid group, n=10), and group D (control group, n=10). Auditory brainstem response (ABR) was used to detect the hearing threshold. Colorimetry was used to analyze activity of superoxide dismutase (SOD) and...

  12. Drugs affecting the inner ear. A review of their clinical efficacy, mechanisms of action, toxicity, and place in therapy.

    Science.gov (United States)

    Norris, C H

    1988-12-01

    Many drugs have a site of action within the inner ear. The list includes therapeutic, diagnostic and ototoxic agents. Therapeutic agents are most useful in cases of infections, endolymphatic hydrops, vascular insufficiency, vertigo of peripheral origin, autoimmune disease, otosclerosis (otospongiosis), sudden hearing loss and tinnitus. For infections, the most widely used anti-microbial agents are the penicillins and cephalosporins. There are no antiviral agents that have been proven useful for inner ear viral infections. However, steroids have been of some value for controlling some of the sequelae. Steroids have also been useful in conjunction with ampicillin in cases of syphilitic hearing loss. In cases of endolymphatic hydrops, the diuretics chlorthalidone, hydrochlorothiazide and acetazolamide have been useful. When diuretic and diet therapy cannot control endolymphatic hydrops, ototoxic drugs such as streptomycin have been used. In cases of vascular insufficiency within the inner ear, vasodilators such as carbon dioxide, papaverine, buphenine (nylidrin), naftidrofuryl (nafronyl) and thymoxamine have been recommended, but their true efficacy is questionable. Some success with betahistine has been achieved but the mechanism of this drug's action may be other than vasodilatation. Vertigo is best controlled with antihistamines and anticholinergics and with certain calcium channel blockers. Autoimmune inner ear disease appears to respond to a combination of steroids and cyclophosphamide. Although controversial, current pharmacotherapy for otosclerosis includes sodium fluoride. Sudden hearing loss is treated with a 'shotgun' combination of drugs and/or bed rest. There are as yet no drugs which can be used to routinely reduce tinnitus although some medications may help the patient tolerate the problem. Lignocaine (lidocaine) is useful in diagnosing, and very evanescently reducing, tinnitus. Glycerin (glycerol) is useful in diagnosing endolymphatic hydrops and may at

  13. Cellular Mechanism of Inner Ear Genetic Disease, roles of Kv7.1 (KCNQ1) Channel

    Science.gov (United States)

    Mousavi Nik, Atefeh

    Potassium channels are the most diverse and widely distributed membrane protein in all living organisms. They have various roles in the body such as controlling membrane potential, cell volume, and cell migration. Many studies have shown that mutation in these channels is associated with different diseases for example: Hearing Defect, Cardiac Arrhythmia, Episodic Ataxia, Seizure and Neuromyotonia. One of the most important diseases associated with K+ channel mutations is called Jervell and Lange-Nielsen syndrome (JLNS). This disease causes bilateral congenital deafness and the patients also suffer from Long QT and they usually experience syncopal episodes in their life and eventually die as a result of cardiac arrest. The gene KCNQ1 encodes the Kv7.1 voltage gated potassium channel. This channel expresses in apical membrane of marginal cell in stria vasularis of cochlea and secret K+ ion to endolymp to keep the endocochlear potential stable, which is necessary for the inner ear to function properly. Kv7.1 channel also expresses in cardiac myocytes and mutation in this gene is associated with another syndrome called Romano-Ward syndrome (RWS). Although Romano-Ward patients have mutation in KCNQ1, similar to Jervell and Lange-Nielsen patients, they only suffer from cardiac defect, and their hearing is completely normal. Several studies identified that mutations in Kv7.1 gene is associated with JLNS and RWS, but the biophysical and cellular mechanisms of these mutations are still unknown. To determine the cellular mechanisms of JLNS and RWS, and to provide mechanistic insight on the functional outputs of JLNS versus RWS mutations, we generated several mutant forms of the human Kv7.1 ( KCNQ1) clone, using site-directed mutagenesis to define their sub-cellular localization and examined their electrophysiological properties. We identified JLNS and RWS mutations at the S4-S5-linker, the pore loop (P-loop) and the C-terminus of hKv7.1 which have been found to control

  14. Cell type-specific transcriptome analysis reveals a major role for Zeb1 and miR-200b in mouse inner ear morphogenesis.

    Directory of Open Access Journals (Sweden)

    Ronna Hertzano

    2011-09-01

    Full Text Available Cellular heterogeneity hinders the extraction of functionally significant results and inference of regulatory networks from wide-scale expression profiles of complex mammalian organs. The mammalian inner ear consists of the auditory and vestibular systems that are each composed of hair cells, supporting cells, neurons, mesenchymal cells, other epithelial cells, and blood vessels. We developed a novel protocol to sort auditory and vestibular tissues of newborn mouse inner ears into their major cellular components. Transcriptome profiling of the sorted cells identified cell type-specific expression clusters. Computational analysis detected transcription factors and microRNAs that play key roles in determining cell identity in the inner ear. Specifically, our analysis revealed the role of the Zeb1/miR-200b pathway in establishing epithelial and mesenchymal identity in the inner ear. Furthermore, we detected a misregulation of the ZEB1 pathway in the inner ear of Twirler mice, which manifest, among other phenotypes, malformations of the auditory and vestibular labyrinth. The association of misregulation of the ZEB1/miR-200b pathway with auditory and vestibular defects in the Twirler mutant mice uncovers a novel mechanism underlying deafness and balance disorders. Our approach can be employed to decipher additional complex regulatory networks underlying other hearing and balance mouse mutants.

  15. In vitro and in vivo evaluation of a hydrogel reservoir as a continuous drug delivery system for inner ear treatment.

    Science.gov (United States)

    Hütten, Mareike; Dhanasingh, Anandhan; Hessler, Roland; Stöver, Timo; Esser, Karl-Heinz; Möller, Martin; Lenarz, Thomas; Jolly, Claude; Groll, Jürgen; Scheper, Verena

    2014-01-01

    Fibrous tissue growth and loss of residual hearing after cochlear implantation can be reduced by application of the glucocorticoid dexamethasone-21-phosphate-disodium-salt (DEX). To date, sustained delivery of this agent to the cochlea using a number of pharmaceutical technologies has not been entirely successful. In this study we examine a novel way of continuous local drug application into the inner ear using a refillable hydrogel functionalized silicone reservoir. A PEG-based hydrogel made of reactive NCO-sP(EO-stat-PO) prepolymers was evaluated as a drug conveying and delivery system in vitro and in vivo. Encapsulating the free form hydrogel into a silicone tube with a small opening for the drug diffusion resulted in delayed drug release but unaffected diffusion of DEX through the gel compared to the free form hydrogel. Additionally, controlled DEX release over several weeks could be demonstrated using the hydrogel filled reservoir. Using a guinea-pig cochlear trauma model the reservoir delivery of DEX significantly protected residual hearing and reduced fibrosis. As well as being used as a device in its own right or in combination with cochlear implants, the hydrogel-filled reservoir represents a new drug delivery system that feasibly could be replenished with therapeutic agents to provide sustained treatment of the inner ear.

  16. In vitro and in vivo evaluation of a hydrogel reservoir as a continuous drug delivery system for inner ear treatment.

    Directory of Open Access Journals (Sweden)

    Mareike Hütten

    Full Text Available Fibrous tissue growth and loss of residual hearing after cochlear implantation can be reduced by application of the glucocorticoid dexamethasone-21-phosphate-disodium-salt (DEX. To date, sustained delivery of this agent to the cochlea using a number of pharmaceutical technologies has not been entirely successful. In this study we examine a novel way of continuous local drug application into the inner ear using a refillable hydrogel functionalized silicone reservoir. A PEG-based hydrogel made of reactive NCO-sP(EO-stat-PO prepolymers was evaluated as a drug conveying and delivery system in vitro and in vivo. Encapsulating the free form hydrogel into a silicone tube with a small opening for the drug diffusion resulted in delayed drug release but unaffected diffusion of DEX through the gel compared to the free form hydrogel. Additionally, controlled DEX release over several weeks could be demonstrated using the hydrogel filled reservoir. Using a guinea-pig cochlear trauma model the reservoir delivery of DEX significantly protected residual hearing and reduced fibrosis. As well as being used as a device in its own right or in combination with cochlear implants, the hydrogel-filled reservoir represents a new drug delivery system that feasibly could be replenished with therapeutic agents to provide sustained treatment of the inner ear.

  17. Gravity-dependent nystagmus and inner-ear dysfunction suggest anterior and posterior inferior cerebellar artery infarct.

    Science.gov (United States)

    Shaikh, Aasef G; Miller, Benjamin R; Sundararajan, Sophia; Katirji, Bashar

    2014-04-01

    Cerebellar lesions may present with gravity-dependent nystagmus, where the direction and velocity of the drifts change with alterations in head position. Two patients had acute onset of hearing loss, vertigo, oscillopsia, nausea, and vomiting. Examination revealed gravity-dependent nystagmus, unilateral hypoactive vestibulo-ocular reflex (VOR), and hearing loss ipsilateral to the VOR hypofunction. Traditionally, the hypoactive VOR and hearing loss suggest inner-ear dysfunction. Vertigo, nausea, vomiting, and nystagmus may suggest peripheral or central vestibulopathy. The gravity-dependent modulation of nystagmus, however, localizes to the posterior cerebellar vermis. Magnetic resonance imaging in our patients revealed acute cerebellar infarct affecting posterior cerebellar vermis, in the vascular distribution of the posterior inferior cerebellar artery (PICA). This lesion explains the gravity-dependent nystagmus, nausea, and vomiting. Acute onset of unilateral hearing loss and VOR hypofunction could be the manifestation of inner-ear ischemic injury secondary to the anterior inferior cerebellar artery (AICA) compromise. In cases of combined AICA and PICA infarction, the symptoms of peripheral vestibulopathy might masquerade the central vestibular syndrome and harbor a cerebellar stroke. However, the gravity-dependent nystagmus allows prompt identification of acute cerebellar infarct. Copyright © 2014 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  18. The sex-linked fidget mutation abolishes Brn4/Pou3f4 gene expression in the embryonic inner ear.

    Science.gov (United States)

    Phippard, D; Boyd, Y; Reed, V; Fisher, G; Masson, W K; Evans, E P; Saunders, J C; Crenshaw, E B

    2000-01-01

    We have demonstrated that the phenotype of the mouse mutant sex-linked fidget ( slf ) is caused by developmental malformations of the inner ear that result in hearing loss and vestibular dysfunction. Recently, pilot mapping experiments suggested that the mouse Brn4 / Pou3f4 gene co-segregated with the slf locus on the mouse X chromosome. These mapping data, in conjunction with the observation that the vertical head-shaking phenotype of slf mutants is identical to that observed in mice with a targeted deletion of the Brn4 gene, suggested that slf is a mutant allele of the Brn4 gene. In this paper, we have identified the nature of the slf mutation, and demonstrated that it is an X chromosomal inversion with one breakpoint close to Brn4. This inversion selectively eliminates the expression of the Brn4 gene in the developing inner ear, but not the neural tube. Finally, these results demonstrate that the slf mutation is a good mouse model for the most prevalent form of X-linked congenital deafness in man, which is associated with mutations in the human Brn4 ortholog, POU3F4.

  19. Expression of polysialylated neural cell adhesion molecules on adult stem cells after neuronal differentiation of inner ear spiral ganglion neurons.

    Science.gov (United States)

    Park, Kyoung Ho; Yeo, Sang Won; Troy, Frederic A

    2014-10-17

    During brain development, polysialylated (polySia) neural cell adhesion molecules (polySia-NCAMs) modulate cell-cell adhesive interactions involved in synaptogenesis, neural plasticity, myelination, and neural stem cell (NSC) proliferation and differentiation. Our findings show that polySia-NCAM is expressed on NSC isolated from adult guinea pig spiral ganglion (GPSG), and in neurons and Schwann cells after differentiation of the NSC with epidermal, glia, fibroblast growth factors (GFs) and neurotrophins. These differentiated cells were immunoreactive with mAb's to polySia, NCAM, β-III tubulin, nestin, S-100 and stained with BrdU. NSC could regenerate and be differentiated into neurons and Schwann cells. We conclude: (1) polySia is expressed on NSC isolated from adult GPSG and on neurons and Schwann cells differentiated from these NSC; (2) polySia is expressed on neurons primarily during the early stage of neuronal development and is expressed on Schwann cells at points of cell-cell contact; (3) polySia is a functional biomarker that modulates neuronal differentiation in inner ear stem cells. These new findings suggest that replacement of defective cells in the inner ear of hearing impaired patients using adult spiral ganglion neurons may offer potential hope to improve the quality of life for patients with auditory dysfunction and impaired hearing disorders. Crown Copyright © 2014. Published by Elsevier Inc. All rights reserved.

  20. LKB1 Is Required for the Development and Maintenance of Stereocilia in Inner Ear Hair Cells in Mice.

    Directory of Open Access Journals (Sweden)

    Yuqin Men

    Full Text Available The LKB1 gene, which encodes a serine/threonine kinase, was discovered to play crucial roles in cell differentiation, proliferation, and the establishment of cell polarity. In our study, LKB1 conditional knockout mice (Atoh1-LKB1-/- mice were generated to investigate LKB1 function in the inner ear. Tests of auditory brainstem response and distortion product otoacoustic emissions revealed significant decreases in the hearing sensitivities of the Atoh1-LKB1-/- mice. In Atoh1-LKB1-/- mice, malformations of hair cell stereocilliary bundles were present as early as postnatal day 1 (P1, a time long before the maturation of the hair cell bundles. In addition, we also observed outer hair cell (OHC loss starting at P14. The impaired stereocilliary bundles occurred long before the presence of hair cell loss. Stereociliary cytoskeletal structure depends on the core actin-based cytoskeleton and several actin-binding proteins. By Western blot, we examined actin-binding proteins, specifically ERM (ezrin/radixin/moesin proteins involved in the regulation of the actin cytoskeleton of hair cell stereocilia. Our results revealed that the phosphorylation of ERM proteins (pERM was significantly decreased in mutant mice. Thus, we propose that the decreased pERM may be a key factor for the impaired stereocillia function, and the damaged stereocillia may induce hair cell loss and hearing impairments. Taken together, our data indicates that LKB1 is required for the development and maintenance of stereocilia in the inner ear.

  1. Planar cell polarity in the inner ear: how do hair cells acquire their oriented structure?

    Science.gov (United States)

    Lewis, Julian; Davies, Alex

    2002-11-05

    Sensory hair cells in the ear and lateral line have an asymmetrical hair-bundle structure, essential for their function as directional mechanotransducers. We examine four questions: (1) how does the planar asymmetry of the individual hair cell originate? (2) How are the orientations of neighboring hair cells coordinated? (3) How is the orientation of a group of hair cells controlled in relation to the ear as a whole? (4) How does the initial cell asymmetry lead to creation of the asymmetrical hair bundle? Studies of the development of hairs and bristles in Drosophila, combined with genetic data from vertebrates, suggest that the answer to questions (1) and (2) lies in asymmetries that develop at the cell cortex and at cell-cell junctions, generated by products of a set of primary planar cell polarity genes, including the transmembrane receptor Frizzled. A separate and largely independent mechanism controls asymmmetric allocation of cell fate determinants such as Numb at mitosis, in Drosophila and possibly in the ear also. Little is known about long-range signals that might orient hair cells globally in the ear, but progress has been made in identifying a set of genes responsible for read-out of the primary polarity specification. These genes, in flies and vertebrates, provide a link to assembly of the polarized cytoskeleton; myosin VIIA appears to belong in this group. The mechanism creating the staircase pattern of stereocilium lengths is unknown, but could involve regulation of stereocilium growth by Ca(2+) ions entering via transduction channels.

  2. Finite element modelling of sound transmission from outer to inner ear.

    Science.gov (United States)

    Areias, Bruno; Santos, Carla; Natal Jorge, Renato M; Gentil, Fernanda; Parente, Marco Pl

    2016-11-01

    The ear is one of the most complex organs in the human body. Sound is a sequence of pressure waves, which propagates through a compressible media such as air. The pinna concentrates the sound waves into the external auditory meatus. In this canal, the sound is conducted to the tympanic membrane. The tympanic membrane transforms the pressure variations into mechanical displacements, which are then transmitted to the ossicles. The vibration of the stapes footplate creates pressure waves in the fluid inside the cochlea; these pressure waves stimulate the hair cells, generating electrical signals which are sent to the brain through the cochlear nerve, where they are decoded. In this work, a three-dimensional finite element model of the human ear is developed. The model incorporates the tympanic membrane, ossicular bones, part of temporal bone (external auditory meatus and tympanic cavity), middle ear ligaments and tendons, cochlear fluid, skin, ear cartilage, jaw and the air in external auditory meatus and tympanic cavity. Using the finite element method, the magnitude and the phase angle of the umbo and stapes footplate displacement are calculated. Two slightly different models are used: one model takes into consideration the presence of air in the external auditory meatus while the other does not. The middle ear sound transfer function is determined for a stimulus of 60 dB SPL, applied to the outer surface of the air in the external auditory meatus. The obtained results are compared with previously published data in the literature. This study highlights the importance of external auditory meatus in the sound transmission. The pressure gain is calculated for the external auditory meatus.

  3. Travel Inside the Ear

    Science.gov (United States)

    ... Home » Health Info » Hearing, Ear Infections, and Deafness Travel Inside the Ear Video When sound waves reach ... are smaller than an orange seed. It then travels into the inner ear, which is filled with ...

  4. Safe Inner Ear Gas Tensions for Switch from Helium to Air Breathing During Decompression

    Science.gov (United States)

    2013-04-01

    interviewed, guided using a brief questionnaire including questions regarding vision or hearing changes. Sixty minutes after the divers reached the air...ear squeeze and could not complete the descent. In two cases, the un-afflicted divers were able to continue, but in three cases the dive was aborted ...for the afflicted and un-afflicted divers. Overall, 14 man-dives were aborted , none of which are included in the 104 man-dives completed. 6

  5. The braincase of the basal sauropod dinosaur Spinophorosaurus and 3D reconstructions of the cranial endocast and inner ear.

    Directory of Open Access Journals (Sweden)

    Fabien Knoll

    Full Text Available BACKGROUND: Sauropod dinosaurs were the largest animals ever to walk on land, and, as a result, the evolution of their remarkable adaptations has been of great interest. The braincase is of particular interest because it houses the brain and inner ear. However, only a few studies of these structures in sauropods are available to date. Because of the phylogenetic position of Spinophorosaurus nigerensis as a basal eusauropod, the braincase has the potential to provide key evidence on the evolutionary transition relative to other dinosaurs. METHODOLOGY/PRINCIPAL FINDINGS: The only known braincase of Spinophorosaurus ('Argiles de l'Irhazer', Irhazer Group; Agadez region, Niger differs significantly from those of the Jurassic sauropods examined, except potentially for Atlasaurus imelakei (Tilougguit Formation, Morocco. The basisphenoids of Spinophorosaurus and Atlasaurus bear basipterygoid processes that are comparable in being directed strongly caudally. The Spinophorosaurus specimen was CT scanned, and 3D renderings of the cranial endocast and inner-ear system were generated. The endocast resembles that of most other sauropods in having well-marked pontine and cerebral flexures, a large and oblong pituitary fossa, and in having the brain structure obscured by the former existence of relatively thick meninges and dural venous sinuses. The labyrinth is characterized by long and proportionally slender semicircular canals. This condition recalls, in particular, that of the basal non-sauropod sauropodomorph Massospondylus and the basal titanosauriform Giraffatitan. CONCLUSIONS/SIGNIFICANCE: Spinophorosaurus has a moderately derived paleoneuroanatomical pattern. In contrast to what might be expected early within a lineage leading to plant-eating graviportal quadrupeds, Spinophorosaurus and other (but not all sauropodomorphs show no reduction of the vestibular apparatus of the inner ear. This character-state is possibly a primitive retention in

  6. β3-integrin is required for differentiation in OC-2 cells derived from mammalian embryonic inner ear

    Directory of Open Access Journals (Sweden)

    Brunetta Ivan

    2012-03-01

    Full Text Available Abstract Background The mammalian inner ear contains the organ of Corti which is responsible for the conversion of sound into neuronal signals. This specialised epithelial tissue is the product of a complex developmental process where a common precursor cell type differentiates into the sound transducing hair cells and the non-innervated supporting cells. We hypothesised that integrin proteins, which are involved in cell attachment to extracellular matrix proteins and cellular signalling, play a role in the differentiation process of the precursor inner ear epithelial cells. To test our hypothesis we have utilised a cell line (OC-2 derived from E13 embryonic immortomouse inner ears. In vitro, by switching the incubation temperature from 33°C to 39°C, the OC-2 cells can be induced to differentiate and express hair cells markers, such as Myosin VIIa. The OC-2 cells are thus a useful model system for testing mechanism of hair cells differentiation. Results We have identified 4 integrin subunits which are expressed in OC-2 cells: α6, αv, β1 and β3. Among these, the relative level of expression of the αv, β1 and β3 subunits increased in a time dependent manner when the cells were exposed to the differentiating temperature of 39°C, most notably so for β3 which was not detectable at 33°C. Treatment of fully differentiated OC-2 cells with siRNA against the four integrin subunits reduced the expression of not only the respective integrin proteins but also of the hair cell marker Myosin VIIa. Conversely over-expression of β3 was sufficient to induce the expression of Myosin VIIa at 33°C. Conclusions Our data demonstrate that modulation of integrin expression is associated with the differentiation process of the OC-2 cells. This suggests that the maturation of the organ of Corti, from where OC-2 cells are derived, may also depend on changes of gene expression associated with integrin expression.

  7. The Braincase of the Basal Sauropod Dinosaur Spinophorosaurus and 3D Reconstructions of the Cranial Endocast and Inner Ear

    Science.gov (United States)

    Knoll, Fabien; Witmer, Lawrence M.; Ortega, Francisco; Ridgely, Ryan C.; Schwarz-Wings, Daniela

    2012-01-01

    Background Sauropod dinosaurs were the largest animals ever to walk on land, and, as a result, the evolution of their remarkable adaptations has been of great interest. The braincase is of particular interest because it houses the brain and inner ear. However, only a few studies of these structures in sauropods are available to date. Because of the phylogenetic position of Spinophorosaurus nigerensis as a basal eusauropod, the braincase has the potential to provide key evidence on the evolutionary transition relative to other dinosaurs. Methodology/Principal Findings The only known braincase of Spinophorosaurus (‘Argiles de l'Irhazer’, Irhazer Group; Agadez region, Niger) differs significantly from those of the Jurassic sauropods examined, except potentially for Atlasaurus imelakei (Tilougguit Formation, Morocco). The basisphenoids of Spinophorosaurus and Atlasaurus bear basipterygoid processes that are comparable in being directed strongly caudally. The Spinophorosaurus specimen was CT scanned, and 3D renderings of the cranial endocast and inner-ear system were generated. The endocast resembles that of most other sauropods in having well-marked pontine and cerebral flexures, a large and oblong pituitary fossa, and in having the brain structure obscured by the former existence of relatively thick meninges and dural venous sinuses. The labyrinth is characterized by long and proportionally slender semicircular canals. This condition recalls, in particular, that of the basal non-sauropod sauropodomorph Massospondylus and the basal titanosauriform Giraffatitan. Conclusions/Significance Spinophorosaurus has a moderately derived paleoneuroanatomical pattern. In contrast to what might be expected early within a lineage leading to plant-eating graviportal quadrupeds, Spinophorosaurus and other (but not all) sauropodomorphs show no reduction of the vestibular apparatus of the inner ear. This character-state is possibly a primitive retention in Spinophorosaurus, but due

  8. The physics of hearing: fluid mechanics and the active process of the inner ear.

    Science.gov (United States)

    Reichenbach, Tobias; Hudspeth, A J

    2014-07-01

    Most sounds of interest consist of complex, time-dependent admixtures of tones of diverse frequencies and variable amplitudes. To detect and process these signals, the ear employs a highly nonlinear, adaptive, real-time spectral analyzer: the cochlea. Sound excites vibration of the eardrum and the three miniscule bones of the middle ear, the last of which acts as a piston to initiate oscillatory pressure changes within the liquid-filled chambers of the cochlea. The basilar membrane, an elastic band spiraling along the cochlea between two of these chambers, responds to these pressures by conducting a largely independent traveling wave for each frequency component of the input. Because the basilar membrane is graded in mass and stiffness along its length, however, each traveling wave grows in magnitude and decreases in wavelength until it peaks at a specific, frequency-dependent position: low frequencies propagate to the cochlear apex, whereas high frequencies culminate at the base. The oscillations of the basilar membrane deflect hair bundles, the mechanically sensitive organelles of the ear's sensory receptors, the hair cells. As mechanically sensitive ion channels open and close, each hair cell responds with an electrical signal that is chemically transmitted to an afferent nerve fiber and thence into the brain. In addition to transducing mechanical inputs, hair cells amplify them by two means. Channel gating endows a hair bundle with negative stiffness, an instability that interacts with the motor protein myosin-1c to produce a mechanical amplifier and oscillator. Acting through the piezoelectric membrane protein prestin, electrical responses also cause outer hair cells to elongate and shorten, thus pumping energy into the basilar membrane's movements. The two forms of motility constitute an active process that amplifies mechanical inputs, sharpens frequency discrimination, and confers a compressive nonlinearity on responsiveness. These features arise because the

  9. Molecular characterization and expression of maternally expressed gene 3 (Meg3/Gtl2) RNA in the mouse inner ear

    DEFF Research Database (Denmark)

    Manji, S.S.; Sørensen, Brita Singers; Klockars, T.;

    2006-01-01

    The pathways responsible for sound perception in the cochlea involve the coordinated and regulated expression of hundreds of genes. By using microarray analysis, we identified several transcripts enriched in the inner ear, including the maternally expressed gene 3 (Meg3/Gtl2), an imprinted...... noncoding RNA. Real-time PCR analysis demonstrated that Meg3/Gtl2 was highly expressed in the cochlea, brain, and eye. Molecular studies revealed the presence of several Meg3/Gtl2 RNA splice variants in the mouse cochlea, brain, and eye. In situ hybridizations showed intense Meg3/Gtl2 RNA staining...... in the nuclei of type I spiral ganglion cells and in cerebellum near the dorsal vestibular region of the cochlea. In embryonic mouse head sections, Meg3/Gtl2 RNA expression was observed in the otocyst, brain, eye, cartilage, connective tissue, and muscle. Meg3/Gtl2 RNA expression increased in the developing...

  10. Histology and synchrotron radiation-based microtomography of the inner ear in a molecularly confirmed case of CHARGE syndrome.

    Science.gov (United States)

    Glueckert, Rudolf; Rask-Andersen, Helge; Sergi, Consolato; Schmutzhard, Joachim; Mueller, Bert; Beckmann, Felix; Rittinger, Olaf; Hoefsloot, Lies H; Schrott-Fischer, Anneliese; Janecke, Andreas R

    2010-03-01

    CHARGE (Coloboma of the iris or retina, heart defects, atresia of the choanae, retardation of growth and/or development, genital anomalies, ear anomalies) syndrome (OMIM #214800) affects about 1 in 10,000 children and is most often caused by chromodomain helicase DNA-binding protein-7 (CHD7) mutations. Inner ear defects and vestibular abnormalities are particularly common. Specifically, semicircular canal (SCC) hypoplasia/aplasia and the presence of a Mondini malformation can be considered pathognomonic in the context of congenital malformations of the CHARGE syndrome. We obtained a temporal bone (TB) of a patient with CHARGE syndrome who died from bacteremia at 3 months of age. The clinical diagnosis was confirmed in the patient by direct DNA sequencing and the detection of a de novo, truncating CHD7 mutation, c.6169dup (p.R2057fs). We assessed changes of the TB and the degree of neural preservation, which may influence the potential benefit of cochlear implantation. The TB was analyzed using synchrotron radiation-based micro computed tomography, and by light microscopy. The vestibular partition consisted of a rudimentary vestibule with agenesis of the SCCs. The cochlea was hypoplastic with poor or deficient interscaling and shortened (Mondini dysplasia). The organ of Corti had near normal structure and innervation. Modiolus and Rosenthal's canal were hypoplastic with perikarya displaced along the axon bundles into the internal acoustic meatus, which may be explained by the arrest or limited migration and translocation of the cell nuclei into the cochlear tube during development.

  11. Calcium Gradients in the Fish inner Ear sensory Epithelium and otolithic Membrane: an Energy filtering Transmission electron Microscopy (EFTEM) Study

    Science.gov (United States)

    Ibsch, M.; Anken, R.; Rahmann, H.

    Inner ear otolith formation in fish is supposed to be performed by the molecular release of proteinacious precursor material from the sensory epithelia, followed by an undirected and diffuse precipitation of calcium carbonate (which is mainly responsible for the functionally important weight of otoliths). Previous experiments have shown, however, that otolith formation in terms of provision both of the protein matrix and of calcium is regulated by a (likely neuronal) feedback mechanism. This regulating mechanism effects a symmetrical crystallisation of the corresponding otoliths in the inner ears of both sides of the head, which is necessary for a correct graviperception and for maintenance of postural control; thus, asymmetrical otoliths can induce kinetoses (e.g., space motion sickness) both in human and fish. On the background of an obviously directed incorporation of calcium into otoliths, the site of origin of the otoliths's inorganic components such as calcium still remains obscure. Therefore, ultrastructural and element analytical investigations were undertaken to screen the calcium distribution within the macular epithelial region using fish as model system. Electron spectroscopic imaging (ESI) and electron energy loss spectra (EELS) revealed discrete calcium-precipitations in the extracellular space of the otolithic membrane as well as within the lumina of the epithelial sensory cells. The calcium particles were accumulated at the macular tight junctions and seemed to be distributed in an ascending intracellular and a descending extracellular gradient towards the otolith. Further distinct calcium containing crystals covered the peripheral proteinacious layer of the otolith. The remaining endolymphatic space of the otocyst was lacking calcium precipitates. Overall, the present results indicate that the apical region of the macular epithelium is involved in the controlled release of calcium. This finding is in complete agreement with a study using calcium

  12. RAF kinase activity regulates neuroepithelial cell proliferation and neuronal progenitor cell differentiation during early inner ear development.

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    Marta Magariños

    Full Text Available BACKGROUND: Early inner ear development requires the strict regulation of cell proliferation, survival, migration and differentiation, coordinated by the concerted action of extrinsic and intrinsic factors. Deregulation of these processes is associated with embryonic malformations and deafness. We have shown that insulin-like growth factor I (IGF-I plays a key role in embryonic and postnatal otic development by triggering the activation of intracellular lipid and protein kinases. RAF kinases are serine/threonine kinases that regulate the highly conserved RAS-RAF-MEK-ERK signaling cascade involved in transducing the signals from extracellular growth factors to the nucleus. However, the regulation of RAF kinase activity by growth factors during development is complex and still not fully understood. METHODOLOGY/PRINCIPAL FINDINGS: By using a combination of qRT-PCR, Western blotting, immunohistochemistry and in situ hybridization, we show that C-RAF and B-RAF are expressed during the early development of the chicken inner ear in specific spatiotemporal patterns. Moreover, later in development B-RAF expression is associated to hair cells in the sensory patches. Experiments in ex vivo cultures of otic vesicle explants demonstrate that the influence of IGF-I on proliferation but not survival depends on RAF kinase activating the MEK-ERK phosphorylation cascade. With the specific RAF inhibitor Sorafenib, we show that blocking RAF activity in organotypic cultures increases apoptosis and diminishes the rate of cell proliferation in the otic epithelia, as well as severely impairing neurogenesis of the acoustic-vestibular ganglion (AVG and neuron maturation. CONCLUSIONS/SIGNIFICANCE: We conclude that RAF kinase activity is essential to establish the balance between cell proliferation and death in neuroepithelial otic precursors, and for otic neuron differentiation and axonal growth at the AVG.

  13. Gfi1Cre mice have early onset progressive hearing loss and induce recombination in numerous inner ear non-hair cells

    Science.gov (United States)

    Matern, Maggie; Vijayakumar, Sarath; Margulies, Zachary; Milon, Beatrice; Song, Yang; Elkon, Ran; Zhang, Xiaoyu; Jones, Sherri M.; Hertzano, Ronna

    2017-01-01

    Studies of developmental and functional biology largely rely on conditional expression of genes in a cell type-specific manner. Therefore, the importance of specificity and lack of inherent phenotypes for Cre-driver animals cannot be overemphasized. The Gfi1Cre mouse is commonly used for conditional hair cell-specific gene deletion/reporter gene activation in the inner ear. Here, using immunofluorescence and flow cytometry, we show that the Gfi1Cre mice produce a pattern of recombination that is not strictly limited to hair cells within the inner ear. We observe a broad expression of Cre recombinase in the Gfi1Cre mouse neonatal inner ear, primarily in inner ear resident macrophages, which outnumber the hair cells. We further show that heterozygous Gfi1Cre mice exhibit an early onset progressive hearing loss as compared with their wild-type littermates. Importantly, vestibular function remains intact in heterozygotes up to 10 months, the latest time point tested. Finally, we detect minor, but statistically significant, changes in expression of hair cell-enriched transcripts in the Gfi1Cre heterozygous mice cochleae compared with their wild-type littermate controls. Given the broad use of the Gfi1Cre mice, both for gene deletion and reporter gene activation, these data are significant and necessary for proper planning and interpretation of experiments. PMID:28181545

  14. Three-dimensional reconstruction of the guinea pig inner ear, comparison of OPFOS and light microscopy, applications of 3D reconstruction

    NARCIS (Netherlands)

    Hofman, R.; Segenhout, J. M.; Wit, H. P.

    2009-01-01

    Three-dimensional (3D) reconstruction of anatomical structures can give additional insight into the morphology and function of these structures. We compare 3D reconstructions of the guinea pig inner ear, using light microscopy and orthogonal plane fluorescence optical sectioning microscopy. Applicat

  15. Reduced expression of Connexin26 and its DNA promoter hypermethylation in the inner ear of mimetic aging rats induced by d-galactose.

    Science.gov (United States)

    Wu, Xia; Wang, Yanjun; Sun, Yu; Chen, Sen; Zhang, Shuai; Shen, Ling; Huang, Xiang; Lin, Xi; Kong, Weijia

    2014-09-26

    Connexin26 (Cx26), one of the major protein subunits forming gap junctions (GJs), is important in maintaining homeostasis in the inner ear and normal hearing. Cx26 mutation is one of the most common causes for inherited nonsyndromic deafness, but the relationship between Cx26 and presbycusis is unknown. Our study aimed at exploring the expression and the aberrant methylation of the promoter region of Cx26 gene in the cochlea of inner ear mimetic aging rats. We applied a mimetic aging of inner ear rat model with mtDNA common deletion by d-gal injection for 8weeks. Real-time RT-PCR and Western blot of rat inner ear tissue indicated that the Cx26 expression decreased in the d-gal group. Further bisulfite sequencing analysis revealed that the methylation status of the promoter region of Cx26 gene in the d-gal group was higher than that in control group. These results indicated that the decrease of Cx26 expression might contribute to the development of presbycusis and the hypermethylation of promoter region of GJB2 might be associated with the Cx26 downregulation.

  16. A comparison of inner ear imaging features at different time points of sudden sensorineural hearing loss with three-dimensional fluid-attenuated inversion recovery magnetic resonance imaging.

    Science.gov (United States)

    Zhu, Honglei; Ou, Yongkang; Fu, Jia; Zhang, Ya; Xiong, Hao; Xu, Yaodong

    2015-10-01

    It has been reported that about half of patients with sudden sensorineural hearing loss (SSNHL) show high signals in the affected inner ear on three-dimensional, fluid-attenuated inversion recovery magnetic resonance imaging (3D-FLAIR MRI). These signals may reflect minor hemorrhage or an increased concentration of protein in the inner ear, which has passed through blood vessels with increased permeability. Our objective was to compare the positive ratio of the high signal in affected inner ears at different time points to determine the suitable imaging time point for 3D-FLAIR MRI in SSNHL. 3D-FLAIR MRI images were taken at three times, precontrast and approximately 10 min and 4 h after intravenous injection of a single dose of gadodiamide (Gd) (0.1 mmol/kg), in 46 patients with SNHL. We compared the positive findings of the high signals in the inner ear of patients with SNHL as well as the signal intensity ratio (SIR) between the affected cochleae and unaffected cochleae at three time points. The positive ratios of the high signals in the affected inner ear at the time points of precontrast and 10 min and 4 h after the intravenous Gd injection were 26.1, 32.6, and 41.3%, respectively. The high signal intensity ratios of affected inner ears at the three time points were 1.28, 1.31, and 1.48, respectively. The difference between the positive ratios precontrast and at 10 min after the intravenous Gd injection was statistically significant (P = 0.006); the differences between the positive ratios at 4 h after the intravenous Gd injection and precontrast and between the ratios at 4 h and 10 min after the intravenous Gd injection were not statistically significant. The time effects of the median value of SIR were not significant (P = 0.064). We do not recommend 4 h after intravenous Gd injection as a time point to image the inner ear in SNHL. We believe that imaging precontrast and at 10 min after the intravenous Gd injection are suitable time points.

  17. Characteristics of sensorineural hearing loss secondary to inner ear acoustic trauma

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    Spremo Slobodan

    2008-01-01

    Full Text Available INTRODUCTION Cochlear damage secondary to exposure to acoustic trauma is the consequence of the acoustic energy effects on the hearing cells in Korti's organ. OBJECTIVE The objective was to assess the correlation between the degree of sensorineural hearing loss and the type of audiogram registered in acoustic trauma exposed patients. METHOD We analyzed 262 audiograms of patients exposed to acoustic trauma in correlation to 146 audiograms of patients with cochlear damage and hearing loss not related to acoustic trauma. "A" group consisted of acoustic trauma cases, while "B" group incorporated cases with hearing loss secondary to cochlear ischaemia or degeneration. All audiograms were subdivided with regard to the mean hearing loss into three groups: mild (21-40 dB HL, moderate (41-60 dB HL and severe (over 60 dB HL hearing loss. Based on audiogram configuration five types of audiogram were defined: type 1 flat; type 2 hearing threshold slope at 2 kHz, type 3 hearing threshold slope at 4 kHz; type 4 hearing threshold notch at 2 kHz; type 5 notch at 4 kHz. RESULTS Mild hearing loss was recorded in 163 (62.2% ears in the acoustic trauma group, while in 78 (29.8% ears we established moderate hearing loss with the maximum threshold shift at frequencies ranging from 4 kHz to 8 kHz. The least frequent was profound hearing loss, obtained in 21 (8% audiograms in the acoustic trauma group. Characteristic audiogram configurations in the acoustic trauma patient group were: type 1 (N=66; 25.2%, type 2 (N=71; 27.1%, and type 3 (N=68; 25.9%. Audiogram configurations were significanly different in the acoustic trauma group in comparison to the cochlear ischaemia group of patients (p=0.0005. CONCLUSION Cochlear damage concomitant to acoustic trauma could be assessed by the audiogram configuration. Preserved hearing acuity at low and mild frequency range indicates the limited damage to the hearing cells in Korti's organ in the apical cochlear turn.

