Fibrous Dysplasia of the Temporal Bone with External Auditory Canal Stenosis and Secondary Cholesteatoma.

PubMed

Liu, Yu-Hsi; Chang, Kuo-Ping

2016-04-01

Fibrous dysplasia is a slowly progressive benign fibro-osseous disease, rarely occurring in temporal bones. In these cases, most bony lesions developed from the bony part of the external auditory canals, causing otalgia, hearing impairment, otorrhea, and ear hygiene blockade and probably leading to secondary cholesteatoma. We presented the medical history of a 24-year-old woman with temporal monostotic fibrous dysplasia with secondary cholesteatoma. The initial presentation was unilateral conductive hearing loss. A hard external canal tumor contributing to canal stenosis and a near-absent tympanic membrane were found. Canaloplasty and type I tympanoplasty were performed, but the symptoms recurred after 5 years. She received canal wall down tympanomastoidectomy with ossciculoplasty at the second time, and secondary cholesteatoma in the middle ear was diagnosed. Fifteen years later, left otorrhea recurred again and transcanal endoscopic surgery was performed for middle ear clearance. Currently, revision surgeries provide a stable auditory condition, but her monostotic temporal fibrous dysplasia is still in place.

Inverted u-shaped purse and rotation flaps: correcting the inferoposterior deformity of reconstructed ears after canaloplasty of the external auditory meatus.

PubMed

Ji, Chenyang; Zhang, Jinming; An, Geng; Liang, Weiqiang; Pan, Shujuan; Chen, Yuhong; Wei, Zhe; Zhang, Ganlin

2012-06-01

After patients with congenital microtia receive external ear canal plasty, the mastoid area usually has insufficient space for ear reconstruction. Hence, after ear reconstruction, an inferoposterior position deformity of the ear appears to some extent. Using inverted U-shaped purse and rotation flaps can correct this deformity effectively. From May of 2009 to September of 2011, five patients received the described procedures in the authors' department. Inverted U-shaped purse and rotation flaps were used for all the patients. The inverted U-shaped purse flap was used to reduce the area of the canal orifice and to lower the position, and the rotation flap was applied to turn the ear in a more superoposterior position. Two patients also received full-thickness skin grafting to cover the secondary wound. In four patients, V-Y-plasty or Z-plasty was used to adjust the flap transition. For the five patients, the distances between the ear antihelix and canal orifice were shortened, and the areas of the canal orifice were diminished. The retroversion of the auricle was corrected in various degrees, and the angles of the long axis of the auricle and the horizontal line were increased an average of 14.4°. The vertical distance between the top of the helix and the center of the canal orifice was increased an average of 15.2 mm. A slight dog ear deformity in front of the crus of the helix was left after the operation, but it was alleviated in the follow-up period. By using inverted U-shaped purse and rotation flaps, the inferoposterior position deformity of the reconstructed ear after external ear canal plasty in congenital microtia can be resolved effectively. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors http://www.springer.com/00266.

Challenges in fitting a hearing aid to a severely collapsed ear canal and mixed hearing loss.

PubMed

Oeding, Kristi; Valente, Michael; Chole, Richard

2012-04-01

Collapsed ear canals typically occur when an outside force, such as a headset for audiometric testing, is present. However, when a collapsed ear canal occurs without external pressure, this creates a challenge not only for performing audiometric testing but also for coupling a hearing aid to the ear canal. This case report highlights the challenges associated with fitting a hearing aid on a patient with a severe anterior-posterior collapsed ear canal with a mixed hearing loss. A 67-yr-old female originally presented to Washington University in St. Louis School of Medicine in 1996 with a long-standing history of bilateral otosclerosis. She had chronic ear infections in the right ear and a severely collapsed ear canal in the left ear and was fit with a bone anchored hearing aid (BAHA®) on the right side in 2003. However, benefit from the BAHA started to decrease due to changes in hearing, and a different hearing solution was needed. It was proposed that a hearing aid be fit to her collapsed left ear canal; however, trying to couple a hearing aid to the collapsed ear canal required unique noncustom earmold solutions. This case study highlights some of the obstacles and potential solutions for coupling a hearing aid to a severely collapsed ear canal. American Academy of Audiology.

Ewing Sarcoma of the External Ear Canal

PubMed Central

Kecelioglu Binnetoglu, Kiymet; Gerin, Fatma; Sari, Murat

2016-01-01

Background. Ewing sarcoma (ES) is a high-grade malignant tumor that has skeletal and extraskeletal forms and consists of small round cells. In the head and neck region, reported localization of extraskeletal ES includes the larynx, thyroid gland, submandibular gland, nasal fossa, pharynx, skin, and parotid gland, but not the external ear canal. Methods. We present the unique case of a 2-year-old boy with extraskeletal ES arising from the external ear canal, mimicking auricular hematoma. Results. Surgery was performed and a VAC/IE (vincristine, adriamycin, cyclophosphamide alternating with ifosfamide, and etoposide) regimen was used for adjuvant chemotherapy for 12 months. Conclusion. The clinician should consider extraskeletal ES when diagnosing tumors localized in the head and neck region because it may be manifested by a nonspecific clinical picture mimicking common otorhinolaryngologic disorders. PMID:27313930

Anatomical study of the pigs temporal bone by microdissection.

PubMed

Garcia, Leandro de Borborema; Andrade, José Santos Cruz de; Testa, José Ricardo Gurgel

2014-01-01

Initial study of the pig`s temporal bone anatomy in order to enable a new experimental model in ear surgery. Dissection of five temporal bones of Sus scrofa pigs obtained from UNIFESP - Surgical Skills Laboratory, removed with hole saw to avoid any injury and stored in formaldehyde 10% for better conservation. The microdissection in all five temporal bone had the following steps: inspection of the outer part, external canal and tympanic membrane microscopy, mastoidectomy, removal of external ear canal and tympanic membrane, inspection of ossicular chain and middle ear. Anatomically it is located at the same position than in humans. Some landmarks usually found in humans are missing. The tympanic membrane of the pig showed to be very similar to the human, separating the external and the middle ear. The middle ear`s appearance is very similar than in humans. The ossicular chain is almost exactly the same, as well as the facial nerve, showing the same relationship with the lateral semicircular canal. The temporal bone of the pigs can be used as an alternative for training in ear surgery, especially due the facility to find it and its similarity with temporal bone of the humans.

Klippel-Feil syndrome and associated ear anomalies.

PubMed

Yildirim, Nadir; Arslanoğlu, Atilla; Mahiroğullari, Mahir; Sahan, Murat; Ozkan, Hüseyin

2008-01-01

Klippel-Feil syndrome (KFS) is a congenital segmentation anomaly of the cervical vertebrae that manifests as short neck, low hair line, and limited neck mobility. Various systemic malformations may also accompany the syndrome including wide variety of otopathologies affecting all 3 compartments of the ear (external, middle, and inner ear) as well as internal acoustic canal and vestibular aqueduct. We aimed to investigate these involvements and their clinical correlates in a group of patients with KFS. We present 20 KFS cases, of which 12 (% 60) displayed most of the reported ear abnormalities such as microtia, external ear canal stenosis, chronic ear inflammations and their sequels, anomalies of the tympanic cavity and ossicles, inner ear dysplasies, deformed internal acoustic canal, and wide vestibular aqueduct, which are demonstrated using the methods of otoscopy, audiologic testing, and temporal bone computed tomography. This series represents one of the highest reported rate of ear involvement in KFS. We found no correlation between the identified ear pathologies and the skeletal and extraskeletal malformations. The genetic nature of the syndrome was supported by the existence of affected family members in 4 (20%) of the cases.

Bilateral acquired external auditory canal stenosis with squamous papilloma: a case report.

PubMed

Demirbaş, Duygu; Dağlı, Muharrem; Göçer, Celil

2011-01-01

Acquired external auditory canal (EAC) stenosis is described as resulting from a number of different causes such as infection, trauma, neoplasia, inflammation and radiotherapy. Human papilloma virus (HPV) type 6, a deoxyribonucleic acid (DNA) virus, is considered to cause squamous papilloma of the EAC. In this article, we report a case of a 56-year-old male with warty lesions in the left external ear and a totally stenotic right external ear which had similar lesions one year before the involvement of his left ear. On computed tomography of the temporal bone, there was soft tissue obstruction of the right EAC, and thickening in the skin of the left EAC. The middle ear structures were normal on both sides. Biopsy was performed from the lesion in the left ear, and revealed squamous papilloma. We presented this case because squamous papilloma related bilateral acquired EAC stenosis is a rare entity.

External Otitis (Swimmer's Ear)

MedlinePlus

... Debris removal, antibiotic ear drops, keeping water and cotton swabs out of the ear, and pain relievers ... Injuring the ear canal while cleaning it (using cotton swabs) or getting water or irritants, such as ...

Unusual extension of the first branchial cleft anomaly.

PubMed

Ada, Mehmet; Korkut, Nazim; Güvenç, M Güven; Acioğlu, Engin; Yilmaz, Süleyman; Cevikbaş, Uğur

2006-03-01

First branchial cleft is the only branchial structure that persists as the external ear canal, while all other clefts are resorbed. Incomplete obliteration and the degree of closure cause the varied types of first branchial cleft anomalies. They were classified based on the anatomical and histological features. We present an unusual type of first branchial cleft anomaly involving the external auditory canal, the middle ear and the nasopharynx through the eustachian tube.

Inner ear dysplasia is common in children with Down syndrome (trisomy 21).

PubMed

Blaser, Susan; Propst, Evan J; Martin, Daniel; Feigenbaum, Annette; James, Adrian L; Shannon, Patrick; Papsin, Blake C

2006-12-01

Middle and external ear anomalies are well recognized in Down syndrome (DS, trisomy 21). Inner ear anomalies are much less frequently described. This study reviews inner ear morphology on imaging to determine the prevalence of cochlear and vestibular anomalies in children with DS. The authors conducted a retrospective review of imaging features of (DS) inner ear structures. Fifty-nine sequential patients with DS with imaging of the inner ear were identified by a radiology report text search program. Quantitative biometric assessment of the inner ear was performed on patients with high-resolution computed tomography or magnetic resonance images of the petrous bone. Petrous imaging was performed for evaluation of inflammatory disease or hearing loss. Spinal imaging, which included petrous views, was performed in most cases to exclude C1 to 2 dislocation, a potential complication of DS. Measurements were compared with normative data. Inner ear dysplasia is much more common in DS than previously reported. Inner ear structures are universally hypoplastic. Vestibular malformations are particularly common and a small bony island of the lateral semicircular canal (<3 mm in diameter) appears highly typical. Additional findings in some patients were persistent lateral semicircular anlage with fusion of the lateral semicircular canal and vestibule into a single cavity, vestibular aqueduct and endolymphatic sac fossa enlargement, cochlear nerve canal hypoplasia, and stenosis or duplication of the internal auditory canal. Stenosis of the external meatus, poor mastoid pneumatization, middle ear and mastoid opacification, and cholesteatoma were common, as expected.

Occurrence and distribution of Malassezia species on skin and external ear canal of horses.

PubMed

Shokri, Hojjatollah

2016-01-01

The aim of this study was to investigate the prevalence of Malassezia species from the body skin and external ear canal of healthy horses. The samples were obtained by scraping the skin surface from the nose, groin and dorsum and swabbing from the external ear canal of 163 animals, and then incubated on sabouraud dextrose agar and modified Dixon agar. Malassezia species were isolated from 34.9% of horses. The percentages of Malassezia species were 64.3% for Arab, 35.7% for Persian, 35.4% for Thoroughbred and 27.1% for Turkmen breeds. The greatest abundance of Malassezia species was found in the external ear canal (47.7%, representing significant difference with other sites), followed by nose (26.3%), groin (15.8%) and dorsum (10.5%) (P < 0.05). A total of 57 strains from six Malassezia species were detected with a frequency rate as follows: M. pachydermatis (33.3%), M. globosa (26.3%), M. sympodialis (14.1%), M. restricta (10.5%), M. obtusa (8.8%) and M. furfur (7%). The most common age-group affected was 1-3 years (59.4%). This study confirmed that cutaneous Malassezia microbiota in healthy horses varies by body site and age but not by breed and gender, representing M. pachydermatis as the most prevalent species on horse skin. © 2015 Blackwell Verlag GmbH.

New HRCT-based measurement of the human outer ear canal as a basis for acoustical methods.

PubMed

Grewe, Johanna; Thiele, Cornelia; Mojallal, Hamidreza; Raab, Peter; Sankowsky-Rothe, Tobias; Lenarz, Thomas; Blau, Matthias; Teschner, Magnus

2013-06-01

As the form and size of the external auditory canal determine its transmitting function and hence the sound pressure in front of the eardrum, it is important to understand its anatomy in order to develop, optimize, and compare acoustical methods. High-resolution computed tomography (HRCT) data were measured retrospectively for 100 patients who had received a cochlear implant. In order to visualize the anatomy of the auditory canal, its length, radius, and the angle at which it runs were determined for the patients’ right and left ears. The canal’s volume was calculated, and a radius function was created. The determined length of the auditory canal averaged 23.6 mm for the right ear and 23.5 mm for the left ear. The calculated auditory canal volume (Vtotal) was 0.7 ml for the right ear and 0.69 ml for the left ear. The auditory canal was found to be significantly longer in men than in women, and the volume greater. The values obtained can be employed to develop a method that represents the shape of the auditory canal as accurately as possible to allow the best possible outcomes for hearing aid fitting.

A new skin flap method for total auricular reconstruction in microtia patients with a reconstructed ear canal: extended scalp and extended mastoid postauricular skin flaps.

PubMed

Hwang, Euna; Kim, Young Soo; Chung, Seum

2014-06-01

Before visiting a plastic surgeon, some microtia patients may undergo canaloplasty for hearing improvement. In such cases, scarred tissues and the reconstructed external auditory canal in the postauricular area may cause a significant limitation in using the posterior auricular skin flap for ear reconstruction. In this article, we present a new method for auricular reconstruction in microtia patients with previous canaloplasty. By dividing a postauricular skin flap into an upper scalp extended skin flap and a lower mastoid extended skin flap at the level of a reconstructed external auditory canal, the entire anterior surface of the auricular framework can be covered with the two extended postauricular skin flaps. The reconstructed ear shows good color match and texture, with the entire anterior surface of the reconstructed ear being resurfaced with the skin flaps. Clinical question/level of evidence; therapeutic level IV. Copyright © 2014 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

The effects of alterations in the osseous external auditory canal on perceived sound quality.

PubMed

van Spronsen, Erik; Brienesse, Patrick; Ebbens, Fenna A; Waterval, Jerome J; Dreschler, Wouter A

2015-10-01

To evaluate the perceptual effect of the altered shape of the osseous external auditory canal (OEAC) on sound quality. Prospective study. Twenty subjects with normal hearing were presented with six simulated sound conditions representing the acoustic properties of six different ear canals (three normal ears and three cavities). The six different real ear unaided responses of these ear canals were used to filter Dutch sentences, resulting in six simulated sound conditions. A seventh unfiltered reference condition was used for comparison. Sound quality was evaluated using paired comparison ratings and a visual analog scale (VAS). Significant differences in sound quality were found between the normal and cavity conditions (all P < .001) using both the seven-point paired comparison rating and the VAS. No significant differences were found between the reference and normal conditions. Sound quality deteriorates when the OEAC is altered into a cavity. This proof of concept study shows that the altered acoustic quality of the OEAC after radical cavity surgery may lead to a clearly perceived deterioration in sound quality. Nevertheless, some questions remain about the extent to which these changes are affected by habituation and by other changes in middle ear anatomy and functionality. 4 © 2015 The American Laryngological, Rhinological and Otological Society, Inc.

Air and Bone Conduction Frequency-specific Auditory Brainstem Response in Children with Agenesis of the External Auditory Canal

PubMed Central

Sleifer, Pricila; Didoné, Dayane Domeneghini; Keppeler, Ísis Bicca; Bueno, Claudine Devicari; Riesgo, Rudimar dos Santos

2017-01-01

Introduction  The tone-evoked auditory brainstem responses (tone-ABR) enable the differential diagnosis in the evaluation of children until 12 months of age, including those with external and/or middle ear malformations. The use of auditory stimuli with frequency specificity by air and bone conduction allows characterization of hearing profile. Objective  The objective of our study was to compare the results obtained in tone-ABR by air and bone conduction in children until 12 months, with agenesis of the external auditory canal. Method  The study was cross-sectional, observational, individual, and contemporary. We conducted the research with tone-ABR by air and bone conduction in the frequencies of 500 Hz and 2000 Hz in 32 children, 23 boys, from one to 12 months old, with agenesis of the external auditory canal. Results  The tone-ABR thresholds were significantly elevated for air conduction in the frequencies of 500 Hz and 2000 Hz, while the thresholds of bone conduction had normal values in both ears. We found no statistically significant difference between genders and ears for most of the comparisons. Conclusion  The thresholds obtained by bone conduction did not alter the thresholds in children with conductive hearing loss. However, the conductive hearing loss alter all thresholds by air conduction. The tone-ABR by bone conduction is an important tool for assessing cochlear integrity in children with agenesis of the external auditory canal under 12 months. PMID:29018492

Infantile inflammatory pseudotumor of the facial nerve as a complication of epidermal nevus syndrome with cholesteatoma.

PubMed

Hato, Naohito; Tsujimura, Mika; Takagi, Taro; Okada, Masahiro; Gyo, Kiyofumi; Tohyama, Mikiko; Tauchi, Hisamichi

2013-12-01

The first reported case of facial paralysis due to an inflammatory pseudotumor (IPT) of the facial nerve as a complication of epidermal nevus syndrome (ENS) is herein presented. A 10-month-old female patient was diagnosed with ENS at 3 months of age. She was referred to us because of moderate left facial paralysis. Epidermal nevi of her left auricle extended deep into the external ear canal. Otoscopy revealed polypous nevi and cholesteatoma debris filling the left ear. Computed tomography showed a soft mass filling the ear canal, including the middle ear, and an enormously enlarged facial nerve. Surgical exploration revealed numerous polypous nevi, external ear cholesteatoma, and tumorous swelling of the facial nerve. The middle ear ossicles were completely lost. The facial paralysis was improved after decompression surgery, but recurred 5 months later. A second operation was conducted 10 months after the first. During this operation, facial nerve decompression was completed from the geniculate ganglion to near the stylomastoid foramen. Histological diagnosis of the facial nerve tumor was IPT probably caused by chronic external ear inflammation induced by epidermal nevi. The facial paralysis gradually improved to House-Blackmann grade III 5 years after the second operation. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

[Antimycotic therapy in otomycosis with tympanic membrane perforation].

PubMed

Dyckhoff, G; Hoppe-Tichy, T; Kappe, R; Dietz, A

2000-01-01

Especially after prolonged antibiotic ototopic therapy otomycosis is not rare. An inoculation of fungi into the tympanic cavity however may have serious sequelae. Therefore an eradication of fungi from the external auditory canal is imperative before surgery. In addition to thorough cleaning of the outer ear canal antimycotic preparations are recommended in treating otomycosis. However, all of the commercially available ear drops contain ototoxic agents. In the case of defects of the tympanic membrane a damage of the inner ear may result. Alternatively, we suggest an aqueous solution of Miconazol 0,5%.

A practical use of a 16-gauge peripheral angiocatheter as an aspiration cautery in endoscopic ear surgery.

PubMed

Ozdek, Ali; Keseroglu, Kemal

2014-08-01

To define a technique for the practical use of a 16-gauge peripheral venous catheter as an insulated aspiration cautery in endoscopic ear surgery. Retrospective case review. Tertiary referral center. A 16-gauge intravenous catheter was prepared as a cauterization instrument with aspiration. After simple rearrangement of the exterior plastic portion, it was connected to a suction system. With the help of an unipolar cautery, aspiration of the blood and homeostasis was achieved. Hemorrhage of the external ear canal skin after incision can be easily coagulated with this instrument. During follow-up, there were no wound infection, facial nerve paresis, scar formation, and inadvertent burn of the external canal and auricular skin. With the help of this instrument, bleeding control during incision can be easily maintained. It is a simple, easily prepared, and alternative homeostasis technique in endoscopic ear surgery.

Computational Modeling of Blast Wave Transmission Through Human Ear.

PubMed

Leckness, Kegan; Nakmali, Don; Gan, Rong Z

2018-03-01

Hearing loss has become the most common disability among veterans. Understanding how blast waves propagate through the human ear is a necessary step in the development of effective hearing protection devices (HPDs). This article presents the first 3D finite element (FE) model of the human ear to simulate blast wave transmission through the ear. The 3D FE model of the human ear consisting of the ear canal, tympanic membrane, ossicular chain, and middle ear cavity was imported into ANSYS Workbench for coupled fluid-structure interaction analysis in the time domain. Blast pressure waveforms recorded external to the ear in human cadaver temporal bone tests were applied at the entrance of the ear canal in the model. The pressure waveforms near the tympanic membrane (TM) in the canal (P1) and behind the TM in the middle ear cavity (P2) were calculated. The model-predicted results were then compared with measured P1 and P2 waveforms recorded in human cadaver ears during blast tests. Results show that the model-derived P1 waveforms were in an agreement with the experimentally recorded waveforms with statistic Kurtosis analysis. The FE model will be used for the evaluation of HPDs in future studies.

Transcanal endoscopic resection for leiomyoma of the external auditory canal and a review of the literature.

PubMed

Ikeda, Ryoukichi; Tateda, Masaru; Okoshi, Akira; Morita, Shinkichi; Suzuki, Hiroyoshi; Hashimoto, Sho

2016-02-01

Leiomyoma usually originates from the uterus and alimentary tract, but in extremely rare cases leiomyoma can appear in the external auditory canal. Here we present a 37-year-old man with right auricular fullness. Preoperative findings suggested benign tumor or cholesteatoma in the right external auditory canal. We performed total resection using an endoauricular approach with transcanal endoscopic ear surgery. Histopathological and immunohistochemistry examination confirmed the diagnosis of leiomyoma of external auditory canal. Leiomyoma arising from soft tissue, including that in the external auditory canal, is classified into two types: that from the arrectores pilorum muscles and that from the muscle coats of blood vessels. Only four cases of leiomyoma of external auditor canal have been published in the English literature. The other four cases demonstrated vascular leiomyomas. This is the first report of leiomyoma of the EAC arising from arrectores pilorum muscles. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

21 CFR 344.3 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Definitions. 344.3 Section 344.3 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE... impairment. (d) Ear drying aid. A drug used in the external ear canal to help dry water-clogged ears. [51 FR...

Optical-fiber-coupled inferometric measurement of tympanic membrane temperature: a new diagnostic tool for acute otitis media

NASA Astrophysics Data System (ADS)

DeRowe, Ari; Ophir, Eyal; Sade, Sharon; Fishman, Gadi; Ophir, Dov; Grankin, Mila; Katzir, Abraham

1998-07-01

A novel infrared (IR) transparent optical fiber coupled to a hand held otoscope and a radiometer was constructed and used to measure the temperatures of the tympanic membrane (TM) and to distinguish between diseased and healthy middle ears. A greater temperature difference between TM readings was found when Acute Otitis Media (AOM) existed in one of the ears examined. This supports the hypothesis that acute inflammation of the middle ear will result in elevated local temperature when measured in such a way that the reading is taken only from the TM without interference of the external canal. The use of an optical fiber enabled temperature measurements of the TM with high spatial resolution eliminating the external ear canal interference. A small patient population was examined and the initial results were statistically significant. In the hands of the primary care physician, this tool would prevent misdiagnosis of AOM preventing indiscriminate use of antibiotics and avoiding complications by early diagnosis.

Is Malassezia nana the main species in horses' ear canal microbiome?

PubMed

Aldrovandi, Ana Lúcia; Osugui, Lika; Acqua Coutinho, Selene Dall'

2016-01-01

The objective of this study was to characterize genotypically Malassezia spp. isolated from the external ear canal of healthy horses. Fifty-five horses, 39 (70.9%) males and 16 (29.1%) females, from different breeds and adults were studied. External ear canals were cleaned and a sterile cotton swab was introduced to collect cerumen. A total of 110 samples were cultured into Dixon medium and were incubated at 32°C for up to 15 days. Macro- and micromorphology and phenotypic identification were performed. DNA was extracted, strains were submitted to polymerase chain reaction technique, and the products obtained were submitted to Restriction Fragment Length Polymorphism using the restriction enzymes BstCI and HhaI. Strains were sent off to genetic sequencing of the regions 26S rDNA D1/D2 and ITS1-5.8S-ITS2 rDNA. Malassezia spp. were isolated from 33/55 (60%) animals and 52/110 (47%) ear canals. No growth on Sabouraud dextrose agar was observed, confirming the lipid dependence of all strains. Polymerase chain reaction-Restriction fragment length polymorphism permitted the molecular identification of Malassezia nana - 42/52 (81%) and Malassezia slooffiae - 10/52 (19%). Sequencing confirmed RFLP identification. It was surprising that M. nana represented over 80% of the strains and no Malassezia equina was isolated in this study, differing from what was expected. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

Preventing collapse of external auditory meatus during audiometry.

PubMed

Pearlman, R C

1975-11-01

Occlusion of the external auditory meatus resulting from earphone pressure can produce a pseudoconductive hearing loss. I describe a method for detecting ear canal collapse by otoscopy and I suggest a method of correcting the problem with a polyethylene tube prosthesis.

Why Cannot We have an Etiological Classification for the Patients with Granular Myringitis?

PubMed

Bansal, Mohan

2017-09-01

Though granular myringitis (GM) is not a very rare disease it does not have any classification. Its exact etiology is not known. The granulations on tympanic membrane also occur in association with other lesions of external auditory canal (EAC) and middle ear. The aims of this study were to know the etiological factors of GM and classify the disease according to its etiological factors and associated disorders of EAC and middle ear. Data were retrieved from the search of four electronic databases: PubMed, EMBASE, Cochrane Library, and Google scholar. Relevant articles were also sought by a hand search review of reference books. The databases were searched using the key words otitis externa, external otitis, granular myringitis, granular otitis externa and myringitis. Data were extracted using a pre-defined data-extraction form. The following data were recorded (1) etiological and predisposing conditions; (2) pathological features; (3) associated disorders of external and middle ear. The study proposes the etiological classification of GM. It suggests two major groups: primary and secondary. The primary GM is basically idiopathic and these patients do no have evidences of any other types of otitis media and otitis externa. In the secondary GM the cause is obvious and the patients usually have associated otitis media and/or lesions of external ear canal. Author speculates that habit of self ear cleaning/scratching is a specific etiological factor in cases of primary GM but more studies are required to confirm this theory.

Auricular syncope.

PubMed

Thakar, A; Deepak, K K; Kumar, S Shyam

2008-10-01

To describe a previously unreported syndrome of recurrent syncopal attacks provoked by light stimulation of the external auditory canal. A 13-year-old girl had been receiving treatment for presumed absence seizures, with inadequate treatment response. Imaging was normal. Careful history taking indicated that the recurrent syncopal attacks were precipitated by external auditory canal stimulation. Targeted autonomic function tests confirmed a hyperactive vagal response, with documented significant bradycardia and lightheadedness, provoked by mild stimulation of the posterior wall of the left external auditory canal. Abstinence from ear scratching led to complete alleviation of symptoms without any pharmacological treatment. Reflex syncope consequent to stimulation of the auricular branch of the vagus nerve is proposed as the pathophysiological mechanism for this previously undocumented syndrome.

21 CFR 344.3 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 5 2011-04-01 2011-04-01 false Definitions. 344.3 Section 344.3 Food and Drugs... TOPICAL OTIC DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE General Provisions § 344.3 Definitions. As used... external ear canal that aids in the removal of excessive earwax. (c) Water-clogged ears. The retention of...

Finite element modelling of human auditory periphery including a feed-forward amplification of the cochlea.

PubMed

Wang, Xuelin; Wang, Liling; Zhou, Jianjun; Hu, Yujin

2014-08-01

A three-dimensional finite element model is developed for the simulation of the sound transmission through the human auditory periphery consisting of the external ear canal, middle ear and cochlea. The cochlea is modelled as a straight duct divided into two fluid-filled scalae by the basilar membrane (BM) having an orthotropic material property with dimensional variation along its length. In particular, an active feed-forward mechanism is added into the passive cochlear model to represent the activity of the outer hair cells (OHCs). An iterative procedure is proposed for calculating the nonlinear response resulting from the active cochlea in the frequency domain. Results on the middle-ear transfer function, BM steady-state frequency response and intracochlear pressure are derived. A good match of the model predictions with experimental data from the literatures demonstrates the validity of the ear model for simulating sound pressure gain of middle ear, frequency to place map, cochlear sensitivity and compressive output for large intensity input. The current model featuring an active cochlea is able to correlate directly the sound stimulus in the ear canal with the vibration of BM and provides a tool to explore the mechanisms by which sound pressure in the ear canal is converted to a stimulus for the OHCs.

Aviation Fuel Exposure Resulting in Otitis Externa with Vertigo.

PubMed

Long, Robert J; Charles, Reese A

2018-07-01

Otitis externa secondary to irritant or chemical exposure is well documented; however, specifically secondary to jet fuel exposure and its associated toxicology is not. Over 2 million military and civilian personnel per year are occupationally exposed to aviation fuels. An aircraft maintainer presented with noninfectious acute otitis externa secondary to external ear canal exposure to JP-5 jet fuel. Proper exposure guidelines were followed, but it was not realized that the external ear canal was involved. The first symptoms to emerge were vertigo, dizziness, and disequilibrium; however, on physical exam it appeared that there was no middle ear involvement. Otitis externa normally does not present with vestibular symptoms as the pathology affects the external ear canal dermal tissue. Upon review of JP-5's toxicology profile, dermal absorption is a route of entry and can cause general neurological symptoms, including loss of coordination. This case highlights potential deficiencies in the standardized safety data sheets that are used after exposure. Without mention of possible auricular exposure one may focus on the logical protection of the eyes, mouth, and visible skin. This is concerning due to potential delayed exposure symptoms, dermal absorption, high level of dermal destruction, and the close proximity to the sensory system. The goal of this case report is to improve the knowledge of providers caring for personnel who may be exposed and to suggest possible revisions to the Safety Data Sheets for jet fuel.Long RJ, Charles RA. Aviation fuel exposure resulting in otitis externa with vertigo. Aerosp Med Hum Perform. 2018; 89(7):661-663.

Primary Synovial Sarcoma of External Auditory Canal: A Case Report.

PubMed

Devi, Aarani; Jayakumar, Krishnannair L L

2017-07-20

Synovial sarcoma is a rare malignant tumor of mesenchymal origin. Primary synovial sarcoma of the ear is extremely rare and to date only two cases have been published in English medical literature. Though the tumor is reported to have an aggressive nature, early diagnosis and treatment may improve the outcome. Here, we report a rare case of synovial sarcoma of the external auditory canal in an 18-year-old male who was managed by chemotherapy and referred for palliation due to tumor progression.

Underwater hearing and sound localization with and without an air interface.

PubMed

Shupak, Avi; Sharoni, Zohara; Yanir, Yoav; Keynan, Yoav; Alfie, Yechezkel; Halpern, Pinchas

2005-01-01

Underwater hearing acuity and sound localization are improved by the presence of an air interface around the pinnae and inside the external ear canals. Hearing threshold and the ability to localize sound sources are reduced underwater. The resonance frequency of the external ear is lowered when the external ear canal is filled with water, and the impedance-matching ability of the middle ear is significantly reduced due to elevation of the ambient pressure, the water-mass load on the tympanic membrane, and the addition of a fluid-air interface during submersion. Sound lateralization on land is largely explained by the mechanisms of interaural intensity differences and interaural temporal or phase differences. During submersion, these differences are largely lost due to the increase in underwater sound velocity and cancellation of the head's acoustic shadow effect because of the similarity between the impedance of the skull and the surrounding water. Ten scuba divers wearing a regular opaque face mask or an opaque ProEar 2000 (Safe Dive, Ltd., Hofit, Israel) mask that enables the presence of air at ambient pressure in and around the ear made a dive to a depth of 3 m in the open sea. Four underwater speakers arranged on the horizontal plane at 90-degree intervals and at a distance of 5 m from the diver were used for testing pure-tone hearing thresholds (PTHT), the reception threshold for the recorded sound of a rubber-boat engine, and sound localization. For sound localization, the sound of the rubber boat's engine was randomly delivered by one speaker at a time at 40 dB HL above the recorded sound of a rubber-boat engine, and the diver was asked to point to the sound source. The azimuth was measured by the diver's companion using a navigation board. Underwater PTHT with both masks were significantly higher for frequencies of 250 to 6000 Hz when compared with the thresholds on land (p <0.0001). No differences were found in the PTHT or the reception threshold for the recorded sound of a rubber-boat engine for dry or wet ear conditions. There was no difference in the sound localization error between the regular mask and the ProEar 2000 mask. The presence of air around the pinna and inside the external ear canal did not improve underwater hearing sensitivity or sound localization. These results support the argument that bone conduction plays the main role in underwater hearing.

Comparison of Microbiological Flora in the External Auditory Canal of Normal Ear and an Ear with Acute Otitis Externa.

PubMed

Ghanpur, Asheesh Dora; Nayak, Dipak Ranjan; Chawla, Kiran; Shashidhar, V; Singh, Rohit

2017-09-01

Acute Otitis Externa (AOE) is also known as swimmer's ear. Investigations initiated during World War II firmly established the role of bacteria in the aetiology of Acute Otitis Externa. To culture the microbiological flora of the normal ear and compare it with the flora causing AOE and to know the role of normal ear canal flora and anaerobes in the aetiology. A prospective observational study was conducted on 64 patients clinically diagnosed with unilateral AOE. Ear swabs were taken from both the ears. Microbiological flora was studied considering diseased ear as test ear and the normal ear as the control. Aerobic and anaerobic cultures were done. Severity of the disease was assessed by subjective and objective scores. Effect of topical treatment with ichthammol glycerine pack was assessed after 48 hours and scores were calculated again. Patients with scores < 4 after pack removal were started on systemic antibiotics and were assessed after seven days of antibiotics course. Data was analysed using Paired t-test, Wilcoxon signed ranks test and Chi-square test. A p-value < 0.05 was considered significant. Pseudomonas aeruginosa (33%) was the most common bacteria cultured from the ear followed by Methicillin Resistant Staphylococcus aureus (MRSA) (18%). Patients with anaerobic organism in the test ear had severe symptoms and needed systemic antibiotic therapy. Most of the cases may respond to empirical antibiotic therapy. In cases with severe symptoms and the ones refractory to empirical treatment, a culture from the ear canal will not be a tax on the patient. This helps in giving a better understanding about the disease, causative organisms and helps in avoiding the use of inappropriate antibiotics that usually result in developing resistant strains of bacteria.

Turicella otitidis and Corynebacterium auris: 20 years on.

PubMed

von Graevenitz, A; Funke, G

2014-02-01

Turicella otitidis and Corynebacterium auris, described as new species 20 years ago, have been isolated mainly from the external ear canal and middle ear fluid. While their taxonomic position has been clearly established, their diagnosis in the routine laboratory is difficult. The question of their pathogenic potential in otitis is still open but might be elucidated better if corynebacteria are speciated more often.

Carcinoma of the middle ear and external auditory canal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hahn, S.S.; Kim, J.A.; Goodchild, N.

1983-07-01

Thirty-one patients with malignant tumors of the middle ear and external auditory canal (EAC) were observed at the University of Virginia Hospital from 1956 through 1980. Of 27 patients with carcinoma, 21 had squamous cell carcinoma, 4 had basal cell carcinoma and 2 had adenoid cystic carcinoma. The 27 patients with carcinoma are reviewed with regard to clinical presentation, treatment modality, results and complications. The majority (67%) of patients had a history of chronic ear drainage, 22% had a previous mastoidectomy or polypectomy and 7% had an associated cholesteatoma. Eighty percent of patients with carcinoma limited to EAC were alivemore » and well at 5 years, compared to 43% of patients with involvement of the middle ear. Fifty-six percent of patients without invasion of the petrous bone were alive at 5 years compared to only 20% of patients with petrous bone involvement. The data strongly suggest that survival depends on the extent of disease. The corrected disease free 5 year survival rates were 14% for patients who had surgery alone and 50% for those who had surgery and radiotherapy. Of the three patients with advanced disease who received radiotherapy alone, none survived five years.« less

External Auditory Canal Dimensions, Age, and Cerumen Retention or Impaction in Persons With Down Syndrome.

PubMed

Dy, Alexander Edward S; Lapeña, José Florencio F

2018-04-01

To investigate associations between age, external auditory canal (EAC) dimensions, and cerumen retention/impaction among persons with Down syndrome (DS). This cross-sectional study evaluated EAC dimensions, cerumen retention/impaction, and middle ear status with pneumatoscopy after extraction in 130 persons with DS. Descriptive and inferential statistics correlated age, presence of impacted/retained cerumen, and EAC diameter. Of 260 ears in 67 males and 63 females with average age of 9.48 years, 72.3% (188) had EAC of ≤4 mm. Those ≤1 year were 4.97 times more likely to have cerumen problems than those >1 year (95% CI, 1.45-17.02, P = .011). The odds of having cerumen problems with an EAC diameter of ≤4 mm were 3.31 times higher than with a diameter of 5 mm (95% CI, 1.46-7.50, P = .004), and odds of having cerumen impaction were as much as 6.19 times higher (95% CI, 2.38-16.08, P < .001). Male gender and low-lying external ear were also associated with increased odds of cerumen problems. There is a high prevalence of cerumen retention/impaction in persons with DS compared to the general Philippine population and a higher prevalence rate for EAC stenosis than elsewhere. A canal diameter of 4 mm and below and age 1 year or less are associated with a significantly higher likelihood of cerumen retention/impaction.

Primary Synovial Sarcoma of External Auditory Canal: A Case Report

PubMed Central

Jayakumar, Krishnannair l L

2017-01-01

Synovial sarcoma is a rare malignant tumor of mesenchymal origin. Primary synovial sarcoma of the ear is extremely rare and to date only two cases have been published in English medical literature. Though the tumor is reported to have an aggressive nature, early diagnosis and treatment may improve the outcome. Here, we report a rare case of synovial sarcoma of the external auditory canal in an 18-year-old male who was managed by chemotherapy and referred for palliation due to tumor progression. PMID:28948118

[Basics of Ear Surgery].

PubMed

Lailach, S; Zahnert, T

2016-12-01

The present article about the basics of ear surgery is a short overview of current indications, the required diagnostics and surgical procedures of common otologic diseases. In addition to plastic and reconstructive surgery of the auricle, principles of surgery of the external auditory canal, basics of middle ear surgery and the tumor surgery of the temporal bone are shown. Additionally, aspects of the surgical hearing rehabilitation (excluding implantable hearing systems) are presented considering current study results. Georg Thieme Verlag KG Stuttgart · New York.

Ear canal dynamic motion as a source of power for in-ear devices

NASA Astrophysics Data System (ADS)

Delnavaz, Aidin; Voix, Jérémie

2013-02-01

Ear canal deformation caused by temporomandibular joint (jaw joint) activity, also known as "ear canal dynamic motion," is introduced in this paper as a candidate source of power to possibly recharge hearing aid batteries. The geometrical deformation of the ear canal is quantified in 3D by laser scanning of different custom ear moulds. An experimental setup is proposed to measure the amount of power potentially available from this source. The results show that 9 mW of power is available from a 15 mm3 dynamic change in the ear canal volume. Finally, the dynamic motion and power capability of the ear canal are investigated in a group of 12 subjects.

Hands-free device control using sound picked up in the ear canal

NASA Astrophysics Data System (ADS)

Chhatpar, Siddharth R.; Ngia, Lester; Vlach, Chris; Lin, Dong; Birkhimer, Craig; Juneja, Amit; Pruthi, Tarun; Hoffman, Orin; Lewis, Tristan

2008-04-01

Hands-free control of unmanned ground vehicles is essential for soldiers, bomb disposal squads, and first responders. Having their hands free for other equipment and tasks allows them to be safer and more mobile. Currently, the most successful hands-free control devices are speech-command based. However, these devices use external microphones, and in field environments, e.g., war zones and fire sites, their performance suffers because of loud ambient noise: typically above 90dBA. This paper describes the development of technology using the ear as an output source that can provide excellent command recognition accuracy even in noisy environments. Instead of picking up speech radiating from the mouth, this technology detects speech transmitted internally through the ear canal. Discreet tongue movements also create air pressure changes within the ear canal, and can be used for stealth control. A patented earpiece was developed with a microphone pointed into the ear canal that captures these signals generated by tongue movements and speech. The signals are transmitted from the earpiece to an Ultra-Mobile Personal Computer (UMPC) through a wired connection. The UMPC processes the signals and utilizes them for device control. The processing can include command recognition, ambient noise cancellation, acoustic echo cancellation, and speech equalization. Successful control of an iRobot PackBot has been demonstrated with both speech (13 discrete commands) and tongue (5 discrete commands) signals. In preliminary tests, command recognition accuracy was 95% with speech control and 85% with tongue control.

The ototoxic effect of intratympanic terbinafine applied in the middle ear of rats

PubMed Central

2013-01-01

Background Otomycosis is defined as an infection of the external ear canal with fungal agents. The treatment of the disease is cleansing and drying of the external ear canal, identification and treatment of any predisposing factors and application of topical antifungal agents. Terbinafine is used as an antifungal agent to treat otomycosis. We proposed to investigate the probable ototoxic effect of terbinafine solution on auditory brain stem response (ABR) and distortion product otoacoustic emission (DPOAE) when applied intratympanically in the middle ear of rats. Methods The experiment was performed on 30 female Wistar albino rats. Thirty animals were divided into three groups of 10 animals each. 1% terbinafine solution was administered to the first group (group T). The second group (group G) was administered 40 mg/ml gentamicin solution (ototoxic control). The third group (group S) was administered saline solution (negative control). Baseline DPOAE measurements and ABR testing from the left ears were obtained from the animals in all groups under general anesthesia. Ear solutions were applied in the middle ear intratympanically with a dental needle. Treatment was initiated after baseline measurements and repeated once every two days for fifteen days. Results Pre and post-treatment DPOAE responses for all tested frequencies of group T and Group S showed no statistically significant difference. However, the group G demonstrated a significant change in ABR thresholds and DPOAE responses. Conclusions Terbinafine solution is a broad spectrum antifungal agent effective in the treatment of otomycosis. The present study demonstrated that its direct administration in the middle ear of rats does not affect inner ear function as measured by ABR and DPOAE responses. PMID:23663536

Computed tomographic features of the osseous structures of the external acoustic meatus, tympanic cavity, and tympanic bulla of llamas (Lama glama).

PubMed

Concha-Albornoz, Ismael; Stieger-Vanegas, Susanne M; Cebra, Christopher K

2012-01-01

To evaluate the osseous structures of the external acoustic meatus, tympanic cavity, and tympanic bulla of llamas (Lama glama) by use of computed tomography (CT) and establish measurement values for use in detection of abnormalities associated with the external or middle ear in llamas. 10 adult llama heads without any evidence of ear disease. Heads of 10 healthy llamas euthanized by use of a captive bolt striking the dorsal aspect of the skull were collected. Transverse images of the heads were acquired with 1-mm slice thickness, and images were reconstructed in sagittal and dorsal planes. Measurements of the bony structures of the external and middle ear of each head were obtained. The osseous external acoustic meatus curved ventrally as it tracked medially. Its narrowest portion was located at the level of the tympanic annulus. The tympanic bulla conformation differed widely from the bubble-shaped tympanic bulla in dogs and cats. The bulla was divided by the stylohyoid fossa into a larger caudolateral and a smaller caudomedial process; its interior had a honeycombed structure with pneumatized cells similar to the honeycombed appearance of the human mastoid process. Results provided new information regarding the shape and dimensions of the osseous external and middle ear structures in adult llamas without ear disease. Specific landmarks for location of the external acoustic meatus, tympanic cavity, and tympanic bulla in relation to each other were identified. Knowledge of the CT appearance of normal structures will help clinicians to identify changes attributable to middle ear otitis, external ear canal stenosis, or congenital malformations of the ear in this species.

Inverse solution of ear-canal area function from reflectance

PubMed Central

Rasetshwane, Daniel M.; Neely, Stephen T.

2011-01-01

A number of acoustical applications require the transformation of acoustical quantities, such as impedance and pressure that are measured at the entrance of the ear canal, to quantities at the eardrum. This transformation often requires knowledge of the shape of the ear canal. Previous attempts to measure ear-canal area functions were either invasive, non-reproducible, or could only measure the area function up to a point mid-way along the canal. A method to determine the area function of the ear canal from measurements of acoustic impedance at the entrance of the ear canal is described. The method is based on a solution to the inverse problem in which measurements of impedance are used to calculate reflectance, which is then used to determine the area function of the canal. The mean ear-canal area function determined using this method is similar to mean ear-canal area functions measured by other researchers using different techniques. The advantage of the proposed method over previous methods is that it is non- invasive, fast, and reproducible. PMID:22225043

Congenital Auricular Malformations: Description of Anomalies and Syndromes.

PubMed

Bartel-Friedrich, Sylva

2015-12-01

Half of the malformations in the ear, nose, and throat region affect the ear. Malformations of the external ear (pinna or auricle with external auditory canal [EAC]) are collectively termed microtia. Microtia is a congenital anomaly that ranges in severity from mild structural abnormalities to complete absence of the external ear (anotia). Microtia occurs more frequently in males (∼2 or 3:1), is predominantly unilateral (∼70-90%), and more often involves the right ear (∼60%). The reported prevalence varies geographically from 0.83 to 17.4 per 10,000 births. Microtia may be genetic (with family history, spontaneous mutations) or acquired. Malformations of the external ear can also involve the middle ear and/or inner ear. Microtia may be an isolated birth defect, but associated anomalies or syndromes are described in 20 to 60% of cases, depending on study design. These generally fit within the oculo-auriculo-vertebral spectrum; defects are located most frequently in the facial skeleton, facial soft tissues, heart, and vertebral column, or comprise a syndrome (e.g., Treacher Collins syndrome). Diagnostic investigation of microtia includes clinical examination, audiologic testing, genetic analysis and, especially in higher grade malformations with EAC deformities, computed tomography (CT) or cone-beam CT for the planning of surgery and rehabilitation procedures, including implantation of hearing aids. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Effect of Diving and Diving Hoods on the Bacterial Flora of the External Ear Canal and Skin

DTIC Science & Technology

1982-05-01

in parentheses itidicate number of sites tested. b One strain isolated from skin laceration exposed to water. "Diver developed external otitis media 5... otitis media (11), skin infections skin of wearing diving hoods in and out of the (6), and diarrheal diseases (10). One aspect of water. We

Epidemiology of subclinical ovine psoroptic otoacariasis in Great Britain.

PubMed

Bates, P G

1996-04-20

Seven sheep flocks with subclinical psoroptic otoacariasis were investigated. Psoroptes species mites were isolated from 3.1 per cent of the 2676 sheep examined and the prevalence in the flocks ranged between 1.3 and 23.9 per cent, with the highest infestations in pedigree flocks. Unilateral or bilateral infestations were found in sheep of all ages. Adult and shearling rams, with prevalences of 21.5 and 14.2 per cent, respectively, were the most affected and two lambs, two and eight days old, were the youngest to be infested. There was no evidence of vertical transmission. The infestation affected several breeds of sheep. No other known hosts for Psoroptes species present on the premises were shown to be infested. Non-parasitic for-age mites were also isolated from the ear canals of the sheep and may have contributed to the clinical signs which, in adult sheep, ranged from aural haematomas/fibrosis (cauliflower ears), and violent head shaking and ear rubbing leading to excoriation and wounding of the ear and base of the ear. The signs in lambs included plaques of scab (often bloody) on the external ear cleft, excoriation of the base of the ear, ear scratching with the hind feet and inflammation of the external aspects of the horizontal canal. In all cases the internal pinnae were clear of typical psoroptic scabs. Psoroptes mites were isolated from 28.6 per cent of the damaged ears and from 7.8 per cent of the undamaged ears. There was no evidence of classical sheep scab in any of the flocks. Plunge dipping in diazinon, propetamphos or flumethrin, or the use of synthetic pyrethroid pour-on preparations and an oral drench of ivermectin had little effect because ear mite infestations were detected in the flocks after these treatments. An injection of ivermectin at 200 micrograms/kg bodyweight effectively eradicated the infestations when it was administered to these infested flocks.

Acceleration induced water removal from ear canals.

NASA Astrophysics Data System (ADS)

Kang, Hosung; Averett, Katelee; Jung, Sunghwan

2017-11-01

Children and adults commonly experience having water trapped in the ear canals after swimming. To remove the water, individuals will shake their head sideways. Since a child's ear canal has a smaller diameter, it requires more acceleration of the head to remove the trapped water. In this study, we theoretically and experimentally investigated the acceleration required to break the surface meniscus of the water in artificial ear canals and hydrophobic-coated glass tubes. In experiments, ear canal models were 3D-printed from a CT-scanned human head. Also, glass tubes were coated with silane to match the hydrophobicity in ear canals. Then, using a linear stage, we measured the acceleration values required to forcefully eject the water from the artificial ear canals and glass tubes. A theoretical model was developed to predict the critical acceleration at a given tube diameter and water volume by using a modified Rayleigh-Taylor instability. Furthermore, this research can shed light on the potential of long-term brain injury and damage by shaking the head to push the water out of the ear canal. This research was supported by National Science Foundation Grant CBET-1604424.

External ear canal exostosis and otitis media in temporal bones of prehistoric and historic chilean populations. A paleopathological and paleoepidemiological study.

PubMed

Castro, Mario; Goycoolea, Marcos; Silva-Pinto, Verónica

2017-04-01

External ear canal exostosis is more prevalent in northern coastal groups than in the highlands, suggesting that ocean activities facilitate the appearance of exostosis. However, southern coastal groups exposed to colder ocean water have a lesser incidence of exostosis, possibly due to less duration of exposure. There was a high incidence of otitis media in all groups of native population in Chile. One coastal group had a higher incidence, presumably due to racial factors. This is a paleopathological and paleoepidemiological study in temporal bones which assesses external ear canal exostosis and otitis media in prehistoric and historic native populations in Chile. A total of 460 temporal bones were evaluated for exostosis (ex) and 542 temporal bones were evaluated for otitis media (om). The study involved four groups: (1) Prehistoric Coastal (400-1000 AD) populations in Northern Chile (Pisagua-Tiwanaku) (22 temporal bones ex; 28 om); (2) Prehistoric Highland (400-1000 AD) populations in Northern Chile (292 temporal bones ex; 334 om); (3) Pisagua-Regional Developments (coastal) in Northern Chile (1000-1450 AD) (66 temporal bones ex; 82 om); and (4) Historic (1500-1800 AD) coastal populations in Southern Chile (80 temporal bones ex: 18 Chonos, 62 Fuegians. 98 om: 22 Chonos, 76 Fuegians). Skulls were evaluated visually and with an operating microscope. In addition, the otitis media group was evaluated with Temporal bone radiology - -lateral XRays-Schuller view - to assess pneumatization as evidence of previous middle ear disease. Prehistoric northern coastal groups had an incidence of exostosis of 15.91%, the northern highlands group 1.37%, and the southern coastal group 1.25%. There were changes suggestive of otitis media in: Pisagua/Tiwanaku 53.57%; Pisagua/Regional Developments 70.73%; Northern Highlands population 47.90%; Chonos 63.64%; and Fuegian tribes 64.47%.

The Surgical Challenge of Carotid Artery and Fallopian Canal Dehiscence in Chronic Ear Disease: A Pitfall for Endoscopic Approach

PubMed Central

Pauna, Henrique F.; Monsanto, Rafael C.; Schachern, Patricia A.; Costa, Sady S.; Kwon, Geeyoun; Paparella, Michael M.; Cureoglu, Sebahattin

2016-01-01

Objective Endoscopic procedures are becoming common in middle ear surgery. Inflammation due to chronic ear disease can cause bony erosion of the carotid artery and Fallopian canals, making them more vulnerable during surgery. The objective of this study was to determine whether or not chronic ear disease increases dehiscence of the carotid artery and Fallopian canals. Design Comparative human temporal bone study. Setting Otopathology laboratory. Participants We selected 78 temporal bones from 55 deceased donors with chronic otitis media or cholesteatoma, and then compared those 2 groups with a control group of 27 temporal bones from 19 deceased donors with no middle ear disease. Main outcome measures We analyzed the middle ear, carotid artery canal, and Fallopian canal, looking for signs of dehiscence of its bony coverage, using light microscopy. Results We found an increased incidence in dehiscence of the carotid artery and Fallopian canals in temporal bones with chronic middle ear disease. The size of the carotid artery canal dehiscence was larger in the middle ear diseased groups, and its bony coverage, when present, was also thinner compared to the control group. Dehiscence of the carotid artery canal was more frequently located closer to the promontory. The incidence of Fallopian canal dehiscence was significantly higher in temporal bones from donors older than 18 years with chronic middle ear disease. Conclusion The increased incidence of the carotid artery and Fallopian canal dehiscence in temporal bones with chronic middle ear disease elevates the risk of adverse events during middle ear surgery. Level of Evidence N/A. PMID:27455393

Contralateral Occlusion Test: The effect of external ear canal occlusion on hearing thresholds.

PubMed

Reis, Luis Roque; Fernandes, Paulo; Escada, Pedro

Bedside testing with tuning forks may decrease turnaround time and improve decision making for a quick qualitative assessment of hearing loss. The purpose of this study was to quantify the effects of ear canal occlusion on hearing, in order to decide which tuning fork frequency is more appropriate to use for quantifying hearing loss with the Contralateral Occlusion Test. Twenty normal-hearing adults (forty ears) underwent sound field pure tone audiometry with and without ear canal occlusion. Each ear was tested with the standard frequencies. The contralateral ear was suppressed with by masking. Ear occlusion was performed by two examiners. Participants aged between 21 and 30 years (25.6±3.03 years) showed an increase in hearing thresholds with increasing frequencies from 19.94dB (250Hz) to 39.25dB (2000Hz). The threshold difference between occluded and unoccluded conditions was statistically significant and increased from 10.69dB (250Hz) to 32.12dB (2000Hz). There were no statistically significant differences according to gender or between the examiners. The occlusion effect increased the hearing thresholds and became more evident with higher frequencies. The occlusion method as performed demonstrated reproducibility. In the Contralateral Occlusion Test, 256Hz or 512Hz tuning forks should be used for diagnosis of mild hearing loss, and a 2048Hz tuning fork should be used for moderate hearing loss. Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Cirugía de Cabeza y Cuello. All rights reserved.

Effects of a sensory branch to the posterior external ear canal: coughing, pain, Ramsay Hunt's syndrome and Hitselberger's sign.

PubMed

Mulazimoglu, S; Flury, R; Kapila, S; Linder, T

2017-04-01

A distinct nerve innervating the external auditory canal can often be identified in close relation to the facial nerve when gradually thinning the posterior canal wall. This nerve has been attributed to coughing during cerumen removal, neuralgic pain, Hitselberger's sign and vesicular eruptions described in Ramsay Hunt's syndrome. This study aimed to demonstrate the origin and clinical impact of this nerve. In patients with intractable otalgia or severe coughing whilst inserting a hearing aid, who responded temporarily to local anaesthesia, the symptoms could be resolved by sectioning a sensory branch to the posterior canal. In a temporal bone specimen, it was revealed that this nerve is predominantly a continuation of Arnold's nerve, also receiving fibres from the glossopharyngeal nerve and facial nerve. Histologically, the communicating branch from the facial nerve was confirmed. Surgeons should be aware of the posterior auricular sensory branch and its clinical implications.

21 CFR 524.1484f - Neomycin sulfate, prednisolone acetate, tetracaine hydrochloride eardrops.

Code of Federal Regulations, 2010 CFR

2010-04-01

...-susceptible organisms and/or allergy. In otitis externa, 2 to 6 drops may be placed in the external ear canal... hypersensitivity or allergy. If such signs are noted, therapy should be stopped.1 (3) Federal law restricts this...

Ear abnormalities in patients with oculo-auriculo-vertebral spectrum (Goldenhar syndrome).

PubMed

Rosa, Rafael Fabiano Machado; Silva, Alessandra Pawelec da; Goetze, Thayse Bienert; Bier, Bianca de Almeida; Almeida, Sheila Tamanini de; Paskulin, Giorgio Adriano; Zen, Paulo Ricardo Gazzola

2011-01-01

Oculo-auriculo-vertebral spectrum (OAVS) is a rare condition characterized by the involvement of the first branchial arches. To investigate the ear abnormalities of a sample of patients with OAVS. The sample consisted of 12 patients with OAVS seen at the Clinical Genetics Unit, UFCSPA/CHSCPA. The study included only patients who underwent mastoid computed tomography and with normal karyotype. We performed a review of its clinical features, giving emphasis to the ear findings. Nine patients were male, the ages ranged from 1 day to 17 years. Ear abnormalities were observed in all patients and involved the external (n = 12), middle (n = 10) and inner ear (n = 3). Microtia was the most frequent finding (n = 12). The most common abnormalities of the middle ear were: opacification (n = 2), displacement (n = 2) and malformation of the ossicular chain. Agenesis of the internal auditory canal (n = 2) was the most frequent alteration of the inner ear. Ear abnormalities are variable in patients with OAVS and often there is no correlation between findings in the external, middle and inner ear. The evaluation of these structures is important in the management of individuals with OAVS.

[Severe Bleeding from the Middle Ear Cavity after Myringotomy: Review Based on a Case Report].