  18. Inner-ear morphology of the New Zealand kiwi (Apteryx mantelli) suggests high-frequency specialization.

    Science.gov (United States)

    Corfield, Jeremy R; Kubke, M Fabiana; Parsons, Stuart; Köppl, Christine

    2012-10-01

    The sensory systems of the New Zealand kiwi appear to be uniquely adapted to occupy a nocturnal ground-dwelling niche. In addition to well-developed tactile and olfactory systems, the auditory system shows specializations of the ear, which are maintained along the central nervous system. Here, we provide a detailed description of the auditory nerve, hair cells, and stereovillar bundle orientation of the hair cells in the North Island brown kiwi. The auditory nerve of the kiwi contained about 8,000 fibers. Using the number of hair cells and innervating nerve fibers to calculate a ratio of average innervation density showed that the afferent innervation ratio in kiwi was denser than in most other birds examined. The average diameters of cochlear afferent axons in kiwi showed the typical gradient across the tonotopic axis. The kiwi basilar papilla showed a clear differentiation of tall and short hair cells. The proportion of short hair cells was higher than in the emu and likely reflects a bias towards higher frequencies represented on the kiwi basilar papilla. The orientation of the stereovillar bundles in the kiwi basilar papilla showed a pattern similar to that in most other birds but was most similar to that of the emu. Overall, many features of the auditory nerve, hair cells, and stereovilli bundle orientation in the kiwi are typical of most birds examined. Some features of the kiwi auditory system do, however, support a high-frequency specialization, specifically the innervation density and generally small size of hair-cell somata, whereas others showed the presumed ancestral condition similar to that found in the emu.

  19. MR visualization of the inner ear structures: comparison of 1.5 Tesla and 3 Tesla images

    Energy Technology Data Exchange (ETDEWEB)

    Graf, H.; Schick, F. [Tuebingen Univ. (Germany). Sektion Experimentelle Radiologie; Claussen, C.D.; Seemann, M.D. [Tuebingen Univ. (Germany). Abt. fuer Radiologische Diagnostik

    2004-01-01

    Aim of the Study: To compare high resolution MRI examinations of inner ear structures at 1.5 T and at 3 T. Method: Temporal bones were measured bilaterally in 3 healthy volunteers in a 1.5 T and in a 3 T MR-scanner using the respective one channel head coil (quadrature detection) of the manufacturer. The same steady-state gradient echo sequence (3D-CISS) was employed at a voxel size of 0.4x0.4x0.4mm{sup 3}. The signal-to-noise ratio (SNR) was determined quantitatively. Results: An SNR of 8 could be achieved for the measurements at 3 T in 7:37 min. The SNR at 3 T was, on average, a factor of 1.34 higher than that at 1.5 T despite the fact that the excitation angle had to be drastically reduced ({alpha} = 42 instead of {alpha} = 70 at 1.5 T) due to the limit of the specific absorption rate (SAR). Discussion: The MR representation of the inner ear is clearly improved at 3 T. To obtain the same SNR at 1.5 T approximately the double measuring time would be required, connected with reduced patient comfort and an increased risk for a displacement of the head during the high resolution measurement. (orig.) [German] Ziel der Studie: Vergleich der hochaufloesenden MR-Bildgebung der Innenohrstrukturen bei 1,5 T und 3 T. Methode: Es wurden jeweils beide Felsenbeine von 3 freiwilligen, gehoergesunden Probanden an einem 1,5 T und einem 3 T MR-Tomographen mit einer einkanaligen Quadratur-Kopfspule des Herstellers gemessen. An beiden Tomographen wurde dieselbe Steady-State Gradientenecho-Sequenz (3D-CISS) bei einer Voxelgroesse von 0,4x0,4x0,4mm{sup 3} verwendet. Das erhaltene Signal-Rausch-Verhaeltnis (SNR) wurde quantitativ ermittelt. Ergebnis: Ein SNR von 8 wurde fuer die Messungen bei 3 T in 7:37 min erreicht. Der SNR-Wert bei 3 T uebertraf den Wert bei 1,5 T um durchschnittlich das 1,34-fache, obwohl aufgrund der Begrenzung in der spezifischen Absorptionsrate (SAR) nur mit deutlich reduziertem Anregewinkel ({alpha} = 42 anstatt {alpha} = 70 bei 1,5 T) gearbeitet werden konnte

  20. Computed tomography findings of a patient with severe dysplasia of the inner ear and recurrent meningitis: a case report of gusher ear in a five-year old boy.

    Science.gov (United States)

    Alizadeh, Houman; Nasri, Fatemeh; Mehdizadeh, Mehrzad; Jamsa, Shahin

    2014-08-01

    Communication between subarachnoid and perlymphatic spaces can be due to a deficiency of lamina cribrosa (stapes gusher). Recognition of the condition may alter the course of treatment that can avoid perilymph gushing. A five-year-old boy presented with a history of congenital hearing loss and recurrent meningitis. The computed tomography (CT) of the temporal bone showed severe bilateral dysplasia in the inner ears in favor of gusher disease.

  1. Role of somatostatin receptor-2 in gentamicin-induced auditory hair cell loss in the Mammalian inner ear.

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    Yves Brand

    Full Text Available Hair cells and spiral ganglion neurons of the mammalian auditory system do not regenerate, and their loss leads to irreversible hearing loss. Aminoglycosides induce auditory hair cell death in vitro, and evidence suggests that phosphatidylinositol-3-kinase/Akt signaling opposes gentamicin toxicity via its downstream target, the protein kinase Akt. We previously demonstrated that somatostatin-a peptide with hormone/neurotransmitter properties-can protect hair cells from gentamicin-induced hair cell death in vitro, and that somatostatin receptors are expressed in the mammalian inner ear. However, it remains unknown how this protective effect is mediated. In the present study, we show a highly significant protective effect of octreotide (a drug that mimics and is more potent than somatostatin on gentamicin-induced hair cell death, and increased Akt phosphorylation in octreotide-treated organ of Corti explants in vitro. Moreover, we demonstrate that somatostatin receptor-1 knockout mice overexpress somatostatin receptor-2 in the organ of Corti, and are less susceptible to gentamicin-induced hair cell loss than wild-type or somatostatin-1/somatostatin-2 double-knockout mice. Finally, we show that octreotide affects auditory hair cells, enhances spiral ganglion neurite number, and decreases spiral ganglion neurite length.

  2. TMC1 and TMC2 Localize at the Site of Mechanotransduction in Mammalian Inner Ear Hair Cell Stereocilia

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    Kiyoto Kurima

    2015-09-01

    Full Text Available Mechanosensitive ion channels at stereocilia tips mediate mechanoelectrical transduction (MET in inner ear sensory hair cells. Transmembrane channel-like 1 and 2 (TMC1 and TMC2 are essential for MET and are hypothesized to be components of the MET complex, but evidence for their predicted spatiotemporal localization in stereocilia is lacking. Here, we determine the stereocilia localization of the TMC proteins in mice expressing TMC1-mCherry and TMC2-AcGFP. Functionality of the tagged proteins was verified by transgenic rescue of MET currents and hearing in Tmc1Δ/Δ;Tmc2Δ/Δ mice. TMC1-mCherry and TMC2-AcGFP localize along the length of immature stereocilia. However, as hair cells develop, the two proteins localize predominantly to stereocilia tips. Both TMCs are absent from the tips of the tallest stereocilia, where MET activity is not detectable. This distribution was confirmed for the endogenous proteins by immunofluorescence. These data are consistent with TMC1 and TMC2 being components of the stereocilia MET channel complex.

  3. Electronmicroscopic Investigations on the Role of Vesicle-like Bodies in Inner Ear Maculae for Fish Otolith Growth

    Science.gov (United States)

    Ibsch, M.; Vöhringer, P.; Anken, R. H.; Rahmann, H.

    The presence, morphology and possible origin of vesicle-like bodies (VBs) within the inner ear otolithic membrane of developmental stages of cichlid fish Oreochromis mossambicus and adult swordtail fish Xiphophorus helleri was analysed by means of transmission and scanning electron microscopy (TEM and SEM, respectively) employing various fixation procedures. The VBs are believed to be involved in the formation of the otolith (or statolith in birds and mammals) regarding the supply of the otolith's organic material. Increasing the osmolarity of the fixation medium decreased the number of VBs seen. Decalcification ended up in a complete disappearance of the VBs. Whilst a fixation with glutaraldehyde followed by OS04 fixation yielded numerous VBs, only few of them were observed when the tissue was fixed with glutaraldehyde and OSO4 simultaneously. Therefore, the results strongly suggest that the VBs are fixative (i.e., glutaraldehyde) induced artifacts, so-called blisters. With this, the supply of an oto- or statolith's organic material remains obscure. Possibly, it is provided by secretion from the supporting cells as has been hypothesized earlier

  4. Histopathology of the Inner Ear in a Case With Recent Onset of Cogan's Syndrome: Evidence for Vasculitis.

    Science.gov (United States)

    Jung, David H; Nadol, Joseph B; Folkerth, Rebecca D; Merola, Joseph F

    2016-01-01

    The association of sensorineural hearing loss and vertigo with inflammatory eye disease, usually interstitial keratitis, has been called Cogan's syndrome. The pathogenesis of Cogan's syndrome is unknown, but it has been assumed to be an immune mediated disorder with vasculitis. The histopathology of the inner ear in Cogan's syndrome has been described in 6 case reports. Although common pathologic findings in these reports include degeneration of the auditory and vestibular neuroepithelium, endolymphatic hydrops, fibrosis, and new bone formation, direct pathologic evidence of a vasculitis has not been published. A possible reason for this failure to identify vasculitis was a substantial delay (range, 4-40 years) between the onset of symptoms and examination of the otopathology. In the current case report, the patient had both auditory and vestibular symptoms and interstitial keratitis with a time delay of only 2 to 4 weeks between symptoms and death. Evidence of a vasculitis as a possible underlying etiology included H&E histopathology and anti-CD45 immunostaining of vessels both in the auditory and vestibular systems, supporting the hypothesis of a vasculitis as a mechanism in this disorder.

  5. Molecular bases of K+ secretory cells in the inner ear: shared and distinct features between birds and mammals

    Science.gov (United States)

    Wilms, Viviane; Köppl, Christine; Söffgen, Chris; Hartmann, Anna-Maria; Nothwang, Hans Gerd

    2016-01-01

    In the cochlea, mammals maintain a uniquely high endolymphatic potential (EP), which is not observed in other vertebrate groups. However, a high [K+] is always present in the inner ear endolymph. Here, we show that Kir4.1, which is required in the mammalian stria vascularis to generate the highly positive EP, is absent in the functionally equivalent avian tegmentum vasculosum. In contrast, the molecular repertoire required for K+ secretion, specifically NKCC1, KCNQ1, KCNE1, BSND and CLC-K, is shared between the tegmentum vasculosum, the vestibular dark cells and the marginal cells of the stria vascularis. We further show that in barn owls, the tegmentum vasculosum is enlarged and a higher EP (~+34 mV) maintained, compared to other birds. Our data suggest that both the tegmentum vasculosum and the stratified stria vascularis evolved from an ancestral vestibular epithelium that already featured the major cell types of the auditory epithelia. Genetic recruitment of Kir4.1 specifically to strial melanocytes was then a crucial step in mammalian evolution enabling an increase in the cochlear EP. An increased EP may be related to high-frequency hearing, as this is a hallmark of barn owls among birds and mammals among amniotes. PMID:27680950

  6. The effect of hair bundle shape on hair bundle hydrodynamics of inner ear hair cells at low and high frequencies.

    Science.gov (United States)

    Shatz, L F

    2000-03-01

    The relationship between size and shape of the hair bundle of a hair cell in the inner ear and its sensitivity at asymptotically high and low frequencies was determined, thereby extending the results of an analysis of hair bundle hydrodynamics in two dimensions (Freeman and Weiss, 1990. Hydrodynamic analysis of a two-dimensional model for micromechanical resonance of free-standing hair bundles. Hear. Res. 48, 37-68) to three dimensions. A hemispheroid was used to represent the hair bundle. The hemispheroid had a number of advantages: it could represent shapes that range from thin, pencil-like shapes, to wide, flat, disk-like shapes. Also analytic methods could be used in the high frequency range to obtain an exact solution to the equations of motion. In the low frequency range, where an approximate solution was found using boundary element methods, the sensitivity of the responses of hair cells was mainly proportional to the cube of the heights of their hair bundles, and at high frequencies, the sensitivity of the hair cells was mainly proportional to the inverse of their heights. An excellent match was obtained between measurements of sensitivity curves in the basillar papilla of the alligator and bobtail lizards and the model's predictions. These results also suggest why hair bundles of hair cells in vestibular organs which are sensitive to low frequencies have ranges of heights that are an order of magnitude larger than the range of heights of hair bundles of hair cells found in auditory organs.

  7. DYNAMIC ANALYSIS OF FLUID-STRUCTURE INTERACTION OF ENDOLYMPH AND CUPULA IN THE LATERAL SEMICIRCULAR CANAL OF INNER EAR

    Institute of Scientific and Technical Information of China (English)

    WU Cai-qin; HUA Cheng; YANG Lin; DAI Pei-dong; ZHANG Tian-yu; WANG Ke-qiang

    2011-01-01

    The semicircular canals,composed of lateral,anterior and posterior canals in the inner ear,are the sensors of equilibrium during head rotation movements in the three-dimensional space.Semicircular canals are filled with endolymph confined by the cupula.The study of the relationship between endolymph flow and cupular deformation is important in revealing the semicircular canals biomechanical behavior.To date,there are few studies focusing on the transient endolymph flow and cupular deformation in response to a head rotation motion.The lateral semicircular canal is mainly responsible for the sense of the horizontal rotation movement.In order to figure out the intricate dynamics in the lateral semicircular canal during the head rotation motion,the time evolutions of both endolymph flow and cupular deformation are analyzed in this article by using a fully coupled fluid-structure interaction model.It is shown that the cupular deformation provides cues for understanding the physiology of sensing the head rotation.

  8. Spiral ligament fibrocyte-derived MCP-1/CCL2 contributes to inner ear inflammation secondary to nontypeable H. influenzae-induced otitis media

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    Lim David J

    2010-10-01

    Full Text Available Abstract Background Otitis media (OM, one of the most common pediatric infectious diseases, causes inner ear inflammation resulting in vertigo and sensorineural hearing loss. Previously, we showed that spiral ligament fibrocytes (SLFs recognize OM pathogens and up-regulate chemokines. Here, we aim to determine a key molecule derived from SLFs, contributing to OM-induced inner ear inflammation. Methods Live NTHI was injected into the murine middle ear through the tympanic membrane, and histological analysis was performed after harvesting the temporal bones. Migration assays were conducted using the conditioned medium of NTHI-exposed SLFs with and without inhibition of MCP-1/CCL2 and CCR2. qRT-PCR analysis was performed to demonstrate a compensatory up-regulation of alternative genes induced by the targeting of MCP-1/CCL2 or CCR2. Results Transtympanic inoculation of live NTHI developed serous and purulent labyrinthitis after clearance of OM. THP-1 cells actively migrated and invaded the extracellular matrix in response to the conditioned medium of NTHI-exposed SLFs. This migratory activity was markedly inhibited by the viral CC chemokine inhibitor and the deficiency of MCP-1/CCL2, indicating that MCP-1/CCL2 is a main attractant of THP-1 cells among the SLF-derived molecules. We further demonstrated that CCR2 deficiency inhibits migration of monocyte-like cells in response to NTHI-induced SLF-derived molecules. Immunolabeling showed an increase in MCP-1/CCL2 expression in the cochlear lateral wall of the NTHI-inoculated group. Contrary to the in vitro data, deficiency of MCP-1/CCL2 or CCR2 did not inhibit OM-induced inner ear inflammation in vivo. We demonstrated that targeting MCP-1/CCL2 enhances NTHI-induced up-regulation of MCP-2/CCL8 in SLFs and up-regulates the basal expression of CCR2 in the splenocytes. We also found that targeting CCR2 enhances NTHI-induced up-regulation of MCP-1/CCL2 in SLFs. Conclusions Taken together, we suggest that

  9. Identification and characterization of an inner ear-expressed human melanoma inhibitory activity (MIA)-like gene (MIAL) with a frequent polymorphism that abolishes translation

    DEFF Research Database (Denmark)

    Rendtorff, Nanna Dahl; Frödin, M; Attié-Bitach, T

    2001-01-01

    in mammalian cell cultures showed that MIAL is translated as an approximately 15-kDa polypeptide that is assembled into a covalently linked homodimer, modified by sulfation, and secreted from the cells via the Golgi apparatus. In the human MIAL gene, a frequent polymorphism was discovered in the translation...... activity-like (MIAL; HGMW-approved symbol OTOR alias MIAL) gene. In situ hybridization revealed MIAL expression in a cell layer beneath the sensory epithelium of cochlea and vestibule of human fetal inner ear. No other human tissue, except fetal brain, showed expression of MIAL when analyzed by in situ...... hybridization or reverse transcription-polymerase chain reaction. The cDNA of the mouse homologue was also cloned and mapped about 80 cM from the top of mouse chromosome 2. In mouse, Mial was also expressed in the cochlea and the vestibule of the inner ear, as well as in brain, eye, limb, and ovary. Expression...

  10. Middle and inner ear malformations in mutation-proven branchio-oculo-facial (BOF) syndrome: case series and review of the literature.

    Science.gov (United States)

    Carter, Melissa T; Blaser, Susan; Papsin, Blake; Meschino, Wendy; Reardon, Willie; Klatt, Regan; Babul-Hirji, Riyana; Milunsky, Jeff; Chitayat, David

    2012-08-01

    Hearing impairment is common in individuals with branchio-oculo-facial (BOF) syndrome. The majority of described individuals have conductive hearing impairment due to malformed ossicles and/or external canal stenosis or atresia, although a sensorineural component to the hearing impairment in BOF syndrome is increasingly being reported. Sophisticated computed tomography (CT) of the temporal bone has revealed middle and inner ear malformations in three previous reports. We present middle and inner ear abnormalities in three additional individuals with mutation-proven BOF syndrome. We suggest that temporal bone CT imaging be included in the medical workup of a child with BOF syndrome, in order to guide management. Copyright © 2012 Wiley Periodicals, Inc.

  11. MALFORMACIÓN CONGÉNITA DE OÍDO INTERNO: CAVIDAD ÚNICA. Congenital malfomation of inner ear: single cavity

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    Julio César Torres Pazmiño

    2010-01-01

    Full Text Available Las malformaciones congénitas del oído interno son patologías de baja frecuencia pero que requieren precisión diagnóstica. Se presenta un caso de cavidad única o común con sus correspondientes imágenes radiológicas manejado con implante coclear, así como la revisión de la clasificación y diagnóstico diferencial de las demás anomalías de oído interno.Congenital malformations of the inner ear are rare conditions, but their detection requires high diagnostic accuracy. In this report we describe the case of a patient with single or common cavity, discuss the corresponding radiological images, describe the tratment of this patient with a cochlear implant, and review the classification and differential diagnosis of the other anomalies of the inner ear.

  12. Integration of transcriptomics, proteomics, and microRNA analyses reveals novel microRNA regulation of targets in the mammalian inner ear.

    Directory of Open Access Journals (Sweden)

    Tal Elkan-Miller

    Full Text Available We have employed a novel approach for the identification of functionally important microRNA (miRNA-target interactions, integrating miRNA, transcriptome and proteome profiles and advanced in silico analysis using the FAME algorithm. Since miRNAs play a crucial role in the inner ear, demonstrated by the discovery of mutations in a miRNA leading to human and mouse deafness, we applied this approach to microdissected auditory and vestibular sensory epithelia. We detected the expression of 157 miRNAs in the inner ear sensory epithelia, with 53 miRNAs differentially expressed between the cochlea and vestibule. Functionally important miRNAs were determined by searching for enriched or depleted targets in the transcript and protein datasets with an expression consistent with the dogma of miRNA regulation. Importantly, quite a few of the targets were detected only in the protein datasets, attributable to regulation by translational suppression. We identified and experimentally validated the regulation of PSIP1-P75, a transcriptional co-activator previously unknown in the inner ear, by miR-135b, in vestibular hair cells. Our findings suggest that miR-135b serves as a cellular effector, involved in regulating some of the differences between the cochlear and vestibular hair cells.

  13. Hearing Loss Controlled by Optogenetic Stimulation of Nonexcitable Nonglial Cells in the Cochlea of the Inner Ear

    Directory of Open Access Journals (Sweden)

    Mitsuo P. Sato

    2017-09-01

    Full Text Available Light-gated ion channels and transporters have been applied to a broad array of excitable cells including neurons, cardiac myocytes, skeletal muscle cells and pancreatic β-cells in an organism to clarify their physiological and pathological roles. Nonetheless, among nonexcitable cells, only glial cells have been studied in vivo by this approach. Here, by optogenetic stimulation of a different nonexcitable cell type in the cochlea of the inner ear, we induce and control hearing loss. To our knowledge, deafness animal models using optogenetics have not yet been established. Analysis of transgenic mice expressing channelrhodopsin-2 (ChR2 induced by an oligodendrocyte-specific promoter identified this channel in nonglial cells—melanocytes—of an epithelial-like tissue in the cochlea. The membrane potential of these cells underlies a highly positive potential in a K+-rich extracellular solution, endolymph; this electrical property is essential for hearing. Illumination of the cochlea to activate ChR2 and depolarize the melanocytes significantly impaired hearing within a few minutes, accompanied by a reduction in the endolymphatic potential. After cessation of the illumination, the hearing thresholds and potential returned to baseline during several minutes. These responses were replicable multiple times. ChR2 was also expressed in cochlear glial cells surrounding the neuronal components, but slight neural activation caused by the optical stimulation was unlikely to be involved in the hearing impairment. The acute-onset, reversible and repeatable phenotype, which is inaccessible to conventional gene-targeting and pharmacological approaches, seems to at least partially resemble the symptom in a population of patients with sensorineural hearing loss. Taken together, this mouse line may not only broaden applications of optogenetics but also contribute to the progress of translational research on deafness.

  14. Model for the immune-mediated inner ear disease and expression of interferon-γ in the inner ear%免疫性内耳病模型的建立及其内耳干扰素-γ的表达

    Institute of Scientific and Technical Information of China (English)

    马荧雪; 谭长强; 曹影; 王培蓓; 陈智斌

    2013-01-01

    目的:建立免疫性内耳病(IMIED)模型,并检测内耳干扰素-γ(IFN-γ)表达的变化情况.方法:将20只豚鼠按配对设计方法分为实验组和对照组.实验组采用钥孔戚血蓝蛋白(KLH)在已致敏的豚鼠圆窗龛局部免疫,对照组用PBS代替KLH免疫豚鼠;观察血清中特异性KLH抗体水平、听觉功能及内耳病理形态变化,并行酶免疫组化试验观察内耳IFN-γ的表达.结果:实验组免疫前后ABRⅢ波阈值的均值差异有统计学意义(P<0.05),免疫后实验组有7只动物(12耳)出现听损,且血清中特异性KLH抗体水平较免疫前明显升高(P<0.05);对照组免疫前后ABRⅢ波阈值的均值和血清KLH抗体水平的差异均无统计学意义(P>0.05);免疫后实验组ABRⅢ波阈值的均值和血清KLH抗体水平均高于对照组(P<0.05).实验组免疫后内耳组织中有炎症细胞浸润,部分豚鼠内耳有迷路积水.对照组豚鼠内耳组织中无明显IFN-γ表达,实验组IFN-γ表达主要分布在血管纹、螺旋韧带、螺旋神经节、Corti器及蜗轴小血管周围.结论:在已致敏的豚鼠圆窗龛局部免疫,诱导并造成IMIED模型的成功率较高.正常豚鼠内耳中几乎没有IFN-γ表达,而在IMIED豚鼠内耳中IFN-γ有显著表达,提示IMIED发生发展可能与IFN-γ表达有关.%Objective: To establish a model of immune-mediated inner ear disease( IMIED ) and to study the change of interferon- γ( IFN- γ ) expression in the inner ear. Methods: Twenty guinea pigs were divided into experimental group and control group with paired design. The round windows of systemically pre- sensitized guinea pigs were locally immunized with keyhole limpet hemocyanin( KLH ) in experimental group and PBS in the control group. Then the anti- KLH level and auditory function were determined before immunization and at 2 weeks after immunization. Tissue paraffin sections of temporal bone was made and observed by microscopy, and IFN- γ expression

  15. Ear Infection (Middle Ear)

    Science.gov (United States)

    Ear infection (middle ear) Overview By Mayo Clinic Staff An ear infection (acute otitis media) is most often a bacterial or viral infection that affects the middle ear, the air-filled space behind the eardrum that ...

  16. Tfap2a promotes specification and maturation of neurons in the inner ear through modulation of Bmp, Fgf and notch signaling.

    Science.gov (United States)

    Kantarci, Husniye; Edlund, Renee K; Groves, Andrew K; Riley, Bruce B

    2015-03-01

    Neurons of the statoacoustic ganglion (SAG) transmit auditory and vestibular information from the inner ear to the hindbrain. SAG neuroblasts originate in the floor of the otic vesicle. New neuroblasts soon delaminate and migrate towards the hindbrain while continuing to proliferate, a phase known as transit amplification. SAG cells eventually come to rest between the ear and hindbrain before terminally differentiating. Regulation of these events is only partially understood. Fgf initiates neuroblast specification within the ear. Subsequently, Fgf secreted by mature SAG neurons exceeds a maximum threshold, serving to terminate specification and delay maturation of transit-amplifying cells. Notch signaling also limits SAG development, but how it is coordinated with Fgf is unknown. Here we show that transcription factor Tfap2a coordinates multiple signaling pathways to promote neurogenesis in the zebrafish inner ear. In both zebrafish and chick, Tfap2a is expressed in a ventrolateral domain of the otic vesicle that includes neurogenic precursors. Functional studies were conducted in zebrafish. Loss of Tfap2a elevated Fgf and Notch signaling, thereby inhibiting SAG specification and slowing maturation of transit-amplifying cells. Conversely, overexpression of Tfap2a inhibited Fgf and Notch signaling, leading to excess and accelerated SAG production. However, most SAG neurons produced by Tfap2a overexpression died soon after maturation. Directly blocking either Fgf or Notch caused less dramatic acceleration of SAG development without neuronal death, whereas blocking both pathways mimicked all observed effects of Tfap2a overexpression, including apoptosis of mature neurons. Analysis of genetic mosaics showed that Tfap2a acts non-autonomously to inhibit Fgf. This led to the discovery that Tfap2a activates expression of Bmp7a, which in turn inhibits both Fgf and Notch signaling. Blocking Bmp signaling reversed the effects of overexpressing Tfap2a. Together, these data

  17. Evolution of vertebrate mechanosensory hair cells and inner ears: toward identifying stimuli that select mutation driven altered morphologies.

    Science.gov (United States)

    Fritzsch, Bernd; Straka, Hans

    2014-01-01

    Among the major distance senses of vertebrates, the ear is unique in its complex morphological changes during evolution. Conceivably, these changes enable the ear to adapt toward sensing various physically well-characterized stimuli. This review develops a scenario that integrates sensory cell with organ evolution. We propose that molecular and cellular evolution of the vertebrate hair cells occurred prior to the formation of the vertebrate ear. We previously proposed that the genes driving hair cell differentiation were aggregated in the otic region through developmental re-patterning that generated a unique vertebrate embryonic structure, the otic placode. In agreement with the presence of graviceptive receptors in many vertebrate outgroups, it is likely that the vertebrate ear originally functioned as a simple gravity-sensing organ. Based on the rare occurrence of angular acceleration receptors in vertebrate outgroups, we further propose that the canal system evolved with a more sophisticated ear morphogenesis. This evolving morphogenesis obviously turned the initial otocyst into a complex set of canals and recesses, harboring multiple sensory epithelia each adapted to the acquisition of a specific aspect of a given physical stimulus. As support for this evolutionary progression, we provide several details of the molecular basis of ear development.

  18. Technical Details of Sample Preparation for Inner Ear Organotypic Cultures%幼鼠内耳单个器官培养步骤及分类方法

    Institute of Scientific and Technical Information of China (English)

    于进涛; 丁大连; 李鹏; 高可雷; 蒋海燕; 孙虹; Richard J. Salvi

    2015-01-01

    In vitro culture techniques have important values in the investigation of inner ear cellular functions, organic development, cell degeneration and/or cell regeneration. Since structures of the inner ear are tiny and complex, sample prepara⁃tion for organotypic culture of the inner ear can be difficult, despite that relevant techniques have been introduced briefly in numerous earlier publications. Based upon decades of culturing practices with inner ear end-organs in this lab, this article ad⁃dresses the technical aspects of inner ear organic culturing by firstly presenting a brief review of various culture methods for different inner ear materials. Detailed step by step protocols for sample preparation, collection and culture are also described. This presentation provides detailed operative guidelines regarding useful techniques and tricks in micro-dissection of the whole membranous labyrinth, in sample preparation, collagen gel preparation and sample layer mountings with detailed illus⁃trations. We hope this article can serve as an additional reading material supplementing previous literatures that lack detailed technical information for beginners in this field.%内耳离体培养在研究内耳细胞功能、内耳组织发育再生、细胞损伤退化等方面具有重要价值。但由于内耳的组织结构微小复杂,其取材和培养具有较大难度,使该技术的普及和应用受到一定限制。本文在简要点评不同内耳离体培养方法优劣的基础上,结合本实验室多年来积累的实践经验,详细介绍了新生大鼠各个内耳终器取材及培养的具体步骤。从解剖迷路到分离终器,从凝胶制备到标本铺放,都有详细的操作指南,本文还针对各环节中的技术动作和关键事项进行了具体探讨并配以指导图例,希望这些内容能够弥补以往文献中抽象简略的条款式步骤所造成的实验困难,为开展内耳器官培养研究的初学者提供一定的帮助。

  19. Nanoparticle Mediated Drug Delivery of Rolipram to Tyrosine Kinase B Positive Cells in the Inner Ear with Targeting Peptides and Agonistic Antibodies

    Directory of Open Access Journals (Sweden)

    Rudolf eGlueckert

    2015-05-01

    Full Text Available AimSystemic pharmacotherapies have limitation due to blood-labyrinth barrier, so local delivery via the round window membrane opens a path for effective treatment. Multifunctional nanoparticle (NP mediated cell specific drug delivery may enhance efficacy and reduce side effects. Different NPs with ligands to target TrkB receptor were tested. Distribution, uptake mechanisms, trafficking, and bioefficacy of drug release of rolipram loaded NPs were evaluated.Methods We tested lipid based nanocapsules (LNCs, Quantum Dot, silica NPs with surface modification by peptides mimicking TrkB or TrkB activating antibodies. Bioefficacy of drug release was tested with rolipram loaded LNCs to prevent cisplatin induced apoptosis. We established different cell culture models with SH-SY-5Y and inner ear derived cell lines and used neonatal and adult mouse explants. Uptake and trafficking was evaluated with FACS and confocal as well as transmission electron microscopy. ResultsPlain NPs show some selectivity in uptake related to the in-vitro system properties, carrier material and NP size. Some peptide ligands provide enhanced targeted uptake to neuronal cells but failed to show this in cell cultures. Agonistic antibodies linked to silica NPs showed TrkB activation and enhanced binding to inner ear derived cells. Rolipram loaded LNCs proved as effective carriers to prevent cisplatin induced apoptosis.DiscussionMost NPs with targeting ligands showed limited effects to enhance uptake. NP aggregation and unspecific binding may change uptake mechanisms and impair endocytosis by an overload of NPs. This may affect survival signaling. NPs with antibodies activate survival signaling and show effective binding to TrkB positive cells but needs further optimization for specific internalization. Bioefficiacy of rolipram release confirms LNCs as encouraging vectors for drug delivery of lipophilic agents to the inner ear with ideal release characteristics independent of

  20. Ankrd6 is a mammalian functional homolog of Drosophila planar cell polarity gene diego and regulates coordinated cellular orientation in the mouse inner ear.

    Science.gov (United States)

    Jones, Chonnettia; Qian, Dong; Kim, Sun Myoung; Li, Shuangding; Ren, Dongdong; Knapp, Lindsey; Sprinzak, David; Avraham, Karen B; Matsuzaki, Fumio; Chi, Fanglu; Chen, Ping

    2014-11-01

    The coordinated polarization of neighboring cells within the plane of the tissue, known as planar cell polarity (PCP), is a recurring theme in biology. It is required for numerous developmental processes for the form and function of many tissues and organs across species. The genetic pathway regulating PCP was first discovered in Drosophila, and an analogous but distinct pathway is emerging in vertebrates. It consists of membrane protein complexes known as core PCP proteins that are conserved across species. Here we report that the over-expression of the murine Ankrd6 (mAnkrd6) gene that shares homology with Drosophila core PCP gene diego causes a typical PCP phenotype in Drosophila, and mAnkrd6 can rescue the loss of function of diego in Drosophila. In mice, mAnkrd6 protein is asymmetrically localized in cells of the inner ear sensory organs, characteristic of components of conserved core PCP complexes. The loss of mAnkrd6 causes PCP defects in the inner ear sensory organs. Moreover, canonical Wnt signaling is significantly increased in mouse embryonic fibroblasts from mAnkrd6 knockout mice in comparison to wild type controls. Together, these results indicated that mAnkrd6 is a functional homolog of the Drosophila diego gene for mammalian PCP regulation and act to suppress canonical Wnt signaling.

  1. Individual Behavioral Adaptability to Diminished G-Forces and Calcium Uptake of Inner ear Otoliths in Fish. A Sounding Rocket Experiment (TX 48)

    Science.gov (United States)

    Knie, Miriam; Shcherbakov, Denis; Hilbig, Reinhard

    2013-02-01

    In the course of the TEXUS 45 experiment we were able to show that the time-course of a habituation to diminished gravity depends on the respective G-level HQM (high quality microgravity, 10-4g) vs. LQM (low quality microgravity, 10-2g) and on the symmetric morphology of the gravity sensing components of the inner ear. An individually different regulation of inner ear otolith calcification plays a role in this process. With this study, the results of the TEXUS 45 flight were validated for another g-level (9x10-4g). In the course of the behavioural investigations we were able to show that most fish could adapt to these μg condition. Fish experiencing permanently 9x10-4g during the whole flight exhibit less kinetotic movements and from this we conclude, that they might use this minimal g-force for orientation. Furthermore these behavioural data were correlated with the morphology of otoliths (Lapilli and Sagittae).

  2. In vitro differentiation of mouse embryonic stem cells into inner ear hair cell-like cells using stromal cell conditioned medium.

    Science.gov (United States)

    Ouji, Y; Ishizaka, S; Nakamura-Uchiyama, F; Yoshikawa, M

    2012-05-24

    Hearing loss is mainly caused by loss of sensory hair cells (HCs) in the organ of Corti or cochlea. Although embryonic stem (ES) cells are a promising source for cell therapy, little is known about the efficient generation of HC-like cells from ES cells. In the present study, we developed a single-medium culture method for growing embryoid bodies (EBs), in which conditioned medium (CM) from cultures of ST2 stromal cells (ST2-CM) was used for 14-day cultures of 4-day EBs. At the end of the 14-day cultures, up to 20% of the cells in EB outgrowths expressed HC-related markers, including Math1 (also known as Atoh1), myosin6, myosin7a, calretinin, α9AchR and Brn3c (also known as Pou4f3), and also showed formation of stereocilia-like structures. Further, we found that these cells were incorporated into the developing inner ear after transplantation into chick embryos. The present inner ear HC induction method using ST2-CM (HIST2 method) is quite simple and highly efficient to obtain ES-derived HC-like cells with a relatively short cultivation time.

  3. Anatomical evidence for low frequency sensitivity in an archaeocete whale: comparison of the inner ear of Zygorhiza kochii with that of crown Mysticeti.

    Science.gov (United States)

    Ekdale, Eric G; Racicot, Rachel A

    2015-01-01

    The evolution of hearing in cetaceans is a matter of current interest given that odontocetes (toothed whales) are sensitive to high frequency sounds and mysticetes (baleen whales) are sensitive to low and potentially infrasonic noises. Earlier diverging stem cetaceans (archaeocetes) were hypothesized to have had either low or high frequency sensitivity. Through CT scanning, the morphology of the bony labyrinth of the basilosaurid archaeocete Zygorhiza kochii is described and compared to novel information from the inner ears of mysticetes, which are less known than the inner ears of odontocetes. Further comparisons are made with published information for other cetaceans. The anatomy of the cochlea of Zygorhiza is in line with mysticetes and supports the hypothesis that Zygorhiza was sensitive to low frequency noises. Morphological features that support the low frequency hypothesis and are shared by Zygorhiza and mysticetes include a long cochlear canal with a high number of turns, steeply graded curvature of the cochlear spiral in which the apical turn is coiled tighter than the basal turn, thin walls separating successive turns that overlap in vestibular view, and reduction of the secondary bony lamina. Additional morphology of the vestibular system indicates that Zygorhiza was more sensitive to head rotations than extant mysticetes are, which likely indicates higher agility in the ancestral taxon.

  4. Histology and synchrotron radiation-based microtomography of the inner ear in a molecularly confirmed case of CHARGE syndrome.

    NARCIS (Netherlands)

    Glueckert, R.; Rask-Andersen, H.; Sergi, C.; Schmutzhard, J.; Mueller, B.; Beckmann, F.; Rittinger, O.; Hoefsloot, L.H.; Schrott-Fischer, A.; Janecke, A.R.

    2010-01-01

    CHARGE (Coloboma of the iris or retina, heart defects, atresia of the choanae, retardation of growth and/or development, genital anomalies, ear anomalies) syndrome (OMIM #214800) affects about 1 in 10,000 children and is most often caused by chromodomain helicase DNA-binding protein-7 (CHD7) mutatio

  5. Ototoxicity (Ear Poisoning) (For Parents)

    Science.gov (United States)

    ... Teaching Kids to Be Smart About Social Media Ototoxicity (Ear Poisoning) KidsHealth > For Parents > Ototoxicity (Ear Poisoning) Print A A A What's in ... result of taking the drugs. This is called ototoxicity or " ear poisoning ." Ototoxicity damages the inner ear — ...

  6. Sports injuries of the ear.

    Science.gov (United States)

    Wagner, G A

    1972-07-01

    The author describes common sports injuries involving the ear. Such injuries include hematoma, lacerations, foreign bodies (tattoo), and thermal injuries. Ear canal injuries include swimmer's ear and penetrating injuries. Tympanum injuries include tympanic membrane perforations, ossicular discontinuity, eustachian tube dysfunction, temporal bone fractures and traumatic facial nerve palsy. Inner ear injuries include traumatic sensorineural deafness. The author emphasizes the management of these injuries.

  7. Effects of altered gravity on the expression of Calcium -binding and matrix proteins in the inner ear of developing fish following ∆g-expositions.

    Science.gov (United States)

    Hilbig, Reinhard; Hendrik Anken, Ralf; Weigele, Jochen

    The results of the Foton-M3 mission (OmegaHab) give evidence that the otoliths of the fish form OmegaHab were larger as compared to the ground control. Additionally the shape (raphe) and morphology especially the mode of crystallization of the otoliths were affected during growth in weightlessness. The reason for these changes is assumed to originate from changes in the composition of the otolith matrix and Ca-binding proteins (OMP). The OMPs play an important role in controlling the crystallization process and additionally the morphology of crystals, determining the crystallpolymorph and the strength of the crystals. The matrix of otoliths is a complex functional structure containing several calcium-binding proteins, structural proteins and protease inhibitors. Furthermore it is composed of otolith matrix protein-1, Otolin, Otoconin, SPARC and Neuroserpin, which is a specific expression in the otolth matrix for chichlid fish. During embryonic development of the fish inner ear, these proteins show a spacial and temporal expression pattern. The formation of the inner ear -including otoliths and sensory cells -starting from the otocyst-anlage -can be subdivided in several major developmental stages e.g. the forming of the otic cavity (stage 7/8), the tetha cell or seeding stage (stage 8, 9), the development of the semicircular channels (stage 12), the transition to further daily growth (post stage15) and the development of the third otolith, asteriscus (stage 23). These developmental phases contain different constitutions or involvements of matrix proteins. We investigated the matrixprotein composition of the chichlid fish Oreochromis mossambicus and found that the otolith matrix differentiate between other fishes. In this case some matrix proteins seem to be uniform in fishes, other known matrix proteins are lacking and we have also references to new candidates for matrix proteins chichlids. In this case we investigated the expression of the matrix proteins otolith

  8. Planar cell polarity and a potential role for a Wnt morphogen gradient in stereociliary bundle orientation in the mammalian inner ear.

    Science.gov (United States)

    Dabdoub, Alain; Kelley, Matthew W

    2005-09-15

    The planar cell polarity (PCP) pathway, a noncanonical Wnt signaling pathway, is crucial for embryonic development in all animals as it is responsible for the regulation of coordinated orientation of structures within the plane of the various epithelia. In the mammalian cochlea, one of the best examples of planar polarity in vertebrates, stereociliary bundles located on mechanosensory hair cells within the sensory epithelium are all uniformly polarized. Generation of this polarity is important for hair cell mechanotransduction and auditory perception as stereociliary bundles are only sensitive to vibrations in their single plane of polarization. We describe the two step developmental process that results in the generation of planar polarity in the mammalian inner ear. Furthermore, we review evidence for the role of Wnt signaling, and the possible generation of a Wnt gradient, in planar polarity.

  9. MALFORMACIÓN CONGÉNITA DE OÍDO INTERNO: CAVIDAD ÚNICA. Congenital malfomation of inner ear: single cavity

    OpenAIRE

    Julio César Torres Pazmiño; Gilberto Eduardo Marrugo Pardo

    2010-01-01

    Las malformaciones congénitas del oído interno son patologías de baja frecuencia pero que requieren precisión diagnóstica. Se presenta un caso de cavidad única o común con sus correspondientes imágenes radiológicas manejado con implante coclear, así como la revisión de la clasificación y diagnóstico diferencial de las demás anomalías de oído interno.Congenital malformations of the inner ear are rare conditions, but their detection requires high diagnostic accuracy. In this report we describe ...

  10. Transplantation and survival of mouse inner ear progenitor/stem cells in the organ of Corti after cochleostomy of hearing-impaired guinea pigs: preliminary results

    Directory of Open Access Journals (Sweden)

    L.C.M. Barboza Jr.

    2016-01-01

    Full Text Available In mammals, damage to sensory receptor cells (hair cells of the inner ear results in permanent sensorineural hearing loss. Here, we investigated whether postnatal mouse inner ear progenitor/stem cells (mIESCs are viable after transplantation into the basal turns of neomycin-injured guinea pig cochleas. We also examined the effects of mIESC transplantation on auditory functions. Eight adult female Cavia porcellus guinea pigs (250-350g were deafened by intratympanic neomycin delivery. After 7 days, the animals were randomly divided in two groups. The study group (n=4 received transplantation of LacZ-positive mIESCs in culture medium into the scala tympani. The control group (n=4 received culture medium only. At 2 weeks after transplantation, functional analyses were performed by auditory brainstem response measurement, and the animals were sacrificed. The presence of mIESCs was evaluated by immunohistochemistry of sections of the cochlea from the study group. Non-parametric tests were used for statistical analysis of the data. Intratympanic neomycin delivery damaged hair cells and increased auditory thresholds prior to cell transplantation. There were no significant differences between auditory brainstem thresholds before and after transplantation in individual guinea pigs. Some mIESCs were observed in all scalae of the basal turns of the injured cochleas, and a proportion of these cells expressed the hair cell marker myosin VIIa. Some transplanted mIESCs engrafted in the cochlear basilar membrane. Our study demonstrates that transplanted cells survived and engrafted in the organ of Corti after cochleostomy.

  11. Dopaminergic Innervation of the Mouse Inner Ear: Evidence for a Separate Cytochemical Group of Cochlear Efferent Fibers

    OpenAIRE

    2006-01-01

    Immunostaining mouse cochleas for tyrosine hydroxylase (TH) and dopamine β-hydroxylase suggests that there is a rich adrenergic innervation throughout the auditory nerve trunk and a small dopaminergic innervation of the sensory cell areas. Surgical cuts in the brainstem confirm these dopaminergic fibers as part of the olivocochlear efferent bundle. Within the sensory epithelium, TH-positive terminals are seen only in the inner hair cell area, where they intermingle with other olivocochlear te...

  12. Classification and diagnosis of ear malformations

    OpenAIRE

    Bartel-Friedrich, Sylva; Wulke, Cornelia

    2008-01-01

    In the ENT region 50% of the malformations affect the ear. Malformations of the outer and middle ear are predominantly unilateral (ca. 70-90%) and mostly involve the right ear. Inner ear malformations can be unilateral or bilateral. The incidence of ear malformations is approximately 1 in 3800 newborns. Ear malformations may be genetic (associated with syndromes or not, with family history, spontaneous mutations) or acquired in nature. Malformations can affect the outer ear (pinna and externa...

  13. 内耳结构异常患者的人工耳蜗植入术%Cochlear Implantation in Patients with Abnormal Inner Ear Structure

    Institute of Scientific and Technical Information of China (English)

    张宏征; 钱宇虹; 陈浩; 郭梦和

    2011-01-01

    目的 探讨对内耳结构异常患者行人工耳蜗植入的方法并评估其术后效果.方法 回顾性分析2000年1月~2010年5月行人工耳蜗植入术的24例内耳结构异常患者的临床资料,包括耳蜗骨化2例、Waardenburg综合征Ⅱ型8例、Mondini畸形12例、共同腔畸形1例、半规管缺如1例;随机选择30例内耳结构正常的相同年龄段接受了人工耳蜗植入的极重度感音性聋患者作为对照组;分析并比较两组患者的术前听力和影像学资料以及手术植入方法和术后听觉言语康复情况.结果 1例共同腔畸形和2例Mondini畸形患者术中出现井喷,另有10例Mondini畸形、2例Waardenburg综合征Ⅱ型病例在耳蜗钻孔后见外淋巴液搏动性涌出,经抬高头位降低液压并以筋膜粒严密封堵开窗口等处理完成电极植入;2例耳蜗骨化者经扩大开窗范围并剔除骨化组织后分别植入8个和12个电极;其余病例均经常规方法完成电极植入.内耳结构异常组患者人工耳蜗植入术后均获得听觉,所有患者均未出现严重并发症.术后6个月内耳结构异常组啭音声场测听平均听阈35.4±4.9 dB HL,闭合式词表言语识别率平均为75.18%±3.1%,开放式词表言语识别率平均为70.32%±2.5%;对照组上述三项结果分别为31.4±5.5 dB HL、81.63%±3.7%、76.77%±5.4%,两组间比较差异无统计学意义(P>0.05).结论 对内耳结构异常的极重度感音性聋患者行人工耳蜗植入安全有效,但针对不同的内耳畸形需采取不同的处理方法.%Objective To report the multi-channel cochlear implantation in patients with abnormal inner ear structure, and to evaluate the outcomes of speech rehabilitation. Methods Multi-channel cochlear implantation was conducted among 665 patients from 2000 to 2010. Twenty-four with abnormal inner ear structure were retrospective studied. There were 2 cases with cochlear ossification, 8 with Waarndenburg Syndrome, 12 with Mondini

  14. Travel Inside the Ear

    Medline Plus

    Full Text Available ... stirrup. These are the smallest bones in your body. Together they are smaller than an orange seed. It then travels into the inner ear, which ... organizations Related Topics ...

  15. Characteristics and application of inner ear CT for sensorineural hearing loss in children%儿童感音神经性耳聋20例内耳多层螺旋CT特征及应用分析

    Institute of Scientific and Technical Information of China (English)

    霍亮; 史贻芳; 王华

    2012-01-01

    目的 探讨儿童感音神经性耳聋(SNHL)内耳多层螺旋CT(MSCT)特点及其对诊断的价值.方法 选取2008年1月至2010年12月中国医科大学附属盛京医院经脑干听觉诱发电位(BAER)诊断儿童SNHL患儿65例,均行内耳MSCT扫描,然后行冠状面多平面重建(MPR).结果 20例(33只耳,45例次)存在内耳畸形,其中12只耳多种畸形并存,包括耳蜗畸形伴内耳道畸形5只耳;耳蜗畸形伴前庭导水管扩大3只耳;前庭畸形伴内耳道畸形2只耳;半规管畸形伴前庭导水管扩大1只耳;内耳道畸形伴前庭导水管扩大1只耳.45例次畸形中耳蜗畸形10例次[包括Michel型1例次、共同腔畸形2例次、耳蜗未发育1例次、耳蜗发育不全1例次、不完全分隔Ⅰ型2例次、不完全分隔Ⅱ型(Mondini畸形)3例次]、前庭畸形7例次、半规管畸形5例次、内耳道畸形8例次、前庭导水管扩大15例次.结论 根据MSCT检查结果显示多数SNHL患儿存在内耳畸形.内耳横断面MSCT扫描和冠状面MPR可对儿童先天性SNHL内耳畸形进行全面评估,从而为进一步指导治疗及预后提供有力依据.%Objective To evaluate the characteristics of inner ear multi-slice computed tomography (MSCT) in pediat-ric sensorineural hearing loss (SNHL) and feasibility and usability of diagnosis of SNHL. Methods Sixty-five patients have been diagnosed with sensorineural hearing loss (SNHL) by Brainstem Auditory Evoked Response (BAER). Inner ear MSCT scan and coronal multiplanar reformation (MPR) reconstruction were done in all cases. Results This study showed that 20 cases (33 ears,45 case times) were with inner ear malformations and 12 ears with two different malformations, including 5 ears with cochlear and internal auditory canal (IAC) malformations, 3 ears with cochlear and vestibu-lar malformations, 2 ears with vestibular and IAC malformations, 1 ear with semicircular canal and vestibular malformations, 1 ear with internal auditory

  16. Brn3c null mutant mice show long-term, incomplete retention of some afferent inner ear innervation

    Directory of Open Access Journals (Sweden)

    Pirvola Ulla

    2003-01-01

    Full Text Available Abstract Background Ears of Brn3c null mutants develop immature hair cells, identifiable only by certain molecular markers, and undergo apoptosis in neonates. This partial development of hair cells could lead to enough neurotrophin expression to sustain sensory neurons through embryonic development. We have therefore investigated in these mutants the patterns of innervation and of expression of known neurotrophins. Results At birth there is a limited expression of BDNF and NT-3 in the mutant sensory epithelia and DiI tracing shows no specific reduction of afferents or efferents that resembles neurotrophin null mutations. At postnatal day 7/8 (P7/8, innervation is severely reduced both qualitatively and quantitatively. 1% of myosin VIIa-positive immature hair cells are present in the mutant cochlea, concentrated in the base. Around 20% of immature hair cells exist in the mutant vestibular sensory epithelia. Despite more severe loss of hair cells (1% compared to 20%, the cochlea retains many more sensory neurons (46% compared to 15% than vestibular epithelia. Even 6 months old mutant mice have some fibers to all vestibular sensory epithelia and many more to the cochlear apex which lacks MyoVIIa positive hair cells. Topologically organized central cochlea projections exist at least until P8, suggesting that functional hair cells are not required to establish such projections. Conclusion The limited expression of neurotrophins in the cochlea of Brn3c null mice suffices to support many sensory neurons, particularly in the cochlea, until birth. The molecular nature of the long term survival of apical spiral neurons remains unclear.

  17. Clinical Features of Children with Congenital Malformations of Inner Ear in Sensorineural Hearing Loss%儿童感音神经性耳聋中先天性内耳畸形的临床特征

    Institute of Scientific and Technical Information of China (English)

    李幼瑾; 杨军; 李蕴

    2011-01-01

    目的:分析在儿童感音神经性耳聋(sensorineural hearing loss,SNHL)中先天性内耳畸形患儿的影像学及临床特征.方法:回顾分析860例SNHL患儿中因听力障碍(109例) 、外耳畸形(3例)、面部异常(13例)来就诊的125例(225耳)患儿的临床资料.结果:109例(87.2%)患儿因听力障碍就诊,母亲妊娠早期有感冒史52例(41.6%).166耳(73.8%)极重度耳聋,累及双侧100例(80%).颞骨高分辨率CT或磁共振成像(MRI)显示其中同时合并外耳及中耳畸形3耳,合并中耳畸形13耳.Michel 畸形2例(4耳),耳蜗不发育1例(1耳),共同腔畸形10例(14耳),不完全分隔-I型2例(2耳),耳蜗前庭发育不良2例(2耳),不完全分隔-II型(Mondini 畸形)19例(29耳).累及前庭导水管扩大91例(170耳)(75.6%),半规管畸形30例(46耳)(20.6%),内听道畸形35例(49耳)(21.7%).结论:前庭导水管扩大是儿童SNHL中最常见的内耳影像学异常.患儿多为双侧重度听力损失或全聋.对于先天性内耳畸形的患儿行高分辨率CT检查非常重要.%Objective: To study the clinical features of inner ear malformations with sensorineural hearing loss(SNHL)in children Methods: Retrospective chart review, 860 patients with SNHL,of which 125 children(225 ears) with inner ear malformations diagnosed with temporal bone computed tomography (CT) scans who referred to the Ear, Nose and Throat (ENT) Department of Children Medical Center from February 2005 to January 2010,109 cases due to hearing loss and other 3 cases due to external ear malformations, 13 cases due to face abnormality, were retrospectively studied. Results: A total of 109(87.2%) cases were found hearing loss, 52 cases (41.6%)mothers were noted to have caught a cold in first trimester of pregnancy. Hearing loss was typically bilateral in 100 ears(80% ) ,and profound sensorineural hearing loss in 166 ears (73.8%). Of the total, 3 ears were accompanied by outer and middle ear malformations, 13 ears accompanied by

  18. Disruption of SorCS2 reveals differences in the regulation of stereociliary bundle formation between hair cell types in the inner ear.

    Directory of Open Access Journals (Sweden)

    Andrew Forge

    2017-03-01

    Full Text Available Behavioural anomalies suggesting an inner ear disorder were observed in a colony of transgenic mice. Affected animals were profoundly deaf. Severe hair bundle defects were identified in all outer and inner hair cells (OHC, IHC in the cochlea and in hair cells of vestibular macular organs, but hair cells in cristae were essentially unaffected. Evidence suggested the disorder was likely due to gene disruption by a randomly inserted transgene construct. Whole-genome sequencing identified interruption of the SorCS2 (Sortilin-related VPS-10 domain containing protein locus. Real-time-qPCR demonstrated disrupted expression of SorCS2 RNA in cochlear tissue from affected mice and this was confirmed by SorCS2 immuno-labelling. In all affected hair cells, stereocilia were shorter than normal, but abnormalities of bundle morphology and organisation differed between hair cell types. Bundles on OHC were grossly misshapen with significantly fewer stereocilia than normal. However, stereocilia were organised in rows of increasing height. Bundles on IHC contained significantly more stereocilia than normal with some longer stereocilia towards the centre, or with minimal height differentials. In early postnatal mice, kinocilia (primary cilia of IHC and of OHC were initially located towards the lateral edge of the hair cell surface but often became surrounded by stereocilia as bundle shape and apical surface contour changed. In macular organs the kinocilium was positioned in the centre of the cell surface throughout maturation. There was disruption of the signalling pathway controlling intrinsic hair cell apical asymmetry. LGN and Gαi3 were largely absent, and atypical Protein Kinase C (aPKC lost its asymmetric distribution. The results suggest that SorCS2 plays a role upstream of the intrinsic polarity pathway and that there are differences between hair cell types in the deployment of the machinery that generates a precisely organised hair bundle.

  19. Disruption of SorCS2 reveals differences in the regulation of stereociliary bundle formation between hair cell types in the inner ear

    Science.gov (United States)

    Taylor, Ruth R.; Lovett, Michael; Jagger, Daniel J.

    2017-01-01

    Behavioural anomalies suggesting an inner ear disorder were observed in a colony of transgenic mice. Affected animals were profoundly deaf. Severe hair bundle defects were identified in all outer and inner hair cells (OHC, IHC) in the cochlea and in hair cells of vestibular macular organs, but hair cells in cristae were essentially unaffected. Evidence suggested the disorder was likely due to gene disruption by a randomly inserted transgene construct. Whole-genome sequencing identified interruption of the SorCS2 (Sortilin-related VPS-10 domain containing protein) locus. Real-time-qPCR demonstrated disrupted expression of SorCS2 RNA in cochlear tissue from affected mice and this was confirmed by SorCS2 immuno-labelling. In all affected hair cells, stereocilia were shorter than normal, but abnormalities of bundle morphology and organisation differed between hair cell types. Bundles on OHC were grossly misshapen with significantly fewer stereocilia than normal. However, stereocilia were organised in rows of increasing height. Bundles on IHC contained significantly more stereocilia than normal with some longer stereocilia towards the centre, or with minimal height differentials. In early postnatal mice, kinocilia (primary cilia) of IHC and of OHC were initially located towards the lateral edge of the hair cell surface but often became surrounded by stereocilia as bundle shape and apical surface contour changed. In macular organs the kinocilium was positioned in the centre of the cell surface throughout maturation. There was disruption of the signalling pathway controlling intrinsic hair cell apical asymmetry. LGN and Gαi3 were largely absent, and atypical Protein Kinase C (aPKC) lost its asymmetric distribution. The results suggest that SorCS2 plays a role upstream of the intrinsic polarity pathway and that there are differences between hair cell types in the deployment of the machinery that generates a precisely organised hair bundle. PMID:28346477

  20. Fdp, a new fibrocyte-derived protein related to MIA/CD-RAP, has an in vitro effect on the early differentiation of the inner ear mesenchyme.

    Science.gov (United States)

    Cohen-Salmon, M; Frenz, D; Liu, W; Verpy, E; Voegeling, S; Petit, C

    2000-12-22

    During the course of a study aimed at isolating transcripts specifically or preferentially expressed in the inner ear, we identified a novel gene, encoding a fibrocyte-derived protein, that we named Fdp. Fdp is predicted to be a secreted 128-amino acid protein, which is highly homologous to the melanoma-inhibiting activity/cartilage-derived retinoic acid-sensitive protein (MIA/CD-RAP), a cartilage-specific protein also expressed in several tumors. Fdp and MIA/CD-RAP thus define a new family of proteins. Fdp is expressed from embryonic day 10.5 in the mesenchyme surrounding the otic epithelium. During development, these cells progressively aggregate, condense, and differentiate into cartilaginous cells forming the otic capsule, which no longer expresses Fdp, and into fibrocytes surrounding the epithelia, which strongly express Fdp. In order to address the function of Fdp, we developed an in vitro antisense oligonucleotide approach using microdissected periotic mesenchyme micromass cultures, and showed that Fdp antisense oligonucleotide treatment results in a significant reduction in chondrogenesis. Our results demonstrate that Fdp plays a role in the initiation of periotic mesenchyme chondrogenesis. Accordingly, Fdp and its human ortholog FDP, which map to chromosome 2 and band 20p11, respectively, could be candidate genes for forms of deafness associated with malformations of the otic capsule.

  1. A genome-wide linkage and association study of musical aptitude identifies loci containing genes related to inner ear development and neurocognitive functions

    Science.gov (United States)

    Oikkonen, J.; Huang, Y.; Onkamo, P.; Ukkola-Vuoti, L.; Raijas, P.; Karma, K.; Vieland, V. J.; Järvelä, I.

    2014-01-01

    Humans have developed the perception, production and processing of sounds into the art of music. A genetic contribution to these skills of musical aptitude has long been suggested. We performed a genome-wide scan in 76 pedigrees (767 individuals) characterized for the ability to discriminate pitch (SP), duration (ST) and sound patterns (KMT), which are primary capacities for music perception. Using the Bayesian linkage and association approach implemented in program package KELVIN, especially designed for complex pedigrees, several SNPs near genes affecting the functions of the auditory pathway and neurocognitive processes were identified. The strongest association was found at 3q21.3 (rs9854612) with combined SP, ST and KMT test scores (COMB). This region is located a few dozen kilobases upstream of the GATA binding protein 2 (GATA2) gene. GATA2 regulates the development of cochlear hair cells and the inferior colliculus (IC), which are important in tonotopic mapping. The highest probability of linkage was obtained for phenotype SP at 4p14, located next to the region harboring the protocadherin 7 gene, PCDH7. Two SNPs rs13146789 and rs13109270 of PCDH7 showed strong association. PCDH7 has been suggested to play a role in cochlear and amygdaloid complexes. Functional class analysis showed that inner ear and schizophrenia related genes were enriched inside the linked regions. This study is the first to show the importance of auditory pathway genes in musical aptitude. PMID:24614497

  2. The forkhead transcription factor Foxi1 is a master regulator of vacuolar H-ATPase proton pump subunits in the inner ear, kidney and epididymis.

    Directory of Open Access Journals (Sweden)

    Hilmar Vidarsson

    Full Text Available The vacuolar H(+-ATPase dependent transport of protons across cytoplasmic membranes in FORE (forkhead related cells of endolymphatic epithelium in the inner ear, intercalated cells of collecting ducts in the kidney and in narrow and clear cells of epididymis require expression of several subunits that assemble into a functional multimeric proton pump. We demonstrate that expression of four such subunits A1, B1, E2 and a4 all co-localize with the forkhead transcription factor Foxi1 in a subset of epithelial cells at these three locations. In cells, of such epithelia, that lack Foxi1 we fail to identify any expression of A1, B1, E2 and a4 demonstrating an important role for the transcription factor Foxi1 in regulating subunit availability. Promoter reporter experiments, electrophoretic mobility shift assays (EMSA and site directed mutagenesis demonstrate that a Foxi1 expression vector can trans-activate an a4-promoter reporter construct in a dose dependent manner. Furthermore, we demonstrate using chromatin immunoprecipitation (ChIP assays that Foxi1-dependent activation to a large extent depends on cis-elements at position -561/-547 in the a4 promoter. Thus, we provide evidence that Foxi1 is necessary for expression of at least four subunits in three different epithelia and most likely is a major determinant for proper assembly of a functional vacuolar H(+-ATPase complex at these locations.

  3. Visualization of inner ear dysplasias in patients with sensorineural hearing loss. High-resolution MR imaging and volume-rendered reconstructions

    Energy Technology Data Exchange (ETDEWEB)

    Klingebiel, R.; Bockmuehl, U. [Charite CM, Humboldt Univ., Berlin (Germany). Dept. of Radiology; Werbs, M. [Charite CM, Humboldt Univ., Berlin (Germany). ENT Dept.; Freigang, B. [O. von Guericke Univ., Magdeburg (Germany). ENT Dept.; Vorwerk, W. [St. Salvator Krankenhaus, Halberstadt (Germany). ENT Dept.; Thieme, N.; Lehmann, R. [Charite CM, Humboldt Univ., Berlin (Germany). Dept. of Radiology

    2001-11-01

    Purpose: We evaluated a data acquisition and post-processing protocol for inner ear (IE) assessment by MR imaging in patients, suffering from various labyrinth malformations. Material and Methods: MR IE studies of 158 consecutive patients (316 IEs) suffering from sensorineural hearing loss without evidence of an acoustic neurinoma were reviewed for pathologies of the IE and internal acoustic meatus. High-resolution MR data of all abnormal IE studies (n=45) were post-processed to previously standardized 3D volume rendered (VR) reconstructions. Results: In 9 patients (5.7%) the following IE dysplasias were detected: malformation of the cochlea (6 IEs), vestibulum (4 IEs), semicircular canals (12 IEs) and vestibular aqueduct/endolymphatic sac (10 IEs). One patient showed evidence of an aplasia of the vestibulocochlear nerve. In 4 patients multiple IE dysplasias were encountered. Comprehensive 3D visualization of all labyrinthine dysplasias was achieved by the use of two VR reconstructions. The overall time for bilateral IE assessment amounted to 30-35 min. Conclusion: The imaging protocol allows for rapid and comprehensive visualization of various IE dysplasias, based on a limited number of VR reconstructions.

  4. MiR-182-5p protects inner ear hair cells from cisplatin-induced apoptosis by inhibiting FOXO3a

    Science.gov (United States)

    Li, Yimeng; Li, Ao; Wu, Jingfang; He, Yingzi; Yu, Huiqian; Chai, Renjie; Li, Huawei

    2016-01-01

    Cisplatin is widely used for chemotherapy of a variety of malignancies. However, the clinical application of cisplatin is hampered by the resultant irreversible hearing loss due to hair cell apoptosis. To date, no practical regimen to resolve this has been developed. Meanwhile, the role of microRNA in protecting hair cells from cisplatin-induced apoptosis in the inner ear has not been extensively investigated. In this study, we monitored miR-183, -96, and -182 turnover in the cochlea during cisplatin treatment in vitro. We found that overexpression of miR-182, but not miR-183 and -96, improved hair cell survival after 3 μM cisplatin treatment in vitro. We demonstrated that overexpression of miR-182 repressed the intrinsic apoptotic pathway by inhibiting the translation of FOXO3a. Our study offers a new therapeutic target for alleviating cisplatin-induced hair cell apoptosis in a rapid and tissue-specific manner. PMID:27607577

  5. 伴眩晕突发性耳聋患者内耳外淋巴液增强MRI特征%Contrast perilymphatic MRI findings of inner ear in sudden hearing loss with vertigo

    Institute of Scientific and Technical Information of China (English)

    刘颖; 曹代荣; 方哲明; 邢振; 顾晰; 陈曦

    2014-01-01

    Objective To explore the contrast perilymphatic MRI characteristics of inner ears with sudden hearing loss with vertigo.Methods Forty three patients with sudden hearing loss with vertigo and 35 patients with unilateral tinnitus diagnosed by the department of Otolaryngology-Head and Neck Surgery were retrospectively included.Forty eight ears (38 ears with unilateral sudden hearing loss and 10 ears in 5 cases with bilateral sudden hearing loss) were regarded as sudden hearing loss group,35 asymptomatic ears (the opposite ears of the unilateral tinnitus ears) as control group.Thirty eight opposite ears of the 38 unilateral sudden hearing loss ears and 35 ears of the control group showed normal in the pure tone audiometry exam.One hundred and twenty one ears (48 hearing loss ears,38 opposite ears of the 38 unilateral sudden hearing loss ears and the 35 control group's ears) underwent contrast perilymphatic MR exams,0.4 to 0.5 ml gadolinium hydrate diluted with saline was injected through the tympanic membrane,twenty four hours later,three-dimensional fluid attenuated inversion recovery (3D-FLAIR) sequence was performed using a 3.0 T MRI scanner.After the contrast perilymphatic MR exam,success in the exam was judged through the raw image.The signal intensity ratio (SIR) of cochlea basal turn and homolateral brain stem was quantitatively calculated.The SIR difference of 48 ears with sudden hearing loss and 35 asymptomatic ears in control group was analyzed by t test.The SIR difference of the 38 unilateral sudden hearing loss ears and the contralateral asymptomatic ears was also analyzed.The presence of endolymphatic hydrops was judged.Results The contrast perilymphatic MRI of 121 inner ears with intratympanic gadolinium injection were all successful.Endolymphatic hydrops were observed in 12 sudden hearing loss ears with the occurrence rate of 25%(12/48).The SIR of basal turn and homolateral brain stem of the sudden hearing loss ears (2.062±0.907) were lower than the

  6. Ear Tubes

    Science.gov (United States)

    ... ENTCareers Marketplace Find an ENT Doctor Near You Ear Tubes Ear Tubes Patient Health Information News media ... and throat specialist) may be considered. What are ear tubes? Ear tubes are tiny cylinders placed through ...

  7. 内耳出血所致突发性聋患者临床表现特点分析%Clinical features of sudden sensorineural hearing loss accompanied with inner ear hemorrhage

    Institute of Scientific and Technical Information of China (English)

    陈希杭; 林昶; 方哲明; 陈曦; 叶胜难; 程金妹; 张榕

    2015-01-01

    Objective To investigate the clinical features, diagnosis and prognosis of sudden sensorineural hearing loss accompanied with inner ear hemorrhage.Methods Eleven cases of sudden sensorineural hearing loss accompanied with inner ear hemorrhage were retrospectively analyzed, including clinical manifestation, hematological and audiological examinations, as well as characteristics of inner ear three-dimensional fluid-attenuated inversion recovery magnetic resonance imaging (3D-FLAIR MRI).Results Eleven cases of sudden hearing loss with inner ear hemorrhage were accompanied by varying degrees of vertigo, lasting from several minutes to several hours, nine of whom had persistent tinnitus.The audiometry curves of the 11 cases included total deafness or flat descending type.The inner ear 3D-FLAIR MRI studies revealed abnormal high signals at different positions of the inner ear, one case with endolymphatic hydrops.After the treatment, seven cases were invalid, two cases had notable effect, and two cases were effective.Conclusions Abnormal high signals in the inner ear were sensitively detected by 3D-FLAIR MRI sequence, which was applied for the diagnosis of the sudden hearing loss accompanied with inner ear hemorrhage.The effect of conventional treatment was not good and the appropriate treatments for this type of sudden hearing loss need further investigation.%目的 探讨内耳出血所致突发性聋患者的临床特点、诊断方法及预后情况.方法 回顾性分析2010年1月至2014年10月11例考虑为内耳出血所致突发性聋患者的临床资料,包括临床表现、实验室检查、听力学、内耳MRI影像学特征等.结果 11例患者中男5例、女6例,年龄23~73岁(中位年龄44岁);均伴有不同程度的眩晕,持续数分钟至数小时不等,其中9例患者伴有持续性耳鸣;根据听力曲线分型,全聋型9例,平坦下降型2例.11例患者通过三维液体衰减反转恢复(three-dimensional fluid

  8. 大鼠内耳前体细胞的增殖研究%The Precursor Cells from the Inner Ear of SD Rats

    Institute of Scientific and Technical Information of China (English)

    曾亮; 江红群

    2014-01-01

    目的:探讨不同年龄及生长因子对大鼠内耳前体细胞体外增殖的影响。方法①分离取出出生后1天(P1)、7天(P7)、14天(P14)、21天(P21)、30天(P30)、60天(P60)各天龄12只(24耳)SD大鼠的球囊斑、椭圆囊斑、Corti器的前体细胞,在无血清条件下进行单细胞悬浮培养,至第七天,在倒置相差显微镜下对所形成的细胞球进行计数;②取P1大鼠球囊斑、椭圆囊斑、Corti器高增殖细胞分为实验组和对照组,实验组分为四组,培养液分别添加表皮生长因子(epidermal growth factor ,EGF)、碱性成纤维细胞生长因子(basic fibroblast growth factor ,bF-GF)、胰岛素样生长因子-1(insulin-like growth factor -1,IGF -1)、白血病抑制因子(leukemia inhibitory factor , LIF),对照组不加生长因子,观察不同生长因子对细胞球数量的影响;③免疫荧光染色检测细胞球的表型特征。结果①P1SD大鼠内耳各器官单细胞表现为nestin阳性,培养7天后,可形成悬浮的细胞球,球体细胞免疫荧光表现为nestin和BrdU阳性;②耳蜗Corti器只在P1、P7可形成细胞球,而球囊斑、椭圆囊斑各天龄段均可形成细胞球;③培养液中添加EGF、bFGF、IGF-1组,培养形成的细胞球数量明显增多,与对照组比较,差异有显著统计学意义(P<0.01);添加LIF组则与对照组比较差异无统计学意义(P>0.05)。结论大鼠内耳球囊斑、椭圆囊斑以及耳蜗Corti器内有高增殖能力细胞,能表达神经干细胞的特性;随着鼠龄的增长,这种增殖能力总体表现为减退趋势;EGF、bFGF、IGF-1均可单独促进P1大鼠内耳前体细胞的增殖,而LIF无促增殖作用。%Objective To investigate the influence on the proliferation of the precursor cells from the inner ear of SD rats by different ages and growth factors in vitro .Methods The organs of

  9. 磁共振内耳水成像技术及其临床应用价值%Diagnostic value of magnetic resonance imagine technique of inner ear fluid imaging in deaf patients

    Institute of Scientific and Technical Information of China (English)

    习伟; 邢新博; 曹庆; 张毅军; 何建军

    2011-01-01

    目的:探讨磁共振(MRI)内耳水成像技术在临床耳聋患者诊断中的应用价值.方法:60例耳聋患者,采用西门子NOVUS1.5T超导型核磁共振快速自旋回波序列行MR内耳水成像扫描.结果:所有受检者均顺利完成检查,经过多组3D重建技术应用,图像结果可完全达到诊断目的,其中显示内耳畸形8例,结构正常52例.结论:内耳水成像技术能清楚显示内耳膜迷路以及内听道精细解剖结构,可以显示其发育状况及通畅程度,能够为重度耳聋患者的诊断和术前评估提供重要的影像学参数.%Objective: To investigate the MRI technique of the inner ear fluid imaging and its current value ot application in deaf patients. Methods: In sixty deaf patients images of the inner ear fluid were created through fast spin echo using Siemens NOVUS1.5T MRI. Result: Examinations had been completed successfully for all the patients. Through the application of multiple sets of 3D restructure technique, the objectives of the diagnosis could be completely accomplished by the imaging results, with the finding of inner ear malformations in 8 patients, and normal in 52 cases. Conclusion: The MRI technique of the inner ear fluid can clearly show the fine anatomical structure of the inner ear membranous labyrinth and inner auditory canal as well as the developmental status and the extent of fluency, and it can provide important imaging parameters for the diagnosis and preoperative assessment of patients with severe deafness.

  10. Efficient induction of inner ear hair cell-like cells from mouse ES cells using combination of Math1 transfection and conditioned medium from ST2 stromal cells.

    Science.gov (United States)

    Ouji, Yukiteru; Sakagami, Masaharu; Omori, Hiroko; Higashiyama, Shinji; Kawai, Norikazu; Kitahara, Tadashi; Wanaka, Akio; Yoshikawa, Masahide

    2017-08-01

    We sought to establish a more efficient technique for induction of inner ear hair cell-like cells (HC-like cells) from embryonic stem cells (ES cells) by using a combination of two previously reported methods; ST2 stromal cell-conditioned medium, known to be favorable for HC-like cell induction (HIST2 method), and ES cells with transfer of the Math1 gene (Math1-ES cells). Math1-ES cells carrying Tet-inducible Math1 were cultured for 14days with doxycycline in conditioned medium from cultures of ST2 stromal cells following formation of 4-day embryoid bodies (EBs). Although each of the previously introduced methods have been reported to induce approximately 20% HC-like cells and 10% HC-like cells in their respective populations in EB outgrowths at the end of the culture periods, the present combined method was able to generate approximately 30% HC-like cells expressing HC-related markers (myosin6, myosin7a, calretinin, α9AchR, Brn3c), which showed remarkable formation of stereocilia-like structures. Analysis of expressions of marker genes specific for cochlear (Lmod3, Emcn) and vestibular (Dnah5, Ptgds) cells indicated that our HIST2 method may lead to induction of cochlear- and vestibular-type cells. In addition, continuous Math1 induction by doxycycline without use of the HIST2 method preferentially induced cochlear markers with negligible effects on vestibular marker induction. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  11. The variability of inner ear orientation in saurischian dinosaurs: testing the use of semicircular canals as a reference system for comparative anatomy

    Directory of Open Access Journals (Sweden)

    Jesús Marugán-Lobón

    2013-08-01

    Full Text Available The vestibular system of the inner ear houses three semicircular canals—oriented on three nearly-orthogonal planes—that respond to angular acceleration stimuli. In recent years, the orientation of the lateral semicircular canal (LSC has been regularly used to determine skull orientations for comparative purposes in studies of non-avian dinosaurs. Such orientations have been inferred based on fixing the LSC to a common set of coordinates (parallel to the Earth’s horizon, given that the orientation to gravity of this sensory system is assumed constant among taxa. Under this assumption, the LSC is used as a baseline (a reference system both to estimate how the animals held their heads and to describe craniofacial variation among dinosaurs. However, the available data in living birds (extant saurischian dinosaurs suggests that the orientation of the LSC in non-avian saurischian dinosaurs could have been very variable and taxon-specific. If such were the case, using the LSC as a comparative reference system would cause inappropriate visual perceptions of craniofacial organization, leading to significant descriptive inconsistencies among taxa. Here, we used Procrustes methods (Geometric Morphometrics, a suite of analytical tools that compares morphology on the basis of shared landmark homology, to show that the variability of LSC relative to skull landmarks is large (ca. 50° and likely unpredictable, thus making it an inconsistent reference system for comparing and describing the skulls of saurischian (sauropodomorph and theropod dinosaurs. In light of our results, the lateral semicircular canal is an inconsistent baseline for comparative studies of craniofacial morphology in dinosaurs.

  12. The effect of hair bundle shape on hair bundle hydrodynamics of non-mammalian inner ear hair cells for the full frequency range.