PubMed

Hofmann, Veit M; Niehues, Stefan M; Albers, Andreas E; Pudszuhn, Annett

2017-03-01

Report of a rare case of severe bleeding from the middle ear cavity after myringotomy. On the basis of the case report, the procedure for such bleeding is discussed in the context of the literature. A 6-year-old boy received a revision myringotomy in an ambulant setting. During the procedure a severe bleeding occurred. The external auditory canal was adequately packed. The patient was extubated and transferred to the clinic as an emergency. Computer tomography of the temporal bone showed the anatomical variant of a dehiscent high jugular bulb, which had been injured. Because no rebleeding occurred, the packing of the ear canal was removed and an explorative tympanoscopy was performed on the third postoperative day. When the tympanomeatal flap was lifted, the defect in the jugular bulb was found. The lesion was covered with Tutopatch ® pads and fibrin glue and the auditory canal was packed again. After removal of the packing three weeks postoperatively a properly healed situs was found. No further measures were taken. The injury of a dehiscent jugular bulb in the course of ear surgeries leads to a massive hemorrhage. The case describes the diagnostic and therapeutic procedure for this relatively rare but severe complication. © Georg Thieme Verlag KG Stuttgart · New York.

Long-term Results of Troublesome CWD Cavity Reconstruction by Mastoid and Epitympanic Bony Obliteration (CWR-BOT) in Adults.

PubMed

Vercruysse, Jean-Philippe; van Dinther, Joost J S; De Foer, Bert; Casselman, Jan; Somers, Thomas; Zarowski, Andrzej; Cremers, Cor C; Offeciers, Erwin

2016-07-01

To present the long-term surgical outcome of the bony mastoid and epitympanic obliteration technique with canal wall reconstruction (CWR-BOT) in adults with an unstable cavity after previous canal wall-down surgery for extensive cholesteatoma. Retrospective study. Therapeutic. Tertiary referral center. Fifty consecutive adult patients undergoing a CWR-BOT between 1998 and 2009. (A) Recurrence and residual rates of cholesteatoma, (B) postoperative hygienic status of the ear, including postoperative aspect of the tympanic membrane and external ear canal integrity (EAC), (C) functional outcome, and (D) long-term safety issues. (A) The percentage of ears remaining safe without recurrent or residual disease after CWR-BOT was 96% after a mean follow-up time of 101.8 months. Recurrent cholesteatoma occurred in 2% (n = 1) and a residual cholesteatoma was detected in 2% (n = 1) of the patients. (B) A safe dry, and trouble-free graft and selfcleaning EAC was achieved in 94%. (C) The postoperative hearing results showed a gain of 1.7 dB on pure-tone average air-conduction. (D) Nonecho planar diffusion-weighted imaging (non-EP DW magnetic resonance imaging) documented the residual (n = 1) and recurrent cholesteatoma (n = 1). The 1- and 5-year imaging follow-up revealed no other recurrent or residual disease. The CWR-BOT is a safe and very effective option for treatment of problematic unstable canal wall-down mastoid cavities, resulting in dry trouble-free ears.

3D fiber deposited polymeric scaffolds for external auditory canal wall.

PubMed

Mota, Carlos; Milazzo, Mario; Panetta, Daniele; Trombi, Luisa; Gramigna, Vera; Salvadori, Piero A; Giannotti, Stefano; Bruschini, Luca; Stefanini, Cesare; Moroni, Lorenzo; Berrettini, Stefano; Danti, Serena

2018-05-07

The external auditory canal (EAC) is an osseocartilaginous structure extending from the auricle to the eardrum, which can be affected by congenital, inflammatory, and neoplastic diseases, thus reconstructive materials are needed. Current biomaterial-based approaches for the surgical reconstruction of EAC posterior wall still suffer from resorption (biological) and extrusion (synthetic). In this study, 3D fiber deposited scaffolds based on poly(ethylene oxide terephthalate)/poly(butylene terephthalate) were designed and fabricated to replace the EAC wall. Fiber diameter and scaffold porosity were optimized, leading to 200 ± 33 µm and 55% ± 5%, respectively. The mechanical properties were evaluated, resulting in a Young's modulus of 25.1 ± 7.0 MPa. Finally, the EAC scaffolds were tested in vitro with osteo-differentiated human mesenchymal stromal cells (hMSCs) with different seeding methods to produce homogeneously colonized replacements of interest for otologic surgery. This study demonstrated the fabrication feasibility of EAC wall scaffolds aimed to match several important requirements for biomaterial application to the ear under the Tissue Engineering paradigm, including shape, porosity, surface area, mechanical properties and favorable in vitro interaction with osteoinduced hMSCs. This study demonstrated the fabrication feasibility of outer ear canal wall scaffolds via additive manufacturing. Aimed to match several important requirements for biomaterial application to ear replacements under the Tissue Engineering paradigm, including shape, porosity and pore size, surface area, mechanical properties and favorable in vitro interaction with osteo-differentiated mesenchymal stromal cells.

First branchial cleft anomaly, a case for misdiagnosis.

PubMed

Lanisnik, Bostjan; Didanovic, Vojko; Cizmarevic, Bogdan

2004-01-01

First branchial cleft anomaly is a rare condition that is often misdiagnosed and falsely mistreated before complete and definitive surgical treatment. Its origin is uncertain and the presence of ectodermal and sometimes also mesodermal elements has led some authors to the conclusion that it represents buried nests of cells forming the first branchial cleft and the underlying mesoderm. First branchial cleft anomaly can be presented as a cystic lesion, fistula or sinus extending towards the membranous external ear canal. The sinus tract runs through the parotid gland in close association with the facial nerve. There is no imaging method capable of identifying a first branchial cleft anomaly with certainty. The danger of facial nerve injury during surgery and the failure to identify the sinus tract running to the external ear canal are the main reasons for incomplete excision. The facial nerve must be identified and preserved and the lesion completely excised. Facial nerve injury is more common in attempts to remove recurrent branchial cleft lesions.

Up-regulation of peroxidase proliferator-activated receptor gamma in cholesteatoma.

PubMed

Hwang, Soon Jae; Kang, Hee Joon; Song, Jae-Jun; Kang, Jae Seong; Woo, Jeong Soo; Chae, Sung Won; Lee, Heung-Man

2006-01-01

To evaluate the localization and expression of peroxidase proliferator-activated receptor (PPAR)gamma in cholesteatoma epithelium. Experimental study. Reverse-transcription polymerase chain reaction was performed on cholesteatoma tissues from 10 adult patients undergoing tympanomastoid surgery for middle ear cholesteatoma and on 10 samples of normal external auditory canal skin tissue. The expression levels of PPARgamma to glyceraldehyde-3-phosphate dehydrogenase transcripts were semiquantified by densitometry. We also characterized the cellular localization of the PPARgamma protein immunohistochemically. Ki-67 was also localized to compare the proliferative activity of cells in cholesteatoma epithelium and in normal external auditory canal skin. PPARgamma mRNA and protein were detected in normal external auditory canal skin and in cholesteatoma epithelium. The expression level of PPARgamma mRNA in cholesteatoma was significantly increased compared with that in normal external auditory canal skin. PPARgamma protein was expressed in cells mainly in the granular and prickle cell layers. However, the intensity of its expression was generally decreased in the parabasal layer of the cholesteatoma epithelium. Ki-67 was expressed in the nuclei of cells in the basal and parabasal layers, and a greater number of cells were Ki-67 immunopositive in cholesteatoma epithelium. PPARgamma is up-regulated in the cholesteatoma epithelium compared with normal external auditory canal skin. These results suggest that PPARgamma may play an important role in the pathogenesis of cholesteatoma.

Postoperative Intensity-Modulated Radiotherapy for Squamous Cell Carcinoma of the External Auditory Canal and Middle Ear: Treatment Outcomes, Marginal Misses, and Perspective on Target Delineation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Wan-Yu; Kuo, Sung-Hsin; Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei, Taiwan

Purpose: To report outcomes of the rare disease of squamous cell carcinoma (SCC) of the external auditory canal (EAC) and middle ear treated with surgery and postoperative intensity-modulated radiotherapy (IMRT). Failure patterns related to spatial dose distribution were also analyzed to provide insight into target delineation. Methods and Materials: A retrospective review was conducted of the records of 11 consecutive patients with SCC of the EAC and middle ear who were treated with curative surgery and postoperative IMRT at one institution between January 2007 and February 2010. The prescribed IMRT dose was 60 to 66 Gy at 2 Gy permore » fraction. Three patients also received concurrent cisplatin-based chemotherapy, and 1 patient received concurrent oral tegafur/uracil. The median follow-up time was 19 months (range, 6-33 months). Results: Four patients had locoregional recurrence, yielding an estimated 2-year locoregional control rate of 70.7%. Among them, 1 patient had persistent disease after treatment, and 3 had marginal recurrence. Distant metastasis occurred in 1 patient after extensive locoregional recurrence, yielding an estimated 2-year distant control rate of 85.7%. The estimated 2-year overall survival was 67.5%. The three cases of marginal recurrence were near the preauricular space and glenoid fossa of the temporomandibular joint, adjacent to the apex of the ear canal and glenoid fossa of the temporomandibular joint, and in the postauricular subcutaneous area and ipsilateral parotid nodes, respectively. Conclusions: Marginal misses should be recognized to improve target delineation. When treating SCC of the EAC and middle ear, care should be taken to cover the glenoid fossa of the temporomandibular joint and periauricular soft tissue. Elective ipsilateral parotid irradiation should be considered. The treatment planning procedure should also be refined to balance subcutaneous soft-tissue dosimetry and toxicity.« less

Postoperative intensity-modulated radiotherapy for squamous cell carcinoma of the external auditory canal and middle ear: treatment outcomes, marginal misses, and perspective on target delineation.

PubMed

Chen, Wan-Yu; Kuo, Sung-Hsin; Chen, Yu-Hsuan; Lu, Szu-Huai; Tsai, Chiao-Ling; Cheng, Jason Chia-Hsien; Hong, Ruey-Long; Chen, Ya-Fang; Hsu, Chuan-Jen; Lin, Kai-Nan; Ko, Jenq-Yuh; Lou, Pei-Jen; Wang, Cheng-Ping; Chong, Fok-Ching; Wang, Chun-Wei

2012-03-15

To report outcomes of the rare disease of squamous cell carcinoma (SCC) of the external auditory canal (EAC) and middle ear treated with surgery and postoperative intensity-modulated radiotherapy (IMRT). Failure patterns related to spatial dose distribution were also analyzed to provide insight into target delineation. A retrospective review was conducted of the records of 11 consecutive patients with SCC of the EAC and middle ear who were treated with curative surgery and postoperative IMRT at one institution between January 2007 and February 2010. The prescribed IMRT dose was 60 to 66 Gy at 2 Gy per fraction. Three patients also received concurrent cisplatin-based chemotherapy, and 1 patient received concurrent oral tegafur/uracil. The median follow-up time was 19 months (range, 6-33 months). Four patients had locoregional recurrence, yielding an estimated 2-year locoregional control rate of 70.7%. Among them, 1 patient had persistent disease after treatment, and 3 had marginal recurrence. Distant metastasis occurred in 1 patient after extensive locoregional recurrence, yielding an estimated 2-year distant control rate of 85.7%. The estimated 2-year overall survival was 67.5%. The three cases of marginal recurrence were near the preauricular space and glenoid fossa of the temporomandibular joint, adjacent to the apex of the ear canal and glenoid fossa of the temporomandibular joint, and in the postauricular subcutaneous area and ipsilateral parotid nodes, respectively. Marginal misses should be recognized to improve target delineation. When treating SCC of the EAC and middle ear, care should be taken to cover the glenoid fossa of the temporomandibular joint and periauricular soft tissue. Elective ipsilateral parotid irradiation should be considered. The treatment planning procedure should also be refined to balance subcutaneous soft-tissue dosimetry and toxicity. Copyright © 2012 Elsevier Inc. All rights reserved.

Surgical and Technical Modalities for Hearing Restoration in Ear Malformations.

PubMed

Dazert, Stefan; Thomas, Jan Peter; Volkenstein, Stefan

2015-12-01

Malformations of the external and middle ear often go along with an aesthetic and functional handicap. Independent of additional aesthetic procedures, a successful functional hearing restoration leads to a tremendous gain in quality of life for affected patients. The introduction of implantable hearing systems (bone conduction and middle ear devices) offers new therapeutic options in this field. We focus on functional rehabilitation of patients with malformations, either by surgical reconstruction or the use of different implantable hearing devices, depending on the disease itself and the severity of malformation as well as hearing impairment. Patients with an open ear canal and minor malformations are good candidates for surgical hearing restoration of middle ear structures with passive titanium or autologous implants. In cases with complete fibrous or bony atresia of the ear canal, the most promising functional outcome and gain in quality of life can be expected with an active middle ear implant or a bone conduction device combined with a surgical aesthetic rehabilitation in a single or multi-step procedure. Although the surgical procedure for bone conduction devices is straightforward and safe, more sophisticated operations for active middle ear implants (e.g., Vibrant Soundbridge, MED-EL, Innsbruck, Austria) provide an improved speech discrimination in noise and the ability of sound localization compared with bone conduction devices where the stimulation reaches both cochleae. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Use of oral fluralaner for the treatment of Psoroptes cuniculi in 15 naturally infested rabbits.

PubMed

Sheinberg, Galia; Romero, Camilo; Heredia, Rafael; Capulin, Miguel; Yarto, Enrique; Carpio, Juan

2017-08-01

Psoroptes cuniculi, a nonburrowing ear mite, is a common ectoparasite of rabbits. Constant irritation of the auditory canal by the presence of this mite can lead to otitis externa or otoacariasis. The goal of this study was to evaluate the effect of fluralaner on rabbits naturally infested with P. cuniculi and exhibiting clinical signs. Fifteen female New Zealand domestic rabbits with otitis due to naturally occurring infestation with P. cuniculi. The external ears and ear canals of each individual were examined; samples of otic exudate were extracted with cotton swabs and examined microscopically for identification of the ectoparasite. Each animal was treated with a single 25 mg/kg oral dose of fluralaner. The amount of otic exudate/cerumen was assessed and samples were obtained from the ears to evaluate for presence or absence of mites at 4, 8, 12, 16, 20, 40 and 90 days after receiving treatment. Post-treatment, the amount of otic exudate decreased rapidly in all animals; by Day 12 and until the end of the study all rabbits were judged to have low amount of exudate with normally visible canals. The percentage of ears positive for P. cuniculi decreased to 13.3% of ears sampled by Day 4, and by Day 12 all rabbits were negative for the parasite. Administration of a single oral dose of fluralaner was effective for the treatment of naturally occurring P. cuniculi infestation in rabbits during a 90 day period. © 2017 ESVD and ACVD.

Insecticidal activity of common reagents for insect foreign bodies of the ear.

PubMed

Antonelli, P J; Ahmadi, A; Prevatt, A

2001-01-01

Insects commonly present as painful and distressing foreign bodies of the external ear canal. Removing live insects can be challenging, especially for primary care physicians who have limited equipment. The purpose of this study is to compare the insecticidal activity of commonly available preparations for insects that are most frequently recovered from ear canals: cockroaches (German and American), ticks, beetles, and honeybees. Prospective, blinded. One hundred seventy insects of each species were placed in test tubes and submerged in 17 test preparations (10 tubes per preparation, 1 insect per test tube). Insect activity was stimulated by agitation of the test tube. Responses were monitored, and the time until death was measured. Most test preparations exhibited some insecticidal activity against most insect species. Ticks were completely resistant to all of the test reagents. Ethanol killed the American cockroaches (mean time, 32.6 s), German cockroaches (mean time, 29.6 s), and honeybees (mean time, 19.6 s) the most rapidly. Many commonly available reagents may be used to kill or immobilize insect foreign bodies of the ear.

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

PubMed

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.

Systems and methods for biometric identification using the acoustic properties of the ear canal

DOEpatents

Bouchard, Ann Marie; Osbourn, Gordon Cecil

1998-01-01

The present invention teaches systems and methods for verifying or recognizing a person's identity based on measurements of the acoustic response of the individual's ear canal. The system comprises an acoustic emission device, which emits an acoustic source signal s(t), designated by a computer, into the ear canal of an individual, and an acoustic response detection device, which detects the acoustic response signal f(t). A computer digitizes the response (detected) signal f(t) and stores the data. Computer-implemented algorithms analyze the response signal f(t) to produce ear-canal feature data. The ear-canal feature data obtained during enrollment is stored on the computer, or some other recording medium, to compare the enrollment data with ear-canal feature data produced in a subsequent access attempt, to determine if the individual has previously been enrolled. The system can also be adapted for remote access applications.

Systems and methods for biometric identification using the acoustic properties of the ear canal

DOEpatents

Bouchard, A.M.; Osbourn, G.C.

1998-07-28

The present invention teaches systems and methods for verifying or recognizing a person`s identity based on measurements of the acoustic response of the individual`s ear canal. The system comprises an acoustic emission device, which emits an acoustic source signal s(t), designated by a computer, into the ear canal of an individual, and an acoustic response detection device, which detects the acoustic response signal f(t). A computer digitizes the response (detected) signal f(t) and stores the data. Computer-implemented algorithms analyze the response signal f(t) to produce ear-canal feature data. The ear-canal feature data obtained during enrollment is stored on the computer, or some other recording medium, to compare the enrollment data with ear-canal feature data produced in a subsequent access attempt, to determine if the individual has previously been enrolled. The system can also be adapted for remote access applications. 5 figs.

[Computerized study of perioperative difficulties of stapedectomy].

PubMed

Cadavid Zink, R; Ballivian, H; Gamboa, F J; Olaizola, F

1993-01-01

A retrospective study of 1035 stapedectomies was performed to assess the incidence of intraoperative complications between 1972-1990. We found 45.89% of complications. We divided this alterations in 6 groups: 1) hemorrhage (20.67%), 2) stapes, foot plate, oval window (8.40%), 3) alterations in the middle ear (6.85%), 4) alterations in the incus (3.76%), 5) alterations in the external ear canal (3.57%) and 6) problems with protesis or graf (2.60%). We have analyzed these complications. We propose to carry out the solutions.

Distortion product otoacoustic emissions upon ear canal pressurization.

PubMed

Zebian, Makram; Schirkonyer, Volker; Hensel, Johannes; Vollbort, Sven; Fedtke, Thomas; Janssen, Thomas

2013-04-01

The purpose of this study was to quantify the change in distortion product otoacoustic emission (DPOAE) level upon ear canal pressurization. DPOAEs were measured on 12 normal-hearing human subjects for ear canal static pressures between -200 and +200 daPa in (50 ± 5) daPa steps. A clear dependence of DPOAE levels on the pressure was observed, with levels being highest at the maximum compliance of the middle ear, and decreasing on average by 2.3 dB per 50 daPa for lower and higher pressures. Ear canal pressurization can serve as a tool for improving the detectability of DPOAEs in the case of middle-ear dysfunction.

Prevention of meatal stenosis in conchal setback otoplasty.

PubMed

Small, A

1975-10-01

The conchal setback is a useful technique for correcting many prominent ear deformities. A disadvantage of the technique in some cases is meatal stenosis of the external auditory canal. By excising a portion of meatal cartilage, this problem is prevented. The technique is illustrated and post-operative result is shown.

Management of Irradiated and Contaminated Casualty Victims

DTIC Science & Technology

1984-08-01

such as those that appear to be "dirty," should have the contamination brushed away or wiped away. At this point the patient should be surveyed for...contamination. Hair should be shampooed with a mild shampoo . Should contamination be present within the external ear canals, the nose, or the mouth, these

Hernia of the tympanic membrane.

PubMed

Ikeda, Ryoukichi; Miyazaki, Hiromitsu; Kawase, Tetsuaki; Katori, Yukio; Kobayashi, Toshimitsu

2017-02-01

Although tympanic bulging is commonly encountered, tympanic herniation occupying the external auditory canal is extremely rare. A 66-year-old man was presented to our hospital with left aural fullness, bilateral hearing loss and otorrhea. Preoperative findings suggested tympanic membrane (TM) hernia located in the left external auditory canal. We performed total resection of the soft mass by a transcanal approach using endoscopy. Ventilation tubes were inserted into bilateral ears. Histopathological findings confirmed diagnosis of TM hernia. Passive opening pressure of this patient was higher than normal condition of the Eustachian tube, where active opening was not observed. Hernia of the TM most likely resulted from long-term excessive Valsalva maneuver. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Theory of forward and reverse middle-ear transmission applied to otoacoustic emissions in infant and adult ears

PubMed Central

Keefe, Douglas H.; Abdala, Carolina

2008-01-01

The purpose of this study is to understand why otoacoustic emission (OAE) levels are higher in normal-hearing human infants relative to adults. In a previous study, distortion product (DP) OAE input/output (I/O) functions were shown to differ at f2=6 kHz in adults compared to infants through 6 months of age. These DPOAE I/O functions were used to noninvasively assess immaturities in forward/reverse transmission through the ear canal and middle ear [Abdala, C., and Keefe, D. H., (2006). J. Acoust Soc. Am. 120, 3832–3842]. In the present study, ear-canal reflectance and DPOAEs measured in the same ears were analyzed using a scattering-matrix model of forward and reverse transmission in the ear canal, middle ear, and cochlea. Reflectance measurements were sensitive to frequency-dependent effects of ear-canal and middle-ear transmission that differed across OAE type and subject age. Results indicated that DPOAE levels were larger in infants mainly because the reverse middle-ear transmittance level varied with ear-canal area, which differed by more than a factor of 7 between term infants and adults. The forward middle-ear transmittance level was −16 dB less in infants, so that the conductive efficiency was poorer in infants than adults. PMID:17348521

Efficacy of naturopathic extracts in the management of ear pain associated with acute otitis media.

PubMed

Sarrell, E M; Mandelberg, A; Cohen, H A

2001-07-01

To determine the efficacy and tolerance of Otikon Otic Solution (Healthy-On Ltd, Petach-Tikva, Israel), a naturopathic herbal extract (containing Allium sativum, Verbascum thapsus, Calendula flores, and Hypericum perforatum in olive oil), compared with Anaesthetic (Vitamed Pharmaceutical Ltd, Benyamina, Israel) ear drops (containing ametocaine and phenazone in glycerin) in the management of ear pain associated with acute otitis media (AOM). Children between the ages of 6 and 18 years who experienced ear pain (otalgia) and who were diagnosed with eardrum problems associated with AOM were randomly assigned to be treated with Otikon or Anaesthetic ear drops, which were instilled into the external canal(s) of the affected ear(s). Ear pain was assessed using 2 visual analog scales: a linear scale and a color scale. Pain assessment took place throughout the course of 3 days. The mean score of pain reduction was used to measure outcome. Primary pediatric community ambulatory centers. One hundred three children aged 6 to 18 years who were diagnosed with otalgia associated with AOM. Each of the 2 treatment groups were comparable on the basis of age, sex, laterality of AOM, and the effectiveness of ameliorating symptoms of otalgia. The 2 groups were also comparable to each other in the initial ear pain score and in the scores at each application of Otikon or Anaesthetic drops. There was a statistically significant improvement in ear pain score throughout the course of the study period (P =.007). Otikon, an ear drop formulation of naturopathic origin, is as effective as Anaesthetic ear drops and was proven appropriate for the management of AOM-associated ear pain.

Procedures for ambient-pressure and tympanometric tests of aural acoustic reflectance and admittance in human infants and adults

PubMed Central

Keefe, Douglas H.; Hunter, Lisa L.; Feeney, M. Patrick; Fitzpatrick, Denis F.

2015-01-01

Procedures are described to measure acoustic reflectance and admittance in human adult and infant ears at frequencies from 0.2 to 8 kHz. Transfer functions were measured at ambient pressure in the ear canal, and as down- or up-swept tympanograms. Acoustically estimated ear-canal area was used to calculate ear reflectance, which was parameterized by absorbance and group delay over all frequencies (and pressures), with substantial data reduction for tympanograms. Admittance measured at the probe tip in adults was transformed into an equivalent admittance at the eardrum using a transmission-line model for an ear canal with specified area and ear-canal length. Ear-canal length was estimated from group delay around the frequency above 2 kHz of minimum absorbance. Illustrative measurements in ears with normal function are described for an adult, and two infants at 1 month of age with normal hearing and a conductive hearing loss. The sensitivity of this equivalent eardrum admittance was calculated for varying estimates of area and length. Infant-ear patterns of absorbance peaks aligned in frequency with dips in group delay were explained by a model of resonant canal-wall mobility. Procedures will be applied in a large study of wideband clinical diagnosis and monitoring of middle-ear and cochlear function. PMID:26723319

21 CFR 524.1195 - Ivermectin otic suspension.

Code of Federal Regulations, 2011 CFR

2011-04-01

....1195 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Ivermectin otic suspension. (a) Specifications. Each tube contains 0.5 milliliter (mL) of a 0.01 percent...—(1) Amount. Administer the contents of one 0.5-mL tube topically into each external ear canal. (2...

21 CFR 524.1195 - Ivermectin otic suspension.

Code of Federal Regulations, 2010 CFR

2010-04-01

....1195 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Ivermectin otic suspension. (a) Specifications. Each tube contains 0.5 milliliter (mL) of a 0.01 percent...—(1) Amount. Administer the contents of one 0.5-mL tube topically into each external ear canal. (2...

Krazy Glue® in the ear: A case report of child abuse.

PubMed

Sorichetti, Brendan D; Fandiño, Marcela; Kozak, Frederick K

2018-06-01

Krazy Glue ® or cyanoacrylate glue is an acrylic resin that polymerizes in less than a minute when in contact with moisture or water. We present a case of a one month old referred to our tertiary pediatric otolaryngology clinic from an outside emergency department with a history of application of cyanoacrylate glue in the external ear canals. This report presents the management of this case along with the medical and legal outcomes surrounding this case of child abuse. Copyright © 2018. Published by Elsevier B.V.

Type II first branchial cleft anomaly.

PubMed

Al-Mahdi, Akmam H; Al-Khurri, Luay E; Atto, Ghada Z; Dhaher, Ameer

2013-01-01

First branchial cleft anomaly is a rare disease of the head and neck. It accounts for less than 8% of all branchial abnormalities. It is classified into type I, which is thought to arise from the duplication of the membranous external ear canal and are composed of ectoderm only, and type II that have ectoderm and mesoderm. Because of its rarity, first branchial cleft anomaly is often misdiagnosed and results in inappropriate management. A 9-year-old girl presented to us with fistula in the submandibular region and discharge in the external ear. Under general anesthesia, complete surgical excision of the fistula tract was done through step-ladder approach, and the histopathologic examination confirmed the diagnosis of type II first branchial cleft anomaly.

Prevalence of Semicircular Canal Hypoplasia in Patients With CHARGE Syndrome: 3C Syndrome.

PubMed

Wineland, Andre; Menezes, Maithilee D; Shimony, Joshua S; Shinawi, Marwan S; Hullar, Timothy E; Hirose, Keiko

2017-02-01

CHARGE syndrome refers to a syndrome involving coloboma, heart defects, atresia choanae, retardation of growth and development, genitourinary disorders, and ear anomalies. However, Verloes revised the characteristics of CHARGE syndrome in 2005 to define this syndrome more broadly. Deficiency of the semicircular canals is now a major criterion for CHARGE syndrome. To characterize patients with CHARGE syndrome at our center using Verloes' criteria and to reevaluate the nomenclature for this condition. We performed a medical chart review of patients with CHARGE syndrome and reviewed their temporal bone imaging studies at a tertiary care children's hospital affiliated with Washington University in St Louis. Two authors independently reviewed each imaging study (A.W. and K.H.). Radiologic studies, physical findings, genetic tests, and other diagnostic tests were included. Patients with no temporal bone imaging studies were excluded. Eighteen children were included in this study; 13 children (72%) were male, and the mean (median; range) age of patients at the time of inner ear imaging studies was 2 years (4.5 years; 8 months to 8 years). Coloboma was present in 13 patients (72%) and choanal atresia in 5 (28%); semicircular canal anomalies were present in all patients. Additionally, 13 patients (72%) were diagnosed as having hindbrain anomalies, 17 (94%) as having endocrine disorders, 17 (94%) as having mediastinal organ malformations, and all as having middle or external ear abnormalities and development delay. Cleft lip and cleft palate were found in 6 of 14 patients (43%) who did not have choanal atresia. We tested 16 patients for mutations in the CHD7 gene; 10 were positive (63%) for mutations, 4 (25%) were negative, and 2 (13%) were inconclusive. Semicircular canal anomalies were the most consistent finding in our patients with CHARGE syndrome. Given the high prevalence of semicircular canal hypoplasia and importance of imaging for diagnosing CHARGE syndrome, we propose changing the term CHARGE syndrome to 3C syndrome to emphasize the importance of the semicircular canals and to recall the 3 major criteria for diagnosis: coloboma, choanal atresia, and semicircular canal anomaly. The nomenclature would also reference the 3 semicircular canals in each ear. This new name for CHARGE syndrome would provide a mnemonic and focus the disease on the most important clinical criteria for diagnosis.

Sound pressure distribution and power flow within the gerbil ear canal from 100 Hz to 80 kHz

PubMed Central

Ravicz, Michael E.; Olson, Elizabeth S.; Rosowski, John J.

2008-01-01

Sound pressure was mapped in the bony ear canal of gerbils during closed-field sound stimulation at frequencies from 0.1 to 80 kHz. A 1.27-mm-diam probe-tube microphone or a 0.17-mm-diam fiber-optic miniature microphone was positioned along approximately longitudinal trajectories within the 2.3-mm-diam ear canal. Substantial spatial variations in sound pressure, sharp minima in magnitude, and half-cycle phase changes occurred at frequencies >30 kHz. The sound frequencies of these transitions increased with decreasing distance from the tympanic membrane (TM). Sound pressure measured orthogonally across the surface of the TM showed only small variations at frequencies below 60 kHz. Hence, the ear canal sound field can be described fairly well as a one-dimensional standing wave pattern. Ear-canal power reflectance estimated from longitudinal spatial variations was roughly constant at 0.2–0.5 at frequencies between 30 and 45 kHz. In contrast, reflectance increased at higher frequencies to at least 0.8 above 60 kHz. Sound pressure was also mapped in a microphone-terminated uniform tube—an “artificial ear.” Comparison with ear canal sound fields suggests that an artificial ear or “artificial cavity calibration” technique may underestimate the in situ sound pressure by 5–15 dB between 40 and 60 kHz. PMID:17902852

Self-demodulation of amplitude-modulated signal components in amplitude-modulated bone-conducted ultrasonic hearing

NASA Astrophysics Data System (ADS)

Ito, Kazuhito; Nakagawa, Seiji

2015-07-01

A novel hearing aid system utilizing amplitude-modulated bone-conducted ultrasound (AM-BCU) is being developed for use by profoundly deaf people. However, there is a lack of research on the acoustic aspects of AM-BCU hearing. In this study, acoustic fields in the ear canal under AM-BCU stimulation were examined with respect to the self-demodulation effect of amplitude-modulated signal components generated in the ear canal. We found self-demodulated signals with an audible sound pressure level related to the amplitude-modulated signal components of bone-conducted ultrasonic stimulation. In addition, the increases in the self-demodulated signal levels at low frequencies in the ear canal after occluding the ear canal opening, i.e., the positive occlusion effect, indicate the existence of a pathway by which the self-demodulated signals pass through the aural cartilage and soft tissue, and radiate into the ear canal.

Chinchilla middle-ear admittance and sound power: High-frequency estimates and effects of inner-ear modifications

PubMed Central

Ravicz, Michael E.; Rosowski, John J.

2012-01-01

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 YTM, the ME input admittance at the TM, from the admittance measured relatively far from the TM. YTM appears valid at frequencies as high as 17 kHz, a much higher frequency than previously reported. The real part of YTM 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. PMID:23039439

Canal wall reconstruction and preservation in the surgical management of cholesteatoma in children with Down's syndrome.

PubMed

Nash, Robert; Possamai, Victoria; Maskell, Scott; Bailey, Martin; Albert, David

2014-10-01

Down's syndrome is associated with poor Eustachian tube function, and an increased incidence of cholesteatoma. The only previously published case series suggests that 'canal wall preserving' procedures are only rarely suitable for the management of cholesteatoma in this population. We conducted a retrospective review of the hospital's clinical records database to identify patients with Down's syndrome and cholesteatoma. These patients' notes were then reviewed. We identified nine patients with Down's syndrome who had undergone surgical management of cholesteatoma over a twelve year period. Three patients had bilateral disease, meaning twelve ears were treated. Seven ears were initially treated with 'canal wall down' procedures. Four out of five of the remaining ears were successfully treated using 'canal wall preservation' or 'canal wall reconstruction', with one ear requiring subsequent conversion to a 'canal wall down' approach. Canal wall preservation/reconstruction is feasible in patients with Down's syndrome, even when cholesteatoma extends into the mastoid. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Comparison of nine methods to estimate ear-canal stimulus levels

PubMed Central

Souza, Natalie N.; Dhar, Sumitrajit; Neely, Stephen T.; Siegel, Jonathan H.

2014-01-01

The reliability of nine measures of the stimulus level in the human ear canal was compared by measuring the sensitivity of behavioral hearing thresholds to changes in the depth of insertion of an otoacoustic emission probe. Four measures were the ear-canal pressure, the eardrum pressure estimated from it and the pressure measured in an ear simulator with and without compensation for insertion depth. The remaining five quantities were derived from the ear-canal pressure and the Thévenin-equivalent source characteristics of the probe: Forward pressure, initial forward pressure, the pressure transmitted into the middle ear, eardrum sound pressure estimated by summing the magnitudes of the forward and reverse pressure (integrated pressure) and absorbed power. Two sets of behavioral thresholds were measured in 26 subjects from 0.125 to 20 kHz, with the probe inserted at relatively deep and shallow positions in the ear canal. The greatest dependence on insertion depth was for transmitted pressure and absorbed power. The measures with the least dependence on insertion depth throughout the frequency range (best performance) included the depth-compensated simulator, eardrum, forward, and integrated pressures. Among these, forward pressure is advantageous because it quantifies stimulus phase. PMID:25324079

Duplication of the External Auditory Canal: Two Cases and a Review of the Literature

PubMed Central

Goudakos, John K.; Blioskas, Sarantis; Psillas, George; Vital, Victor; Markou, Konstantinos

2012-01-01

The objective of the present paper is to describe the clinical presentation, diagnostic process, surgical treatment, and outcome of 2 patients with first branchial cleft anomaly. The first case was an 8-year-old girl presented with an elastic lesion located in the left infra-auricular area, in close relation with the lobule, duplicating the external auditory canal. The magnetic resonance imaging revealed a lesion, appearing as a rather well-circumscribed mass within the left parotid gland and duplicating the ear canal. A superficial parotidectomy was subsequently performed, with total excision of the cyst. The second patient was a 15-year-old girl presented with a congenital fistula of the right lateral neck. At superficial parotidectomy, a total excision of the fistula was performed. During the operation the tract was recorded to lay between the branches of the facial nerve, extending with a blind ending canal parallel to the external acoustic meatus. Conclusively, first branchial cleft anomalies are rare malformations with cervical, parotid, or auricular clinical manifestations. Diagnosis of first branchial cleft lesions is achieved mainly through careful physical examination. Complete surgical excision with wide exposure of the lesion is essential in order to achieve permanent cure and avoid recurrence. PMID:23213587

A miniaturized laser-Doppler-system in the ear canal

NASA Astrophysics Data System (ADS)

Schmidt, T.; Gerhardt, U.; Kupper, C.; Manske, E.; Witte, H.

2013-03-01

Gathering vibrational data from the human middle ear is quite difficult. To this date the well-known acoustic probe is used to estimate audiometric parameters, e.g. otoacoustic emissions, wideband reflectance and the measurement of the stapedius reflex. An acoustic probe contains at least one microphone and one loudspeaker. The acoustic parameter determination of the ear canal is essential for the comparability of test-retest measurement situations. Compared to acoustic tubes, the ear canal wall cannot be described as a sound hard boundary. Sound energy is partly absorbed by the ear canal wall. In addition the ear canal features a complex geometric shape (Stinson and Lawton1). Those conditions are one reason for the inter individual variability in input impedance measurement data of the tympanic membrane. The method of Laser-Doppler-Vibrometry is well described in literature. Using this method, the surface velocity of vibrating bodies can be determined contact-free. Conventional Laser-Doppler-Systems (LDS) for auditory research are mounted on a surgical microscope. Assuming a free line of view to the ear drum, the handling of those laser-systems is complicated. We introduce the concept of a miniaturized vibrometer which is supposed to be applied directly in the ear canal for contact-free measurement of the tympanic membrane surface vibration. The proposed interferometer is based on a Fabry-Perot etalon with a DFB laser diode as light source. The fiber-based Fabry-Perot-interferometer is characterized by a reduced size, compared to e.g. Michelson-, or Mach-Zehnder-Systems. For the determination of the phase difference in the interferometer, a phase generated carrier was used. To fit the sensor head in the ear canal, the required shape of the probe was generated by means of the geometrical data of 70 ear molds. The suggested prototype is built up by a singlemode optical fiber with a GRIN-lens, acting as a fiber collimator. The probe has a diameter of 1.8 mm and a length of 5 mm.

Factors that introduce intrasubject variability into ear-canal absorbance measurements.

PubMed

Voss, Susan E; Stenfelt, Stefan; Neely, Stephen T; Rosowski, John J

2013-07-01

Wideband immittance measures can be useful in analyzing acoustic sound flow through the ear and also have diagnostic potential for the identification of conductive hearing loss as well as causes of conductive hearing loss. To interpret individual measurements, the variability in test–retest data must be described and quantified. Contributors to variability in ear-canal absorbance–based measurements are described in this article. These include assumptions related to methodologies and issues related to the probe fit within the ear and potential acoustic leaks. Evidence suggests that variations in ear-canal cross-sectional area or measurement location are small relative to variability within a population. Data are shown to suggest that the determination of the Thévenin equivalent of the ER-10C probe introduces minimal variability and is independent of the foam ear tip itself. It is suggested that acoustic leaks in the coupling of the ear tip to the ear canal lead to substantial variations and that this issue needs further work in terms of potential criteria to identify an acoustic leak. In addition, test–retest data from the literature are reviewed.

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

PubMed

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.

Biomechanical Modeling and Measurement of Blast Injury and Hearing Protection Mechanisms

DTIC Science & Technology

2015-10-01

12 software into Workbench V. 15 in CFX/ANSYS; 2) building the geometry of the ear model with ossicular chain and cochlear load in CFX; 3...the ear canal to middle ear. The model consists of the ear canal, TM, middle ear ossicles and suspensory ligaments, middle ear cavity, and cochlear ...the TM, ossicles, and ligaments/muscle tendons with the cochlear load applied on the stapes footplate. 17 Fig. 21. Time-history plots of

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

PubMed

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.

Pressure transfer function and absorption cross section from the diffuse field to the human infant ear canal.

PubMed

Keefe, D H; Bulen, J C; Campbell, S L; Burns, E M

1994-01-01

The diffuse-field pressure transfer function from a reverberant field to the ear canal of human infants, ages 1, 3, 6, 12, and 24 months, has been measured from 125-10700 Hz. The source was a loudspeaker using pink noise, and the diffuse-field pressure and the ear-canal pressure were simultaneously measured using a spatial averaging technique in a reverberant room. The results in most subjects show a two-peak structure in the 2-6-kHz range, corresponding to the ear-canal and concha resonances. The ear-canal resonance frequency decreases from 4.4 kHz at age 1 month to 2.9 kHz at age 24 months. The concha resonance frequency decreases from 5.5 kHz at age 1 month to 4.5 kHz at age 24 months. Below 2 kHz, the diffuse-field transfer function shows effects due to the torsos of the infant and parent, and varies with how the infant is held. Comparisons are reported of the diffuse-field absorption cross section for infants relative to adults. This quantity is a measure of power absorbed by the middle ear from a diffuse sound field, and large differences are observed in infants relative to adults. The radiation efficiencies of the infant and the adult ear are small at low frequencies, near unity at midfrequencies, and decrease at higher frequencies. The process of ear-canal development is not yet complete at age 24 months. The results have implications for experiments on hearing in infants.

[2000-year history of the ear syringe and its relationship to the enema. Images from the history of otorhinolaryngology, represented by instruments from the collection of the Ingolstadt Medical History Museum].

PubMed

Feldmann, H

1999-08-01

SYRINGES WITH A PISTON AND THEIR USE AS "CLYSTER ORICULARIUS" IN THE ANCIENT ROME: Syringes with a piston were already known in ancient times and have been mentioned as a device for spraying rose water (Philon of Byzantium, about 230 BC), and for fighting fires (Heron of Alexandria about 110 AD). Celsus mentions it several times in his grand opus "De Medicina" (1st century AD) in the treatment of purulent discharge from the ear and for removing foreign bodies from the external ear canal. He always calls it "clyster oricularius", i.e. ear syringe, even when he describes its use in applications other than otological, such as in urology. Later the ear syringe fell from favor for a very long time and was reinvented only at the beginning of the 19th century. IRRIGATION OF THE BOWELS, FROM THE BAG SYRINGE TO THE PISTON SYRINGE: Irrigations of the bowels, clysters, were performed from ancient times to the 18th century with a baglike syringe using the bladder of animals as a pouch. Syringes with a piston were used by barbers and surgeons only for cleansing wounds or irrigating natural cavities of the body. Irrigation of the external ear canal had completely fallen from favor. In France in the 18th century large syringes with a piston made of tin oder brass came into use for enemas and replaced the old baglike devices. THE REINVENTION OF THE EAR SYRINGE AFTER THE PROTOTYPE OF THE ENEMA SYRINGE: Itard, an otologist in France in 1821, was the first to describe irrigating the ear with a syringe to remove hard wax. He recommended using an enema syringe ("seringue à lavement") for the procedure. Soon after his publication special ear syringes of appropriate size were developed and described by Beck in Freiburg, Germany, in 1827; by Fabrizi in Modena, Italy, 1839; and Schmalz in Dresden, Germany, 1846, who also introduced the kidney-shaped bowel for catching the water. Apart from that, small baglike syringes made of rubber were devised especially for use by the patient himself (Kramer, Berlin, 1860). This historical development is described in detail and illustrated by numerous figures.

Cold atmospheric plasma for local infection control and subsequent pain reduction in a patient with chronic post-operative ear infection

PubMed Central

Isbary, G; Shimizu, T; Zimmermann, J L; Thomas, H M; Morfill, G E; Stolz, W

2013-01-01

Following surgery of cholesteatoma, a patient developed a chronic infection of the external auditory canal, including extended-spectrum β-lactamase producing Escherichia coli, which caused severe pain. The application of cold atmospheric plasma resulted in a significant reduction in pain and clearance of bacterial carriage, allowing antibiotics and analgesics to be ceased. PMID:25356328

A case of direct intracranial extension of tuberculous otitis media.

PubMed

Kim, Dong-Kee; Park, Shi-Nae; Park, Kyung-Ho; Yeo, Sang Won

2014-02-01

We describe a very rare case of tuberculous otitis media (TOM) with direct intracranial extension. The patient was a 55-year-old man who presented to our ENT clinic for evaluation of severe headaches and right-sided otorrhea. A biopsy of granulation tissue obtained from the right external auditory canal demonstrated chronic inflammation that was suggestive of mycobacterial infection. Magnetic resonance imaging of the brain indicated intracranial extension of TOM through a destroyed tegmen mastoideum. After 2 months of antituberculous medication, the headaches and otorrhea were controlled, and the swelling in the external ear canal subsided greatly. Rarely does TOM spread intracranially. In most such cases, intracranial extension of tuberculosis occurs as the result of hematogenous or lymphogenous spread. In rare cases, direct spread through destroyed bone can occur, as it did in our patient.

Finite element modeling of sound transmission with perforations of tympanic membrane

PubMed Central

Gan, Rong Z.; Cheng, Tao; Dai, Chenkai; Yang, Fan; Wood, Mark W.

2009-01-01

A three-dimensional finite element (FE) model of human ear with structures of the external ear canal, middle ear, and cochlea has been developed recently. In this paper, the FE model was used to predict the effect of tympanic membrane (TM) perforations on sound transmission through the middle ear. Two perforations were made in the posterior-inferior quadrant and inferior site of the TM in the model with areas of 1.33 and 0.82 mm2, respectively. These perforations were also created in human temporal bones with the same size and location. The vibrations of the TM (umbo) and stapes footplate were calculated from the model and measured from the temporal bones using laser Doppler vibrometers. The sound pressure in the middle ear cavity was derived from the model and measured from the bones. The results demonstrate that the TM perforations can be simulated in the FE model with geometrical visualization. The FE model provides reasonable predictions on effects of perforation size and location on middle ear transfer function. The middle ear structure-function relationship can be revealed with multi-field coupled FE analysis. PMID:19603881

KGFR as a possible therapeutic target in middle ear cholesteatoma.

PubMed

Yamamoto-Fukuda, Tomomi; Akiyama, Naotaro; Shibata, Yasuaki; Takahashi, Haruo; Ikeda, Tohru; Kohno, Michiaki; Koji, Takehiko

2014-11-01

We demonstrated that repression of keratinocyte growth factor (KGF) receptor (KGFR) could be a potentially useful strategy in the conservative treatment of middle ear cholesteatoma. Recently, the use of a selective inhibitor of the KGFR, SU5402, in an in vitro experiment resulted in the inhibition of the differentiation and proliferation of epithelial cells through KGF secretion by fibroblasts isolated from the cholesteatoma. In this study, we investigated the effects of the KGFR inhibitor during middle ear cholesteatoma formation in vivo. Based on the role of KGF in the development of cholesteatoma, Flag-hKGF cDNA driven by CMV14 promoter was transfected through electroporation into the external auditory canal of rats five times on every fourth day. Ears transfected with empty vector were used as controls. KGFR selective inhibitor (SU5402) or MEK inhibitor (PD0325901) was administered in the right ear of five rats after vector transfection. In the control, 2% DMSO in PBS was administered in the other ears after vector transfection. The use of a selective KGFR inhibitor, SU5402, completely prevented middle ear cholesteatoma formation in the rats.

A new method for selecting auricle positions in skull base reconstruction for temporal bone cancer.

PubMed

Tanaka, Kentaro; Yano, Tomoyuki; Homma, Tsutomu; Tsunoda, Atsunobu; Aoyagi, Masaru; Kishimoto, Seiji; Okazaki, Mutsumi

2018-03-25

In advanced temporal bone carcinoma cases, we attempted to preserve as much of the auricle as possible from a cosmetic and functional perspective. Difficulties are associated with selecting an adequate position for reconstructed auricles intraoperatively. We improved the surgical procedure to achieve a good postoperative auricle position. Nine patients were included in this study. All patients underwent subtotal removal of the temporal bone and resection of the external auditory canal while preserving most of the external ear, and lateral skull base reconstruction was performed with anterolateral thigh flaps. We invented a new device, the auricle localizer, to select the correct position for the replaced external ear. The head skin incision line and two points of three-point pin fixation were used as criteria, and a Kirschner wire was shaped as a basic line to match these criteria. Another Kirschner wire was shaped by wrapping it around the inferior edge of the external ear as the positioning line, and these two lines were then combined. To evaluate the postoperative auricle position, the auricle inclination angle was measured using head frontal cephalogram imaging. The external ear on the affected side clearly drooped postoperatively in nonlocalizer cases, whereas this was not obvious in localizer cases. Auricle inclination angles 1 year after surgery significantly differed between these two cases (P = 0.018). The surgical device, the auricle localizer, is useful for selecting intraoperative accurate auricle positions. The assessment index, the auricle inclination angle, is useful for quantitatively evaluating postoperative results. 4 Laryngoscope, 2018. © 2018 The American Laryngological, Rhinological and Otological Society, Inc.

Prevention and management of vascular complications in middle ear and cochlear implant surgery.

PubMed

Di Lella, Filippo; Falcioni, Maurizio; Piccinini, Silvia; Iaccarino, Ilaria; Bacciu, Andrea; Pasanisi, Enrico; Cerasti, Davide; Vincenti, Vincenzo

2017-11-01

The objective of this study is to illustrate prevention strategies and management of vascular complications from the jugular bulb (JB) and internal carotid artery (ICA) during middle ear surgery or cochlear implantation. The study design is retrospective case series. The setting is tertiary referral university hospital. Patients were included if presented pre- or intraoperative evidence of high-risk anatomical anomalies of ICA or JB during middle ear or cochlear implant surgery, intraoperative vascular injury, or revision surgery after the previous iatrogenic vascular lesions. The main outcome measures are surgical outcomes and complications rate. Ten subjects were identified: three underwent cochlear implant surgery and seven underwent middle ear surgery. Among the cochlear implant patients, two presented with anomalies of the JB impeding access to the cochlear lumen and one underwent revision surgery for incorrect positioning of the array in the carotid canal. Subtotal petrosectomy was performed in all cases. Anomalies of the JB were preoperatively identified in two patients with attic and external auditory canal cholesteatoma, respectively. In a patient, a high and dehiscent JB was found during myringoplasty, while another underwent revision surgery after iatrogenic injury of the JB. A dehiscent ICA complicated middle ear effusion in one case, while in another case, a carotid aneurysm determined a cholesterol granuloma. Rupture of a pseudoaneurysm of the ICA occurred in a child during second-stage surgery and required permanent balloon occlusion without neurological complications. Knowledge of normal anatomy and its variants and preoperative imaging are the basis for prevention of vascular complications during middle ear or cochlear implant surgery.

Non-ossicular signal transmission in human middle ears: Experimental assessment of the “acoustic route” with perforated tympanic membranes

PubMed Central

Voss, Susan E.; Rosowski, John J.; Merchant, Saumil N.; Peake, William T.

2008-01-01

Direct acoustic stimulation of the cochlea by the sound-pressure difference between the oval and round windows (called the “acoustic route”) has been thought to contribute to hearing in some pathological conditions, along with the normally dominant “ossicular route.” To determine the efficacy of this acoustic route and its constituent mechanisms in human ears, sound pressures were measured at three locations in cadaveric temporal bones [with intact and perforated tympanic membranes (TMs)]: (1) in the external ear canal lateral to the TM, PTM; (2) in the tympanic cavity lateral to the oval window, POW; and (3) near the round window, PRW. Sound transmission via the acoustic route is described by two concatenated processes: (1) coupling of sound pressure from ear canal to middle-ear cavity, HPCAV≡PCAV/PTM, where PCAV represents the middle-ear cavity pressure, and (2) sound-pressure difference between the windows, HWPD≡(POW−PRW)/PCAV. Results show that: HPCAV depends on perforation size but not perforation location; HWPD depends on neither perforation size nor location. The results (1) provide a description of the window pressures based on measurements, (2) refute the common otological view that TM perforation location affects the “relative phase of the pressures at the oval and round windows,” and (3) show with an intact ossicular chain that acoustic-route transmission is substantially below ossicular-route transmission except for low frequencies with large perforations. Thus, hearing loss from TM perforations results primarily from reduction in sound coupling via the ossicular route. Some features of the frequency dependence of HPCAV and HWPD can be interpreted in terms of a structure-based lumped-element acoustic model of the perforation and middle-ear cavities. PMID:17902851

External auditory canal cholesteatoma and keratosis obturans: the role of imaging in preventing facial nerve injury.

PubMed

McCoul, Edward D; Hanson, Matthew B

2011-12-01

We conducted a retrospective study to compare the clinical characteristics of external auditory canal cholesteatoma (EACC) with those of a similar entity, keratosis obturans (KO). We also sought to identify those aspects of each disease that may lead to complications. We identified 6 patients in each group. Imaging studies were reviewed for evidence of bony erosion and the proximity of disease to vital structures. All 6 patients in the EACC group had their diagnosis confirmed by computed tomography (CT), which demonstrated widening of the bony external auditory canal; 4 of these patients had critical erosion of bone adjacent to the facial nerve. Of the 6 patients with KO, only 2 had undergone CT, and neither exhibited any significant bony erosion or expansion; 1 of them developed osteomyelitis of the temporal bone and adjacent temporomandibular joint. Another patient manifested KO as part of a dermatophytid reaction. The essential component of treatment in all cases of EACC was microscopic debridement of the ear canal. We conclude that EACC may produce significant erosion of bone with exposure of vital structures, including the facial nerve. Because of the clinical similarity of EACC to KO, misdiagnosis is possible. Temporal bone imaging should be obtained prior to attempts at debridement of suspected EACC. Increased awareness of these uncommon conditions is warranted to prompt appropriate investigation and prevent iatrogenic complications such as facial nerve injury.

Middle ear polyps: results of traction avulsion after a lateral approach to the ear canal in 62 cats (2004-2014).

PubMed

Janssens, Sara Ds; Haagsman, Annika N; Ter Haar, Gert

2017-08-01

Objectives The objective of this study was to report the surgical outcome and complication rate of deep traction avulsion (TA) of feline aural inflammatory polyps after a lateral approach (LA) to the ear canal. Methods This was a retrospective analysis of data retrieved from an electronic database of 62 cats treated with TA after an LA (TALA) for removal of ear canal polyps. Long-term outcome was assessed via a telephone questionnaire survey with the owners. Results Domestic shorthair cats (48%) and Maine Coons (37%) were over-represented. The most common presenting clinical signs were otorrhoea, ear scratching and head shaking. Video-otoscopic examination confirmed a polypous mass in the ear canal in all patients. All 62 cats underwent TALA, with a mean surgical time of 33 mins for experienced surgeons (n = 4) and 48 mins (n = 12) for less experienced surgeons. The recurrence rate of polyp regrowth for experienced surgeons was 14.3% vs 35% for the less experienced surgeons. Postoperative complications included Horner's syndrome (11.5%) and facial nerve paralysis (3%). Otitis interna was not observed. Conclusions and relevance A lateral approach to the ear canal in combination with deep TA of an aural inflammatory polyp is an effective first-line technique that results in a low recurrence and complication rate.

Comparing otoacoustic emissions evoked by chirp transients with constant absorbed sound power and constant incident pressure magnitude.

PubMed

Keefe, Douglas H; Feeney, M Patrick; Hunter, Lisa L; Fitzpatrick, Denis F

2017-01-01

Human ear-canal properties of transient acoustic stimuli are contrasted that utilize measured ear-canal pressures in conjunction with measured acoustic pressure reflectance and admittance. These data are referenced to the tip of a probe snugly inserted into the ear canal. Promising procedures to calibrate across frequency include stimuli with controlled levels of incident pressure magnitude, absorbed sound power, and forward pressure magnitude. An equivalent pressure at the eardrum is calculated from these measured data using a transmission-line model of ear-canal acoustics parameterized by acoustically estimated ear-canal area at the probe tip and length between the probe tip and eardrum. Chirp stimuli with constant incident pressure magnitude and constant absorbed sound power across frequency were generated to elicit transient-evoked otoacoustic emissions (TEOAEs), which were measured in normal-hearing adult ears from 0.7 to 8 kHz. TEOAE stimuli had similar peak-to-peak equivalent sound pressure levels across calibration conditions. Frequency-domain TEOAEs were compared using signal level, signal-to-noise ratio (SNR), coherence synchrony modulus (CSM), group delay, and group spread. Time-domain TEOAEs were compared using SNR, CSM, instantaneous frequency and instantaneous bandwidth. Stimuli with constant incident pressure magnitude or constant absorbed sound power across frequency produce generally similar TEOAEs up to 8 kHz.

49 CFR 227.5 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-10-01

... doubling of the allowable exposure time to maintain the same noise dose. For purposes of this part, the... device or material, which is capable of being worn on the head, covering the ear canal or inserted in the ear canal; is designed wholly or in part to reduce the level of sound entering the ear; and has a...

49 CFR 227.5 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-10-01

... doubling of the allowable exposure time to maintain the same noise dose. For purposes of this part, the... device or material, which is capable of being worn on the head, covering the ear canal or inserted in the ear canal; is designed wholly or in part to reduce the level of sound entering the ear; and has a...

49 CFR 227.5 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-10-01

... doubling of the allowable exposure time to maintain the same noise dose. For purposes of this part, the... device or material, which is capable of being worn on the head, covering the ear canal or inserted in the ear canal; is designed wholly or in part to reduce the level of sound entering the ear; and has a...

A randomized, blinded study of canal wall up versus canal wall down mastoidectomy determining the differences in viewing middle ear anatomy and pathology.

PubMed

Hulka, G F; McElveen, J T

1998-09-01

Canal wall down and intact canal wall tympanomastoidectomy represent two surgical approaches to middle ear pathology. The authors hypothesize that there is a difference in the ability to view structures in the middle ear between these two methods. Depending on the individual, many surgeons have used the two different techniques of intact canal wall and canal wall down tympanomastoidectomy for approaching the middle ear. However, opinions conflict as to which approach provides the best visualization of different locations in the middle ear. This study prospectively evaluated temporal bones to determine the differences in visualizing structures of the middle ear using these two approaches. Twelve temporal bones underwent a standardized canal wall down tympanomastoidectomy using a reversible canal wall down technique. All bones were viewed in two dissections: intact canal wall and canal wall down preparations. Four points previously had been marked on each temporal bone in randomly assigned colors. These points include the sinus tympani, posterior crus of stapes, lateral epitympanum, and the Eustachian tube orifice. An observer blinded to the purpose of the study, color, and number of locations recorded the color and location of marks observed within the temporal bones. Randomized bones of two separate settings were viewed such that each bone was viewed in both the canal wall down and the intact canal wall preparations. A significant difference was noted in the ability to observe middle ear pathology between the intact canal wall versus canal wall down tympanomastoidectomy, with the latter showing superiority (p < 0.001). Of the four subsites, the sinus tympani, posterior crus of stapes, and lateral epitympanum were observed more frequently with the canal wall down. There was no significant difference in the ability to observe the Eustachian tube orifice between the two techniques. Statistical analysis shows good reproducibility and randomization of this study. The canal wall down tympanomastoidectomy allowed for superior viewing of the three locations, sinus tympanic, posterior crus of stapes, and lateral at the tympanum, as they were marked in the study. This study shows the potential for improved visualization via the canal wall down tympanomastoidectomy. A significant amount of literature written by individuals and otology group practices is available retrospectively comparing the advantages and disadvantages of intact canal wall versus canal wall down mastoidectomy procedures for approaching middle ear pathology. In the interest of objectively evaluating the differences between these two approaches, we have studied temporal bones in a prospective randomized, blinded study comparing the two. Twelve bones were used and observed twice, once in each of 2 sessions. All bones were viewed in two dissections: intact canal wall and canal wall down mastoidectomy. Four points were marked on each temporal bone in three different colors applied in a randomized order to eliminate observer expectation. The four points marked include sinus tympani, posterior crus of the stapes footplate, lateral epitympanum, and Eustachian tube orifice. Both intact canal wall and canal wall down bones were provided randomly to the observer at each viewing session. Before the observer was allowed to see the dissections, those requiring replacement of the canal for the first session of the study had this done in a method using native posterior bony canal. Temporal bones were presented to an expert otologist in a randomized fashion with each temporal bone being placed in a temporal bone bowl holder and specialized framework, allowing for rotation and repositioning approximating the experience in an operating room setting. For each temporal bone, the observer filled in a questionnaire describing his or her observations by denoting both location and color of marks observed. (ABSTRACT TRUNCATED)

Continuous long-term measurements of the middle ear pressure in subjects without a history of ear disease.

PubMed

Tideholm, B; Carlborg, B; Jönsson, S; Bylander-Groth, A

1998-06-01

A new method was used for continuous measurement of the middle ear (ME) pressure during a 24-h period. In 10 subjects without a history of ear disease a small perforation was made through the tympanic membrane. A tight rubber stopper containing a small polyethylene tube was fitted into the external ear canal. Conventional tubal function tests were performed. The equipment was then carried by the subjects for 24 h of normal activity to monitor any slow or rapid dynamic pressure change in the ME. Body position was found to be the most important factor affecting ME pressure variation, during the 24-h continuous pressure measurements. A significant pressure rise occurred in the recumbent position in all but one subject. Few rapid pressure equilibrations were seen during the recordings, indicating few tubal openings. This implies that the pressure changes in the ME seen in this study were mainly the result of gas exchange over the mucosa. The investigation might be a base for reference when investigating different kinds of pathologic conditions in the ear.

Direct cost comparison of totally endoscopic versus open ear surgery.

PubMed

Patel, N; Mohammadi, A; Jufas, N

2018-02-01

Totally endoscopic ear surgery is a relatively new method for managing chronic ear disease. This study aimed to test the null hypothesis that open and endoscopic approaches have similar direct costs for the management of attic cholesteatoma, from an Australian private hospital setting. A retrospective direct cost comparison of totally endoscopic ear surgery and traditional canal wall up mastoidectomy for the management of attic cholesteatoma in a private tertiary setting was undertaken. Indirect and future costs were excluded. A direct cost comparison of anaesthetic setup and resources, operative setup and resources, and surgical time was performed between the two techniques. Totally endoscopic ear surgery has a mean direct cost reduction of AUD$2978.89 per operation from the hospital perspective, when compared to canal wall up mastoidectomy. Totally endoscopic ear surgery is more cost-effective, from an Australian private hospital perspective, than canal wall up mastoidectomy for attic cholesteatoma.

Optical measurement of the weak non-linearity in the eardrum vibration response to auditory stimuli

NASA Astrophysics Data System (ADS)

Aerts, Johan

The mammalian hearing organ consists of the external ear (auricle and ear canal) followed by the middle ear (eardrum and ossicles) and the inner ear (cochlea). Its function is to convert the incoming sound waves and convert them into nerve pulses which are processed in the final stage by the brain. The main task of the external and middle ear is to concentrate the incoming sound waves on a smaller surface to reduce the loss that would normally occur in transmission from air to inner ear fluid. In the past it has been shown that this is a linear process, thus without serious distortions, for sound waves going up to pressures of 130 dB SPL (˜90 Pa). However, at large pressure changes up to several kPa, the middle ear movement clearly shows non-linear behaviour. Thus, it is possible that some small non-linear distortions are also present in the middle ear vibration at lower sound pressures. In this thesis a sensitive measurement set-up is presented to detect this weak non-linear behaviour. Essentially, this set-up consists of a loud-speaker which excites the middle ear, and the resulting vibration is measured with an heterodyne vibrometer. The use of specially designed acoustic excitation signals (odd random phase multisines) enables the separation of the linear and non-linear response. The application of this technique on the middle ear demonstrates that there are already non-linear distortions present in the vibration of the middle ear at a sound pressure of 93 dB SPL. This non-linear component also grows strongly with increasing sound pressure. Knowledge of this non-linear component can contribute to the improvement of modern hearing aids, which operate at higher sound pressures where the non-linearities could distort the signal considerably. It is also important to know the contribution of middle ear non-linearity to otoacoustic emissions. This are non-linearities caused by the active feedback amplifier in the inner ear, and can be detected in the external and middle ear. These signals are used for diagnostic purposes, and therefore it is important to have an estimate the non-linear middle ear contribution to these emissions.

Crouzon’s Syndrome with Life-Threatening Ear Bleed: Ruptured Jugular Vein Diverticulum Treated by Endovascular Embolization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mondel, Prabath Kumar, E-mail: prabathmondel@gmail.com; Anand, Sunanda, E-mail: sunandaanand@gmail.com; Limaye, Uday S., E-mail: uslkem@gmail.com

Crouzon’s syndrome is the commonest variety of syndromic craniosynostosis. Life-threatening ear bleed due to ruptured jugular venous diverticulum in Crouzon’s syndrome has not been described previously. In patients with syndromic craniosynostosis, definitive repair of jugular diverticulum by open surgery is fraught with high risk of bleeding, poor functional outcomes, and even death. A 24-year-old woman with Crouzon’s syndrome presented with conductive hearing loss and recurrent episodes of torrential bleeding from her left ear. On computed tomography, a defect in the roof of jugular fossa containing jugular venous diverticulum immediately inferior to the bony external auditory canal was seen. The clinicalmore » presentation, imaging features, and endovascular management of Crouzon’s syndrome due to a ruptured jugular venous diverticulum is described.« less

Isolating the auditory system from acoustic noise during functional magnetic resonance imaging: Examination of noise conduction through the ear canal, head, and bodya)

PubMed Central

Ravicz, Michael E.; Melcher, Jennifer R.

2007-01-01

Approaches were examined for reducing acoustic noise levels heard by subjects during functional magnetic resonance imaging (fMRI), a technique for localizing brain activation in humans. Specifically, it was examined whether a device for isolating the head and ear canal from sound (a “helmet”) could add to the isolation provided by conventional hearing protection devices (i.e., earmuffs and earplugs). Both subjective attenuation (the difference in hearing threshold with versus without isolation devices in place) and objective attenuation (difference in ear-canal sound pressure) were measured. In the frequency range of the most intense fMRI noise (1–1.4 kHz), a helmet, earmuffs, and earplugs used together attenuated perceived sound by 55–63 dB, whereas the attenuation provided by the conventional devices alone was substantially less: 30–37 dB for earmuffs, 25–28 dB for earplugs, and 39–41 dB for earmuffs and earplugs used together. The data enabled the clarification of the relative importance of ear canal, head, and body conduction routes to the cochlea under different conditions: At low frequencies (≤500 Hz), the ear canal was the dominant route of sound conduction to the cochlea for all of the device combinations considered. At higher frequencies (>500 Hz), the ear canal was the dominant route when either earmuffs or earplugs were worn. However, the dominant route of sound conduction was through the head when both earmuffs and earplugs were worn, through both ear canal and body when a helmet and earmuffs were worn, and through the body when a helmet, earmuffs, and earplugs were worn. It is estimated that a helmet, earmuffs, and earplugs together will reduce the most intense fMRI noise levels experienced by a subject to 60–65 dB SPL. Even greater reductions in noise should be achievable by isolating the body from the surrounding noise field. PMID:11206150

Handheld tympanometer measurements in conscious dogs for the evaluation of the middle ear and auditory tube.

PubMed

Strain, George M; Fernandes, Asia J

2015-06-01

Otitis externa is frequently accompanied by otitis media, yet it can be difficult to evaluate the tympanum, middle ear and auditory tube without the use of advanced radiographic imaging. The objective was to develop techniques for tympanometry testing in conscious dogs and to present normative data for clinical use of this equipment to enable assessment of the tympanum, middle ear and auditory tube. Sixteen hounds (14 female) from a school teaching colony. Dogs were gently restrained in a standing position. After cleaning of the ear canal, a tympanometer probe tip extension was placed in the vertical canal and automated testing performed using a handheld device. Both ears were tested in all dogs. Acceptable recordings were obtained from both ears of 13 dogs, from one ear in each of two dogs and from neither ear of one dog, resulting in data from 28 of 32 (88%) ears. Otoscopic examination confirmed the absence of inflammation or any other obvious explanation for the noncompliant dogs. No significant differences were seen between ears for any measure. Normative data are reported for peak compliance, peak compliance pressure, gradient and ear canal volume. Tympanograms can be recorded in conscious dogs to assist in the evaluation of the middle ear structures. © 2015 ESVD and ACVD.

Comparing otoacoustic emissions evoked by chirp transients with constant absorbed sound power and constant incident pressure magnitude

PubMed Central

Keefe, Douglas H.; Feeney, M. Patrick; Hunter, Lisa L.; Fitzpatrick, Denis F.

2017-01-01

Human ear-canal properties of transient acoustic stimuli are contrasted that utilize measured ear-canal pressures in conjunction with measured acoustic pressure reflectance and admittance. These data are referenced to the tip of a probe snugly inserted into the ear canal. Promising procedures to calibrate across frequency include stimuli with controlled levels of incident pressure magnitude, absorbed sound power, and forward pressure magnitude. An equivalent pressure at the eardrum is calculated from these measured data using a transmission-line model of ear-canal acoustics parameterized by acoustically estimated ear-canal area at the probe tip and length between the probe tip and eardrum. Chirp stimuli with constant incident pressure magnitude and constant absorbed sound power across frequency were generated to elicit transient-evoked otoacoustic emissions (TEOAEs), which were measured in normal-hearing adult ears from 0.7 to 8 kHz. TEOAE stimuli had similar peak-to-peak equivalent sound pressure levels across calibration conditions. Frequency-domain TEOAEs were compared using signal level, signal-to-noise ratio (SNR), coherence synchrony modulus (CSM), group delay, and group spread. Time-domain TEOAEs were compared using SNR, CSM, instantaneous frequency and instantaneous bandwidth. Stimuli with constant incident pressure magnitude or constant absorbed sound power across frequency produce generally similar TEOAEs up to 8 kHz. PMID:28147608

Anatomic Malformations of the Middle and Inner Ear in 22q11.2 Deletion Syndrome: Case Series and Literature Review.

PubMed

Verheij, E; Elden, L; Crowley, T B; Pameijer, F A; Zackai, E H; McDonald-McGinn, D M; Thomeer, H G X M

2018-05-01

The 22q11.2 deletion syndrome is characterized by a heterogenic phenotype, including hearing loss. The underlying cause of hearing loss, especially sensorineural hearing loss, is not yet clear. Therefore, our objective was to describe anatomic malformations in the middle and inner ear in patients with 22q11.2 deletion syndrome. A retrospective case series was conducted in 2 tertiary referral centers. All patients with 22q11.2 deletion syndrome who had undergone CT or MR imaging of the temporal bones were included. Radiologic images were evaluated on predetermined parameters, including abnormalities of the ossicular chain, cochlea, semicircular canals, and vestibule. There were 26 patients (52 ears) with a CT or MR imaging scan available. A dense stapes superstructure was found in 18 ears (36%), an incomplete partition type II was suspected in 12 cochleas (23%), the lateral semicircular canal was malformed with a small bony island in 17 ears (33%), and the lateral semicircular canal and vestibule were fused to a single cavity in 15 ears (29%). Middle and inner ear abnormalities were frequently encountered in our cohort, including malformations of the lateral semicircular canal. © 2018 by American Journal of Neuroradiology.

Planer orientation of the bilateral semicircular canals in dizzy patients.

PubMed

Aoki, Sachiko; Takei, Yasuhiko; Suzuki, Kazufumi; Masukawa, Ai; Arai, Yasuko

2012-10-01

Recent development of 3-dimensional analysis of eye movement enabled to detect the eye rotation axis, which is used to determine the responsible semicircular canal(s) in dizzy patients. Therefore, the knowledge of anatomical orientation of bilateral semicircular canals is essential, as all 6 canals influence the eye movements. Employing the new head coordinate system suitable for MR imaging, we calculated the angles of semicircular canal planes of both ears in 11 dizzy patients who had normal caloric response in both ears. The angles between adjacent canal pairs were nearly perpendicular in both ears. The angle between the posterior canal planes and head sagittal plane was 51° and significantly larger the angle between the anterior canal planes and head sagittal plane, which was 35°. The angle between the horizontal canal plane and head sagittal plane was almost orthogonal. Pairs of contralateral synergistic canal planes were not parallel, forming 10° between right and left horizontal canal planes, 17° between right anterior and left posterior canal planes and 19° between the right posterior and left anterior canal planes. Our measurement of the angles of adjacent canal pairs and the angle between each semicircular canal and head sagittal plane coincided with those of previous reports obtained from CT images and skull specimens. However, the angles between contralateral synergistic canal planes were more parallel than those of previous reports. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Continuous 24-hour measurement of middle ear pressure.

PubMed

Tideholm, B; Jönsson, S; Carlborg, B; Welinder, R; Grenner, J

1996-07-01

A new method was developed for continuous measurement of the middle ear pressure during a 24-h period. The equipment consisted of a piezo-electric pressure device and a digital memory. To allow continuous pressure recordings during normal every-day activities the equipment was made light and portable. The measurement accuracy of the equipment as well as the base-line and temperature stability were tested and found to meet to our requirements satisfactorily. In 4 volunteers with different middle ear conditions, a small perforation was made through the tympanic membrane. A rubber stopper containing a small polyethylene tube was fitted into the external ear canal. Tubal function tests were made to establish the equipment's ability to monitor fast pressure changes. The tests were well in accordance with other methods of direct pressure measurements. The equipment was carried by the volunteers for 24 h to monitor any slow or rapid dynamic pressure changes in the middle ear. Four continuous 24-h measurements are presented. The method was found to be suitable for valid measurements of dynamic pressure changes in the middle ear during normal every-day activities. It may become a useful instrument in the search for a better understanding of the development of chronic middle ear disease.

Isolated Sensorineural Hearing Loss as a Sequela after Lightning Strike

PubMed Central

Turan, Mahfuz; Kalkan, Ferhat; Bozan, Nazım; Özçalimli, İsa; Zeki Erdem, Mehmet; Yalınkılıç, Abdülaziz; Garca, Mehmet Fatih

2015-01-01

In most of the surviving patients after a lightning strike, audiovestibular abnormalities have been reported. The most frequently reported type of abnormalities is a tympanic membrane perforation with hearing loss and external ear canal burn. However a sensor neural hearing loss and mixed type hearing loss can also occur, but these occur rarely. A nineteen-year-old female patient had, after a lightning strike, serious burns on the left ear, behind the ear, and on the chest and neck. She also had in her left ear 108 dB hearing loss with irregular central perforation and in her right ear 52 dB sensorineural hearing loss. There was no hearing loss before the strike. A hearing aid was recommended for the right ear and good care and follow-up were recommended for the left ear. A lightning strike can cause serious audiological damage. Therefore, it is necessary to make a careful audiovestibular evaluation of the patients. Although there exist rarely healed cases from sensorineural hearing loss after lightning strike in literature, in our case hearing loss occurred bilaterally and then it healed unilaterally. This condition is quite rare in literature. PMID:26161278

In vivo over-expression of KGF mimic human middle ear cholesteatoma.

PubMed

Yamamoto-Fukuda, Tomomi; Akiyama, Naotaro; Shibata, Yasuaki; Takahashi, Haruo; Ikeda, Tohru; Koji, Takehiko

2015-10-01

We reported previously that keratinocyte growth factor (KGF), a mesenchymal cell-derived paracrine growth factor, plays an important role in middle ear cholesteatoma formation, which is characterized by marked proliferation of epithelial cells. Here, we investigated whether KGF, the main factor that induces cholesteatoma, overexpression in vivo results in the formation of cholesteatoma. Flag-hKGF cDNA driven by CMV14 promoter was transfected through electroporation into the external auditory canal (EAC) of rats once (short-term model) or five times on every fourth day (long-term model). Ears transfected with empty vector were used as controls. Successful transfection of plasmids into epithelial and stromal cells was confirmed by Flag immunohistochemistry. In the short-term model, the intensity of KGF protein was the strongest in hKGF transfected ear at day 4. KGF expression induced epithelial cell proliferation, reaching a peak level at day 4 and then decreased later, while in the long-term model, KGF expression in the EAC led to middle ear cholesteatoma formation. In conclusion, we described here a new experimental model of human middle ear cholesteatoma, and demonstrated that KGF and KGF receptor paracrine action play an essential role in middle ear cholesteatoma formation in an in vivo model.

Ultrasound characterization of middle ear effusion.

PubMed

Seth, Rahul; Discolo, Christopher M; Palczewska, Grazyna M; Lewandowski, Jan J; Krakovitz, Paul R

2013-01-01

To further enhance and assess the ability to characterize middle ear effusion (MEE) using non-invasive ultrasound technology. This is a prospective unblinded comparison study. Fifty-six children between the ages of 6 months and 17 years scheduled to undergo bilateral myringotomy with pressure equalization tube placement were enrolled. With the child anesthetized, the probe was placed into the external ear canal after sterile water was inserted. Ultrasound recordings of middle ear contents were analyzed by computer algorithm. Middle ear fluid was collected during myringotomy and analyzed for bacterial culture and viscosity. Ultrasound waveforms yielded a computer algorithm interpretation of middle ear contents in 66% of ears tested. When a result was obtained, the sensitivity and specificity for successfully characterizing middle ear fluid content as either void of fluid, thick fluid (mucoid), or thin fluid (serous or purulent) were at least 94%. Mucoid effusions had higher measured viscosity values (P=.002). Viscosity measures were compared to culture result, and those with low viscosity (thin consistency) had a higher likelihood of having a positive culture (P=.048). The device sensitivity and specificity for fluid detection were 94% or greater among interpretable waveforms (66% of those tested). Although this technology provides important information of the middle ear effusion presence and characteristic, further technological improvements are needed. Copyright © 2013 Elsevier Inc. All rights reserved.

Ultrasound Characterization of Middle Ear Effusion

PubMed Central

Seth, Rahul; Discolo, Christopher M; Palczewska, Grazyna M; Lewandowski, Jan J; Krakovitz, Paul R

2012-01-01

Purpose To further enhance and assess the ability to characterize middle ear effusion (MEE) using non-invasive ultrasound technology. Materials and Methods This is a prospective unblinded comparison study. Fifty-six children between the ages of 6 months and 17 years scheduled to undergo bilateral myringotomy with pressure equalization tube placement were enrolled. With the child anesthetized, the probe was placed into the external ear canal after sterile water was inserted. Ultrasound recordings of middle ear contents were analyzed by computer algorithm. Middle ear fluid was collected during myringotomy and analyzed for bacterial culture and viscosity. Results Ultrasound waveforms yielded a computer algorithm interpretation of middle ear contents in 66% of ears tested. When a result was obtained, the sensitivity and specificity for successfully characterizing middle ear fluid content as either void of fluid, thick fluid (mucoid), or thin fluid (serous or purulent) was at least 94%. Mucoid effusions had higher measured viscosity values (P=0.002). Viscosity measures were compared to culture result, and those with low viscosity (thin consistency) had a higher likelihood of having a positive culture (P=0.048). Conclusion The device sensitivity and specificity for fluid detection was 94% or greater among interpretable waveforms (66% of those tested). Although this technology provides important information of the middle ear effusion presence and characteristic, further technological improvements are needed. PMID:23084430

Swimmer's Ear (For Parents)

MedlinePlus

... scratching the ear canal, vigorous ear cleaning with cotton swabs, or putting foreign objects like bobby pins ... Also, never put objects into kids' ears, including cotton-tipped swabs. How Is Swimmer's Ear Treated? Treatment ...

[Revisional radical mastoidectomy surgeries--25 cases'experience].

PubMed

Li, L; Xie, J; Liu, Y; Gong, S S

2017-10-07

Objective: To analyze the risk factors of failure to dry ear after radical mastoidectomy and discuss key points in revisonal surgery. Methods: Clinical data of 25 patients(32 ears) with revisonal mastoidectomy were analyzed. The preoperative temporal bone CT findings, intra-operative findings, surgical procedures, postoperative operating cavities and aural abilities were recorded and analyzed. Results: All patients received preoperative temporal bone CT followed by revisonal radical mastoidectomy under microscope and general anesthesia. Among the revisonal surgeries, 19 ears(59.4%) presented cholesteatoma and 13 ears(40.6%) had no cholesteatoma. In addition, the inadequate opening for mastoid cavity and incompleted removal of the pathological tissues accounted for 90.6%(29/32), the insufficient drainage of surgical cavity for 90.6%(29/32), the lesions in tympanic ostium of eustachian tube for 31.2%(10/32), the improper operation procedures and selection of incision for 15.6%(5/32). As for the re-operation of the modified canal wall down mastoidectomy, tympanoplasty(Ⅱ) plus plastic repairing of cavity of concha were performed in 14 ears(43.8%), the modified canal wall down mastoidectomy, tympanoplasty(Ⅱ) plus reconstruction posterior bony wall of ear canal in 2 ears(6.2%); the modified canal wall down mastoidectomy, tympanoplasty(Ⅲ) plus plastic repairing of cavity of concha in 10 eras(31.3%), the modified canal wall down mastoidectomy, tympanoplasty(Ⅲ) plus reconstruction posterior boney wall of ear canal in 1 ear(3.1%); the radical mastoidectomy plus plastic repairing of cavity of concha in 5 ears(15.6%). Lodoform gauzes were packed in surgical cavity for 2 weeks and the antibiotic was used for 3 days after surgery. All patients had dressing of ears and their ears were dropped with ofloxacin regularly. The dry ear time ranged from 4 to 8 weeks, the average point was the 5th week. During a period of 6-18 months for follow-up, all patients got dried ears. The epithelialization of the operating cavity was well and the tympanic membranes were integrity. There was not pus in surgical cavities. Neither granulation tissue nor cholesteatoma was found to reoccur. Both pure tone air hearing thresholds and air-bone gap decreased in 27 ears after the revisional surgeries, with statistically significant different in comparison to those before the operation ( P <0.05). Conclusions: There are many factors leading to the failure of radical mastoidectomy, including not fully opening of the surgical cavity , incomplete removal of the lesion tissue, poor drainage of surgical cavity, the lesions in the tympanic ostium of eustachian tube, and the improper operation procedures. Treatment strategies were taken according to above factors to obtain dry ear in revisional surgeries.

Selective attention reduces physiological noise in the external ear canals of humans. I: Auditory attention

PubMed Central

Walsh, Kyle P.; Pasanen, Edward G.; McFadden, Dennis

2014-01-01

In this study, a nonlinear version of the stimulus-frequency OAE (SFOAE), called the nSFOAE, was used to measure cochlear responses from human subjects while they simultaneously performed behavioral tasks requiring, or not requiring, selective auditory attention. Appended to each stimulus presentation, and included in the calculation of each nSFOAE response, was a 30-ms silent period that was used to estimate the level of the inherent physiological noise in the ear canals of our subjects during each behavioral condition. Physiological-noise magnitudes were higher (noisier) for all subjects in the inattention task, and lower (quieter) in the selective auditory-attention tasks. These noise measures initially were made at the frequency of our nSFOAE probe tone (4.0 kHz), but the same attention effects also were observed across a wide range of frequencies. We attribute the observed differences in physiological-noise magnitudes between the inattention and attention conditions to different levels of efferent activation associated with the differing attentional demands of the behavioral tasks. One hypothesis is that when the attentional demand is relatively great, efferent activation is relatively high, and a decrease in the gain of the cochlear amplifier leads to lower-amplitude cochlear activity, and thus a smaller measure of noise from the ear. PMID:24732069

Anatomy, Physiology and Function of the Auditory System

NASA Astrophysics Data System (ADS)

Kollmeier, Birger

The human ear consists of the outer ear (pinna or concha, outer ear canal, tympanic membrane), the middle ear (middle ear cavity with the three ossicles malleus, incus and stapes) and the inner ear (cochlea which is connected to the three semicircular canals by the vestibule, which provides the sense of balance). The cochlea is connected to the brain stem via the eighth brain nerve, i.e. the vestibular cochlear nerve or nervus statoacusticus. Subsequently, the acoustical information is processed by the brain at various levels of the auditory system. An overview about the anatomy of the auditory system is provided by Figure 1.

Comparison of Ear-Canal Reflectance and Umbo Velocity in Patients with Conductive Hearing Loss

NASA Astrophysics Data System (ADS)

Merchant, Gabrielle R.; Nakajima, Hideko H.; Pisano, Dominic V.; Röösli, Christof; Hamade, Mohamad A.; Mafoud, Lorice; Halpin, Christopher F.; Merchant, Saumil N.; Rosowski, John J.

2011-11-01

Patients who present at hearing clinics with a conductive hearing loss (CHL) in the presence of an intact, healthy tympanic membrane create a unique challenge for otologists. While patient counseling, treatment options, and outcome vary with differing middle-ear pathologies, a non-invasive diagnostic that can differentiate between these pathologies does not currently exist. We evaluated the clinical utility and diagnostic accuracy of two non-invasive measures of middle-ear mechanics: ear-canal reflectance (ECR) and umbo velocity (VU).

To analyze the impact of intracavitary brachytherapy as boost radiation after external beam radiotherapy in carcinoma of the external auditory canal and middle ear: a retrospective analysis.

PubMed

Badakh, Dinesh K; Grover, Amit H

2014-01-01

The purpose of this study was to analyze the impact of intra-cavitary brachytherapy (ICBT) as boost radiation after external beam radiotherapy (EBRT) in carcinoma of the external auditory canal and middle ear (EACMA): A retrospective analysis. A retrospective study of 18 patients with carcinoma of the EACMA who were treated with a curative intent from the year 1998 to 2010 was carried out. The age of the patients ranged from 25 years to 67 years. There were 11 male patients (61.1%) and 7 female patients (38.9%). A total of 15 (88.2%) patients were treated with curative radiation alone after a biopsy and two patients received post-operative radiation therapy. The patients were initially treated with EBRT with cobalt 60 machine up to 60-64 Gy. In our department, all the patients who were technically suitable for ICBT received an ICBT boost. The overall survival (OS) in these patients ranged from 7 months to 151 months (9 out of 17 patients, no evidence of disease 53%). The OS in patients treated with a combination of EBRT with ICBT was (8 out of 11) 72.7%, P value statistically significant (P value: 0.0024). The multivariate analysis shows statistically significant difference only for patients who got an ICBT boost (P Value: 0.020). ICBT as a boost after EBRT has got a positive impact on the OS. In conclusion, our results demonstrate that radical radiation therapy (EBRT and ICBT) is the treatment of choice for stage T2, carcinoma of EACMA.

Comparison of Boric Acid and Combination Drug of Polymyxin, Neomycin and Hydrocortisone (polymyxin NH) in the Treatment of Acute Otitis Externa.

PubMed

Amani, Soroush; Moeini, Mohammad

2016-07-01

Acute otitis externa is an inflammation of the external auditory canal known as "swimmer's ear". Direct costs including medical treatment, painkillers, antibiotics, steroids or both and indirect costs are also remarkable. The aim of this study was to compare the effect of boric acid and polymyxin, neomycin and hydrocortisone composition in the treatment of acute otitis externa. This randomized clinical trial was carried out on 80 patients aged more than 17-year-old who were referred to Kashani hospital clinic with a diagnosis of acute otitis externa by otolaryngologist. The patients were randomly allocated to two groups (A: Boric acid and B: polymyxin NH ear drops) and Painkiller was prescribed and administered orally for all patients and in the presence of fever, cellulitis around the ears and neck adenopathy, broad-spectrum systemic antibiotics were used besides topical treatment. Symptoms of patients who were evaluated by a physician includes pain, discharge from the ear, swelling of the ear canal, auricle swelling, tenderness, and ear itching. In addition, pain was evaluated in patients and was recorded by Macgill Pain Questionnaire, in the first, third, seventh and tenth days. Results showed that itching on third day (p=0.007) and swelling of the ear canal in the examination of the third day (p=0.006) and the seventh day (p=0.001) in the polymyxin NH group was more than those of boric acid group. Overall mean pain based on McGill questionnaire was 11.10±1.49 in boric acid group in the examination on the first day and was 4.05±0.22 in the examination on the tenth day and in the polymyxin NH group, it was 10.9±0.99 on the first day and 4.20±0.40 on the tenth day. In both groups, pain relief was the same and there was no significant difference between two groups (p=0.075). The findings of this study showed slight differences in the effectiveness of the boric acid drug and combination of polymyxin, neomycin and hydrocortisone in the treatment of patients with acute otitis externa that is of clinical significance.

Comparison of Boric Acid and Combination Drug of Polymyxin, Neomycin and Hydrocortisone (polymyxin NH) in the Treatment of Acute Otitis Externa

PubMed Central

Moeini, Mohammad

2016-01-01

Introduction Acute otitis externa is an inflammation of the external auditory canal known as "swimmer’s ear". Direct costs including medical treatment, painkillers, antibiotics, steroids or both and indirect costs are also remarkable. Aim The aim of this study was to compare the effect of boric acid and polymyxin, neomycin and hydrocortisone composition in the treatment of acute otitis externa. Materials and Methods This randomized clinical trial was carried out on 80 patients aged more than 17-year-old who were referred to Kashani hospital clinic with a diagnosis of acute otitis externa by otolaryngologist. The patients were randomly allocated to two groups (A: Boric acid and B: polymyxin NH ear drops) and Painkiller was prescribed and administered orally for all patients and in the presence of fever, cellulitis around the ears and neck adenopathy, broad-spectrum systemic antibiotics were used besides topical treatment. Symptoms of patients who were evaluated by a physician includes pain, discharge from the ear, swelling of the ear canal, auricle swelling, tenderness, and ear itching. In addition, pain was evaluated in patients and was recorded by Macgill Pain Questionnaire, in the first, third, seventh and tenth days. Results Results showed that itching on third day (p=0.007) and swelling of the ear canal in the examination of the third day (p=0.006) and the seventh day (p=0.001) in the polymyxin NH group was more than those of boric acid group. Overall mean pain based on McGill questionnaire was 11.10±1.49 in boric acid group in the examination on the first day and was 4.05±0.22 in the examination on the tenth day and in the polymyxin NH group, it was 10.9±0.99 on the first day and 4.20±0.40 on the tenth day. In both groups, pain relief was the same and there was no significant difference between two groups (p=0.075). Conclusion The findings of this study showed slight differences in the effectiveness of the boric acid drug and combination of polymyxin, neomycin and hydrocortisone in the treatment of patients with acute otitis externa that is of clinical significance. PMID:27630871

The RetroX auditory implant for high-frequency hearing loss.

PubMed

Garin, P; Genard, F; Galle, C; Jamart, J

2004-07-01

The objective of this study was to analyze the subjective satisfaction and measure the hearing gain provided by the RetroX (Auric GmbH, Rheine, Germany), an auditory implant of the external ear. We conducted a retrospective case review. We conducted this study at a tertiary referral center at a university hospital. We studied 10 adults with high-frequency sensori-neural hearing loss (ski-slope audiogram). The RetroX consists of an electronic unit sited in the postaural sulcus connected to a titanium tube implanted under the auricle between the sulcus and the entrance of the external auditory canal. Implanting requires only minor surgery under local anesthesia. Main outcome measures were a satisfaction questionnaire, pure-tone audiometry in quiet, speech audiometry in quiet, speech audiometry in noise, and azimuth audiometry (hearing threshold in function of sound source location within the horizontal plane at ear level). : Subjectively, all 10 patients are satisfied or even extremely satisfied with the hearing improvement provided by the RetroX. They wear the implant daily, from morning to evening. We observe a statistically significant improvement of pure-tone thresholds at 1, 2, and 4 kHz. In quiet, the speech reception threshold improves by 9 dB. Speech audiometry in noise shows that intelligibility improves by 26% for a signal-to-noise ratio of -5 dB, by 18% for a signal-to-noise ratio of 0 dB, and by 13% for a signal-to-noise ratio of +5 dB. Localization audiometry indicates that the skull masks sound contralateral to the implanted ear. Of the 10 patients, one had acoustic feedback and one presented with a granulomatous reaction to the foreign body that necessitated removing the implant. The RetroX auditory implant is a semi-implantable hearing aid without occlusion of the external auditory canal. It provides a new therapeutic alternative for managing high-frequency hearing loss.

Ear malformations, hearing loss and hearing rehabilitation in children with Treacher Collins syndrome.

PubMed

Rosa, Francisco; Coutinho, Miguel Bebiano; Ferreira, João Pinto; Sousa, Cecilia Almeida

2016-01-01

The aim of this study was to assess the main ear malformations, hearing loss and auditory rehabilitation in children with Treacher Collins syndrome. We performed a retrospective study of 9 children with Treacher Collins syndrome treated in a central hospital between January 2003 and January 2013. This study showed a high incidence of malformations of the outer and middle ear, such as microtia, atresia or stenosis of the external auditory canal, hypoplastic middle ear cavity, dysmorphic or missing ossicular chain. Most patients had bilateral hearing loss of moderate or high degree. In the individuals studied, there was functional improvement in patients with bone-anchored hearing aids in relation to conventional hearing aids by bone conduction. Treacher Collins syndrome is characterized by bilateral malformations of the outer and middle ear. Hearing rehabilitation in these children is of utmost importance, and bone-anchored hearing aids is the method of choice. Copyright © 2014 Elsevier España, S.L.U. y Sociedad Española de Otorrinolaringología y Cirugía de Cabeza y Cuello. All rights reserved.

Different clinical presentation and management of temporal bone fibrous dysplasia in children.

PubMed

Mierzwiński, Józef; Kosowska, Justyna; Tyra, Justyna; Haber, Karolina; Drela, Maria; Paczkowski, Dariusz; Burduk, Paweł

2018-01-15

Fibrous dysplasia is a slowly progressive benign fibro-osseous disorder that involves one or multiple bones with a unilateral distribution in most cases. It is a lesion of unknown etiology, uncertain pathogenesis, and diverse histopathology. Temporal bone involvement is the least frequently reported type, especially in children. We reviewed available articles regarding fibrous dysplasia with temporal bone involvement in children and added four patients aged 7 to 17 years who were diagnosed and treated in our institution from 2006 to 2017. The patients' clinical picture comprised head deformity, external canal stenosis, headache, progressive conductive and/or sensorineural hearing loss, tinnitus, and sudden deafness. Two patients had experienced severe episodic vertigo with nausea and vomiting. Two were referred to us with external canal obstruction and secondary cholesteatoma formation with broad middle ear destruction. One was diagnosed with acute mastoiditis and intracranial complications. Optimal management of fibrous dysplasia is unclear and can be challenging, especially in children. In our two patients with disease expansion and involvement of important structures, surgical treatment was abandoned and a "wait-and-scan" policy was applied. The other two were qualified for surgical treatment. One patient underwent two surgeries: modified lateral petrosectomy (canal left open) with pathological tissue removal, cavity obliteration, and subsequent tympanoplasty. Another patient with extensive destruction of the left temporal bone underwent canal wall down mastoidectomy with perisinus abscess drainage and revision 12 months later. Tympanoplasty was unsatisfactory in both patients because of slow progression of the middle ear pathology. None of our patients underwent pharmacological treatment. In younger patients, observation and a "wait-and-scan" protocol is relevant until significant function, or cosmetic deficits are obvious. Surgery is not preferred and should be delayed until puberty because fibrous dysplasia has a tendency to stabilize after adolescence. In patients with severe symptoms medical treatment can be implemented, but safety of this treatment in children remain controversial.

Do high sound pressure levels of crowing in roosters necessitate passive mechanisms for protection against self-vocalization?

PubMed

Claes, Raf; Muyshondt, Pieter G G; Dirckx, Joris J J; Aerts, Peter

2018-02-01

High sound pressure levels (>120dB) cause damage or death of the hair cells of the inner ear, hence causing hearing loss. Vocalization differences are present between hens and roosters. Crowing in roosters is reported to produce sound pressure levels of 100dB measured at a distance of 1m. In this study we measured the sound pressure levels that exist at the entrance of the outer ear canal. We hypothesize that roosters may benefit from a passive protective mechanism while hens do not require such a mechanism. Audio recordings at the level of the entrance of the outer ear canal of crowing roosters, made in this study, indeed show that a protective mechanism is needed as sound pressure levels can reach amplitudes of 142.3dB. Audio recordings made at varying distances from the crowing rooster show that at a distance of 0.5m sound pressure levels already drop to 102dB. Micro-CT scans of a rooster and chicken head show that in roosters the auditory canal closes when the beak is opened. In hens the diameter of the auditory canal only narrows but does not close completely. A morphological difference between the sexes in shape of a bursa-like slit which occurs in the outer ear canal causes the outer ear canal to close in roosters but not in hens. Copyright © 2017 Elsevier GmbH. All rights reserved.

Biomedical Simulation Models of Human Auditory Processes

NASA Technical Reports Server (NTRS)

Bicak, Mehmet M. A.

2012-01-01

Detailed acoustic engineering models that explore noise propagation mechanisms associated with noise attenuation and transmission paths created when using hearing protectors such as earplugs and headsets in high noise environments. Biomedical finite element (FE) models are developed based on volume Computed Tomography scan data which provides explicit external ear, ear canal, middle ear ossicular bones and cochlea geometry. Results from these studies have enabled a greater understanding of hearing protector to flesh dynamics as well as prioritizing noise propagation mechanisms. Prioritization of noise mechanisms can form an essential framework for exploration of new design principles and methods in both earplug and earcup applications. These models are currently being used in development of a novel hearing protection evaluation system that can provide experimentally correlated psychoacoustic noise attenuation. Moreover, these FE models can be used to simulate the effects of blast related impulse noise on human auditory mechanisms and brain tissue.

Congenital cholesteatoma of the infratemporal fossa with congenital aural atresia and mastoiditis: a case report.

PubMed

Abdel-Aziz, Mosaad

2012-06-25

Congenital cholesteatoma may be expected in abnormally developed ear, it may cause bony erosion of the middle ear cleft and extend to the infratemporal fossa. We present the first case of congenital cholesteatoma of the infratemporal fossa in a patient with congenital aural atresia that has been complicated with acute mastoiditis. A sixteen year old Egyptian male patient presented with congenital cholesteatoma of the infratemporal fossa with congenital aural atresia complicated with acute mastoiditis. Two weeks earlier, the patient suffered pain necessitating hospital admission, magnetic resonance imaging revealed a soft tissue mass in the right infratemporal fossa. On presentation to our institute, Computerized tomography was done as a routine, it proved the diagnosis of mastoiditis, pure tone audiometry showed an air-bone gap of 60 dB. Cortical mastoidectomy was done for treatment of mastoiditis, removal of congenital cholesteatoma was carried out with reconstruction of external auditory canal. Follow-up of the patient for 2 years and 3 months showed a patent, infection free external auditory canal with an air-bone gap has been reduced to 35db. One year after the operation; MRI was done and it showed no residual or recurrent cholesteatoma. Congenital cholesteatoma of the infratemporal fossa in cases of congenital aural atresia can be managed safely even if it was associated with mastoiditis. It is an original case report of interest to the speciality of otolaryngology.

Finite-Element Modelling of the Acoustic Input Admittance of the Newborn Ear Canal and Middle Ear.

PubMed

Motallebzadeh, Hamid; Maftoon, Nima; Pitaro, Jacob; Funnell, W Robert J; Daniel, Sam J

2017-02-01

Admittance measurement is a promising tool for evaluating the status of the middle ear in newborns. However, the newborn ear is anatomically very different from the adult one, and the acoustic input admittance is different than in adults. To aid in understanding the differences, a finite-element model of the newborn ear canal and middle ear was developed and its behaviour was studied for frequencies up to 2000 Hz. Material properties were taken from previous measurements and estimates. The simulation results were within the range of clinical admittance measurements made in newborns. Sensitivity analyses of the material properties show that in the canal model, the maximum admittance and the frequency at which that maximum admittance occurs are affected mainly by the stiffness parameter; in the middle-ear model, the damping is as important as the stiffness in influencing the maximum admittance magnitude but its effect on the corresponding frequency is negligible. Scaling up the geometries increases the admittance magnitude and shifts the resonances to lower frequencies. The results suggest that admittance measurements can provide more information about the condition of the middle ear when made at multiple frequencies around its resonance.

Tumor Stage-Related Role of Radiotherapy in Patients with an External Auditory Canal and Middle Ear Carcinoma.

PubMed

Choi, Jinhyun; Kim, Se-Heon; Koh, Yoon Woo; Choi, Eun Chang; Lee, Chang Geol; Keum, Ki Chang

2017-01-01

The purpose of this study was to evaluate the clinical outcomes of patients treated with radiotherapy (RT) for a carcinoma of the external auditory canal (EAC) and middle ear. The records of 32 patients who received RT from 1990 to 2013 were reviewed retrospectively. The Pittsburgh classification was used to stage all the cancers (early stage, T1/T2 [n=12]; advanced stage, T3/T4 or N positive [n=20]). Twenty-one patients (65.6%) were treated with postoperative RT and 11 patients (34.4%) were treated with definitive RT. The median radiation doses for postoperative and definitive RT were 60 Gy and 64.8 Gy, respectively. Chemotherapy was administered to seven patients (21.9%). The 5-year overall survival and disease-free survival rates for all patients were 57% and 52%, respectively. The disease control rates for the patients with early stage versus advanced stage carcinomawere 55.6% (5/9) and 50% (6/12) in the postoperative RT group and 66.7% (2/3) and 37.5% (3/8) in the definitive RT group, respectively. Overall, 15 cases (14 patients, 46.7%) experienced treatment failure; these failures were classified as local in four cases, regional in one case, and distant in 10 cases. The median follow-up period after RT was 51 months (range, 7 to 286 months). Patients with early stage carcinoma achieved better outcomes when definitive RT was used. Advanced stage carcinoma patients experienced better outcomes with postoperative RT. The high rate of distant failure after RT, with or without surgery, reflected the lack of a consensus regarding the best therapeutic approach for treating carcinoma of the EAC and middle ear.

Congenital aural atresia.

PubMed

Abdel-Aziz, Mosaad

2013-07-01

Congenital aural atresia is a spectrum of ear deformities present at birth that involves some degree of failure of the development of the external auditory canal. This malformation may be associated with other congenital anomalies; it occurs as a result of abnormal development of the first and second branchial arches and the first branchial cleft and most often occurs sporadically, although the disease may be manifested in different syndromes. Congenital aural atresia is considered one of the most difficult and challenging surgeries for the otologic surgeon. The goals of atresia surgery are to restore functional hearing, preferably without the requirement of a hearing aid, and to reconstruct a patent, infection-free external auditory canal. The repair is usually done at the age of 6 years, so children with bilateral atresia may need hearing amplification in the first few weeks of life until the age at surgery. To optimize the surgical outcome, careful audiological and radiological evaluation of the patient should be performed preoperatively. Also, postoperative frequent packing and regular follow-up are mandatory to avoid restenosis and infection of the newly created canal. With careful intraoperative dissection and regular follow-up, complications of surgery can be avoided.

Histological study of the external, middle and inner ear of horses.

PubMed

Blanke, A; Aupperle, H; Seeger, J; Kubick, C; Schusser, G F

2015-12-01

Clinical, anatomical and histological aspects of the equine acoustic organ have been poorly investigated and illustrated in literature so far. It is understood that an intact acoustic organ and hearing function are of vital importance for the well-being of flight animals like horses. The knowledge of the acoustic organ is usually transferred analogously from other mammals to horses. The purpose of this study was to provide a detailed and complete histological description of the healthy equine auditory organ, and to determine its congruity to other mammalians. Anatomical dissections and histological preparations were carried out on ten cadaver heads. Specimens of various parts of the equine acoustic organ were taken and evaluated histologically. The histological composition of external, middle and inner ear structures are predominantly congruent to those of other mammals, especially to human beings. Unique inwardly directed rete pegs within the osseous ear canal and the prominent tensor tympani muscle are described for the first time. Results obtained in this study can be employed as references for further research on the equine acoustic organ and improve the understanding of the clinical development of hearing loss, otitis externa/media/interna or tympanosclerosis. © 2014 Blackwell Verlag GmbH.

Anatomy of the lamprey ear: morphological evidence for occurrence of horizontal semicircular ducts in the labyrinth of Petromyzon marinus

USGS Publications Warehouse

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.

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

PubMed

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. © 2016 Wiley Periodicals, Inc.

First branchial cleft anomaly.

PubMed Central

Al-Fallouji, M. A.; Butler, M. F.

1983-01-01

A 15-year-old girl presented with a cystic swelling since birth behind the ramus of the right mandible and diagnosed clinically as a dermoid cyst. Surgical exploration, however, showed that it was closely related to the external auditory canal, with an extension running medially behind the parotid gland and ending in the bony middle ear. The facial nerve was closely related to the deep part of the cyst. Such an anatomical position indicates that this was a first branchial cleft anomaly. Surgical excision of the cyst was performed. PMID:6622327

Influence of different boundary conditions at the tympanic annulus on finite element models of the human middle ear

NASA Astrophysics Data System (ADS)

Lobato, Lucas; Paul, Stephan; Cordioli, Júlio

2018-05-01

The tympanic annulus is a fibrocartilage ligament that supports the tympanic membrane in a sulcus at the end of the outer ear canal. Among many FE models of the middle ear found in literature, the effect of different boundary conditions at tympanic annulus on middle ear mechanics was not found. In order to investigate the influence of different representations of this detail in FE models, three different ways to connect the tympanic annulus to the outer ear canal were modelled in a reduced middle ear system. This reduced system includes tympanic membrane, tympanic annulus, manubrium, malleus and anterior ligament of malleus. The numerical frequency response function Humbo (umbo velocity vs sound pressure at tympanic membrane) was analyzed through the different boundary conditions and compared to numerical and experimental data from the literature. Also a numerical modal analysis was performed to improve the analysis. It was found that the boundary conditions used to represent the connection between Tympanic Annulus and Outer Ear Canal can change the global stiffness of the system and its natural frequencies as well as change the modal shape of high order modes.

A mechano-acoustic model of the effect of superior canal dehiscence on hearing in chinchilla

PubMed Central

Songer, Jocelyn E.; Rosowski, John J.

2008-01-01

Superior canal dehiscence (SCD) is a pathological condition of the ear that can cause a conductive hearing loss. The effect of SCD (a hole in the bony wall of the superior semicircular canal) on chinchilla middle- and inner-ear mechanics is analyzed with a circuit model of the dehiscence. The model is used to predict the effect of dehiscence on auditory sensitivity and mechanics. These predictions are compared to previously published measurements of dehiscence related changes in chinchilla cochlear potential, middle-ear input admittance and stapes velocity. The comparisons show that the model predictions are both qualitatively and quantitatively similar to the physiological results for frequencies where physiologic data are available. The similarity supports the third-window hypothesis of the effect of superior canal dehiscence on auditory sensitivity and mechanics and provides the groundwork for the development of a model that predicts the effect of superior canal dehiscence syndrome on auditory sensitivity and mechanics in humans. PMID:17672643

Expression and function of FGF10 in mammalian inner ear development

NASA Technical Reports Server (NTRS)

Pauley, Sarah; Wright, Tracy J.; Pirvola, Ulla; Ornitz, David; Beisel, Kirk; Fritzsch, Bernd

2003-01-01

We have investigated the expression of FGF10 during ear development and the effect of an FGF10 null mutation on ear development. Our in situ hybridization data reveal expression of FGF10 in all three canal crista sensory epithelia and the cochlea anlage as well as all sensory neurons at embryonic day 11.5 (E11.5). Older embryos (E18.5) displayed strong graded expression in all sensory epithelia. FGF10 null mutants show complete agenesis of the posterior canal crista and the posterior canal. The posterior canal sensory neurons form initially and project rather normally by E11.5, but they disappear within 2 days. FGF10 null mutants have no posterior canal system at E18.5. In addition, these mutants have deformations of the anterior and horizontal cristae, reduced formation of the anterior and horizontal canals, as well as altered position of the remaining sensory epithelia with respect to the utricle. Hair cells form but some have defects in their cilia formation. No defects were detected in the organ of Corti at the cellular level. Together these data suggest that FGF10 plays a major role in ear morphogenesis. Most of these data are consistent with earlier findings on a null mutation in FGFR2b, one of FGF10's main receptors. Copyright 2003 Wiley-Liss, Inc.

Specification of absorbed-sound power in the ear canal: Application to suppression of stimulus frequency otoacoustic emissions

PubMed Central

Keefe, Douglas H.; Schairer, Kim S.

2011-01-01

An insert ear-canal probe including sound source and microphone can deliver a calibrated sound power level to the ear. The aural power absorbed is proportional to the product of mean-squared forward pressure, ear-canal area, and absorbance, in which the sound field is represented using forward (reverse) waves traveling toward (away from) the eardrum. Forward pressure is composed of incident pressure and its multiple internal reflections between eardrum and probe. Based on a database of measurements in normal-hearing adults from 0.22 to 8 kHz, the transfer-function level of forward relative to incident pressure is boosted below 0.7 kHz and within 4 dB above. The level of forward relative to total pressure is maximal close to 4 kHz with wide variability across ears. A spectrally flat incident-pressure level across frequency produces a nearly flat absorbed power level, in contrast to 19 dB changes in pressure level. Calibrating an ear-canal sound source based on absorbed power may be useful in audiological and research applications. Specifying the tip-to-tail level difference of the suppression tuning curve of stimulus frequency otoacoustic emissions in terms of absorbed power reveals increased cochlear gain at 8 kHz relative to the level difference measured using total pressure. PMID:21361437

Chinchilla middle ear transmission matrix model and middle-ear flexibilitya)

PubMed Central

Ravicz, Michael E.; Rosowski, John J.

2017-01-01

The function of the middle ear (ME) in transforming ME acoustic inputs and outputs (sound pressures and volume velocities) can be described with an acoustic two-port transmission matrix. This description is independent of the load on the ME (cochlea or ear canal) and holds in either direction: forward (from ear canal to cochlea) or reverse (from cochlea to ear canal). A transmission matrix describing ME function in chinchilla, an animal commonly used in auditory research, is presented, computed from measurements of forward ME function: input admittance YTM, ME pressure gain GMEP, ME velocity transfer function HV, and cochlear input admittance YC, in the same set of ears [Ravicz and Rosowski (2012b). J. Acoust. Soc. Am. 132, 2437–2454; (2013a). J. Acoust. Soc. Am. 133, 2208–2223; (2013b). J. Acoust. Soc. Am. 134, 2852–2865]. Unlike previous estimates, these computations require no assumptions about the state of the inner ear, effectiveness of ME manipulations, or measurements of sound transmission in the reverse direction. These element values are generally consistent with physical constraints and the anatomical ME “transformer ratio.” Differences from a previous estimate in chinchilla [Songer and Rosowski (2007). J. Acoust. Soc. Am. 122, 932–942] may be due to a difference in ME flexibility between the two subject groups. PMID:28599566

Chinchilla middle ear transmission matrix model and middle-ear flexibility.

PubMed

Ravicz, Michael E; Rosowski, John J

2017-05-01

The function of the middle ear (ME) in transforming ME acoustic inputs and outputs (sound pressures and volume velocities) can be described with an acoustic two-port transmission matrix. This description is independent of the load on the ME (cochlea or ear canal) and holds in either direction: forward (from ear canal to cochlea) or reverse (from cochlea to ear canal). A transmission matrix describing ME function in chinchilla, an animal commonly used in auditory research, is presented, computed from measurements of forward ME function: input admittance Y TM , ME pressure gain G MEP , ME velocity transfer function H V , and cochlear input admittance Y C , in the same set of ears [Ravicz and Rosowski (2012b). J. Acoust. Soc. Am. 132, 2437-2454; (2013a). J. Acoust. Soc. Am. 133, 2208-2223; (2013b). J. Acoust. Soc. Am. 134, 2852-2865]. Unlike previous estimates, these computations require no assumptions about the state of the inner ear, effectiveness of ME manipulations, or measurements of sound transmission in the reverse direction. These element values are generally consistent with physical constraints and the anatomical ME "transformer ratio." Differences from a previous estimate in chinchilla [Songer and Rosowski (2007). J. Acoust. Soc. Am. 122, 932-942] may be due to a difference in ME flexibility between the two subject groups.

Testing a Method for Quantifying the Output of Implantable Middle Ear Hearing Devices

PubMed Central

Rosowski, J.J.; Chien, W.; Ravicz, M.E.; Merchant, S.N.

2008-01-01

This report describes tests of a standard practice for quantifying the performance of implantable middle ear hearing devices (also known as implantable hearing aids). The standard and these tests were initiated by the Food and Drug Administration of the United States Government. The tests involved measurements on two hearing devices, one commercially available and the other home built, that were implanted into ears removed from human cadavers. The tests were conducted to investigate the utility of the practice and its outcome measures: the equivalent ear canal sound pressure transfer function that relates electrically driven middle ear velocities to the equivalent sound pressure needed to produce those velocities, and the maximum effective ear canal sound pressure. The practice calls for measurements in cadaveric ears in order to account for the varied anatomy and function of different human middle ears. PMID:17406105

A randomised controlled trial of active chronic otitis media comparing courses of eardrops versus one-off topical treatments suitable for primary, secondary and tertiary healthcare settings.

PubMed

Loock, J W

2012-08-01

Primary: to compare one-off administration of boric acid powder with courses of 1% acetic acid and ciprofloxacin eardrops in treating active chronic otitis media. Secondary: to evaluate the effectiveness of Quadriderm® cream in resistant active chronic otitis media; and to document side effects of these treatments, especially hearing loss. Randomised controlled trial. Outpatient department of a tertiary ENT unit. Hundred and fifty-nine patients over 6 years old with active chronic mucosal (without cholesteatoma) otitis media randomised to receive one of the three primary agents. All techniques employed were suitable for primary healthcare givers as well as specialists. After confirming eligibility, patients were randomly allocated to treatment. All ears underwent toilet with irrigation using clean water, a syringe and ambient light, with or without dry mopping, until the perforation was visible. The randomised solution was flushed through the middle ear and eustachian tube using a 'tragal pump' technique: saline was used as the solution for flushing in the boric acid powder arm. Patients allocated topical ear medication were given a bottle of eardrops to administer (six drops twice daily, 'pumped in') until finished. Those allocated boric acid powder had the external ear canals filled as a one-off treatment. Patients were followed up monthly thereafter. Primary: Dry (inactive) middle ears as assessed by the doctor. Secondary: Patient assessment of success; microbiologic culture and sensitivity; audiologic changes because of treatment; complications of treatment; costs of therapies. Ciprofloxacin eardrops and boric acid powder were statistically superior to 1% acetic acid eardrops in rendering active chronic otitis media inactive (73% dry ears for ciprofloxacin; 67% for boric acid powder; and 24% for acetic acid). There was no difference between the success rates of ciprofloxacin eardrops and boric acid powder. Quadriderm cream was effective in 85% of patients failing first-line therapy. No agent caused significant complications and specifically no hearing loss. This study showed a single application of boric acid powder following external auditory canal irrigation until the perforation was visible to be as effective as the current best practice of topical quinolone eardrops in active chronic otitis media. Boric acid powder is inexpensive and does not require patient compliance. Boric acid powder is a viable, less costly alternative to topical antibiotic/steroid ear drops in the developing world for active chronic otitis media. Acetic acid eardrops 1% are ineffective. Quadriderm cream, given as a one-off therapy, also appears to be effective. © 2012 Blackwell Publishing Ltd.

Equivalent Ear Canal Volumes in Children Pre- and Post-Tympanostomy Tube Insertion.

ERIC Educational Resources Information Center

Shanks, Janet E.; And Others

1992-01-01

Evaluation of preoperative and postoperative equivalent ear canal volume measures on 334 children (ages 6 weeks to 6.7 years) with chronic otitis media with effusion found that the determination could be made very accurately for children 4 years and older. Criterion values for tympanic membrane perforation and preoperative and postoperative…

Communication routes between intracranial spaces and inner ear: function, pathophysiologic importance and relations with inner ear diseases.

PubMed

Ciuman, Raphael R

2009-01-01

There exist 3 communication routes between the intracranial space and the inner ear, the vestibular aqueduct, the cochlear aqueduct, and the internal auditory canal. They possess a key role in inner ear pressure regulation and fluid homeostasis and are related to inner ear diseases. Relevant literature was reviewed, and the current knowledge of the anatomy, physiologic importance, and relations to inner ear diseases were described. Pathologic communication routes such as semicircular canal dehiscence syndrome were highlighted as well. Abnormalities in all 3 communication routes may predispose or be the cause of distinct inner ear pathologic condition and involved in other cochlear and vestibular syndromes, in which their role is not completely clear. The increasing knowledge of the underlying mechanisms encourages promising approaches for possible intervention in the future.

Popularity and Harms of Aural Foreign Bodies: A Descriptive Study of Patients in Baqiyatallah University Hospital, Tehran, Iran.

PubMed

Taheri, Abolfazl; Mehmandari, Sina Navaei; Shahidi, Mojtaba; Mehdizadeh, Hamidreza; Mirlohi, Seyyed Mohammad Javad; Aref, Nasrin Mohammadi; Avanaki, Mahsa Alborzi; Khosravi, Mohammad Hossein

2017-12-01

To evaluate the prevalence of external ear complications among Iranian aural foreign body users attending to otolaryngology clinic of our hospital. In this cross-sectional study patients attending to Otolaryngology clinics of Baqiyatallah hospital were enrolled regardless of their age, gender and reason of attending. Patients between 15 and 60 years of age were included in the present study. Those with positive history of chronic ear diseases, ear surgery, congenital ear disorders, trauma to ear or head and neck region or shock wave trauma were excluded from the study. Demographic information as well as data on chief complaint, educational level, frequency and type of used foreign body and findings of physical examination and Otoscopy by a single otolaryngologist were recorded in a predesigned checklist. Eventually 362 patients (232 male and 130 female) with a mean age of 40.32 ± 16.90 years underwent analysis. Of all patients 244 (67.2%) were using a kind of aural foreign body frequently and Cotton bud was the most popular (63.5%) used foreign body among patients. Drying ear canal was the most common (54.9%) reason of using AFBs among study individuals followed by itching (29.5%) and pyorrhea (11.06%). Also 11 (4.5%) patients were using AFBs as a habit with no specific reason. Itching was the most prevalent symptom reported by both aural foreign body users (78%) and non-users (45.5%); however it was significantly higher among AFB users (p = 0.026). Also hearing loss was significantly more reported by AFB users (p = 0.033). A majority of patients had normal physical examination in both AFB users and non-users group. Inflammation of ear canal was significantly more detected in AFB users (p = 0.004). In addition, rate of right ear wax impaction was higher among AFB users (p = 0.016). In conclusion we realized that 67.2% of patients attending to Otolaryngology clinic of our hospital were using a kind of aural foreign bodies and itching was the most common chief complaint of these patients.