    Science.gov (United States)

    Shatz, Lisa F

    2004-09-01

    The effect of the size and the shape of the hair bundle of a hair cell in the inner ear of non-mammals on its motion for the full range of frequencies is determined thereby extending the results of a previous analysis of hair bundle motion for high and low frequencies [Hear Res. 141 (2000) 39-50]. A hemispheroid is used to represent the hair bundle because it can represent a full range of shapes, from thin, pencil-like shapes to wide, flat, disk-like shapes. Boundary element methods are used to approximate the solution for the hydrodynamics. For physiologically relevant parameters, an excellent match is obtained between the model's predictions and measurements of hair bundle motion in the free-standing region of the basilar papilla of the alligator lizard [Aranyosi, Measuring sound-induced motions of the alligator lizard cochlea. Massachusetts Institute of Technology, PhD Thesis, 2002]. Neither in the model's predictions nor in experimental measurements is sharp tuning observed. The model predicted the low frequency region of neural tuning curves for the alligator lizard and bobtail lizard, but could not predict the sharp tuning or the high frequency region. An element that represents an active mechanism is added to the hair bundle model to predict neural tuning curves, which are sharply tuned, and an excellent match is obtained for all the characteristics of neural tuning curves for the alligator lizard, and for the low and high frequency regions for the bobtail lizard. The model does not predict well the sharp tuning of the shorter hair bundles of the bobtail lizard, possibly because it does not represent tectorial sallets.

  13. Mammalian Otolin: a multimeric glycoprotein specific to the inner ear that interacts with otoconial matrix protein Otoconin-90 and Cerebellin-1.

    Directory of Open Access Journals (Sweden)

    Michael R Deans

    Full Text Available The mammalian otoconial membrane is a dense extracellular matrix containing bio-mineralized otoconia. This structure provides the mechanical stimulus necessary for hair cells of the vestibular maculae to respond to linear accelerations and gravity. In teleosts, Otolin is required for the proper anchoring of otolith crystals to the sensory maculae. Otoconia detachment and subsequent entrapment in the semicircular canals can result in benign paroxysmal positional vertigo (BPPV, a common form of vertigo for which the molecular basis is unknown. Several cDNAs encoding protein components of the mammalian otoconia and otoconial membrane have recently been identified, and mutations in these genes result in abnormal otoconia formation and balance deficits.Here we describe the cloning and characterization of mammalian Otolin, a protein constituent of otoconia and the otoconial membrane. Otolin is a secreted glycoprotein of ∼70 kDa, with a C-terminal globular domain that is homologous to the immune complement C1q, and contains extensive posttranslational modifications including hydroxylated prolines and glycosylated lysines. Like all C1q/TNF family members, Otolin multimerizes into higher order oligomeric complexes. The expression of otolin mRNA is restricted to the inner ear, and immunohistochemical analysis identified Otolin protein in support cells of the vestibular maculae and semi-circular canal cristae. Additionally, Otolin forms protein complexes with Cerebellin-1 and Otoconin-90, two protein constituents of the otoconia, when expressed in vitro. Otolin was also found in subsets of support cells and non-sensory cells of the cochlea, suggesting that Otolin is also a component of the tectorial membrane.Given the importance of Otolin in lower organisms, the molecular cloning and biochemical characterization of the mammalian Otolin protein may lead to a better understanding of otoconial development and vestibular dysfunction.

  14. MR内耳水成像在儿童人工耳蜗植入术前评估中的价值%The value of MR hydrography of inner ear in evaluation of children with cochlear implantation

    Institute of Scientific and Technical Information of China (English)

    包杰; 闫昆

    2014-01-01

    Objective To investigate the clinical value of MR hydrography of inner ear in evaluation of children with co-chlear implantation .Methods 24 children with hearing impairment scheduled for cochlear implantation were scanned by use of Siemens Avanto 1 .5 T MRI scanner .The water signal in the region of inner ear was collected and sent to the work-station for image post-processing .Finally ,the imaging manifestations and characteristics were analyzed .Results Of these 24 cases ,18 had normal inner ear morphology ,1 case had cochlear malformation associated with enlarged vestibular aque-duct ,3 cases only had the dilated vestibular aqueduct ,1 case had abnormal semicircular canal ,and ,1 case had Mondini malformation .Conclusion MR hydrography can clearly show the fine anatomical structures of membranous labyrinth and internal auditory canal in the inner ear ,thereby providing important information for the diagnosis of inner ear lesions as well as for the preoperative evaluation for cochlear implantation .%目的:探讨M R内耳水成像在儿童人工耳蜗植入术前评估中的临床应用价值。方法使用Siemens Avanto 1.5 T磁共振扫描仪对24例听觉障碍拟行人工耳蜗植入术的患儿进行扫描,采集内耳所在区域内的水信号,并送后处理工作站进行图像后处理。最后分析其影像学表现及特征。结果24例患者中内耳形态正常18例,耳蜗发育畸形伴前庭导水管扩张1例,单纯前庭导水管扩张3例,半规管异常1例,M o ndini畸形1例。结论 M R内耳水成像技术能清晰显示内耳膜迷路以及内听道精细解剖结构,对于内耳病变的诊断及人工耳蜗植入术的术前评估提供重要信息。

  15. HRCT standardized measurement of the normal anatomic structures of children’s inner ear%儿童内耳正常解剖结构的HRCT标准化测量

    Institute of Scientific and Technical Information of China (English)

    刘军; 李长勤

    2015-01-01

    Objective:The purpose of this study is to provide diagnostic criteria of indistinctive inner ear malformations by HRCT standardized measurements of normal inner ear structures in children. Methods:76 normal children with 152 ears were underwent HRCT of temporal bone. Image were reconstructed by MPR. Two senior radiologists used the double blind means to measure all the image data,including the width,highness of superior semicircular canal (SSCC),lateral semicircular canal (LSCC), posterior semicircular canal (PSCC) cochlea and vestibule. The differences of the above data between the age,different gender, the left and right ears were compared. Results:Width of SSCC bone tube and bone island were (0.87±0.04)mm and (4.54± 0.39)mm,respectively. Width of LSCC bone tube and bone island were (1.50±0.05)mm and (3.06±0.36)mm respectively, PSCC bone tube width and bone leg length were (1.12±0.10)mm and (6.17±0.07)mm,respectively. Cochlea height and length were (4.46±0.11)mm and (8.04±0.16)mm,respectively. Vestibule width and length were (3.38±0.36)mm and (5.68±0.51)mm, respectively. There were no differences between the age,different gender,the left and right ears (t-test,P0.05)。结论:儿童内耳的正常解剖结构在颞骨HRCT图像上可准确测量,不同年龄、性别及左右耳之间的内耳骨性结构无明显差异。

  16. 内耳注入携带 IL -4基因的骨髓间充质干细胞对豚鼠免疫性内耳病基因治疗的研究%Gene Therapy of Inner Ear Injection with Bone -Marrow Mesenchymal Stem Cells Decorated with Interleukin-4 Gene on Immune-Mediated Inner Ear Disease in Guinea Pigs

    Institute of Scientific and Technical Information of China (English)

    郭浪; 谭长强; 刘树森; 江萍; 衡伟伟

    2014-01-01

    目的:研究内耳局部植入白细胞介素4(IL -4)基因修饰骨髓间充质干细胞(bone-marrow mesen-chymal stem cells ,BMSCs)对免疫性内耳病豚鼠内耳病理损伤和听功能的调节与治疗作用。方法采用钥孔嘁血蓝蛋白(KLH)抗原在已致敏的豚鼠圆窗龛局部免疫,制成豚鼠免疫性内耳病模型55只,分为五组:A组(BMSCs载体组)、B组(BM SCs空载体对照组)、C组(重组慢病毒IL -4基因组)、D组(慢病毒空载体对照组)及E组(模拟手术对照组),每组11只,各组均将相应的悬液20μl[BMSCs悬液中含BMSCs(1.5~2.0)×106,慢病毒浓缩液浓度为0.5×108 pfu]经鼓阶开窗植入内耳。采用免疫荧光组织化学试验法、免疫酶组织化学试验法观察IL -4基因产物在内耳组织结构中的分布和表达情况,酶联免疫吸附试验观察血清抗KLH特异性抗体水平,ABR测试听功能变化。结果与免疫前相比,免疫后A、B、C组ABR波Ⅲ阈值不同程度降低,A组阈值降低更明显,差异有统计学意义(P<0.05);免疫组织化学染色显示BMSCs荧光反应阳性细胞主要分布在鼓阶、前庭阶;内耳光镜观察A、B、C组仅在鼓阶内有絮状物,注射部位有少量红细胞和白细胞,D、E组可见不同程度的膜迷路积水,螺旋神经节和蜗轴小血管周围有单个核细胞浸润。结论重组IL -4基因的慢病毒载体可在体外成功转染BM SCs ,经鼓阶途径植入内耳后可在内耳迁移并产生基因产物IL -4,可明显减轻免疫性内耳病动物的内耳免疫炎性反应和听功能损伤,而BMSCs可以作为细胞载体把携带有目的基因的治疗因子迁移到损伤部位而发挥治疗作用。%Objective To evaluate the gene therapeutic effects of guinea pigs model with immune -mediated inner ear disease(IMIED)after locally injection of bone -marrow mesenchymal stem cells(BMSCs) decorated by in

  17. Effect Analysis of Inner Ear Malformations Pre-lingual Deaf Children after Cochlear Implantation*%内耳畸形语前聋患儿人工耳蜗植入术后效果分析*

    Institute of Scientific and Technical Information of China (English)

    钟润兰; 冯永; 管志伟

    2013-01-01

    Objective:To investigate the feasibility of cochlear implantation for inner ear malformations pre-lingual deaf children, and evaluates the rehabilitation effect on hearing and speech after the surgery. Methods:Used cochlear implantation to inner ear mal-formations pre-lingual deaf children, compared with pre-lingual deaf children of normal inner ear structure, recorded the transfer ma-chine T value after the surgery in 1 year, then evaluated and analyzed the rehabilitation effect of hearing and speech, and investigated the satisfaction about the effect of surgery of the patents. Results:There was no significant differences on the test results of hearing and speech and T value between the inner ear in pre-lingual deaf children and those of normal inner ear structure (P>0.05), and most of parents were satisfied with the effect of surgery. Conclusion:After the cochlear implantation, the rehabilitation effect on the hear-ing of inner ear malformation pre-lingual deaf children is great, and no differences from that of pre-lingual deaf children of normal inner ear structure, which is worth promotion.%  目的:探讨内耳畸形语前聋患儿人工耳蜗植入术的可行性,并对其术后听觉言语康复效果进行评估。方法:对内耳畸形的语前聋患儿进行人工耳蜗植入术,并与内耳结构正常的语前聋患儿比较,记录术后1年的调机T值,评估和分析其术后听觉言语康复效果,并调查患儿家长对术后效果的满意度。结果:内耳畸形的语前聋患儿的术后听力及言语测试结果、调机T值等与内耳结构正常的患儿比较无显著性差异(P>0.05),且多数患儿家长对手术效果感到满意。结论:内耳畸形语前聋患儿行人工耳蜗植入术后,听觉康复效果显著,与内耳结构正常的语前聋患儿无明显差别,值得临床推广。

  18. Value of multi-slice CT in patients with congenital inner ear malformation before cochlear implantation%多层螺旋CT在内耳畸形的人工耳蜗植入术前评估中的价值

    Institute of Scientific and Technical Information of China (English)

    吴琛; 熊玉伟; 周运锋

    2015-01-01

    目的:探讨多层螺旋CT在患有内耳畸形的人工耳蜗植入术前评估中的价值。方法:搜集我院因听力障碍拟行人工耳蜗植入的患者34例,所有患者均行多层螺旋CT检查。结果:34例患者中患内耳畸形的有10例共19耳,多数病耳合并多种畸形,其中耳蜗畸形8耳,前庭导水管扩大畸形8耳,前庭、半规管畸形4耳,内听道发育异常3耳。结论:多层螺旋CT扫描结合后处理技术可以更加准确地对内耳畸形做出诊断,在人工耳蜗植入术前具有重要的指导价值。%Objective:To evaluate the value of multi-slice CT in patients with congenital inner ear malformation before cochlear implantation .Methods:Multi-slice CT was performed in 34 patients with hearing impairment before cochlear implantation .Results:In 34 patients,inner ear malformation was de-tected in 10(19 ears),and more cases were complicated with multiple malformations,in which 8 cases were cochlear malformations,8 enlarged vestibular aqueduct malformation,4 vestibule and semi-circular canal malformations,and 3 internal auditory cannal malformations.Conclusion:Multi-slice CT can make accurate diagnosis of congenital inner ear malformations before cochlear implantation .

  19. 磁共振内耳水成像在人工耳蜗植入术中的应用价值分析%Application value of Magnetic Resonance Hydrography of Inner Ear Imaging in Cochlear Implantation

    Institute of Scientific and Technical Information of China (English)

    王全; 周航; 朱琳; 姜洪; 孙臣义; 宋长悦

    2015-01-01

    目的:探讨磁共振内耳水成像在人工耳蜗植入术中的应用价值。方法筛选2012年1月至2014年1月于我院进行人工耳蜗植入术患者146例,作为研究对象。于手术治疗前进行头颅内听道MRI及螺旋CT检查,对所有影像学结果进行分析总结及统计学处理,探讨MRI内耳水成像在人工耳蜗植入术中的应用价值。结果146例患者中(行双侧检查共292耳),其中MRI检出前庭导水管异常13例(20耳),CT检出5例;MRI检出内耳畸形15例(19耳), CT检出11例,漏诊4例;MRI检出内听道狭窄5例(8耳),CT检出2例,漏诊3例;MRI检出耳蜗纤维化4例(5耳),CT检出4例(4耳);单纯依据CT检查诊断正确率为77.40%(113/146),单纯依据MRI检查诊断正确率为93.84%(137/146)。结论 MRI水成像技术可应用于人工耳蜗植入术前的影像评价,可提供准确、可靠的内耳膜迷路及内听道神经的解剖学信息,可对耳蜗纤维化、神经发育等诊断提供准确依据,对治疗方案的选择具有指导性意义。%Objective To explore the application value of magnetic resonance hydrography of inner ear imaging in cochlear implantation.Methods 146 patients underwent cochlear implantation in our hospital were selected from January 2012 to January 2014 as the research objects. Internal auditory canal MRI and CT were performed before the surgery. All the imaging data was analyzed and statistically summarized. The application value of magnetic resonance hydrography of inner ear imaging in cochlear implantation were explored.Results Of all the 146 cases(292 ears), 13 cases(20 ears) were detected with vestibular aqueduct abnormality by MRI and 5 cases by CT; 15 cases(19 ears) were detected with inner ear malformations by MRI and 11 cases by CT with 4 cases of missed diagnosis. 5cases (8 ears) were detected with internal auditory canal stenosis by MRI and 2 cases by CT with 3 cases of missed diagnosis. 4 cases(5 ears) were

  20. Cauliflower Ear

    Science.gov (United States)

    ... dientes Video: Getting an X-ray What's Cauliflower Ear? KidsHealth > For Kids > What's Cauliflower Ear? Print A A A Have you ever seen someone whose ear looks bumpy and lumpy? The person might have ...

  1. Ear barotrauma

    Science.gov (United States)

    Barotitis media; Barotrauma; Ear popping - barotrauma; Pressure-related ear pain; Eustachian tube dysfunction - barotrauma ... The air pressure in the middle ear is most often the same as the air ... body. The Eustachian tube is a connection between the middle ...

  2. Swimmer's ear

    Science.gov (United States)

    ... worse when you pull on the outer ear Hearing loss Itching of the ear or ear canal ... reduce itching and inflammation Pain medicine, such as acetaminophen (Tylenol) or ibuprofen (Advil, Motrin) Vinegar (acetic acid) ...

  3. Ear wax

    OpenAIRE

    Browning, George GG

    2008-01-01

    Ear wax only becomes a problem if it causes a hearing impairment, or other ear-related symptoms. Ear wax is more likely to accumulate and cause a hearing impairment when normal extrusion is prevented — for example, by hearing aids, or by the use of cotton buds to clean the ears.Ear wax can visually obscure the ear drum, and may need to be removed for diagnostic purposes.

  4. Comparação morfométrica da orelha interna entre ovinos e humanos através da tomografia computadorizada CT-Scan sheep and human inner ear morphometric comparison

    Directory of Open Access Journals (Sweden)

    Valter Ayres Seibel

    2006-06-01

    Full Text Available INTRODUÇÃO: trabalhos sobre o uso de ovelhas em cirurgias experimentais e treinamento em cirurgia otológica são raros. Este estudo pretende contribuir para ampliar o conhecimento nessa área. OBJETIVO: Estudar a orelha interna da ovelha por meio de tomografia computadorizada e cortes sucessivos com o intuito de apresentar dados morfométricos mais precisos relacionados à comparação entre a orelha de ovelhas e a de humanos. MATERIAL E MÉTODO: Foi realizado um estudo descritivo sem seguimento no qual foram comparadas as estruturas da orelha interna da ovelha com as dos humanos. As medidas foram obtidas através de tomografias computadorizadas e avaliadas por meio de um programa de análise de imagens médicas (Osíris 4.16. RESULTADOS: O estudo morfológico da orelha da ovelha, em média, e da orelha humana, em média, revelaram grande similaridade de anatomia. A maior parte das estruturas (10 de 15 preservou a relação proposta de 2/3 da dimensão humana em relação à dimensão ovina. CONCLUSÃO: Os achados contribuem para uso da orelha da ovelha como modelo em cirurgia experimental e treinamento em cirurgia otológica.INTRODUCTION: Studies about the use of sheep in surgical training and experimental otologic surgery are rare. This study intends to contribute to the knowledge on this field. AIM: To study sheep inner ear structures using computerized tomography and serial cross-sections to collect more accurate morphometric data to compare sheep and human ears. MATERIAL AND METHODS: This descriptive study compared the inner structures of sheep and human ears. Measurements were made using computerized tomography, and they were stored in a DICOM compact disc for later analysis and manipulation, with a program used for medical image analysis (Osíris 4.16. RESULTS: Mean measures for sheep and human ears were found to be similar in this morphological study. Most structures (10 out of 15 maintained the 2/3 ratio of sheep to human ear

  5. Ear Pieces

    Science.gov (United States)

    DiJulio, Betsy

    2011-01-01

    In this article, the author describes an art project wherein students make fanciful connections between art and medicine. This project challenges students to interpret "ear idioms" (e.g. "blow it out your ear," "in one ear and out the other") by relying almost entirely on realistic ear drawings, the placement of them, marks, and values. In that…

  6. Ear trauma.

    Science.gov (United States)

    Eagles, Kylee; Fralich, Laura; Stevenson, J Herbert

    2013-04-01

    Understanding basic ear anatomy and function allows an examiner to quickly and accurately identify at-risk structures in patients with head and ear trauma. External ear trauma (ie, hematoma or laceration) should be promptly treated with appropriate injury-specific techniques. Tympanic membrane injuries have multiple mechanisms and can often be conservatively treated. Temporal bone fractures are a common cause of ear trauma and can be life threatening. Facial nerve injuries and hearing loss can occur in ear trauma.

  7. RELACIÓN ENTRE LOS TRASTORNOS POR ANSIEDAD Y ALTERACIONES DEL OÍDO INTERNO Relationship between anxiety disorders and disorders of the inner ear

    Directory of Open Access Journals (Sweden)

    Heydy Luz Chica Urzola

    2010-01-01

    Full Text Available La ansiedad es un proceso normal adaptativo a circunstancias que generan estrés o representan un desafío para quien la padece y puede tornarse en desadaptativa bajo algunas circunstancias. Como parte del espectro sintomático de la ansiedad, algunas de sus representaciones somáticas se relacionan con equilibrio y oído interno. Con frecuencia se encuentra relación entre la sintomatología neuropsiquiátrica y otorrinolaringológica. Las estadísticas internacionales así lo señalan. En Colombia no hay datos específicos al respecto, aunque se encuentra información de patologías individuales. El abordaje de estos pacientes debe ser integral, y con disposición de la mayor cantidad de información clínica y paraclínica posible según la sospecha diagnóstica y con el paciente, se establecen indicadores de logros reales según el caso. La causalidad o el orden de aparición de la sintomatología entre la eminentemente psiquiátrica y la otológica es variable y en muchos casos parece circular. El ver estos síntomas desde la psiquiatría o desde la otorrinolaringología es un abordaje con frecuencia insuficiente y requiere de la integración de saberes. Con ese fin se han planteado teorías explicativas en varios sentidos e incluso se han adicionado categorías diagnósticas nuevas. El tratamiento es un abanico de posibilidades que incluye la terapia física de acondicionamiento y rehabilitación vestibular, psicoterapia y farmacoterapia, dentro de la cual se recomienda el uso de inhibidores selectivos de la recaptación de serotonina.The anxiety is a normal process adjusts at circumstances that generate discomfort or declares a challenge for who is a victim of it and it can turn in adaptsless in some circumstances. Within of the discomfort indicative of anxiety, some of the symptoms have relationship with balance and inner ear. Frequently it is find relation between the symptomatology neuropsychiatric and otoryinologist. International

  8. CBA小鼠内耳感觉上皮的参考数据%Reference data of sensory epithelium in the inner ear in CBA mice

    Institute of Scientific and Technical Information of China (English)

    刘洪; 丁大连; 孙虹; 蒋海燕; RichardSalvi

    2011-01-01

    Objective To provide useful reference data of sensory epithelium in the inner ear, the cochlear and vestibular system were carefully measured in CBA mice. Methods Six young CBA mice at three months of age were used for this study. The surface preparations of cochlear basilar membrane and vestibular end-organs were measured under light microscope. The length and the width of basilar membrane and organ of Corti were examined along the cochlear basilar membrane. In addition, the total number and the density of cochlear hair cell along the basilar membrane were also calculated. To evaluate the vestibular end-organs, the total amount of hair cells in macula of saccule and utricle were counted. The hair cell density of striola region and marginal region in saccule and utricle were calculated respectively, and the density of hair cells in cristae in membranous ampulla of three semicircular canals were also counted. Results The total length of the cochlear basilar membrane was 5.76 ±0.196 mm in CBA mice. The width of basilar membrane was 339.1 ±9.87 μm at 1.5 mm, 304.5 ± 11.82 μm at 3 mm, and 300.1 ±7.22μm at 5 mm from the cochlear base respectively. This indicated that the width of cochlear basilar membrane was gradually narrowing from base to apex. In contrast, the width of organ of Corti was 37.80±2.24 μm at 1.5 mm, 45.00±2.67μm at 3 mm, and 52.20 ± 3.16 fun at 5 mm from the base respectively, which demonstrated that the width of organ of Corti was gradually increasing from base to apex. The total number of cochlear hair cells in CBA mice was 3116.41 ± 151.91, which included 680.67 ± 17.50 inner hair cells and 2435.8 ± 143.46 outer hair cells. The density of cochlear hair cells was similar across the entire length of the cochlea with a density of 541.1 ± 9.36/mm. The density of inner hair cells and outer hair cells were 118.3±2.68/mm and 422.8 ± 11.87/mm respectively. The total number of hair cells in macula of utricle and saccule were 3300 ± 177

  9. SOX10 mutation is relevant to inner ear malformation in patients with Waardenburg syndrome%SOX10基因突变对Waardenburg综合征患者内耳发育的影响

    Institute of Scientific and Technical Information of China (English)

    徐广雨; 郝青青; 钟玲玲; 任巍; 闫艳; 刘日渊; 李佳楠; 郭维维; 赵辉

    2016-01-01

    目的 通过对SOX10基因突变Waardenburg综合征(Waardenburg syndrome,WS)患者的内耳影像学分析和分子遗传学分析,研究SOX10基因突变与WS患者发生内耳畸形的相关性.方法 收集2001-2015年解放军总医院耳鼻咽喉头颈外科收治的WS患者36例的临床资料.通过颞骨高分辨率CT、头颅MRI、内听道磁共振水成像等影像学检查,全面评估每位患者内耳发育情况.并对每位患者筛查WS常见致病基因SOX10、MITF、PAX3的突变情况.按SOX10基因是否突变分为2组,以Fisher精确检验法比较两组间内耳畸形发生率的差异.结果 36例WS患者中,共发现12例内耳畸形(33.3%),其中后半规管畸形发生率最高(12例),可合并前庭扩大及耳蜗畸形.36例患者中9例检出SOX10基因杂合突变,其中6例出现双侧内耳畸形.36例患者中27例无SOX10基因突变,其中6例出现双侧内耳畸形.Fisher精确检验法比较SOX10基因突变组与非SOX10基因突变组间内耳畸形发生率差异有统计学意义(P =0.036).结论 WS患者中如为SOX10基因突变,则出现内耳畸形的可能性较大,并且趋向于双侧耳蜗、前庭及半规管同时畸形.%Objective To determine the relevance between the SOX10 mutation and Waardenburg syndrome (WS) accompanied with inner ear abnormality by analyzing the inner ear imaging results and molecular and genetic results of the WS patients with the SOX10 mutation.Methods This study included 36 WS in patients during 2001 and 2015 in the department of otorhinolaryngology head and neck surgery,Chinese Peoples's Liberation Army General Hospital.The condition of the inner ear of each patient was assessed by analyzing HRCT scans of the temporal bone and MRI scans of the brain and internal auditory canal.Meanwhile,the possible pathogenic genes of WS,including SOX10,MITF,and PAX3,were also screened.Patients were divided into two groups according to SOX10 mutation.The Fisher accuracy test was used to determine

  10. Ear Problems in Swimmers

    Directory of Open Access Journals (Sweden)

    Mao-Che Wang

    2005-08-01

    Full Text Available Acute diffuse otitis externa (swimmer's ear, otomycosis, exostoses, traumatic eardrum perforation, middle ear infection, and barotraumas of the inner ear are common problems in swimmers and people engaged in aqua activities. The most common ear problem in swimmers is acute diffuse otitis externa, with Pseudomonas aeruginosa being the most common pathogen. The symptoms are itching, otalgia, otorrhea, and conductive hearing loss. The treatment includes frequent cleansing of the ear canal, pain control, oral or topical medications, acidification of the ear canal, and control of predisposing factors. Swimming in polluted waters and ear-canal cleaning with cotton-tip applicators should be avoided. Exostoses are usually seen in people who swim in cold water and present with symptoms of accumulated debris, otorrhea and conductive hearing loss. The treatment for exostoses is transmeatal surgical removal of the tumors. Traumatic eardrum perforations may occur during water skiing or scuba diving and present with symptoms of hearing loss, otalgia, otorrhea, tinnitus and vertigo. Tympanoplasty might be needed if the perforations do not heal spontaneously. Patients with chronic otitis media with active drainage should avoid swimming, while patients who have undergone mastoidectomy and who have no cavity problems may swim. For children with ventilation tubes, surface swimming is safe in a clean, chlorinated swimming pool. Sudden sensorineural hearing loss and some degree of vertigo may occur after diving because of rupture of the round or oval window membrane.

  11. Ear problems in swimmers.

    Science.gov (United States)

    Wang, Mao-Che; Liu, Chia-Yu; Shiao, An-Suey; Wang, Tyrone

    2005-08-01

    Acute diffuse otitis externa (swimmer's ear), otomycosis, exostoses, traumatic eardrum perforation, middle ear infection, and barotraumas of the inner ear are common problems in swimmers and people engaged in aqua activities. The most common ear problem in swimmers is acute diffuse otitis externa, with Pseudomonas aeruginosa being the most common pathogen. The symptoms are itching, otalgia, otorrhea, and conductive hearing loss. The treatment includes frequent cleansing of the ear canal, pain control, oral or topical medications, acidification of the ear canal, and control of predisposing factors. Swimming in polluted waters and ear-canal cleaning with cotton-tip applicators should be avoided. Exostoses are usually seen in people who swim in cold water and present with symptoms of accumulated debris, otorrhea and conductive hearing loss. The treatment for exostoses is transmeatal surgical removal of the tumors. Traumatic eardrum perforations may occur during water skiing or scuba diving and present with symptoms of hearing loss, otalgia, otorrhea, tinnitus and vertigo. Tympanoplasty might be needed if the perforations do not heal spontaneously. Patients with chronic otitis media with active drainage should avoid swimming, while patients who have undergone mastoidectomy and who have no cavity problems may swim. For children with ventilation tubes, surface swimming is safe in a clean, chlorinated swimming pool. Sudden sensorineural hearing loss and some degree of vertigo may occur after diving because of rupture of the round or oval window membrane.

  12. Classification and diagnosis of ear malformations

    Directory of Open Access Journals (Sweden)

    Bartel-Friedrich, Sylva

    2007-01-01

    Full Text Available In the ENT region 50% of the malformations affect the ear. Malformations of the outer and middle ear are predominantly unilateral (ca. 70-90% and mostly involve the right ear. Inner ear malformations can be unilateral or bilateral. The incidence of ear malformations is approximately 1 in 3800 newborns. Ear malformations may be genetic (associated with syndromes or not, with family history, spontaneous mutations or acquired in nature. Malformations can affect the outer ear (pinna and external auditory canal, EAC, middle ear and inner ear, not infrequently in combination. Formal classification is advisable in order to be able to predict the prognosis and compare treatment schedules. Various classifications have been proposed: pinna and EAC malformations according to Weerda [1], middle ear malformations according to Kösling [2], and inner ear malformations according to Jackler [3], [4], to Marangos [5] and to Sennaroglu [6]. Additionally, we describe Altmann’s classification of atresia auris congenita [7] and the Siegert-Mayer-Weerda score [8] for EAC and middle ear malformations, systems of great practicability that are in widespread clinical use. The diagnostic steps include clinical examination, audiological testing, genetic analysis and, especially, CT and MRI. These imaging methods are most usefully employed in combination. Precise description of the malformations by means of CT and MRI is indispensable for the planning and successful outcome of operative ear reconstruction and rehabilitation procedures, including cochlear implantation.

  13. Ear Tumors

    Science.gov (United States)

    ... Japanese Espaniol Find information on medical topics, symptoms, drugs, procedures, news and more, written in everyday language. * This is ... the Ears, Nose, and Throat Additional Content Medical News Ear Tumors ... NOTE: This is the Consumer Version. DOCTORS: Click ...

  14. Ear Disorders

    Science.gov (United States)

    ... You use all of them in hearing. Sound waves come in through your outer ear. They reach your middle ear, where they make your eardrum vibrate. The vibrations are transmitted through three tiny bones, called ossicles, ...

  15. Elephant ear

    Science.gov (United States)

    ... Supplements Videos & Tools Español You Are Here: Home → Medical Encyclopedia → Elephant ear URL of this page: //medlineplus.gov/ency/article/002867.htm Elephant ear To use the sharing features on this page, please enable JavaScript. Elephant ear plants are indoor or outdoor plants with very large, ...

  16. The Role of Estrogen and Estrogen Receptors in the Development and Function of Inner Ear%雌激素及其受体在内耳发育和功能上的作用

    Institute of Scientific and Technical Information of China (English)

    杨利平; 吴耀松; 刘辉; 陈玉龙

    2012-01-01

    雌激素在生殖系统、认知记忆系统、骨骼和神经的发育及其功能维持等多种生理功能中扮演了重要的作用.近年来,在内耳发育及其功能研究过程中,许多学者发现在听力和平衡系统功能上的性别差异可能归根因于不同性别的雌激素水平差异.这些研究表明,雌激素及其受体在内耳发育、听力和平衡系统功能维持上也具有重要作用.该文用一个新的视角聚焦于雌激素及其受体在内耳发育和功能上的研究进展.该综述能为进一步研究雌激素在听力和平衡系统中的作用机制及相关疾病的临床治疗提供参考.%The sex hormone estrogen is a hormonal multi-tasker, contributing to roles as diverse as the differentiation and function of the reproductive tract, memory storage, bone growth and nerve system. In recent years, in the investigation on the development and function of inner ear, many authors have shown a gender difference in hearing function and some of them implied that part of this variation was due to the difference in estrogen levels between females and males. These studies suggested that estrogen and estrogen receptors have an effect on the development of inner ear, hearing and vestibular functions. This paper focus on the investigation progress of estrogen and estrogen receptors in the development and function of inner ear from a novel perspective and provides a reference for the further study of estrogen role in the mechanism of hearing and balance systems and clinical therapy of related diseases.

  17. 涤痰定眩汤治疗内耳眩晕症30例临床观察%Clinical observation on treating vertigo inner ear disease with the Ditan Dingxuan decoction

    Institute of Scientific and Technical Information of China (English)

    樊小平

    2012-01-01

      目的:探讨涤痰定眩汤治疗内耳眩晕症的临床疗效.方法:依据诊断标准收治内耳眩晕症患者60例,并随机抽取30例作为对照组,治疗组30例采用中药祛风化痰、祛瘀利水治其标,滋肝养肾、温补脾阳治其本,口服“涤痰定眩汤”剂,配合使用盐酸氟桂嗪;对照组用盐酸氟桂嗪治疗.结果:治疗组30例中,总有效28例,有效率为93.3%;对照组30例,总有效24例,有效率为80.0%.结论:中西药结合使用治疗内耳眩晕症在疗效上明显优于西药治疗,且复发率低.%  Objective: To investigate the clinical efficacy of treating vertigo inner ear disease with the Ditan Dingxuan decoction. Methods: Admitted to 60 patients with vertigo inner ear disease according to diagnostic criteria, and they were randomly divided into control group and treatment group, 30 cases in each group, treatment group was treated with TCM expelling wind and phlegm, blood stasis and benefits of water to treat the symptoms, nourish liver and Yang Shen, Wenbu Piyang to treat the basic, oral “the Ditan Dingxuan decoction” agent, plus the use of hydrochloric acid flunarizine; the control group was treated with flunarizine. Results: The total effective number of cases was 28 cases in treatment group, the effective rate was 93.3%; the total effective number of cases was 24 cases in control, the total effective rate was 80.0%. Conclusion: The effect of treating treating vertigo inner ear disease in the integrative medicine was better, low recurrence rate.

  18. Effect of auditory enlightenment and whole ability training in hearing impaired children with inner ear malformations%内耳发育畸形听障患儿听能启蒙与整体能力培建效果

    Institute of Scientific and Technical Information of China (English)

    李海珍; 郑秀瑾; 黄东生; 张趁; 魏红; 张文露; 孙雪萍

    2014-01-01

    Objective To explore the methods of auditory enlightenment and whole ability training in severe hearing impaired children with inner ear malformations and growth retardation .Methods Eleven severe hearing impaired children with inner ear malformations were chosen , and received the methods of multiple stimuli including auditory, vision, tactile sensation, large and fine motor and so on in order to train their skills including the response and discrimination of sounds , language , and cognition and so on .Results The abilities of hearing and sense were gradually establishment in children 3 months after the training .Seven children could perceive clearly sound , and finish the hearing examination after training 6-13 months so as to lay the foundation for behavioral responses after the cochlear implantation surgery .Two children finished the hearing assessment after the hearing compensation through the audiphone .Conclusions The methods of multiple stimuli in the different sense at the same time can promote the formation of auditory consciousness and auditory nerve loop in infants with inner ear malformations .%目的:探讨内耳发育畸形且伴运动发育落后的极重度听障婴幼儿听觉能力启蒙与整体能力培建方法。方法选择内耳发育畸形极重度听障婴幼儿11例,采用听觉、视觉、触觉、大运动、精细运动等多种刺激并用的方法,对被试大脑皮层感应与运动发育进行康复训练,培建其对声音的反应和辨别能力,以及语言、认知等技能。结果11例患儿训练3个月后,听感知能力逐渐建立;6~13个月后7例感知声音明确,完成行为听力检查,为人工耳蜗植入手术后调机的行为反应奠定基础;2例在助听器补偿听力后完成听觉评估。结论以多感官同时刺激的方式对内耳发育畸形小龄婴幼儿的听觉意识及听神经回路的形成有促进作用。

  19. Deafness Gene Screening for Patients with Inner Ear Malformation Except from EVA%不伴前庭导水管扩大内耳发育畸形患者的基因筛查研究

    Institute of Scientific and Technical Information of China (English)

    王剑; 梁鹏飞; 王淑娟; 查定军; 陈阳; 邱建华

    2015-01-01

    Objective Mutations in SLC26A4 have been proved by many researchers as the main genetic factor of enlarged vestibular aqueduct (EVA) and temporal bone deformities with EVA. In this study, 12 unrelated patients with inner ear malformations without EVA were assessed to explore the genetic pathogenesis of inner ear malformation.Methods Twelve patients with inner ear malformations excluding EVA participated in this study. Inner ear malformations were evaluated by temporal bone CT scan and inner ear MRI. All DNAs was extracted from peripheral blood leukocytes. The whole coding regions of SLC26A4 and GJB2 gene were directly sequenced. Meanwhile, two cases received a hearing loss related gene screening, including 51 hearing loss related genes.ResultsWe have detected the heterozygosis mutation in SLC26A4 gene (c.2219G>T, rs111033310) in one patient, and the heterozygosis mutation in GJB2 gene (c.235delC) in one patient. The gene chip screeing has found 3 rare heterozygosis mutations in CDH23 gene (rs181658753), STRC gene (rs143613180) and WFS1 gene (rs142651446) in one patient, and 2 novel heterozygosis missense mutations in TRIOBP gene (c.6196G>A, p.Glu2066Lys) and LOXHD gene (c.1261C>T, p. Arg421Trp) and one heterozygosis splice mutation in ESRRB gene (c.1057+8C>T) in the other one.Conclusion In this study, we have identified some rare or novel mutations in 6 genes. More should be studied regarding the mutations. This result indicates that there may be some other genes involved in inner ear malformations with (or without) environmental factors, thus requiring further research.%目的: SLC26A4基因突变已被证实与前庭导水管扩大及其相关的内耳发育畸形密切相关。本研究对12例不合并前庭导水管扩大的内耳畸形耳聋患者进行基因筛查,以明确其可能的致病相关基因。方法所有患者均通过颞骨CT及内听道MRI明确其内耳发育畸形特征。知情同意后采集患者外周血基因组DNA,对SLC26A4

  20. Analysis of Auditory Perception Skills in Pre - lingual Deaf Children with Inner Ear Malformation after Cochlear Implantation%内耳畸形语前聋患儿人工耳蜗植入术后听觉能力分析

    Institute of Scientific and Technical Information of China (English)

    陈秀兰; 秦兆冰; 张玉玲; 付凯辉

    2015-01-01

    Objective The aim of this study was to evaluate the outcomes of auditory perception skills after cochlear implantation in children with malformed inner ear and compare them with a group of congenitally deaf chil ‐dren implantees with a normal inner ear .Methods 21 children with inner ear malformation were retrospective stud‐ied .There were 9 cases with large vestibular aqueduct syndrome (LVAS) ,7 with Mondini abnormality ,5 with com‐mon cavity .The postoperative outcomes of these 21 cases were compared with 21 cases with normal inner ear struc‐ture .The outcomes of all the children after the surgery in 1 year were studied using the soundfield test in frequency ranging 0 .5 to 4 kHz and the auditory perception skills ,and the auditory perception skills consisted of natural envi‐ronmental sound recognition ,consonants recognition ,vowels recognition ,numeral recognition ,tone recognition , monosyllabe recognition ,disyllabe recognition ,trisyllabe recognition ,short sentences recognition ,selective hearing recognition .Results The results of soundfield test and auditory perception skills after cochlear implantation in 9 children with LVAS and 6 with Mondini abnormality had no significant difference (P > 0 .05) comparing with the control cases .Postoperative thresholds in soundfield test were 50 ~ 75 dB HL for 1 case with severe Mondini abnor‐mality ,the mean value of hearing ability score was 70 .5% ,and less than the results of control cases .Postoperative mean thresholds in soundfield test were 65 .26 ± 5 .13 dB HL for 5 cases with common cavity ,the hearing ability score was less than the results of control cases (P< 0 .05) .Conclusion The effect of rehabilitation had no difference between the children with LVAS and the cases with normal inner structure after cochlear implantation ,but was poo‐rer in children with severe Mondini abnormality and common cavity .It was necessary to evaluate the degree of mal‐formation of inner ear structure before

  1. Ear Problems

    Science.gov (United States)

    ... have cold or flu symptoms?YesNoDo you have tooth pain on the same side as the ear pain ... or 2 days, see your doctor.Start OverDiagnosisA tooth problem can radiate pain to the ear on the same side.Self ...

  2. Investigation of SLC26A4 Mutations Associated with inner ear malformations%内耳畸形相关SLC26A4基因的研究

    Institute of Scientific and Technical Information of China (English)

    朱庆文; 臧雯; 袁永一; 韩海霞; 张喜琴; 蒋新霞; 任秀敏; 冯彩红; 路虹

    2012-01-01

    Objective: To study the molecular pathogenesis of SLC26A4 mutations associated with inner ear malformations including large vestibular aqueduct syndrome (LVAS), Mondini dysplasia and inner ear malforma-tions but not accompanied with I.VAS. Method:DNA sample and clinical material were obtained from 14 sporadic LVAS probands.six Mondini dysplasia probands and seven inner ear malformations excluding LVAS probands. SI.C26A4 Rene mutation was analyzed by direct sequencing for its 20 coding exons. GJB2 gene and also mtl2SrRNA were analyzed by direct sequencing. Result:In 14 cases of LVAS, two mutations were detected in 12 patients(85. 7%, either homozygous or compound heterozygous mutations), and one mutation was found in two patients(14. 3%). In six cases of Mondini dysplasia, two mutations were detected in all of patients( 100%). No mutation could be found in the seven cases of other inner ear abnormalities not accompanied with LVAS. No patho-genic mutation was detected in all of these 27 probands in GJB2 gene and mtl2SrRNA 1555/1494T. Conclusion: We have shown that LVAS and Mondini dysplasia closely correlate with SLC26A4 gene. No mutation was detected in seven probands of inner ear malformations not accompanied with LVAS. We should study the molecular pathoge-nesis of this disease in depth.%目的:研究内耳畸形相关SLC26A4基因在大前庭水管综合征(LVAS)、Mondini畸形及不伴前庭水管扩大的耳蜗畸形耳聋人群中的突变情况,在分子水平上探讨内耳畸形的发病机制,为基因诊断提供理论基础.方法:收集14例散发LVAS、6例Mondini畸形(伴前庭水管扩大)及7例不伴前庭水管扩大的耳蜗畸形耳聋患者的外周血DNA样本及临床资料,利用PCR扩增目的基因后直接测序的方法对所有患者进行SLC26A4基因全编码序列检测,同时进行GJB2、线粒体12SrRNA 1555/1494位点排除性检测.结果:14例LVAS患者中12例(85.7%)具有SLC26A4双等位基

  3. Listening to the ear

    Science.gov (United States)

    Shera, Christopher A.

    Otoacoustic emissions demonstrate that the ear creates sound while listening to sound, offering a promising acoustic window on the mechanics of hearing in awake, listening human beings. That window is clouded, however, by an incomplete knowledge of wave reflection and transmission, both forth and back within the cochlea and through the middle ear. This thesis "does windows," addressing wave propagation and scattering on both sides of the middle ear. A summary of highlights follows. Measurements of the cochlear input impedance in cat are used to identify a new symmetry in cochlear mechanics-termed "tapering symmetry" after its geometric interpretation in simple models-that guarantees that the wavelength of the traveling wave changes slowly with position near the stapes. Waves therefore propagate without reflection through the basal turns of the cochlea. Analytic methods for solving the cochlear wave equations using a perturbative scattering series are given and used to demonstrate that, contrary to common belief, conventional cochlear models exhibit negligible internal reflection whether or not they accurately represent the tapering symmetries of the inner ear. Frameworks for the systematic "deconstruction" of eardrum and middle-ear transduction characteristics are developed and applied to the analysis of noninvasive measurements of middle-ear and cochlear mechanics. A simple phenomenological model of inner-ear compressibility that correctly predicts hearing thresholds in patients with missing or disarticulated middle-ear ossicles is developed and used to establish an upper bound on cochlear compressibility several orders of magnitude smaller than that provided by direct measurements. Accurate measurements of stimulus frequency evoked otoacoustic emissions are performed and used to determine the form and frequency variation of the cochlear traveling-wave ratio noninvasively. Those measurements are inverted to obtain the spatial distribution of mechanical

  4. Vascular development in the retina and inner ear: control by Norrin and Frizzled-4, a high-affinity ligand-receptor pair.

    Science.gov (United States)

    Xu, Qiang; Wang, Yanshu; Dabdoub, Alain; Smallwood, Philip M; Williams, John; Woods, Chad; Kelley, Matthew W; Jiang, Li; Tasman, William; Zhang, Kang; Nathans, Jeremy

    2004-03-19

    Incomplete retinal vascularization occurs in both Norrie disease and familial exudative vitreoretinopathy (FEVR). Norrin, the protein product of the Norrie disease gene, is a secreted protein of unknown biochemical function. One form of FEVR is caused by defects in Frizzled-4 (Fz4), a presumptive Wnt receptor. We show here that Norrin and Fz4 function as a ligand-receptor pair based on (1) the similarity in vascular phenotypes caused by Norrin and Fz4 mutations in humans and mice, (2) the specificity and high affinity of Norrin-Fz4 binding, (3) the high efficiency with which Norrin induces Fz4- and Lrp-dependent activation of the classical Wnt pathway, and (4) the signaling defects displayed by disease-associated variants of Norrin and Fz4. These data define a Norrin-Fz4 signaling system that plays a central role in vascular development in the eye and ear, and they indicate that ligands unrelated to Wnts can act through Fz receptors.

  5. Ototoxicidade e otoproteção em orelha interna de cobaias utilizando gentamicina e amicacina: aspectos ultra-estruturais e funcionais Ototoxicity and otoprotection in the inner ear of guinea pigs using gentamicin and amikacin: ultrastructural and functional aspects

    Directory of Open Access Journals (Sweden)

    Thomaz José Marra de Aquino

    2008-12-01

    Full Text Available A ototoxicidade ainda é um desafio para medicina. A descoberta dos mecanismos endógenos autoprotetores das células ciliadas externas associados a métodos de avaliação funcional e ultra-estrutural das mesmas abriu nova perspectiva no entendimento e controle destes mecanismos. OBJETIVO: O trabalho objetivou determinar se subdoses de gentamicina protegia contra ototoxicidade da amicacina baseado nestes mecanismos e determinar se a amplitude das emissões otoacústicas teria correlação com grau de integridade das células ciliadas. MATERIAL E MÉTODO: Estudo experimental. Utilizando 31 cobaias, administrou-se soro fisiológico, gentamicina e amicacina, isoladamente e associadas, via intramuscular, por 12, 30 e 42 dias. Pesquisa de emissões otoacústicas foi realizada no início e final do experimento, comparado com estudo da integridade coclear, por microscopia eletrônica. RESULTADOS: Subdoses de gentamicina não protegeram a orelha interna contra toxicidade da amicacina; diminuições da amplitude das emissões otoacústicas apresentaram forte correlação com aumento de lesões das células ciliadas. CONCLUSÃO: Os achados contribuem para o entendimento dos mecanismos de ototoxicidade e otoproteção da orelha interna. A determinação da correlação entre amplitude de emissões e integridade celular tem grande importância no acompanhamento das lesões de células ciliadas, com possível aplicação no monitoramento de ototoxicidade por drogas em humanos.Ototoxicity is still a challenge to medicine. The discovery of self-protecting endogenous mechanisms of the outer hair cells associated with their functional and ultra-structural assessment methods has opened new horizons in the understanding and controlling of these mechanisms. AIM: this paper aimed at establishing whether or not underdoses of gentamicin could protect the inner ear against the harmful effects of amikacin, based on these protection mechanisms and determine if the

  6. A questionnaires study on cochlear implantation in patients with malformed inner ear%内耳畸形人工耳蜗植入术后听力言语康复效果分析

    Institute of Scientific and Technical Information of China (English)

    李旭; 陈阳; 王方圆; 温立婷; 高雪; 邱建华

    2009-01-01

    目的:使用听觉和言语问卷分级及术后产生听觉的最小电流值(T值)的方法,评估并比较内耳畸形与正常解剖结构语前聋患儿人工耳蜗植入术后的听觉言语康复效果.方法:按术前影像学检查将语前聋人工耳蜗植入患儿分为正常结构组和内耳畸形组,并配对组合,对患儿家长进行问卷形式调查随访,对术后听力及言语康复效果进行评估分析,记录术后1年调机T值.用秩和检验比较2组听觉行为分级标准(CAP)、言语可懂度分级标准(SIR)结果及T值.结果:人工耳蜗植入患儿家长术前主要担心术后效果不理想及手术并发症的发生,多数认为听力言语康复训练应由医疗机构进行;秩和检验显示:2组CAP及SIR均无显著差异,术后1年调机时产生听觉的T值无显著差异.结论:①内耳畸形患儿人工耳蜗植入术后,经正规康复训练,听力言语康复效果与内耳解剖结构正常植入者相同,人工耳蜗植入术可帮助伴耳蜗畸形的极重度感音神经性聋患者重建听力,重返主流社会;②听力言语康复训练尚有很多方面需要改进.%Objective: To investigate the clinical experiences and access the auditory performance and speech intelligibility of cochlear implantees with inner ear malformations. Method: A retrospective study was performed on the surgical characteristics and the mapping characteristics after implantation of patients who received mult-channel cochlear implantation from 2000 to 2007 in Xijing Hospital. Matched with normal implantee, rank -sum test was performed to compare scores of categories of auditory performance(CAP)and speech intelligibility rating(SIR). Result: After the regular rehabilitation, the long term follow-up of the auditory performance and speech intelligibility were very positive. There was no significant difference between normal group and malformations group. Conclusion: The cochear implantation can be performed safely in patients

  7. External Otitis (Swimmer's Ear)

    Science.gov (United States)

    ... to Pneumococcal Vaccine Additional Content Medical News External Otitis (Swimmer's Ear) By Bradley W. Kesser, MD, Associate ... the Outer Ear Ear Blockages Ear Tumors External Otitis (Swimmer's Ear) Malignant External Otitis Perichondritis External otitis ...

  8. Ear Infections in Children

    Science.gov (United States)

    ... Home » Health Info » Hearing, Ear Infections, and Deafness Ear Infections in Children On this page: What is ... additional information about ear infections? What is an ear infection? An ear infection is an inflammation of ...

  9. Evolution: Fossil Ears and Underwater Sonar.

    Science.gov (United States)

    Lambert, Olivier

    2016-08-22

    A key innovation in the history of whales was the evolution of a sonar system together with high-frequency hearing. Fossils of an archaic toothed whale's inner ear bones provide clues for a stepwise emergence of underwater echolocation ability.

  10. Airplane Ear

    Science.gov (United States)

    ... severe hearing loss Ringing in your ear (tinnitus) Spinning sensation (vertigo) Vomiting resulting from vertigo Bleeding from ... the back of the nasal cavity and the top of the throat meet (nasopharynx). When an airplane ...

  11. Analysis of the main components of inner ear antigens inducing autoimmune Meniere's disease in guinea pigs%豚鼠自身免疫性梅尼埃病模型的主要内耳抗原分析

    Institute of Scientific and Technical Information of China (English)

    陆玲; 谭长强; 崔毓桂; 丁贵鹏; 居晓斌; 李玉瑾; 蔡文君

    2008-01-01

    目的 探寻导致豚鼠自身免疫性梅尼埃病(autoimmune Meniere's disease,AIMD)的主要内耳组织抗原成分.方法 采用同种粗制内耳抗原免疫豚鼠,观察听觉功能、前庭功能及内耳组织形态学方面的变化,判断AIMD模型与非模型动物.采用免疫印迹法(Western blotting)对比分析模型动物与非模型动物血清内针对内耳组织抗原不同成分特异性免疫反应的差异,寻找只针对AIMD模型动物的特异性成分.结果 内耳组织所含抗原成分较多,免疫后酶联免疫吸附试验(ELISA)结果显示,AIMD模型与非AIMD模型动物均不同程度地存在针对内耳组织抗原的血清抗体水平升高.听功能检测,非AIMD模型动物听力损失不明显.Western bohting结果显示,AIMD模型动物出现针对相对分子质量为68 000、58 000、42 000及28 000蛋白质成分的反应条带,而非AIMD模型动物则未显示这些条带的特异性抗原抗体反应.结论 可能只有出现针对导致内耳自身免疫性疾病的主要抗原成分的特异性免疫反应,才会造成明显的内耳免疫病理损伤和功能障碍.相对分子质量为68 000、58 000、42 000及28 000的内耳组织抗原可能是导致豚鼠自身免疫性膜迷路积水的主要抗原成分.%Objective To investigate the main components of inner ear antigens inducing autoimmune Meniere's disease(AIMD) in guinea pigs. Methods The guinea pigs were immunized with isologous crude inner ear antigens (ICIEAg). Then, the hearing function was measured with auditory brainstem response (ABR), the vestibular function was measured with electronystagmography (including spontaneous nystagmus and caloric test), and inner ear histopatholoical changes were observed by inner eareelloidin section with haematoxylin-eosin staining and observed under light microscope. According to these results, the AIMD-model animals from non-AIMD-model ones were distinguished. The special antibodies against ICIEAg in sera were

  12. Development and Integration of the Ear.

    Science.gov (United States)

    Fuchs, Jennifer C; Tucker, Abigail S

    2015-01-01

    The perception of our environment via sensory organs plays a crucial role in survival and evolution. Hearing, one of our most developed senses, depends on the proper function of the auditory system and plays a key role in social communication, integration, and learning ability. The ear is a composite structure, comprised of the external, middle, and inner ear. During development, the ear is formed from the integration of a number of tissues of different embryonic origin, which initiate in distinct areas of the embryo at different time points. Functional connections between the components of the hearing apparatus have to be established and maintained during development and adulthood to allow proper sound submission from the outer to the middle and inner ear. This highly organized and intimate connectivity depends on intricate spatiotemporal signaling between the various tissues that give rise to the structures of the ear. Any alterations in this chain of events can lead to the loss of integration, which can subsequently lead to conductive hearing loss, in case of outer and middle ear defects or sensorineural hearing loss, if inner ear structures are defective. This chapter aims to review the current knowledge concerning the development of the three ear compartments as well as mechanisms and signaling pathways that have been implicated in the coordination and integration process of the ear.

  13. Mechanics of the frog ear

    NARCIS (Netherlands)

    Van Dijk, Pim; Mason, Matthew J.; Schoffelen, Richard L. M.; Narins, Peter M.; Meenderink, Sebastiaan W. F.

    2011-01-01

    The frog inner ear contains three regions that are sensitive to airborne sound and which are functionally distinct. (1) The responses of nerve fibres innervating the low-frequency, rostral part of the amphibian papilla (AP) are complex. Electrical tuning of hair cells presumably contributes to the f

  14. Pressure difference receiving ears

    DEFF Research Database (Denmark)

    Michelsen, Axel; Larsen, Ole Næsbye

    2007-01-01

    of such pressure difference receiving ears have been hampered by lack of suitable experimental methods. In this review, we review the methods for collecting reliable data on the binaural directional cues at the eardrums, on how the eardrum vibrations depend on the direction of sound incidence, and on how sound...... waves behave in the air spaces leading to the interior surfaces of eardrums. A linear mathematical model with well-defined inputs is used for exploring how the directionality varies with the binaural directional cues and the amplitude and phase gain of the sound pathway to the inner surface...

  15. In situ elemental analysis and visualization in cryofixed nervous tissues. X-ray microanalytical investigations of embryological and mature brain, inner ear, photoreceptors, muscle and muscle spindles. Comparison of preparation methods for analysis and visualization at cellular and subcellular levels.

    Science.gov (United States)

    Wróblewski, R

    1989-07-01

    visualization of the specimens prepared by cryomethods. Charging, low contrast, mass loss and contamination, which are often negligible in conventional electron microscopy, have still to be solved in XRMA of cryoprepared specimens. However, the methods of semi-thin and thick cryosectioning and low-temperature embedding were successfully used for analysis of cells and organelles and for the study of fluids in restricted biological spaces such as the inner ear, muscle spindles and ventricles of the brain in rats. Accordingly, examinations which were impossible by micropuncture and ion selective techniques could be carried out by XRMA.(ABSTRACT TRUNCATED AT 400 WORDS)

  16. The Value of 64-slice Spiral CT with 3D Transparency Reconstruction in the Diagnosis of Inner ear Malformation:Analysis of 32 Cases%64排CT三维透明化重组在内耳畸形诊断中的应用

    Institute of Scientific and Technical Information of China (English)

    王丹; 曹绍东; 申宝忠; 张同; 白荣杰; 王可铮; 徐艳

    2011-01-01

    目的 探讨三维透明化重组在内耳畸形诊断中的应用价值,为先天性内耳疾病提供准确的影像诊断和临床治疗信息.资料与方法 回顾32耳内耳畸形的64排高分辨率CT(HRCT)容积数据,行三维透明化重组处理,按内耳畸形分类总结三维透明化重组方法及影像表现.结果 32耳的三维透明化容积再现(VR)图像结合透明化多平面重组(MPR)图像均能很好揭示内耳畸形病变部位及程度,内耳病变整体显示方面及蜗窗、前庭窗、半规管等细节病变显示中透明化VR像及透明化MPR像明显优于轴位像及普通MPR像;在耳蜗内部结构的显示中,透明化MPR、轴位像及普通MPR像优于透明化VR像.32耳先天内耳发育畸形有以下几种:耳蜗未发育(2耳);共同腔畸形(4耳);不完全分隔Ⅰ型(2耳,2例患者对侧耳均为共同腔畸形);不完全分隔Ⅱ型(即Mondini型)(16耳,多合并前庭、半规管及前庭导水管畸形);单纯前庭-半规管畸形(2耳);单纯前庭导水管扩大(6耳).结论 三维透明化个性重组能准确}半价内耳先天性疾病的类型和程度,为临床治疗提供重要的参考依据.%Objective To investigate the role of 3D transparency reconstruction in displaying the inner ear malformation. Materials and Methods Thirty-two cases of inner ear malformation were analyzed retrospectively. The data of 64 slice HRCT were processed using 3D transparency reconstruction. The imaging findings were summarized according to the categorization of the disease. Results The malformations included cochlear aplasia(2 ears), Common cavity deformity (4 ears), incomplete partition Ⅰ (2 ears ), incomplete partition Ⅱ ( Mondini deformity ) ( 16 ears), vestibular and semicircular canal malformations(3 ears) and vestibular aqueduct dilate(6 ears). The site and degree of inner ear malformation were displayed clearly by 3D transparent reconstruction imaging and MPR transparent imaging. Transparent MPR and VR

  17. Travel Inside the Ear

    Medline Plus

    Full Text Available ... Info » Hearing, Ear Infections, and Deafness Travel Inside the Ear Video When sound waves reach your ear, ... heard a soft sound or a loud sound. The sound passes through the outer ear and is ...

  18. Ear Plastic Surgery

    Science.gov (United States)

    ... ENTCareers Marketplace Find an ENT Doctor Near You Ear Plastic Surgery Ear Plastic Surgery Patient Health Information ... they may improve appearance and self-confidence. Can Ear Deformities Be Corrected? Formation of the ear during ...

  19. Better Ear Health

    Science.gov (United States)

    ... Marketplace Find an ENT Doctor Near You Better Ear Health Better Ear Health Patient Health Information News ... often helpful to those with this condition. Swimmer’s Ear An infection of the outer ear structures caused ...

  20. How the Ear Works

    Science.gov (United States)

    ... Find an ENT Doctor Near You How the Ear Works How the Ear Works Patient Health Information News media interested in ... public relations staff at newsroom@entnet.org . The ear has three main parts: the outer ear (including ...

  1. Cosmetic ear surgery

    Science.gov (United States)

    Otoplasty; Ear pinning; Ear surgery - cosmetic; Ear reshaping; Pinnaplasty ... Cosmetic ear surgery may be done in the surgeon's office, an outpatient clinic, or a hospital. It can be performed under ...

  2. 多层螺旋 CT 多平面重组在诊断先天感音神经性耳聋儿童内耳畸形中的应用%The diagnostic value of multiplanar reconstruction of multi-slice spiral CT in pediatric sensorineural hearing loss children induced by inner ear malformation

    Institute of Scientific and Technical Information of China (English)

    胡辉军; 李国照; 王东烨; 张翔; 沈君

    2015-01-01

    Objective To investigate the diagnostic value of multiplanar reconstruction (MPR) of multi-slice spiral CT (MSCT) in inner ear malformation of children. Methods Retrospective analysis of 223 children in Sun Yat-Sen Memorial Hospital suspected sensorineural hearing loss (SNHL) clinically was performed between September 2010 and March 2014. All the patients received MSCT scan and 68 patients of inner ear malformation were detected. Deformed bony labyrinths of 68 patients and two cases of normal inner ear were reconstructed with the method of MPR on basis of raw data of MSCT images by one radiologist. In 68 patients of inner ear malformation, there were 33 males and 35 females (aged from 9 days to 16 years). Two senior radiologists evaluated the MSCT manifestations of 68 patients and than statistics analysis of classification for inner ear malformation were performed. Results Sixty-eight patients (5 patients with single ear malformation, 63 patients with bilateral ear malformation, 131 ears in total) with SNHL were clearly shown by MPR images. There were 33 ears of cochlear malformation, 39 ears of vestibular malformation, 42 ears of semicircular canal malformation, 18 ears of internal auditory canal malformation and 86 ears of vestibular aqueduct malformation. In 68 patients (131 ears), single constructive malformation was detected in 8 ears (6. 1% ), two or more kinds of combined malformations were detected in 123 ears (93. 9% ). Conclusions Most of these patients suffered from two or more kinds of combined malformations. MPR images can display the structures of cochlear, vestibule, semicircular canal, internal auditory canal and vestibular aqueduct. The application of this kind of post-processing technology is expected to improve the detection rate of inner ear malformation, especially the various structural malformations, which is conducive to the treatment decisions making and surgical planning.%目的:探讨多层螺旋 CT(MSCT)多平面重组(MPR)技术在

  3. Cochlear implant in patients with congenital malformation of the inner ear%先天性内耳畸形患者人工耳蜗植入的临床体会

    Institute of Scientific and Technical Information of China (English)

    万良财; 郭梦和; 钱宇虹; 刘双秀; 张宏征; 陈帅君; 陈浩; 龚剑

    2009-01-01

    Objective To summarize the clinical experience with multi-channel cochlear implantation in patients with inner ear malformations and evaluate and the outcomes of speech rehabilitation. Methods A retrospective study was conducted in 295 patients receiving cochlear implantation from 1998 to 2007, including 25 patients with large vestibular aqueduct syndrome (LVAS), 9 with Modini malformation, and 5 with common cavity deformity. All the patients received the Nucleus24 cochlear implants. In LVAS cases, 4 had Nucleus 24R (ST) implants, 8 had Contuor implants, 10 had Contuor Advance, and the remaining cases used Nucleus24(M) straight-electrode implants. Results Severe gusher appeared in 3 cases of LVAS, and perilymph fluctuation were seen in aother 15 cases. Four patients with Mondini malformation and 2 with common cavity malformation also experienced severe gusher, but the electrodes were inserted smoothly in all the patients without postoperative facial paralysis or cerebrospinal fluid leakage. The hearing threshold in these patients was similar to that in patients with normal cochlear structure. After speech rehabilitation for over 6 months, the abilities of speech discrimination and spoken language improved in all the cases in comparison with the preoperative lingual functions. Conclusion Multi-channel cochlear implantation can be performed in patients with inner ear malformation, but should not be attempted in patients with poor cochlear and cochlear nerve development. A comprehensive pre-operative radiographic and audiological evaluation is essential.%目的 探讨先天性内耳畸形重度或极重度感音神经性聋患者人工耳蜗植入方法及术后言语康复效果.方法 回顾性分析1998-2007年于我科行人工耳蜗植入295例患者的临床资料,其中前庭水管扩大25例,Modini畸形9例,共同腔畸形5例.所有患者均采用澳大利亚Nucleus24型人工耳蜗.对大前庭水管综合症患者,4例采用Nucleus 24R(ST)型植入体.8

  4. The expression pattern and inhibitory influence of Tenascin-C on the growth of spiral ganglion neurons suggest a regulatory role as boundary formation molecule in the postnatal mouse inner ear.

    Science.gov (United States)

    Kwiatkowska, M; Reinhard, J; Roll, L; Kraft, N; Dazert, S; Faissner, A; Volkenstein, S

    2016-04-05

    Sensorineural hearing loss, as a consequence of acoustic trauma, aging, genetic defects or ototoxic drugs, is highly associated with irreversible damage of cochlear hair cells (HCs) and secondary degeneration of spiral ganglion (SG) cells. Cochlear implants (CIs), which bypass the lost HC function by direct electrical stimulation of the remaining auditory neurons, offer an effective therapy option. Several studies imply that components of the extracellular matrix (ECM) have a great impact on the adhesion and growth of spiral ganglion neurons (SGNs) during development. Based on these findings, ECM proteins might act as bioactive CI substrates to optimize the electrode-nerve interface and to improve efficacy of these implants. In the present study, we focused on the ECM glycoproteins Tenascin-C (TN-C), Laminin (LN), and Fibronectin (FN), which show a prominent expression along the growth route of SGNs and the niche around HCs during murine postnatal development in vivo. We compared their influence on adhesion, neurite length, and neurite number of SGNs in vitro. Moreover, we studied the expression of the chondroitin sulfate proteoglycan (CSPG) dermatan sulfate-dependent proteoglycan-1 (DSD-1-PG), an interaction partner of TN-C. In sum, our in vitro data suggest that TN-C acts as an anti-adhesive and inhibitory factor for the growth of SGNs. The DSD-1 carbohydrate epitope is specifically localized to HC stereocilia and SG fibers. Interestingly, TN-C and the DSD-1-PG exhibit a mutually exclusive expression pattern, with the exception of a very restricted region beneath the habenula perforata, where SG neurites grow through the basilar membrane (BM) toward the HCs. The complementary expression of TN-C, LN, FN, and the DSD-1 epitope suggests that TN-C may act as an important boundary formation molecule in the developing postnatal mouse inner ear, which makes it a promising candidate to regulate neurite outgrowth in the light of CIs.

  5. A Model for the representation of Speech Signals in Normal and Impaired Ears

    DEFF Research Database (Denmark)

    Christiansen, Thomas Ulrich

    2004-01-01

    A model of human auditory periphery, ranging from the outer ear to the auditory nerve, was developed. The model consists of the following components: outer ear transfer function, middle ear transfer function, basilar membrane velocity, inner hair cell receptor potential, inner hair cell probabili...

  6. 感音神经性聋患儿中先天性内耳畸形的构成、影像学及临床听力学特征%Constitute, imaging and auditory characteristics of pediatric patients with congenital malformations of inner ear in sensorineural hearing loss

    Institute of Scientific and Technical Information of China (English)

    李幼瑾; 杨军; 李蕴

    2011-01-01

    目的:分析婴幼儿、儿童先天性感音神经性聋(SNHL)中先天性内耳畸形的构成、影像学及临床听力学特征.方法:回顾性分析2005-02-2010-01上海交通大学医学院附属上海儿童医学中心耳鼻咽喉科诊治的860例先天性SNHL患儿中,经颞骨高分辨率CT及MRI发现有先天性内耳畸形的125例(225耳)患儿的听力学及影像学资料.结果:860例先天性SNHL患儿中有先天性内耳畸形者占14.5%;累及双侧98例(78.4%),单侧27例(21.6%).225耳中167耳(74.2%)为极重度聋,36耳(16%)为重度聋,22耳(9.8%)为中度聋.该组内耳畸形中,前庭水管扩大最多见(75.6%),其次为前庭畸形(32%),再次为耳蜗前庭畸形(23.1%).耳蜗前庭畸形中以Mondini畸形最常见(55.8%),其次为共同腔畸形(28.9%).累及耳蜗的内耳畸形中极重度聋者明显多于未累及耳蜗的内耳畸形中极重度聋者.结论:对了解中国婴幼儿、儿童先天性SNHL中先天性内耳畸形的构成,对先天性SNHL的病因诊断以及对包括助听器、耳蜗植入等在内的干预策略的制订及其预后有一定意义.%Objective:To analyze the constitute, imaging and auditory characteristics of pediatric patients with congenital malformations of inner ear in sensorineural hearing loss(SNHL). Method.. Imaging and auditory data of 125 cases(225 ears) in 860 pediatric patients with congenital SNHL who referred to ENT department of Shanghai Children Medical Center from February 2005 to January 2010 were retrospectively studied. Result:Congenital malformations of inner ear accounted for 14.5 % in 860 pediatric patients with congenital SNHL. Bilateral ear was involved in 98 cases(78. 4%), unilateral in 27cases(21.6%). One hundred and sixty-seven ears (74. 2%) were identified as profound deafness, 36 ears (16%) severe deafness and 22 ears (9.8%) moderate deafness in 225 ears,respectively. In present group, large vestibular aqueduct (75.6 %) was the most common and next

  7. Development and regeneration of the inner ear.

    Science.gov (United States)

    Kwan, Tao; White, Patricia M; Segil, Neil

    2009-07-01

    Loss of sensory hair cells is the leading cause of deafness in humans. The mammalian cochlea cannot regenerate its complement of sensory hair cells. Thus at present, the only treatment for deafness due to sensory hair cell loss is the use of prosthetics, such as hearing aids and cochlear implants. In contrast, in nonmammalian vertebrates, such as birds, hair cell regeneration occurs following the death of hair cells and leads to the restoration of hearing. Regeneration in birds is successful because supporting cells that surround the hair cells can divide and are able to subsequently differentiate into new hair cells. However, supporting cells in mammals do not normally divide or transdifferentiate when hair cells are lost, and so regeneration does not occur. To understand the failure of mammalian cochlear hair cell regeneration, we need to understand the molecular mechanisms that underlie cell division control and hair cell differentiation, both during embryogenesis and in the postnatal mouse. In this review, we present a discussion of the regulation of cell proliferation in embryogenesis and during postnatal maturation. We also discuss the role of the Cip/Kip cell cycle inhibitors and Notch signaling in the control of stability of the differentiated state of early postnatal supporting cells. Finally, recent data indicate that some early postnatal mammalian supporting cells retain a latent capacity to divide and transdifferentiate into sensory hair cells. Together, these observations make supporting cells important therapeutic targets for continued efforts to induce hair cell regeneration.

  8. Chicken (Gallus domesticus) inner ear afferents

    Science.gov (United States)

    Hara, H.; Chen, X.; Hartsfield, J. F.; Hara, J.; Martin, D.; Fermin, C. D.

    1998-01-01

    Neurons from the vestibular (VG) and the statoacoustic (SAG) ganglion of the chick (Gallus domesticus) were evaluated histologically and morphometrically. Embryos at stages 34 (E8 days), 39 (E13 days) and 44 (E18 days) were sacrificed and temporal bones microdissected. Specimens were embedded in JB-4 methacrylate plastic, and stained with a mixture of 0.2% toluidine blue (TB) and 0.1% basic Fuschin in 25% ethanol or with a mixture of 2% TB and 1% paraphenylenediamine (PDA) for axon and myelin measurement study. Images of the VIIIth nerve were produced by a V150 (R) color imaging system and the contour of 200-300 neuronal bodies (perikarya) was traced directly on a video screen with a mouse in real time. The cross-sectional area of VG perikarya was 67.29 micrometers2 at stage 34 (E8), 128.46 micrometers2 at stage 39 (E13) and 275.85 micrometers2 at stage 44 (E18). The cross-sectional area of SAG perikarya was 62.44 micrometers2 at stage 34 (E8), 102.05 micrometers2 at stage 39 (E13) and 165.02 micrometers2 at stage 44 (E18). A significant cross-sectional area increase of the VG perikarya between stage 39 (E13) and stage 44 (E18) was determined. We randomly measured the cross-sectional area of myelin and axoplasm of hatchling afferent nerves, and found a correspondence between axoplasmic and myelin cross-sectional area in the utricular, saccular and semicircular canal nerve branches of the nerve. The results suggest that the period between stage 34 (E8) and 39 (E13) is a critical period for afferent neuronal development. Physiological and behavioral vestibular properties of developing and maturing hatchlings may change accordingly. The results compliment previous work by other investigators and provide valuable anatomical measures useful to correlate physiological data obtained from stimulation of the whole nerve or its parts.

  9. Drug delivery to the inner ear

    Science.gov (United States)

    Wise, Andrew K.; Gillespie, Lisa N.

    2012-12-01

    Bionic devices electrically activate neural populations to partially restore lost function. Of fundamental importance is the functional integrity of the targeted neurons. However, in many conditions the ongoing pathology can lead to continued neural degeneration and death that may compromise the effectiveness of the device and limit future strategies to improve performance. The use of drugs that can prevent nerve cell degeneration and promote their regeneration may improve clinical outcomes. In this paper we focus on strategies of delivering neuroprotective drugs to the auditory system in a way that is safe and clinically relevant for use in combination with a cochlear implant. The aim of this approach is to prevent neural degeneration and promote nerve regrowth in order to improve outcomes for cochlear implant recipients using techniques that can be translated to the clinic.

  10. Benign ear cyst or tumor

    Science.gov (United States)

    Osteomas; Exostoses; Tumor - ear; Cysts - ear; Ear cysts; Ear tumors; Bony tumor of the ear canal ... bony tumors of the ear canal (exostoses and osteomas) are caused by excess growth of bone. Repeated ...

  11. Mouse middle ear ion homeostasis channels and intercellular junctions.

    Directory of Open Access Journals (Sweden)

    Lisa M Morris

    Full Text Available HYPOTHESIS: The middle ear contains homeostatic mechanisms that control the movement of ions and fluids similar to those present in the inner ear, and are altered during inflammation. BACKGROUND: The normal middle ear cavity is fluid-free and air-filled to allow for effective sound transmission. Within the inner ear, the regulation of fluid and ion movement is essential for normal auditory and vestibular function. The same ion and fluid channels active in the inner ear may have similar roles with fluid regulation in the middle ear. METHODS: Middle and inner ears from BALB/c mice were processed for immunohistochemistry of 10 specific ion homeostasis factors to determine if similar transport and barrier mechanisms are present in the tympanic cavity. Examination also was made of BALB/c mice middle ears after transtympanic injection with heat-killed Haemophilus influenza to determine if these channels are impacted by inflammation. RESULTS: The most prominent ion channels in the middle ear included aquaporins 1, 4 and 5, claudin 3, ENaC and Na(+,K(+-ATPase. Moderate staining was found for GJB2, KCNJ10 and KCNQ1. The inflamed middle ear epithelium showed increased staining due to expected cellular hypertrophy. Localization of ion channels was preserved within the inflamed middle ear epithelium. CONCLUSIONS: The middle ear epithelium is a dynamic environment with intrinsic mechanisms for the control of ion and water transport to keep the middle ear clear of fluids. Compromise of these processes during middle ear disease may underlie the accumulation of effusions and suggests they may be a therapeutic target for effusion control.

  12. 内耳畸形小儿人工耳蜗植入术后电极阻抗测试的研究%An study of electrode impedance characteristics with cochlear implants in children with malformed inner ear

    Institute of Scientific and Technical Information of China (English)

    乔晓峰; 王东

    2013-01-01

    Objective To investigate the changes of electrode impedance with cochlear implants in children with malformed inner ear. Methods 36 children with multi-channel cochlear implants participated in this study, to test the electrode impedance values. Results Electrode impedance was not significantly different at different locations. Electrode impedance was at its lowest level during the operation and reached the highest level at the first stimulation which was 1 month after the operation. The impedance turned to a gradual decrease, and stabilized 3 months after the operation. Conclusion The values varied in different programming sessions and electrodes during the first 3 months of cochlear implant use. To acquire better hearing frequent programming sessions are necessary.%目的探讨内耳畸形小儿人工耳蜗植入手术后,植入体电极阻抗值的变化特点及规律。方法对36例澳大利亚Cochlear Nucleus 24型内耳畸形小儿人工耳蜗植入手术患儿,测试手术中及手术后1年阻抗值,并分析其特点及变化规律。结果患儿术中及开机后1年内高中低频段电极阻抗值变化趋势相同。电极阻抗值术中自开机显著增大,术中阻抗值最低,开机达到最大值,其后呈下降趋势,于开机3月后趋于平稳。结论内耳畸形小儿人工耳蜗植入手术后电极阻抗值开机3个月内变化明显,故需多次调机,以使患者语言感知达到最佳状态。

  13. Ear Disorders in Scuba Divers

    Directory of Open Access Journals (Sweden)

    MH Azizi

    2010-12-01

    Full Text Available History of underwater diving dates back to antiquity. Breath-hold technique in diving was known to the ancient nations. However, deep diving progressed only in the early decades of the 19th century as the result of advancements in efficient underwater technologies which subsequently led to invention of sophisticated sets of scuba diving in the 20th century. Currently, diving is performed for various purposes including commercial, recreational, military, underwater construction, oil industry, underwater archeology and scientific assessment of marine life. By increasing popularity of underwater diving, dive-related medical conditions gradually became more evident and created a new challenge for the health care professionals, so that eventually, a specialty the so-called “diving medicine” was established. Most of the diving-associated disorders appear in the head and neck. The most common of all occupational disorders associated with diving are otologic diseases. External otitis has been reported as the most common otolaryngologic problem in underwater divers. Exostosis of the external ear canal may be formed in divers as the result of prolonged diving in cold waters. Other disorders of the ear and paranasal sinuses in underwater divers are caused by barometric pressure change (i.e., barotraumas, and to a lesser extent by decompression sickness. Barotrauma of the middle ear is the most prevalent barotrauma in divers. The inner ear barotraumas, though important, is less common. The present paper is a brief overview of diving-related ear disorders particularly in scuba divers.