External and middle ear sound pressure distribution and acoustic coupling to the tympanic membrane

PubMed Central

Bergevin, Christopher; Olson, Elizabeth S.

2014-01-01

Sound energy is conveyed to the inner ear by the diaphanous, cone-shaped tympanic membrane (TM). The TM moves in a complex manner and transmits sound signals to the inner ear with high fidelity, pressure gain, and a short delay. Miniaturized sensors allowing high spatial resolution in small spaces and sensitivity to high frequencies were used to explore how pressure drives the TM. Salient findings are: (1) A substantial pressure drop exists across the TM, and varies in frequency from ∼10 to 30 dB. It thus appears reasonable to approximate the drive to the TM as being defined solely by the pressure in the ear canal (EC) close to the TM. (2) Within the middle ear cavity (MEC), spatial variations in sound pressure could vary by more than 20 dB, and the MEC pressure at certain locations/frequencies was as large as in the EC. (3) Spatial variations in pressure along the TM surface on the EC-side were typically less than 5 dB up to 50 kHz. Larger surface variations were observed on the MEC-side. PMID:24606269

Non-invasive estimation of middle-ear input impedance and efficiency.

PubMed

Lewis, James D; Neely, Stephen T

2015-08-01

A method to transform the impedance measured in the ear canal, ZEC, to the plane of the eardrum, ZED, is described. The portion of the canal between the probe and eardrum was modeled as a concatenated series of conical segments, allowing for spatial variations in its cross-sectional area. A model of the middle ear (ME) and cochlea terminated the ear-canal model, which permitted estimation of ME efficiency. Acoustic measurements of ZEC were made at two probe locations in 15 normal-hearing subjects. ZEC was sensitive to measurement location, especially near frequencies of canal resonances and anti-resonances. Transforming ZEC to ZED reduced the influence of the canal, decreasing insertion-depth sensitivity of ZED between 1 and 12 kHz compared to ZEC. Absorbance, A, was less sensitive to probe placement than ZEC, but more sensitive than ZED above 5 kHz. ZED and A were similarly insensitive to probe placement between 1 and 5 kHz. The probe-placement sensitivity of ZED below 1 kHz was not reduced from that of either A or ZEC. ME efficiency had a bandpass shape with greatest efficiency between 1 and 4 kHz. Estimates of ZED and ME efficiency could extend the diagnostic capability of wideband-acoustic immittance measurements.

Compensating for ear-canal acoustics when measuring otoacoustic emissions

PubMed Central

Charaziak, Karolina K.; Shera, Christopher A.

2017-01-01

Otoacoustic emissions (OAEs) provide an acoustic fingerprint of the inner ear, and changes in this fingerprint may indicate changes in cochlear function arising from efferent modulation, aging, noise trauma, and/or exposure to harmful agents. However, the reproducibility and diagnostic power of OAE measurements is compromised by the variable acoustics of the ear canal, in particular, by multiple reflections and the emergence of standing waves at relevant frequencies. Even when stimulus levels are controlled using methods that circumvent standing-wave problems (e.g., forward-pressure-level calibration), distortion-product otoacoustic emission (DPOAE) levels vary with probe location by 10–15 dB near half-wave resonant frequencies. The method presented here estimates the initial outgoing OAE pressure wave at the eardrum from measurements of the conventional OAE, allowing one to separate the emitted OAE from the many reflections trapped in the ear canal. The emitted pressure level (EPL) represents the OAE level that would be recorded were the ear canal replaced by an infinite tube with no reflections. When DPOAEs are expressed using EPL, their variation with probe location decreases to the test–retest repeatability of measurements obtained at similar probe positions. EPL provides a powerful way to reduce the variability of OAE measurements and improve their ability to detect cochlear changes. PMID:28147590

Auricular Split-Thickness Skin Graft for Ear Canal Coverage.

PubMed

Haidar, Yarah M; Walia, Sartaaj; Sahyouni, Ronald; Ghavami, Yaser; Lin, Harrison W; Djalilian, Hamid R

2016-12-01

Split-thickness skin graft (STSG) continues to be the preferred means of external auditory canal (EAC) reconstruction. We thus sought to describe our experience using skin from the posterior aspect of the auricle (SPAA) as a donor site in EAC reconstruction. Grafts were, on average, 5 × 10 mm in size and obtained with a No. 10 blade after tumescence injection. The cases of 39 patients who underwent 41 procedures were retrospectively reviewed. Of the 38 patients with both 3- and 6-month follow-ups, no postoperative stenosis or bony exposure occurred. STSG from the SPAA can be a good option in EAC reconstruction. Total EAC/tympanic membrane coverage can be obtained with STSG from the SPAA. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2016.

Air-Leak Effects on Ear-Canal Acoustic Absorbance

PubMed Central

Rasetshwane, Daniel M.; Kopun, Judy G.; Gorga, Michael P.; Neely, Stephen T.

2015-01-01

Objective: Accurate ear-canal acoustic measurements, such as wideband acoustic admittance, absorbance, and otoacoustic emissions, require that the measurement probe be tightly sealed in the ear canal. Air leaks can compromise the validity of the measurements, interfere with calibrations, and increase variability. There are no established procedures for determining the presence of air leaks or criteria for what size leak would affect the accuracy of ear-canal acoustic measurements. The purpose of this study was to determine ways to quantify the effects of air leaks and to develop objective criteria to detect their presence. Design: Air leaks were simulated by modifying the foam tips that are used with the measurement probe through insertion of thin plastic tubing. To analyze the effect of air leaks, acoustic measurements were taken with both modified and unmodified foam tips in brass-tube cavities and human ear canals. Measurements were initially made in cavities to determine the range of critical leaks. Subsequently, data were collected in ears of 21 adults with normal hearing and normal middle-ear function. Four acoustic metrics were used for predicting the presence of air leaks and for quantifying these leaks: (1) low-frequency admittance phase (averaged over 0.1–0.2 kHz), (2) low-frequency absorbance, (3) the ratio of compliance volume to physical volume (CV/PV), and (4) the air-leak resonance frequency. The outcome variable in this analysis was the absorbance change (Δabsorbance), which was calculated in eight frequency bands. Results: The trends were similar for both the brass cavities and the ear canals. ΔAbsorbance generally increased with air-leak size and was largest for the lower frequency bands (0.1–0.2 and 0.2–0.5 kHz). Air-leak effects were observed in frequencies up to 10 kHz, but their effects above 1 kHz were unpredictable. These high-frequency air leaks were larger in brass cavities than in ear canals. Each of the four predictor variables exhibited consistent dependence on air-leak size. Low-frequency admittance phase and CV/PV decreased, while low-frequency absorbance and the air-leak resonance frequency increased. Conclusion: The effect of air leaks can be significant when their equivalent diameter exceeds 0.01 in. The observed effects were greatest at low frequencies where air leaks caused absorbance to increase. Recommended criteria for detecting air leaks include the following: when the frequency range of interest extends as low as 0.1 kHz, low-frequency absorbance should be ≤0.20 and low-frequency admittance phase ≥61 degrees. For frequency ranges as low as 0.2 kHz, low-frequency absorbance should be ≤0.29 and low-frequency admittance phase ≥44 degrees. PMID:25170779

Air-leak effects on ear-canal acoustic absorbance.

PubMed

Groon, Katherine A; Rasetshwane, Daniel M; Kopun, Judy G; Gorga, Michael P; Neely, Stephen T

2015-01-01

Accurate ear-canal acoustic measurements, such as wideband acoustic admittance, absorbance, and otoacoustic emissions, require that the measurement probe be tightly sealed in the ear canal. Air leaks can compromise the validity of the measurements, interfere with calibrations, and increase variability. There are no established procedures for determining the presence of air leaks or criteria for what size leak would affect the accuracy of ear-canal acoustic measurements. The purpose of this study was to determine ways to quantify the effects of air leaks and to develop objective criteria to detect their presence. Air leaks were simulated by modifying the foam tips that are used with the measurement probe through insertion of thin plastic tubing. To analyze the effect of air leaks, acoustic measurements were taken with both modified and unmodified foam tips in brass-tube cavities and human ear canals. Measurements were initially made in cavities to determine the range of critical leaks. Subsequently, data were collected in ears of 21 adults with normal hearing and normal middle-ear function. Four acoustic metrics were used for predicting the presence of air leaks and for quantifying these leaks: (1) low-frequency admittance phase (averaged over 0.1-0.2 kHz), (2) low-frequency absorbance, (3) the ratio of compliance volume to physical volume (CV/PV), and (4) the air-leak resonance frequency. The outcome variable in this analysis was the absorbance change (Δabsorbance), which was calculated in eight frequency bands. The trends were similar for both the brass cavities and the ear canals. ΔAbsorbance generally increased with air-leak size and was largest for the lower frequency bands (0.1-0.2 and 0.2-0.5 kHz). Air-leak effects were observed in frequencies up to 10 kHz, but their effects above 1 kHz were unpredictable. These high-frequency air leaks were larger in brass cavities than in ear canals. Each of the four predictor variables exhibited consistent dependence on air-leak size. Low-frequency admittance phase and CV/PV decreased, while low-frequency absorbance and the air-leak resonance frequency increased. The effect of air leaks can be significant when their equivalent diameter exceeds 0.01 in. The observed effects were greatest at low frequencies where air leaks caused absorbance to increase. Recommended criteria for detecting air leaks include the following: when the frequency range of interest extends as low as 0.1 kHz, low-frequency absorbance should be ≤0.20 and low-frequency admittance phase ≥61 degrees. For frequency ranges as low as 0.2 kHz, low-frequency absorbance should be ≤0.29 and low-frequency admittance phase ≥44 degrees.

[Equivalent Lever Principle of Ossicular Chain and Amplitude Reduction Effect of Internal Ear Lymph].

PubMed

Zhao, Xiaoyan; Qin, Renjia

2015-04-01

This paper makes persuasive demonstrations on some problems about the human ear sound transmission principle in existing physiological textbooks and reference books, and puts forward the authors' view to make up for its literature. Exerting the knowledge of lever in physics and the acoustics theory, we come up with an equivalent simplified model of manubrium mallei which is to meet the requirements as the long arm of the lever. We also set up an equivalent simplified model of ossicular chain--a combination of levers of ossicular chain. We disassemble the model into two simple levers, and make full analysis and demonstration on them. Through the calculation and comparison of displacement amplitudes in both external auditory canal air and internal ear lymph, we may draw a conclusion that the key reason, which the sound displacement amplitude is to be decreased to adapt to the endurance limit of the basement membrane, is that the density and sound speed in lymph is much higher than those in the air.

[Manifestation of first branchial anomaly:56 cases reportrhinitis].

PubMed

Zhang, B; Chen, L S; Huang, S L; Liang, L; Wu, P N; Zhang, S Y; L, Z M; Liang, L

2016-09-05

Objective: To sum up and conclude manifestation of congenital first branchial anomaly(CFBCA). Method: The clinical data of 56 patients from 2005 to 2015 in our hospital were retrospective reviewed. Result: Manifestation:mass without pain(26.8%),repeated sore and discharge(71.4%),otological symptom(external auditory discharge､hearing loss,28.6%).Eleven cases bacterial sample showed positive result,and most of them show pseudomonas aeruginosa and staphylococcus aureus.Auricular endoscopy typically performed stricture of external auditory canal,cholesteatoma samples accumulated in ear canal,fistula at the conjunction of the bone and cartilage and tympanic membranous attachment.Typical performance of CT(MRI)was that there were cystic,lobulated or tubular abnormal shadow related with ear canal in Pochet's triangle area whose cyst wall or pipe wall could been enhanced in enhanced CT(MRI) scans,and part of that could be connected with skin.The statistical difference between type Oslen and Work and clinical characteristics( P <0.01),and the relationship between type Oslen and Work( P <0.01).Most of Work Ⅰ were cyst type,and these two type often had no infected symptom.Most of them were young patients.Most of Work Ⅱ were sinus and fistula type ,and these two type often had infected symptom.Most of them were teenagers.Part of patients of type Work Ⅱ showed tympanic membranous attachment. Conclusion: CFBCA was rare,and it is more common in young patients and often in left part.It always performed as mass without pain､repeated sore and discharge､external auditory discharge.Most of Work Ⅰ were cyst type,and these two type often had no infected symptom and most of them were young patients .Most of Work Ⅱ were sinus and fistula type,and these two type often had infected symptom and most of them were teenagers.Auricular endoscopy,CT,MRI could help make diagnose.Doctors clinical need to differentiate it with related diseases according to different manifestations. Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.

Comparative Assessment of Torso and Seat Mounted Restraint Systems using Manikins on the Horizontal Impulse Accelerator

DTIC Science & Technology

2017-11-01

rearward rotation of the head towards the back or shoulder blades ). The y- axis of the head runs from right ear canal to the left ear canal with...PERSON (Monitor) a. REPORT Unclassified b. ABSTRACT Unclassified c . THIS PAGE Unclassified Chris Burneka 19b. TELEPHONE NUMBER...92 APPENDIX C . SAMPLE DATA SHEETS

The frequency range of TMJ sounds.

PubMed

Widmalm, S E; Williams, W J; Djurdjanovic, D; McKay, D C

2003-04-01

There are conflicting opinions about the frequency range of temporomandibular joint (TMJ) sounds. Some authors claim that the upper limit is about 650 Hz. The aim was to test the hypothesis that TMJ sounds may contain frequencies well above 650 Hz but that significant amounts of their energy are lost if the vibrations are recorded using contact sensors and/or travel far through the head tissues. Time-frequency distributions of 172 TMJ clickings (three subjects) were compared between recordings with one microphone in the ear canal and a skin contact transducer above the clicking joint and between recordings from two microphones, one in each ear canal. The energy peaks of the clickings recorded with a microphone in the ear canal on the clicking side were often well above 650 Hz and always in a significantly higher area (range 117-1922 Hz, P < 0.05 or lower) than in recordings obtained with contact sensors (range 47-375 Hz) or in microphone recordings from the opposite ear canal (range 141-703 Hz). Future studies are required to establish normative frequency range values of TMJ sounds but need methods also capable of recording the high frequency vibrations.

Level dependence of distortion product otoacoustic emission phase is attributed to component mixing

PubMed Central

Abdala, Carolina; Dhar, Sumitrajit; Kalluri, Radha

2011-01-01

Distortion product otoacoustic emissions (DPOAEs) measured in the ear canal represent the vector sum of components produced at two regions of the basilar membrane by distinct cochlear mechanisms. In this study, the effect of stimulus level on the 2f1 − f2 DPOAE phase was evaluated in 22 adult subjects across a three-octave range. Level effects were examined for the mixed DPOAE signal measured in the ear canal and after unmixing components to assess level effects individually on the distortion (generated at the f1, f2 overlap) and reflection (at fdp) sources. Results show that ear canal DPOAE phase slope becomes steeper with decreasing level; however, component analysis further explicates this result, indicating that interference between DPOAE components (rather than a shift in mechanics related to distortion generation) drives the level dependence of DPOAE phase measured in the ear canal. The relative contribution from the reflection source increased with decreasing level, producing more component interference and, at times, a reflection-dominated response at the lowest stimulus levels. These results have implications for the use of DPOAE phase to study cochlear mechanics and for the potential application of DPOAE phase for clinical purposes. PMID:21568415

Are Patients with Spontaneous CSF Otorrhea and Superior Canal Dehiscence Congenitally Predisposed to Their Disorders?

PubMed

Stevens, Shawn M; Hock, Kiefer; Samy, Ravi N; Pensak, Myles L

2018-04-01

Objectives (1) Compare lateral skull base (LSB) height/thickness in patients with spontaneous cerebrospinal fluid otorrhea (CSF), superior canal dehiscence (SCD), acoustic neuromas (AN), and otosclerosis (OTO). (2) Perform correlations between age, body mass index (BMI), sex, and LSB height/thickness. Study Design Case series with chart review. Setting Tertiary referral center. Subjects and Methods Patients with CSF, SCD, AN, and OTO diagnosed from 2006 to 2016 were included if they had high-definition temporal bone computed tomography (CT) and absence of trauma, radiation, chronic ear disease, and/or congenital anomaly. CT-based measurements included LSB height/thickness and pneumatization rates overlaying the external auditory canal (EAC), tegmen tympani (TgT), perigeniculate region (PG), and internal auditory canal (IAC). LSB height/thickness, age, sex, and BMI were statistically correlated. In total, 256 patients and 493 ears (109 CSF, 115 SCD, 269 AN/OTO) were measured. Results Patients with CSF had significantly higher BMIs than the other groups ( P < .001). Patients with CSF and SCD had similar radiographic LSB phenotypes at most measured locations. Both groups exhibited a significantly lower LSB height compared to the AN and OTO groups (mean, 3.9-4.2 mm vs 4.9-5.6 mm; P < .001). Patients with CSF and SCD also demonstrated significantly lower pneumatization rates, as low as 17% to 23% overlaying the PG and IAC ( P < .001). There were no statistically significant correlations found between age, sex, BMI, and LSB height/thickness at any measurement location in any group. Conclusions Patients with CSF and SCD exhibit similar radiographic LSB phenotypes. Age, sex, and BMI do not significantly correlate with LSB height/thickness. These data support the theory that CSF and SCD arise via similar congenital pathoetiologic mechanisms.

Sclerosteosis involving the temporal bone: histopathologic aspects.

PubMed

Nager, G T; Hamersma, H

1986-01-01

Sclerosteosis is a rare, potentially lethal, autosomal recessive, progressive craniotubular sclerosing bone dysplasia with characteristic facial and skeletal features. The temporal bone changes include a marked increase in overall size, extensive sclerosis, narrowing of the external auditory canal, and severe constriction of the internal auditory meatus, fallopian canal, eustachian tube, and middle ear cleft. Attenuation of the bony canals of the 9th, 10th, and 11th cranial nerves, reduction in size of the internal carotid artery, and severe obliteration of the sigmoid sinus and jugular bulb also occur. Loss of hearing, generally bilateral, is a frequent symptom. It often manifests in early childhood and initially is expressed as sound conduction impairment. Later, a sensorineural hearing loss and loss of vestibular nerve function often develop. Impairment of facial nerve function is another feature occasionally present at birth. In the beginning, a unilateral intermittent facial weakness may occur which eventually progresses to a bilateral permanent facial paresis. The histologic examination of the temporal bones from a patient with sclerosteosis explains the mechanisms involved in the progressive impairment of sound conduction and loss of cochlear, vestibular, and facial nerve function. There is a decrease of the arterial blood supply to the brain and an obstruction of the venous drainage from it. The histopathology reveals the obstacles to decompression of the middle ear cleft, ossicular chain, internal auditory and facial canals, and the risks, and in many instances the contraindications, to such procedures. On the other hand, decompression of the sigmoid sinus and jugular bulb should be considered as an additional life-saving procedure in conjunction with the prophylactic craniotomy recommended in all adult patients.

Otx1 null mutant mice show partial segregation of sensory epithelia comparable to lamprey ears

NASA Technical Reports Server (NTRS)

Fritzsch, B.; Signore, M.; Simeone, A.

2001-01-01

We investigated the development of inner ear innervation in Otx1 null mutants, which lack a horizontal canal, between embryonic day 12 (E12) and postnatal day 7 (P7) with DiI and immunostaining for acetylated tubulin. Comparable to control animals, horizontal crista-like fibers were found to cross over the utricle in Otx1 null mice. In mutants these fibers extend toward an area near the endolymphatic duct, not to a horizontal crista. Most Otx1 null mutants had a small patch of sensory hair cells at this position. Measurement of the area of the utricular macula suggested it to be enlarged in Otx1 null mutants. We suggest that parts of the horizontal canal crista remain incorporated in the utricular sensory epithelium in Otx1 null mutants. Other parts of the horizontal crista appear to be variably segregated to form the isolated patch of hair cells identifiable by the unique fiber trajectory as representing the horizontal canal crista. Comparison with lamprey ear innervation reveals similarities in the pattern of innervation with the dorsal macula, a sensory patch of unknown function. SEM data confirm that all foramina are less constricted in Otx1 null mutants. We propose that Otx1 is not directly involved in sensory hair cell formation of the horizontal canal but affects the segregation of the horizontal canal crista from the utricle. It also affects constriction of the two main foramina in the ear, but not their initial formation. Otx1 is thus causally related to horizontal canal morphogenesis as well as morphogenesis of these foramina.

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

PubMed Central

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

Validation of normalized pulse volume in the outer ear as a simple measure of sympathetic activity using warm and cold pressor tests: towards applications in ambulatory monitoring.

PubMed

Lee, Jihyoung; Matsumura, Kenta; Yamakoshi, Takehiro; Rolfe, Peter; Tanaka, Naoto; Kim, Kyungho; Yamakoshi, Ken-ichi

2013-03-01

Normalized pulse volume (NPV) derived from the ear has the potential to be a practical index for monitoring daily life stress. However, ear NPV has not yet been validated. Therefore, we compared NPV derived from an index finger using transmission photoplethysmography as a reference, with NPV derived from a middle finger and four sites of the ear using reflection photoplethysmography during baseline and while performing cold and warm water immersion in ten young and six middle-aged subjects. The results showed that logarithmically-transformed NPV (lnNPV) during cold water immersion as compared with baseline values was significantly lower, only at the index finger, the middle finger and the bottom of the ear-canal. Furthermore, lnNPV reactivities (ΔlnNPV; the difference between baseline and test values) from an index finger were significantly related to ΔlnNPV from the middle finger and the bottom of the ear-canal (young: r = 0.90 and 0.62, middle-aged: r = 0.80 and 0.58, respectively). In conclusion, these findings show that reflection and transmission photoplethysmography are comparable methods to derive NPV in accordance with our theoretical prediction. NPV derived from the bottom of the ear-canal is a valid approach, which could be useful for evaluating daily life stress.

Measurements of Human Middle- and Inner-Ear Mechanics With Dehiscence of the Superior Semicircular Canal

PubMed Central

Chien, Wade; Ravicz, Michael E.; Rosowski, John J.; Merchant, Saumil N.

2008-01-01

Objectives (1) To develop a cadaveric temporal-bone preparation to study the mechanism of hearing loss resulting from superior semicircular canal dehiscence (SCD) and (2) to assess the potential usefulness of clinical measurements of umbo velocity for the diagnosis of SCD. Background The syndrome of dehiscence of the superior semicircular canal is a clinical condition encompassing a variety of vestibular and auditory symptoms, including an air-bone gap at low frequencies. It has been hypothesized that the dehiscence acts as a “third window” into the inner ear that shunts acoustic energy away from the cochlea at low frequencies, causing hearing loss. Methods Sound-induced stapes, umbo, and round-window velocities were measured in prepared temporal bones (n = 8) using laser-Doppler vibrometry (1) with the superior semicircular canal intact, (2) after creation of a dehiscence in the superior canal, and (3) with the dehiscence patched. Clinical measurements of umbo velocity in live SCD ears (n = 29) were compared with similar data from our cadaveric temporal-bone preparations. Results An SCD caused a significant reduction in sound-induced round-window velocity at low frequencies, small but significant increases in sound-induced stapes and umbo velocities, and a measurable fluid velocity inside the dehiscence. The increase in sound-induced umbo velocity in temporal bones was also found to be similar to that measured in the 29 live ears with SCD. Conclusion Findings from the cadaveric temporal-bone preparation were consistent with the third-window hypothesis. In addition, measurement of umbo velocity in live ears is helpful in distinguishing SCD from other otologic pathologies presenting with an air-bone gap (e.g., otosclerosis). PMID:17255894

A microbiome case-control study of recurrent acute otitis media identified potentially protective bacterial genera.

PubMed

Lappan, Rachael; Imbrogno, Kara; Sikazwe, Chisha; Anderson, Denise; Mok, Danny; Coates, Harvey; Vijayasekaran, Shyan; Bumbak, Paul; Blyth, Christopher C; Jamieson, Sarra E; Peacock, Christopher S

2018-02-20

Recurrent acute otitis media (rAOM, recurrent ear infection) is a common childhood disease caused by bacteria termed otopathogens, for which current treatments have limited effectiveness. Generic probiotic therapies have shown promise, but seem to lack specificity. We hypothesised that healthy children with no history of AOM carry protective commensal bacteria that could be translated into a specific probiotic therapy to break the cycle of re-infection. We characterised the nasopharyngeal microbiome of these children (controls) in comparison to children with rAOM (cases) to identify potentially protective bacteria. As some children with rAOM do not appear to carry any of the known otopathogens, we also hypothesised that characterisation of the middle ear microbiome could identify novel otopathogens, which may also guide the development of more effective therapies. Middle ear fluids, middle ear rinses and ear canal swabs from the cases and nasopharyngeal swabs from both groups underwent 16S rRNA gene sequencing. The nasopharyngeal microbiomes of cases and controls were distinct. We observed a significantly higher abundance of Corynebacterium and Dolosigranulum in the nasopharynx of controls. Alloiococcus, Staphylococcus and Turicella were abundant in the middle ear and ear canal of cases, but were uncommon in the nasopharynx of both groups. Gemella and Neisseria were characteristic of the case nasopharynx, but were not prevalent in the middle ear. Corynebacterium and Dolosigranulum are characteristic of a healthy nasopharyngeal microbiome. Alloiococcus, Staphylococcus and Turicella are possible novel otopathogens, though their rarity in the nasopharynx and prevalence in the ear canal means that their role as normal aural flora cannot be ruled out. Gemella and Neisseria are unlikely to be novel otopathogens as they do not appear to colonise the middle ear in children with rAOM.

Computed tomography demonstrates abnormalities of contralateral ear in subjects with unilateral sensorineural hearing loss.

PubMed

Marcus, Sonya; Whitlow, Christopher T; Koonce, James; Zapadka, Michael E; Chen, Michael Y; Williams, Daniel W; Lewis, Meagan; Evans, Adele K

2014-02-01

Prior studies have associated gross inner ear abnormalities with pediatric sensorineural hearing loss (SNHL) using computed tomography (CT). No studies to date have specifically investigated morphologic inner ear abnormalities involving the contralateral unaffected ear in patients with unilateral SNHL. The purpose of this study is to evaluate contralateral inner ear structures of subjects with unilateral SNHL but no grossly abnormal findings on CT. IRB-approved retrospective analysis of pediatric temporal bone CT scans. 97 temporal bone CT scans, previously interpreted as "normal" based upon previously accepted guidelines by board certified neuroradiologists, were assessed using 12 measurements of the semicircular canals, cochlea and vestibule. The control-group consisted of 72 "normal" temporal bone CTs with underlying SNHL in the subject excluded. The study-group consisted of 25 normal-hearing contralateral temporal bones in subjects with unilateral SNHL. Multivariate analysis of covariance (MANCOVA) was then conducted to evaluate for differences between the study and control group. Cochlea basal turn lumen width was significantly greater in magnitude and central lucency of the lateral semicircular canal bony island was significantly lower in density for audiometrically normal ears of subjects with unilateral SNHL compared to controls. Abnormalities of the inner ear were present in the contralateral audiometrically normal ears of subjects with unilateral SNHL. These data suggest that patients with unilateral SNHL may have a more pervasive disease process that results in abnormalities of both ears. The findings of a cochlea basal turn lumen width disparity >5% from "normal" and/or a lateral semicircular canal bony island central lucency disparity of >5% from "normal" may indicate inherent risk to the contralateral unaffected ear in pediatric patients with unilateral sensorineural hearing loss. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Treatment and Prognosis of Squamous Cell Carcinoma of the External Auditory Canal and Middle Ear: A Multi-Institutional Retrospective Review of 87 Patients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ogawa, Kazuhiko; Nakamura, Katsumasa; Hatano, Kazuo

Purpose: To examine the relative roles of surgery, radiotherapy, and chemotherapy in the management of patients with squamous cell carcinomas of the external auditory canal and middle ear. Methods and Materials: The records of 87 patients with histologically confirmed squamous cell carcinoma who were treated between 1984 and 2005 were reviewed. Fifty-three patients (61%) were treated with surgery and radiotherapy (S + RT group) and the remaining 34 patients with radiotherapy alone (RT group). Chemotherapy was administered in 34 patients (39%). Results: The 5-year actuarial overall and disease-free survival (DFS) rates for all patients were 55% and 54%, respectively. Onmore » univariate analysis, T stage (Stell's classification), treatment modality, and Karnofsky performance status had significant impact on DFS. On multivariate analysis, T stage and treatment modality were significant prognostic factors. Chemotherapy did not influence DFS. The 5-year DFS rate in T1, T2, and T3 patients was 83%, 45%, and 0 in the RT group (p < 0.0001) and 75%, 75%, and 46% in the S + RT group (p = 0.13), respectively. The 5-year DFS rate in patients with negative surgical margins, those with positive margins, and those with macroscopic residual disease was 83%, 55%, and 38%, respectively (p = 0.007). Conclusions: Radical radiotherapy is the treatment of choice for early-stage (T1) diseases, whereas surgery (negative surgical margins if possible) with radiotherapy is recommended as the standard care for advanced (T2-3) disease. Further clarification on the role of chemotherapy is necessary.« less

Comparison of clinical outcomes of three different packing materials in the treatment of severe acute otitis externa.

PubMed

Demir, D; Yılmaz, M S; Güven, M; Kara, A; Elden, H; Erkorkmaz, Ü

2018-06-13

To analyse the clinical outcomes of biodegradable synthetic polyurethane foam versus ribbon gauze and ear wick in the treatment of severe acute otitis externa. Ninety-two adults with severe acute otitis externa were randomly assigned to groups receiving ear wick (n = 28), ribbon gauze (n = 34) or biodegradable synthetic polyurethane foam (n = 30). Clinical efficacy, in terms of otalgia, oedema, erythema and tenderness of the external auditory canal, was assessed before packing was applied and at follow up on the 3rd and 7th days of presentation. All packing materials were associated with improved otalgia and oedema on the 3rd day; however, there were significant differences between biodegradable synthetic polyurethane foam and the other packing materials, and there was no significant reduction in tenderness in the biodegradable synthetic polyurethane foam group on the 3rd day. In the ribbon gauze and ear wick groups, improvements in all clinical efficacy scores were statistically significant for all pairwise comparisons. The three packing materials were all quite effective in treating severe acute otitis externa, but ear wick and ribbon gauze were superior to biodegradable synthetic polyurethane foam for relieving signs and symptoms, especially on the 3rd day.

Mastoid Cavity Dimensions and Shape: Method of Measurement and Virtual Fitting of Implantable Devices

PubMed Central

Handzel, Ophir; Wang, Haobing; Fiering, Jason; Borenstein, Jeffrey T.; Mescher, Mark J.; Leary Swan, Erin E.; Murphy, Brian A.; Chen, Zhiqiang; Peppi, Marcello; Sewell, William F.; Kujawa, Sharon G.; McKenna, Michael J.

2009-01-01

Temporal bone implants can be used to electrically stimulate the auditory nerve, to amplify sound, to deliver drugs to the inner ear and potentially for other future applications. The implants require storage space and access to the middle or inner ears. The most acceptable space is the cavity created by a canal wall up mastoidectomy. Detailed knowledge of the available space for implantation and pathways to access the middle and inner ears is necessary for the design of implants and successful implantation. Based on temporal bone CT scans a method for three-dimensional reconstruction of a virtual canal wall up mastoidectomy space is described. Using Amira® software the area to be removed during such surgery is marked on axial CT slices, and a three-dimensional model of that space is created. The average volume of 31 reconstructed models is 12.6 cm3 with standard deviation of 3.69 cm3, ranging from 7.97 to 23.25 cm3. Critical distances were measured directly from the model and their averages were calculated: height 3.69 cm, depth 2.43 cm, length above the external auditory canal (EAC) 4.45 cm and length posterior to EAC 3.16 cm. These linear measurements did not correlate well with volume measurements. The shape of the models was variable to a significant extent making the prediction of successful implantation for a given design based on linear and volumetric measurement unreliable. Hence, to assure successful implantation, preoperative assessment should include a virtual fitting of an implant into the intended storage space. The above-mentioned three-dimensional models were exported from Amira to a Solidworks application where virtual fitting was performed. Our results are compared to other temporal bone implant virtual fitting studies. Virtual fitting has been suggested for other human applications. PMID:19372649

Characterizing the ear canal acoustic reflectance and impedance by pole-zero fitting

PubMed Central

Robinson, Sarah R.; Nguyen, Cac T.; Allen, Jont B.

2013-01-01

This study characterizes middle ear complex acoustic reflectance (CAR) and impedance by fitting poles and zeros to real-ear measurements. The goal of this work is to establish a quantitative connection between pole-zero locations and the underlying physical properties of CAR data. Most previous studies have analyzed CAR magnitude; while the magnitude accounts for reflected power, it does not encode latency information. Thus, an analysis that studies the real and imaginary parts of the data together could be more powerful. Pole-zero fitting of CAR data is examined using data compiled from various studies, dating back to Voss and Allen (1994). Recent CAR measurements were taken using a middle ear acoustic power analyzer (MEPA) system (HearID, Mimosa Acoustics), which makes complex acoustic impedance and reflectance measurements in the ear canal over the 0.2 to 6.0 kHz frequency range. Pole-zero fits to measurements over this range are achieved with an average RMS relative error of less than 3% using 12 poles. Factoring the reflectance fit into its all-pass and minimum-phase components approximates the effect of the ear canal, allowing for comparison across measurements. It was found that individual CAR magnitude variations for normal middle ears in the 1 to 4 kHz range often give rise to closely-placed pole-zero pairs, and that the locations of the poles and zeros in the s-plane may differ between normal and pathological middle ears. This study establishes a methodology for examining the physical and mathematical properties of CAR using a concise parametric model. Pole-zero modeling shows promise for precise parameterization of CAR data and for identification of middle ear pathologies. PMID:23524141

SQUAMOUS CELL CARCINOMA IN TWO SNOW LEOPARDS (UNCIA UNCIA) WITH UNUSUAL AURICULAR PRESENTATION.

PubMed

Quintard, Benoît; Greunz, Eva Maria; Lefaux, Brice; Lemberger, Karin; Leclerc, Antoine

2017-06-01

Squamous cell carcinoma (SCC) is well documented in snow leopards ( Uncia uncia ) and most common locations are oral, facial, or pedal. These two cases illustrate an unusual auricular presentation, which is more often reported in white domestic cats. The animals were aged and presented clinical signs of otitis such as head shaking and ear scratching. Clinical examinations showed auricular canal masses with chronic purulent otitis. In both cases, clinical deterioration led to euthanasia and histology of the ear canal was consistent with SCC and showed numerous vascular emboli. These cases illustrate an unreported aggressive localization for SCC in snow leopards, which should be included in the differential diagnosis of otitis in this species. Auricular SCC may be underdiagnosed as the ear canal is infrequently sampled for histopathology. This auricular localization should be considered when metastases are found upon necropsy without internal primary tumor.

Computed tomographic findings in 205 dogs with clinical signs compatible with middle ear disease: a retrospective study.

PubMed

Belmudes, Audrey; Pressanti, Charline; Barthez, Paul Y; Castilla-Castaño, Eloy; Fabries, Lionel; Cadiergues, Marie C

2018-02-01

Computed tomography (CT) is considered to be the reference method to evaluate middle ear structures. To evaluate the presence and severity of CT changes in the middle ear and establish if any specific clinical presentations are associated with otitis media. Medical records of animals referred for CT with history and clinical signs consistent with middle ear disease. Retrospective evaluation of CT examinations of tympanic bullae performed over a six year period. Medical records were reviewed for signalment, clinical signs and cytological evaluation of the external ear canal. Dogs were divided into three clinical groups: chronic otitis externa (Group 1), peripheral vestibular disorder (Group 2) and other clinical presentations (Group 3). Group 1 - Of 214 ears, 87 (40.7%) had CT abnormalities: 38 of 87 (17.7%) had material-filled bullae, 42 of 87 (19.6%) had thickened bullae walls and seven of 87 (3.2%) had lysis of the bulla. Abnormalities were significantly more frequent in dogs with suppurative otitis than in erythemato-ceruminous otitis (57% and 23%, respectively; P = 0.003). Proliferative otitis, particularly in French bulldogs, was associated with severe otitis media. Group 2 - Of the 106 ears, 91 (85.8%) had normal tympanic bullae. Group 3 - Of the 26 ears from deaf dogs, 17 had filled bullae; all nine affected dogs were Cavalier King Charles spaniels. All dogs with Claude Bernard Horner syndrome or head tilt had normal tympanic bullae. CT is useful for canine chronic otitis externa, particularly in suppurative or proliferative otitis, even in the absence of associated neurological signs. © 2017 ESVD and ACVD.

"Epic Ear Defence"-A Game to Educate Children on the Risks of Noise-Related Hearing Loss.

PubMed

Eikelboom, Robert H; Leishman, Natalie F; Munro, Tyler J; Nguyen, Bach; Riggs, Peter R; Tennant, Jonathon; West, Rhiannon K; Robertson, William B

2012-12-01

Hearing loss resulting from overexposure to entertainment-related sounds is a modern concern. "Epic Ear Defence" places the player in the three-dimensional environment of the ear canal and challenges the player to defend the ear from various noises, to delay the onset of noise-related hearing loss.

PubMed Central

Presutti, L.; Bonali, M.; Marchioni, D.; Pavesi, G.; Feletti, A.; Alicandri-Ciufelli, M.

2017-01-01

SUMMARY The aim of this paper is to describe and evaluate the feasibility of an expanded endoscopic transcanal transpromotorial approach (ExpTTA) to the internal auditory canal and the cerebellopontine angle. To this end, we performed a cadaveric dissection study in September 2015. In total, 2 heads (4 sides) were dissected focusing on anatomical landmarks and surgical feasibility. Data from dissections were reviewed and analysed for further consideration. In all 4 sides of the cadavers the procedure was feasible. In all cadavers, it was necessary to extensively drill the temporo-mandibular joint and to calibrate the external ear canal to allow adequate room to manoeuver the instruments and optics and to comfortably access the cerebellopontine angle. In addition, thorough skeletonisation of the carotid artery and the jugular bulb were necessary for the same purpose. In conclusion, ExpTTA appeared to be successful to access the internal auditory canal and cerebellopontine angle region. Potential extensive and routine application of this type of approach in lateral skull base surgery will depend on the development of technology and surgical refinements and on the diffusion of skull base endoscopic skills among otolaryngologists and neurosurgical community. PMID:28516966

[Recent advances in research on Malassezia microbiota in humans].

PubMed

Sugita, Takashi; Zhang, Enshi; Tanaka, Takafumi; Nishikawa, Akemi; Tajima, Mami; Tsuboi, Ryoji

2013-01-01

Malassezia species of lipophilic yeasts account for most fungal microbiota. Although they colonize healthy skin, they are also associated with several skin diseases, including pityriasis versicolor, seborrheic dermatitis, Malassezia folliculitis, and atopic dermatitis. To date, 14 members of the Malassezia genus have been identified. Of these, both M. globosa and M. restricta predominate, regardless of skin-disease type. Comprehensive analysis of fungal microbiota in the skin of patients with atopic dermatitis using an rRNA clone library method revealed that fungal microbiota cluster according to disease severity. The external ear canal and sole of the foot are colonized by specific Malassezia microbiota.

Shape and 3D acoustically induced vibrations of the human eardrum characterized by digital holography

NASA Astrophysics Data System (ADS)

Khaleghi, Morteza; Furlong, Cosme; Cheng, Jeffrey Tao; Rosowski, John J.

2014-07-01

The eardrum or Tympanic Membrane (TM) transfers acoustic energy from the ear canal (at the external ear) into mechanical motions of the ossicles (at the middle ear). The acousto-mechanical-transformer behavior of the TM is determined by its shape and mechanical properties. For a better understanding of hearing mysteries, full-field-of-view techniques are required to quantify shape, nanometer-scale sound-induced displacement, and mechanical properties of the TM in 3D. In this paper, full-field-of-view, three-dimensional shape and sound-induced displacement of the surface of the TM are obtained by the methods of multiple wavelengths and multiple sensitivity vectors with lensless digital holography. Using our developed digital holographic systems, unique 3D information such as, shape (with micrometer resolution), 3D acoustically-induced displacement (with nanometer resolution), full strain tensor (with nano-strain resolution), 3D phase of motion, and 3D directional cosines of the displacement vectors can be obtained in full-field-ofview with a spatial resolution of about 3 million points on the surface of the TM and a temporal resolution of 15 Hz.

Ear emergencies

MedlinePlus

... and ruptured eardrums can be caused by: Inserting cotton swabs, toothpicks, pins, pens, or other objects into ... The person will have severe pain. Place sterile cotton gently in the outer ear canal to keep ...

Bilateral tympanokeratomas (cholesteatomas) with bilateral otitis media, unilateral otitis interna and acoustic neuritis in a dog.

PubMed

Østevik, Liv; Rudlang, Kathrine; Holt Jahr, Tuva; Valheim, Mette; Njaa, Bradley Lyndon

2018-05-22

An aural cholesteatoma, more appropriately named tympanokeratoma, is an epidermoid cyst of the middle ear described in several species, including dogs, humans and Mongolian gerbils. The cyst lining consists of stratified, keratinizing squamous epithelium with central accumulation of a keratin debris. This case report describes vestibular ganglioneuritis and perineuritis in a dog with chronic otitis, bilateral tympanokeratomas and presumed extension of otic infection to the central nervous system. An 11-year-old intact male Dalmatian dog with chronic bilateral otitis externa and sudden development of symptoms of vestibular disease was examined. Due to the dog's old age the owner opted for euthanasia without any further examination or treatment and the dog was submitted for necropsy. Transection of the ears revealed grey soft material in the external ear canals and pearly white, dry material consistent with keratin in the tympanic bullae bilaterally. The brain and meninges were grossly unremarkable. Microscopical findings included bilateral otitis externa and media, unilateral otitis interna, ganglioneuritis and perineuritis of the spiral ganglion of the vestibulocochlear nerve and multifocal to coalescing, purulent meningitis. A keratinizing squamous epithelial layer continuous with the external acoustic meatus lined the middle ear compartments, consistent with bilateral tympanokeratomas. Focal bony erosion of the petrous portion of the temporal bone and squamous epithelium and Gram-positive bacterial cocci were evident in the left cochlea. The findings suggest that meningitis developed secondary to erosion of the temporal bone and ganglioneuritis and/or perineuritis of the vestibulocochlear nerve. Middle ear tympanokeratoma is an important and potentially life-threatening otic condition in the dog. Once a tympanokeratoma has developed expansion of the cyst can lead to erosion of bone and extension of otic infection to the inner ear, vestibulocochlear ganglion and nerve potentially leading to bacterial infection of the central nervous system.

Guide to Understanding Pfeiffer Syndrome

MedlinePlus

... sockets (orbits). Approximately 50% of children with Pfeiffer syndrome have some form of hearing loss secondary to an abnormally small ear canal and middle ear. Dental problems are also common. Visual problems ...

Exposure to non-ionizing electromagnetic fields emitted from mobile phones induced DNA damage in human ear canal hair follicle cells.

PubMed

Akdag, Mehmet; Dasdag, Suleyman; Canturk, Fazile; Akdag, Mehmet Zulkuf

2018-01-01

The aim of this study was to investigate effect of radiofrequency radiation (RFR) emitted from mobile phones on DNA damage in follicle cells of hair in the ear canal. The study was carried out on 56 men (age range: 30-60 years old)in four treatment groups with n = 14 in each group. The groups were defined as follows: people who did not use a mobile phone (Control), people use mobile phones for 0-30 min/day (second group), people use mobile phones for 30-60 min/day (third group) and people use mobile phones for more than 60 min/day (fourth group). Ear canal hair follicle cells taken from the subjects were analyzed by the Comet Assay to determine DNA damages. The Comet Assay parameters measured were head length, tail length, comet length, percentage of head DNA, tail DNA percentage, tail moment, and Olive tail moment. Results of the study showed that DNA damage indicators were higher in the RFR exposure groups than in the control subjects. In addition, DNA damage increased with the daily duration of exposure. In conclusion, RFR emitted from mobile phones has a potential to produce DNA damage in follicle cells of hair in the ear canal. Therefore, mobile phone users have to pay more attention when using wireless phones.

Otologic Manifestations of Autosomal Recessive Congenital Ichthyosis in Children.

PubMed

Martín-Santiago, A; Rodríguez-Pascual, M; Knöpfel, N; Hernández-Martín, Á

2015-11-01

Few studies have investigated ear involvement in nonsyndromic autosomal recessive congenital ichthyosis (ARCI). To assess the type and frequency of otologic manifestations of ARCI in patients under follow-up at the pediatric dermatology department of our hospital. We prospectively studied the presence of ear pain, ear itching, tinnitus, otitis, cerumen impaction, accumulation of epithelial debris, and hearing loss. Daily hygiene measures, topical treatments, medical-surgical interventions, and frequency of visits to an ear, nose, and throat (ENT) specialist were noted in the patients' medical records. Ear examination and hearing tests were performed in all cases. Ten patients were studied: 2 had a self-healing collodion baby phenotype and 8 had ichthyosis. There was mention of otologic manifestations in the records of all 8 patients with ichthyosis (100%); 6 of these patients (75%) had abnormalities in the external auditory canal examination and 2 (25%) had conductive hearing loss. Our findings are limited by the small number of patients studied, all of whom were younger than 19 years. The involvement of both dermatologists and ENT specialists in the management of patients with ichthyosis is crucial to ensure the application of the best therapeutic and preventive measures. More studies are needed to assess the prevalence and impact on quality of life of ear involvement in patients with ichthyosis and to determine the optimal interval between ENT visits for these patients. Copyright © 2015 Elsevier España, S.L.U. and AEDV. All rights reserved.

Hair band retained prosthetic reconstruction of bilaterally missing ears: a case of congenital atresia of external auditory canals and pinna.

PubMed

Minati, C; Shanmuganathan, N; Jain, Bhakti S; Padmanabhan, T V

2014-01-01

Auricular defects present reconstructive challenges, especially if they are bilateral. Surgical reconstruction provides effective results for defects; however for some patients surgical intervention is contraindicated. This case report describes an easy clinical technique to rehabilitate a patient with auricular defects. The prime purpose of this treatment rendered was to restore the lost auricular structure to the patient's satisfaction in an elegant, comfortable and cost effective manner. A thirteen year old female patient, who had bilaterally missing ears, was referred with a chief complaint of discomfort caused due to her existing hair band prosthesis and unsatisfactory esthetics. There was constant formation of ulcers at the site where the prosthesis came in contact with the skin. Considering the patient's age, ease of use and economic status, hair band retained ear prosthesis was selected. Silicone ear prostheses were fabricated on acrylic substructure to ensure fit, esthetics. Beneath the acrylic plates, a thin layer of soft silicone material was attached. The ear prostheses of both sides were connected with a metal hair band to retain. The newly fabricated prosthesis overcame the limitations of the existing one. The patient and her parents were satisfied with the results. The hair band retained silicone ear prosthesis is esthetic, economical and easy to use as a facial prosthesis. The addition of soft liner provided a cushion-like effect, thus reducing the formation of any ulcers due to pressure. Copyright © 2013 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

Meniere's Disease

MedlinePlus

... are recorded as warm and cool water or air are gently introduced into each ear canal. Since the eyes and ears work in coordination through the nervous system, measurement of eye movements can be used to test ...

Genetics Home Reference: Treacher Collins syndrome

MedlinePlus

... defects of the three small bones in the middle ear, which transmit sound, or by underdevelopment of the ear canal. People with Treacher Collins syndrome usually have normal intelligence. Related Information What does ...

Finite element modeling of acousto-mechanical coupling in the cat middle ear

PubMed Central

Tuck-Lee, James P.; Pinsky, Peter M.; Steele, Charles R.; Puria, Sunil

2008-01-01

The function of the middle ear is to transfer acoustic energy from the ear canal to the cochlea. An essential component of this system is the tympanic membrane. In this paper, a new finite element model of the middle ear of the domestic cat is presented, generated in part from cadaver anatomy via microcomputed tomographic imaging. This model includes a layered composite model of the eardrum, fully coupled with the acoustics in the ear canal and middle-ear cavities. Obtaining the frequency response from 100 Hz to 20 kHz is a computationally challenging task, which has been accomplished by using a new adaptive implementation of the reduced-order matrix Padé-via-Lanczos algorithm. The results are compared to established physiological data. The fully coupled model is applied to study the role of the collagen fiber sublayers of the eardrum and to investigate the relationship between the structure of the middle-ear cavities and its function. Three applications of this model are presented, demonstrating the shift in the middle-ear resonance due to the presence of the septum that divides the middle-ear cavity space, the significance of the radial fiber layer on high frequency transmission, and the importance of the transverse shear modulus in the eardrum microstructure. PMID:18646982

Human middle-ear model with compound eardrum and airway branching in mastoid air cells

PubMed Central

Keefe, Douglas H.

2015-01-01

An acoustical/mechanical model of normal adult human middle-ear function is described for forward and reverse transmission. The eardrum model included one component bound along the manubrium and another bound by the tympanic cleft. Eardrum components were coupled by a time-delayed impedance. The acoustics of the middle-ear cleft was represented by an acoustical transmission-line model for the tympanic cavity, aditus, antrum, and mastoid air cell system with variable amounts of excess viscothermal loss. Model parameters were fitted to published measurements of energy reflectance (0.25–13 kHz), equivalent input impedance at the eardrum (0.25–11 kHz), temporal-bone pressure in scala vestibuli and scala tympani (0.1–11 kHz), and reverse middle-ear impedance (0.25–8 kHz). Inner-ear fluid motion included cochlear and physiological third-window pathways. The two-component eardrum with time delay helped fit intracochlear pressure responses. A multi-modal representation of the eardrum and high-frequency modeling of the middle-ear cleft helped fit ear-canal responses. Input reactance at the eardrum was small at high frequencies due to multiple modal resonances. The model predicted the middle-ear efficiency between ear canal and cochlea, and the cochlear pressures at threshold. PMID:25994701

Human middle-ear model with compound eardrum and airway branching in mastoid air cells.

PubMed

Keefe, Douglas H

2015-05-01

An acoustical/mechanical model of normal adult human middle-ear function is described for forward and reverse transmission. The eardrum model included one component bound along the manubrium and another bound by the tympanic cleft. Eardrum components were coupled by a time-delayed impedance. The acoustics of the middle-ear cleft was represented by an acoustical transmission-line model for the tympanic cavity, aditus, antrum, and mastoid air cell system with variable amounts of excess viscothermal loss. Model parameters were fitted to published measurements of energy reflectance (0.25-13 kHz), equivalent input impedance at the eardrum (0.25-11 kHz), temporal-bone pressure in scala vestibuli and scala tympani (0.1-11 kHz), and reverse middle-ear impedance (0.25-8 kHz). Inner-ear fluid motion included cochlear and physiological third-window pathways. The two-component eardrum with time delay helped fit intracochlear pressure responses. A multi-modal representation of the eardrum and high-frequency modeling of the middle-ear cleft helped fit ear-canal responses. Input reactance at the eardrum was small at high frequencies due to multiple modal resonances. The model predicted the middle-ear efficiency between ear canal and cochlea, and the cochlear pressures at threshold.

Molecular biology of hearing

PubMed Central

Stöver, Timo; Diensthuber, Marc

2012-01-01

The inner ear is our most sensitive sensory organ and can be subdivided into three functional units: organ of Corti, stria vascularis and spiral ganglion. The appropriate stimulus for the organ of hearing is sound, which travels through the external auditory canal to the middle ear where it is transmitted to the inner ear. The inner ear houses the hair cells, the sensory cells of hearing. The inner hair cells are capable of mechanotransduction, the transformation of mechanical force into an electrical signal, which is the basic principle of hearing. The stria vascularis generates the endocochlear potential and maintains the ionic homeostasis of the endolymph. The dendrites of the spiral ganglion form synaptic contacts with the hair cells. The spiral ganglion is composed of neurons that transmit the electrical signals from the cochlea to the central nervous system. In recent years there has been significant progress in research on the molecular basis of hearing. An increasing number of genes and proteins related to hearing are being identified and characterized. The growing knowledge of these genes contributes not only to greater appreciation of the mechanism of hearing but also to a deeper understanding of the molecular basis of hereditary hearing loss. This basic research is a prerequisite for the development of molecular diagnostics and novel therapies for hearing loss. PMID:22558056

Ear-Canal Reflectance, Umbo Velocity and Tympanometry in Normal Hearing Adults

PubMed Central

Rosowski, John J; Nakajima, Hideko H.; Hamade, Mohamad A.; Mafoud, Lorice; Merchant, Gabrielle R.; Halpin, Christopher F.; Merchant, Saumil N.

2011-01-01

Objective This study compares measurements of ear-canal reflectance (ECR) to other objective measurements of middle-ear function including, audiometry, umbo velocity (VU), and tympanometry in a population of strictly defined normal hearing ears. Design Data were prospectively gathered from 58 ears of 29 normal hearing subjects, 16 female and 13 male, aged 22–64 years. Subjects met all of the following criteria to be considered as having normal hearing. (1) No history of significant middle-ear disease. (2) No history of otologic surgery. (3) Normal tympanic membrane (TM) on otoscopy. (4) Pure-tone audiometric thresholds of 20 dB HL or better for 0.25 – 8 kHz. (5) Air-bone gaps no greater than 15 dB at 0.25 kHz and 10 dB for 0.5 – 4 kHz. (6) Normal, type-A peaked tympanograms. (7) All subjects had two “normal” ears (as defined by these criteria). Measurements included pure-tone audiometry for 0.25 – 8 kHz, standard 226 Hz tympanometry, Ear canal reflectance(ECR) for 0.2 – 6 kHz at 60 dB SPL using the Mimosa Acoustics HearID system, and Umbo Velocity (VU ) for 0.3 – 6 kHz at 70–90 dB SPL using the HLV-1000 laser Doppler vibrometer (Polytec Inc). Results Mean power reflectance (|ECR|2) was near 1.0 at 0.2– 0.3 kHz, decreased to a broad minimum of 0.3 to 0.4 between 1 and 4 kHz, and then sharply increased to almost 0.8 by 6 kHz. The mean pressure reflectance phase angle (∠ECR) plotted on a linear frequency scale showed a group delay of approximately 0.1 ms for 0.2 – 6 kHz. Small significant differences were observed in |ECR|2 at the lowest frequencies between right and left ears, and between males and females at 4 kHz. |ECR|2 decreased with age, but reached significance only at 1 kHz. Our ECR measurements were generally similar to previous published reports. Highly significant negative correlations were found between |ECR|2 and VU for frequencies below 1 kHz. Significant correlations were also found between the tympanometrically determined peak total compliance and |ECR|2 and The results suggest that middle-ear compliance VU at frequencies below 1 kHz. contributes significantly to the measured power reflectance and umbo velocity at frequencies below 1 kHz, but not at higher frequencies. Conclusions This study has established a database of objective measurements of middle ear function (ear-canal reflectance, umbo velocity, tympanometry) in a population of strictly defined normal hearing ears. The data will promote our understanding of normal middle ear function, and will serve as a control for comparison to similar measurements made in pathological ears. PMID:21857517

Sheep as a large animal ear model: Middle-ear ossicular velocities and intracochlear sound pressure.

PubMed

Péus, Dominik; Dobrev, Ivo; Prochazka, Lukas; Thoele, Konrad; Dalbert, Adrian; Boss, Andreas; Newcomb, Nicolas; Probst, Rudolf; Röösli, Christof; Sim, Jae Hoon; Huber, Alexander; Pfiffner, Flurin

2017-08-01

Animals are frequently used for the development and testing of new hearing devices. Dimensions of the middle ear and cochlea differ significantly between humans and commonly used animals, such as rodents or cats. The sheep cochlea is anatomically more like the human cochlea in size and number of turns. This study investigated the middle-ear ossicular velocities and intracochlear sound pressure (ICSP) in sheep temporal bones, with the aim of characterizing the sheep as an experimental model for implantable hearing devices. Measurements were made on fresh sheep temporal bones. Velocity responses of the middle ear ossicles at the umbo, long process of the incus and stapes footplate were measured in the frequency range of 0.25-8 kHz using a laser Doppler vibrometer system. Results were normalized by the corresponding sound pressure level in the external ear canal (P EC ). Sequentially, ICSPs at the scala vestibuli and tympani were then recorded with custom MEMS-based hydrophones, while presenting identical acoustic stimuli. The sheep middle ear transmitted most effectively around 4.8 kHz, with a maximum stapes velocity of 0.2 mm/s/Pa. At the same frequency, the ICSP measurements in the scala vestibuli and tympani showed the maximum gain relative to the P EC (24 dB and 5 dB, respectively). The greatest pressure difference across the cochlear partition occurred between 4 and 6 kHz. A comparison between the results of this study and human reference data showed middle-ear resonance and best cochlear sensitivity at higher frequencies in sheep. In summary, sheep can be an appropriate large animal model for research and development of implantable hearing devices. Copyright © 2017 Elsevier B.V. All rights reserved.

Volumetric measurements of the inner ear in patients with Meniere's disease using three-dimensional magnetic resonance imaging.