  14. Ear infection - chronic

    Science.gov (United States)

    Middle ear infection - chronic; Otitis media - chronic; Chronic otitis media; Chronic ear infection ... up. When this happens, infection can occur. A chronic ear infection develops when fluid or an infection ...

  15. Ear tube insertion - slideshow

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/presentations/100045.htm Ear tube insertion - series—Normal anatomy To use the ... 4 Overview The eardrum (tympanic membrane) separates the ear canal from the middle ear. Review Date 8/ ...

  16. Numerical analysis of ossicular chain lesion of human ear

    Institute of Scientific and Technical Information of China (English)

    Yingxi Liu; Sheng Li; Xiuzhen Sun

    2009-01-01

    Lesion of ossicular chain is a common ear disease impairing the sense of hearing. A comprehensive numerical model of human ear can provide better understanding of sound transmission. In this study, we propose a three-dimensional finite element model of human ear that incorporates the canal, tympanic membrane, ossicular bones,middle ear suspensory ligaments/muscles, middle ear cavity and inner ear fluid. Numerical analysis is conducted and employed to predict the effects of middle ear cavity, malleus handle defect, hypoplasia of the long process of incus,and stapedial crus defect on sound transmission. The present finite element model is shown to be reasonable in predicting the ossicular mechanics of human ear.

  17. 突发聋和梅尼埃病鼓室灌注疗效与内耳MRI显影相关性%Relationship of trans-tympanic administration effect with inner ear MRI visualization in patients with Meniere's disease and idiopathic sudden hearing loss

    Institute of Scientific and Technical Information of China (English)

    吴佳欐; 陈文文; 罗禹; 童军; 邓亚新; 单良; 方旭华

    2011-01-01

    目的 研究突发聋和梅尼埃病鼓室灌注疗效与内耳MRI显影的相关性.方法 17例患者(突发聋13例,梅尼埃病4例)给予鼓室插管并注射钆造影剂,术后1 h、1 d、6d行MRI连续扫描,1周后复查电测听,评估眩晕改善情况,分析钆剂是否透入内耳和症状改善的相关性.结果 17例中9例(突发聋5例,梅尼埃病4例)在插管注入钆剂后1 h到6 d的MRI检查中出现内耳高信号.另8例MRI未显影者听力没有进步.结论 鼓室灌注造影剂能透入内耳者药物也能透入,治疗效果亦较好.%Objective To explore and analyze the relationship of transtympanic administration effect with inner ear MRI visualization in patients with Meniere's disease and idiopathic sudden hearing loss. Methods 17 cases (13 cases of idi-opathic sudden hearing loss and 4 cases of Meniere's disease) were enrolled in the study, Gadolium, dexamethason or gentimycin were trans-tympanically injected, and all patients were scanned with MRI 1 h, Id, and 6 d after operation. The relationship of the effect with MRI visualization was observed and analyzed. Results 9 cases (5 cases of idiopathic sudden hearing loss and 4 cases of Meniere's disease) of the 17 had inner ear high signal lh to 6d after gadolium was injected. The other 8 cases had neither signal in the inner ear nor improved hearing. Conclusion If transtympanically injected gadolium can permeate into the inner ear, dexamethoson and gentimycin would also permeate into it, and the therapy would have a good effect.

  18. Determination of the volumes of inner ear and internal auditory canal fluid in thirty normal adults using magnetic resonance hydrography%正常成人内耳系统液体容积的磁共振测量与分析

    Institute of Scientific and Technical Information of China (English)

    沈安民; 史波宁; 许军; 王海涛; 王良炯

    2011-01-01

    Objective To evaluate the value of magnetic resonance hydrography in the determination of the volumes of inner ear and internal auditory canal fluid.Methods Three-dimensional fast imaging employing steady state acquisition magnetic resonance images of thirty normal adults( sixty ears)were performed by using GE1.5T and eightchannel head coil, then sent to AW4.2 workstation to establish optimal observation plane using muhiplanar reconstruction (MPR) and three-dimensional volume reconstruction, to measure the volumes of inner ear and internal auditory canal and establish a preliminary range of normal value.Meanwhile the volumes of inner ear and internal auditory canal with regard to gender, ear-side and age were analyzed respectively.Results The volumes and range of normal value of cochlea,semicircular canal-vestibule and internal auditory canal in thirty normal adults were ( 101.2 ± 11.1 ) mm3 and (79.4-123.0) mm3, ( 151.5 ± 19.9) mm3 and ( 112.5-190.5 ) mm3, ( 220.1 ± 58.7 ) mm3 and (105.0-335.2) mm3, respectively.The coefficients of variation were 0.11,0.13 and 0.27, respectively.There was no significant difference among the volumes of inner ear and internal auditory canal with regard to gender, ear-side and age (P > 0.05 ).Conclusion Magnetic resonance hydrography may serve as a preferable objective measure for assessing the volumes of inner ear and internal auditory canal in vivo and provide the anatomical foundation for evaluation of inner ear system and classification of inner ear malformation.%目的 探讨磁共振三维水成像技术在内耳液体容积测量中的应用价值.方法 30例正常成人志愿者均采用GE1.5T磁共振机、8通道头部相控阵线圈,行内耳内听道水成像序列扫描(三维真稳态进动快速成像序列),所采集信号传送至工作站AW4.2进行多平面重建和容积重建,测量耳蜗、前庭-半规管和内听道容积,初步建立其正常值范围,并分别比较耳别、性别及

  19. Play it by Ear

    DEFF Research Database (Denmark)

    Kammersgaard, Nikolaj Peter Iversen; Kvist, Søren Helstrup; Thaysen, Jesper

    2014-01-01

    The first antenna for ear-to-ear communication with a standard Bluetooth chip has the potential to improve hearing aid technology.......The first antenna for ear-to-ear communication with a standard Bluetooth chip has the potential to improve hearing aid technology....

  20. Adenovirus-Mediated IL-10 Gene for the Treatment of Autoimmune Inner Ear Disease-an Experimental Study%腺病毒介导的白细胞介素-10治疗自身免疫性内耳病的实验研究

    Institute of Scientific and Technical Information of China (English)

    蔡文君; 谭长强

    2015-01-01

    Objective To evaluate therapeutic effects of transferring recombinant replication -defective ade‐novirus vector of interleukin 10(IL -10) gene into inner ear of guinea pig for the treatment of autoimmune inner ear disease .Methods The conspecific crude inner ear antigens (CIEAgs) were prepared and used to immunize guinea pigs with Freund's adjuvant that resulted autoimmune inner ear diseases (AIED) in 20 animals .Then they were ran‐domly divided into three groups .Through the way of round window membrane micro -injection ,adenovirus vector containing IL -10(Ad -IL -10) gene were implanted in group A(ten animals) ,recombinant adenovirus with yellow fluorescent protein(Ad -EYFP) marked was implanted in group B(five animals) ,and artificial perilymph were implanted in group C( five animals) .Seven days later ,auditory brain-stem response (ABR) thresholds were determined ,the guinea pig inner ears were obtained ,and the immunohistochemistry staining were perform for detec‐ting adenovirus vector transfection with immunofluorescence and the gene product interleukin 10 expressions with enzyme immunohistochemistry .Results Immunohistochemistry staining showed that the adenovirus carrying IL -10 gene could transfer the psalterial cord ,spiral ligament ,Corti organ ,spiral ganglion ,cochlear axis vessels and co‐chlear bone paries .It could generate gene product (IL -10 ) in same sites .The mean ABR thresholds were increased in each group after modeling .The differences were statistically significant .After injection of the inner ear ,the mean ABR thresholds of group A were lower than those of group B and group C .The light microscopic revealed the im‐munological inflammatory response were lighter than in group B and group C .Conclusion The adenovirus could transfer IL -10 gene into inner ear of guinea pig and express its products in many parts of inner ear .The immunity regulating gene can reduce the immunity damage and hearing functional impairment .%目的:研

  1. 内耳免疫反应中白细胞上α4-整合素和L-选择素的表达%Expression of α4-integrin and L-selectin on the surface of leukocytes during inner ear immune response

    Institute of Scientific and Technical Information of China (English)

    张程; 黄魏宁; 宋海涛; 高波; 周金梅

    2001-01-01

    Objective To investigate the role played by α4-integrin andL-selectin in the immune response during inner ear inflammation. Methods Labyrinthitis was induced in rats by inoculation of keyhole limpet hemocyanin(KLH) into the scalae tympani of the animals that had been systemically sensitized. Expression of L-selectin was examined with monoclonal antibodies to L-selectin with immunohistochemistry. At the same time, ELISA was used to monitor the interleukin (IL)-1 in the peripheral blood of these animals. In addition, the expression of α 4-integrin and L-selectin on the surface of leukocytes in peripheral blood were examined with flow cytometry. Results Expression of L-selectin was not found on the surface of leukocytes during the inner ear inflammation. By flow cytometry, the expression of L-selectin on the surface of leukocytes in peripheral blood showed down-regulated during inflammation. In contrast, the expression of α4-integrin on the surface of leukocytes in peripheral blood showed up-regulated during inflammation. The concentration of IL-1 in peripheral blood increased during inner ear inflammation. Conclusions The study further elucidated that the adhesion molecules played on important role on extravasation of inflammation cells from blood vessels during inner ear immune response. And, the increased expression of α4-integrin had related closely to the concentration of IL-1 in peripheral blood during inner ear inflammation.%目的 探讨α4-整合素(α4-integrin)和L-选择素(L-selectin)在内耳免疫反应中的作用。方法 采用钥孔虹 戚血蓝蛋白激发已2次全身致敏的大鼠内耳,诱发其内耳免疫反应,制造迷路炎模型,然后通过免疫组织化学技术,检测内耳L-selectin在内耳中的表达。同时用流式细胞仪检测L-selectin和α4-integrin在外周血白细胞上的表达。用ELISA法检测外周血白细胞介素1(IL-1)浓度。结果 内耳炎症期间L-selectin表达

  2. The inner voice

    Directory of Open Access Journals (Sweden)

    Anthony James Ridgway

    2009-12-01

    Full Text Available The inner voice- we all know what it is because we all have it and use it when we are thinking or reading, for example. Little work has been done on it in our field, with the notable exception of Brian Tomlinson, but presumably it must be a cognitive phenomenon which is of great importance in thinking, language learning, and reading in a foreign language. The inner voice will be discussed as a cognitive psychological phenomenon associated with short-term memory, and distinguished from the inner ear. The process of speech recoding will be examined (the process of converting written language into the inner voice and the importance of developing the inner voice, as a means of both facilitating the production of a new language and enhancing the comprehension of a text in a foreign language, will be emphasized. Finally, ways of developing the inner voice in beginning and intermediate readers of a foreign language will be explored and recommended.

  3. 内耳不完全分隔Ⅱ型畸形并自发性脑脊液耳漏的 CT、MRI 诊断价值%CT and MRI diagnostic value of the congenital inner ear malformation incomplete partition type Ⅱdeformity combined with spontaneous CSF otorrhea

    Institute of Scientific and Technical Information of China (English)

    董燕; 董季平; 杨军乐; 杨想春; 党珊; 刘润

    2015-01-01

    目的:探讨先天性内耳不完全分隔Ⅱ型畸形(Mondini 畸形)并脑脊液耳漏的高分辨 CT(HRCT)及 MRI 诊断价值。方法回顾性分析本院3例先天性内耳不完全分隔Ⅱ型畸形合并脑脊液耳漏,同时并发反复发作脑膜炎患者的影像学资料,包括HRCT 多平面重组(MPR)、曲面重组(CPR)图像及 MR 内耳水成像图像,观察病变侧内、中耳各解剖结构的形态,总结分析本病的临床及影像学特征。结果1例患者双侧发病,伴半规管发育不全,蜗水管扩大。2例患者为单侧发病,其中1例合并同侧面神经管发育不良。3例患者均有镫骨底板菲薄,内听道底缺损。结论内耳不完全分隔Ⅱ型畸形合并脑脊液耳漏,并发脑膜炎时, HRCT 及后处理、MR 检查可显示内耳、中耳精细的解剖结构,并清晰显示瘘口情况,对该病的诊断具有重要价值。%Objective To discuss the diagnostic value of high resolution computed tomography (HRCT)and MRI in the congenital inner ear malformation incomplete partition type Ⅱ deformity(Mondini deformity)combined with spontaneous cerebrospinal fluid (CSF)otorrhea.Methods The imaging data including the multiplanar reformation(MPR)images of HRCT,curved planar reforma-tion(CPR)images and MR hydrography images in three patients complicated with recurrent meningitis were retrospectively ana-lyzed.The anatomic changes of the inner ear and middle ear on the affected side were observed,the clinical and imaging features of this disease were summarized.Results One patient had bilateral incidence of the incompletely separated inner ear,combined with semicircular canal dysplasia and cochlear pipe dilation.Two patients had unilateral onset,one of them had concurrent facial nerve ca-nal dysplasia.Humble stapes floor and the defect of the bottom of the internal auditory canal were seen in all the three patients.Con-clusion HRCT with post-processing technology,and MRI have great

  4. Ear Infection and Vaccines

    Science.gov (United States)

    ... an ENT Doctor Near You Ear Infection and Vaccines Ear Infection and Vaccines Patient Health Information News ... or may need reinsertion over time. What about vaccines? A vaccine is a preparation administered to stimulate ...

  5. Middle Ear Infections

    Science.gov (United States)

    ... Listen Español Text Size Email Print Share Middle Ear Infections Page Content Article Body What are the ... illness. What if a child with a middle ear infection is in great pain and discomfort? The ...

  6. Ear surgery - slideshow

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/presentations/100016.htm Ear surgery - series—Normal anatomy To use the sharing ... Overview This image demonstrates normal appearance of the ears in relation to the face. Review Date 10/ ...

  7. Otoplasty (Cosmetic Ear Surgery)

    Science.gov (United States)

    ... By Mayo Clinic Staff Otoplasty — also known as cosmetic ear surgery — is a procedure to change the ... Society of Plastic Surgeons. http://www.plasticsurgery.org/Cosmetic-Procedures/Ear-Surgery.html. Accessed June 16, 2015. ...

  8. Middle Ear Infections (For Parents)

    Science.gov (United States)

    ... Feeding Your 1- to 2-Year-Old Middle Ear Infections KidsHealth > For Parents > Middle Ear Infections Print ... 3 years old. A Close Look at the Ear To understand how ear infections develop, let's review ...

  9. Ear Injuries (For Parents)

    Science.gov (United States)

    ... head, sports injuries, and even listening to loud music can cause ear damage, which can affect hearing and balance. That's because the ear not ... Hearing Loss or Balance Problems Ear injuries can affect kids differently. ... sounds or music notes hearing only certain or muffled sounds ringing ...

  10. Evaluation of embryological sequences of ear anomalies and its radiological relevance

    Directory of Open Access Journals (Sweden)

    C Amarnath

    2016-01-01

    Full Text Available Aim: To correlate the sequence of embryological development of ear with radiological imaging. Materials and Methods: The study enrolled 23 patients of age group 11 months to 27 years with malformed external ear/microtia and hearing loss. The children with postoperative changes, acute hearing loss (such as infection, trauma were excluded from the study. We used high-resolution computed tomography, with axial and coronal sections to examine the temporal bones of patients. Results: Of the 23 cases, 12 cases had external ear anomaly and 11 cases had cochlear anomaly. In patients with the external ear anomaly, seven cases had associated middle ear malformations, one patient had associated middle and inner ear anomaly, one had anomalous course of facial nerve, and three cases had isolated external ear anomalies. In patients with inner ear anomalies, one patient had complete labyrinthine aplasia, one had cochlear dysplasia with incomplete cochlear turns, four had common cavity malformations, one had cystic featureless cochlea with dilated and cystic vestibule, two patients had small cochlea with the middle and apical turns coalescing to form a cystic apex, one patient had small rudimentary cochlea, and the other one had dilated vestibule and enlarged endolymphatic duct and sac with cochlear dysmorphism. Conclusion: Most of the children with malformed pinna had external auditory canal atresia with associated middle ear anomalies. Though the inner ear development is independent of external and middle ear development, we insist on the fact that insult during the 1 st month of embryogenesis can result in associated abnormalities involving external, middle, and inner ear. Developmental arrest at various stages of inner ear development results in various types of cochlear anomalies with associated vestibular, semicircular canal abnormalities, and rarely associated with middle and external ear anomalies. Hence, clear knowledge about embryology will help to

  11. The ear region of Latimeria chalumnae: functional and evolutionary implications.

    Science.gov (United States)

    Bernstein, Peter

    2003-01-01

    The anatomy of Latimeria chalumnae has figured prominently in discussions about tetrapod origins. While the gross anatomy of Latimeria is well documented, relatively little is known about its otic anatomy and ontogeny. To examine the inner ear and the otoccipital part of the cranium, a serial-sectioned juvenile coelacanth was studied in detail and a three-dimensional reconstruction was made. The ear of Latimeria shows a derived condition compared to other basal sarcopterygians in having a connection between left and right labyrinths. This canalis communicans is perilymphatic in nature and originates at the transition point of the saccule and the lagena deep in the inner ear, where a peculiar sense end organ can be found. In most gnathostomes the inner ears are clearly separated from each other. A connection occurs in some fishes, e.g. within the Ostariophysi. In the sarcopterygian lineage no connections between the inner ears are known except in the Actinistia. Some fossil actinistians show a posteriorly directed duct lying between the foramen magnum and the notochordal canal, similar to the condition in the ear of Latimeria, so this derived character complex probably developed early in actinistian history. Because some features of the inner ear of Latimeria have been described as having tetrapod affinities, the problem of hearing and the anatomy of the otical complex in the living coelacanth has been closely connected to the question of early tetrapod evolution. It was assumed in the past that the structure found in Latimeria could exemplify a transitional stage in otic evolution between the fishlike sarcopterygians and the first tetrapods in a functional or even phylogenetic way. Here the possibility is considered that the canalis communicans does not possess any auditory function but rather is involved in sensing pressure changes during movements involving the intracranial joint. Earlier hypotheses of a putative tympanic ear are refuted.

  12. Impedance matching, optimum velocity, and ideal middle ears.

    Science.gov (United States)

    Peake, W T; Rosowski, J J

    1991-05-01

    One way to assess an ear's performance as a receiver of acoustic power is to consider impedance matching at the tympanic membrane. Assumptions about some of the impedances involved have lead to the idea of an optimum velocity magnitude (per unit pressure), which has been used as a test of middle-ear performance. We show that this approach is not a realistic way to assess effectiveness of power absorption at the tympanic membrane. More generally, we suggest that, if the performance of the combined external-and-middle ear in collecting acoustic power and delivering it to the inner ear is considered, the external- and middle-ear power-transfer efficiencies, as well as impedance matching, are involved in relating performance to an ideal.

  13. Travel Inside the Ear

    Medline Plus

    Full Text Available ... Search form Search A–Z Index Español Menu Home Health Info Hearing, Ear Infections, and Deafness Balance ... Committees Contact Us Get Involved You are here Home » Health Info » Hearing, Ear Infections, and Deafness Travel ...

  14. "Swimmer's Ear" (Otitis Externa) Prevention

    Science.gov (United States)

    ... infections, swimmer’s ear, and healthy swimming. "Swimmer's Ear" (Otitis Externa) What are the symptoms of swimmer's ear? ... Healthy page. Reference CDC. Estimated burden of acute otitis externa —United States, 2003–2007 . MMWR Morb Mortal ...

  15. Ear - blocked at high altitudes

    Science.gov (United States)

    High altitudes and blocked ears; Flying and blocked ears; Eustachian tube dysfunction - high altitude ... eustachian tube is a connection between the middle ear (the space deep to the eardrum) and the ...

  16. Effects of acute infrasound exposure on vestibular and auditory functions and the ultrastructural changes of inner ear in the guinea pig%急性次声波暴露后豚鼠位听功能及内耳超微结构的变化

    Institute of Scientific and Technical Information of China (English)

    冯勃; 姜泗长; 杨伟炎; 韩东一; 张素珍

    2001-01-01

    目的观察次声波对豚鼠位听功能和内耳超微结构的影响。方法将豚鼠置于频率8 Hz、声压级135 dB SPL的次声声场中连续暴露90 min。应用正弦摆动试验(sinusoidal pendular test, SPT)、听性脑干反应(auditory brainstem response,ABR)和畸变产物耳声发射(distortion production otoacoustic emission,DPOAE)评价次声波暴露前后豚鼠前庭功能和听功能的变化,扫描电镜观察豚鼠内耳各结构表面超微形态的变化。结果次声波暴露后不同时间正弦摆动诱发的豚鼠前庭性眼震的最大慢相速度(slow-phase velocity, SPV)和频率较次声暴露前轻微降低,但无显著性意义(P>0.05)。次声波暴露后各组动物ABR阈值较正常时略有升高,亦无统计学差异(P>0.05),各组动物ABR各波潜伏期和波间期与次声暴露前比较差异均无显著性(P>0.05);DPOAE 的幅度值在各个频率段均有明显的降低(P0.05). No differences in the ABR thresholds, the latencies and the interval peak latencies of Ⅰ,Ⅲ,Ⅴ waves were found between the normal and the experimental groups, and among experimental groups. The amplitudes of DPOAE at any frequency declined remarkably in all experimental groups. The ultrastructures of the inner ear were damaged to different extent. Conclusion Infrasound could transiently depress the excitability of the vestibular end-organs, decrease the function of OHC in the organ of Corti and cause damage to the inner ear of guinea pigs.

  17. In vitro and in vivo studies on hydroxyapatite nanoparticles as a novel vector for inner ear gene therapy%用羟基磷灰石纳米粒作内耳基因治疗新载体的体内外研究

    Institute of Scientific and Technical Information of China (English)

    孙虹; 蒋明; 朱晒红

    2008-01-01

    Objective To assess the possibility of hydroxyapatite(HAT)nanoparticles as a gene vector for inner ear gene transfection.Methods The HAT nanoparticles were prepared by the precipitation hydrothermal technique. DNA binding test under series of pH values and HAT concentrations were carried out by means of DNA electrophoresis to show the DNA binding and protective effect of the HAT nanoparticles. The cytotoxicity of HAT was evaluated via methyhhiazolyl tetrazolium assay(MTT) test with cultured Hela cells. The in vitro green fluorescent protein(GFP) reported transfection test and neurotrophin 3(NT3) Western blot were completed with both Hela cells and primarily cultured mice cochlear neurons,so as to observe HAT mediated in vitro gene transfection efficiency and consequent NT3 gene expression. The complex consisting of HAT nanoparticles and recombinant plasmid with enhanced GFP and NT3 (HAT-pEGFPC2-NT3) was perfused perilymphatically into the cochlea of the guinea pigs with experimental excitotoxic inner ear damage. Inner ear NT3 gene expression was immunohistochemically demonstrated(DAB method)to evaluate the capability of HAT nanoparticles in mediating NT3 gene transfection in living animals and the possibility of future clinical application. Resuits When applied at the lowest concentration of 250 μg/ml and the pH values of 3-7,the 40-50 nm stick-shaped nanoparticles fully loaded the recombinant plasmid pEGFPC2-NT3,and well protected the genes from being destroyed by DNase Ⅰ. Well biocompatibility between HAT nanoparticles and the cultured Hela cells had been confirmed by methylthiazolyl tetrazolium assay(MTT) method when the concentration of HAT nanoparticles ranged from 62.5 μg/ml to 500 μg/ml. Immunoflourescence test of the report gene GFP revealed that the transfection efficiency of HAT nanoparticle vector in Hela cells was 15.7%±2.6%(-x±s). EGFP was immunoflourescently expressed by transfection of HAT-pEGFPC2-NT3 in the primarily cultured cochlear neurons

  18. The canparative study of small inner ear malformation of sensorineural hearing loss chuldren and norraul children of the comparis%微小内耳畸形的感音神经性耳聋患儿与正常儿童内耳HRCT标准化测量的对比研究

    Institute of Scientific and Technical Information of China (English)

    刘军; 李长勤

    2016-01-01

    目的:探讨内耳HRCT标准化测量对微小内耳畸形的先天性感音神经性耳聋( SNHL)患儿与正常儿童内耳解剖的价值。方法对32例无明显影像学内耳畸形的先天性SNHL患儿和76例正常儿童行颞骨HRCT检查,标准化测量上半规管、外半规管及后半规管的骨管及骨岛的宽度、耳蜗的最大高度和宽度、前庭的最大宽度和长度等。采用SPSS 13.0统计软件的t检验比较实验组与正常组测量数据差异。结果两组数据在外半规管骨岛的宽度( lateral semicircular canal, LSCC),正常组:(3.06±0.36)mm、SNHL组:(3.03±0.03)mm、耳蜗的最大高度,正常:(4.46±0.11)mm、SNHL组:(4.51±0.09)、上半规管骨岛宽度(superior semicircular canal, SSCC),正常:(4.54±0.39)mm、SNHL组:(4.32±0.45) mm之间有明显的差异( P <0.05)。 SNHL患儿的外半规管骨岛宽度、上半规管骨岛宽度测量值均小于正常儿童(3.03±0.03)mm vs (3.06±0.36)mm,(4.32±0.45)mm vs (4.54±0.39)mm( Pp<0.05);耳蜗最大高度测量值大于正常儿童(4.51±0.09)mm vs (4.46±0.11)mm( P <0.05)。结论标准化HRCT测量上半规管、外半规管骨岛宽度及耳蜗最大高度可对先天性SNHL进行诊断。%Objective The purpose of this study is to use the HRCT standard measurement methods of the inner ear to observe the inner ear malformations in patients suffering from congenital deafness and to explore its diagnostic value in the diagnosis of con -genital sensorineural hearing loss .Methods The experimental group includes a total of 50 patients with congenital sensor neural hearing loss of the inner ear , while the control group included 152 normal inner ear scan image .The measurements of this study were in the axial CT scanned images to obtain the measurement data , Two senior radiologists used the double

  19. Swimmer's Ear (For Parents)

    Science.gov (United States)

    ... Child What Kids Say About: Handling Stress Anxiety, Fears, and Phobias Community Service: A Family's Guide to ... can drain into the ear canal through a hole in the eardrum and cause it. What Are ...

  20. Travel Inside the Ear

    Medline Plus

    Full Text Available Skip to main content U.S. Department of Health & Human Services National Institutes of Health Search Search form Search A–Z Index Español Menu Home Health Info Hearing, Ear Infections, and Deafness ...

  1. Flying and Your Child's Ears

    Science.gov (United States)

    ... Media Flying and Your Child's Ears KidsHealth > For Parents > Flying and Your Child's Ears Print A A A What's in this article? Flying's Effects on Ears Tips for Easing Ear Pain en español Como cuidar los oídos de su hijo(a) cuando vuele en avión Flying's Effects on ...

  2. The malleable middle ear: an underappreciated player in the evolution of hearing in vertebrates

    DEFF Research Database (Denmark)

    Christensen-Dalsgaard, Jakob

    2014-01-01

    The middle ear of tetrapods (limbed vertebrates) originated from nonauditory structures, and has been modified by adaptations arising from the lifestyle of the tetrapods. These accessory structures for the inner ear increased the sensitivity to airborne sound, the frequency range of hearing...

  3. Convergence vs. Specialization in the ear region of moles (Mammalia).

    Science.gov (United States)

    Crumpton, Nick; Kardjilov, Nikolay; Asher, Robert J

    2015-08-01

    We investigated if and how the inner ear region undergoes similar adaptations in small, fossorial, insectivoran-grade mammals, and found a variety of inner ear phenotypes. In our sample, afrotherian moles (Chrysochloridae) and the marsupial Notoryctes differ from most other burrowing mammals in their relatively short radii of semicircular canal curvature; chrysochlorids and fossorial talpids share a relatively long interampullar width. Chrysochlorids are unique in showing a highly coiled cochlea with nearly four turns. Extensive cochlear coiling may reflect their greater ecological dependence on low frequency auditory cues compared to talpids, tenrecids, and the marsupial Notoryctes. Correspondingly, the lack of such extensive coiling in the inner ear of other fossorial species may indicate a greater reliance on other senses to enable their fossorial lifestyle, such as tactile sensation from vibrissae and Eimer's organs. The reliance of chrysochlorids on sound is evident in the high degree of coiling and in the diversity of its mallear types, and may help explain the lack of any semiaquatic members of that group. The simplest mallear types among chrysochlorids are not present in the basal-most members of that clade, but all extant chrysochlorids investigated to date exhibit extensive cochlear coiling. The chrysochlorid ear region thus exhibits mosaic evolution; our data suggest that extensive coiling evolved in chrysochlorids prior to and independently of diversification in middle ear ossicle size and shape.

  4. Impact of Placement of In-the-Ear Antenna on Ear-to-Ear Path Gain

    DEFF Research Database (Denmark)

    Kammersgaard, Nikolaj Peter Iversen; Kvist, Søren H.; Thaysen, Jesper;

    2015-01-01

    An in-the-ear antenna is rotated in the concha. For the different placements the ear-to-ear path gain is simulated and measured. The simulations and measurements show that the ear-to-ear path gain varies with more than 15 dB even though it is the same antenna that occupies the same volume, which...... has only been rotated. This illustrates the importance of the correct placement of the antenna. The variation of the ear-to-ear path gain is compared with the far-field efficiency in order to explain part of the variation. The best and worst placements’ radiation patterns are analyzed....

  5. Ear, Hearing and Speech

    DEFF Research Database (Denmark)

    Poulsen, Torben

    2000-01-01

    An introduction is given to the the anatomy and the function of the ear, basic psychoacoustic matters (hearing threshold, loudness, masking), the speech signal and speech intelligibility. The lecture note is written for the course: Fundamentals of Acoustics and Noise Control (51001)......An introduction is given to the the anatomy and the function of the ear, basic psychoacoustic matters (hearing threshold, loudness, masking), the speech signal and speech intelligibility. The lecture note is written for the course: Fundamentals of Acoustics and Noise Control (51001)...

  6. Middle ear mucosal regeneration with three-dimensionally tissue-engineered autologous middle ear cell sheets in rabbit model.

    Science.gov (United States)

    Yaguchi, Yuichiro; Murakami, Daisuke; Yamato, Masayuki; Hama, Takanori; Yamamoto, Kazuhisa; Kojima, Hiromi; Moriyama, Hiroshi; Okano, Teruo

    2016-03-01

    The likelihood of recurrent retraction and adhesion of newly formed tympanic membrane is high when middle ear mucosa is extensively lost during cholesteatoma and adhesive otitis media surgery. If rapid postoperative regeneration of the mucosa on the exposed bone surface can be achieved, prevention of recurrent eardrum adhesion and cholesteatoma formation, for which there has been no definitive treatment, can be expected. Suture-less transplantation of tissue-engineered mucosal cell sheets was examined immediately after the operation of otitis media surgery in order to quickly regenerate middle ear mucosa lost during surgery in a rabbit model. Transplantable middle ear mucosal cell sheets with a three-dimensional tissue architecture very similar to native middle ear mucosa were fabricated from middle ear mucosal tissue fragments obtained in an autologous manner from middle ear bulla on temperature-responsive culture surfaces. Immediately after the mucosa was resected from middle ear bone bulla inner cavity, mucosal cell sheets were grafted at the resected site. Both bone hyperplasia and granulation tissue formation were inhibited and early mucosal regeneration was observed in the cell sheet-grafted group, compared with the control group in which only mucosal removal was carried out and the bone surface exposed. This result indicates that tissue engineered mucosal cell sheets would be useful to minimize complications after the surgical operation on otitis media and future clinical application is expected.

  7. Study on the Relationship between the Pathogenic Mutations of GJB2、SLC26A4 and CT Phenotypes of Inner Ear in Patient with Sensorineural Hearing Loss%GJB2、SLC26A4基因致病性突变与内耳CT表型关系的研究

    Institute of Scientific and Technical Information of China (English)

    孙宝春; 代志瑶; 黄莎莎; 韩冰; 袁永一; 苏钰; 康东洋; 戴朴

    2014-01-01

    Objects Study on the relationship between the pathogenic mutations of GJB2、SLC26A4 and CT pheno-types of inner ear. Explore the feasibility of using the method of gene sequence analysis to help CT examination in diagnosing of patients with inner ear malformation. Methods 2686 cases of patients were detected by GJB2 and SLC26A4 with the meth-od of DNA sequence. CT phenotypes of those patients were classified according to the method proposed by Sennaroglu. We analyzed the relationship between the pathogenic mutations of gene and the CT phenotypes. Results 1、429 cases were de-tected with pathogenic mutations of GJB2 (220 cases were homozygous, 207 cases were compound heterozygous and 2 case carried dominant mutation). 596 cases were detected with pathogenic mutations of SLC26A4 (169 cases were homozygous, 427 cases were compound heterozygous). 2、873 cases of inner ear malformations were diagnosed by CT examination(371 cas-es of Mondini malformation, 338 cases of enlarged vestibular aqueduct malformation and 164 cases of other types), normal was 1813 cases. 3、99.30%(426/429) cases carried pathogenic mutation of GJB2 were detected in the normal group and 100%(596/596)cases carried pathogenic mutation of SLC26A4 were detected in the group related to vestibular aqueduct malforma-tion. Conclusion The results suggested that pathogenic mutations of GJB2 is closely related to the CT phenotype of normal and pathogenic mutations of SLC26A4 is closely related to the CT phenotype of vestibular aqueduct malformation.%目的:研究感音神经耳聋GJB2、SLC26A4基因致病性突变与内耳CT表型之间的关系,探讨这两种基因检测在诊断感音神经性耳聋患者是否存在内耳畸形方面的作用。方法按DNA测序的方法检测2686例感音神经性耳聋患者GJB2、SLC26A4基因致病性突变情况,以Sennaroglu分类为标准统计以上患者内耳CT表型情况,分析GJB2、SLC26A4基因型与CT表型之间的关系。结果1、2686

  8. From Ear to Brain

    Science.gov (United States)

    Kimura, Doreen

    2011-01-01

    In this paper Doreen Kimura gives a personal history of the "right-ear effect" in dichotic listening. The focus is on the early ground-breaking papers, describing how she did the first dichotic listening studies relating the effects to brain asymmetry. The paper also gives a description of the visual half-field technique for lateralized stimulus…

  9. Seeing With the Ears

    NARCIS (Netherlands)

    Koenderink, Jan

    2015-01-01

    In recent talks, I mentioned how my artist friends often complain that their clients see with their ears. It recently dawned on me that nobody understood what I said, or—worse—got the wrong idea. The audience thinks of bionic devices (Proulx, Stoerig, Ludowig, & Knoll, 2008) or bat echo location (Mo

  10. Low-set ears and pinna abnormalities

    Science.gov (United States)

    Low-set ears; Microtia; "Lop" ear; Pinna abnormalities; Genetic defect-pinna; Congenital defect-pinna ... conditions: Abnormal folds or location of the pinna Low-set ears No opening to the ear canal ...

  11. Ear, Nose & Throat Issues & Down Syndrome

    Science.gov (United States)

    ... Throat Issues & Down Syndrome Ear, Nose & Throat Issues & Down Syndrome Ear, nose, and throat (ENT) problems are common ... What ENT Problems Are Common in Children With Down Syndrome? External Ear Canal Stenosis Stenotic ear canals (narrow ...

  12. The analysis of ear canals

    Science.gov (United States)

    Ou, Gen

    In this thesis complex 3-D ear canal finite element models are simplified using transfer matrices to 1-D models. This simplification allows analysis on the sound propagation in the ear, which results in potentially using a non-invasive probe to determine the acoustical properties of the ear.

  13. An abnormal portal blood flow in the inner ear

    DEFF Research Database (Denmark)

    Friis, Morten

    til Meniere's sygdom. Meniere's sygdom er en abnormalitet i det indre øre som er karakteriseret ved episodisk svimmelhed (vertigo), tinnitus, fluktuerende høretab og en følelse at tryk i det afficerede øre. Symptomerne er muligvis associeret med en defekt regulering af væskerne (endolymfe og perilymfe...

  14. Inner ear infections as cause of perinatal deafness

    Directory of Open Access Journals (Sweden)

    Vikas Gupta

    2012-01-01

    Full Text Available Objective: To assess the role of infective agents as cause of sensorineural hearing loss (SNHL in children. Setting: Tertiary care center actively involved in management of hearing impairment through cochlear implant program and other rehabilitation program. Materials and Methods: Retrospective chart review of 213 patients who underwent cochlear implantation at our center from 2007 to 2011 was carried out. Out of these, 185 were children. We have done the data analysis with regard to etiology of hearing loss in these 185 children. An etiology for SNHL could be established in 100 out of these 185 cases. Out of these 100 cases, we have further segregated cases where an infectious etiology was implicated. Results: Out of 185 prelingual cochlear implantees, etiology could be determined in 100 cases. Etiology was of infective origin in 26 of these 100 cases. Infective agents implicated in congenital acquired hearing loss were Toxoplasma, Rubella, Cytomegalovirus, and Herpes (TORCH infections ( n = 9 including Rubella ( n = 7 and Cytomegalovirus (CMV ( n = 2. Meningitis ( n = 11 and other infections ( n = 6 were responsible for secondary acquired hearing loss. Conclusions: Results showed that among the identified causes, infective agents were responsible in one-fourth cases of profound SNHL. Building awareness about such existence and their major role in causing SNHL among the otolaryngologists, pediatricians, obstetricians, physicians, audiologists and public is considered essential so that such preventable and controllable maladies are reduced by combined efforts from all these stakeholders.

  15. An abnormal portal blood flow in the inner ear

    DEFF Research Database (Denmark)

    Friis, Morten

    Den endolymfatiske sæk (saccus endolymphaticus), en del af det indre øre, har karakteristika som en endokrin kirtel og synes at producere et natriuretisk hormon, som tænkes at have en effekt på reguleringen af det indre øres væsker. En fejlregulering af væskerne i det indre øre er en mulig årsag ...