PubMed

Inui, Hiroshi; Sakamoto, Tsuyoshi; Ito, Taeko; Kitahara, Tadashi

2016-09-01

This study described the lateralities of axial length of inner ear (ALIE), of the volume of inner ear (VIE) and age-related differences of the volume of inner ear components in patients with chronic rhinosinusitis (CRS). Age-related differences were found in ALIE and the positive correlation in ALIE and the volume of the cochlea (VC) of the affected ear in patients with Meniere's disease (MD). To identify side or sex-related differences in the ALIE, the length of the spiral canal of cochlea (LSCC), and the volume of components of the inner ear in MD and CRS. Thirty-two with unilateral MD and 14 with CRS were included. Images were acquired with a 3.0-tesla unit using SPACE sequences. The ALIE was measured and the VIE, VC, the volume of the vestibule (VV), and of the semi-circular canals (VSC) were also measured. In CRS, ALIE of the right ear in males was significantly longer than in females. Patients younger than 60 years old with CRS had a significantly larger VIE, VC, and VSC than older than 60. In MD, the ALIE in older than 60 was longer than below 60.

Ocular vestibular evoked myogenic potentials to vertex low frequency vibration as a diagnostic test for superior canal dehiscence.

PubMed

Verrecchia, Luca; Westin, Magnus; Duan, Maoli; Brantberg, Krister

2016-04-01

To explore ocular vestibular evoked myogenic potentials (oVEMP) to low-frequency vertex vibration (125 Hz) as a diagnostic test for superior canal dehiscence (SCD) syndrome. The oVEMP using 125 Hz single cycle bone-conducted vertex vibration were tested in 15 patients with unilateral superior canal dehiscence (SCD) syndrome, 15 healthy controls and in 20 patients with unilateral vestibular loss due to vestibular neuritis. Amplitude, amplitude asymmetry ratio, latency and interaural latency difference were parameters of interest. The oVEMP amplitude was significantly larger in SCD patients when affected sides (53 μVolts) were compared to non-affected (17.2 μVolts) or compared to healthy controls (13.6 μVolts). Amplitude larger than 33.8 μVolts separates effectively the SCD ears from the healthy ones with sensitivity of 87% and specificity of 93%. The other three parameters showed an overlap between affected SCD ears and non-affected as well as between SCD ears and those in the two control groups. oVEMP amplitude distinguishes SCD ears from healthy ones using low-frequency vibration stimuli at vertex. Amplitude analysis of oVEMP evoked by low-frequency vertex bone vibration stimulation is an additional indicator of SCD syndrome and might serve for diagnosing SCD patients with coexistent conductive middle ear problems. Copyright © 2016 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Identification of neonatal hearing impairment: ear-canal measurements of acoustic admittance and reflectance in neonates.

PubMed

Keefe, D H; Folsom, R C; Gorga, M P; Vohr, B R; Bulen, J C; Norton, S J

2000-10-01

1) To describe broad bandwidth measurements of acoustic admittance (Y) and energy reflectance (R) in the ear canals of neonates. 2) To describe a means for evaluating when a YR response is valid. 3) To describe the relations between these YR measurements and age, gender, left/right ear, and selected risk factors. YR responses were obtained at four test sites in well babies without risk indicators, well babies with at least one risk indicator, and graduates of neonatal intensive care units. YR responses were measured using a chirp stimulus at moderate levels over a frequency range from 250 to 8000 Hz. The system was calibrated based on measurements in a set of cylindrical tubes. The probe assembly was inserted in the ear canal of the neonate, and customized software was used for data acquisition. YR responses were measured in over 4000 ears, and half of the responses were used in exploratory data analyses. The particular YR variables chosen for analysis were energy reflectance, equivalent volume and acoustic conductance. Based on the view that unduly large negative equivalent volumes at low frequencies were physically impossible, it was concluded that approximately 13% of the YR responses showed evidence of improper probe seal in the ear canal. To test how these outliers influenced the overall pattern of YR responses, analyses were conducted both on the full data set (N = 2081) and the data set excluding outliers (N = 1825). The YR responses averaged over frequency varied with conceptional age (conception to date of test), gender, left/right ear, and selected risk factors; in all cases, significant effects were observed more frequently in the data set excluding outliers. After excluding outliers and controlling for conceptional age effects, the dichotomous risk factors accounting for the greatest variance in the YR responses were, in rank order, cleft lip and palate, aminoglycoside therapy, low birth weight, history of ventilation, and low APGAR scores. In separate analyses, YR responses varied in the first few days after birth. An analysis showed that the use of a YR test criterion to assess the quality of probe seal may help control the false-positive rate in evoked otoacoustic emission testing. This is the first report of wideband YR responses in neonates. Data were acquired in a few seconds, but the responses are highly sensitive to whether the probe is fully sealed in the ear canal. A real-time acoustic test of probe fit is proposed to better address the probe seal problem. The YR responses provide information on middle-ear status that varies over the neonatal age range and that is sensitive to the presence or absence of risk factors, ear, and gender differences. Thus, a YR test may have potential for use in neonatal screening tests for hearing loss.

A general review of the otolaryngologic manifestations of Down Syndrome.

PubMed

Chin, Christopher J; Khami, Maria M; Husein, Murad

2014-06-01

Down Syndrome (DS) is the most common chromosome abnormality in liveborn children. Otolaryngologists frequently encounter these patients in their practice; in one survey, 50% of DS patients had been seen by Otolaryngology at least once. As such, it is essential that the practicing Otolaryngologist is aware of the otologic, rhinologic, and laryngologic manifestations of this complex disease and comfortable in the management and treatment of these unique patients. Our goal was to provide this information in a concise and definitive document. A comprehensive literature review using PubMed was completed. The terms "Otolaryngology", "Head and neck", "Ear, nose, throat", "Down Syndrome", and "Trisomy 21" were searched in various combinations. Applicable articles that discussed the Otolaryngologic manifestations of Down Syndrome were included. In total, fifty articles were included for review. The Down Syndrome child tends to have smaller external ear canals, have higher rates of chronic ear disease, and may present with conductive, sensorineural, or mixed hearing loss. As such, DS patients should receive behaviouralaudiological testing every 6 monthsand annually after the age of three in addition to closer follow-up by an Otolaryngologist if tympanic membranes cannot be visualized or if the external auditory canals are significantly stenosed. Management should involve close follow-up and a low threshold for PE tube placement to reduce the risks for speech and language delay. Chronic rhinitis in the Down Syndrome patient is common. Retrognathia, hypotonia, and macroglossia can all cause obstructive sleep apnea (OSA) in this population and therefore each DS patient should get an overnight polysomnograph. Subglottic stenosis, vocal cord paralysis and laryngomalacia are not infrequently seen in the Down Syndrome patient. To reduce acquired subglottic stenosis, endotracheal tubes that are at least two sizes smaller than what is appropriate for the patient's age should be used. Down Syndrome is common and there are many Otolaryngologic manifestations. We recommend that this patient population visit an Otolaryngologist on a regular basis and that the practicing Otolaryngologist is comfortable with the management and treatment of the unique challenges faced with these children. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Transcanal microscope-assisted endoscopic myringoplasty in children.

PubMed

Migirov, Lela; Wolf, Michael

2015-04-01

Myringoplasty can be technically difficult in the pediatric patients due to the narrowness of the external auditory canal and the generally small size of the ear. Moreover, temporalis fascia grafts and myringoplasties for anterior perforations are more likely to fail in children. Surgical management of anterior perforations requires total exposure of the anterior angle however a microscope may fail to provide a view of the anterior edge in most of perforations. Recently, different endoscopes are used in the performance of ear surgery in general and myringoplasty in particular. Current study aimed to investigate the outcome of transcanal microscope-assisted endoscopic myringoplasty in homogenous group of children. The medical records of 22 children were retrospectively reviewed for age, perforation size and location, surgical and audiological findings, and outcome. All myringoplasties were performed by first author with a chondro-perichondrial graft that has been harvested from the tragus and placed medial to the tympanic membrane remnants, utilizing the underlay technique and 14-mm length, 3-mm diameter, 0° and 30° endoscopes. A microscope was occasionally used for removal of the sclerotic plaques and releasing adhesions surrounding the ossicles when bimanual manipulations were needed. Surgical success was defined as a tympanic membrane with no perforation, retraction, or graft lateralization for at least 18 months following surgery. Thirteen large-, 8 medium- and 1 small-sized perforations (defined as 75, 50 or 25%, respectively, of the tympanic membrane area), of which 14 were anterior, 2 central and 6 posterior marginal, were repaired. The edges of the defect could not be visualized under a microscope due to bone overhanging or a curved or narrow EAC in 8 anterior perforations. Intact tympanic membranes and dry ears were achieved in all operated children. The audiometric air conduction level (average of 0.5-3 kHz) for the entire cohort ranged between 10-51.3 dB (mean 32.8) preoperatively and between 5-35 dB (mean 18.2) postoperatively. The transcanal microscope-assisted endoscopic myringoplasty had a 100% rate of surgical success in children. This technique can be especially appropriate for patients with narrow external canals, anterior defects and bone overhang making the perforation margins barely visible under a microscope.

The effect of middle ear cavity and superior canal dehiscence on wideband acoustic immittance in fresh human cadaveric specimens

NASA Astrophysics Data System (ADS)

Masud, Salwa F.; Raufer, Stefan; Neely, Stephen T.; Nakajima, Hideko H.

2018-05-01

Superior canal dehiscence (SCD) is a hole in the bony wall of the superior semicircular canal, which can cause various auditory and/or vestibular symptoms and can result in wrong and/or delayed diagnosis. Wideband acoustic immittance (WAI) can potentially distinguish various mechanical middle-ear pathologies as well as inner-ear pathologies non-invasively. We found that in patients, SCD was commonly associated with a narrow-band decrease in power reflectance (PR, derived from WAI) near 1 kHz. Because clinical data has large variation across individual ears and because we do not know the individual "normal" state prior to SCD, we measured WAI in five fresh temporal bone specimens to determine the effects of SCD with respect to the normal state. In temporal bone, we measured PR to assess mechanical changes before and after SCD, as well as to assess the effect of an open or closed middle-ear cavity. After SCD, PR had a consistent decrease between 0.48 and 0.76 kHz, and a slight increase between 1.04 and 1.4 kHz in the open cavity condition. However, in several experiments, we observed low PR around 1 kHz in the normal state before SCD, likely due to the specimen's open middle ear cavity (MEC). Because we see effects of both SCD and open MEC around 1 kHz, some of the SCD effect can be masked by the effect of the MEC in the temporal bone specimens. To compensate for this MEC effect, we estimated the effect of SCD in a closed MEC case, but the effect did not differ significantly from the measured open MEC. This study demonstrates the limitation of temporal bone experiments with open MEC when studying inner-ear lesions with WAI.

CSF otorhinorrhea in a child with inner ear dysplasia: diagnosis with T2-weighted and intrathecal contrast-enhanced MR cisternography.

PubMed

Mehdi, Elnur; Alkan, Alpay; Yetis, Huseyin; Aralasmak, Ayse; Ozdemir, Huseyin

2014-07-01

During the follow-up of recurrent pneumonia in a 9-month-old girl, rhinorrhea with discharge of a positional and intermittent nature was discovered. Radiological assessment was requested to detect any skull base openings and cerebrospinal fluid (CSF) leakage. T2-weighted MR cisternography showed bilateral inner ear dysplasia, communication of the internal auditory canal with the vestibule, and effusion in the right middle ear. Intrathecal contrast-enhanced MR cisternography revealed a CSF fistula from the right internal auditory canal to the Eustachian tube. The patient was operated upon on the right side, and the presence of a CSF leak near the oval window was confirmed. No adverse effects were seen during the short-term and long-term follow-up. Diagnosing this case required special attention, careful examination, and relevant investigations to find the site of CSF leakage in this patient with bilateral inner ear dysplasia.

Silicone impression material foreign body in the middle ear: Two case reports and literature review.

PubMed

Suzuki, Nobuyoshi; Okamura, Koji; Yano, Takuya; Moteki, Hideaki; Kitoh, Ryosuke; Takumi, Yutaka; Usami, Shin-ichi

2015-10-01

We report two cases of impression material foreign body in the middle ear. The first case had been affected with chronic otitis media. The silicone flowed into the middle ear through a tympanic membrane perforation during the process of making an ear mold. About 4 years and 8 months after, the patient had severe vertigo and deafness. We found bone erosion of the prominence of the lateral semicircular canal and diagnosed labyrinthitis caused by silicone impression material. In the second case silicone flowed into the canal wall down mastoid cavity. Both cases required surgery to remove the foreign body. The clinical courses in such cases are variable and timing of surgery is sometimes difficult. In addition to reporting these two cases, we present here a review of the literature regarding impression material foreign bodies. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

[Advances in genetics of congenital malformation of external and middle ear].

PubMed

Wang, Dayong; Wang, Qiuju

2013-05-01

Congenital malformation of external and middle ear is a common disease in ENT department, and the incidence of this disease is second only to cleft lip and palate in the whole congenital malformations of the head and face. The external and middle ear malformations may occur separately, or as an important ear symptom of the systemic syndrome. We systematically review and analysis the genetic research progress of congenital malformation of external and middle ear, which would be helpful to understand the mechanism of external and middle ear development, and to provide clues for the further discovery of new virulence genes.

Inner ear anomalies and conductive hearing loss in children with Apert syndrome: an overlooked otologic aspect.

PubMed

Zhou, Guangwei; Schwartz, Lynn Thomas; Gopen, Quinton

2009-02-01

To identify the occurrence of inner ear structural anomalies and conductive hearing loss (CHL) in children with Apert syndrome. Retrospective review. Pediatric tertiary referral center. Twenty pediatric patients with Apert syndrome were found; all patients (38/40 ears) had inner ear anomalies. Computerized tomography of the head/temporal bone, pure-tone (including air and bone conduction) audiometry, and tympanometry. Imaging demonstrating inner ear anomalies, including malformations of the cochlea, dilated vestibule, and/or semicircular canal; audiologic findings of air-bone gap(s). Hearing loss was found in 90% of the patients with Apert syndrome, and 80% of them had CHL. Air-bone gaps were found at all frequencies, with larger gaps at low frequencies. Fifty percent (20/40) of the ears had better than 0 dB hearing level bone conduction thresholds at 250 and/or 500 Hz. Normal middle ear pressure and mobility were found in all ears with intact eardrum. Inner ear anomalies were found in all patients, and 90% of them had bilateral involvement. Most frequently observed inner ear anomalies were dilated vestibule, malformed lateral semicircular canal, and cochlear dysplasia. Children with Apert syndrome may present with significant CHL that cannot be explained by minor middle ear pathologies alone. This conductive loss may be, at least partially, attributed to the inner ear anomalies; however, these structural anomalies are usually not recognized in these patients. Failure to close air-bone gap after surgical intervention may raise the suspicion of inner ear anomalies, and computed tomographic scan of the temporal bone can provide definitive proof.

Effects of Consecutive Wideband Tympanometry Trials on Energy Absorbance Measures of the Middle Ear

ERIC Educational Resources Information Center

Burdiek, Laina M.; Sun, Xiao-Ming

2014-01-01

Purpose: Wideband acoustic immittance (WAI) is a new technique for assessing middle ear transfer function. It includes energy absorbance (EA) measures and can be acquired with the ear canal pressure varied, known as "wideband tympanometry" (WBTymp). The authors of this study aimed to investigate effects of consecutive WBTymp testing on…

Investigation of the Sound Pressure Level (SPL) of earphones during music listening with the use of physical ear canal models

NASA Astrophysics Data System (ADS)

Aying, K. P.; Otadoy, R. E.; Violanda, R.

2015-06-01

This study investigates on the sound pressure level (SPL) of insert-type earphones that are commonly used for music listening of the general populace. Measurements of SPL from earphones of different respondents were measured by plugging the earphone to a physical ear canal model. Durations of the earphone used for music listening were also gathered through short interviews. Results show that 21% of the respondents exceed the standard loudness/duration relation recommended by the World Health Organization (WHO).

Acoustic Immittance, Absorbance, and Reflectance in the Human Ear Canal

PubMed Central

Rosowski, John J.; Wilber, Laura Ann

2015-01-01

Ear canal measurements of acoustic immittance (a term that groups impedance and its inverse, admittance) and the related quantities of acoustic reflectance and power absorbance have been used to assess auditory function and aid in the differential diagnosis of conductive hearing loss for over 50 years. The change in such quantities after stimulation of the acoustic reflex also has been used in diagnosis. In this article, we define these quantities, describe how they are commonly measured, and discuss appropriate calibration procedures and standards necessary for accurate immittance/reflectance measurements. PMID:27516708

A case discussion on presbyacusis.

PubMed

Angadi, Savita S; Kotrannavar, Vijaykumar S

2013-01-01

Presbyacusis is one among the many socio-medical problems, which is considered as a hidden disability. The hearing impairment in elderly people is described as presbyacusis. Hearing problem among elderly people is a major issue and a person with hearing loss may be unable to hear doorbells and alarms, to respond while talking with anyone, etc. All this can make them feel frustrated, lonely, and depressed. It is the third most common chronic condition after arthritis and hypertensive diseases among elders. Hearing loss can be improved by using the hearing aids. Hearing aids work well for some while for others; it may not be a perfect solution due to many reasons such as some people do not buy aids that meet their needs, incorrect amplification adjustments, low custom design, etc. In classics of Ayurveda this ailment has been described as karnabaadhirya under the heading of ear diseases. Karnapurana (Instillation of medicated oil into the external auditory canal) is one of the major treatments for ear diseases explained in classics. Clinical observation has shown its effectiveness in the management of presbyacusis. A case report of 75-year-old male who presented with complaints of reduced hearing and tinnitus in both ears has been presented here.

A case discussion on presbyacusis

PubMed Central

Angadi, Savita S.; Kotrannavar, Vijaykumar S.

2013-01-01

Presbyacusis is one among the many socio-medical problems, which is considered as a hidden disability. The hearing impairment in elderly people is described as presbyacusis. Hearing problem among elderly people is a major issue and a person with hearing loss may be unable to hear doorbells and alarms, to respond while talking with anyone, etc. All this can make them feel frustrated, lonely, and depressed. It is the third most common chronic condition after arthritis and hypertensive diseases among elders. Hearing loss can be improved by using the hearing aids. Hearing aids work well for some while for others; it may not be a perfect solution due to many reasons such as some people do not buy aids that meet their needs, incorrect amplification adjustments, low custom design, etc. In classics of Ayurveda this ailment has been described as karnabaadhirya under the heading of ear diseases. Karnapurana (Instillation of medicated oil into the external auditory canal) is one of the major treatments for ear diseases explained in classics. Clinical observation has shown its effectiveness in the management of presbyacusis. A case report of 75-year-old male who presented with complaints of reduced hearing and tinnitus in both ears has been presented here. PMID:23741163

Hearing rehabilitation with single-stage bilateral vibroplasty in a child with Franceschetti syndrome.

PubMed

Sargsyan, Sona; Rahne, Torsten; Kösling, Sabrina; Eichler, Gerburg; Plontke, Stefan K

2014-05-01

Hearing is of utmost importance for normal speech and social development. Even children who have mild or unilateral permanent hearing loss may experience difficulties with understanding speech, as well as problems with educational and psycho-social development. The increasing advantages of middle-ear implant technologies are opening new perspectives for restoring hearing. Active middle-ear implants can be used in children and adolescents with hearing loss. In addition to the well-documented results for improving speech intelligibility and quality of hearing in sensorineural hearing loss active middle-ear implants are now successfully used in patients with conductive and mixed hearing loss. In this article we present a case of successful, single-stage vibroplasty, on the right side with the fixation of the FMT on the stapes and PORP CLiP vibroplasty on the left side in a 6-year-old girl with bilateral mixed hearing loss and multiple dyslalia associated with Franceschetti syndrome (mandibulofacial dysostosis). CT revealed bilateral middle-ear malformations as well as an atretic right and stenotic left external auditory canal. Due to craniofacial dysmorphia airway and (post)operative, management is significantly more difficult in patients with a Franceschetti syndrome which in this case favoured a single-stage bilateral procedure. No intra- or postoperative surgical complications were reported. The middle-ear implants were activated 4 weeks after surgery. In the audiological examination 6 months after surgery, the child showed 100% speech intelligibility with activated implants on each side.

Using the Real-Ear-to-Coupler Difference within the American Academy of Audiology Pediatric Amplification Guideline: Protocols for Applying and Predicting Earmold RECDs.

PubMed

Moodie, Sheila; Pietrobon, Jonathan; Rall, Eileen; Lindley, George; Eiten, Leisha; Gordey, Dave; Davidson, Lisa; Moodie, K Shane; Bagatto, Marlene; Haluschak, Meredith Magathan; Folkeard, Paula; Scollie, Susan

2016-03-01

Real-ear-to-coupler difference (RECD) measurements are used for the purposes of estimating degree and configuration of hearing loss (in dB SPL ear canal) and predicting hearing aid output from coupler-based measures. Accurate measurements of hearing threshold, derivation of hearing aid fitting targets, and predictions of hearing aid output in the ear canal assume consistent matching of RECD coupling procedure (i.e., foam tip or earmold) with that used during assessment and in verification of the hearing aid fitting. When there is a mismatch between these coupling procedures, errors are introduced. The goal of this study was to quantify the systematic difference in measured RECD values obtained when using a foam tip versus an earmold with various tube lengths. Assuming that systematic errors exist, the second goal was to investigate the use of a foam tip to earmold correction for the purposes of improving fitting accuracy when mismatched RECD coupling conditions occur (e.g., foam tip at assessment, earmold at verification). Eighteen adults and 17 children (age range: 3-127 mo) participated in this study. Data were obtained using simulated ears of various volumes and earmold tubing lengths and from patients using their own earmolds. Derived RECD values based on simulated ear measurements were compared with RECD values obtained for adult and pediatric ears for foam tip and earmold coupling. Results indicate that differences between foam tip and earmold RECDs are consistent across test ears for adults and children which support the development of a correction between foam tip and earmold couplings for RECDs that can be applied across individuals. The foam tip to earmold correction values developed in this study can be used to provide improved estimations of earmold RECDs. This may support better accuracy in acoustic transforms related to transforming thresholds and/or hearing aid coupler responses to ear canal sound pressure level for the purposes of fitting behind-the-ear hearing aids. American Academy of Audiology.

Numerical analysis of ossicular chain lesion of human ear

NASA Astrophysics Data System (ADS)

Liu, Yingxi; Li, Sheng; Sun, Xiuzhen

2009-04-01

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.

Damage and Recovery of Hair Cells in Fish Canal (But Not Superficial) Neuromasts after Gentamicin Exposure

NASA Technical Reports Server (NTRS)

Song, Jiakun; Yan, Hong Young; Popper, Arthur N.

1995-01-01

Recent evidence demonstrating the presence of two types of sensory hair cells in the ear of a telcost fish (Astronotus ocellatus, the oscar) indicates that hair cell heterogeneity may exist not only in amniotic vertebrates but also in anamniotes. Here we report that a similar heterogeneity between hair cell types may also occur in the other mechanosensory organ of the oscar, the lateral line. We exposed oscars to the aminoglycoside (ototoxic) antibiotic gentamicin sulfate and found damaged sensory hair cells in one class of the lateral line receptors, the canal neuromasts, but not in the other class, the superficial neuromasts. This effect was not due to the canal environment. Moreover, new ciliary bundles on hair cells of the canal neuromasts were found after, and during, gentamicin exposure. The pattern of hair cell destruction and recovery in canal neuromasts is similar to that of type 1-like hair cells found in the striolar region of the utricle and lagena of the oscar after gentamicin treatment. These results suggest that the hair cells in the canal and superficial neuromasts may be similar to type 1-like and type 2 hair cells, respectively, in the fish ear.

Malassezia pachydermatis and M nana predominate amongst the cutaneous mycobiota of Sphynx cats.

PubMed

Volk, Andrea V; Belyavin, Clare E; Varjonen, Katarina; Cadiergues, Marie-Christine; Stevens, Kim B; Bond, Ross

2010-12-01

Carriage of Malassezia species yeasts in healthy Sphynx cats was compared with that in Devon Rex cats (DRC), Cornish Rex cats (CRC) and domestic shorthair (DSH) cats. Swab samples from the external ear, anus and claw folds, and contact plate samples from the axillae and groins, were incubated on modified Dixon's agar at 32°C for 7 days. Malassezia species were isolated from all 18 Sphynx cats; M pachydermatis accounted for 118/140 isolates. Of 20 isolates of M nana, 16 were recovered from the ear canal. M slooffiae was isolated from the claw fold of one cat and the left groin of another. The high counts of M pachydermatis obtained from the axillae, groins and claw folds of the Sphynx cats exceeded those of healthy DSH, CRC and DRC; axillary populations were comparable to those of seborrhoeic DRC. These data support recent reports of high Malassezia species colonisation in Sphynx cats. Copyright © 2010 ISFM and AAFP. Published by Elsevier Ltd. All rights reserved.

The effect of superior-canal opening on middle-ear input admittance and air-conducted stapes velocity in chinchilla

PubMed Central

Songer, Jocelyn E.; Rosowski, John J.

2009-01-01

The recent discovery of superior semicircular canal (SC) dehiscence syndrome as a clinical entity affecting both the auditory and vestibular systems has led to the investigation of the impact of a SC opening on the mechanics of hearing. It is hypothesized that the hole in the SC acts as a “third window” in the inner ear which shunts sound-induced stapes volume velocity away from the cochlea through the opening in the SC. To test the hypothesis and to understand the third window mechanisms the middle-ear input admittance and sound-induced stapes velocity were measured in chinchilla before and after surgically introducing a SC opening and after patching the opening. The extent to which patching returned the system to the presurgical state is used as a control criterion. In eight chinchilla ears a statistically significant, reversible increase in low-frequency middle-ear input admittance magnitude occurred as a result of opening the SC. In six ears a statistically significant reversible increase in stapes velocity was observed. Both of these changes are consistent with the hole creating a shunt pathway that increases the cochlear input admittance. PMID:16875223

The effect of superior-canal opening on middle-ear input admittance and air-conducted stapes velocity in chinchilla.

PubMed

Songer, Jocelyn E; Rosowski, John J

2006-07-01

The recent discovery of superior semicircular canal (SC) dehiscence syndrome as a clinical entity affecting both the auditory and vestibular systems has led to the investigation of the impact of a SC opening on the mechanics of hearing. It is hypothesized that the hole in the SC acts as a "third window" in the inner ear which shunts sound-induced stapes volume velocity away from the cochlea through the opening in the SC. To test the hypothesis and to understand the third window mechanisms the middle-ear input admittance and sound-induced stapes velocity were measured in chinchilla before and after surgically introducing a SC opening and after patching the opening. The extent to which patching returned the system to the presurgical state is used as a control criterion. In eight chinchilla ears a statistically significant, reversible increase in low-frequency middle-ear input admittance magnitude occurred as a result of opening the SC. In six ears a statistically significant reversible increase in stapes velocity was observed. Both of these changes are consistent with the hole creating a shunt pathway that increases the cochlear input admittance.

Revisiting gender, race, and ear differences in peripheral auditory function

NASA Astrophysics Data System (ADS)

Boothalingam, Sriram; Klyn, Niall A. M.; Stiepan, Samantha M.; Wilson, Uzma S.; Lee, Jungwha; Siegel, Jonathan H.; Dhar, Sumitrajit

2018-05-01

Various measures of auditory function are reported to be superior in females as compared to males, in African American compared to Caucasian individuals, and in right compared to left ears. We re-examined the influence of these subject variables on hearing thresholds and otoacoustic emissions (OAEs) in a sample of 887 human participants between 10 and 68 years of age. Even though the variables of interest here have been examined before, previous attempts have largely been limited to frequencies up to 8 kHz. We used state-of-the-art signal delivery and recording techniques that compensated for individual differences in ear canal acoustics, allowing us to measure hearing thresholds and OAEs up to 20 kHz. The use of these modern calibration and recording techniques provided the motivation for re-examining these commonly studied variables. While controlling for age, noise exposure history, and general health history, we attempted to isolate the effects of gender, race, and ear (left versus right) on hearing thresholds and OAEs. Our results challenge the notion of a right ear advantage and question the existence of a significant gender and race differences in both hearing thresholds and OAE levels. These results suggest that ear canal anatomy and acoustics should be important considerations when evaluating the influence of gender, race, and ear on peripheral auditory function.

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

PubMed Central

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. PMID:24281353

Effects of the intensity of masking noise on ear canal recorded low-frequency cochlear microphonic waveforms in normal hearing subjects.

PubMed

Zhang, Ming

2014-07-01

Compared to auditory brainstem responses (ABRs), cochlear microphonics (CMs) may be more appropriate to serve as a supplement to the test of otoacoustic emissions (OAEs). Researchers have shown that low-frequency CMs from the apical cochlea are measurable at the tympanic membrane using high-pass masking noise. Our objective is to study the effect of such noise at different intensities on low-frequency CMs recorded at the ear canal, which is not completely known. Six components were involved in this CM measurement including an ear canal electrode (1), a relatively long and low-frequency toneburst (2), and high-pass masking noise at different intensities (3). The rest components include statistical analysis based on multiple human subjects (4), curve modeling based on amplitudes of CM waveforms (CMWs) and noise intensity (5), and a technique based on electrocochleography (ECochG or ECoG) (6). Results show that low-frequency CMWs appeared clearly. The CMW amplitude decreased with an increase in noise level. It decreased first slowly, then faster, and finally slowly again. In conclusion, when masked with high-pass noise, the low-frequency CMs are measurable at the human ear canal. Such noise reduces the low-frequency CM amplitude. The reduction is noise-intensity dependent but not completely linear. The reduction may be caused by the excited basal cochlea which the low-frequency has to travel and pass through. Although not completely clear, six mechanisms related to such reduction are discussed. Copyright © 2014 Elsevier B.V. All rights reserved.

The Age-Related Orientational Changes of Human Semicircular Canals.

PubMed

Lyu, Hui-Ying; Chen, Ke-Guang; Yin, Dong-Ming; Hong, Juan; Yang, Lin; Zhang, Tian-Yu; Dai, Pei-Dong

2016-06-01

Some changes are found in the labyrinth anatomy during postnatal development. Although the spatial orientation of semicircular canals was thought to be stable after birth, we investigated the age-related orientational changes of human semicircular canals during development. We retrospectively studied the computed tomography (CT) images of both ears of 76 subjects ranged from 1 to 70 years old. They were divided into 4 groups: group A (1-6 years), group B (7-12 years), group C (13-18 years), and group D (>18 years). The anatomical landmarks of the inner ear structures were determined from CT images. Their coordinates were imported into MATLAB software for calculating the semicircular canals orientation, angles between semicircular canal planes and the jugular bulb (JB) position. Differences between age groups were analyzed using multivariate statistics. Relationships between variables were analyzed using Pearson analysis. The angle between the anterior semicircular canal plane and the coronal plane, and the angle between the horizontal semicircular canal plane and the coronal plane were smaller in group D than those in group A (P<0.05). The JB position, especially the anteroposterior position of right JB, correlated to the semicircular canals orientation (P<0.05). However, no statistically significant differences in the angles between ipsilateral canal planes among different age groups were found. The semicircular canals had tendencies to tilt anteriorly simultaneously as a whole with age. The JB position correlated to the spatial arrangement of semicircular canals, especially the right JB. Our calculation method helps detect developmental and pathological changes in vestibular anatomy.

The Effect of Superior Semicircular Canal Dehiscence on Intracochlear Sound Pressures

NASA Astrophysics Data System (ADS)

Nakajima, Hideko Heidi; Pisano, Dominic V.; Merchant, Saumil N.; Rosowski, John J.

2011-11-01

Semicircular canal dehiscence (SCD) is a pathological opening in the bony wall of the inner ear that can result in conductive hearing loss. The hearing loss is variable across patients, and the precise mechanism and source of variability is not fully understood. We use intracochlear sound pressure measurements in cadaveric preparations to study the effects of SCD size. Simultaneous measurement of basal intracochlear sound pressures in scala vestibuli (SV) and scala tympani (ST) quantifies the complex differential pressure across the cochlear partition, the stimulus that excites the partition. Sound-induced pressures in SV and ST, as well as stapes velocity and ear-canal pressure are measured simultaneously for various sizes of SCD followed by SCD patching. At low frequencies (<600 Hz) our results show that SCD decreases the pressure in both SV and ST, as well as differential pressure, and these effects become more pronounced as dehiscence size is increased. For frequencies above 1 kHz, the smallest pinpoint dehiscence can have the larger effect on the differential pressure in some ears. These effects due to SCD are reversible by patching the dehiscence.

a Middle-Ear Reverse Transfer Function Computed from Vibration Measurements of Otoacoustic Emissions on the Ear Drum of the Guinea PIG

NASA Astrophysics Data System (ADS)

Dalhoff, Ernst; Turcanu, Diana; Gummer, Anthony W.

2009-02-01

Using distortion products measured as vibration of the umbo and as sound pressure in the ear canal of guinea pigs, we calculated the corresponding reverse transfer function. We compare the measurements with a middle-ear model taken from the literature and adapted to the guinea pig. A reasonable fit could be achieved. We conclude that the reverse transfer function will be useful to aid fitting a middle-ear model to measured transfer functions of human subjects.

Pathogenesis of Middle Ear Cholesteatoma

PubMed Central

Yamamoto-Fukuda, Tomomi; Hishikawa, Yoshitaka; Shibata, Yasuaki; Kobayashi, Toshimitsu; Takahashi, Haruo; Koji, Takehiko

2010-01-01

Middle ear cholesteatoma is characterized by enhanced proliferation of epithelial cells with aberrant morphological characteristics. To investigate the origin of the cholesteatoma cells, we analyzed spontaneously occurring cholesteatomas associated with a new transplantation model in Mongolian gerbils (gerbils). Cholesteatomas were induced in gerbils with a transplanted tympanic membrane by using the external auditory canal (EAC) ligation method. After the pars flaccida of the tympanic membranes were completely removed from male gerbils, corresponding portions of tympanic membranes of female gerbils were transplanted to the area of defect, and then we ligated the EAC (hybrid-model group). As a control group, the EAC of normal male and female gerbils was ligated without myringoplasty. In all ears of each group, the induced cholesteatomas were seen. In situ PCR was then performed to detect the mouse X chromosome-linked phosphoglycerate kinase-1 (pgk-1) gene on the paraffin sections. One pgk-1 spot in the epithelial nuclei was detected in male cholesteatoma, and two pgk-1 spots were detected in female cholesteatoma, respectively. On the other hand, in the hybrid-model group, we detected not only one but also two pgk-1 spots in the epithelial nuclei of cholesteatoma. These results strengthened the evidence that the origin of epithelial cells in cholesteatoma is the tympanic membrane in this model, but not the residential middle ear epithelial cells or the skin of the EAC. PMID:20413684

Pathogenesis of middle ear cholesteatoma: a new model of experimentally induced cholesteatoma in Mongolian gerbils.

PubMed

Yamamoto-Fukuda, Tomomi; Hishikawa, Yoshitaka; Shibata, Yasuaki; Kobayashi, Toshimitsu; Takahashi, Haruo; Koji, Takehiko

2010-06-01

Middle ear cholesteatoma is characterized by enhanced proliferation of epithelial cells with aberrant morphological characteristics. To investigate the origin of the cholesteatoma cells, we analyzed spontaneously occurring cholesteatomas associated with a new transplantation model in Mongolian gerbils (gerbils). Cholesteatomas were induced in gerbils with a transplanted tympanic membrane by using the external auditory canal (EAC) ligation method. After the pars flaccida of the tympanic membranes were completely removed from male gerbils, corresponding portions of tympanic membranes of female gerbils were transplanted to the area of defect, and then we ligated the EAC (hybrid-model group). As a control group, the EAC of normal male and female gerbils was ligated without myringoplasty. In all ears of each group, the induced cholesteatomas were seen. In situ PCR was then performed to detect the mouse X chromosome-linked phosphoglycerate kinase-1 (pgk-1) gene on the paraffin sections. One pgk-1 spot in the epithelial nuclei was detected in male cholesteatoma, and two pgk-1 spots were detected in female cholesteatoma, respectively. On the other hand, in the hybrid-model group, we detected not only one but also two pgk-1 spots in the epithelial nuclei of cholesteatoma. These results strengthened the evidence that the origin of epithelial cells in cholesteatoma is the tympanic membrane in this model, but not the residential middle ear epithelial cells or the skin of the EAC.

Deflation opening pressure of the eustachian tube.

PubMed

Cohen, D

1989-03-01

Measurements derived from tests of the performance of the eustachian tube (ET) under a variety of normal and pathologic conditions are widely diffuse and overlap considerably. In this survey, the deflation opening pressure (DOP) of the ET was tested in 31 patients suffering either from recurrent otitis (these patients had ventilating tubes inserted) or from chronic otitis media. Oxygen was deflated from the external ear canal, through the middle ear to the pharyngeal end of the ET. The DOP was the pressure needed for the passing of the oxygen. This pressure was usually between 100 to 200 mm H2O. No difference was found in the DOP between infants and adults or between discharging ears and dry ones. A second measurement was obtained through measuring the deflation flow pressure (DFP) required for the continuous passage of oxygen through the ET. The DFP was less than the DOP by approximately 20 to 60 mm H2O, and again no difference was noted between age groups or between infected and noninfected ears. It was concluded that DOP and DFP measurements of the ET are similar in a variety of conditions and therefore cannot indicate whether the ET is normally or abnormally functioning. The existence of a linear connection between the health of the ET and its performance is not proven; hence the role of the ET in predicting the likely outcome of tympanoplasty should be assessed within a different context.

[SOX10 mutation is relevant to inner ear malformation in patients with Waardenburg syndrome].

PubMed

Xu, G Y; Hao, Q Q; Zhong, L L; Ren, W; Yan, Y; Liu, R Y; Li, J N; Guo, W W; Zhao, H; Yang, S M

2016-11-07

Objective: To determine the relevance between the SOX 10 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 SOX 10 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 PAX 3, were also screened. Patients were divided into two groups according to SOX 10 mutation.The Fisher accuracy test was used to determine statistical difference of inner ear deformation incidence between the two groups. Results: Among all 36 patients, 12 were found to have inner ear abnormality. Most abnormalities were posterior semicircular canal deformations, some accompanied with cochlear deformation and an enlarged vestibule. Among all patients, 9 patients were SOX 10 heterozygous mutation carriers, among which six showed bilateral inner ear abnormality. Fisher accuracy test results suggested a significant correlation between the SOX 10 mutation and inner ear abnormality in WS patients ( P =0.036). Conclusion: This study found that WS patients with the SOX 10 mutation are more likely to have deformed inner ears when compared to WS patients without the SOX 10 mutation.

The application of direct current electrical stimulation of the ear and cervical spine kinesitherapy in tinnitus treatment.

PubMed

Mielczarek, Marzena; Konopka, Wieslaw; Olszewski, Jurek

2013-02-01

The aim of the study was to evaluate the effectiveness of electrical stimulations of the hearing organ in tinnitus treatment adapting the frequency of stimulation according to tinnitus frequency, to assess the influence of cervical spine kinesitherapy on tinnitus, as well as to evaluate hearing after electrical stimulations alone and together with cervical spine kinesitherapy. The study comprised 80 tinnitus, sensorineural hearing loss patients (119 tinnitus ears) divided into two groups. In group I (n - 58 tinnitus ears) electrical stimulation of the hearing organ was performed, in group II (n - 61 tinnitus ears) electrical stimulation together with cervical spine kinesitherapy. Hydrotransmissive, selective electrical stimulations were conducted using direct, rectangular current. The passive electrode was placed on the forehead, the active--a silver probe--was immersed in the external ear canal in 0.9% saline solution. The treatment involved fifteen applications of electrical stimulations (each lasted for 4 min) administered three or four times a week (whole treatment lasted approximately 30 days). The evaluation of the results considered a case history (change from permanent to temporary tinnitus), questionnaires (the increase/decrease of the total points) and the audiometric evaluation of hearing level. Before the treatment, group I comprised 51 ears (87.93%) with permanent, and 7 ears (12.07%) with temporary tinnitus; group II - 55 ears (90.17%) with permanent and 6 ears (9.83%) with temporary tinnitus. After the treatment, in both groups the number of ears with permanent tinnitus decreased considerably obtaining the pauses or disappearing of tinnitus. Directly after the treatment, group I comprised 25 ears (43.11%) with permanent, and 10 ears (17.24%) with temporary tinnitus, in 23 ears (39.65%) tinnitus disappeared; group II - 33 ears (54.1%) with permanent and 11 ears (18.03%) with temporary tinnitus, in 17 ears (27.87%) tinnitus disappeared. Regarding questionnaires, improvement was observed in group I - in 43.11% of ears, in group II - 32.8%. In both groups audiometric improvement of hearing was recognized. (1) Electrical stimulation of the hearing organ, with the application of current frequencies according to tinnitus frequencies (selective electrical stimulation), was an efficient method in severe tinnitus treatment. (2) Cervical spine kinesitherapy in the treatment of tinnitus, using electrical stimulation, did not have any supporting influence. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Vestibular sensory functional status of cochlear implanted ears versus non-implanted ears in bilateral profound deaf adults.

PubMed

Cozma, Romică Sebastian; Dima-Cozma, Lucia Corina; Rădulescu, Luminiţa Mihaela; Hera, Maria Cristina; Mârţu, Cristian; Olariu, Raluca; Cobzeanu, Bogdan Mihail; Bitere, Oana Roxana; Cobzeanu, Mihail Dan

2018-01-01

Patients with hearing loss who underwent cochlear implantation can present symptomatic or asymptomatic vestibular damages earlier or later after the surgery. The vestibular permanent lesions could be acute, produced by surgical trauma or could be progressive due to local morphological changes made by the presence of the portelectrode in the inner ear (fibrosis related, ossification, basilar membrane distortion, endolymphatic hydrops). Besides histopathological findings in inner ear of cochlear implanted patients, the vestibular permanent damages could be found by assessment of clinical vestibular status. This study reports the sensorial vestibular functional findings for adults in cochlear implanted ears related to the electrode insertion type (cochleostomy or round window approach) and comparing to non-implanted deaf ears. A total of 20 adult patients with 32 cochlear implanted ears (12 patients with binaural cochlear implant and eight with monoaural) were selected for postoperatory vestibular examination by cervical and ocular vestibular myogenic potentials and vestibular caloric tests. The same tests were made for a control group of 22 non-implanted deaf ears. Functional testing results were reported related to the electrode insertion approach. For the cochleostomy group, we found different deficits: in 40% for saccular function, 44% for utricular function, and 12% horizontal canal dysfunction. In round window group, the deficit was present in 14.29% for saccular function, 28.57% for utricular function, and 28.58% for horizontal canal. In 46.88% of implanted ears, the vestibular function was completely preserved on all tested sensors. In conclusion, the vestibular functional status after inner ear surgery presents sensorial damages in 53.12% ears compare with the vestibular dysfunction existing in 50% of deaf non-operated ears. Round window insertion allows for better conservation of the vestibular function.

The measurement of Eustachian tube function in a hyperbaric chamber using an ear canal microphone.

PubMed

Fischer, Hans-Georg; Koch, Andreas; Kähler, Wataru; Pohl, Michael; Pau, Hans-Wilhelm; Zehlicke, Thorsten

2016-03-01

The purpose of this study was to further the understanding of the opening of the Eustachian tube in relation to changes in barometric pressure. An ear canal microphone was used to measure the specific sounds related to tube opening and possible eardrum movements. Five subjects with normal tube function were examined in a hyperbaric chamber (up to 304 kPa). All active and passive equalization events were recorded and correlated with the subjectively perceived pressure regulation in the measured ear. The signals recorded were clear and reproducible. The acoustic analysis distinguished between the different kinds of equalization. Subjective impressions were confirmed by the recorded frequency of acoustic phenomena (clicks). During compression, the sequence of active equalization manoeuvres was in a more regular and steady pattern than during decompression, when the click sounds varied. The study established a simple technical method for analyzing the function of the Eustachian tube and provided new information about barometric pressure regulation of the middle ear.

Dislocation of the incus into the external auditory canal after mountain-biking accident.

PubMed

Saito, T; Kono, Y; Fukuoka, Y; Yamamoto, H; Saito, H

2001-01-01

We report a rare case of incus dislocation to the external auditory canal after a mountain-biking accident. Otoscopy showed ossicular protrusion in the upper part of the left external auditory canal. CT indicated the disappearance of the incus, and an incus-like bone was found in the left external auditory canal. There was another bony and board-like structure in the attic. During the surgery, a square-shaped bony plate (1 x 1 cm) was found in the attic. It was determined that the bony plate had fallen from the tegmen of the attic. The fracture line in the posterosuperior auditory canal extending to the fossa incudis was identified. According to these findings, it was considered that the incus was pushed into the external auditory canal by the impact of skull injury through the fractured posterosuperior auditory canal, which opened widely enough for incus dislocation. Copyright 2001 S. Karger AG, Basel

Identifying the Optimal Water-Occluding Earplugs: A Scientific Simulation Study.

PubMed

Kovoor, Joshua; Al Hussaini, Ali; Backhouse, Steven

2016-12-01

Numerous types of water-occluding earplugs are available as a means of preventing infection in patients with external and middle ear disease. However, little is known about the comparative efficacies of these earplugs with prolonged water exposure. In this study, we assessed the water impermeability of various earplug materials to prolonged water exposure. Nine earplugs were tested: cotton wool mixed with petroleum jelly, cotton wool externally coated with petroleum jelly, Blu-Tack, foam earplugs, silicone putty, silicone earplugs, flanged earplugs, and hard and soft silicone custom-moulds. Precision-engineered cups were filled with 30 mL water and sealed with lids that contained a 10 mm diameter hole to simulate the ear canal. The aperture was occluded with different earplugs, and the cup was inverted. Computer software was used to record the water loss to the nearest 10 milligrams 720 times over a three-hour period. The test was repeated five times for each material. The water permeability onset, rate, and total amount of water loss varied markedly between the materials; cotton wool mixed with petroleum jelly demonstrated the fastest onset of leak and the highest rate of water loss (p < 0.00001), as well as the largest amount of cumulative water loss (p = 0.00213). The soft silicone custom-mould plugs, hard silicone custom-mould plugs, foam plugs, and silicone putty demonstrated no leaks. This study demonstrates a wide range of water permeabilities of commonly used ear-occluding materials during prolonged water exposure. We found that the generally suggested regimen of cotton wool mixed with petroleum jelly may be inefficacious for substantial periods of water exposure.

[History of the ear speculum. Images from the history of otorhinolaryngology, highlighted by instruments from the collection of the German Medical History Museum in Ingolstadt].

PubMed

Feldmann, H

1996-05-01

BACKGROUND. Inspection of or interventions in the external ear canal and the nostrils pose similar technical problems. This is the reason why early instruments devised for otoscopy and rhinoscopy were based on an identical principle. They were shaped like a pair of tongs, comparable to nasal specula of today. A similar type of instrument had been developed earlier by barber surgeons for inspecting narrow wound cavities. TONG-SHAPED SPECULA. The first description and illustration of an aural and nasal speculum was provided by Guy de Chauliac in Montpellier, France in 1363. Sophisticated models were presented by Fabricius Hildanus in Germany in 1646 and J.J. Perret in Paris in 1772, who offered them in his illustrated catalogue of surgical instruments at fixed prices. W. Kramer (1836) in Berlin improved this tong-shaped instrument and devised the ear speculum named after him that was generally favored during the first half of the 19th century. Further variations of this type were presented by Lincke and Schmalz (1846) in Germany. FUNNEL-SHAPED SPECULA. Ignaz Gruber in Vienna in 1838 devised the first tunnel-shaped ear specula made of metal. They had a simple conical shape, were not divided into separate jaws, and could not be spread. Gruber himself did not publish his invention, but he demonstrated his ear specula to W. R. Wilde from Dublin, who had paid a visit to his office in Vienna. Wilde reported on this in 1844, and subsequently systematically refined Gruber's specula. A. v. Tröltsch from Würzburg (Germany) had seen these instruments at Wilde's office and it was Wilde himself and v. Tröltsch who helped this type of ear speculum to gain acceptance on an international scale. A different type of bottle-shaped ear speculum was first used by Schmalz (1846) and Erhard (1859) in Germany, but it was only developed into a commercially available instrument by Josef Gruber in Vienna in 1870. The ear specula most in use today were first presented by A. Hartmann in Berlin in 1881. SUPPLEMENTARY INVENTIONS. An important supplementary invention was the pneumatic ear speculum by E. Siegle in Stuttgart (Germany) in 1864. It permitted not only inspecting the tympanic membrane but also examining its compliance and response to variations in air pressure in the ear canal. The importance of this instrument was recognized at once and has remained undisputed to this day. J. Bruton, an English military surgeon, presented his otoscope in 1862. It was the first device to incorporate interchangeable ear specula, illumination by a perforated mirror, and a magnifying lens into one handy instrument. It is the precursor of the modern diagnostic sets comprised of a battery-handle, various specula, and accessories for otoscopy, rhinoscopy, and ophthalmoscopy which started to come into use in the late twenties of this century. This historical development of the ear specula is described and illustrated in detail.

Congenital malformations of the inner ear and the vestibulocochlear nerve in children with sensorineural hearing loss: evaluation with CT and MRI.

PubMed

Westerhof, J P; Rademaker, J; Weber, B P; Becker, H

2001-01-01

The purpose of this work was to study the diagnostic value of CT and MRI in children with sensorineural hearing loss and to analyze anatomic abnormalities of the inner ear and the vestibulocochlear nerve in this patient group. We evaluated 42 inner ears in 21 children with congenital deafness who had congenital inner ear malformations and who were candidates for cochlear implants. All patients were studied with high resolution MR and helical CT examinations. The MR study included a T2-weighted 3D fast SE sequence. We describe and tabulate the anatomic abnormalities. Special attention was given to abnormalities of the vestibulocochlear nerve. The field of view in the plane according to the length axis of the internal auditory canal (IAC) was 4 cm. Additional continuous parasagittal reformations perpendicular to the length axis of the IAC were studied with a field of view of 3 cm. CT and MRI allowed accurate identification of malformations of the inner ear in children with congenital deafness. We identified 99 malformations, with a majority of patients demonstrating multiple abnormalities. Common imaging findings were Mondini abnormality and Mondini variants (12/42) and fusion of the lateral or superior semicircular canal with the vestibule (12/42). MRI demonstrated in 9 of 21 patients a rudimentary or absent vestibulocochlear nerve in the auditory canal. CT and MRI are important modalities to analyze the inner ear in children who are candidates for cochlear implants. MRI with an extremely small field of view should be used to study possible abnormalities of the vestibulocochlear nerves. This may alter clinical care and allow cochlear implant placement in patients whose electrodiagnostic studies suggest that the implant should not be performed. The detailed analysis of abnormalities of the inner ear might establish prognostic factors.

Carriage of Malassezia spp. yeasts in Cornish Rex, Devon Rex and Domestic short-haired cats: a cross-sectional survey.

PubMed

Bond, R; Stevens, K; Perrins, N; Ahman, S

2008-10-01

Carriage of Malassezia spp. yeasts in healthy Cornish Rex cats (CRC) was compared with that in Devon Rex (DRC) and Domestic short-haired (DSH) cats. Samples obtained from the left external ear canal, anus and claw fold of digit III of the left fore foot by swabbing, and the axilla and groin using contact plates, were incubated for yeasts on modified Dixon's agar at 32 degrees C for 7 days. Malassezia species were isolated from 90% of the DRC, but from only 39% of the CRC and 50% of the DSH cats. M. pachydermatis accounted for 121 of 141 Malassezia spp. isolates. Five CRC were colonized by M. pachydermatis alone, one CRC yielded only M. nana, and one cat yielded only M. slooffiae, whereas five CRC were colonized by both M. pachydermatis and M. nana and another yielded M. pachydermatis, M. slooffiae and M. nana. M. nana was primarily isolated from the ear canal, whereas M. slooffiae was most often isolated from the claw. Both the frequencies of isolation and the population sizes of M. pachydermatis at all sites sampled in the CRC were comparable to those of 10 healthy DSH cats. Populations of M. pachydermatis in the left axilla and left and right groin in the CRC were significantly lower when compared with counts in a group of 21 healthy DRC, a breed with very similar coat characteristics but prone to seborrheic dermatitis caused by M. pachydermatis.

Comparison of forward (ear-canal) and reverse (round-window) sound stimulation of the cochlea.

PubMed

Stieger, Christof; Rosowski, John J; Nakajima, Hideko Heidi

2013-07-01

The cochlea is normally driven with "forward" stimulation, in which sound is introduced to the ear canal. Alternatively, the cochlea can be stimulated at the round window (RW) using an actuator. During RW "reverse" stimulation, the acoustic flow starting at the RW does not necessarily take the same path as during forward stimulation. To understand the differences between forward and reverse stimulation, we measured ear-canal pressure, stapes velocity, RW velocity, and intracochlear pressures in scala vestibuli (SV) and scala tympani (ST) of fresh human temporal bones. During forward stimulation, the cochlear drive (differential pressure across the partition) results from the large difference in magnitude between the pressures of SV and ST, which occurs due to the high compliance of the RW. During reverse stimulation, the relatively high impedance of the middle ear causes the pressures of SV and ST to have similar magnitudes, and the differential pressure results primarily from the difference in phase of the pressures. Furthermore, the sound path differs between forward and reverse stimulation, such that motion through a third window is more significant during reverse stimulation. Additionally, we determined that although stapes velocity is a good estimate of cochlear drive during forward stimulation, it is not a good measure during reverse stimulation. This article is part of a special issue entitled "MEMRO 2012". Copyright © 2012 Elsevier B.V. All rights reserved.

Congenital middle ear abnormalities with absence of the oval window: diagnosis, surgery, and audiometric outcomes.

PubMed

Su, Yu; Yuan, Hu; Song, Yue-shuai; Shen, Wei-dong; Han, Wei-ju; Liu, Jun; Han, Dong-yi; Dai, Pu

2014-08-01

Congenital absence of the oval window (CAOW) is a rare condition in which the stapes footplate fails to develop, resulting in a significant conductive hearing loss in the affected ear. The purpose of this study was to describe the surgical management and outcomes of patients with CAOW undergoing the oval window drill-out (OWD) procedure. A retrospective chart review of patients with CAOW between 1996 and 2011 was performed. Clinical data of patients who underwent OWD were collected. Seventy-nine patients (103 ears) were confirmed using exploratory tympanotomy as having congenital stapes anomalies and CAOW without any anomalies of the tympanic membrane and external auditory canal. Demographic data, CT findings, operative findings, complications, and preoperative/postoperative audiometry data of patients who underwent OWD were collected. The preoperative and postoperative audiologic findings were analyzed in 42 patients (56 ears) with complete data. Hearing restoration surgery was aborted for various reasons in 14 cases. Six patients underwent revision operations for worsening hearing after their first surgery. The average preoperative 4 tone air conduction threshold was 67 dB; the average 6-month postoperative four tone air conduction threshold was 49 dB, and the average postoperative hearing gain was 18 dB. For the 56 ears, the average 4 tone air conduction threshold 6 months after surgery was significantly lower than the preoperative threshold. The oval window drill-out procedure is a viable operation for patients with congenital absence of the oval window, and it is important for surgeons to develop personalized treatment programs to improve patients' hearing with minimal complications.

Modeling sound transmission of human middle ear and its clinical applications using finite element analysis.

PubMed

Chen, Shou-I; Lee, Ming-Hsiao; Yao, Chih-Min; Chen, Peir-Rong; Chou, Yuan-Fang; Liu, Tien-Chen; Song, Yu-Lin; Lee, Chia-Fone

2013-03-01

We have developed a new finite element (FE) model of human right ear, including the accurate geometry of middle ear ossicles, external ear canal, tympanic cavity, and mastoid cavity. The FE model would be suitable to study the dynamic behaviors of pathological middle ear conditions, including changes of stapedial ligament stiffness, tensor tympani ligament (TTL), and tympanic membrane (TM) stiffness and thickness. Increasing stiffness of stapedial ligament has substantial effect on stapes footplate movement, especially at low frequencies, but less effect on umbo movement. Softer TTL will result in increasing umbo and stapes footplate displacement, especially at low frequencies (f<1000Hz). When the TTL was detached, the vibration amplitude of umbo increased by 6dB at 600Hz and two peaks (300 and 600Hz) were found in the vibration amplitude of stapes footplate. Increasing the stiffness of tensor tympani resulted in a slightly decreased umbo amplitude at very low frequencies (f<500Hz) and significantly decreased displacement up to 12dB at middle frequencies (1000Hz1500Hz. As (TM) thickness was increased, the umbo displacement was reduced, especially at very low frequencies (f<600Hz). Otherwise, the stapes displacement was reduced at all frequencies. Copyright © 2013. Published by Elsevier B.V.

40 CFR 211.203 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... stimuli presented to ten different test subjects under anechoic conditions. (c) ANSI S3.19-1974. A... parameters listed in § 211.210-2(c). (f) Claim. An assertion made by a manufacturer regarding the... the ear and ear canal. The compound is subsequently permanently hardened to retain this shape. (h...

40 CFR 211.203 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... stimuli presented to ten different test subjects under anechoic conditions. (c) ANSI S3.19-1974. A... parameters listed in § 211.210-2(c). (f) Claim. An assertion made by a manufacturer regarding the... the ear and ear canal. The compound is subsequently permanently hardened to retain this shape. (h...

Hydrostatic fluid pressure in the vestibular organ of the guinea pig.

PubMed

Park, Jonas J-H; Boeven, Jahn J; Vogel, Stefan; Leonhardt, Steffen; Wit, Hero P; Westhofen, Martin

2012-07-01

Since inner ear hair cells are mechano-electric transducers the control of hydrostatic pressure in the inner ear is crucial. Most studies analyzing dynamics and regulation of inner ear hydrostatic pressure performed pressure measurements in the cochlea. The present study is the first one reporting about absolute hydrostatic pressure values in the labyrinth. Hydrostatic pressure of the endolymphatic system was recorded in all three semicircular canals. Mean pressure values were 4.06 cmH(2)O ± 0.61 in the posterior, 3.36 cmH(2)O ± 0.94 in the anterior and 3.85 cmH(2)O ± 1.38 in the lateral semicircular canal. Overall hydrostatic pressure in the vestibular organ was 3.76 cmH(2)O ± 0.36. Endolymphatic hydrostatic pressure in all three semicircular canals is the same (p = 0.310). With regard to known endolymphatic pressure values in the cochlea from past studies vestibular pressure values are comparable to cochlear values. Until now it is not known whether the reuniens duct and the Bast's valve which are the narrowest passages in the endolymphatic system are open or closed. Present data show that most likely the endolymphatic system is a functionally open entity.

[Analyses of the factors relevant to revision tympanomastoid surgery].

PubMed

Li, Li; Fan, Zhaomin; Han, Yuechen; Xu, Lei; Chen, Dong; Wang, Haibo

2016-05-01

To analyze factors relevant to revisional tympanomastoid surgery for chronic otitis media(COM). The clinical data of 159 patients (159 ears), who exhibited either wet ear or relapsed after the initial operation, and were subjected to revisional tympanomastoid surgery, were retrospectively analyzed in this study. Of those 159 consecutive patients, 85 were males and 74 were females, aged 11-64 years, with a median age of 36 years old. The situations in terms of intra-operative findings, surgical procedures, change dressing post-operation, dry ear time, and the improvement of aural ability during the second operation, were recorded and analyzed. The second surgery found that, of those 159 patients underwent the re-operation, 67 presented with cholesteatoma and 92 had no cholesteatoma. In addition, the inadequate skeletonization and insufficient opening for mastoid cavity accounted for 70.4% (112/159) of all previous operations, the external auditory canal stenosis for 98.7% (157/159), the high facial ridge leading to insufficient drainage for 61.0% (97/159), the lesion in tympanic ostium of Eustachian tube for 34.6% (55/159), the insufficient drainage due to inappropriate post-operating dressing for 5.0% (8/159), the postauricular incision for 30.8% (49/159), and the endaural incision for 69.2% (110/159). As for the re-operation of the canal wall down mastoidectomy, tympanoplasty plus plastic repairing of cavity of concha were performed in 94 cases, the modified Bondy plus plastic repairing of cavity of concha in four cases, the radical mastoidectomy plus plastic repairing of cavity of concha in 59 cases, and the simple cleaning for mastoid cavity in two cases. Since one to two weeks after the revisional operations, the post-operating dressing was performed with aid of microscopy once a week on average. The average dry ear time ranged from 2 to 6 weeks (median=3 weeks). During a period of 6-93 months for the follow-up, all patients presented with dry ears. The epithelialization of the operating cavity was well and the tympanic membranes were integrity. Neither granulation tissue nor cholesteatoma was found to reoccur. Both pure tone hearing thresholds and air-bone gap decreased in 87 cases after the revisional operation, with statistically significant different in comparison to those two parameters before the operation (P<0.05). The primary causes responsible for the wet ear or reoccurrent cholesteatoma after tympanomastoid surgery may be related to the improper operation procedures and selection of incision, the non-standard operation, inexhaustive removal of pathological tissues, as well as the irregular postoperation change dressing, and other factors.

Diagnosis and medical treatment of otitis externa in the dog and cat.

PubMed

Jacobson, L S

2002-12-01

Otitis externa is no longer viewed as an isolated disease of the ear canal, but is a syndrome that is often a reflection of underlying dermatological disease. Causes are classified as predisposing (increase the risk of otitis); primary (directly induce otitis), secondary (contribute to otitis only in an abnormal ear or in conjunction with predisposing factors) and perpetuating (result from inflammation and pathology in ear, prevent resolution of otitis). Common primary causes include foreign bodies, hypersensitivity (particularly atopy and food allergy), keratinisation disorders (most commonly primary idiopathic seborrhoea and hypothyroidism) and earmites, particularly in cats. A systematic diagnostic procedure is required to identify causes and contributing factors. This should include history, clinical examination, otoscopy and cytology in all cases and culture and sensitivity as well as otitis media assessment and biopsy in severe and recurrent cases. Ancillary tests may be required depending on the underlying cause. Treatment consists of identifying and addressing predisposing and primary factors; cleaning the ear canal; topical therapy; systemic therapy where necessary; client education; follow-up; and preventive and maintenance therapy as required.

Squamous cell carcinoma and consequent otitis in a Long-eared Hedgehog (Hemiechinus auritus)--case report.

PubMed

Gál, Janos; Landauer, Krisztina; Palade, Elena Alina; Ivaskevics, Katalin; Rusvai, Miklós; Demeter, Zoltán

2009-03-01

The authors describe a squamous cell carcinoma arising from the ear canal of a Long-eared Hedgehog (Hemiechinus auritus). No metastasis could be identified elsewhere in the animal. Due to the irritation caused by the tumorous proliferation the animal constantly scratched the affected area, which led to secondary bacterial infection of the middle ear accompanied by the stagnation of an increased volume of local secretions. Using routine haematoxylin and eosin and immunohistochemical staining techniques, the tumour was identified as a squamous cell carcinoma. This work constitutes the first description of such a tumour in a Long-eared Hedgehog.

From labyrinthine aplasia to otocyst deformity.

PubMed

Giesemann, Anja Maria; Goetz, Friedrich; Neuburger, Jürgen; Lenarz, Thomas; Lanfermann, Heinrich

2010-02-01

Inner ear malformations (IEMs) are rare and it is unusual to encounter the rarest of them, namely labyrinthine aplasia (LA) and otocyst deformity. They do, however, provide useful pointers as to the early embryonic development of the ear. LA is characterised as a complete absence of inner ear structures. While some common findings do emerge, a clear definition of the otocyst deformity does not exist. It is often confused with the common cavity first described by Edward Cock. Our purpose was to radiologically characterise LA and otocyst deformity. Retrospective analysis of CT and MRI data from four patients with LA or otocyst deformity. Middle and inner ear findings were categorised by two neuroradiologists. The bony carotid canal was found to be absent in all patients. Posterior located cystic structures were found in association with LA and otocyst deformity. In the most severe cases, only soft tissue was present at the medial border of the middle ear cavity. The individuals with otocyst deformity also had hypoplasia of the petrous apex bone. These cases demonstrate gradual changes in the two most severe IEMs. Clarification of terms was necessary and, based on these findings, we propose defining otocyst deformity as a cystic structure in place of the inner ear, with the cochlea, IAC and carotid canal absent. This condition needs to be differentiated from the common cavity described by Edward Cook. A clear definition of inner ear malformations is essential if outcomes following cochlear implantation are to be compared.

Effects of venting on wind noise levels measured at the eardrum.

PubMed

Chung, King

2013-01-01

Wind noise can be a nuisance to hearing aid users. With the advent of sophisticated feedback reduction algorithms, people with higher degrees of hearing loss are fit with larger vents than previously allowed, and more people with lesser degrees of hearing loss are fit with open hearing aids. The purpose of this study was to examine the effects of venting on wind noise levels in the ear canal for hearing aids with omnidirectional and directional microphones. Two behind-the-ear hearing aids were programmed when they were worn on a Knowles Electronics Manikin for Acoustic Research. The hearing aid worn on the right ear was programmed to the omnidirectional microphone mode and the one on the left to the directional microphone mode. The hearing aids were adjusted to linear amplification with flat frequency response in an anechoic chamber. Gains below 10 dB were used to avoid output limiting of wind noise levels at low input levels. Wind noise samples were recorded at the eardrum location in a wind tunnel at wind velocities ranging from a gentle to a strong breeze. The hearing aids were coupled to #13 tubings (i.e., open vent), or conventional skeleton earmolds with no vent, pressure vents, or 3mm vents. Polar and spectral characteristics of wind noise were analyzed off-line using MatLab programs. Wind noise levels in the ear canals were mostly predicted by vent-induced frequency response changes in the conventional earmold conditions for both omnidirectional and directional hearing aids. The open vent condition, however, yielded the lowest levels, which could not be entirely predicted by the frequency response changes of the hearing aids. This indicated that a wind-related vent effect permitted an additional amount of sound reduction in the ear canal, which could not be explained by known vent effects. For the microphone location, form factor, and gain settings tested, open fit hearing aids yielded lower noise levels at the eardrum location than conventional behind-the-ear hearing aids.

The EarLens System: New Sound Transduction Methods

PubMed Central

Perkins, Rodney; Fay, Jonathan P.; Rucker, Paul; Rosen, Micha; Olson, Lisa; Puria, Sunil

2010-01-01

The hypothesis is tested that an open-canal hearing device, with a microphone in the ear canal, can be designed to provide amplification over a wide bandwidth and without acoustic feedback. In the design under consideration, a transducer consisting of a thin silicone platform with an embedded magnet is placed directly on the tympanic membrane. Sound picked up by a microphone in the ear canal, including sound-localization cues thought to be useful for speech perception in noisy environments, is processed and amplified, and then used to drive a coil near the tympanic-membrane transducer. The perception of sound results from the vibration of the transducer in response the electromagnetic field produced by the coil. Sixteen subjects (ranging from normal-hearing to moderately hearing-impaired) wore this transducer for up to a ten-month period, and were monitored for any adverse reactions. Three key functional characteristics were measured: 1) the maximum equivalent pressure output (MEPO) of the transducer; 2) the feedback gain margin (GM), which describes the maximum allowable gain before feedback occurs; and 3) the tympanic-membrane damping effect (DTM), which describes the change in hearing level due to placement of the transducer on the eardrum. Results indicate that the tympanic-membrane transducer remains in place and is well tolerated. The system can produce sufficient output to reach threshold for those with as much as 60 dBHL of hearing impairment for up to 8 kHz in 86% of the study population, and up to 11.2 kHz in 50% of the population. The feedback gain margin is on average 30 dB except at the ear canal resonance frequencies of 3 and 9 kHz, where the average was reduced to 12 dB and 23 dB respectively. The average value of DTM is close to 0 dB everywhere except in the 2–4 kHz range, where it peaks at 8 dB. A new alternative system that uses photonic energy to transmit both the signal and power to a photodiode and micro-actuator on an EarLens platform is also described. PMID:20116419

Depicting the semicircular canals with inner-ear MRI: a comparison of the SPACE and TrueFISP sequences.

PubMed

Kojima, Shinya; Suzuki, Kazufumi; Hirata, Masami; Shinohara, Hiroyuki; Ueno, Eiko

2013-03-01

To assess the ability of magnetic resonance imaging (MRI) to depict the semicircular canals of the inner ear by comparing results from the sampling perfection with application-optimized contrasts by using different flip angle evolutions (SPACE) sequence with those from the true free induction with steady precession (TrueFISP) sequence. A 1.5-T MRI system was used to perform an in vivo study of 10 healthy volunteers and 17 patients. A three-point visual score was employed for assessing the depiction of the semicircular canals and facial and vestibulocochlear nerves and the contrast-to-noise ratio (CNR) was computed for the vestibule and pons on images with the SPACE and TrueFIPS sequences. There were no susceptibility artifact-related filling defects with the SPACE sequence. However, the TrueFISP sequence showed filling defects for at least one semicircular canal on both sides in seven cases for healthy subjects and in 10 cases for patients. The CNR with the SPACE sequence was significantly higher than with the TrueFISP sequence (P < 0.05). There was no statistically significant difference in depicting the facial and the vestibulocochlear nerves (P = 0.32). For the depiction of the semicircular canal, the SPACE sequence is superior to the TrueFISP sequence. Copyright © 2012 Wiley Periodicals, Inc.

Assessment of Masses of the External Ear With Diffusion-Weighted MR Imaging.

PubMed

Razek, Ahmed Abdel Khalek Abdel

2018-02-01

To assess masses of the external ear with diffusion-weighted MR imaging. Retrospective analysis of 43 consecutive patients with soft tissue mass of the external ear. They underwent single shot diffusion-weighted MR imaging of the ear. The apparent diffusion coefficient (ADC) value of the mass of the external ear was calculated. The final diagnosis was performed by biopsy. The ADC value correlated with the biopsy results. The mean ADC value of malignancy (=27) of external ear (0.95 ± 0.19 × 10 mm/s) was significantly lower (p = 0.001) than that of benign (n = 16) lesions (1.49 ± 0.08 × 10 mm/s). The cutoff ADC used for differentiation of malignancy from benign lesions was 1.18 × 10 mm/s with an area under the curve of 0.959, an accuracy of 93%, a sensitivity of 92%, and specificity of 93%. There was a significant difference in the ADC of well and moderately differentiated malignancy versus poorly and undifferentiated squamous cell carcinoma (p = 0.001), and stages I and II versus stages III and IV (p = 0.04) of squamous cell carcinoma. ADC value is a non-invasive promising imaging parameter that can be used for differentiation of malignancy of the external ear from benign lesions, and grading and staging of squamous cell carcinoma of the external ear.

7. VIEW OF BASEMENT, LOOKING NORTH ALONG EAST BASEMENT WALL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. VIEW OF BASEMENT, LOOKING NORTH ALONG EAST BASEMENT WALL TOWARD TURBINES. AT RIGHT IS A WATER-POWERED EAR CORN CRUSHER (manufacturer unknown), WHICH PERFORMED THE INITIAL COARSE GRINDING OF EAR CORN Photographer: Jet T. Lowe, 1985 - Alexander's Grist Mill, Lock 37 on Ohio & Erie Canal, South of Cleveland, Valley View, Cuyahoga County, OH

30 CFR 62.101 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... noise dose. For the purposes of this part, the exchange rate is 5 decibels (5 dB). Hearing protector. Any device or material, capable of being worn on the head or in the ear canal, sold wholly or in part on the basis of its ability to reduce the level of sound entering the ear, and which has a...

[Comparison of four different staining methods for ear cytology of dogs with otitis externa].

PubMed

Bouassiba, C; Osthold, W; Mueller, R S

2013-01-01

Cytological examination is crucial for the diagnosis and classification of canine otitis externa. Staining should reveal micro-organisms as perpetuating factors of otitis externa. The aim of the study was to compare four different staining methods (Diff-Quik®, Diff-Quik® after dipping in acetone, Gram Quick stain® and a commercial rapid stain for otitis externa) for ear cytology of dogs with otitis externa and to investigate the agreement of cytology and culture. In a study evaluating dogs with otitis externa, five ear swabs (one for culture and four for cytology) were taken from the horizontal part of the external auditory canal of 224 affected ears and compared semi-quantitatively. Diff-Quik® with and without prior dipping in acetone as well as the Gram Quick stain® displayed a high degree of agreement in the detection of micro-organisms (cocci p = 0.2366; rods p = 0.4832; yeasts p = 0.1574), while the commercial otitis rapid stain revealed significantly less micro-organisms (p < 0.001 for all comparisons). The results of the first three stains corresponded to the culture results by >  70%; the agreement was lower with the commercial otitis rapid stain. The quickest and easiest method was staining with Diff-Quik®. Diff-Quik® with or without prior dipping in acetone and the Gram Quick stain® had a high agreement in the detection of microorganisms and can thus be considered nearly equivalent for the diagnosis of otitis externa infectiosa. The commercial otitis rapid stain is less reliable. Based on this study Diff-Quik® can be recommended for the routine cytology of ear swabs. Additionally, a culture may be indicated and must be interpreted in the context of the cytology.

Big Stimulus, Little Ears: Safety in Administering Vestibular Evoked Myogenic Potentials (VEMP) in Children

PubMed Central

Thomas, Megan L.A.; Fitzpatrick, Denis; McCreery, Ryan; Janky, Kristen L.

2017-01-01

Background Cervical and ocular Vestibular Evoked Myogenic Potentials (VEMPs) have become common clinical vestibular assessments. However, VEMP testing requires high intensity stimuli, raising concerns regarding safety with children, where sound pressure levels may be higher due to their smaller ear canal volumes. Purpose The purpose of this study was to estimate the range of peak-to-peak equivalent sound pressure levels (peSPLs) in child and adult ears in response to high intensity stimuli (i.e., 100 dB normal hearing level (nHL)) commonly used for VEMP testing and make a determination of whether acoustic stimuli levels with VEMP testing are safe for use in children. Research Design Prospective Experimental. Study Sample Ten children (4–6 years) and ten young adults (24 – 35 years) with normal hearing sensitivity and middle ear function participated in the study. Data Collection and Analysis Probe microphone peSPL measurements of clicks and 500 Hz tonebursts (TBs) were recorded in tubes of small, medium, and large diameter, and in a Brüel & Kjær Ear Simulator Type 4157 to assess for linearity of the stimulus at high levels. The different diameter tubes were used to approximate the range of cross-sectional areas in infant, child, and adult ears, respectively. Equivalent ear canal volume and peSPL measurements were then recorded in child and adult ears. Lower intensity levels were used in the participant’s ears to limit exposure to high intensity sound. The peSPL measurements in participant ears were extrapolated using predictions from linear mixed models to determine if equivalent ear canal volume significantly contributed to overall peSPL and to estimate the mean and 95% confidence intervals of peSPLs in child and adult ears when high intensity stimulus levels (100 dB nHL) are used for VEMP testing without exposing subjects to high-intensity stimuli. Results Measurements from the coupler and tubes suggested: 1) each stimuli was linear, 2) there were no distortions or non-linearities at high levels, and 3) peSPL increased with decreased tube diameter. Measurements in participant ears suggested: 1) peSPL was approximately 3 dB larger in child compared to adult ears, and 2) peSPL was larger in response to clicks compared to 500 Hz TBs. The model predicted the following 95% confidence interval for a 100 dB nHL click: 127–136.5 dB peSPL in adult ears and 128.7–138.2 dB peSPL in child ears. The model predicted the following 95% confidence interval for a 100 dB nHL 500 Hz TB stimulus: 122.2 – 128.2 dB peSPL in adult ears and 124.8–130.8 dB peSPL in child ears. Conclusions Our findings suggest that 1) when completing VEMP testing, the stimulus is approximately 3 dB higher in a child’s ear, 2) a 500 Hz TB is recommended over a click as it has lower peSPL compared to the click, and 3) both duration and intensity should be considered when choosing VEMP stimuli. Calculating the total sound energy exposure for your chosen stimuli is recommended as it accounts for both duration and intensity. When using this calculation for children, consider adding 3 dB to the stimulus level. PMID:28534730

Big Stimulus, Little Ears: Safety in Administering Vestibular-Evoked Myogenic Potentials in Children.

PubMed

Thomas, Megan L A; Fitzpatrick, Denis; McCreery, Ryan; Janky, Kristen L

2017-05-01

Cervical and ocular vestibular-evoked myogenic potentials (VEMPs) have become common clinical vestibular assessments. However, VEMP testing requires high intensity stimuli, raising concerns regarding safety with children, where sound pressure levels may be higher due to their smaller ear canal volumes. The purpose of this study was to estimate the range of peak-to-peak equivalent sound pressure levels (peSPLs) in child and adult ears in response to high intensity stimuli (i.e., 100 dB normal hearing level [nHL]) commonly used for VEMP testing and make a determination of whether acoustic stimuli levels with VEMP testing are safe for use in children. Prospective experimental. Ten children (4-6 years) and ten young adults (24-35 years) with normal hearing sensitivity and middle ear function participated in the study. Probe microphone peSPL measurements of clicks and 500 Hz tonebursts (TBs) were recorded in tubes of small, medium, and large diameter, and in a Brüel & Kjær Ear Simulator Type 4157 to assess for linearity of the stimulus at high levels. The different diameter tubes were used to approximate the range of cross-sectional areas in infant, child, and adult ears, respectively. Equivalent ear canal volume and peSPL measurements were then recorded in child and adult ears. Lower intensity levels were used in the participant's ears to limit exposure to high intensity sound. The peSPL measurements in participant ears were extrapolated using predictions from linear mixed models to determine if equivalent ear canal volume significantly contributed to overall peSPL and to estimate the mean and 95% confidence intervals of peSPLs in child and adult ears when high intensity stimulus levels (100 dB nHL) are used for VEMP testing without exposing subjects to high-intensity stimuli. Measurements from the coupler and tubes suggested: 1) each stimuli was linear, 2) there were no distortions or nonlinearities at high levels, and 3) peSPL increased with decreased tube diameter. Measurements in participant ears suggested: 1) peSPL was approximately 3 dB larger in child compared to adult ears, and 2) peSPL was larger in response to clicks compared to 500 Hz TBs. The model predicted the following 95% confidence interval for a 100 dB nHL click: 127-136.5 dB peSPL in adult ears and 128.7-138.2 dB peSPL in child ears. The model predicted the following 95% confidence interval for a 100 dB nHL 500 Hz TB stimulus: 122.2-128.2 dB peSPL in adult ears and 124.8-130.8 dB peSPL in child ears. Our findings suggest that 1) when completing VEMP testing, the stimulus is approximately 3 dB higher in a child's ear, 2) a 500 Hz TB is recommended over a click as it has lower peSPL compared to the click, and 3) both duration and intensity should be considered when choosing VEMP stimuli. Calculating the total sound energy exposure for your chosen stimuli is recommended as it accounts for both duration and intensity. When using this calculation for children, consider adding 3 dB to the stimulus level. American Academy of Audiology

The fluid mechanics of the inner-ear disorder BPPV

NASA Astrophysics Data System (ADS)

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.

Morphology suggests noseleaf and pinnae cooperate to enhance bat echolocation.

PubMed

Kuc, Roman

2010-11-01

A protruding noseleaf and concave pinna structures suggest that some bats may use these to enhance their echolocation capabilities. This paper considers two possible mechanisms that each exploit the combination of direct and delayed acoustic paths to achieve more complex emission or sensitivity echolocation patterns. The first is an emission mechanism, in which the protruding noseleaf vibrates to emit sound in both the forward and backward directions, and pinna structures reflect the backward emission to enhance the forward beam. The second is a reception mechanism, which has a direct echo path to the ear canal and a delayed path involving pinna structures reflecting onto the noseleaf and then into the ear canal. A model using Davis' Round-eared Bat illustrates that such direct and delayed acoustic paths provide target elevation cues. The model demonstrates the delayed pinna component can increase the on-axis emission strength, narrow the beam width, and sculpt frequency-dependent beam patterns useful for echolocation.

Aural exostoses (surfer's ear) provide vital fossil evidence of an aquatic phase in Man's early evolution.

PubMed

Rhys Evans, P H; Cameron, M

2017-11-01

For over a century, otolaryngologists have recognised the condition of aural exostoses, but their significance and aetiology remains obscure, although they tend to be associated with frequent swimming and cold water immersion of the auditory canal. The fact that this condition is usually bilateral is predictable since both ears are immersed in water. However, why do exostoses only grow in swimmers and why do they grow in the deep bony meatus at two or three constant sites? Furthermore, from an evolutionary point of view, what is or was the purpose and function of these rather incongruous protrusions? In recent decades, paleoanthropological evidence has challenged ideas about early hominid evolution. In 1992 the senior author suggested that aural exostoses were evolved in early hominid Man for protection of the delicate tympanic membrane during swimming and diving by narrowing the ear canal in a similar fashion to other semiaquatic species. We now provide evidence for this theory and propose an aetiological explanation for the formation of exostoses.

Craniofacial abnormalities among patients with Edwards Syndrome

PubMed Central

Rosa, Rafael Fabiano M.; Rosa, Rosana Cardoso M.; Lorenzen, Marina Boff; Zen, Paulo Ricardo G.; Graziadio, Carla; Paskulin, Giorgio Adriano

2013-01-01

OBJECTIVE To determine the frequency and types of craniofacial abnormalities observed in patients with trisomy 18 or Edwards syndrome (ES). METHODS This descriptive and retrospective study of a case series included all patients diagnosed with ES in a Clinical Genetics Service of a reference hospital in Southern Brazil from 1975 to 2008. The results of the karyotypic analysis, along with clinical data, were collected from medical records. RESULTS: The sample consisted of 50 patients, of which 66% were female. The median age at first evaluation was 14 days. Regarding the karyotypes, full trisomy of chromosome 18 was the main alteration (90%). Mosaicism was observed in 10%. The main craniofacial abnormalities were: microretrognathia (76%), abnormalities of the ear helix/dysplastic ears (70%), prominent occiput (52%), posteriorly rotated (46%) and low set ears (44%), and short palpebral fissures/blepharophimosis (46%). Other uncommon - but relevant - abnormalities included: microtia (18%), orofacial clefts (12%), preauricular tags (10%), facial palsy (4%), encephalocele (4%), absence of external auditory canal (2%) and asymmetric face (2%). One patient had an initial suspicion of oculo-auriculo-vertebral spectrum (OAVS) or Goldenhar syndrome. CONCLUSIONS: Despite the literature description of a characteristic clinical presentation for ES, craniofacial alterations may be variable among these patients. The OAVS findings in this sample are noteworthy. The association of ES with OAVS has been reported once in the literature. PMID:24142310

[Keloid scars of the external ear: a non solved problem].

PubMed

Bejarano Serrano, M; Parri Ferrandis, F J; García Smith, N I; Martínez-Herrada, S; Manzanares Quintela, A; Albert Cazalla, A

2014-01-01

The external ear is a location with high risk of keloid scar formation. Its incidence is growing since general use of piercings and performance of plastic surgery of the external ear. The external ear keloid can be a devasting process for adolescent population which is worried about their appearance. Our aim is to attract attention about the risk of keloid scars of the external ear, reviewing our experience. After dismissing radiotherapy, corticoid infiltration and surgical removal are the most used options, with a high recurrence risk. We have reviewed traumatic, surgical and piercing wounds of the external ear, with a subsequent keloid formation treated in our outpatient clinic, collecting data about wound etiology, treatment and results. During the last 10 years we have found 11 keloid scars, 2 of them improved with topical corticosteroid. Treatment has been surgical in 9 cases, 4 of them with skin graft: 5 recovered and 4 recurred; 2 of them were reoperated. 2 of them were treated with intralesional corticosteroid solely, one recovered and the other one had improved. Treatment management of keloid scars is complex and there isn't a procedure with superior results than the others. Risk of complication must be explained within adolescent population.

Pressure generation during neural stimulation with infrared radiation

NASA Astrophysics Data System (ADS)

Xia, N.; Tan, X.; Xu, Y.; Richter, C.-P.

2017-02-01

This study quantifies laser evoked pressure waves in small confined volumes such as a small dish or the cochlea. The pressure was measured with custom fabricated pressure probes in front of the optical fiber. For the pressure measurements during laser stimulation the probes were inserted into scala tympani or vestibuli. At 164 μJ/pulse, the intracochlear pressure was between 96 and 106 dB (re 20 μPa). The pressure was also measured in the ear canal with a sensitive microphone. It was on average 63 dB (re 20 μPa). At radiant energies large enough to evoke an auditory compound action potential, the outer ear canal equivalent pressure was 36-56 dB (re 20 μPa).

Involvement of Ubiquitin-Editing Protein A20 in Modulating Inflammation in Rat Cochlea Associated with Silver Nanoparticle-Induced CD68 Upregulation and TLR4 Activation

NASA Astrophysics Data System (ADS)

Feng, Hao; Pyykkö, Ilmari; Zou, Jing

2016-05-01

Silver nanoparticles (AgNPs) were shown to temporarily impair the biological barriers in the skin of the external ear canal, mucosa of the middle ear, and inner ear, causing partially reversible hearing loss after delivery into the middle ear. The current study aimed to elucidate the molecular mechanism, emphasizing the TLR signaling pathways in association with the potential recruitment of macrophages in the cochlea and the modulation of inflammation by ubiquitin-editing protein A20. Molecules potentially involved in these signaling pathways were thoroughly analysed using immunohistochemistry in the rat cochlea exposed to AgNPs at various concentrations through intratympanic injection. The results showed that 0.4 % AgNPs but not 0.02 % AgNPs upregulated the expressions of CD68, TLR4, MCP1, A20, and RNF11 in the strial basal cells, spiral ligament fibrocytes, and non-sensory supporting cells of Corti's organ. 0.4 % AgNPs had no effect on CD44, TLR2, MCP2, Rac1, myosin light chain, VCAM1, Erk1/2, JNK, p38, IL-1β, TNF-α, TNFR1, TNFR2, IL-10, or TGF-β. This study suggested that AgNPs might confer macrophage-like functions on the strial basal cells and spiral ligament fibrocytes and enhance the immune activities of non-sensory supporting cells of Corti's organ through the upregulation of CD68, which might be involved in TLR4 activation. A20 and RNF11 played roles in maintaining cochlear homeostasis via negative regulation of the expressions of inflammatory cytokines.

3D-printed pediatric endoscopic ear surgery simulator for surgical training.

PubMed

Barber, Samuel R; Kozin, Elliott D; Dedmon, Matthew; Lin, Brian M; Lee, Kyuwon; Sinha, Sumi; Black, Nicole; Remenschneider, Aaron K; Lee, Daniel J

2016-11-01

Surgical simulators are designed to improve operative skills and patient safety. Transcanal Endoscopic Ear Surgery (TEES) is a relatively new surgical approach with a slow learning curve due to one-handed dissection. A reusable and customizable 3-dimensional (3D)-printed endoscopic ear surgery simulator may facilitate the development of surgical skills with high fidelity and low cost. Herein, we aim to design, fabricate, and test a low-cost and reusable 3D-printed TEES simulator. The TEES simulator was designed in computer-aided design (CAD) software using anatomic measurements taken from anthropometric studies. Cross sections from external auditory canal samples were traced as vectors and serially combined into a mesh construct. A modified tympanic cavity with a modular testing platform for simulator tasks was incorporated. Components were fabricated using calcium sulfate hemihydrate powder and multiple colored infiltrants via a commercial inkjet 3D-printing service. All components of a left-sided ear were printed to scale. Six right-handed trainees completed three trials each. Mean trial time (n = 3) ranged from 23.03 to 62.77 s using the dominant hand for all dissection. Statistically significant differences between first and last completion time with the dominant hand (p < 0.05) and average completion time for junior and senior residents (p < 0.05) suggest construct validity. A 3D-printed simulator is feasible for TEES simulation. Otolaryngology training programs with access to a 3D printer may readily fabricate a TEES simulator, resulting in inexpensive yet high-fidelity surgical simulation. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Earpiece with sensors to measure/monitor multiple physiological variables

NASA Technical Reports Server (NTRS)

Cooper, Tommy G. (Inventor); Schulze, Arthur E. (Inventor)

2003-01-01

An apparatus and method for positioning sensors relative to one another and anatomic features in a non-invasive device for measuring and monitoring multiple physiological variables from a single site uses an earpiece incorporating a shielded pulse oximetry sensor (POS) having a miniaturized set of LEDs and photosensors configured for pulse oximetry measurements in the reflectance mode and located in the earpiece so as to position the POS against a rear wall of an ear canal. The earpiece also includes a thermopile of no larger than 7 mm. in diameter located on the earpiece to so as to position the thermopile past a second turn of an external auditory meatus so as to view the tympanic membrane. The thermopile includes a reference temperature sensor attached to its base for ambient temperature compensation.

Human otoacariasis.

PubMed

Somayaji, K S Gangadhara; Rajeshwari, A

2007-09-01

Accidental entry of foreign bodies into the ear canal is very common. Animate foreign bodies constitute upto 14% of cases, majority being the cockroaches. Not many cases of ticks entering into human ears are found in the scientific literature. Even the available reports are from South Africa, Nepal, Malaysia, Chile and Srilanka. This Indian study discusses the occurence, clinical features, the methods adopted in the removal and the complications of tick infestation of human ear. A total of 144 cases of ticks entering the human ears were studied over a period of two years from Jan 2004 to Dec 2005. This report represents one of the largest recorded series of human otoacariasis available in the Indian literature.

Probe-tube microphone measures in hearing-impaired children and adults.

PubMed

Barlow, N L; Auslander, M C; Rines, D; Stelmachowicz, P G

1988-10-01

This study was designed to investigate the reliability of real-ear measurements of sound pressure level (SPL) and to compare these values with two coupler measures of SPL. A commercially available probe tube microphone system was used to measure real ear SPL in both children and adults. Test-retest reliability decreased as a function of frequency for both groups and, in general, was slightly poorer for the children. For both groups, coupler to real ear differences were larger for the 2 cm3 coupler than for the reduced volume coupler; however, no significant differences were observed between groups. In addition, a measure of ear canal volume was not found to be a good predictor of coupler to real ear discrepancies.

MR imaging of the inner ear: comparison of a three-dimensional fast spin-echo sequence with use of a dedicated quadrature-surface coil with a gadolinium-enhanced spoiled gradient-recalled sequence.

PubMed

Naganawa, S; Ito, T; Fukatsu, H; Ishigaki, T; Nakashima, T; Ichinose, N; Kassai, Y; Miyazaki, M

1998-09-01

To prospectively evaluate the sensitivity and specificity of magnetic resonance (MR) imaging in the inner ear with a long echo train, three-dimensional (3D), asymmetric Fourier-transform, fast spin-echo (SE) sequence with use of a dedicated quadrature-surface phased-array coil to detect vestibular schwannoma in the cerebellopontine angle and the internal auditory canal. In 205 patients (410 ears) with ear symptoms, 1.5-T MR imaging was performed with unenhanced 3D asymmetric fast SE and gadolinium-enhanced 3D gradient-recalled (SPGR) sequences with use of a quadrature surface phased-array coil. The 3D asymmetric fast SE images were reviewed by two radiologists, with the gadolinium-enhanced 3D SPGR images used as the standard of reference. Nineteen lesions were detected in the 410 ears (diameter range, 2-30 mm; mean, 10.5 mm +/- 6.4 [standard deviation]; five lesions were smaller than 5 mm). With 3D asymmetric fast SE, sensitivity, specificity, and accuracy, respectively, were 100%, 99.5%, and 99.5% for observer 1 and 100%, 99.7%, and 99.8% for observer 2. The unenhanced 3D asymmetric fast SE sequence with a quadrature-surface phased-array coli allows the reliable detection of vestibular schwannoma in the cerebellopontine angle and internal auditory canal.

Posterior semicircular canal dehiscence: value of VEMP and multidetector CT.

PubMed

Vanspauwen, R; Salembier, L; Van den Hauwe, L; Parizel, P; Wuyts, F L; Van de Heyning, P H

2006-01-01

To illustrate that posterior semicircular canal dehiscence can present similarly to superior semicircular canal dehiscence. The symptomatology initially presented as probable Menière's disease evolving into a mixed conductive hearing loss with a Carhart notch-type perceptive component suggestive of otosclerosis-type stapes fixation. A small hole stapedotomy resulted in a dead ear and a horizontal semicircular canal hypofunction. Recurrent incapacitating vertigo attacks developed. Vestibular evoked myogenic potential (VEMP) testing demonstrated intact vestibulocollic reflexes. Additional evaluation with high resolution multidetector computed tomography (MDCT) of the temporal bone showed a dehiscence of the left posterior semicircular canal. Besides superior semicircular canal dehiscence, posterior semicircular canal dehiscence has to be included in the differential diagnosis of atypical Menière's disease and/or low tone conductive hearing loss. The value of performing MDCT before otosclerosis-type surgery is stressed. VEMP might contribute to establishing the differential diagnosis.

On the differential diagnosis of Ménière's disease using low-frequency acoustic biasing of the 2f1-f2 DPOAE.

PubMed

Brown, Daniel J; Gibson, William P R

2011-12-01

We have cyclically suppressed the 2f1-f2 distortion product otoacoustic emission (DPOAE) with low-frequency tones (17-97 Hz) as a way of differentially diagnosing the endolymphatic hydrops assumed to be associated with Ménière's syndrome. Round-window electrocochleography (ECochG) was performed in subjects with sensorineural hearing loss (SNHL) on the day of DPOAE testing, and from which the amplitude of the summating potential (SP) was measured, to support the diagnosis of Ménière's syndrome based on symptoms. To summarize and compare the cyclic patterns of DPOAE modulation in these groups we have used the simplest model of DPOAE generation and modulation, by assuming that the DPOAEs were generated by a 1st-order Boltzmann nonlinearity so that the magnitude of the 2f1-f2 DPOAE resembled the 3rd derivative of the Boltzmann function. We have also assumed that the modulation of the DPOAEs by the low-frequency tones was simply due to a sinusoidal change in the operating point on the Boltzmann nonlinearity. We have found the cyclic DPOAE modulation to be different in subjects with Ménière's syndrome (n = 16) when compared to the patterns in normal subjects (n = 16) and in other control subjects with non-Ménière's SNHL and/or vestibular disorders (n = 13). The DPOAEs of normal and non-Ménière's ears were suppressed more during negative ear canal pressure than during positive ear canal pressure. By contrast, DPOAE modulation in Ménière's ears with abnormal ECochG was greatest during positive ear canal pressures. This test may provide a tool for diagnosing Ménière's in the early stages, and might be used to investigate the pathological mechanism underlying the hearing symptoms of this syndrome. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

Assessment of the Antimicrobial Activity of Algae Extracts on Bacteria Responsible of External Otitis

PubMed Central

Pane, Gianluca; Cacciola, Gabriele; Giacco, Elisabetta; Mariottini, Gian Luigi; Coppo, Erika

2015-01-01

External otitis is a diffuse inflammation around the external auditory canal and auricle, which is often occurred by microbial infection. This disease is generally treated using antibiotics, but the frequent occurrence of antibiotic resistance requires the development of new antibiotic agents. In this context, unexplored bioactive natural candidates could be a chance for the production of targeted drugs provided with antimicrobial activity. In this paper, microbial pathogens were isolated from patients with external otitis using ear swabs for over one year, and the antimicrobial activity of the two methanol extracts from selected marine (Dunaliella salina) and freshwater (Pseudokirchneriella subcapitata) microalgae was tested on the isolated pathogens. Totally, 114 bacterial and 11 fungal strains were isolated, of which Staphylococcus spp. (28.8%) and Pseudomonas aeruginosa (P. aeruginosa) (24.8%) were the major pathogens. Only three Staphylococcus aureus (S. aureus) strains and 11 coagulase-negative Staphylococci showed resistance to methicillin. The two algal extracts showed interesting antimicrobial properties, which mostly inhibited the growth of isolated S. aureus, P. aeruginosa, Escherichia coli, and Klebsiella spp. with MICs range of 1.4 × 109 to 2.2 × 1010 cells/mL. These results suggest that the two algae have potential as resources for the development of antimicrobial agents. PMID:26492256

Challenges and outcomes of cholesteatoma management in children with Down syndrome.

PubMed

Ghadersohi, Saied; Bhushan, Bharat; Billings, Kathleen R

2018-03-01

The high incidence of chronic otitis media with effusion and Eustachian tube dysfunction in children with Down syndrome (DS) may predispose them to cholesteatoma formation. Establishing the diagnosis, choosing the appropriate operative intervention, and post-operative care can be challenging. To describe management strategies for cholesteatoma diagnosis, surgical treatment, and post-operative management in children with Down syndrome. Retrospective case series of 14 patients (17 total ears) with Down syndrome diagnosed with cholesteatoma over a 9-year period. A total of 14 patients with cholesteatoma (3 with bilateral disease) were analyzed. Thirteen ears (76.5%) had ≥2 tympanostomy tubes insertions prior to cholesteatoma diagnosis, and otorrhea and hearing loss were the most common presenting symptoms. Common pre-operative CT scan findings included mastoid sclerosis and ossicular erosion. The average age at first surgery was 9.8 years, and the average follow-up was 4.3 years. For acquired cholesteatoma, most ears were managed with canal wall up (CWU) approaches, but ultimately 6/15 (40.0%) required canal wall down (CWD) approaches. Postoperatively, 3 (20.0%) ears developed new tympanic membrane retraction pockets, but no recurrent cholesteatoma. Four (26.7%) ears developed recurrent disease, and 3 (20.0%) had residual disease at secondary procedures. Ossiculoplasty was performed in 4 ears. Twelve (70.6%) ears were rehabilitated with hearing aids or FM systems. The diagnosis of cholesteatoma in Down syndrome was associated with otorrhea, hearing loss, and CT scan findings of ossicular erosion and mastoid sclerosis. Most cases were managed with CWU surgical approaches. Hearing aid use was common post-operatively. Copyright © 2018 Elsevier B.V. All rights reserved.

Unclassified congenital deformities of the external ear.

PubMed

Vathulya, Madhubari

2018-01-01

Congenital ear deformities are a common entity. They are found in isolation or as a part of syndrome in patients. They may involve the external, middle or inner ear or in any of these combinations. Three patients of different ages presented with deformities including mirror image duplication of the superior auricle, unclassified deformities of ear lobule (wavy lobule) and deformity of superior auricle with unclassified variety of lateral ear pit. This article highlights that there are further cases of ear deformities that are noticed in the general population who come for cosmetic correction, and hence, there is a need for further modifying the classification of ear deformities.

Comparative Anatomy of the Bony Labyrinth (Inner Ear) of Placental Mammals

PubMed Central

Ekdale, Eric G.

2013-01-01

Background 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. Principal Findings 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. Significance 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. PMID:23805251

The relationship between external auditory canal temperature and onset of estrus and ovulation in beef heifers.

PubMed

Randi, Federico; McDonald, Michael; Duffy, Pat; Kelly, Alan K; Lonergan, Patrick

2018-04-01

The aim of this study was to evaluate the relationship of body temperature fluctuations, as measured by external auditory canal temperature, to the onset of estrus and ovulation. Beef heifers (n = 44, mean age 23.5 ± 0.4 months, mean weight 603.3 ± 5.7 kg) were fitted with a Boviminder ® ear tag 2 weeks before the start of the estrous synchronization protocol to allow acclimatization. The device recorded the temperature, accurate to 0.01° Fahrenheit, every 10 min and transmitted the data via a base station over the internet where it could be accessed remotely. The estrous cycles of all heifers were synchronized using an 8-day progesterone-based synchronization program; on day 0 a PRID was inserted in conjunction with an injection of GnRH, and PGF2α was administered the day before PRID removal. Heifers were checked for signs of estrus at 4-h intervals (i.e., 6 times per day) commencing 24 h after PRID withdrawal. Beginning 12 h after the onset of estrus, the ovaries were ultrasound scanned at 4-h intervals to determine the time of ovulation. Body temperature was recorded every 10 min and averaged to hourly means for the following 4 periods relative to the detected oestrus onset (=Time 0): Period I: -48 h to -7 h, Period II: -6 h to +6 h, Period III +7 h to ovulation, and Period IV: ovulation to 48 h post ovulation. Data were analysed using a Mixed Model ANOVA in SAS in a completely randomized design to observe effects of induced estrus on external auditory canal temperature. The mean (±SD) interval from removal of the PRID to onset of estrus activity was 46.6 ± 14.7 h. The mean duration of estrus was 16.0 ± 5.67 h and the mean interval from estrus onset to ovulation was 27.9 ± 7.68 h. Highest temperatures (100.95 ± 0.03 °F) were observed in Period II around estrus onset, whereas lowest temperatures were observed in the 48 h preceding estrus onset (100.28 ± 0.03 °F; Period I) and around ovulation (100.30 ± 0.2 °F; Period III)(P < .001). Indeed, around the time of estrus onset (Period II) mean temperature was 0.66 °F (P < .001) higher compared with Period I. Diurnal temperature rhythms were similar (P > .10) before (Period I) and after oestrus (Period III). In conclusion, a significant elevation in external auditory canal temperature was associated with estrus in beef heifers and was followed by a decline in temperature leading up to ovulation approximately 28 h later. Future studies are required to assess pregnancy rates following AI based on changes in external auditory canal temperature. Copyright © 2018 Elsevier Inc. All rights reserved.

Factors affecting the prevalence of mange-mite infestations in stray dogs of Yucatán, Mexico.

PubMed

Rodriguez-Vivas, R I; Ortega-Pacheco, A; Rosado-Aguilar, J A; Bolio, G M E

2003-07-10

The aim of the present study was to determine the factors affecting the prevalence of mange-mite infestations in stray dogs of Yucatán, Mexico. The study was carried out in 200 stray dogs of Mérida capital city of Yucatán, Mexico. Four samples (head, thoracic-abdominal area, extremities and ear) were taken from each animal by skin scraping and examined microscopically in 10% KOH solution to detect the presence of mites. Mites were also collected from the external ear canal of dogs using cotton-tipped swabs. The prevalence of different mite species was calculated. A primary screening was performed using 2xK contingency tables of exposure variables. All variables with P< or =0.20 were analyzed by a logistic-binomial regression. The overall prevalence was 34%. Demodex canis (23.0%) was the most frequent mite, followed by Sarcoptes scabei var. canis (7.0%) and Otodectes cynotis (3.5%). The following factors were found: body condition (bad, OR: 5.35, CI 95%: 1.66-17.3; regular, OR: 3.72, CI 95%: 1.39-9.99) and the presence of macroscopic lesions of dermatosis (OR: 42.80, CI 95%: 13.65-134.24).

Could the Use of Acoustic Reflexes Prior to Administering Distortion Product Otoacoustic Emissions (DPOAEs) Affect the Results of DPOAEs?

PubMed

Garrette, Rachel; Jones, Alisha L; Wilson, Martha W

2018-05-15

The purpose of this study is to investigate whether acoustic reflex threshold testing before administration of distortion product otoacoustic emissions can affect the results of the distortion product otoacoustic emissions testing using an automated protocol. Fifteen young adults with normal hearing ranging in age from 19 to 25 years participated in the study. All participants had clear external ear canals and normal Jerger Type A tympanograms and had passed a hearing screening. Testing was performed using the Interacoustics Titan acoustic reflex threshold and distortion product otoacoustic emissions protocol. Participants underwent baseline distortion product otoacoustic emissions. A paired-samples t test was conducted for both the right and left ears to assess within-group differences between baseline distortion product otoacoustic emissions and repeated distortion product otoacoustic emissions measures. No significant differences were found in distortion product otoacoustic emission measures following administration of acoustic reflexes. The use of a protocol when using an automated system that includes both acoustic reflexes and distortion product otoacoustic emissions is important. Overall, presentation of acoustic reflexes prior to measuring distortion product otoacoustic emission did not affect distortion product otoacoustic emission results; therefore, test sequence can be modified as needed.

[Epidemiology of otomycoses at the University Hospital of Yopougon (Abidjan-Ivory Coast)].

PubMed

Adoubryn, K D; N'Gattia, V K; Kouadio-Yapo, G C; Nigué, L; Zika, D K; Ouhon, J

2014-06-01

Otomycosis is a fungal infection, which leads to a damage of the external auditory meatus. The disease is worldwide in distribution but is said to be more common in tropical countries. Though otomycosis presumably occurs frequently in Africa, reports on its incidence and etiology are rare from Côte d'Ivoire. The objective of this study was to evaluate the prevalence of the disease and to identify aetiological agents as well as the risk factors. A cross-sectional study was carried out in the Otorhinolaryngology Department of the University Teaching Hospital of Yopougon from September 2007 to February 2008. For laboratory investigation, specimens were collected by means of a sterile swab. Samples were inoculated on Sabouraud's Dextrose Agar with and without antibiotics and incubated at 30°C for a period of 1 to 2 weeks. Identification was performed by direct microscopic examination on Cotton Blue Mount preparation and slide culture examination was used for differentiation of morphology. Biotyping was performed using Carbohydrate Fermentation tests, Carbohydrate Assimilation Tests (galerie Api 20 CAux TM - Sanofi Pasteur), Germ tube Test, detection of chlamydospore formation on corn meal agar. A total of 110 patients (sex-ratio=1.2) with suspected cases of otomycosis were investigated. Itching, otalgia, and hypoacusis were the symptoms reported by the patients and the apparent signs were debris in the ear, scabs and inflammation of the external auditory meatus. Of these, 88 cases (80%) were confirmed specifically of mycotic etiology on the basis of positive culture with 92 isolates consisting of yeasts (65.2%) and moulds (34.8%). The predominant etiological agents were Aspergillus flavus (28.4%), Candida guilliermondii (19.3%) and Candida parapsilosis (18.2%). The predisposing factors included previous otological pathology (P=0.010), frequent scratching of the external ear canal and use of ear drops (RR=3.47; IC 95%=1.3-9.27). This study revealed the great prevalence of otomycosis in Abidjan, some predisposing factors and the aetiological agents. Management of otomycosis must include mycological examination for diagnosis and information for changing behaviour patterns leading to infection. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Ear Structures of the Naked Mole-Rat, Heterocephalus glaber, and Its Relatives (Rodentia: Bathyergidae)

PubMed Central

Mason, Matthew J.; Cornwall, Hannah L.; Smith, Ewan St. J.

2016-01-01

Although increasingly popular as a laboratory species, very little is known about the peripheral auditory system of the naked mole-rat, Heterocephalus glaber. In this study, middle and inner ears of naked mole-rats of a range of ages were examined using micro-computed tomography and dissection. The ears of five other bathyergid species (Bathyergus suillus, Cryptomys hottentotus, Fukomys micklemi, Georychus capensis and Heliophobius argenteocinereus) were examined for comparative purposes. The middle ears of bathyergids show features commonly found in other members of the Ctenohystrica rodent clade, including a fused malleus and incus, a synovial stapedio-vestibular articulation and the loss of the stapedius muscle. Heterocephalus deviates morphologically from the other bathyergids examined in that it has a more complex mastoid cavity structure, poorly-ossified processes of the malleus and incus, a ‘columelliform’ stapes and fewer cochlear turns. Bathyergids have semicircular canals with unusually wide diameters relative to their radii of curvature. How the lateral semicircular canal reaches the vestibule differs between species. Heterocephalus has much more limited high-frequency hearing than would be predicted from its small ear structures. The spongy bone forming its ossicular processes, the weak incudo-stapedial articulation, the columelliform stapes and (compared to other bathyergids) reduced cochlear coiling are all potentially degenerate features which might reflect a lack of selective pressure on its peripheral auditory system. Substantial intraspecific differences were found in certain middle and inner ear structures, which might also result from relaxed selective pressures. However, such interpretations must be treated with caution in the absence of experimental evidence. PMID:27926945

Acoustic Reflexes in Normal-Hearing Adults, Typically Developing Children, and Children with Suspected Auditory Processing Disorder: Thresholds, Real-Ear Corrections, and the Role of Static Compliance on Estimates.

PubMed

Saxena, Udit; Allan, Chris; Allen, Prudence

2017-06-01

Previous studies have suggested elevated reflex thresholds in children with auditory processing disorders (APDs). However, some aspects of the child's ear such as ear canal volume and static compliance of the middle ear could possibly affect the measurements of reflex thresholds and thus impact its interpretation. Sound levels used to elicit reflexes in a child's ear may be higher than predicted by calibration in a standard 2-cc coupler, and lower static compliance could make visualization of very small changes in impedance at threshold difficult. For this purpose, it is important to evaluate threshold data with consideration of differences between children and adults. A set of studies were conducted. The first compared reflex thresholds obtained using standard clinical procedures in children with suspected APD to that of typically developing children and adults to test the replicability of previous studies. The second study examined the impact of ear canal volume on estimates of reflex thresholds by applying real-ear corrections. Lastly, the relationship between static compliance and reflex threshold estimates was explored. The research is a set of case-control studies with a repeated measures design. The first study included data from 20 normal-hearing adults, 28 typically developing children, and 66 children suspected of having an APD. The second study included 28 normal-hearing adults and 30 typically developing children. In the first study, crossed and uncrossed reflex thresholds were measured in 5-dB step size. Reflex thresholds were analyzed using repeated measures analysis of variance (RM-ANOVA). In the second study, uncrossed reflex thresholds, real-ear correction, ear canal volume, and static compliance were measured. Reflex thresholds were measured using a 1-dB step size. The effect of real-ear correction and static compliance on reflex threshold was examined using RM-ANOVA and Pearson correlation coefficient, respectively. Study 1 replicated previous studies showing elevated reflex thresholds in many children with suspected APD when compared to data from adults using standard clinical procedures, especially in the crossed condition. The thresholds measured in children with suspected APD tended to be higher than those measured in the typically developing children. There were no significant differences between the typically developing children and adults. However, when real-ear calibrated stimulus levels were used, it was found that children's thresholds were elicited at higher levels than in the adults. A significant relationship between reflex thresholds and static compliance was found in the adult data, showing a trend for higher thresholds in ears with lower static compliance, but no such relationship was found in the data from the children. This study suggests that reflex measures in children should be adjusted for real-ear-to-coupler differences before interpretation. The data in children with suspected APD support previous studies suggesting abnormalities in reflex thresholds. The lack of correlation between threshold and static compliance estimates in children as was observed in the adults may suggest a nonmechanical explanation for age and clinically related effects. American Academy of Audiology

Hearing aid silicone impression material as a foreign body in the middle ear.

PubMed

Lee, Hyun-Min; Yi, Keun-Ik; Jung, Jae-Hoon; Lee, Il-Woo

We report an extremely rare case of hearing aid silicone impression material as a foreign body in the middle ear. Symptoms of the patient were otorrhea and vertigo after taking of a mold impression on his only hearing ear, and the symptoms mimicked chronic otitis media. A temporal bone CT scan revealed foreign body material in the middle ear and Eustachian tube. An intact canal wall mastoidectomy with a facial recess approach and type IV tympanoplasty was performed to remove the silicone impression material. In addition to the case report, we review the literature regarding impression material foreign bodies. Copyright © 2016 Elsevier Inc. All rights reserved.

Modeling Analysis of Biomechanical Changes of Middle Ear and Cochlea in Otitis Media

NASA Astrophysics Data System (ADS)

Gan, Rong Z.; Zhang, Xiangming; Guan, Xiying

2011-11-01

A comprehensive finite element (FE) model of the human ear including the ear canal, middle ear, and spiral cochlea was developed using histological sections of human temporal bone. The cochlea was modeled with three chambers separated by the basilar membrane and Reissner's membrane and filled with perilymphatic fluid. The viscoelastic material behavior was applied to middle ear soft tissues based on dynamic measurements of tissues in our lab. The model was validated using the experimental data obtained in human temporal bones and then used to simulate various stages of otitis media (OM) including the changes of morphology, mechanical properties, pressure, and fluid level in the middle ear. Function alterations of the middle ear and cochlea in OM were derived from the model and compared with the measurements from temporal bones. This study indicates that OM can be simulated in the FE model to predict the hearing loss induced by biomechanical changes of the middle ear and cochlea.

The effects of listening environment and earphone style on preferred listening levels of normal hearing adults using an MP3 player.

PubMed

Hodgetts, William E; Rieger, Jana M; Szarko, Ryan A

2007-06-01

The main objective of this study was to determine the influence of listening environment and earphone style on the preferred-listening levels (PLLs) measured in users' ear canals with a commercially-available MP3 player. It was hypothesized that listeners would prefer higher levels with earbud headphones as opposed to over-the-ear headphones, and that the effects would depend on the environment in which the user was listening. A secondary objective was to use the measured PLLs to determine the permissible listening duration to reach 100% daily noise dose. There were two independent variables in this study. The first, headphone style, had three levels: earbud, over-the-ear, and over-the-ear with noise reduction (the same headphones with a noise reduction circuit). The second, environment, also had 3 levels: quiet, street noise and multi-talker babble. The dependent variable was ear canal A-weighted sound pressure level. A 3 x 3 within-subjects repeated-measures ANOVA was used to analyze the data. Thirty-eight normal hearing adults were recruited from the Faculty of Rehabilitation Medicine at the University of Alberta. Each subject listened to the same song and adjusted the level until it "sounded best" to them in each of the 9 conditions. Significant main effects were found for both the headphone style and environment factors. On average, listeners had higher preferred listening levels with the earbud headphones, than with the over-the-ear headphones. When the noise reduction circuit was used with the over-the-ear headphones, the average PLL was even lower. On average, listeners had higher PLLs in street noise than in multi-talker babble and both of these were higher than the PLL for the quiet condition. The interaction between headphone style and environment was also significant. Details of individual contrasts are explored. Overall, PLLs were quite conservative, which would theoretically allow for extended permissible listening durations. Finally, we investigated the maximum output level of the MP3 player in the ear canals of authors 1 and 3 of this paper. Levels were highest with the earbud style, followed by the over-the-ear with noise reduction. The over-the-ear headphone without noise reduction had the lowest maximum output. The majority of MP3 players are sold with the earbud style of headphones. Preferred listening levels are higher with this style of headphone compared to the over-the-ear style. Moreover, as the noise level in the environment increases, earbud users are even more susceptible to background noise and consequently increase the level of the music to overcome this. The result is an increased sound pressure level at the eardrum. However, the levels chosen by our subjects suggest that MP3 listening levels may not be as significant a concern as has been reported recently in the mainstream media.

A metastatic glomus jugulare tumor. A temporal bone report

DOE Office of Scientific and Technical Information (OSTI.GOV)

El Fiky, F.M.; Paparella, M.M.

The clinicopathologic findings in the temporal bone of a patient with a highly malignant metastasizing glomus jugulare tumor are reported. The patient exhibited all the symptoms of primary malignant tumors of the ear, including facial paralysis, otorrhea, pain, hearing loss, tinnitus, dizziness, and vertigo. He was treated with cobalt irradiation followed by radium implant in the ear canal for a residual tumor; then a left-sided radical mastoidectomy was performed.

Pressurized transient otoacoustic emissions measured using click and chirp stimuli.

PubMed

Keefe, Douglas H; Patrick Feeney, M; Hunter, Lisa L; Fitzpatrick, Denis F; Sanford, Chris A

2018-01-01

Transient-evoked otoacoustic emission (TEOAE) responses were measured in normal-hearing adult ears over frequencies from 0.7 to 8 kHz, and analyzed with reflectance/admittance data to measure absorbed sound power and the tympanometric peak pressure (TPP). The mean TPP was close to ambient. TEOAEs were measured in the ear canal at ambient pressure, TPP, and fixed air pressures from 150 to -200 daPa. Both click and chirp stimuli were used to elicit TEOAEs, in which the incident sound pressure level was constant across frequency. TEOAE levels were similar at ambient and TPP, and for frequencies from 0.7 to 2.8 kHz decreased with increasing positive and negative pressures. At 4-8 kHz, TEOAE levels were larger at positive pressures. This asymmetry is possibly related to changes in mechanical transmission through the ossicular chain. The mean TEOAE group delay did not change with pressure, although small changes were observed in the mean instantaneous frequency and group spread. Chirp TEOAEs measured in an adult ear with Eustachian tube dysfunction and TPP of -165 daPa were more robust at TPP than at ambient. Overall, results demonstrate the feasibility and clinical potential of measuring TEOAEs at fixed pressures in the ear canal, which provide additional information relative to TEOAEs measured at ambient pressure.