  16. Cell- and gene-therapy approaches to inner ear repair

    OpenAIRE

    Conde de Felipe, Magnolia; Feijoo-Redondo, Ana; García-Sancho, Javier; Schimmang, Thomas; Durán, Mercedes

    2011-01-01

    Sensorineural hearing loss is the most common sensory disorder in humans. It is primarily due to the degeneration of highly specialised mechanosensory cells in the cochlea, the so-called hair cells. Hearing problems can also be caused or further aggravated by the death of auditory sensory neurons that convey the information from the hair cells to the brain stem. Despite the discovery of stem/progenitor cells in the mammalian cochlea, no regeneration of either damaged hair cells or auditory ne...

  17. The contralateral ear in cholesteatoma.

    Science.gov (United States)

    da Costa, Sady Selaimen; Teixeira, Adriane Ribeiro; Rosito, Letícia Petersen Schmidt

    2016-07-01

    Middle ear cholesteatoma has been extensively studied. Theories of cholesteatoma pathogenesis involving previous tympanic membrane retraction are the most widely accepted, but the contralateral ear in patients with cholesteatoma remains unstudied. This study aimed to investigate the contralateral ear in patients with cholesteatoma, and to determine whether the characteristics of it differ according to patient age and cholesteatoma growth patterns. This study was cross sectional. We evaluated 356 patients with middle ear cholesteatoma in at least one ear, and no history of surgery, between August 2000 and March 2013. Otoendoscopy was conducted on both the affected and the contralateral ear. They were classified as normal, tympanic membrane perforation, moderate to severe tympanic membrane retraction and cholesteatoma. The mean age of the patients was 32.77 years, and 53.1 % of the cohort were female. Only 34.8 % of the contralateral ears were normal. The most common abnormality was moderate to severe tympanic membrane retraction (41.6 %). Cholesteatoma was identified in 16 %. Children exhibited a greater frequency of tympanic membrane retractions, whereas adults exhibited a greater frequency of cholesteatoma. All of the contralateral ears in the anterior epitympanic group were normal, but otherwise there were no differences in the contralateral ear when we compared the cholesteatoma growth patterns. We conclude that patients diagnosed with acquired cholesteatoma of one ear are significantly more likely to exhibit abnormalities of the contralateral ear.

  18. The ear in fetal MRI: what can we really see?

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Nuno Canto [Neuroradiology Section C., Campos Costa, Fragosela, Viseu (Portugal); Uppsala University, Department of Radiology, Uppsala (Sweden); Teixeira, Joao [Department of Neuroradiology, Porto (Portugal); Raininko, Raili; Wikstrom, Johan [Uppsala University, Department of Radiology, Uppsala (Sweden)

    2011-12-15

    The aim of this study was to investigate the ability to depict the components of the ear on brain-oriented fetal MRI studies. Retrospective evaluation of the ear in MRI studies was performed post-mortem in 16 fetuses ranging from 15 to 22 gestation weeks (GW), and in 122 examinations in vivo of fetuses ranging from 20 to 38 GW. The cochlea, vestibular apparatus, middle ear, and external auditory canal were separately graded according to the components that were delineated. The components of the inner and middle ear were fully delineated in 100% of the post-mortem examinations, but the external auditory canals were only seen in only 25%. In the in vivo group, the imaging detail was much lower. Cochlear turns could be identified in 75% of the fetuses, the vestibule and the lateral semicircular canals in 72% andossicles in 70%. Before 25 GW, the ability to identify these individual parts was 50%, 30%, and 33%, respectively, and above it was 89%, 93%, and 90%. In most cases, the external auditory canals could only be seen after 29 GW. In fetal MRI studies in vivo, it is possible to depict the components of the ear in the majority of the fetuses, in such a manner as to exclude major malformations. However, MRI might not provide enough detail to rule out pathology of the ear before 25 GW, this being a critical age for pregnancy management in many countries. (orig.)

  19. nEar 05

    Institute of Scientific and Technical Information of China (English)

    S&C Labs

    2005-01-01

    Ego Systems简称ESI或Ego-Sys,这问韩国公司一向以制造低价格、高性能的专业音频产品闻名于专业音频制作领域。其产品涵盖了专业录音卡、监听音箱和USB声卡等。在大家的印象中,可能还记得MAYA录音卡、nEar 08监听音箱,以及MAYA EX系列USB声卡。其中,nEar08监听音箱曾在本刊2001年第18期报道过,那是它首次在国内媒体上亮相。经过四年多的市场检验,

  20. 高压氧对肾上腺素诱导的内耳损伤大鼠听力及下丘脑-垂体-肾上腺轴激素水平的影响%Effects of hyperbaric oxygen on the hearing of inner ear and the hormone levels of HPA axis in rats induced by adrenaline

    Institute of Scientific and Technical Information of China (English)

    潘树义; 杨晨; 陈晓; 孟祥恩; 张良

    2014-01-01

    Objective To observe the effects of hyperbaric oxygen (HBO) on the damage of inner ear and hearing loss induced by adrenaline and also to monitor changes in hormone levels related with stress,so as to evaluate effects of HBO on hearing damage and related stressors.Methods Twenty-four male Wistar rats were randomly divided into 3 groups:the blank control group,the adrenaline group and the adrenaline plus HBO group.Infusion of adrenaline through the access of middle ear for a succession of 5 days till hearing loss was induced,while the animals in the control group were only given physiologic saline.After completion of medication,the animals in the HBO group received HBO therapy 1 session / a day for 3 consecutive days,and the animals in the other 2 groups were left untreated for natural recovery.Changes in hearing thresholds in rats were detected through monitoring of evoked auditory brainstem response (ABR).After termination of the experiment,the animals were sacrificed for detection of serum hormone levels.Results The administration of adrenaline through the access of middle ear could elevate the hearing threshold of the rats.The final hearing threshold of the rats in the HBO group [(26.01 ± 7.95) dB] was lower than that of the adrenaline group [(39.69 ± 8.26) dB] (P < 0.05).Cortisol level in the animals of the control group was the lowest,followed by the animals in the HBO group.The cortisol level in the animals of the model group was the highest.Conclusions HBO therapy could alleviate hearing damage of the rats induced by adrenaline.Cortical levels were closely associated with the seriousness of hearing damage.%目的 观察高压氧暴露对肾上腺素导致的大鼠内耳损伤、听力下降的影响,以及相关激素的改变情况,评价高压氧治疗对听力及激素水平的影响.方法 24只大鼠按数字表法随机分为3组:空白对照组、肾上腺素组、肾上腺素+高压氧组.肾上腺素组、肾上腺素+高压氧组连续5d经中

  1. INNER TRACKING

    CERN Multimedia

    P. Sharp

    The CMS Inner Tracking Detector continues to make good progress. The successful commissioning of ~ 25% of the Silicon Strip Tracker was completed in the Tracker Integration Facility (TIF) at CERN in July 2007 and the Tracker has since been prepared for moving and installation into CMS at P5. The Tracker was ready to move on schedule in September 2007. The Installation of the Tracker cooling pipes and LV cables between Patch Panel 1 (PP1) on the inside the CMS magnet cryostat, and the cooling plants and power system racks on the balconies has been completed. The optical fibres from PP1 to the readout FEDs in the USC have been installed, together with the Tracker cable channels, in parallel with the installation of the EB/HB services. All of the Tracker Safety, Power, DCS and the VME Readout Systems have been installed at P5 and are being tested and commissioned with CMS. It is planned to install the Tracker into CMS before Christmas. The Tracker will then be connected to the pre-installed services on Y...

  2. INNER TRACKING

    CERN Multimedia

    P. Sharp

    The CMS Inner Tracking Detector continues to make good progress. The Objective for 2006 was to complete all of the CMS Tracker sub-detectors and to start the integration of the sub-detectors into the Tracker Support Tube (TST). The Objective for 2007 is to deliver to CMS a completed, installed, commissioned and calibrated Tracking System (Silicon Strip and Pixels) aligned to < 100µ in April 2008 ready for the first physics collisions at LHC. In November 2006 all of the sub-detectors had been delivered to the Tracker Integration facility (TIF) at CERN and the tests and QA procedures to be carried out on each sub-detector before integration had been established. In December 2006, TIB/TID+ was integrated into TOB+, TIB/TID- was being prepared for integration, and TEC+ was undergoing tests at the final tracker operating temperature (-100 C) in the Lyon cold room. In February 2007, TIB/TID- has been integrated into TOB-, and the installation of the pixel support tube and the services for TI...

  3. INNER TRACKER

    CERN Multimedia

    P. Sharp

    The CMS Inner Tracking Detector continues to make good progress. The Objective for 2007 is to deliver to CMS a completed, installed, commissioned and calibrated Tracking System (Silicon Strip and Pixels) aligned to < 100µ in April 2008 ready for the first physics collisions at LHC. On 21 March 2007, the integration of the CMS Silicon Strip Tracker was completed with the successful integration of TEC- into the Tracker Support Tube (TST). Since then ~25% of the complete Tracker Systems has been commission at the TIF at both room temperature and operating temperature (-100 C), and the Tracker Community has gained very valuable experience in operating, calibrating and aligning the Tracker at the TIF before it is prepared for transportation to P5 in July 2007. The CMS Pixel System continues to make good progress. Module and Plaquette production is very well advanced. The first 25% of the Forward Pixel detector (Fpix) was delivered to CERN in April and the second 25% will shipped to CERN on 19 ...

  4. INNER TRACKING

    CERN Multimedia

    P. Sharp

    The CMS Inner Tracking Detector continues to make good progress. The successful commissioning of ~ 25% of the Silicon Strip Tracker was completed in the Tracker Integration Facility (TIF) at CERN on 18 July 2007 and the Tracker has since been prepared for moving and installation into CMS at P5. The Tracker will be ready to move on schedule in September 2007. The Installation of the Tracker cooling pipes and LV cables between Patch Panel 1 (PP1) on the inside the CMS magnet cryostat, and the cooling plants and power system racks on the balconies has been completed. The optical fibres from PP1 to the readout FEDs in the USC will be installed in parallel with the installation of the EB/HB services, and will be completed in October. It is planned to install the Tracker into CMS at the end of October, after the completion of the installation of the EB/HB services. The Tracker will then be connected to the pre-installed services on YB0 and commissioned with CMS in December. The FPix and BPix continue to make ...

  5. Ear Recognition Based on Gabor Features and KFDA

    OpenAIRE

    Li Yuan; Zhichun Mu

    2014-01-01

    We propose an ear recognition system based on 2D ear images which includes three stages: ear enrollment, feature extraction, and ear recognition. Ear enrollment includes ear detection and ear normalization. The ear detection approach based on improved Adaboost algorithm detects the ear part under complex background using two steps: offline cascaded classifier training and online ear detection. Then Active Shape Model is applied to segment the ear part and normalize all the ear images to the s...

  6. The ear: Diagnostic imaging

    Energy Technology Data Exchange (ETDEWEB)

    Vignaud, J.; Jardin, C.; Rosen, L.

    1986-01-01

    This is an English translation of volume 17-1 of Traite de radiodiagnostic and represents a reasonably complete documentation of the diseases of the temporal bone that have imaging manifestations. The book begins with chapters on embryology, anatomy and radiography anatomy; it continues with blood supply and an overview of temporal bone pathology. Subsequent chapters cover malformations, trauma, infections, tumors, postoperative changes, glomus tumors, vertebasilar insufficiency, and facial nerve canal lesions. A final chapter demonstrates and discusses magnetic resonance images of the ear and cerebellopontine angle.

  7. MicroRNAs in sensorineural diseases of the ear

    Directory of Open Access Journals (Sweden)

    Kathy eUshakov

    2013-12-01

    Full Text Available Non-coding microRNAs have a fundamental role in gene regulation and expression in almost every multicellular organism. Only discovered in the last decade, microRNAs are already known to play a leading role in many aspects of disease. In the vertebrate inner ear, microRNAs are essential for controlling development and survival of hair cells. Moreover, dysregulation of microRNAs has been implicated in sensorineural hearing impairment, as well as in other ear diseases such as cholesteatomas, vestibular schwannomas and otitis media. Due to the inaccessibility of the ear in humans, animal models have provided the optimal tools to study microRNA expression and function, in particular mice and zebrafish. A major focus of current research has been to discover the targets of the microRNAs expressed in the inner ear, in order to determine the regulatory pathways of the auditory and vestibular systems. The potential for microRNA manipulation in development of therapeutic tools for hearing impairment is as yet unexplored, paving the way for future work in the field.

  8. MICROBIOLOGY OF ITCHY EARS

    Directory of Open Access Journals (Sweden)

    Vijin Ravindran Nambiar

    2015-04-01

    Full Text Available Objective: To study microbiology of external auditory canal in patients with itchy ears and to also study susceptibility profiles of pathogenic organisms to aid in appropriate management. Materials & Methods: A total of hundred patients were selected. An external ear canal swab was taken. For recovery of bacteria, the samples were emulsified in a solution of BHI broth to study aerobic and anaerobic bacteria. Fungal microbiology was studied by KOH mount and fungal culture. Culture and sensitivity was done for the pathogenic organisms. Results: Of the total hundred patients, 48% patients had no growth. There were no anaerobes isolated. Of the remaining 52% cases, 33% of the growth was aerobic bacteria and 19% of the growth was fungi. Of the aerobic bacteria, coagulase negative staphylococcus was isolated from 22 patients, staphylococcus aureus from 9 patients and pseudomonas aeruginosa from 2 patients. Of the fungal species, candida was isolated from 11 patients and aspergillus niger from 8 patients. Conclusion: Our study concluded that there need not be an underlying bacterial or fungal infection to cause itching as evidenced by a condition called asteatosis. Hence, asteatosis should be considered as one of the differential diagnosis for chronic and persistent itching when all other causes have been ruled out. We also found that topical ciprofloxacin drops is equally effective against the common bacterial pathogens.

  9. Laser interferometric vibration measurements of the middle ear in healthy humans

    Science.gov (United States)

    Jorge, J. Rodriguez; Hemmert, Werner; Burkhardt, Claus; Zenner, Hans-Peter; Gummer, Anthony W.

    1996-01-01

    The use of spontaneous and evoked otacoustic emissions is now a standard clinical tool for diagnosis of the function of the inner ear. However, it is not possible to extract this information over the entire, functionally relevant frequency range because of imperfect coupling of: (1) stapedial to ear-drum vibrations through the ossicular chain of the middle ear and (2) ear-drum vibrations to air in the external auditory meatus. The problem could be circumvented if it were possible to measure the vibration of the stapes and ear drum. The ear drum can be visualized non-invasively, whereas the stapes is only accessible intra-operatively. Therefore, we designed a laser-interferometric system to non-invasively measure the vibration of the human ear drum. Vibrations were measured with a laser Doppler velocimeter (Polytec OFV-302) coupled into the side arm of an operating microscope (Zeiss OPMI MDM). The wavelength was 633 nm and emitted power was less than 1 mW. Direct coupling through the optics of the operating microscope, instead of through glass fibers, enabled a larger signal-to- noise ratio (20 - 30 dB) due to collection of more reflected light. This coupling scheme avoids the problems associated with having to place a reflecting material on the ear drum. The developed vibration measurement system allows non-invasive, fast and reproducible characterization of the dynamics of the human ear drum and as such can be used for clinical diagnostics.

  10. Standardized surgical approaches to ear surgery in rats

    Institute of Scientific and Technical Information of China (English)

    Peng Li; Dalian Ding; Kelei Gao; Richard Salvi

    2015-01-01

    Objective:To describe several approaches of ear surgeries for experimental studies in rats. Methods:Anesthetized rats were prepared for demonstration of various ear surgery approaches designed to optimize experimental outcomes in studies with specific goals and exposure requirements. The surgical approaches included the posterior tympanum, superior tympanum, inferior tympanum and occipital approaches. Results: The middle ear cavity and inner ear were successfully exposed from different angles via the mentioned surgical approaches. For example, electrode placement for recording of cochlear bioelectric responses was easily achieved through the posterior tympanum or inferior tympanum approach. Alternatively, drug delivery or gene transfection via round window membrane was most easily accomplished using the posterior tympanum approach. Cochlear perfusion of protective or ototoxic drugs was best performed using the inferior tympanum approach. Ossicular chain interruption to induce a prolonged conductive hearing loss was readily achieved using a superior tympanum approach. Lastly, surgical destruction of the endolymphatic sac to induce experimental endolymphatic hydrops was readily performed via an occipital surgical approach. Conclusion: These standardized surgical approaches can be applied in scientific studies of the ear with different purposes covering electro-physiology, conductive hearing loss, intra-cochlear drug perfusion and experimental studies relevant to Meniere's disease.

  11. 一氧化氮合酶3种异构体在豚鼠耳蜗的定位表达及其内耳听觉过程中的作用%Localization and expression of three nitric oxide synthase isoforms in the cochlea of guinea pigs and the effects in the hearing process of inner ear

    Institute of Scientific and Technical Information of China (English)

    王爱梅; 汤浩; 张仲明; 李连明; 牟华

    2005-01-01

    physiology and pathophysiology of inner ear.DESIGN: An observed and controlled study.SETTING: Department of Physiology, Jinzhou Medical College; Department of Orthopedics, the Second Affiliated Hospital of Jinzhou; Department of Otorhinolaryngology, Jinzhou Central Hospital.MATERIALS: The study was performed in Hearing Research Laboratory of China Medical University from May to November 2000. Ten healthy male albino guinea pigs, with body mass of 250-300 g, with sensitive Preyer's reflexes and normal drum membrane and external auditory canal,were selected.METHODS: After anesthesia, guinea pigs were decapitated and the temporal bones were removed immediately. The round and oval windows were opened, perfused with 40 g/L paraformaldehyde, and the specimens were immersed in the same fixative solution for 2 hours. Decalcification of the cochleae was performed in 100 g/L EDTA solution for 1 week. Then the specimens were placed in 250 g/L sucrose solution overnight and embedded in OCT. Cryostat (20 μm) sections were prepared for immunohistochemistry.MAIN OUTCOME MEASURES: Localization and expression of three NOS isoforms in the cochlea of guinea pigs.RESULTS: All data of ten guinea pigs was entered the final analysis without any loss. [1] Neuronal-type nNOS and endothelial-type eNOS immunoreactivity were localized in inner and outer hair cells of the organ of Corti, as well as in spiral ganglion cells. In addition, staining for nNOS and eNOS were also seen in the marginal cells of stria vascularis, spiral ligament cells, and in nerve fibers. [2] Inducible-type iNOS immunoreactivity was also detected in above each structure of the guinea pig cochlea under physiological conditions.CONCLUSION:NO may play an important role in neurotransmission,blood flow regulation, and cytotoxicity.

  12. Investigation of the ear-to-ear radio propagation channel

    DEFF Research Database (Denmark)

    Kvist, Søren Helstrup; Thaysen, J; Jakobsen, Kaj Bjarne

    2011-01-01

    The effect of the head size on the ear-to-ear radio propagation channel as a part of a body-centric wireless network is examined. The channel quality is evaluated at 2:45 GHz in terms of path gain (∣S21∣) between two monopole antennas that are placed normal to the surface of the head. The investi......The effect of the head size on the ear-to-ear radio propagation channel as a part of a body-centric wireless network is examined. The channel quality is evaluated at 2:45 GHz in terms of path gain (∣S21∣) between two monopole antennas that are placed normal to the surface of the head...

  13. Human ear recognition by computer

    CERN Document Server

    Bhanu, Bir; Chen, Hui

    2010-01-01

    Biometrics deals with recognition of individuals based on their physiological or behavioral characteristics. The human ear is a new feature in biometrics that has several merits over the more common face, fingerprint and iris biometrics. Unlike the fingerprint and iris, it can be easily captured from a distance without a fully cooperative subject, although sometimes it may be hidden with hair, scarf and jewellery. Also, unlike a face, the ear is a relatively stable structure that does not change much with the age and facial expressions. ""Human Ear Recognition by Computer"" is the first book o

  14. Outcomes in Endoscopic Ear Surgery.

    Science.gov (United States)

    Kiringoda, Ruwan; Kozin, Elliott D; Lee, Daniel J

    2016-10-01

    Endoscopic ear surgery (EES) provides several advantages compared with traditional binocular microscopy, including a wide-field view, improved resolution with high magnification, and visual access to hidden corridors of the middle ear. Although binocular microscopic-assisted surgical techniques remain the gold standard for most otologists, EES is slowly emerging as a viable alternative for performing otologic surgery at several centers in the United States and abroad. In this review, we evaluate the current body of literature regarding EES outcomes, summarize our EES outcomes at the Massachusetts Eye and Ear Infirmary, and compare these results with data for microscopic-assisted otologic surgery.

  15. Ear-body lift and a novel thrust generating mechanism revealed by the complex wake of brown long-eared bats (Plecotus auritus).

    Science.gov (United States)

    Johansson, L Christoffer; Håkansson, Jonas; Jakobsen, Lasse; Hedenström, Anders

    2016-04-27

    Large ears enhance perception of echolocation and prey generated sounds in bats. However, external ears likely impair aerodynamic performance of bats compared to birds. But large ears may generate lift on their own, mitigating the negative effects. We studied flying brown long-eared bats, using high resolution, time resolved particle image velocimetry, to determine the aerodynamics of flying with large ears. We show that the ears and body generate lift at medium to cruising speeds (3-5 m/s), but at the cost of an interaction with the wing root vortices, likely reducing inner wing performance. We also propose that the bats use a novel wing pitch mechanism at the end of the upstroke generating thrust at low speeds, which should provide effective pitch and yaw control. In addition, the wing tip vortices show a distinct spiraling pattern. The tip vortex of the previous wingbeat remains into the next wingbeat and rotates together with a newly formed tip vortex. Several smaller vortices, related to changes in circulation around the wing also spiral the tip vortex. Our results thus show a new level of complexity in bat wakes and suggest large eared bats are less aerodynamically limited than previous wake studies have suggested.

  16. Analysis of chick (Gallus gallus middle ear columella formation

    Directory of Open Access Journals (Sweden)

    Mercer Kathryn J

    2010-02-01

    Full Text Available Abstract Background The chick middle ear bone, the columella, provides an accessible model in which to study the tissue and molecular interactions necessary for induction and patterning of the columella, as well as associated multiple aspects of endochondral ossification. These include mesenchymal condensation, chondrogenesis, ossification of the medial footplate and shaft, and joint formation between the persistent cartilage of the extracolumella and ossified columella. Middle and external ear defects are responsible for approximately 10% of congenital hearing defects. Thus, understanding the morphogenesis and the molecular mechanisms of the formation of the middle ear is important to understanding normal and abnormal development of this essential component of the hearing apparatus. Results The columella, which arises from proximal ectomesenchyme of the second pharyngeal arch, is induced and patterned in a dynamic multi-step process. From the footplate, which inserts into the inner ear oval window, the shaft spans the pneumatic middle ear cavity, and the extracolumella inserts into the tympanic membrane. Through marker gene and immunolabeling analysis, we have determined the onset of each stage in the columella's development, from condensation to ossification. Significantly, a single condensation with the putative shaft and extracolumella arms already distinguishable is observed shortly before initiation of five separate chondrogenic centers within these structures. Ossification begins later, with periosteum formation in the shaft and, unexpectedly, a separate periosteum in the footplate. Conclusions The data presented in this study document the spatiotemporal events leading to morphogenesis of the columella and middle ear structures and provide the first gene expression data for this region. These data identify candidate genes and facilitate future functional studies and elucidation of the molecular mechanisms of columella formation.

  17. Global Ear. Werke 2001 - 2006

    Index Scriptorium Estoniae

    2006-01-01

    Dresdenis muusikafestivalil "Global Ear" 23.3.03 esitusel Eesti heliloojate muusika: Helena Tulve "lumineux/opaque", Jaan Rääts "Meditation", Mirjam Tally "Aura", Mati Kuulberg "Sonate Nr.4", Mari Vihmand "Seitsmele"

  18. Global Ear. Werke 2001 - 2006

    Index Scriptorium Estoniae

    2006-01-01

    Dresdenis muusikafestivalil "Global Ear" 23.3.03 esitusel Eesti heliloojate muusika: Helena Tulve "lumineux/opaque", Jaan Rääts "Meditation", Mirjam Tally "Aura", Mati Kuulberg "Sonate Nr.4", Mari Vihmand "Seitsmele"

  19. Multiple Osteomas in Middle Ear

    Directory of Open Access Journals (Sweden)

    Yongxin Li

    2012-01-01

    Full Text Available Since the first description of middle ear osteomas by Thomas in 1964, only few reports were published within the English literatures (Greinwalid et al., 1998; Shimizu et al., 2003; Cho et al., 2005; and Jang et al., 2009, and only one case of the multiple osteomas in middle ear was described by Kim et al., 2006, which arose from the promontory, lateral semicircular canal, and epitympanum. Here we describe a patient with multiple middle ear osteomas arising from the promontory, incus, Eustachian tube, and bony semicanal of tensor tympani muscle. This patient also contracted the chronic otitis media in the ipsilateral ear. The osteomas were successfully removed by performing type III tympanoplasty in one stage.

  20. 21 CFR 870.2710 - Ear oximeter.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ear oximeter. 870.2710 Section 870.2710 Food and... CARDIOVASCULAR DEVICES Cardiovascular Monitoring Devices § 870.2710 Ear oximeter. (a) Identification. An ear... ear. The amount of reflected or scattered light as indicated by this device is used to measure...

  1. Clinical characteristics of patients with labyrinthine fistulae caused by middle ear cholesteatoma

    Institute of Scientific and Technical Information of China (English)

    YANG Juan-mei; CHI Fang-lu; HAN Zhao; HUANG Yi-bo; LI Yi-ke

    2013-01-01

    Background Labyrinthine fistula (LF) is a very common clinical complication mainly caused by middle ear cholesteatoma.Whether the presence of different degree LF caused by middle ear cholesteatoma aggravates neurosensory hearing loss (NSHL) and what is the degree of the hearing loss caused by LF were still under controversial.This study aimed to investigate whether the LF degree is correlative with the age distribution,disease duration and hearing loss degree for cholesteatomatous patients.Methods The files of 143 patients with middle ear cholesteatoma were selected and reviewed in a retrospective study.Seventy-eight patients with LF were divided into three types according to the degree of destruction of labyrinth.Sixty-five patients without LF were randomly chosen for control.Then,we compared the clinical characteristics of patients with or without labyrinthine fistulae caused by middle ear cholesteatoma.Results According to the study,cholesteatomatous patients with LF were older and suffered longer disease duration than those without LF.Hearing loss is severe with high frequencies both in patients with and without LF.Moreover,inner ear impairment is correlative with the degree of destruction in labyrinth,and more severe destruction in labyrinth follow the more severe symptoms correlative with inner ear impairment.Conclusion Surgical intervention should be performed as eady as possible for these cholesteatomatous patients.

  2. 3D Printed Bionic Ears

    Science.gov (United States)

    Mannoor, Manu S.; Jiang, Ziwen; James, Teena; Kong, Yong Lin; Malatesta, Karen A.; Soboyejo, Winston O.; Verma, Naveen; Gracias, David H.; McAlpine, Michael C.

    2013-01-01

    The ability to three-dimensionally interweave biological tissue with functional electronics could enable the creation of bionic organs possessing enhanced functionalities over their human counterparts. Conventional electronic devices are inherently two-dimensional, preventing seamless multidimensional integration with synthetic biology, as the processes and materials are very different. Here, we present a novel strategy for overcoming these difficulties via additive manufacturing of biological cells with structural and nanoparticle derived electronic elements. As a proof of concept, we generated a bionic ear via 3D printing of a cell-seeded hydrogel matrix in the precise anatomic geometry of a human ear, along with an intertwined conducting polymer consisting of infused silver nanoparticles. This allowed for in vitro culturing of cartilage tissue around an inductive coil antenna in the ear, which subsequently enables readout of inductively-coupled signals from cochlea-shaped electrodes. The printed ear exhibits enhanced auditory sensing for radio frequency reception, and complementary left and right ears can listen to stereo audio music. Overall, our approach suggests a means to intricately merge biologic and nanoelectronic functionalities via 3D printing. PMID:23635097

  3. 3D printed bionic ears.

    Science.gov (United States)

    Mannoor, Manu S; Jiang, Ziwen; James, Teena; Kong, Yong Lin; Malatesta, Karen A; Soboyejo, Winston O; Verma, Naveen; Gracias, David H; McAlpine, Michael C

    2013-06-12

    The ability to three-dimensionally interweave biological tissue with functional electronics could enable the creation of bionic organs possessing enhanced functionalities over their human counterparts. Conventional electronic devices are inherently two-dimensional, preventing seamless multidimensional integration with synthetic biology, as the processes and materials are very different. Here, we present a novel strategy for overcoming these difficulties via additive manufacturing of biological cells with structural and nanoparticle derived electronic elements. As a proof of concept, we generated a bionic ear via 3D printing of a cell-seeded hydrogel matrix in the anatomic geometry of a human ear, along with an intertwined conducting polymer consisting of infused silver nanoparticles. This allowed for in vitro culturing of cartilage tissue around an inductive coil antenna in the ear, which subsequently enables readout of inductively-coupled signals from cochlea-shaped electrodes. The printed ear exhibits enhanced auditory sensing for radio frequency reception, and complementary left and right ears can listen to stereo audio music. Overall, our approach suggests a means to intricately merge biologic and nanoelectronic functionalities via 3D printing.

  4. 3D finite element model of the chinchilla ear for characterizing middle ear functions.

    Science.gov (United States)

    Wang, Xuelin; Gan, Rong Z

    2016-10-01

    Chinchilla is a commonly used animal model for research of sound transmission through the ear. Experimental measurements of the middle ear transfer function in chinchillas have shown that the middle ear cavity greatly affects the tympanic membrane (TM) and stapes footplate (FP) displacements. However, there is no finite element (FE) model of the chinchilla ear available in the literature to characterize the middle ear functions with the anatomical features of the chinchilla ear. This paper reports a recently completed 3D FE model of the chinchilla ear based on X-ray micro-computed tomography images of a chinchilla bulla. The model consisted of the ear canal, TM, middle ear ossicles and suspensory ligaments, and the middle ear cavity. Two boundary conditions of the middle ear cavity wall were simulated in the model as the rigid structure and the partially flexible surface, and the acoustic-mechanical coupled analysis was conducted with these two conditions to characterize the middle ear function. The model results were compared with experimental measurements reported in the literature including the TM and FP displacements and the middle ear input admittance in chinchilla ear. An application of this model was presented to identify the acoustic role of the middle ear septa-a unique feature of chinchilla middle ear cavity. This study provides the first 3D FE model of the chinchilla ear for characterizing the middle ear functions through the acoustic-mechanical coupled FE analysis.

  5. Investigation of the ear-to-ear radio propagation channel

    DEFF Research Database (Denmark)

    Kvist, Søren Helstrup; Thaysen, J; Jakobsen, Kaj Bjarne

    2011-01-01

    The effect of the head size on the ear-to-ear radio propagation channel as a part of a body-centric wireless network is examined. The channel quality is evaluated at 2:45 GHz in terms of path gain (∣S21∣) between two monopole antennas that are placed normal to the surface of the head. The investi......The effect of the head size on the ear-to-ear radio propagation channel as a part of a body-centric wireless network is examined. The channel quality is evaluated at 2:45 GHz in terms of path gain (∣S21∣) between two monopole antennas that are placed normal to the surface of the head....... The investigation is done by SAM head phantom measurements and HFSS simulations. The investigations include setups where some propagation paths are blocked by an absorbing material. It is found that the characteristics of the head may cause constructive or destructive interference that may result in up to 10 d...

  6. Interconnections between the Ears in Nonmammalian Vertebrates

    DEFF Research Database (Denmark)

    Feng, Albert S.; Christensen-Dalsgaard, J.

    2010-01-01

    Many of the nonmammalian vertebrates (anurans, lizards, crocodiles, and some bird species) have large, continuous air spaces connecting the middle ears and acoustically coupling the eardrums. Acoustical coupling leads to strongly enhanced directionality of the ear at frequencies where diffraction...

  7. Middle ear infection (otitis media) (image)

    Science.gov (United States)

    Otitis media is an inflammation or infection of the middle ear. Acute otitis media (acute ear infection) occurs when there is ... which causes production of fluid or pus. Chronic otitis media occurs when the eustachian tube becomes blocked ...

  8. DESING OF CYLINDIRICAL EAR OF POLISH

    Directory of Open Access Journals (Sweden)

    Yaşar KARAGÖZ

    2000-02-01

    Full Text Available Plough is an agricultural tool which is used for preparing land to male it ready for sowing. The funotion of lough is to break the compact land into small pieces and to allow a suitable condition for living of culture plants. The ear is the most important part of active plough surface. The geometrical form of ear determines the form of active surface together with the front iron tip. Ploughs are divided into two categories which are European and American types. There are important differencies betucen the European and American tyges with respect to ?, ß and ? angles. Gorjatschkin described the ear form of European ploughs under four main groups which are: 1. Cylindirical ear type, 2. Culture-form ear type, 3. Semi-curled ear type, 4. Curled ear type. In this work, the designing of cylindirical ear was studied.

  9. COMMON INFECTIONS OF THE EAR

    African Journals Online (AJOL)

    Enrique

    April 2004 Vol.22 No.4 CME. 193. KAREN COHEN. MB ChB ... the ear canal and they are usually in the 40 - 50-year age group. ... Treatment. The treatment of choice is intravenous antibiotics consisting of aminoglyco- side, piperacillin and ...

  10. Ear recognition based on Gabor features and KFDA.

    Science.gov (United States)

    Yuan, Li; Mu, Zhichun

    2014-01-01

    We propose an ear recognition system based on 2D ear images which includes three stages: ear enrollment, feature extraction, and ear recognition. Ear enrollment includes ear detection and ear normalization. The ear detection approach based on improved Adaboost algorithm detects the ear part under complex background using two steps: offline cascaded classifier training and online ear detection. Then Active Shape Model is applied to segment the ear part and normalize all the ear images to the same size. For its eminent characteristics in spatial local feature extraction and orientation selection, Gabor filter based ear feature extraction is presented in this paper. Kernel Fisher Discriminant Analysis (KFDA) is then applied for dimension reduction of the high-dimensional Gabor features. Finally distance based classifier is applied for ear recognition. Experimental results of ear recognition on two datasets (USTB and UND datasets) and the performance of the ear authentication system show the feasibility and effectiveness of the proposed approach.

  11. Ear Recognition Based on Gabor Features and KFDA

    Directory of Open Access Journals (Sweden)

    Li Yuan

    2014-01-01

    Full Text Available We propose an ear recognition system based on 2D ear images which includes three stages: ear enrollment, feature extraction, and ear recognition. Ear enrollment includes ear detection and ear normalization. The ear detection approach based on improved Adaboost algorithm detects the ear part under complex background using two steps: offline cascaded classifier training and online ear detection. Then Active Shape Model is applied to segment the ear part and normalize all the ear images to the same size. For its eminent characteristics in spatial local feature extraction and orientation selection, Gabor filter based ear feature extraction is presented in this paper. Kernel Fisher Discriminant Analysis (KFDA is then applied for dimension reduction of the high-dimensional Gabor features. Finally distance based classifier is applied for ear recognition. Experimental results of ear recognition on two datasets (USTB and UND datasets and the performance of the ear authentication system show the feasibility and effectiveness of the proposed approach.

  12. Can Loud Music Hurt My Ears?

    Science.gov (United States)

    ... or Too Short All About Puberty Can Loud Music Hurt My Ears? KidsHealth > For Kids > Can Loud Music Hurt My Ears? Print A A A en ... up? Oh! You want to know if loud music can hurt your ears . Are you asking because ...

  13. 21 CFR 878.3590 - Ear prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ear prosthesis. 878.3590 Section 878.3590 Food and... GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3590 Ear prosthesis. (a) Identification. An ear prosthesis is a silicone rubber solid device intended to be implanted to reconstruct the...

  14. Can Loud Music Hurt My Ears?

    Science.gov (United States)

    ... What Happens in the Operating Room? Can Loud Music Hurt My Ears? KidsHealth > For Kids > Can Loud Music Hurt My Ears? A A A en español ... up? Oh! You want to know if loud music can hurt your ears . Are you asking because ...

  15. Blackbody for metrological control of ear thermometers

    Science.gov (United States)

    Cárdenas-García, D.; Méndez-Lango, E.

    2013-09-01

    Body temperature is an important parameter in medical practice, and most of health diagnoses are made based upon measured temperature values. Non-contact measurements are attractive to both patients and physicians, and ear thermometers (ET) are part of the set of infrared thermometers for medical applications. ETs sense the tympanic membrane temperature which best represents body temperature. They take advantage of the natural high effective emissivity cavity that is formed as radiation source. To calibrate or to check the performance of ETs, we designed a high-emissivity spherical cavity as a blackbody source which can be placed in a dry block oven. Although the blackbody cavity can have any shape, we decided to build it spherical because its effective emissivity can be easily calculated in a closed form. The cavity is made of Aluminum to take advantage of its high thermal conductivity while its inner side is covered with a black paint to increase the cavity effective emissivity. Based on paint emissivity measurements and the geometrical shape, we calculated that the cavity has an effective emissivity higher than 0.999. Blackbody temperature is measured with a calibrated contact thermometer placed inside the bottom wall of the cavity. We present the design of the cavity, the experimental setup, and results of three commercial ETs compared with this cavity.

  16. Carcinoid tumour of the middle ear

    LENUS (Irish Health Repository)

    Baig, Salman

    2012-09-01

    A case of middle ear mass in a young female from Ireland is described, who presented with left ear hearing loss and intermittent bloody discharge from the same ear. Examination under microscope revealed occlusive polyp in the left ear and a biopsy had been taken under general anaesthesia. Histopathology report described an adenoma \\/ carcinoid tumour of the middle ear confirmed by positive immunohistochemical staining. CT temporal bones revealed the extension of the disease. The patient underwent left tympanotomy and excision of the tumour. In general, these tumours are regarded as benign but may be mistaken for adenocarcinomas because of their histological heterogenecity.

  17. A Survey on Human Ear Recognition

    Directory of Open Access Journals (Sweden)

    Suvarnsing Bhable

    2015-11-01

    Full Text Available This paper presents an efficient ear recognition technique which derives benefits from the local features of the ear and attempt to handle the problems due to pose, poor contrast, change in illumination and lack of registration. Recognizing humans by their ear have recently received significant attention in the field of research. Ear is the rich in characteristics. This paper provides a detailed survey of research done in ear detection and recognition. This survey paper is very useful in the current state-of- art for those who are working in this area and also for those who might exploit this new approach.