Cochlear Implantation in Patients With CHARGE Syndrome.

PubMed

Rah, Yoon Chan; Lee, Ji Young; Suh, Myung-Whan; Park, Moo Kyun; Lee, Jun Ho; Chang, Sun O; Oh, Seung-Ha

2016-11-01

To determine the optimal surgical approach for cochlear implantation (CI) preoperatively based on the spatial relation of a displaced facial nerve (FN) and middle ear structures and to analyze clinical outcomes of CHARGE syndrome. Facial nerve displacement and associated deviation of inner ear structures were analyzed in 13 patients (17 ears) with CHARGE syndrome who underwent CI. Surgical accessibility through the facial recess was assessed based on anatomical landmarks. Postoperative speech performance and associated clinical characteristics were analyzed. The most consistently identified ear anomalies were semicircular canal aplasia (100%), ossicular anomaly (100%), and vestibular hypoplasia (88%). Facial nerve displacement was found in 77% of cases (anteroinferior: 47%, anterior: 24%, inferior: 6%). The width of available surgical space around facial recess was significantly greater in cases of facial recess approach (2.85 ± 0.9 mm) than those of alternative approach (0.12 ± 0.29 mm, P = .02). Postoperatively, 53% achieved better than category 4 on the categories of auditory perception (CAP) scale. The CAP category was significantly correlated with internal auditory canal diameter (P = .025) and did not differ according to the applied surgical approach. Preoperative determination of surgical accessibility through facial recess would be useful for safe surgical approach, and successful hearing rehabilitation was achievable by applying appropriate surgical approaches. © The Author(s) 2016.

Bilateral presence of two root canals in maxillary central incisors: A rare case study.

PubMed

Kavitha, M; Gokul, Kannan; Ramaprabha, B; Lakshmi, Amudha

2014-04-01

Success in root canal treatment is achieved after thorough cleaning and shaping followed by complete obturation of the canal system. Therefore, endodontic therapy requires specific and complete knowledge of the internal and external dental anatomy, and its variations in presentation. The internal anatomy of the maxillary central incisor is well-known and usually presents one root canal system. This case report describes an endodontic treatment of traumatized both maxillary central incisors with two canal systems. Knowledge of dental anatomy is fundamental for proper endodontic practice. When root canal treatment is performed, the clinician should be aware that both external and internal anatomy may be abnormal.

Fibrin tissue adhesive and autologous concha cartilage for reconstruction of the posterior-superior canal wall of the chinchilla middle ear.

PubMed

Siedentop, Karl H; O'Grady, Kevin; Bhattacharyya, Tapan K; Shah, Ami

2004-05-01

We conducted this study to prove that fibrin tissue adhesive (FTA) is safe, efficacious, biocompatible, and readily biodegradable with no deleterious side effects for fixation of a cartilage graft to bone along the chinchilla canal wall. A posterior-superior canal defect was created in 12 chinchillas. The canal walls of six chinchillas were closed with autologous concha cartilage alone, whereas the canal wall of the remaining six animals were closed with cartilage in conjunction with fibrin tissue adhesive. Animals were killed 8 weeks postoperatively. Three of six cartilage grafts were displaced in the graft alone group, whereas all six grafts in the cartilage with FTA group healed without displacement. Fibrin tissue adhesive was found to be effective, biocompatible, biodegradable, and without any deleterious side effects for reconstruction of the superior-posterior canal wall of chinchillas.

External auditory canal stenosis due to the use of powdered boric acid.

PubMed

Dündar, Riza; Soy, Fatih Kemal; Kulduk, Erkan; Muluk, Nuray Bayar; Cingi, Cemal

2014-09-01

Acquired stenosis of the external auditory canal (EAC) may occur because of chronic external otitis, recurrent chronic catarrhal otitis media associated with tympanic membrane perforation, chronic dermatitis, tumors, and trauma. Stenosis occurs generally at the one-third bone part of the external auditory canal. In this article, we present 3 cases of acquired EAC stenosis due to the previous powdered boric acid application. Besides the presentation of surgical intervetions in these cases, we want to notify the physicians not to use or carefully use powdered boric acid because of the complication of EAC stenosis.

Types of Hearing Aids

MedlinePlus

... hearing impairment. Most hearing aids share several similar electronic components, including a microphone that picks up sound; ... the ear canal; and batteries that power the electronic parts. Hearing aids differ by: design technology used ...

Posture systematically alters ear-canal reflectance and DPOAE properties

PubMed Central

Voss, Susan E.; Adegoke, Modupe F.; Horton, Nicholas J.; Sheth, Kevin N.; Rosand, Jonathan; Shera, Christopher A.

2010-01-01

Several studies have demonstrated that the auditory system is sensitive to changes in posture, presumably through changes in intracranial pressure (ICP) that in turn alter the intracochlear pressure, which affects the stiffness of the middle-ear system. This observation has led to efforts to develop an ear-canal based noninvasive diagnostic measure for monitoring ICP, which is currently monitored invasively via access through the skull or spine. Here, we demonstrate the effects of postural changes, and presumably ICP changes, on distortion product otoacoustic emissions (DPOAE) magnitude, DPOAE angle, and power reflectance. Measurements were made on 12 normal-hearing subjects in two postural positions: upright at 90 degrees and tilted at −45 degrees to the horizontal. Measurements on each subject were repeated five times across five separate measurement sessions. All three measures showed significant changes (p < 0.001) between upright and tilted for frequencies between 500 and 2000 Hz, and DPOAE angle changes were significant at all measured frequencies (500–4000 Hz). Intrasubject variability, assessed via standard deviations for each subject’s multiple measurements, were generally smaller in the upright position relative to the tilted position. PMID:20227475

Long-term outcomes of a transmastoid lateral semicircular canal approach to congenital CSF otorrhea in children associated with recurrent meningitis and severe inner ear malformation.

PubMed

Wang, Jie; Li, Yongxin; Chen, Shubin; Hao, Xinping

2016-08-01

To investigate the long-term effectiveness of transmastoid lateral semicircular canal approach (TMLSCCA) to repair cerebrospinal fluid (CSF) leakage in children associated with recurrent meningitis and severe congenital inner malformation. A retrospective study was conducted in a university hospital, academic medical center. Fifteen children with recurrent meningitis, secondary to severe congenital inner ear malformation, were included in the study. All of them had CSF associated otorrhea and treated using TLSCCA to repair CSF otorrhea by packing the vestibule with muscle and fascia. Observation of the status of postoperative CSF leakage, recurrence of meningitis and complication were conducted. None of the cases had recurrent meningitis and CSF leakage after their TLSCCA procedure in the follow-up period of 1-8.5 years. One case presented with transient facial nerve paralysis and completely recovered 3 months later. TLSCCA for CSF otorrhea in children with recurrent meningitis secondary to congenital inner ear malformation is an alternative approach that offers some advantages. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Requirement for Lmo4 in the Vestibular Morphogenesis of Mouse Inner Ear

PubMed Central

Deng, Min; Pan, Ling; Xie, Xiaoling; Gan, Lin

2009-01-01

During development, compartmentalization of an early embryonic structure produces blocks of cells with distinct properties and developmental potentials. The auditory and vestibular components of vertebrate inner ears are derived from defined compartments within the otocyst during embryogenesis. The vestibular apparatus, including three semicircular canals, saccule, utricle, and their associated sensory organs, detects angular and linear acceleration of the head and relays the information through vestibular neurons to vestibular nuclei in the brainstem. How the early developmental events manifest vestibular structures at the molecular level is largely unknown. Here, we show that LMO4, a LIM-domain-only transcriptional regulator, is required for the formation of semicircular canals and their associated sensory cristae. Targeted disruption of Lmo4 resulted in the dysmorphogenesis of the vestibule and in the absence of three semicircular canals, anterior and posterior cristae. In Lmo4-null otocysts, canal outpouches failed to form and cell proliferation was reduced in the dorsolateral region. Expression analysis of the known otic markers showed that Lmo4 is essential for the normal expression of Bmp4, Fgf10, Msx1, Isl1, Gata3, and Dlx5 in the dorsolateral domain of the otocyst, whereas the initial compartmentalization of the otocyst remains unaffected. Our results demonstrate that Lmo4 controls the development of the dorsolateral otocyst into semicircular canals and cristae through two distinct mechanisms: regulating the expression of otic specific genes and stimulating the proliferation of the dorsolateral part of the otocyst. PMID:19913004

[The role of acoustic impedance test in the diagnosis for occupational noise induced deafness].

PubMed

Chen, H; Xue, L J; Yang, A C; Liang, X Y; Chen, Z Q; Zheng, Q L

2018-01-20

Objective: To investigate the characteristics of acoustic impedance test and its diagnostic role for occupational noise induced deafness, in order to provide an objective basis for the differential diagnosis of occupational noise induced deafness. Methods: A retrospective study was conducted to investigate the cases on the diagnosis of occupational noise-induced deafness in Guangdong province hospital for occupational disease prevention and treatment from January 2016 to January 2017. A total of 198 cases (396 ears) were divided into occupation disease group and non occupation disease group based on the diagnostic criteria of occupational noise deafness in 2014 edition, acoustic conductivity test results of two groups were compared including tympanograms types, external auditory canal volume, tympanic pressure, static compliance and slope. Results: In the occupational disease group, 204 ears were found to have 187 ears (91.67%) of type A, which were significantly higher than those in the non occupational disease group 143/192 (74.48%) , the difference was statistically significant (χ(2)=21.038, P <0.01). Detection of Ad or As type, occupation disease group in other type were 16/204 (7.84%) , 3/204 (1.47%) , were lower than Ad or As type of occupation disease group (15.63%) , other type (9.38%) , the differences were statistically significant[ (χ(2)=5.834, P <0.05) , (χ(2)=12.306, P <0.01) ]. Occupation disease group canal volume average (1.68±0.39) ml higher than that of non occupation disease group (1.57 ± 0.47) ml, the difference was statistically significant ( t =2.756, P <0.01) ; occupation disease group mean static compliance (1.06±0.82) ml higher than that of non occupation disease group (0.89±0.64) ml. The difference was statistically singificant ( t =2.59, P <0.01) . Conclusion: We observed that acoustic impedance test had obvious auxiliary function in the differential diagnosis of occupational noise induced deafness, More than 90% of the confirmed cases showed an A-form tympanograms, it is one of the objective examination methods which can be used in the differential diagnosis of pseudo deafness.

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

PubMed

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.

Clinical use of vestibular evoked myogenic potentials in the evaluation of patients with air-bone gaps.

PubMed

Zhou, Guangwei; Poe, Dennis; Gopen, Quinton

2012-10-01

To determine the value of vestibular evoked myogenic potential (VEMP) test in clinical evaluation of air-bone gaps. Retrospective case review. Tertiary referral center. A total of 120 patients underwent VEMP testing during clinical investigation of significant air-bone gaps in their audiograms. Otologic examination and surgeries, high-resolution computerized tomography (CT), air and bone audiometry, tympanometry, acoustic reflex, and VEMP test. Imaging studies demonstrating structural anomalies in the temporal bone. Audiologic outcomes of air-bone gaps and VEMP thresholds. Surgical findings confirming imaging results. Middle ear pathologies, such as otosclerosis and chronic otitis media, were identified in 50 patients, and all of them had absent VEMP responses elicited by air-conduction stimuli. Moreover, 13 of them had successful middle ear surgeries with closures of the air-bone gaps. Abnormally low VEMP thresholds were found in 71 of 73 ears with inner ear anomalies, such as semicircular canal dehiscence and enlarged vestibular aqueduct. Seven patients with superior semicircular canal dehiscence underwent plugging procedure via middle fossa approach, and VEMP thresholds became normalized after the surgery in 3 of them. VEMP test failed to provide accurate diagnosis in only 3 cases. Air-bone gaps may be a result of various otologic pathologies, and the VEMP test is useful during clinical evaluation, better than tympanometry and acoustic reflexes. To avoid unnecessary middle ear surgery for air-bone gaps with unknown or unsure cause, VEMP test should be used in the differential diagnosis before an expensive imaging study.

Conductive Hearing Loss Caused by Third-Window Lesions of the Inner Ear

PubMed Central

Merchant, Saumil N.; Rosowski, John J.

2008-01-01

Background Various authors have described conductive hearing loss (CHL), defined as an air-bone gap on audiometry, in patients without obvious middle ear pathologic findings. Recent investigations have suggested that many of these cases are due to disorders of the inner ear, resulting in pathologic third windows. Objective To provide an overview of lesions of the inner ear resulting in a CHL due to a third-window mechanism. The mechanism of the CHL is explained along with a classification scheme for these disorders. We also discuss methods for diagnosis of these disorders. Data Sources The data were compiled from a review of the literature and recent published research on middle and inner ear mechanics from our laboratory. Conclusion A number of disparate disorders affecting the labyrinth can produce CHL by acting as a pathologic third window in the inner ear. The common denominator is that these conditions result in a mobile window on the scala vestibuli side of the cochlear partition. The CHL results by the dual mechanism of worsening of air conduction thresholds and improvement of bone conduction thresholds. Such lesions may be anatomically discrete or diffuse. Anatomically discrete lesions may be classified by location: semicircular canals (superior, lateral, or posterior canal dehiscence), bony vestibule (large vestibular aqueduct syndrome, other inner ear malformations), or the cochlea (carotid-cochlear dehiscence, X-linked deafness with stapes gusher, etc.). An example of an anatomically diffuse lesion is Paget disease, which may behave as a distributed or diffuse third window. Third-window lesions should be considered in the differential diagnosis of CHL in patients with an intact tympanic membrane and an aerated, otherwise healthy, middle ear. Clues to suspect such a lesion include a low-frequency air-bone gap with supranormal thresholds for bone conduction, and presence of acoustic reflexes, vestibular evoked myogenic responses, or otoacoustic emission responses despite the CHL. Imaging studies can help confirm the diagnosis. PMID:18223508

Wideband reflectance in Down syndrome.

PubMed

Soares, Jordana Costa; Urosas, Juliana Granja; Calarga, Karenina Santos; Pichelli, Tathiany Silva; Limongi, Suelly Cecília Olivan; Shahnaz, Navid; Carvallo, Renata Mota Mamede

2016-08-01

Children with Down syndrome (DS) have a high incidence of middle ear disorders and congenital abnormalities of the external, middle and inner ear. Energy reflectance (ER), a wideband acoustic immittance (WAI) measurement parameter, can measure the sound energy reflected or absorbed in the ear canal over a wider range of frequencies more efficiently and faster than conventional single-tone 226 Hz tympanometry. The aim of the present study was to compare the WAI measurements of children with DS with those of typically developing, normal-hearing children according to their tympanometric findings. Four groups of children with Down syndrome (age range: 2 years and 4 months to 16 years and 3 months; mean age: 8.5 yr) with normal tympanograms (19 ears), flat tympanograms (13 ears), mild negative pressure tympanograms (6 ears between -100 and -199 daPa at the admittance peak) and severe negative pressure tympanograms (4 ears at -200 daPa or lower at the admittance peak) were assessed. All findings were compared with data obtained from 21 ears of a healthy control group (age range: 3 years and 1 month to 13 years and 11 months; mean age: 7.9 yr). The subjects underwent tympanometry with a 226-Hz probe tone frequency and ER measurements along the 200-6,000 Hz range with a chirp stimulus using the Middle-Ear Power Analyzer (MEPA3 - HearID) by Mimosa Acoustics (Champaign, IL), software, version 3.3 [38]. Statistically significant differences were observed in the ER curves for some comparisons between the studied groups. There was also a negative correlation between the static acoustic admittance at the tympanic membrane level and ER measured with a chirp stimulus at 500 and 1,000 Hz. The discriminant analysis technique, which used a chirp stimulus at 1,000 and 1,600 Hz to classify the participants' data based on ER values, achieved a correct classification rate of 59.52% for participants with DS. While groups with abnormal middle ear status, as indicated by tympanometry, showed higher ER values compared to the DS tymp A group and the control group, similar reflectance curves were observed between control group and the DS tymp A group. WAI shows promise as a clinical diagnostic tool in investigating the impact of middle ear disorders in DS group. However, further research is required to investigate this issue in narrower age range group and a larger sample size. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

In vitro activity of an ear rinse containing tromethamine, EDTA, benzyl alcohol and 0.1% ketoconazole on Malassezia organisms from dogs with otitis externa.

PubMed

Cole, Lynette K; Luu, Dao H; Rajala-Schultz, Paivi J; Meadows, Cheyney; Torres, Audrey H

2007-04-01

The purpose of this study was to evaluate the in vitro activity of an ear rinse containing tromethamine, EDTA, benzyl alcohol and 0.1% ketoconazole in purified water on Malassezia organisms from dogs with otitis externa. Malassezia organisms were collected from ear swab samples from the external ear canal of 19 dogs with otitis externa plus one control strain of Malassezia pachydermatis. Three test solutions were evaluated: ER (EDTA, tromethamine, benzyl alcohol), ER + keto (EDTA, tromethamine, benzyl alcohol, ketoconazole), and H2O (purified water). Ten-millilitre aliquots of each test solution was transferred into 20 tubes and inoculated with one of the isolates (1 tube per isolate: 19 clinical and 1 control strain). Samples were retrieved from each tube at five time points (0, 15, 30, 45 and 60 min), transferred to Petri dishes, mixed with Sabouraud dextrose agar supplemented with 0.5% Tween 80 and incubated. Following incubation, the plates were examined for growth and colonies counted as colony-forming units per millilitre. The data were analysed using a repeated measures analysis, with pair-wise comparisons of solution-time combinations. There was a significant reduction in Malassezia growth in ER + keto at all time points (P < 0.0001) compared to time zero. Neither ER nor H2O had any effect on the growth of Malassezia. ER + keto was significantly more effective in reducing Malassezia growth (P < 0.0001) at all time points compared to both ER and H2O. ER + keto may be useful in the treatment of Malassezia otitis externa. Future studies should be performed to evaluate the in vivo efficacy of ER + keto as treatment for otic infections caused by Malassezia.

Tympanomastoid cholesterol granulomas: Immunohistochemical evaluation of angiogenesis.

PubMed

Iannella, Giannicola; Di Gioia, Cira; Carletti, Raffaella; Magliulo, Giuseppe

2017-08-01

This study investigates the immunohistochemical expression of vascular endothelial growth factor (VEGF) and CD34 in patients treated for middle ear and mastoid cholesterol granulomas to evaluate the angiogenesis and vascularization of this type of lesion. A correlation between the immunohistochemical data and the radiological and intraoperative evidence of temporal bone marrow invasion and blood source connection was performed to validate this hypothesis. Retrospective study. Immunohistochemical expression of VEGF and CD34 in a group of 16 patients surgically treated for cholesterol granuloma was examined. Middle ear cholesteatomas with normal middle ear mucosa and external auditory canal skin were used as the control groups. The radiological and intraoperative features of cholesterol granulomas were also examined. In endothelial cells, there was an increased expression of angiogenetic growth factor receptors in all the cholesterol granulomas in this study. The quantitative analysis of VEGF showed a mean value of 37.5, whereas the CD34 quantitative analysis gave a mean value of 6.8. Seven patients presented radiological or intraoperative evidence of bone marrow invasion, hematopoietic potentialities, or blood source connections that might support the bleeding theory. In all of these cases there was computed tomography or intraoperative evidence of bone erosion of the middle ear and/or temporal bone structures. The mean values of VEGF and CD34 were 41.1 and 7.7, respectively. High values of VEGF and CD34 are present in patients with cholesterol granulomas. Upregulation of VEGF and CD34 is indicative of a remarkable angiogenesis and a widespread vascular concentration in cholesterol granulomas. 3b. Laryngoscope, 127:E283-E290, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

Intratympanic hemorrhage and concussion in a football offensive lineman.

PubMed

Waninger, Kevin N; Gloyeske, Brian M; Hauth, John M; Vanic, Keith A; Yen, David M

2014-03-01

A 26-year-old arena football lineman participating in a "bull in the ring" blocking and tackling drill was blindsided by an opposing teammate. He sustained a direct helmet-to-helmet blow to the right temporal area. This case describes a unique mechanism of ear barotrauma (intratympanic hemorrhage) and concussion caused by helmet-to-helmet contact in American football. Initial sideline evaluation revealed mild headache, confusion, dizziness, photophobia, and tinnitus, all consistent with a concussion diagnosis. Physical examination revealed a large postauricular contusion over the right mastoid process and diffuse right intratympanic hemorrhage on examination. No hemotympanum or effusion of the middle ear was noted. Abnormalities were seen on vestibular testing and visual accommodation and convergence testing. Computed tomography and magnetic resonance imaging were performed with attention to the temporal bones and were normal. Neuropsychological testing was abnormal compared to baseline. Audiology testing was within normal limits. Diagnosis was intratympanic hemorrhage secondary to barotrauma caused by helmet-to-helmet contact, with mastoid contusion and season-ending concussion. The tympanic membrane (TM) is a highly vascular membrane that is very sensitive to variations of atmospheric pressure. Overpressure can enter the external auditory canal, stretching and displacing the TM medially and causing injury to the tympanic membrane secondary to barotrauma. This concussed football player was never able to return to play due to his postconcussive symptoms. He had no residual hearing or ear problems. Copyright © 2014 Elsevier Inc. All rights reserved.

Anatomic measurements of the posterior tympanum related to the round window vibroplasty in congenital aural atresia and stenosis patients.

PubMed

Chen, Keguang; Yin, Dongming; Lyu, Huiying; Yang, Lin; Zhang, Tianyu; Dai, Peidong

2016-01-01

With the aggravation of the external auditory canal malformation, the size of extra-niche fossa became smaller, providing concrete data and valuable information for the better design, selecting and safer implantation of the transducer in the area of round window niche. Three-dimensional measurements and assessments before surgery might be helpful for a safer surgical approach and implantation of a vibrant soundbridge. The aim of this study was to investigate whether differences exist in the morphology of the posterior tympanum related to the round window vibroplasty among congenital aural atresia (CAA), congenital aural stenosis (CAS), and a normal control group, and to analyze its effect on the round window implantation of vibrant soundbridge. CT images of 10 normal subjects (20 ears), 27 CAS patients (30 ears), and 25 CAA patients (30 ears) were analyzed. The depth and the size of outside fossa of round window niche related to the round window vibroplasty (extra-niche fossa)and the distances between the center of round window niche and extra-niche fossa were calculated based on three-dimensional reconstruction using mimics software. Finally, the data were analyzed statistically. The size of extra-niche fossa in the atresia group was smaller than in the stenosis group (p < 0.05); furthermore, the size of extra-niche fossa in the stenosis group was smaller than that of the control group (p < 0.05). There was no statistically significant difference of the depth of extra-niche fossa among different groups.

Active transcutaneous bone conduction implant: audiological results in paediatric patients with bilateral microtia associated with external auditory canal atresia.

PubMed

Bravo-Torres, Sofía; Der-Mussa, Carolina; Fuentes-López, Eduardo

2018-01-01

To describe, in terms of functional gain and word recognition, the audiological results of patients under 18 years of age implanted with the active bone conduction implant, Bonebridge™. Retrospective case studies conducted by reviewing the medical records of patients receiving implants between 2014 and 2016 in the public health sector in Chile. All patients implanted with the Bonebridge were included (N = 15). Individuals who had bilateral conductive hearing loss, secondary to external ear malformations, were considered as candidates. The average hearing threshold one month after switch on was 25.2 dB (95%CI 23.5-26.9). Hearing thresholds between 0.5 and 4 kHz were better when compared with bone conduction hearing aids. Best performance was observed at 4 kHz, where improvements to hearing were observed throughout the adaptation process. There was evidence of a significant increase in the recognition of monosyllables. The Bonebridge implant showed improvements to hearing thresholds and word recognition in paediatric patients with congenital conductive hearing loss.

Middle Ear Infections and Ear Tube Surgery (For Parents)

MedlinePlus

... Infection? Swimmer's Ear Perforated Eardrum Hearing Impairment Swimmer's Ear (External ... All information on KidsHealth® is for educational purposes only. For specific medical advice, diagnoses, and treatment, ...

Astronaut John Glenn tests balance mechanism performance

NASA Image and Video Library

1962-02-01

S64-14849 (1962) --- Astronaut John H. Glenn Jr.'s balance mechanism (semi-circular-canals) is tested by running cool water into his ear and measuring effect on eye motions (nystagmus). Photo credit: NASA

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

PubMed

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.

Can I Prevent Ear Infections When My Child Swims? (For Parents)

MedlinePlus

... Ear Your Ears Perforated Eardrum What's Earwax? Swimmer's Ear (External ... All information on KidsHealth® is for educational purposes only. For specific medical advice, diagnoses, and treatment, ...

Ear asymmetries in middle-ear, cochlear, and brainstem responses in human infants

PubMed Central

Keefe, Douglas H.; Gorga, Michael P.; Jesteadt, Walt; Smith, Lynette M.

2008-01-01

In 2004, Sininger and Cone-Wesson examined asymmetries in the signal-to-noise ratio (SNR) of otoacoustic emissions (OAE) in infants, reporting that distortion-product (DP)OAE SNR was larger in the left ear, whereas transient-evoked (TE)OAE SNR was larger in the right. They proposed that cochlear and brainstem asymmetries facilitate development of brain-hemispheric specialization for sound processing. Similarly, in 2006 Sininger and Cone-Wesson described ear asymmetries mainly favoring the right ear in infant auditory brainstem responses (ABRs). The present study analyzed 2640 infant responses to further explore these effects. Ear differences in OAE SNR, signal, and noise were evaluated separately and across frequencies (1.5, 2, 3, and 4 kHz), and ABR asymmetries were compared with cochlear asymmetries. Analyses of ear-canal reflectance and admittance showed that asymmetries in middle-ear functioning did not explain cochlear and brainstem asymmetries. Current results are consistent with earlier studies showing right-ear dominance for TEOAE and ABR. Noise levels were higher in the right ear for OAEs and ABRs, causing ear asymmetries in SNR to differ from those in signal level. No left-ear dominance for DPOAE signal was observed. These results do not support a theory that ear asymmetries in cochlear processing mimic hemispheric brain specialization for auditory processing. PMID:18345839

Facial palsy following trauma to the external ear: 3 case reports.

PubMed

Vögelin, E; Jones, B M

1997-12-01

We report two children and a young adult who developed unilateral facial palsy shortly after injury to the external ear. In two instances the paralysis followed a prominent ear correction and in the other a laceration to the concha. The trauma-triggered facial palsy was most likely idiopathic although the anatomy of the facial nerve near the ear leads one to speculate on a possible pathway of a virally induced palsy (Bell's palsy). Each patient recovered over a period of 6 months.

CT detection of facial canal dehiscence and semicircular canal fistula: Comparison with surgical findings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fuse, Takeo; Tada, Yuichiro; Aoyagi, Masaru

1996-03-01

The purpose of this study was to determine the accuracy of high resolution CT (HRCT) in the detection of facial canal dehiscence and semicircular canal fistula, the preoperative evaluation of both of which is clinically very important for ear surgery. We retrospectively reviewed the HRCT findings in 61 patients who underwent mastoidectomy at Yamagata University between 1989 and 1993. The HRCT images were obtained in the axial and semicoronal planes using 1 mm slice thickness and 1 mm intersection gap. In 46 (75%) of the 61 patients, the HRCT image-based assessment of the facial canal dehiscence coincided with the surgicalmore » findings. The data for the facial canal revealed sensitivity of 66% and specificity of 84%. For semicircular canal fistula. in 59 (97%) of the 61 patients, the HRCT image-based assessment and the surgical findings coincided. The image-based assessment in the remaining two patients, who both had massive cholesteatoma, was false-positive. HRCT is useful in the diagnosis of facial canal dehiscence and labyrinthine fistula, but its limitations should also be recognized. 12 refs., 3 figs., 6 tabs.« less

3D finite element model of the chinchilla ear for characterizing middle ear functions

PubMed Central

Wang, Xuelin; Gan, Rong Z.

2016-01-01

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. PMID:26785845

Intracochlear pressure measurements during acoustic shock wave exposure.

PubMed

Greene, Nathaniel T; Alhussaini, Mohamed A; Easter, James R; Argo, Theodore F; Walilko, Tim; Tollin, Daniel J

2018-05-19

Injuries to the peripheral auditory system are among the most common results of high intensity impulsive acoustic exposure. Prior studies of high intensity sound transmission by the ossicular chain have relied upon measurements in animal models, measurements at more moderate sound levels (i.e. < 130 dB SPL), and/or measured responses to steady-state noise. Here, we directly measure intracochlear pressure in human cadaveric temporal bones, with fiber optic pressure sensors placed in scala vestibuli (SV) and tympani (ST), during exposure to shock waves with peak positive pressures between ∼7 and 83 kPa. Eight full-cephalic human cadaver heads were exposed, face-on, to acoustic shock waves in a 45 cm diameter shock tube. Specimens were exposed to impulses with nominal peak overpressures of 7, 28, 55, & 83 kPa (171, 183, 189, & 192 dB pSPL), measured in the free field adjacent to the forehead. Specimens were prepared bilaterally by mastoidectomy and extended facial recess to expose the ossicular chain. Ear canal (EAC), middle ear, and intracochlear sound pressure levels were measured with fiber-optic pressure sensors. Surface-mounted sensors measured SPL and skull strain near the opening of each EAC and at the forehead. Measurements on the forehead showed incident peak pressures approximately twice that measured by adjacent free-field and EAC entrance sensors, as expected based on the sensor orientation (normal vs tangential to the shock wave propagation). At 7 kPa, EAC pressure showed gain, calculated from the frequency spectra, consistent with the ear canal resonance, and gain in the intracochlear pressures (normalized to the EAC pressure) were consistent with (though somewhat lower than) previously reported middle ear transfer functions. Responses to higher intensity impulses tended to show lower intracochlear gain relative to EAC, suggesting sound transmission efficiency along the ossicular chain is reduced at high intensities. Tympanic membrane (TM) rupture was observed following nearly every exposure 55 kPa or higher. Intracochlear pressures reveal lower middle-ear transfer function magnitudes (i.e. reduced gain relative to the ear canal) for high sound pressure levels, thus revealing lower than expected cochlear exposure based on extrapolation from cochlear pressures measured at more moderate sound levels. These results are consistent with lowered transmissivity of the ossicular chain at high intensities, and are consistent with our prior report measuring middle ear transfer functions in human cadaveric temporal bones with high intensity tone pips. Copyright © 2018 Elsevier B.V. All rights reserved.

Self-ear cleaning practices and the associated risk of ear injuries and ear-related symptoms in a group of university students.

PubMed

Khan, Nasim Banu; Thaver, Sivashnee; Govender, Samantha Marlene

2017-12-31

Self-ear cleaning is the insertion of objects into the ear canal to clean it, a widespread practice that has the potential to compromise its integrity as a natural, selfcleansing mechanism, and a risk factor for possible injuries. The practice is common among young adults and highest in university than any other graduates. This study aimed to determine the self-ear cleaning practices and associated risk of injury and related symptoms in undergraduate students at KwaZulu-Natal University. The descriptive survey utilized a self-administered questionnaire. Of the 206 participants that responded, 98% engaged in self-ear cleaning, with 75% indicating that it was beneficial. The commonest method (79.6%) being the use of cotton buds, with an associated injury rate of 2.4%. There was no statistically significant associations between those who used or did not use cotton buds and the symptoms experienced. The complications indicate that self-ear cleaning does pose a risk for injury, necessitating more community information and education.

Study of the occlusion effect induced by an earplug: Numerical modelling and experimental validation

NASA Astrophysics Data System (ADS)

Brummund, Martin

Despite existing limits for occupational noise exposure, professional hearing loss remains a high priority problem both in Quebec and worldwide. Several approaches exist to protect workers from harmful noise levels. The most frequently employed short term solution includes the distribution of hearing protection devices (HPD) such as earplugs and ear muffs. While HPDs offer an inexpensive (e.g. direct cost) and efficient means of protection workers often only tend to wear HPDs for limited amounts of time and, thus, remain at risk of developing professional hearing loss. Discomfort while using HPDs contributes to HPD underutilization and non-use. Two more general categories of discomfort can be distinguished. The category physical discomfort includes, for instance, problems such as heating of the ear and irritation of the ear canal that that occur upon earplug insertion. The category auditory discomfort refers to alterations in the auditory perception of sounds and one's own voice as well as hindered workplace communications. One important auditory discomfort that promotes HPD non-use is the occlusion effect. The occlusion effect occurs upon earplug insertion and describes sound amplification phenomena in the occluded ear canal at the low frequencies. The sound amplification is both perceivable and measurable (e.g., open and occluded sound pressure levels, hearing threshold shift). Additionally, the occlusion effect causes the HPD wearer to perceive his/her own voice as being distorted (e.g. hollow sounding) and physiological noises (e.g. respiration, blood circulation) are amplified also subsequent to earplug insertion. Reducing the occlusion effect has the potential to increase the auditory comfort of HPDs and could help preventing occupational hearing loss in the future. In order to improve this and other shortcomings observed with currently existing HPDs a large research collaboration between the Robert-Sauve research institute in occupational health and safety (IRSST) and the Ecole de technologie superieure (ETS) has been launched. The present study represents a part of this collaboration and aims at studying the occlusion effect of the system earplug - ear canal through the development of novel numerical models and experimental methods. (Abstract shortened by UMI.).

The effect of superior canal dehiscence on cochlear potential in response to air-conducted stimuli in chinchilla

PubMed Central

Songer, Jocelyn E.; Rosowski, John J.

2006-01-01

A superior semicircular canal dehiscence (SCD) is a break or hole in the bony wall of the superior semicircular canal. Patients with SCD syndrome present with a variety of symptoms: some with vestibular symptoms, others with auditory symptoms (including low-frequency conductive hearing loss) and yet others with both. We are interested in whether or not mechanically altering the superior canal by introducing a dehiscence is sufficient to cause the low-frequency conductive hearing loss associated with SCD syndrome. We evaluated the effect of a surgically introduced dehiscence on auditory responses to air-conducted (AC) stimuli in 11 chinchilla ears. Cochlear potential (CP) was recorded at the round-window before and after a dehiscence was introduced. In each ear, a decrease in CP in response to low frequency (<2 kHz) sound stimuli was observed after the introduction of the dehiscence. The dehiscence was then patched with cyanoacrylate glue leading to a reversal of the dehiscence-induced changes in CP. The reversible decrease in auditory sensitivity observed in chinchilla is consistent with the elevated AC thresholds observed in patients with SCD. According to the ‘third-window’ hypothesis the SCD shunts sound-induced stapes velocity away from the cochlea, resulting in decreased auditory sensitivity to AC sounds. The data collected in this study are consistent with predictions of this hypothesis. PMID:16150562

Lateral semicircular canal osteoma presenting as chronic postaural fistula.

PubMed

Gill, Charn; Muzaffar, Jameel; Kumar, Raghu Sampath; Irving, Richard

2018-05-12

Temporal bone osteoma is an unusual pathology which can occur by birth or can be acquired and mostly involves the tympanomastoid segment of the temporal bone. Osteomas arising from the otic capsule are extremely rare, and there has been only one other report of a lateral semicircular canal osteoma in the literature. We report a similar case of an acquired lateral canal osteoma which presented as a chronic postaural fistula in an ear previously operated for paediatric cholesteatoma. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Insights into horizontal canal benign paroxysmal positional vertigo from a human case report.

PubMed

Aron, Margaret; Bance, Manohar

2013-12-01

For horizontal canal benign paroxysmal positional vertigo, determination of the pathologic side is difficult and based on many physiological assumptions. This article reports findings on a patient who had one dysfunctional inner ear and who presented with horizontal canal benign paroxysmal positional vertigo, giving us a relatively pure model for observing nystagmus arising in a subject in whom the affected side is known a priori. It is an interesting human model corroborating theories of nystagmus generation in this pathology and also serves to validate Ewald's second law in a living human subject. Copyright © 2013 The American Laryngological, Rhinological and Otological Society, Inc.

Spatial Hearing with Incongruent Visual or Auditory Room Cues

PubMed Central

Gil-Carvajal, Juan C.; Cubick, Jens; Santurette, Sébastien; Dau, Torsten

2016-01-01

In day-to-day life, humans usually perceive the location of sound sources as outside their heads. This externalized auditory spatial perception can be reproduced through headphones by recreating the sound pressure generated by the source at the listener’s eardrums. This requires the acoustical features of the recording environment and listener’s anatomy to be recorded at the listener’s ear canals. Although the resulting auditory images can be indistinguishable from real-world sources, their externalization may be less robust when the playback and recording environments differ. Here we tested whether a mismatch between playback and recording room reduces perceived distance, azimuthal direction, and compactness of the auditory image, and whether this is mostly due to incongruent auditory cues or to expectations generated from the visual impression of the room. Perceived distance ratings decreased significantly when collected in a more reverberant environment than the recording room, whereas azimuthal direction and compactness remained room independent. Moreover, modifying visual room-related cues had no effect on these three attributes, while incongruent auditory room-related cues between the recording and playback room did affect distance perception. Consequently, the external perception of virtual sounds depends on the degree of congruency between the acoustical features of the environment and the stimuli. PMID:27853290

Improved tympanic thermometer based on a fiber optic infrared radiometer and an otoscope and its use as a new diagnostic tool for acute otitis media

NASA Astrophysics Data System (ADS)

Fishman, Gadi; DeRowe, Ari; Ophir, Eyal; Scharf, Vered; Shabtai, Abraham; Ophir, Dov; Katzir, Abraham

1999-06-01

Clinical diagnosis of acute otitis media (AOM) in children is not easy. It was assumed that there is a difference ΔT between the Tympanic Membrane (TM) temperatures in the two ears in unilateral AOM and that an accurate measurement of ΔT may improve the diagnosis accuracy. An IR transmitting fiber, made of AgClBr, was coupled into a hand held otoscope and was used for the non-contact (radiometric) measurements of TT, the TM temperature. Experiments were carried out, first, on a laboratory model that simulated the human ear, including an artificial tympanic membrane and an artificial ear canal. Measurements carried out using commercially available tympanic thermometers shown that the temperature Tc of the ear canal affected the results. Tc did not affect the fiberoptic radiometer, and this device accurately measured the true temperature, TT of the tympanic membrane. A prospective blinded sampling of the TM temperature was then performed on 48 children with suspected AOM. The mean temperature difference between the ears, for children with unilateral AOM was ΔT = (0.68 +/- 0.27)°C. For children with bilateral AOM it was ΔT = (0.14+/-0.10)°C (p<0.001). It was demonstrated that afor unilateral AOM the difference ΔT was proportional to the systemic temperature. In conclusion, the fiberoptic interferometric measurements of the TM can be a useful non-invasive diagnostic tool for AOM, when combined with other data.

Innervation of the cow's inner ear derived from micro-computed tomography

NASA Astrophysics Data System (ADS)

Costeur, Loic; Mennecart, Bastien; Khimchenko, Anna; Müller, Bert; Schulz, Georg

2017-09-01

The innervation of the inner ear has been thoroughly investigated in humans and in some animal models such as the guinea pig, the rabbit, the cat, the dog, the rat, the pig and some monkeys. Ruminant inner ears are still poorly known and their innervation was never investigated despite its potential interest in phylogenetic reconstructions. Following earlier works on the ontogeny of the cow's ear, we expand our understanding of this structure by reconstructing the fine innervation pattern of the inner ear of the cow in two ontogenetic stages, at 7 months gestation and at an adult age. Since we work on dry skeletal specimens, only the endocast of the innervation inside the petrosal bone was reconstructed up to the internal acoustic meatus. The paths of the facial and vestibulocochlear nerves could be reconstructed together with that of the spiral ganglion canal. The nerves have a very fibrous pattern. The bony cavities of the ampular and utricular branches of the vestibulocochlear nerve could also be reconstructed. Our observations confirm that not all bony structures are present in foetal stages since the branch of cranial nerve VII is not visible on the foetus but very broad on the adult stage. The fibrous pattern within the modiolus connecting the spiral canal to the cochlear nerve is also less dense than in the adult stage. The shape of the branch of cranial nerve VII is very broad in the cow ending in a large hiatus Fallopii; this, together with the above-mentioned particularities, could constitute relevant observations for phylogenetical purposes when more data will be made available.

Caloric stimulation

MedlinePlus

... differences in temperature to diagnose damage to the acoustic nerve. This is the nerve that is involved ... This test stimulates your acoustic nerve by delivering cold or warm water or air into your ear canal. When cold water or air enters your ...

The influence of a time-varying least squares parametric model when estimating SFOAEs evoked with swept-frequency tones

NASA Astrophysics Data System (ADS)

Hajicek, Joshua J.; Selesnick, Ivan W.; Henin, Simon; Talmadge, Carrick L.; Long, Glenis R.

2018-05-01

Stimulus frequency otoacoustic emissions (SFOAEs) were evoked and estimated using swept-frequency tones with and without the use of swept suppressor tones. SFOAEs were estimated using a least-squares fitting procedure. The estimated SFOAEs for the two paradigms (with- and without-suppression) were similar in amplitude and phase. The fitting procedure minimizes the square error between a parametric model of total ear-canal pressure (with unknown amplitudes and phases) and ear-canal pressure acquired during each paradigm. Modifying the parametric model to allow SFOAE amplitude and phase to vary over time revealed additional amplitude and phase fine structure in the without-suppressor, but not the with-suppressor paradigm. The use of a time-varying parametric model to estimate SFOAEs without-suppression may provide additional information about cochlear mechanics not available when using a with-suppressor paradigm.

Eye size and visual acuity influence vestibular anatomy in mammals.

PubMed

Kemp, Addison D; Christopher Kirk, E

2014-04-01

The semicircular canals of the inner ear detect head rotations and trigger compensatory movements that stabilize gaze and help maintain visual fixation. Mammals with large eyes and high visual acuity require precise gaze stabilization mechanisms because they experience diminished visual functionality at low thresholds of uncompensated motion. Because semicircular canal radius of curvature is a primary determinant of canal sensitivity, species with large canal radii are expected to be capable of more precise gaze stabilization than species with small canal radii. Here, we examine the relationship between mean semicircular canal radius of curvature, eye size, and visual acuity in a large sample of mammals. Our results demonstrate that eye size and visual acuity both explain a significant proportion of the variance in mean canal radius of curvature after statistically controlling for the effects of body mass and phylogeny. These findings suggest that variation in mean semicircular canal radius of curvature among mammals is partly the result of selection for improved gaze stabilization in species with large eyes and acute vision. Our results also provide a possible functional explanation for the small semicircular canal radii of fossorial mammals and plesiadapiforms. Copyright © 2014 Wiley Periodicals, Inc.

Real-time estimation of horizontal gaze angle by saccade integration using in-ear electrooculography

PubMed Central

2018-01-01

The manuscript proposes and evaluates a real-time algorithm for estimating eye gaze angle based solely on single-channel electrooculography (EOG), which can be obtained directly from the ear canal using conductive ear moulds. In contrast to conventional high-pass filtering, we used an algorithm that calculates absolute eye gaze angle via statistical analysis of detected saccades. The estimated eye positions of the new algorithm were still noisy. However, the performance in terms of Pearson product-moment correlation coefficients was significantly better than the conventional approach in some instances. The results suggest that in-ear EOG signals captured with conductive ear moulds could serve as a basis for light-weight and portable horizontal eye gaze angle estimation suitable for a broad range of applications. For instance, for hearing aids to steer the directivity of microphones in the direction of the user’s eye gaze. PMID:29304120

Real-time estimation of horizontal gaze angle by saccade integration using in-ear electrooculography.

PubMed

Hládek, Ľuboš; Porr, Bernd; Brimijoin, W Owen

2018-01-01

The manuscript proposes and evaluates a real-time algorithm for estimating eye gaze angle based solely on single-channel electrooculography (EOG), which can be obtained directly from the ear canal using conductive ear moulds. In contrast to conventional high-pass filtering, we used an algorithm that calculates absolute eye gaze angle via statistical analysis of detected saccades. The estimated eye positions of the new algorithm were still noisy. However, the performance in terms of Pearson product-moment correlation coefficients was significantly better than the conventional approach in some instances. The results suggest that in-ear EOG signals captured with conductive ear moulds could serve as a basis for light-weight and portable horizontal eye gaze angle estimation suitable for a broad range of applications. For instance, for hearing aids to steer the directivity of microphones in the direction of the user's eye gaze.

Middle ear abnormalities in Van Maldergem syndrome.

PubMed

Verheij, Emmy; Thomeer, Henricus G X M; Pameijer, Frank A; Topsakal, Vedat

2017-01-01

Van Maldergem syndrome (VMS) is a very rare syndrome that was first described in 1992. The main features of this syndrome comprise intellectual disability, blepharo-naso-facial malformation, and hand anomalies. Almost all nine described patients have been shown to be affected by conductive hearing impairment attributed to microtia, and atresia of the outer ear canal. Here, we present a VMS patient with congenital malformations of the middle ear as the main reason for severe conductive bilateral hearing impairment. To our knowledge, this is the first report to describe middle ear abnormalities in VMS. These malformations were seen on high resolution Computed Tomography scanning and during an exploratory tympanotomy. Due to the severity of the middle ear abnormalities and the risk for facial nerve damage, the patient was not offered an ossicular chain reconstruction but a bone conduction device after this exploratory tympanotomy. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Scala vestibuli pressure and three-dimensional stapes velocity measured in direct succession in gerbil.

PubMed

Decraemer, W F; de La Rochefoucauld, O; Dong, W; Khanna, S M; Dirckx, J J J; Olson, E S

2007-05-01

It was shown that the mode of vibration of the stapes has a predominant piston component but rotations producing tilt of the footplate are also present. Tilt and piston components vary with frequency. Separately it was shown that the pressure gain between ear canal and scala vestibuli was a remarkably flat and smooth function of frequency. Is tilt functional contributing to the pressure in the scala vestibuli and helping in smoothing the pressure gain? In experiments on gerbil the pressure in the scala vestibuli directly behind the footplate was measured while recording simultaneously the pressure produced by the sound source in the ear canal. Successively the three-dimensional motion of the stapes was measured in the same animal. Combining the vibration measurements with an anatomical shape measurement from a micro-CT (CT: computed tomography) scan the piston-like motion and the tilt of the footplate was calculated and correlated to the corresponding scala vestibuli pressure curves. No evidence was found for the hypothesis that dips in the piston velocity are filled by peaks in tilt in a systematic way to produce a smooth middle ear pressure gain function. The present data allowed calculations of the individual cochlear input impedances.

Privacy-protected biometric templates: acoustic ear identification

NASA Astrophysics Data System (ADS)

Tuyls, Pim T.; Verbitskiy, Evgeny; Ignatenko, Tanya; Schobben, Daniel; Akkermans, Ton H.

2004-08-01

Unique Biometric Identifiers offer a very convenient way for human identification and authentication. In contrast to passwords they have hence the advantage that they can not be forgotten or lost. In order to set-up a biometric identification/authentication system, reference data have to be stored in a central database. As biometric identifiers are unique for a human being, the derived templates comprise unique, sensitive and therefore private information about a person. This is why many people are reluctant to accept a system based on biometric identification. Consequently, the stored templates have to be handled with care and protected against misuse [1, 2, 3, 4, 5, 6]. It is clear that techniques from cryptography can be used to achieve privacy. However, as biometric data are noisy, and cryptographic functions are by construction very sensitive to small changes in their input, and hence one can not apply those crypto techniques straightforwardly. In this paper we show the feasibility of the techniques developed in [5], [6] by applying them to experimental biometric data. As biometric identifier we have choosen the shape of the inner ear-canal, which is obtained by measuring the headphone-to-ear-canal Transfer Functions (HpTFs) which are known to be person dependent [7].

[Magnetic resonance imaging study and cochlear implantation in post-meningitic deaf patients].

PubMed

Liu, Xiuli; Yao, Yiwen; He, Guili; Zhai, Lijie

2004-07-01

To investigate the clinical application of magnetic resonance imaging (MRI) in post-meningitic patients and its impact on surgical decision. The pre-operative MRI data and auditory brainstem response (ABR) examination of five post-meningitic patients were studied. They were implanted with cochleas. The interval between the onset of bacterial meningitis and the hearing loss was (15.8 +/- 15.0)d and it was longer in children than adults. Five ears showed membranous cochlear labyrinth abnormality; 3 ears had vestibule vestibule abnormality; 8 ears demonstrated semicircular canal abnormality on MRI examinations in totally 10 ears. The mean hearing threshold of 10 ears was (102.0 +/- 7.1)dB HL,that of the operated ears was (98.0 +/- 5.7)dB HL and that of the un-operated ears was (106.0 +/- 6.5)dB HL. It was (15.8 +/- 15.0)d from the bacterial meningitis onset to hearing loss. The interval is longer in children than adults. There were 3 ears that electrodes could not be inserted completely. The bacterial meningitis may cause the abnormalities of inner ears and the MRI before surgery is essential for the pre-operative planning of cochlear implant.

Effect of Probe Tube Insertion Depth on Spectral Measures of Speech

PubMed Central

Caldwell, Marc; Souza, Pamela E.; Tremblay, Kelly L.

2006-01-01

This study investigated how depth variations in the tip of the probe tube affected spectral measures of speech recorded in the external ear canal. Consonant-vowel nonsense syllables were recorded with a probe tube microphone system in 10 adult participants with normal middle ear function. Recordings were made with the probe tube tip placed 1 mm, 5 mm, and 10 mm beyond the medial tip of a custom earmold. The effect of probe depth was evaluated on spectral levels (one-third octave and one-twelfth octave band). Extending the probe tube 10 mm past the medial tip of the earmold gave the most accurate results, with relatively lower sound levels for either the 1-mm or 5-mm insertion depth. In general, the effect of insertion depth was minimal at frequencies below 3 to 4 kHz, although this varied with the specific phoneme and the width of the analysis bands. The authors found no significant difference between 1- and 5-mm insertion depths, suggesting that as long as the tip of the probe tube is sufficiently close to the tympanic membrane to capture the highest frequency of interest, it makes little difference if it is less than 5 mm beyond the earmold tip. PMID:16959735

Field experiments using SPEAR: a speech control system for UGVs

NASA Astrophysics Data System (ADS)

Chhatpar, Siddharth R.; Blanco, Chris; Czerniak, Jeffrey; Hoffman, Orin; Juneja, Amit; Pruthi, Tarun; Liu, Dongqing; Karlsen, Robert; Brown, Jonathan

2009-05-01

This paper reports on a Field Experiment carried out by the Human Research and Engineering Directorate at Ft. Benning to evaluate the efficacy of using speech to control an Unmanned Ground Vehicle (UGV) concurrently with a handcontroller. The SPEAR system, developed by Think-A-Move, provides speech-control of UGVs. The system picks up user-speech in the ear canal with an in-ear microphone. This property allows it to work efficiently in high-noise environments, where traditional speech systems, employing external microphones, fail. It has been integrated with an iRobot PackBot 510 with EOD kit. The integrated system allows the hand-controller to be supplemented with speech for concurrent control. At Ft. Benning, the integrated system was tested by soldiers from the Officer Candidate School. The Experiment had dual focus: 1) Quantitative measurement of the time taken to complete each station and the cognitive load on users; 2) Qualitative evaluation of ease-of-use and ergonomics through soldier-feedback. Also of significant benefit to Think-A-Move was soldier-feedback on the speech-command vocabulary employed: What spoken commands are intuitive, and how the commands should be executed, e.g., limited-motion vs. unlimited-motion commands. Overall results from the Experiment are reported in the paper.

Treatment of otitis media by transtympanic delivery of antibiotics

PubMed Central

Yang, Rong; Sabharwal, Vishakha; Okonkwo, Obiajulu S.; Shlykova, Nadya; Tong, Rong; Lin, Lily Yun; Wang, Weiping; Guo, Shutao; Rosowski, John J.; Pelton, Stephen I.; Kohane, Daniel S.

2017-01-01

Otitis media is the most common reason U.S. children receive antibiotics. The requisite 7- to 10-day course of oral antibiotics can be challenging to deliver in children, entails potential systemic toxicity, and encourages selection of antimicrobial-resistant bacteria. We developed a drug delivery system that, when applied once to the tympanic membrane through the external auditory canal, delivers an entire course of antimicrobial therapy to the middle ear. A penta-block copolymer poloxamer 407–polybutylphosphoester (P407-PBP) was designed to flow easily during application and then to form a mechanically strong hydrogel on the tympanic membrane. U.S. Food and Drug Administration–approved chemical permeation enhancers within the hydrogel assisted flux of the antibiotic ciprofloxacin across the membrane. This drug delivery system completely eradicated otitis media from nontypable Haemophilus influenzae (NTHi) in 10 of 10 chinchillas, whereas only 62.5% of animals receiving 1% ciprofloxacin alone had cleared the infection by day 7. The hydrogel system was biocompatible in the ear, and ciprofloxacin was undetectable systemically (in blood), confirming local drug delivery and activity. This fast-gelling hydrogel could improve compliance, minimize side effects, and prevent systemic distribution of antibiotics in one of the most common pediatric illnesses, possibly minimizing the development of antibiotic resistance. PMID:27629487

Cartilage conduction is characterized by vibrations of the cartilaginous portion of the ear canal.

PubMed

Nishimura, Tadashi; Hosoi, Hiroshi; Saito, Osamu; Miyamae, Ryosuke; Shimokura, Ryota; Yamanaka, Toshiaki; Kitahara, Tadashi; Levitt, Harry

2015-01-01

Cartilage conduction (CC) is a new form of sound transmission which is induced by a transducer being placed on the aural cartilage. Although the conventional forms of sound transmission to the cochlea are classified into air or bone conduction (AC or BC), previous study demonstrates that CC is not classified into AC or BC (Laryngoscope 124: 1214-1219). Next interesting issue is whether CC is a hybrid of AC and BC. Seven volunteers with normal hearing participated in this experiment. The threshold-shifts by water injection in the ear canal were measured. AC, BC, and CC thresholds at 0.5-4 kHz were measured in the 0%-, 40%-, and 80%-water injection conditions. In addition, CC thresholds were also measured for the 20%-, 60%-, 100%-, and overflowing-water injection conditions. The contributions of the vibrations of the cartilaginous portion were evaluated by the threshold-shifts. For AC and BC, the threshold-shifts by the water injection were 22.6-53.3 dB and within 14.9 dB at the frequency of 0.5-4 kHz, respectively. For CC, when the water was filled within the bony portion, the thresholds were elevated to the same degree as AC. When the water was additionally injected to reach the cartilaginous portion, the thresholds at 0.5 and 1 kHz dramatically decreased by 27.4 and 27.5 dB, respectively. In addition, despite blocking AC by the injected water, the CC thresholds in force level were remarkably lower than those for BC. The vibration of the cartilaginous portion contributes to the sound transmission, particularly in the low frequency range. Although the airborne sound is radiated into the ear canal in both BC and CC, the mechanism underlying its generation is different between them. CC generates airborne sound in the canal more efficiently than BC. The current findings suggest that CC is not a hybrid of AC and BC.