  18. A simple ear splint for microtia patients

    Directory of Open Access Journals (Sweden)

    C J Venkata Krishnan

    2015-01-01

    Full Text Available Microtia is a congenital anomaly of the ear can occur as an isolated birth defect or as part of a spectrum of anomalies or as a syndrome. Microtia is often associated with impaired hearing and or total loss of hearing. Such patients typically require treatment for surgical ear reconstruction and for hearing impairment. Maintenance of ear projection and post auricular sulcus in staged ear reconstruction in microtia is a trying problem. So also is the maintenance of the patency of the external auditory meatus following recanalization and meatoplasty.This case report describes a simple effective way of fabrication of ear splint prosthesis.

  19. A simple ear splint for microtia patients.

    Science.gov (United States)

    Krishnan, C J Venkata; Balaji, S M; Jain, Ashish R

    2015-01-01

    Microtia is a congenital anomaly of the ear can occur as an isolated birth defect or as part of a spectrum of anomalies or as a syndrome. Microtia is often associated with impaired hearing and or total loss of hearing. Such patients typically require treatment for surgical ear reconstruction and for hearing impairment. Maintenance of ear projection and post auricular sulcus in staged ear reconstruction in microtia is a trying problem. So also is the maintenance of the patency of the external auditory meatus following recanalization and meatoplasty.This case report describes a simple effective way of fabrication of ear splint prosthesis.

  20. Great Ears: Low-Frequency Sensitivity Correlates in Land and Marine Leviathans.

    Science.gov (United States)

    Ketten, D R; Arruda, J; Cramer, S; Yamato, M

    2016-01-01

    Like elephants, baleen whales produce low-frequency (LF) and even infrasonic (IF) signals, suggesting they may be particularly susceptible to underwater anthropogenic sound impacts. Analyses of computerized tomography scans and histologies of the ears in five baleen whale and two elephant species revealed that LF thresholds correlate with basilar membrane thickness/width and cochlear radii ratios. These factors are consistent with high-mass, low-stiffness membranes and broad spiral curvatures, suggesting that Mysticeti and Proboscidea evolved common inner ear adaptations over similar time scales for processing IF/LF sounds despite operating in different media.

  1. Technique for correction of lop ear.

    Science.gov (United States)

    Elsahy, N I

    1990-04-01

    Various techniques of correction of lop ear have been described. Minor lop ear deformity can easily be corrected with simple excision of the overhanging auricular cartilage. Moderate and severe lop ear deformities, on the other hand, are more difficult to correct because there is actual reduction in size of the upper third of the ear in addition to the overhanging auricular cartilage. The purpose of this paper was to present a new technique used to correct the moderate lop ear deformity. In addition to excising the overhanging cartilage, I rotate a cartilage flap from the anthelix upward where the missing superior crus was supposed to be. This flap increases the vertical height of the ear and creates a new superior crus. I applied this technique on three cases of moderate lop ear deformities with good results.

  2. Protection of horse ears against Simulid parasitism: Efficacy of a mammal semiochemical solution over 10hours.

    Science.gov (United States)

    Creton, Benjamin; Pageat, Patrick; Robejean, Myriam; Lafont-Lecuelle, Céline; Cozzi, Alessandro

    2016-08-30

    Hematophagous insects can be vectors of pathogens and cause significant economic loss in zootechnical production. Among biting insects, many dipteran species feed on horse blood. The black fly (Diptera: Simuliidae) group, is responsible for several disorders in horses and inflicts painful bites that lead to undesirable behaviours in horses, particularly when bites occur in sensitive areas such as the inner ear. A field study was conducted in a French equestrian center during which a semiochemical was applied on horses' ears to assess repellent efficacy against simulid infestation. During the first phase of the study, efficacy was evaluated over a one hour period. Then, during the second phase of the study, persistency of the effect was tested at 8, 9 and 10h after application. The results of the study's first phase showed 90% efficacy over one hour, with 121.5 insects found in control ears and 12 insects in treated ears (p=0.001). In the second phase of the study, a total amount of 411 insects were observed on control ears whereas only 2 insects were observed on treated ears (p<0.0001); the treatment remained over 98% effective up to 10hours after application. When using a slow release excipient, this semiochemical may offer at least 10h of protection against simulids. This safe, efficient, and long lasting protection could help horses and their owners to manage simulid parasitism. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. What middle ear parameters tell about impedance matching and high frequency hearing.

    Science.gov (United States)

    Hemilä, S; Nummela, S; Reuter, T

    1995-05-01

    Acoustic energy enters the mammalian cochlea aided by an anatomical impedance matching performed by the middle ear. The purpose of this paper is to analyse the functional consequences of changes in scale of the middle ear when going from the smallest mammals to the largest. Our anatomical measurements in mammals of different sizes ranging from bats to elephants indicate that middle ear proportions are largely isometric. Thus the calculated transformer ratio is basically independent of animal size, a typical value lying between 30 and 80. Similarly, the calculated specific acoustic input impedance of the inner ear is independent of animal size, the average value being about 140 kPa s/m. We show that if the high frequency hearing limit of isometric ears is limited by ossicle inertia, it should be inversely proportional to the cubic root of the ossicular mass. This prediction is in reasonable agreement with published audiogram data. We then present a three-parameter model of the middle ear where some obvious deviations from perfect isometry are taken into account. The high frequency hearing limits of different species generally agree well with the predictions of this simple model. However, the hearing limits of small rodents clearly deviate from the model calculation. We interpret this observation as indicating that the hearing limit towards very high frequencies may be set by cochlear transduction mechanisms. Further we discuss the exceptional high frequency hearing of the cat and the amphibious hearing of seals.

  4. Dominantly-inherited lop ears.

    Science.gov (United States)

    Leung, Alexander K C; Kong, Albert Y F; Robson, W Lane M; McLeod, D Ross

    2007-10-01

    We describe a four-generation Chinese family that included five members who had an isolated bilateral lop ear anomaly. The presentation suggested a dominant mode of inheritance. The absence of male-to-male transmission does not exclude an X-linked dominant mode of inheritance. Since the phenotypic anomaly of the male proband was no more severe than the affected female members, an autosomal dominant mode of inheritance is most likely. 2007 Wiley-Liss, Inc

  5. Causes of 279 Cases with Sensation of Ear Fullness%279例耳闷胀感的病因分析

    Institute of Scientific and Technical Information of China (English)

    陈平; 周永; 谭颂华; 唐安洲; 黄东红

    2001-01-01

    Objective To analyze the causes inducing the sensation of ear fullness.Methods 362 ears with sensation of ear fullness were collected.The clinic features,audiogram,tympanogram and Eustachian tube function in these ears were analysed.Results 203 ears with type A,111 ears with type B,33 ears with type C and 15 ears with perforated tympanum membrane were found in 362 ears as tympanograms were done.Among audiograms of 362 ears,conductive deafness,sensorineural deafness,mixed deafness and normal ears were 83、81、105 and 93 ears respectively.Eustachian tube test revealed 208 abnormal ears out of 362 ears,and 67 abnormal ears were found in 203 ears with type A tympanogram.Conclusion The causes inducing sensation of ear fullness covered the outer,middle and inner ear,and face nerve.In these cases with sensation of ear fullness,the diseases resulted in sensation of ear fullness mainly were secretory otitis media,sensorineural deafness induced by vary causes and abnormal eustachian tube function.%目的 探讨产生耳闷胀感的部位和原因。方法 收集耳闷胀感为主诉的279例362耳,对患耳的临床表现、鼓室导抗图、纯音测听和咽鼓管功能进行分析。结果 362耳中鼓室导抗图A型203耳、B型111耳、C型33耳以及鼓膜穿孔15耳。纯音测听表现为传导性聋、感音神经性聋、混合性聋以及正常者分别是83耳、81耳、105耳和93耳。在362耳中,咽鼓管功能异常208耳,在A型鼓室导抗图203耳中,咽鼓管功能异常67耳。结论 产生耳闷胀感的病变部位包括外、中、内耳和面神经的病变,其中以分泌性中耳炎、各种原因引起的感音神经性聋和“咽鼓管狭窄症”为多。

  6. Better late than never: effective air-borne hearing of toads delayed by late maturation of the tympanic middle ear structures.

    Science.gov (United States)

    Womack, Molly C; Christensen-Dalsgaard, Jakob; Hoke, Kim L

    2016-10-15

    Most vertebrates have evolved a tympanic middle ear that enables effective hearing of airborne sound on land. Although inner ears develop during the tadpole stages of toads, tympanic middle ear structures are not complete until months after metamorphosis, potentially limiting the sensitivity of post-metamorphic juveniles to sounds in their environment. We tested the hearing of five species of toads to determine how delayed ear development impairs airborne auditory sensitivity. We performed auditory brainstem recordings to test the hearing of the toads and used micro-computed tomography and histology to relate the development of ear structures to hearing ability. We found a large (14-27 dB) increase in hearing sensitivity from 900 to 2500 Hz over the course of ear development. Thickening of the tympanic annulus cartilage and full ossification of the middle ear bone are associated with increased hearing ability in the final stages of ear maturation. Thus, juvenile toads are at a hearing disadvantage, at least in the high-frequency range, throughout much of their development, because late-forming ear elements are critical to middle ear function at these frequencies. We discuss the potential fitness consequences of late hearing development, although research directly addressing selective pressures on hearing sensitivity across ontogeny is lacking. Given that most vertebrate sensory systems function very early in life, toad tympanic hearing may be a sensory development anomaly. © 2016. Published by The Company of Biologists Ltd.

  7. Anatomy of the lamprey ear: morphological evidence for occurrence of horizontal semicircular ducts in the labyrinth of Petromyzon marinus

    Science.gov (United States)

    Maklad, Adel; Reed, Caitlyn; Johnson, Nicholas S.; Fritzsch, Bernd

    2014-01-01

    In jawed (gnathostome) vertebrates, the inner ears have three semicircular canals arranged orthogonally in the three Cartesian planes: one horizontal (lateral) and two vertical canals. They function as detectors for angular acceleration in their respective planes. Living jawless craniates, cyclostomes (hagfish and lamprey) and their fossil records seemingly lack a lateral horizontal canal. The jawless vertebrate hagfish inner ear is described as a torus or doughnut, having one vertical canal, and the jawless vertebrate lamprey having two. These observations on the anatomy of the cyclostome (jawless vertebrate) inner ear have been unchallenged for over a century, and the question of how these jawless vertebrates perceive angular acceleration in the yaw (horizontal) planes has remained open. To provide an answer to this open question we reevaluated the anatomy of the inner ear in the lamprey, using stereoscopic dissection and scanning electron microscopy. The present study reveals a novel observation: the lamprey has two horizontal semicircular ducts in each labyrinth. Furthermore, the horizontal ducts in the lamprey, in contrast to those of jawed vertebrates, are located on the medial surface in the labyrinth rather than on the lateral surface. Our data on the lamprey horizontal duct suggest that the appearance of the horizontal canal characteristic of gnathostomes (lateral) and lampreys (medial) are mutually exclusive and indicate a parallel evolution of both systems, one in cyclostomes and one in gnathostome ancestors.

  8. Anatomy of the lamprey ear: morphological evidence for occurrence of horizontal semicircular ducts in the labyrinth of Petromyzon marinus.

    Science.gov (United States)

    Maklad, Adel; Reed, Caitlyn; Johnson, Nicolas S; Fritzsch, Bernd

    2014-04-01

    In jawed (gnathostome) vertebrates, the inner ears have three semicircular canals arranged orthogonally in the three Cartesian planes: one horizontal (lateral) and two vertical canals. They function as detectors for angular acceleration in their respective planes. Living jawless craniates, cyclostomes (hagfish and lamprey) and their fossil records seemingly lack a lateral horizontal canal. The jawless vertebrate hagfish inner ear is described as a torus or doughnut, having one vertical canal, and the jawless vertebrate lamprey having two. These observations on the anatomy of the cyclostome (jawless vertebrate) inner ear have been unchallenged for over a century, and the question of how these jawless vertebrates perceive angular acceleration in the yaw (horizontal) planes has remained open. To provide an answer to this open question we reevaluated the anatomy of the inner ear in the lamprey, using stereoscopic dissection and scanning electron microscopy. The present study reveals a novel observation: the lamprey has two horizontal semicircular ducts in each labyrinth. Furthermore, the horizontal ducts in the lamprey, in contrast to those of jawed vertebrates, are located on the medial surface in the labyrinth rather than on the lateral surface. Our data on the lamprey horizontal duct suggest that the appearance of the horizontal canal characteristic of gnathostomes (lateral) and lampreys (medial) are mutually exclusive and indicate a parallel evolution of both systems, one in cyclostomes and one in gnathostome ancestors.

  9. Differential Gene Expression in the Otic Capsule and the Middle Ear-An Annotation of Bone-Related Signaling Genes

    DEFF Research Database (Denmark)

    Nielsen, Michelle C.; Martin-Bertelsen, Tomas; Friis, Morten;

    2015-01-01

    and stria vascularis) and the lining tissues from the middle ear of the rat. Data was analyzed with statistical bioinformatics tools. Gene expression levels of selected genes were validated using quantitative polymerase chain reaction. Results: A total of 413 genes were identified when young inner bulla...

  10. The photogrammetric inner constraints

    Science.gov (United States)

    Dermanis, Athanasios

    A derivation of the complete inner constraints, which are required for obtaining "free network" solutions in close-range photogrammetry, is presented. The inner constraints are derived analytically for the bundle method, by exploiting the fact that the rows of their coefficient matrix from a basis for the null subspace of the design matrix used in the linearized observation equations. The derivation is independent of any particular choice of rotational parameters and examples are given for three types of rotation angles used in photogrammetry, as well as for the Rodriguez elements. A convenient algorithm based on the use of the S-transformation is presented, for the computation of free solutions with either inner or partial inner constraints. This approach is finally compared with alternative approaches to free network solutions.

  11. Inner Consciousness Tindakan Nabi

    Directory of Open Access Journals (Sweden)

    Moh. Helmi Umam

    2015-09-01

    Full Text Available The article is written to examine deeds and actions of the Prophet Muhammad (peace be upon him within inner consciousness analysis of Husserl’s phenomenology. The article is formulated to explore the significance of phenomenology of religious study, Prophet’s deeds as well as his inner consciousness, and inner consciousness analysis of Prophet’s deeds. This article is written using phenomenological method, i.e. a comprehensive interpretation about the source of information or object’s phenomenon as long as it can be traced. Inner consciousness of Prophet’s actions sees that his deeds in deciding important religious pronouncements were results of long-term memory based on divine and social argumentations, which have came into Prophet’s consciousness as a human.

  12. Optical assessment of middle ear inflammation

    OpenAIRE

    Jung, David S.

    2016-01-01

    This thesis describes the development of an optical device to assess the inflammatory state of the middle ear mucosa through the ear canal, after ventilation tube insertion in otitis media with effusion in children. An optical phantom of the middle ear was developed in order to allow repeatable experiments. The phantom consists of eardrum and mucosa while all other structures are neglected. The optical properties of the phantom were determined based on literature review and experiments on...

  13. Fechner's "inner psychophysics".

    Science.gov (United States)

    Robinson, David K

    2010-11-01

    Though psychologists are generally aware that Gustav Fechner introduced psychophysics and set down its essential methodology, most of them only know about the part that Fechner called "outer psychophysics." In his classic publication of 1860, Fechner insisted that "inner psychophysics" was more important, yet this aspect of Fechner's work failed to receive any attention. The article reviews Fechner's presentation of inner psychophysics and suggests reasons why that part of his work was neglected and has been forgotten.

  14. ATLAS inner detector performance

    CERN Document Server

    Gadomski, S

    2001-01-01

    The ATLAS Inner Detector consists of three subsystems using different tracking detector technologies: silicon pixels, silicon strips and straw tubes. The combination gives ATLAS a robust, hermetic and efficient tracking system, able to reconstruct tracks at the highest foreseen LHC luminosities. The inner detector provides vertex and momentum measurements, electron identification and some $K/\\pi$ separation. Since last year the beam pipe of ATLAS was changed, causing a redesign of the first tracking layer and a deterioration of the impact parameter resolutions.

  15. Autoimmune ear disease: clinical and diagnostic relevance in Cogan’s sydrome

    Directory of Open Access Journals (Sweden)

    Luigi Maiolino

    2017-03-01

    Full Text Available The autoimmune inner ear disease is a clinical syndrome with uncertain pathogenesis that is often associated to rapidly progressive hearing loss that, especially at the early stages of disease, may be at monoaural localization, although more often it is at binaural localization. It usually occurs as a sudden deafness, or a rapidly progressive sensorineural hearing loss. In this study a particular form of autoimmune inner ear disease is described, Cogan’s syndrome. Cogan’s syndrome is a chronic inflammatory disorder that most commonly affects young adults. Clinical hallmarks are interstitial keratitis, vestibular and auditory dysfunction. Associations between Cogan’s syndrome and systemic vasculitis, as well as aortitis, also exist. We report a case of a young woman who presented audiological and systemic characteristics attributable to Cogan’s syndrome. In the description of the case we illustrate how the appearance and evolution of the disease presented.

  16. Assessment of middle ear effusion and audiological characteristics in young children with adenoid hypertrophy

    Institute of Scientific and Technical Information of China (English)

    REN Dong-dong; WANG Wu-qing

    2012-01-01

    Background Otitis media with effusion is a highly concurrent disease in young children with adenoid hypertrophy.The aim of this study was to assess the middle ear effusion and audiological characteristics in children with adenoid hypertrophy and compare the various assessment methods.@@Methods Two hundred and seven candidates who were to undergo adenoidectomy were analyzed using otoscopy,tympanometry,air-conduction auditory steady-state responses (AC-ASSR),and computerized tomography (CT) before adenoidectomy.@@Results About 73.4% (304/414) of ears were confirmed to have middle ear effusion (MEE) by otoscopy; 75.4% (312/414) of ears revealed MEE by CT.CT scan correctly predicted all the myringotomy results,giving 100% accuracy on the diagnosis of MEE.Additionally,CT revealed two children with inner ear malformations.Type B tracing tympanogram provided a sensitivity of 91.7% and a specificity of 92.2%.Type C tympanogram with peak pressure <-200 daPa indicated effusion; type C tympanogram having acoustic stapedius reflex could exclude MEE.We excluded the AC-ASSR results of the 4 ears with malformation; 54.4% (223/410) of ears were confirmed of hearing loss.Furthermore,5.2%(16/310) of the ears with MEE suffered from severe to profound hearing loss.The average threshold level in the 0.25 kHz frequency of children was found to have poorer hearing thresholds than those in the 0.5,1,2,and 4 kHz (P <0.001) frequencies; 29.7% (92/310) of ears with MEE were regarded as normal hearing level.About 55.8% (173/310) of ears with MEE were classified as having slight-mild hearing loss.@@Conclusions The practitioners should pay much attention to the middle ear condition and be aware of a possible development of severe to profound hearing loss during the course of MEE in young children with adenoid hypertrophy.CT scan is good for the assessment of MEE before ventilation tube insertion.

  17. An Effective 3D Ear Acquisition System.

    Directory of Open Access Journals (Sweden)

    Yahui Liu

    Full Text Available The human ear is a new feature in biometrics that has several merits over the more common face, fingerprint and iris biometrics. It can be easily captured from a distance without a fully cooperative subject. Also, the ear has a relatively stable structure that does not change much with the age and facial expressions. In this paper, we present a novel method of 3D ear acquisition system by using triangulation imaging principle, and the experiment results show that this design is efficient and can be used for ear recognition.

  18. An Effective 3D Ear Acquisition System.

    Science.gov (United States)

    Liu, Yahui; Lu, Guangming; Zhang, David

    2015-01-01

    The human ear is a new feature in biometrics that has several merits over the more common face, fingerprint and iris biometrics. It can be easily captured from a distance without a fully cooperative subject. Also, the ear has a relatively stable structure that does not change much with the age and facial expressions. In this paper, we present a novel method of 3D ear acquisition system by using triangulation imaging principle, and the experiment results show that this design is efficient and can be used for ear recognition.

  19. Cochlear Implant Outcomes and Genetic Mutations in Children with Ear and Brain Anomalies

    OpenAIRE

    Micol Busi; Monica Rosignoli; Alessandro Castiglione; Federica Minazzi; Patrizia Trevisi; Claudia Aimoni; Ferdinando Calzolari; Enrico Granieri; Alessandro Martini

    2015-01-01

    Background. Specific clinical conditions could compromise cochlear implantation outcomes and drastically reduce the chance of an acceptable development of perceptual and linguistic capabilities. These conditions should certainly include the presence of inner ear malformations or brain abnormalities. The aims of this work were to study the diagnostic value of high resolution computed tomography (HRCT) and magnetic resonance imaging (MRI) in children with sensorineural hearing loss who were can...

  20. Numerical evaluation of implantable hearing devices using a finite element model of human ear considering viscoelastic properties.

    Science.gov (United States)

    Zhang, Jing; Tian, Jiabin; Ta, Na; Huang, Xinsheng; Rao, Zhushi

    2016-08-01

    Finite element method was employed in this study to analyze the change in performance of implantable hearing devices due to the consideration of soft tissues' viscoelasticity. An integrated finite element model of human ear including the external ear, middle ear and inner ear was first developed via reverse engineering and analyzed by acoustic-structure-fluid coupling. Viscoelastic properties of soft tissues in the middle ear were taken into consideration in this model. The model-derived dynamic responses including middle ear and cochlea functions showed a better agreement with experimental data at high frequencies above 3000 Hz than the Rayleigh-type damping. On this basis, a coupled finite element model consisting of the human ear and a piezoelectric actuator attached to the long process of incus was further constructed. Based on the electromechanical coupling analysis, equivalent sound pressure and power consumption of the actuator corresponding to viscoelasticity and Rayleigh damping were calculated using this model. The analytical results showed that the implant performance of the actuator evaluated using a finite element model considering viscoelastic properties gives a lower output above about 3 kHz than does Rayleigh damping model. Finite element model considering viscoelastic properties was more accurate to numerically evaluate implantable hearing devices.

  1. Middle ear impedance studies in elderly patients implications on age-related hearing loss

    Directory of Open Access Journals (Sweden)

    Olusola Ayodele Sogebi

    2015-04-01

    Full Text Available INTRODUCTION: Controversies arise with respect to functioning of the middle ear over time.OBJECTIVE: To assess changes in middle ear impedance that may be related to aging, and/or if there was an association of these changes with those of the inner ear in the elderly patients.METHODS: Cross-sectional, comparative study of elderly patients managed in ear, nose and throat clinics. A structured questionnaire was administered to obtain clinical information. Pure tone audiometry, tympanometry, and acoustic reflexes were performed. Comparative analyses were performed to detect intergroup differences between clinico-audiometric findings and middle ear measures, viz. tympanograms and acoustic reflexes.RESULTS: One hundred and three elderly patients participated in the study; 52.4% were male, averagely 70.0 ± 6.3 years old, age-related hearing loss in 59.2%, abnormal tympanograms in 39.3%, absent acoustic reflex in 37.9%. There was no association between age and gender in patients with abnormal tympanograms and absent acoustic reflex. Significantly more patients with different forms and grades of age-related hearing loss had abnormal tympanometry and absent acoustic reflex.CONCLUSION: Some abnormalities were observed in the impedance audiometric measures of elderly patients, which were significantly associated with parameters connected to age-related hearing loss.

  2. Playing by Ear: Foundation or Frill?

    Science.gov (United States)

    Woody, Robert H.

    2012-01-01

    Many people divide musicians into two types: those who can read music and those who play by ear. Formal music education tends to place great emphasis on producing musically literate performers but devotes much less attention to teaching students to make music without notation. Some would suggest that playing by ear is a specialized skill that is…

  3. Objective Audiometry using Ear-EEG

    DEFF Research Database (Denmark)

    Christensen, Christian Bech; Kidmose, Preben

    life. Ear-EEG may therefore be an enabling technology for objective audiometry out of the clinic, allowing regularly fitting of the hearing aids to be made by the users in their everyday life environment. In this study we investigate the application of ear-EEG in objective audiometry....

  4. Coupled ears in lizards and crocodilians

    DEFF Research Database (Denmark)

    Carr, Catherine E; Christensen-Dalsgaard, Jakob; Bierman, Hilary

    2016-01-01

    Lizard ears are coupled across the pharynx, and are very directional. In consequence all auditory responses should be directional, without a requirement for computation of sound source location. Crocodilian ears are connected through sinuses, and thus less tightly coupled. Coupling may improve...

  5. Automorphisms and Inner Automorphisms

    Directory of Open Access Journals (Sweden)

    Ameer Jaber

    2016-01-01

    Full Text Available Let K be a field of characteristic not 2 and let A=A0+A1 be central simple superalgebra over K, and let ⁎ be superinvolution on A. Our main purpose is to classify the group of automorphisms and inner automorphisms of (A,⁎ (i.e., commuting with ⁎ by using the classical theorem of Skolem-Noether. Also we study two examples of groups of automorphisms and inner automorphisms on even central simple superalgebras with superinvolutions.

  6. Microbiology of discharging ears in Ethiopia

    Institute of Scientific and Technical Information of China (English)

    Getachew Tesfaye; Daniel Asrat; Yimtubezinash Woldeamanuel; Messele Gizaw

    2009-01-01

    Objectives:To isolate and identify the bacterial etiologic agents,including their antibiotic susceptibility pat-tern isolated from patients with discharging ear infections.Methods:Between September 2006 and February 2007,178 patients with discharging ear visiting ENT clinics of St.Paul and Tikur Anbessa University Hospi-tals Addis Ababa,Ethiopia were investigated.Results:Of the patients investigated,52.8% were males and 47.2% were females resulting in an overall male to female ratio of 1.1:1.Ear discharge was the commonest clinical finding followed by hearing problem (91.2%),otalgia (ear pain)(74.7%),fever (17.9%)and itching of external ear (5.1%).S.aureus accounted for 30.2% of the total isolates followed by Proteus ssp. (P.mirabilis,P.vulgaris )(25.4%),and P.aeruginosa (13.4%).Both gram positive and negative bac-teria isolated from ear infections showed low resistance rates to most antimicrobial agents tested.Overall ceftri-axone and ciprofloxacin were the most effective drugs when compared to other drugs tested against the gram-positive and gram-negative bacteria.Conclusion:Otitis media was the most common clinical finding in pa-tients with ear infection.With discharging ear,the gram-negative bacteria were the predominant isolates.The susceptibility pattern of isolates from the study showed that ceftriaxone,ciprofloxacin and gentamicin were the most effective drugs.It is recommended that treatment of ear infections should be based on culture and sensi-tivity at the study sites.Therefore,efforts should be directed towards early diagnosis and treatment of acute ear infection and continued re-evaluation of the resistant patterns of organisms to optimize treatments and reduce complications.

  7. CT and MR imaging after middle ear surgery

    Energy Technology Data Exchange (ETDEWEB)

    Koesling, Sabrina E-mail: sabrina.koesling@medizin.uni-halle.de; Bootz, F

    2001-11-01

    This article describes the current value of imaging in patients after stapes surgery and surgery after chronic otitis media including cholesteatoma. Possibilities and limits of computed tomography (CT) and MRI are described and most important investigation parameters are mentioned. After otosclerosis surgery, CT is the method of first choice in detection of reasons for vertigo and/or recurrent hearing loss in the later postoperative phase. CT may show the position and condition of prosthesis, scarring around the prosthesis and otospongiotic foci. Sometimes, it gives indirect hints for perilymphatic fistulas and incus necrosis. MRI is able to document inner ear complications. CT has a high negative predictive value in cases with a free cavity after mastoidectomy. Localized opacities or total occlusion are difficult to distinguish by CT alone. MRI provides important additional information in the differentiation of cholesterol granuloma, cholesteatoma, effusion, granulation and scar tissue.

  8. Microbiomes of the normal middle ear and ears with chronic otitis media.

    Science.gov (United States)

    Minami, Shujiro B; Mutai, Hideki; Suzuki, Tomoko; Horii, Arata; Oishi, Naoki; Wasano, Koichiro; Katsura, Motoyasu; Tanaka, Fujinobu; Takiguchi, Tetsuya; Fujii, Masato; Kaga, Kimitaka

    2017-10-01

    The aim of this study was to profile and compare the middle ear microbiomes of human subjects with and without chronic otitis media. Prospective multicenter cohort study. All consecutive patients undergoing tympanoplasty surgery for chronic otitis media or ear surgery for conditions other than otitis media were recruited. Sterile swab samples were collected from the middle ear mucosa during surgery. The variable region 4 of the 16S rRNA gene in each sample were amplified using region-specific primers adapted for the Illumina MiSeq sequencer (Illumina, CA, USA)). The sequences were subjected to local blast and classified using Metagenome@KIN (World Fusion, Tokyo, Japan). In total, 155 participants were recruited from seven medical centers. Of these, 88 and 67 had chronic otitis media and normal middle ears, respectively. The most abundant bacterial phyla on the mucosal surfaces of the normal middle ears were Proteobacteria, followed by Actinobacteria, Firmicutes, and Bacteroidetes. The children and adults with normal middle ears differed significantly in terms of middle ear microbiomes. Subjects with chronic otitis media without active inflammation (dry ear) had similar middle ear microbiomes as the normal middle ears group. Subjects with chronic otitis media with active inflammation (wet ear) had a lower prevalence of Proteobacteria and a higher prevalence of Firmicutes than the normal middle ears. The human middle ear is inhabited by more diverse microbial communities than was previously thought. Alteration of the middle ear microbiome may contribute to the pathogenesis of chronic otitis media with active inflammation. 2b. Laryngoscope, 127:E371-E377, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

  9. Osteomas of the middle ear

    Directory of Open Access Journals (Sweden)

    Sente Marko

    2004-01-01

    Full Text Available INTRODUCTION Osteomas of the middle ear are small, single, usually unilateral, peduncular growths, off-white in color, with smooth or multilobular surface, asymptomatic or causing functional disorders (progressive hearing loss, pathological appearance of the eardrum, vertigo and otorrhea, of unclear or unknown etiology. Fleury described three types of osteomas: massive, diffuse atticoantral and localized type. The therapy is surgical. Small and asymptomatic ones are followed-up. Cremers suggests surgical intervention in cases of progressive growth and increased hearing loss. Case description Discharge and pain in the left ear started twelve years ago, accompanied by impaired hearing and tinnitus. Four months ago the symptoms aggravated and discharge and pain increased. Otomicroscopic findings revealed: perforation in the posterior attic and a prominent polypous, clustered bright red formation. Schüller X-ray showed total absence of pneumocyte cells, with distinct sclerotic changes. Retroauricular access showed a biventricular bony formation in the cavum and partly in the antrum. A cholesteatoma extended from the cavum into the antrum, above the osteatoma. The bony formation was separated transmeatally from the grip in the posterior attic using a chisel, partially removing the bone wall of the exterior aural tube, removing it completely through the mastoid antrum. The removed bony mass, sized 5 x 8 x 8 mm, included also the incus. DISCUSSION Osteoma was discovered accidentally. Regarding clinical features, it belonged to the second group, due to progressive hearing loss, recurrent episodes of otorrhea, pain, biventricular shape and association with cholesteatoma. It was removed using a combined method. It was not possible to establish when the osteoma exactly started generating. It is possible that the initial complaints twelve years ago were the first signs of illness, and chronic otitis may have occurred as a consequence of the tumor.

  10. The Inner Voice

    Science.gov (United States)

    Ridgway, Anthony James

    2009-01-01

    The inner voice- we all know what it is because we all have it and use it when we are thinking or reading, for example. Little work has been done on it in our field, with the notable exception of Brian Tomlinson, but presumably it must be a cognitive phenomenon which is of great importance in thinking, language learning, and reading in a foreign…

  11. Core collapse supernova remnants with ears

    CERN Document Server

    Grichener, Aldana

    2016-01-01

    We study the morphologies of core collapse supernova remnants (CCSNRs) and find that about third of CCSNRs have two opposite `ears' protruding from their main shell, and that the typical energy that is required to inflate these ears is about 10 percents of the explosion kinetic energy. We argue that these properties are most compatible with the expectation from the explosion jet feedback mechanism (JFM). Based on previous studies of ears in CCSNRs and the similarity of some ears to those found in planetary nebulae, we assume that the ears are inflated by jets that are launched during the explosion, or a short time after it. In the JFM explosion process the last jets' launching episode takes place just after the core has been ejected. These jets expand freely, interact with the exploding gas at some distance from the center, and form the ears. Under simple geometrical assumptions we find that the extra kinetic energy of the ears is in the range of 1 to 10 percents of the explosion energy. As not all of the kin...

  12. Imaging of the postoperative middle ear

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Marc T. [Department of Medical Imaging, Fondation Ophtalmologique Adolphe de Rothschild, 25 rue Manin, 75940, Paris (France); Ayache, Denis [Department of Otorhinolaryngology, Fondation Ophtalmologique Adolphe de Rothschild, Paris (France)

    2004-03-01

    The aim of this article is twofold: (a) to present the principles and the indications of surgical treatment of middle ear pathologies; and (b) to review the imaging findings after middle ear surgery, including the normal postoperative aspects and imaging findings in patients presenting with unsatisfactory surgical results or with suspicion of postoperative complications. This review is intentionally restricted to the most common diseases involving the middle ear: chronic otitis media and otosclerosis. In these specific fields of interest, CT and MR imaging play a very important role in the postoperative follow-up and in the work-up of surgical failures and complications. (orig.)

  13. [Ear keloid and clinical research progress].

    Science.gov (United States)

    Du, Guangyuan; Zhu, Jiang

    2014-04-01

    Keloid refers to the damaged skin due to excessive fibroblast proliferation. Ear is one predilection site. The pathogenesis of ear keloid is not very clear, and the treatment is also varied. Surgery, postoperative radiotherapy and laser treatment, steroid hormones, pressure therapy are the basic treatment methods. Integrated application of a variety of treatments, classification research and new materials using revealed the prospect for the treatment of the disease. This thesis reviews literature about ear keloid in recent 10 years, and introduces this disease and clinical research progress.

  14. Surgical Management of Ear Diseases in Rabbits.

    Science.gov (United States)

    Csomos, Rebecca; Bosscher, Georgia; Mans, Christoph; Hardie, Robert

    2016-01-01

    Otitis externa and media are frequently diagnosed disorders in rabbits and are particularly common in lop-eared breeds because of the specific anatomy of the ear canal. Medical management for otitis externa and media often provides only a temporary improvement in clinical signs. Surgery by means of partial or total ear canal ablation (PECA or TECA) combined with lateral bulla osteotomy (LBO) represents a feasible approach that is well tolerated and provides a good clinical outcome. Short-term complications associated with PECA/TECA-LBO include facial nerve paralysis and vestibular disease.

  15. Injuries of the external ear.

    Science.gov (United States)

    Templer, J; Renner, G J

    1990-10-01

    Ear injuries occur in people of all ages but predominate in active people such as wrestlers, boxers, and bike riders. The types and extent of injury are a function of the force causing the injury. Shearing forces of moderate intensity cause hematoma formation, whereas greater force causes lacerations or even amputation. Sharp objects cause lacerations determined by the force, direction, and point of impact. The high ratio of surface area to mass makes the auricle vulnerable to extremes of temperature. People participating in high-risk activities should wear protective headgear. The goal of treatment is to restore the normal contours while preventing infection. Hematoma results in disfigurement by organization or chondritis. Evacuation and pressure dressings using sterile technique correct the condition. Second-degree burns are treated by regular cleansing and application of topical antimicrobials. Deeper burns require debridement, biologic dressings, or burying the cartilage subcutaneously for later reconstruction. Simple lacerations are closed under aseptic technique using either skin-to-skin sutures only or sutures of the skin combined with intercartilage sutures. Extensive and complex lacerations require meticulous care to match all fragments and prevent infection or loss of tissue. Bare cartilage must be covered with vascularized tissue. The treatment of total amputation is controversial. Some advocate reattachment as a composite graft using intravenous low molecular weight dextrans and heparin as adjuvants. Mladick dermabrades the amputated pinna, reattaches it with sutures, and then slips it into a pocket of elevated postauricular skin for 2 weeks. Others urge microvascular reanastomosis of the small nutrient vessels. Brent and Byrd separate the cartilage from its overlying skin and envelope it first with vascularized temporoparietal fascia and then a split-thickness skin graft. Chondritis is the most feared complication of injury or surgery of the pinna. It

  16. Ear manipulations reveal a critical period for survival and dendritic development at the single-cell level in Mauthner neurons.

    Science.gov (United States)

    Elliott, Karen L; Houston, Douglas W; DeCook, Rhonda; Fritzsch, Bernd

    2015-12-01

    Second-order sensory neurons are dependent on afferents from the sense organs during a critical period in development for their survival and differentiation. Past research has mostly focused on whole populations of neurons, hampering progress in understanding the mechanisms underlying these critical phases. To move toward a better understanding of the molecular and cellular basis of afferent-dependent neuronal development, we developed a new model to study the effects of ear removal on a single identifiable cell in the hindbrain of a frog, the Mauthner cell. Ear extirpation at various stages of Xenopus laevis development defines a critical period of progressively-reduced dependency of Mauthner cell survival/differentiation on the ear afferents. Furthermore, ear removal results in a progressively decreased reduction in the number of dendritic branches. Conversely, addition of an ear results in an increase in the number of dendritic branches. These results suggest that the duration of innervation and the number of inner ear afferents play a quantitative role in Mauthner cell survival/differentiation, including dendritic development.

  17. Earth's inner core: Innermost inner core or hemispherical variations?

    NARCIS (Netherlands)

    Lythgoe, K. H.; Deuss, A.; Rudge, J. F.; Neufeld, J. A.

    2014-01-01

    The structure of Earth's deep inner core has important implications for core evolution, since it is thought to be related to the early stages of core formation. Previous studies have suggested that there exists an innermost inner core with distinct anisotropy relative to the rest of the inner core.

  18. Earth's inner core: Innermost inner core or hemispherical variations?

    NARCIS (Netherlands)

    Lythgoe, K. H.; Deuss, A.; Rudge, J. F.; Neufeld, J. A.

    2014-01-01

    The structure of Earth's deep inner core has important implications for core evolution, since it is thought to be related to the early stages of core formation. Previous studies have suggested that there exists an innermost inner core with distinct anisotropy relative to the rest of the inner core.

  19. Ear Infection Treatment: Do Alternative Therapies Work?

    Science.gov (United States)

    ... in books and magazines. They include chiropractic adjustments, homeopathy, herbal eardrops and others. Perhaps you're seeking ... infection treatments have been studied with mixed results. Homeopathy. A controversial treatment for ear infection, homeopathy involves ...

  20. Superglue accidentally used as ear drops

    National Research Council Canada - National Science Library

    Anusha, Bala; Purushotman, R; Lina, L C; Avatar, S

    2012-01-01

    Superglue in the ear as a foreign body is an uncommon presentation. We report the case of a lady who accidentally instilled superglue directly onto her tympanic membrane and presented five days later...