Cartilage Conduction Is Characterized by Vibrations of the Cartilaginous Portion of the Ear Canal

PubMed Central

Nishimura, Tadashi; Hosoi, Hiroshi; Saito, Osamu; Miyamae, Ryosuke; Shimokura, Ryota; Yamanaka, Toshiaki; Kitahara, Tadashi; Levitt, Harry

2015-01-01

Cartilage conduction (CC) is a new form of sound transmission which is induced by a transducer being placed on the aural cartilage. Although the conventional forms of sound transmission to the cochlea are classified into air or bone conduction (AC or BC), previous study demonstrates that CC is not classified into AC or BC (Laryngoscope 124: 1214–1219). Next interesting issue is whether CC is a hybrid of AC and BC. Seven volunteers with normal hearing participated in this experiment. The threshold-shifts by water injection in the ear canal were measured. AC, BC, and CC thresholds at 0.5–4 kHz were measured in the 0%-, 40%-, and 80%-water injection conditions. In addition, CC thresholds were also measured for the 20%-, 60%-, 100%-, and overflowing-water injection conditions. The contributions of the vibrations of the cartilaginous portion were evaluated by the threshold-shifts. For AC and BC, the threshold-shifts by the water injection were 22.6–53.3 dB and within 14.9 dB at the frequency of 0.5–4 kHz, respectively. For CC, when the water was filled within the bony portion, the thresholds were elevated to the same degree as AC. When the water was additionally injected to reach the cartilaginous portion, the thresholds at 0.5 and 1 kHz dramatically decreased by 27.4 and 27.5 dB, respectively. In addition, despite blocking AC by the injected water, the CC thresholds in force level were remarkably lower than those for BC. The vibration of the cartilaginous portion contributes to the sound transmission, particularly in the low frequency range. Although the airborne sound is radiated into the ear canal in both BC and CC, the mechanism underlying its generation is different between them. CC generates airborne sound in the canal more efficiently than BC. The current findings suggest that CC is not a hybrid of AC and BC. PMID:25768088

Effects of high intensity noise on the vestibular system in rats

PubMed Central

Stewart, Courtney; Yu, Yue; Huang, Jun; Maklad, Adel; Tang, Xuehui; Allison, Jerome; Mustain, William; Zhou, Wu; Zhu, Hong

2016-01-01

Some individuals with noise-induced hearing loss (NIHL) also report balance problems. These accompanying vestibular complaints are not well understood. The present study used a rat model to examine the effects of noise exposure on the vestibular system. Rats were exposed to continuous broadband white noise (0–24kHz) at an intensity of 116dB sound pressure level (SPL) via insert ear phones in one ear for three hours under isoflurane anesthesia. Seven days after the exposure, a significant increase in ABR threshold (43.3±1.9dB) was observed in the noise-exposed ears, indicating hearing loss. Effects of noise exposure on vestibular function were assessed by three approaches. First, fluorescein-conjugated phalloidin staining was used to assess vestibular stereocilia following noise exposure. This analysis revealed substantial sensory stereocilia bundle loss in the saccular and utricular maculae as well as in the anterior and horizontal semicircular canal cristae, but not in the posterior semicircular canal cristae. Second, single unit recording of vestibular afferent activity was performed under pentobarbital anesthesia. A total of 548 afferents were recorded from 10 noise-treated rats and 12 control rats. Noise exposure produced a moderate reduction in baseline firing rates of regular otolith afferents and anterior semicircular canal afferents. Also a moderate change was noted in the gain and phase of the horizontal and anterior semicircular canal afferent’s response to sinusoidal head rotation (1 and 2Hz, 45 degrees/s peak velocity). Third, noise exposure did not result in significant changes in gain or phase of the horizontal rotational and translational vestibular-ocular reflex (VOR). These results suggest that noise exposure not only causes hearing loss, but also causes substantial damage in the peripheral vestibular system in the absence of immediate clinically measurable vestibular signs. These peripheral deficits, however, may lead to vestibular disorders over time. PMID:26970474

The Effect of Superior Semicircular Canal Dehiscence on Intracochlear Sound Pressures

PubMed Central

Pisano, Dominic V.; Niesten, Marlien E.F.; Merchant, Saumil N.; Nakajima, Hideko Heidi

2013-01-01

Semicircular canal dehiscence (SCD) is a pathological opening in the bony wall of the inner ear that can result in conductive hearing loss. The hearing loss is variable across patients, and the precise mechanism and source of variability are not fully understood. Simultaneous measurements of basal intracochlear sound pressures in scala vestibuli (SV) and scala tympani (ST) enable quantification of the differential pressure across the cochlear partition, the stimulus that excites the cochlear partition. We used intracochlear sound pressure measurements in cadaveric preparations to study the effects of SCD size. Sound-induced pressures in SV and ST, as well as stapes velocity and ear-canal pressure were measured simultaneously for various sizes of SCD followed by SCD patching. Our results showed that at low frequencies (<600 Hz), SCD decreased the pressure in both SV and ST, as well as differential pressure, and these effects became more pronounced as dehiscence size was increased. Near 100 Hz, SV decreased about 10 dB for a 0.5 mm dehiscence and 20 dB for a 2 mm dehiscence, while ST decreased about 8 dB for a 0.5 mm dehiscence and 18 dB for a 2mm dehiscence. Differential pressure decreased about 10 dB for a 0.5 mm dehiscence and about 20 dB for a 2 mm dehiscense at 100 Hz. In some ears, for frequencies above 1 kHz, the smallest pinpoint dehiscence had bigger effects on the differential pressure (10 dB decrease) than larger dehiscenses (less than 10 dB decrease), suggesting larger hearing losses in this frequency range. These effects due to SCD were reversible by patching the dehiscence. We also showed that under certain circumstances such as SCD, stapes velocity is not related to how the ear can transduce sound across the cochlear partition because it is not directly related to the differential pressure, emphasizing that certain pathologies cannot be fully assessed by measurements such as stapes velocity. PMID:22814034

The deafness gene dfna5 is crucial for ugdh expression and HA production in the developing ear in zebrafish.

PubMed

Busch-Nentwich, Elisabeth; Söllner, Christian; Roehl, Henry; Nicolson, Teresa

2004-02-01

Over 30 genes responsible for human hereditary hearing loss have been identified during the last 10 years. The proteins encoded by these genes play roles in a diverse set of cellular functions ranging from transcriptional regulation to K(+) recycling. In a few cases, the genes are novel and do not give much insight into the cellular or molecular cause for the hearing loss. Among these poorly understood deafness genes is DFNA5. How the truncation of the encoded protein DFNA5 leads to an autosomal dominant form of hearing loss is not clear. In order to understand the biological role of Dfna5, we took a reversegenetic approach in zebrafish. Here we show that morpholino antisense nucleotide knock-down of dfna5 function in zebrafish leads to disorganization of the developing semicircular canals and reduction of pharyngeal cartilage. This phenotype closely resembles previously isolated zebrafish craniofacial mutants including the mutant jekyll. jekyll encodes Ugdh [uridine 5'-diphosphate (UDP)-glucose dehydrogenase], an enzyme that is crucial for production of the extracellular matrix component hyaluronic acid (HA). In dfna5 morphants, expression of ugdh is absent in the developing ear and pharyngeal arches, and HA levels are strongly reduced in the outgrowing protrusions of the developing semicircular canals. Previous studies suggest that HA is essential for differentiating cartilage and directed outgrowth of the epithelial protrusions in the developing ear. We hypothesize that the reduction of HA production leads to uncoordinated outgrowth of the canal columns and impaired facial cartilage differentiation.

The ear: Diagnostic imaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

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.

Vitamin D receptor deficiency impairs inner ear development in zebrafish.

PubMed

Kwon, Hye-Joo

2016-09-16

The biological actions of vitamin D are largely mediated through binding to the vitamin D receptor (VDR), a member of the nuclear hormone receptor family, which regulates gene expression in a wide variety of tissues and cells. Mutations in VDR gene have been implicated in ear disorders (hearing loss and balance disorder) but the mechanisms are not well established. In this study, to investigate the role of VDR in inner ear development, morpholino-mediated gene knockdown approaches were used in zebrafish model system. Two paralogs for VDR, vdra and vdrb, have been identified in zebrafish. Knockdown of vdra had no effect on ear development, whereas knockdown of vdrb displayed morphological ear defects including smaller otic vesicles with malformed semicircular canals and abnormal otoliths. Loss-of-vdrb resulted in down-regulation of pre-otic markers, pax8 and pax2a, indicating impairment of otic induction. Furthermore, zebrafish embryos lacking vdrb produced fewer sensory hair cells in the ears and showed disruption of balance and motor coordination. These data reveal that VDR signaling plays an important role in ear development. Copyright © 2016 Elsevier Inc. All rights reserved.

Perichondritis

MedlinePlus

... Ear piercing (especially piercing of the cartilage) Contact sports Trauma to the side of the head Ear ... external ear. In: Flint PW, Haughey BH, Lund V, et al, eds. Cummings Otolaryngology . 6th ed. Philadelphia, ...

Otologic manifestations of Fanconi anemia and other inherited bone marrow failure syndromes.

PubMed

Kalejaiye, Adedoyin; Giri, Neelam; Brewer, Carmen C; Zalewski, Christopher K; King, Kelly A; Adams, Charleen D; Rosenberg, Philip S; Kim, H Jeffrey; Alter, Blanche P

2016-12-01

The inherited bone marrow failure syndromes (IBMFSs) are diverse disorders with syndrome-specific features; their otologic and audiologic manifestations have not been well described. Our objective was to characterize these in patients with Fanconi anemia (FA), dyskeratosis congenita (DC), Diamond-Blackfan anemia (DBA), and Shwachman-Diamond syndrome (SDS), and to determine the association between physical findings and hearing loss. Patients with an IBMFS underwent comprehensive clinical and laboratory evaluations and testing for syndrome-specific gene mutations. Hearing loss was measured by pure tone audiometry and otologic abnormalities by otomicroscopy. Patients included 33 with FA, 37 with DC, 32 with DBA, and nine with SDS. Hearing loss was most frequent in patients with FA (45%) and DBA (14%). The most common type of hearing loss in FA was conductive (65%). Absent or hypoplastic radius, noted in 21% of the patients with FA, was associated with hearing loss in all cases. Otomicroscopy was abnormal in 66% of patients with FA. Characteristic ear abnormalities included small tympanic membrane (66%), malformed malleus (57%), aberrant tympanic bony island (48%), narrow external auditory canal (EAC) (32%), and abnormal course of chorda tympani (34%). Ear malformations were almost always associated with hearing loss. Hearing loss was rare in patients with DC and SDS. FA is the major IBMFS with associated hearing loss, which is most commonly conductive. Radial hypoplasia or aplasia and characteristic congenital ear malformations are associated with hearing loss in patients with FA. Recognition of these syndrome-specific abnormalities should lead to earlier management of hearing loss. © 2016 Wiley Periodicals, Inc.

Cochlear Implant Electrode Effect on Sound Energy Transfer within the Cochlea during Acoustic Stimulation

PubMed Central

Greene, Nathaniel T.; Mattingly, Jameson K.; Jenkins, Herman A.; Tollin, Daniel J.; Easter, James R.; Cass, Stephen P.

2015-01-01

Hypothesis Cochlear implants (CI) designed for hearing preservation will not alter mechanical properties of the middle and inner ear as measured by intracochlear pressure (PIC) and stapes velocity (Vstap). Background CIs designed to provide combined electrical and acoustic stimulation (EAS) are now available. To maintain functional acoustic hearing, it is important to know if a CI electrode can alter middle or inner ear mechanics, as any alteration could contribute to elevated low-frequency thresholds in EAS patients. Methods Seven human cadaveric temporal bones were prepared, and pure-tone stimuli from 120Hz–10kHz were presented at a range of intensities up to 110 dB SPL. PIC in the scala vestibuli (PSV) and tympani (PST) were measured with fiber-optic pressure sensors concurrently with VStap using laser Doppler vibrometry. Five CI electrodes from two different manufacturers, with varying dimensions were inserted via a round window approach at six different depths (16–25 mm). Results The responses of PIC and VStap to acoustic stimulation were assessed as a function of stimulus frequency, normalized to SPL in the external auditory canal (EAC), in baseline and electrode inserted conditions. Responses measured with electrodes inserted were generally within ~5 dB of baseline, indicating little effect of cochlear implant electrode insertion on PIC and VStap. Overall, mean differences across conditions were small for all responses, and no substantial differences were consistently visible across electrode types. Conclusions Results suggest that the influence of a CI electrode on middle and inner ear mechanics is minimal, despite variation in electrode lengths and configurations. PMID:26333018

Contralateral ear occlusion for improving the reliability of otoacoustic emission screening tests.

PubMed

Papsin, Emily; Harrison, Adrienne L; Carraro, Mattia; Harrison, Robert V

2014-01-01

Newborn hearing screening is an established healthcare standard in many countries and testing is feasible using otoacoustic emission (OAE) recording. It is well documented that OAEs can be suppressed by acoustic stimulation of the ear contralateral to the test ear. In clinical otoacoustic emission testing carried out in a sound attenuating booth, ambient noise levels are low such that the efferent system is not activated. However in newborn hearing screening, OAEs are often recorded in hospital or clinic environments, where ambient noise levels can be 60-70 dB SPL. Thus, results in the test ear can be influenced by ambient noise stimulating the opposite ear. Surprisingly, in hearing screening protocols there are no recommendations for avoiding contralateral suppression, that is, protecting the opposite ear from noise by blocking the ear canal. In the present study we have compared transient evoked and distortion product OAEs measured with and without contralateral ear plugging, in environmental settings with ambient noise levels <25 dB SPL, 45 dB SPL, and 55 dB SPL. We found out that without contralateral ear occlusion, ambient noise levels above 55 dB SPL can significantly attenuate OAE signals. We strongly suggest contralateral ear occlusion in OAE based hearing screening in noisy environments.

Nodular Fasciitis of External Auditory Canal

PubMed Central

Ahn, Jihyun; Kim, Sunyoung; Park, Youngsil

2016-01-01

Nodular fasciitis is a pseudosarcomatous reactive process composed of fibroblasts and myofibroblasts, and it is most common in the upper extremities. Nodular fasciitis of the external auditory canal is rare. To the best of our knowledge, less than 20 cases have been reported to date. We present a case of nodular fasciitis arising in the cartilaginous part of the external auditory canal. A 19-year-old man complained of an auricular mass with pruritus. Computed tomography showed a 1.7 cm sized soft tissue mass in the right external auditory canal, and total excision was performed. Histologic examination revealed spindle or stellate cells proliferation in a fascicular and storiform pattern. Lymphoid cells and erythrocytes were intermixed with tumor cells. The stroma was myxoid to hyalinized with a few microcysts. The tumor cells were immunoreactive for smooth muscle actin, but not for desmin, caldesmon, CD34, S-100, anaplastic lymphoma kinase, and cytokeratin. The patient has been doing well during the 1 year follow-up period. PMID:27304679

Comparison of Middle Ear Visualization With Endoscopy and Microscopy.

PubMed

Bennett, Marc L; Zhang, Dongqing; Labadie, Robert F; Noble, Jack H

2016-04-01

The primary goal of chronic ear surgery is the creation of a safe, clean dry ear. For cholesteatomas, complete removal of disease is dependent on visualization. Conventional microscopy is adequate for most dissection, but various subregions of the middle ear are better visualized with endoscopy. The purpose of the present study was to quantitatively assess the improved visualization that endoscopes afford as compared with operating microscopes. Microscopic and endoscopic views were simulated using a three-dimensional model developed from temporal bone scans. Surface renderings of the ear canal and middle ear subsegments were defined and the percentage of visualization of each middle ear subsegment, both with and without ossicles, was then determined for the microscope as well as for 0-, 30-, and 45-degree endoscopes. Using this information, we analyzed which mode of visualization is best suited for dissection within a particular anatomical region. Using a 0-degree scope provides significantly more visualization of every subregion, except the antrum, compared with a microscope. In addition, angled scopes permit visualizing significantly more surface area of every subregion of the middle ear than straight scopes or microscopes. Endoscopes offer advantages for cholesteatoma dissection in difficult-to-visualize areas including the sinus tympani and epitympanum.

The inner ear of Diacodexis, the oldest artiodactyl mammal

PubMed Central

Orliac, M J; Benoit, J; O'Leary, M A

2012-01-01

We provide the first detailed description of the inner ear of the oldest artiodactyl, Diacodexis, based on a three-dimensional reconstruction extracted from computed tomography imagery of a skull of Diacodexis ilicis of earliest Wasatchian age (ca. 55 Ma). This description provides new anatomical data for the earliest artiodactyls, and reveals that the bony labyrinth of Diacodexis differs greatly from that of modern artiodactyls described so far. The bony labyrinth of Diacodexis presents a weakly coiled cochlea (720 °), a secondary common crus, a dorsal extension of the anterior semicircular canal more pronounced than that of the posterior one, and a small angle between the basal turn of the bony cochlear canal and the lateral semicircular canal. This suite of characters also occurs in basal eutherian mammals. Diacodexis strongly resembles small living tragulid ruminants in its overall body shape and hindlimb proportions. Comparison of the bony labyrinth of Diacodexis to that of the tragulid Moschiola meminna (Indian mouse deer) reveals great morphological difference in cochlear shape and semicircular canal disposition. The shape of the cochlea suggests that Diacodexis was a high-frequency hearing specialist, with a high low-frequency hearing limit (543 Hz at 60 dB). By comparison, the estimated low-frequency limit of Moschiola meminna is much lower (186.0 Hz at 60 dB). We also assess the locomotor agility of Diacodexis based on measurements of the semicircular canals. Locomotor agility estimates for Diacodexis range between 3.62 and 3.93, and suggest a degree of agility compatible with a nimble, fast running to jumping animal. These results are congruent with the postcranial functional analysis for this extinct taxon. PMID:22938073

Transparent model of temporal bone and vestibulocochlear organ made by 3D printing.

PubMed

Suzuki, Ryoji; Taniguchi, Naoto; Uchida, Fujio; Ishizawa, Akimitsu; Kanatsu, Yoshinori; Zhou, Ming; Funakoshi, Kodai; Akashi, Hideo; Abe, Hiroshi

2018-01-01

The vestibulocochlear organ is composed of tiny complex structures embedded in the petrous part of the temporal bone. Landmarks on the temporal bone surface provide the only orientation guide for dissection, but these need to be removed during the course of dissection, making it difficult to grasp the underlying three-dimensional structures, especially for beginners during gross anatomy classes. We report herein an attempt to produce a transparent three-dimensional-printed model of the human ear. En bloc samples of the temporal bone from donated cadavers were subjected to computed tomography (CT) scanning, and on the basis of the data, the surface temporal bone was reconstructed with transparent resin and the vestibulocochlear organ with white resin to create a 1:1.5 scale model. The carotid canal was stuffed with red cotton, and the sigmoid sinus and internal jugular vein were filled with blue clay. In the inner ear, the internal acoustic meatus, cochlea, and semicircular canals were well reconstructed in detail with white resin. The three-dimensional relationships of the semicircular canals, spiral turns of the cochlea, and internal acoustic meatus were well recognizable from every direction through the transparent surface resin. The anterior semicircular canal was obvious immediately beneath the arcuate eminence, and the topographical relationships of the vestibulocochlear organ and adjacent great vessels were easily discernible. We consider that this transparent temporal bone model will be a very useful aid for better understanding of the gross anatomy of the vestibulocochlear organ.

Hyaluronan as a propellant for epithelial movement: the development of semicircular canals in the inner ear of Xenopus.

PubMed

Haddon, C M; Lewis, J H

1991-06-01

The membranous labyrinth of the inner ear, with its three semicircular canals, originates from a simple spheroidal otic vesicle. The process is easily observed in Xenopus. The vesicle develops three dorsal outpocketings; from the two opposite faces of each outpocketing pillars of tissue are protruded into the lumen; and these paired 'axial protrusions' eventually meet and fuse, to form a column of tissue spanning the lumen of the outpocketing like the hub of a wheel, with a tube of epithelium forming the semicircular canal around the periphery. Each axial protrusion consists of epithelium encasing a core of largely cell-free extracellular matrix that stains strongly with alcian blue. In sections, at least 60% of the stainable material is removed by treatment with Streptomyces hyaluronidase. When Streptomyces hyaluronidase is microinjected into the core of a protrusion in vivo, the protrusion collapses and the corresponding semicircular canal fails to form. Hyaluronan (hyaluronic acid) in the core of the protrusion therefore seems to be essential in driving the extension of the protrusion. Autoradiography with tritiated glucosamine indicates that the hyaluronan-rich matrix is synthesised by the epithelium covering the tip of the protrusion; the basal lamina here appears to be discontinuous. These findings indicate that the epithelium of the axial protrusion propels itself into the lumen of the otocyst by localised synthesis of hyaluronan. Hyaluronan may be used in a similar way in the development of other organs, such as the heart and the secondary palate.

Identifying Otosclerosis with Aural Acoustical Tests of Absorbance, Group Delay, Acoustic Reflex Threshold, and Otoacoustic Emissions.

PubMed

Keefe, Douglas H; Archer, Kelly L; Schmid, Kendra K; Fitzpatrick, Denis F; Feeney, M Patrick; Hunter, Lisa L

2017-10-01

Otosclerosis is a progressive middle-ear disease that affects conductive transmission through the middle ear. Ear-canal acoustic tests may be useful in the diagnosis of conductive disorders. This study addressed the degree to which results from a battery of ear-canal tests, which include wideband reflectance, acoustic stapedius muscle reflex threshold (ASRT), and transient evoked otoacoustic emissions (TEOAEs), were effective in quantifying a risk of otosclerosis and in evaluating middle-ear function in ears after surgical intervention for otosclerosis. To evaluate the ability of the test battery to classify ears as normal or otosclerotic, measure the accuracy of reflectance in classifying ears as normal or otosclerotic, and evaluate the similarity of responses in normal ears compared with ears after surgical intervention for otosclerosis. A quasi-experimental cross-sectional study incorporating case control was used. Three groups were studied: one diagnosed with otosclerosis before corrective surgery, a group that received corrective surgery for otosclerosis, and a control group. The test groups included 23 ears (13 right and 10 left) with normal hearing from 16 participants (4 male and 12 female), 12 ears (7 right and 5 left) diagnosed with otosclerosis from 9 participants (3 male and 6 female), and 13 ears (4 right and 9 left) after surgical intervention from 10 participants (2 male and 8 female). Participants received audiometric evaluations and clinical immittance testing. Experimental tests performed included ASRT tests with wideband reference signal (0.25-8 kHz), reflectance tests (0.25-8 kHz), which were parameterized by absorbance and group delay at ambient pressure and at swept tympanometric pressures, and TEOAE tests using chirp stimuli (1-8 kHz). ASRTs were measured in ipsilateral and contralateral conditions using tonal and broadband noise activators. Experimental ASRT tests were based on the difference in wideband-absorbed sound power before and after presenting the activator. Diagnostic accuracy to classify ears as otosclerotic or normal was quantified by the area under the receiver operating characteristic curve (AUC) for univariate and multivariate reflectance tests. The multivariate predictor used a small number of input reflectance variables, each having a large AUC, in a principal components analysis to create independent variables and followed by a logistic regression procedure to classify the test ears. Relative to the results in normal ears, diagnosed otosclerosis ears more frequently showed absent TEOAEs and ASRTs, reduced ambient absorbance at 4 kHz, and a different pattern of tympanometric absorbance and group delay (absorbance increased at 2.8 kHz at the positive-pressure tail and decreased at 0.7-1 kHz at the peak pressure, whereas group delay decreased at positive and negative-pressure tails from 0.35-0.7 kHz, and at 2.8-4 kHz at positive-pressure tail). Using a multivariate predictor with three reflectance variables, tympanometric reflectance (AUC = 0.95) was more accurate than ambient reflectance (AUC = 0.88) in classifying ears as normal or otosclerotic. Reflectance provides a middle-ear test that is sensitive to classifying ears as otosclerotic or normal, which may be useful in clinical applications. American Academy of Audiology

Use of a highly transparent zebrafish mutant for investigations in the development of the vertebrate auditory system (Conference Presentation)

NASA Astrophysics Data System (ADS)

Wisniowiecki, Anna M.; Mattison, Scott P.; Kim, Sangmin; Riley, Bruce; Applegate, Brian E.

2016-03-01

Zebrafish, an auditory specialist among fish, offer analogous auditory structures to vertebrates and is a model for hearing and deafness in vertebrates, including humans. Nevertheless, many questions remain on the basic mechanics of the auditory pathway. Phase-sensitive Optical Coherence Tomography has been proven as valuable technique for functional vibrometric measurements in the murine ear. Such measurements are key to building a complete understanding of auditory mechanics. The application of such techniques in the zebrafish is impeded by the high level of pigmentation, which develops superior to the transverse plane and envelops the auditory system superficially. A zebrafish double mutant for nacre and roy (mitfa-/- ;roya-/- [casper]), which exhibits defects for neural-crest derived melanocytes and iridophores, at all stages of development, is pursued to improve image quality and sensitivity for functional imaging. So far our investigations with the casper mutants have enabled the identification of the specialized hearing organs, fluid-filled canal connecting the ears, and sub-structures of the semicircular canals. In our previous work with wild-type zebrafish, we were only able to identify and observe stimulated vibration of the largest structures, specifically the anterior swim bladder and tripus ossicle, even among small, larval specimen, with fully developed inner ears. In conclusion, this genetic mutant will enable the study of the dynamics of the zebrafish ear from the early larval stages all the way into adulthood.

Perilymph pharmacokinetics of markers and dexamethasone applied and sampled at the lateral semi-circular canal.

PubMed

Salt, Alec N; Hartsock, Jared J; Gill, Ruth M; Piu, Fabrice; Plontke, Stefan K

2012-12-01

Perilymph pharmacokinetics was investigated by a novel approach, in which solutions containing drug or marker were injected from a pipette sealed into the perilymphatic space of the lateral semi-circular canal (LSCC). The cochlear aqueduct provides the outlet for fluid flow so this procedure allows almost the entire perilymph to be exchanged. After wait times of up to 4 h the injection pipette was removed and multiple, sequential samples of perilymph were collected from the LSCC. Fluid efflux at this site results from cerebrospinal fluid (CSF) entry into the basal turn of scala tympani (ST) so the samples allow drug levels from different locations in the ear to be defined. This method allows the rate of elimination of substances from the inner ear to be determined more reliably than with other delivery methods in which drug may only be applied to part of the ear. Results were compared for the markers trimethylphenylammonium (TMPA) and fluorescein and for the drug dexamethasone (Dex). For each substance, the concentration in fluid samples showed a progressive decrease as the delay time between injection and sampling was increased. This is consistent with the elimination of substance from the ear with time. The decline with time was slowest for fluorescein, was fastest for Dex, with TMPA at an intermediate rate. Simulations of the experiments showed that elimination occurred more rapidly from scala tympani (ST) than from scala vestibuli (SV). Calculated elimination half-times from ST averaged 54.1, 24.5 and 22.5 min for fluorescein, TMPA and Dex respectively and from SV 1730, 229 and 111 min respectively. The elimination of Dex from ST occurred considerably faster than previously appreciated. These pharmacokinetic parameters provide an important foundation for understanding of drug treatments of the inner ear.

Functional Implications of Ubiquitous Semicircular Canal Non-Orthogonality in Mammals

PubMed Central

Berlin, Jeri C.; Kirk, E. Christopher; Rowe, Timothy B.

2013-01-01

The ‘canonical model’ of semicircular canal orientation in mammals assumes that 1) the three ipsilateral canals of an inner ear exist in orthogonal planes (i.e., orthogonality), 2) corresponding left and right canal pairs have equivalent angles (i.e., angle symmetry), and 3) contralateral synergistic canals occupy parallel planes (i.e., coplanarity). However, descriptions of vestibular anatomy that quantify semicircular canal orientation in single species often diverge substantially from this model. Data for primates further suggest that semicircular canal orthogonality varies predictably with the angular head velocities encountered in locomotion. These observations raise the possibility that orthogonality, symmetry, and coplanarity are misleading descriptors of semicircular canal orientation in mammals, and that deviations from these norms could have significant functional consequences. Here we critically assess the canonical model of semicircular canal orientation using high-resolution X-ray computed tomography scans of 39 mammal species. We find that substantial deviations from orthogonality, angle symmetry, and coplanarity are the rule for the mammals in our comparative sample. Furthermore, the degree to which the semicircular canals of a given species deviate from orthogonality is negatively correlated with estimated vestibular sensitivity. We conclude that the available comparative morphometric data do not support the canonical model and that its overemphasis as a heuristic generalization obscures a large amount of functionally relevant variation in semicircular canal orientation between species. PMID:24260256

Swimmer's Ear (External Otitis)

MedlinePlus

... t help, your doctor might prescribe a stronger pain reliever. You'll use this only for a short time — until the ear drops and antibiotics begin to work. To protect your ear while it heals, your ...

Active middle ear implant after lateral petrosectomy and radiotherapy for ear cancer.

PubMed

Cristalli, Giovanni; Sprinzl, Georg M; Wolf-Magele, Astrid; Marchesi, Paolo; Mercante, Giuseppe; Spriano, Giuseppe

2014-04-01

Tumor of the temporal bone is a rare disease with a very poor prognosis. Surgery and postoperative radiotherapy are usually the recommended treatments for squamous cell carcinoma (SCC) of the external and middle ear, which may cause conductive hearing loss. The purpose of this study was to evaluate the audiologic results and compliance of active middle ear implant (AMEI) and establish the feasibility of the procedure in a patient treated for middle ear cancer. A 73-year-old patient treated with lateral petrosectomy, neck dissection, reconstruction/obliteration by pedicled pectoralis major myocutaneous flap, and postoperative full dose radiotherapy for external and middle ear SCC was selected for AMEI. Preoperative audiometric and speech audiometry tests were performed on both ears before and after the activation. Pure tone free field audiometry. Binaural free field speech audiogram. Aided pure tone free field audiometry AMEI results show an increase in air conduction. Speech audiogram showed better discrimination scores in AMEI-aided situations. No complications were observed. AMEI after surgery followed by radiotherapy for middle ear cancer is feasible. Acoustic results in obliterated ear are satisfactory.

The effects of experimentally induced conductive hearing loss on spectral and temporal aspects of sound transmission through the ear.

PubMed

Eric Lupo, J; Koka, Kanthaiah; Thornton, Jennifer L; Tollin, Daniel J

2011-02-01

Conductive hearing loss (CHL) is known to produce hearing deficits, including deficits in sound localization ability. The differences in sound intensities and timing experienced between the two tympanic membranes are important cues to sound localization (ILD and ITD, respectively). Although much is known about the effect of CHL on hearing levels, little investigation has been conducted into the actual impact of CHL on sound location cues. This study investigated effects of CHL induced by earplugs on cochlear microphonic (CM) amplitude and timing and their corresponding effect on the ILD and ITD location cues. Acoustic and CM measurements were made in 5 chinchillas before and after earplug insertion, and again after earplug removal using pure tones (500 Hz to 24 kHz). ILDs in the unoccluded condition demonstrated position and frequency dependence where peak far-lateral ILDs approached 30 dB for high frequencies. Unoccluded ear ITD cues demonstrated positional and frequency dependence with increased ITD cue for both decreasing frequency (±420 μs at 500 Hz, ±310 μs for 1-4 kHz) and increasingly lateral sound source locations. Occlusion of the ear canal with foam plugs resulted in a mild, frequency-dependent conductive hearing loss of 10-38 dB (mean 31 ± 3.9 dB) leading to a concomitant frequency dependent increase in ILDs at all source locations. The effective ITDs increased in a frequency dependent manner with ear occlusion as a direct result of the acoustic properties of the plugging material, the latter confirmed via acoustical measurements using a model ear canal with varying volumes of acoustic foam. Upon ear plugging with acoustic foam, a mild CHL is induced. Furthermore, the CHL induced by acoustic foam results in substantial changes in the magnitudes of both the ITD and ILD cues to sound location. Copyright © 2010 Elsevier B.V. All rights reserved.

The effects of experimentally induced conductive hearing loss on spectral and temporal aspects of sound transmission through the ear

PubMed Central

Lupo, J. Eric; Koka, Kanthaiah; Thornton, Jennifer L.; Tollin, Daniel J.

2010-01-01

Conductive hearing loss (CHL) is known to produce hearing deficits, including deficits in sound localization ability. The differences in sound intensities and timing experienced between the two tympanic membranes are important cues to sound localization (ILD and ITD, respectively). Although much is known about the effect of CHL on hearing levels, little investigation has been conducted into the actual impact of CHL on sound location cues. This study investigated effects of CHL induced by earplugs on cochlear microphonic (CM) amplitude and timing and their corresponding effect on the ILD and ITD location cues. Acoustic and CM measurements were made in 5 chinchillas before and after earplug insertion, and again after earplug removal using pure tones (500 Hz to 24 kHz). ILDs in the unoccluded condition demonstrated position and frequency dependence where peak far-lateral ILDs approached 30 dB for high frequencies. Unoccluded ear ITD cues demonstrated positional and frequency dependence with increased ITD cue for both decreasing frequency (± 420 µs at 500 Hz, ± 310 µs for 1–4 kHz ) and increasingly lateral sound source locations. Occlusion of the ear canal with foam plugs resulted in a mild, frequency-dependent conductive hearing loss of 10–38 dB (mean 31 ± 3.9 dB) leading to a concomitant frequency dependent increase in ILDs at all source locations. The effective ITDs increased in a frequency dependent manner with ear occlusion as a direct result of the acoustic properties of the plugging material, the latter confirmed via acoustical measurements using a model ear canal with varying volumes of acoustic foam. Upon ear plugging with acoustic foam, a mild CHL is induced. Furthermore, the CHL induced by acoustic foam results in substantial changes in the magnitudes of both the ITD and ILD cues to sound location. PMID:21073935

Effects of Stimulus Intensity on Low-Frequency Toneburst Cochlear Microphonic Waveforms.

PubMed

Zhang, Ming

2013-01-02

This study investigates changes in amplitude and delays in low-frequency toneburst cochlear microphonic (CM) waveforms recorded at the ear canal in response to different stimulus intensities. Ten volunteers aged 20-30 were recruited. Low-frequency CM waveforms at 500 Hz in response to a 14-ms toneburst were recorded from an ear canal electrode using electrocochleography techniques. The data was statistically analyzed in order to confirm whether the differences were significant in the effects of stimulus intensity on the amplitudes and delays of the low-frequency CM waveforms. Electromagnetic interference artifacts can jeopardize CM measurements but such artifacts can be avoided. The CM waveforms can be recorded at the ear canal in response to a toneburst which is longer than that used in ABR measurements. The CM waveforms thus recorded are robust, and the amplitude of CM waveforms is intensity-dependent. In contrast, the delay of CM waveforms is intensity-independent, which is different from neural responses as their delay or latency is intensity-dependent. These findings may be useful for development of the application of CM measurement as a supplementary approach to otoacoustic emission (OAE) measurement in the clinic which is severely affected by background acoustic noise. The development of the application in the assessment of low-frequency cochlear function may become possible if a further series of studies can verify the feasibility, but it is not meant to be a substitute for audiometry or OAE measurements. The measurement of detection threshold of CM waveform responses using growth function approach may become possible in the clinic. The intensity-independent nature of CMs with regards to delay measurements may also become an impacting factor for differential diagnoses and for designing new research studies.

Auditory brainstem evoked responses and temperature monitoring during pediatric cardiopulmonary bypass.

PubMed

Rodriguez, R A; Edmonds, H L; Auden, S M; Austin, E H

1999-09-01

To examine the effects of temperature on auditory brainstem responses (ABRs) in infants during hypothermic cardiopulmonary bypass for total circulatory arrest (TCA). The relationship between ABRs (as a surrogate measure of core-brain temperature) and body temperature as measured at several temperature monitoring sites was determined. In a prospective, observational study, ABRs were recorded non-invasively at normothermia and at every 1 or 2 degrees C change in ear-canal temperature during cooling and rewarming in 15 infants (ages: 2 days to 14 months) that required TCA. The ABR latencies and amplitudes and the lowest temperatures at which an ABR was identified (the threshold) were measured during both cooling and rewarming. Temperatures from four standard temperature monitoring sites were simultaneously recorded. The latencies of ABRs increased and amplitudes decreased with cooling (P < 0.01), but rewarming reversed these effects. The ABR threshold temperature as related to each monitoring site (ear-canal, nasopharynx, esophagus and bladder) was respectively determined as 23 +/- 2.2 degrees C, 20.8 +/- 1.7 degrees C, 14.6 +/- 3.4 degrees C, and 21.5 +/- 3.8 degrees C during cooling and 21.8 +/- 1.6 degrees C, 22.4 +/- 2.0 degrees C, 27.6 +/- 3.6 degrees C, and 23.0 +/- 2.4 degrees C during rewarming. The rewarming latencies were shorter and Q10 latencies smaller than the corresponding cooling values (P < 0.01). Esophageal and bladder sites were more susceptible to temperature variations as compared with the ear-canal and nasopharynx. No temperature site reliably predicted an electrophysiological threshold. A faster latency recovery during rewarming suggests that body temperature monitoring underestimates the effects of rewarming in the core-brain. ABRs may be helpful to monitor the effects of cooling and rewarming on the core-brain during pediatric cardiopulmonary bypass.

Effective masking levels for 500 and 2000 Hz bone conduction auditory steady state responses in infants and adults with normal hearing.

PubMed

Small, Susan A; Smyth, Aisling; Leon, Griselle

2014-01-01

Few studies have investigated effective masking levels (EMLs) needed to isolate the test ear for bone conduction assessments in infants. The objective of this study was to determine EMLs for 500 and 2000 Hz bone conduction auditory steady state responses (ASSRs) to amplitude (AM)/frequency-modulated (FM) stimuli for infants and adults with normal hearing. Maturational factors that contribute to infant-adult differences in EMLs will also be investigated. The present study and previously published 1000 and 4000 Hz EML data will be compared to investigate EML across four frequencies. These findings will provide a starting point for implementing clinical masking for infant bone conduction testing using physiological measures. Participants were 15 infants (7 to 35 weeks) and 15 adults (21 to 56 years) with normal hearing. Bone-conducted single ASSR stimuli (research MASTER) were 100% AM and 25% FM at 85 and 101 Hz for 500 and 2000 Hz carrier frequencies, respectively. They were presented at 25 and 35 dB HL for 500 Hz and at 35 and 45 dB HL for 2000 Hz for both infants and adults (approximately 10 and 20 dB SL at each frequency for infants). Air-conducted narrowband maskers were presented to both ears simultaneously. Real-ear to coupler differences were measured to account for differences in the sound pressure developed in infant and adult ear canals as a result of ear-canal size. Data analyses were conducted for mean EMLs across frequency (500 to 4000 Hz) and between age groups. Masked and unmasked ASSR amplitudes were compared for 500 and 2000 Hz. Both infants and adults required much more masking (25 to 33 dB) to eliminate responses at 500 compared with 2000 Hz. On average, infants required 16 dB more masking at 500 Hz and similar amounts of masking at 2000 Hz compared with adults. When adjusted for ear-canal size and bone conduction sensitivity, the pattern of results did not change. Across all four frequencies, infants showed a systematic decrease in mean EMLs with an increase in frequency; all pair-wise comparisons were significant except 2000 versus 4000 Hz. Adults showed smaller frequency-dependent changes in EML (only significantly greater for 500 versus 2000 Hz and 4000 Hz). When ear-canal size and bone conduction sensitivity were taken into account, only 500 Hz required more masking than other frequencies in infants; there were no significant frequency-dependent trends for adults, although the greater EMLs at 1000 versus 2000 Hz and 4000 Hz approached significance. Unmasked and masked amplitudes tended to be larger for 2000 Hz but not for 500 Hz when comparing infants with adults. EMLs appropriate for infants for bone conduction ASSRs elicited to AM/FM stimuli are considerably higher at 500 compared with 2000 Hz. Infants also need more masking at 500 Hz compared with adults but the same amount of masking at 2000 Hz. Comparisons across four frequencies reveal a systematic decrease in EML with an increase in frequency in infants, which is not apparent in adults. Recommended EMLs for AM/FM bone-conducted ASSR stimuli presented at 35 dB HL for 500, 1000, 2000, and 4000 Hz, respectively, are: (1) infants: 81, 68, 59, and 45 dB SPL, and (2) adults: 66, 63, 59, and 55 dB SPL.

Relation of motion sickness susceptibility to vestibular and behavioral measures of orientation

NASA Technical Reports Server (NTRS)

Peterka, Robert J.

1995-01-01

The objective is to determine the relationship of motion sickness susceptibility to vestibulo-ocular reflexes (VOR), motion perception, and behavioral utilization of sensory orientation cues for the control of postural equilibrium. The work is focused on reflexes and motion perception associated with pitch and roll movements that stimulate the vertical semicircular canals and otolith organs of the inner ear. This work is relevant to the space motion sickness problem since 0 g related sensory conflicts between vertical canal and otolith motion cues are a likely cause of space motion sickness.

An assessment of a conical horn waveguide to represent the human eardrum

NASA Astrophysics Data System (ADS)

Fields, Taylor N.; Schnetzer, Lucia; Brister, Eileen; Yates, Charles W.; Withnell, Robert H.

2018-05-01

This study examined a model of the acoustic input impedance of the ear that includes a waveguide model of the eardrum. The eardrum was modeled as a lossless conical-horn with rigid walls. The ear canal was modeled as a one-dimensional lossy transmission line. The output impedance of the eardrum, the middle ear, and the cochlea, was modeled as a circuit analog. The model was fit to acoustic input impedance data from human ears using a nonlinear least-squares fit. The impact of a conical-horn shape for the eardrum was quantified by comparison with the eardrum modeled as a near-flat surface. The model provided a good match to the data over the frequency range examined. A conical-horn model of the human eardrum provided gain at high frequencies, most notably above 1–2 kHz, with a broader middle-ear frequency response. This finding may suggest that eardrum shape plays an important role in sound transmission to the cochlea.

[A study of otitis externa associated with Malassezia].

PubMed

Shiota, Ryoko; Kaneko, Takamasa; Yano, Hiroaki; Takeshita, Kimiko; Nishioka, Keiko; Makimura, Koichi

2009-01-01

Malassezia-positive smears can be recognized from otitis externa, however, there are few references in the literature to the relation between Malassezia and otitis externa. Therefore, the bacterial and clinical characteristics of 72 cases (63 patients) with otitis externa were investigated at the Department of Otorhinolaryngology, Takinomiya General Hospital to analyze this. Thirty-seven cases were bacterial otitis externa, 20 cases were fungal otitis externa, and 15 cases were etiological agents unknown in this study. The causative organisms in fungal otitis externa were the genera Aspergillus (10 cases), Malassezia (5) and Candida (5), respectively. We suspected that 5 cases were caused by Malassezia because Malassezia cell counts were greater than 10 per field (x 400), and a large number of Malassezia were isolated from all cases. In these cases, many squamous epithelial cells were observed by direct examination, and cells from the middle or basal layer of the ear canal were also recognized in three cases. Therefore, accelerated turnover of epidermal cells of the ear canal was suggested. The main symptoms were itching and fullness in the ear, with observations of redness and erosion in objective deterioration, and we felt that these conditions were similar to seborrheic dermatitis (SD). In addition, these five cases were confirmed as fungus-related otitis externa by their improvement with antifungal agents.

Distribution of standing-wave errors in real-ear sound-level measurements.

PubMed

Richmond, Susan A; Kopun, Judy G; Neely, Stephen T; Tan, Hongyang; Gorga, Michael P

2011-05-01

Standing waves can cause measurement errors when sound-pressure level (SPL) measurements are performed in a closed ear canal, e.g., during probe-microphone system calibration for distortion-product otoacoustic emission (DPOAE) testing. Alternative calibration methods, such as forward-pressure level (FPL), minimize the influence of standing waves by calculating the forward-going sound waves separate from the reflections that cause errors. Previous research compared test performance (Burke et al., 2010) and threshold prediction (Rogers et al., 2010) using SPL and multiple FPL calibration conditions, and surprisingly found no significant improvements when using FPL relative to SPL, except at 8 kHz. The present study examined the calibration data collected by Burke et al. and Rogers et al. from 155 human subjects in order to describe the frequency location and magnitude of standing-wave pressure minima to see if these errors might explain trends in test performance. Results indicate that while individual results varied widely, pressure variability was larger around 4 kHz and smaller at 8 kHz, consistent with the dimensions of the adult ear canal. The present data suggest that standing-wave errors are not responsible for the historically poor (8 kHz) or good (4 kHz) performance of DPOAE measures at specific test frequencies.

Size Variation under Domestication: Conservatism in the inner ear shape of wolves, dogs and dingoes.

PubMed

Schweizer, Anita V; Lebrun, Renaud; Wilson, Laura A B; Costeur, Loïc; Schmelzle, Thomas; Sánchez-Villagra, Marcelo R

2017-10-17

A broad sample of wolves, dingoes, and domesticated dogs of different kinds and time periods was used to identify changes in size and shape of the organs of balance and hearing related to domestication and to evaluate the potential utility of uncovered patterns as markers of domestication. Using geometric morphometrics coupled with non-invasive imaging and three-dimensional reconstructions, we exposed and compared complex structures that remain largely conserved. There is no statistically significant difference in the levels of shape variation between prehistoric and modern dogs. Shape variance is slightly higher for the different components of the inner ear in modern dogs than in wolves, but these differences are not significant. Wolves express a significantly greater level of variance in the angle between the lateral and the posterior canal than domestic dog breeds. Wolves have smaller levels of size variation than dogs. In terms of the shape of the semicircular canals, dingoes reflect the mean shape in the context of variation in the sample. This mirrors the condition of feral forms in other organs, in which there is an incomplete return to the characteristics of the ancestor. In general, morphological diversity or disparity in the inner ear is generated by scaling.

The effect of round window reinforcement on human hearing

NASA Astrophysics Data System (ADS)

Guan, Xiying; Cheng, Y. Song; Galaiya, Deepa; Nakajima, Hideko H.

2018-05-01

The compliant round window (RW) allows volume velocity to flow within the incompressible fluid of the cochlea as the oval window vibrates during sound stimulation. Recently, surgically stiffened RW is emerging as a treatment for various conditions such as superior canal dehiscence and hyperacusis. However, we lack the basic understanding of how reinforcing the RW affects sound transmission in the ear. The aim of this study is to clarify the effect of RW reinforcement on hearing. To study the effect of RW reinforcement with tissue and adhesive, we measured intracochlear pressures in scala vestibuli (Psv) and scala tympani (Pst) at the cochlear base together with stapes velocity in response to sound at the ear canal. The cochlear input drive (Pdiff = Psv - Pst, an estimate of hearing) was determined before and after RW reinforcement in a fresh human cadaveric ear. Results show that increasing the RW stiffness by reinforcement can affect the cochlear input drive in unexpected ways. Below 200 Hz, RW reinforcement resulted in reduced stapes motion, however an increase in cochlear drive, consistent with increase in hearing. At 200-1000 Hz, the hearing and stapes motion both were slightly decreased. Reinforcing the RW had no effect above 1 kHz. To understand the cochlear mechanical effects of RW reinforcement, we used a lumped-element model that simulated our findings.

Basilar-membrane interference patterns from multiple internal reflection of cochlear traveling waves.

PubMed

Shera, Christopher A; Cooper, Nigel P

2013-04-01

At low stimulus levels, basilar-membrane (BM) mechanical transfer functions in sensitive cochleae manifest a quasiperiodic rippling pattern in both amplitude and phase. Analysis of the responses of active cochlear models suggests that the rippling is a mechanical interference pattern created by multiple internal reflection within the cochlea. In models, the interference arises when reverse-traveling waves responsible for stimulus-frequency otoacoustic emissions (SFOAEs) reflect off the stapes on their way to the ear canal, launching a secondary forward-traveling wave that combines with the primary wave produced by the stimulus. Frequency-dependent phase differences between the two waves then create the rippling pattern measurable on the BM. Measurements of BM ripples and SFOAEs in individual chinchilla ears demonstrate that the ripples are strongly correlated with the acoustic interference pattern measured in ear-canal pressure, consistent with a common origin involving the generation of SFOAEs. In BM responses to clicks, the ripples appear as temporal fine structure in the response envelope (multiple lobes, waxing and waning). Analysis of the ripple spacing and response phase gradients provides a test for the role of fast- and slow-wave modes of reverse energy propagation within the cochlea. The data indicate that SFOAE delays are consistent with reverse slow-wave propagation but much too long to be explained by fast waves.

Traumatic neuroma: a late complication of otoplasty.

PubMed

Lwin, Christine T-T; Birch, Jeremy; Giele, Henk

2007-01-01

We report on the development of traumatic ear lobe neuromas as a late complication of bilateral otoplasty performed 16 years previously. To our knowledge, this is the first and only described case of traumatic neuromas arising as a late complication of otoplasty in the English literature. Traumatic neuroma should be considered in the differential diagnosis of any nodular lesions that develop within the external ear in patients who have had otoplasty or any other form of external ear surgery or trauma.

Experimental studies on the acoustic properties of mastoid cavities.

PubMed

Tolley, N S; Ison, K; Mirza, A

1992-07-01

This study investigated the effects of open-mastoid surgery upon ear canal resonance. In particular an attempt was made to alter resonant properties by obliterating each cavity with silastic foam. The results from this study showed that open-mastoid surgery significantly decreased resonant frequency without producing an effect upon either the peak amplitude or the quality of the resonant peak as defined by the Q-factor. Restoring the natural resonance properties of an operated ear, if indicated, is likely to be a difficult objective to achieve in surgical terms.

Semicircular Canal Size and Locomotion in Colobine Monkeys: A Cautionary Tale.

PubMed

Rae, Todd C; Johnson, Paul Martin; Yano, Wataru; Hirasaki, Eishi

2016-01-01

The semicircular canals of the inner ear constitute the organ of balance, tracking head rotation during movement and facilitating stabilisation of vision. Morphological characteristics of the canals are correlated with agility scores related to locomotion. To date, however, the relationship between canal morphology and specific locomotor behaviours, such as leaping, is unclear. Knowledge of such a relationship could strengthen the inferences of locomotion of extinct taxa. To test this, crania of two sets of closely related primate species (Presbytis melalophos and P. potenziani; Colobus guereza and C. polykomos) that differ in the percentage of leaping in their locomotor repertoire were examined using microscopic computed tomography. Three-dimensional virtual models of the bony labyrinth were derived, and the radius of curvature of each of the three canals was evaluated relative to cranial size. The findings are contradictory; one leaping form (P. melalophos) differs from its congener in possessing significantly larger lateral canals, a pattern seen in previous studies of primates, while the other leaper (C. guereza) has significantly smaller posterior canals than its close relative. These results undermine efforts to determine specific locomotor behaviours from the bony labyrinth of extinct primates. © 2016 S. Karger AG, Basel.

Astronaut Walter Schirra gets modified calonic test

NASA Image and Video Library

1962-01-01

S62-06157 (1962) --- Astronaut Walter Schirra Jr. gets modified calonic test. His balance mechanism (semicircular canals) are tested by running cool water into ear and measuring effect on eye motions (nystagmus) after his six-orbit flight in the Sigma 7 spacecraft. Photo credit: NASA

Evaluation of the Repeatability and Accuracy of the Wideband Real-Ear-to-Coupler Difference.

PubMed

Vaisberg, Jonathan M; Folkeard, Paula; Pumford, John; Narten, Philipp; Scollie, Susan

2018-06-01

The real-ear-to-coupler difference (RECD) is an ANSI standardized method for estimating ear canal sound pressure level (SPL) thresholds and assisting in the prediction of real-ear aided responses. It measures the difference in dB between the SPL produced in the ear canal and the SPL produced in an HA-1 2-cc coupler by the same sound source. Recent evidence demonstrates that extended high-frequency bandwidth, beyond the hearing aid bandwidth typically measured, is capable of providing additional clinical benefit. The industry has, in turn, moved toward developing hearing aids and verification equipment capable of producing and measuring extended high-frequency audible output. As a result, a revised RECD procedure conducted using a smaller, 0.4-cc coupler, known as the wideband-RECD (wRECD), has been introduced to facilitate extended high-frequency coupler-based measurements up to 12.5 kHz. This study aimed to (1) compare test-retest repeatability between the RECD and wRECD and (2) measure absolute agreement between the RECD and wRECD when both are referenced to a common coupler. RECDs and wRECDs were measured bilaterally in adult ears by calculating the dB difference in SPL between the ear canal and coupler responses. Real-ear probe microphone measures were completed twice per ear per participant for both foam-tip and customized earmold couplings using the Audioscan Verifit 1 and Verifit 2 fitting systems, followed by measurements in the respective couplers. Twenty-one adults (mean age = 67 yr, range = 19-78) with typical aural anatomy (as determined by measures of impedance and otoscopy) participated in this study, leading to a sample size of 42 ears. Repeatability within RECD and wRECD was assessed for each coupling configuration using a repeated-measures analysis of variance (ANOVA) with test-retest and frequency as within-participants factors. Repeatability between the RECD and wRECD was assessed within each configuration using a repeated-measures ANOVA with test-retest, frequency, and coupler type as within-participants factors. Agreement between the RECD and wRECD was assessed for each coupling configuration using a repeated-measures ANOVA with RECD value, coupler type, and frequency as within-participants factors. Post hoc comparisons with Bonferroni corrections were used when appropriate to locate the frequencies at which differences occurred. A 3-dB criterion was defined to locate differences of clinical significance. Average absolute test-retest differences were within ±3 dB within each coupler and coupling configuration, and between the RECD and wRECD. The RECD and wRECD were in absolute agreement following HA-1-referenced transforms, with most frequencies agreeing within ±1 dB, except at 0.2 kHz for the earmold, and 0.2-0.25 kHz for the foam tip, where the average RECD exceeded the average wRECD by slightly >3 dB. Test-retest repeatability of the RECD (up to 8 kHz) and wRECD (up to 12.5 kHz) is acceptable and similar to previously reported data. The RECD and wRECD are referenced to different couplers, but can be rendered comparable with a simple transform, producing values that are in accordance with the ANSI S3.46-2013 standard. American Academy of Audiology.

Restudy of malformations of the internal auditory meatus, cochlear nerve canal and cochlear nerve.

PubMed

Li, Youjin; Yang, Jun; Liu, Jinfen; Wu, Hao

2015-07-01

The present study aims to restudy the correlation between the internal auditory meatus (IAM), the cochlear nerve canal (CNC), the cochlear nerve (CN) and inner ear malformations. In this retrospective study design, the abnormal diameter of the IAM, CNC and CN in patients with any kind of inner ear malformations was evaluated using multi-slice spiral computed tomography (MSCT) (37 patients) and magnetic resonance imaging (MRI) (18 patients). Of 37 MSCT-diagnosed patients, 2 had IAM atresia, 11 IAM stenosis, 22 enlarged IAM, and 2 normal IAM with an abnormal CN. MRI diagnoses of 18 patients revealed 8 cases of aplastic CN, 6 hypoplastic CN, and 4 normal CN. CNC stenosis was associated with CN hypoplasia (P < 0.001). Patients with absent or stenotic IAM had less CN development than those with normal or enlarged IAM (P = 0.001). We propose a modification of the existing classification systems with a view to distinguishing malformations of the IAM, CNC and CN.

The personal and scientific feud between Ernst Brücke and Josef Hyrtl.

PubMed

Wiest, Gerald; Baloh, Robert W

2006-06-01

To describe the events surrounding the personal and professional feud between Josef Hyrtl and Ernst Brücke and its impact on early investigations into the function of the semicircular canals of the inner ear. Published data in scientific journals and news media, documents at the Vienna Institute for the History of Medicine, published personal letters, and an interview with Brücke's great-grandson, Dr. Thomas Brücke. Although Hyrtl was instrumental in recruiting Brücke to the University of Vienna, the two professors soon became embroiled in a feud that persisted throughout their academic careers. The difference in approach of these two giants in their field is well illustrated by their views on the function of the semicircular canals of the inner ear. Based on their shape, Hyrtl concluded that they were important for directional hearing, whereas based on animal experiments, Brücke concluded that they were sense organs for equilibrium.

Vitamin D receptor deficiency impairs inner ear development in zebrafish

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kwon, Hye-Joo; Biology Department, Princess Nourah University, Riyadh 11671

The biological actions of vitamin D are largely mediated through binding to the vitamin D receptor (VDR), a member of the nuclear hormone receptor family, which regulates gene expression in a wide variety of tissues and cells. Mutations in VDR gene have been implicated in ear disorders (hearing loss and balance disorder) but the mechanisms are not well established. In this study, to investigate the role of VDR in inner ear development, morpholino-mediated gene knockdown approaches were used in zebrafish model system. Two paralogs for VDR, vdra and vdrb, have been identified in zebrafish. Knockdown of vdra had no effectmore » on ear development, whereas knockdown of vdrb displayed morphological ear defects including smaller otic vesicles with malformed semicircular canals and abnormal otoliths. Loss-of-vdrb resulted in down-regulation of pre-otic markers, pax8 and pax2a, indicating impairment of otic induction. Furthermore, zebrafish embryos lacking vdrb produced fewer sensory hair cells in the ears and showed disruption of balance and motor coordination. These data reveal that VDR signaling plays an important role in ear development. - Highlights: • VDR signaling is involved in ear development. • Knockdown of vdrb causes inner ear malformations during embryogenesis. • Knockdown of vdrb affects otic placode induction. • Knockdown of vdrb reduces the number of sensory hair cells in the inner ear. • Knockdown of vdrb disrupts balance and motor coordination.« less

Middle-Ear Pressure Gain and Cochlear Partition Differential Pressure in Chinchilla

PubMed Central

Ravicz, Michael E.; Slama, Michaël C.C.; Rosowski, John J.

2009-01-01

An important step to describe the effects of inner-ear impedance and pathologies on middle- and inner-ear mechanics is to quantify middle- and inner-ear function in the normal ear. We present middle-ear pressure gain GMEP and trans-cochlear-partition differential sound pressure ΔPCP in chinchilla from 100 Hz to 30 kHz derived from measurements of intracochlear sound pressures in scala vestibuli PSV and scala tympani PST and ear-canal sound pressure near the tympanic membrane PTM. These measurements span the chinchilla's auditory range. GMEP had constant magnitude of about 20 dB between 300 Hz and 20 kHz and phase that implies a 40-μs delay, values with some similarities to previous measurements in chinchilla and other species. ΔPCP was similar to GMEP below about 10 kHz and lower in magnitude at higher frequencies, decreasing to 0 dB at 20 kHz. The high-frequency rolloff correlates with the audiogram and supports the idea that middle-ear transmission limits high-frequency hearing, providing a stronger link between inner-ear macromechanics and hearing. We estimate the cochlear partition impedance ZCP from these and previous data. The chinchilla may be a useful animal model for exploring the effects of nonacoustic inner-ear stimulation such as “bone conduction” on cochlear mechanics. PMID:19945521

Inner ear test battery in guinea pig models - a review.

PubMed

Young, Yi-Ho

2018-06-01

This study reviewed the development of the inner ear test battery comprising auditory brainstem response (ABR), and caloric, ocular vestibular-evoked myogenic potential (oVEMP), and cervical vestibular-evoked myogenic potential (cVEMP) tests in guinea pig models at our laboratory over the last 20 years. Detailed description of the methodology for testing the small animals is also included. Inner ear disorders, i.e. ototoxicity, noise exposure, or perilymph fistula were established in guinea pig models first. One to four weeks after operation, each animal underwent ABR, oVEMP, cVEMP, and caloric tests. Then, animals were sacrificed for morphological study in the temporal bones. Inner ear endorgans can be comprehensively evaluated in guinea pig models via an inner ear test battery, which provides thorough information on the cochlea, saccule, utricle, and semicircular canal function of guinea pigs. Coupled with morphological study in the temporal bones of the animals may help elucidate the mechanism of inner ear disorders in humans. The inner ear test battery in guinea pig models may encourage young researchers to perform basic study in animals and stimulate the progress of experimental otology which is in evolution.

The Pitfalls and Important Distances in Temporal Bone HRCT of the Subjects with High Jugular Bulbs - Preliminary Report.

PubMed

Inal, Mikail; Muluk, Nuray B; Dağ, Ersel; Arıkan, Osman K; Kara, Simay A

2015-01-01

High jugular bulb (HJB) may be detected unilaterally or bilaterally in temporal bone high resolution computerized tomography (HRCT). In this retrospective study, we investigated the pitfalls and important surgical distances in patients with unilateral and bilateral HJB via temporal bone HRCT. In this preliminary report, the study group consisted of 20 adult patients (12 male, 8 female), or 40 ears, all of which underwent temporal bone HRCT. We divided them into groups that consisted of bilateral HJB (14 ears), unilateral HJB (13 ears), and control (No HJB, 13 ears). The anotomical relationships of the sigmoid sinus, jugular bulb, and carotid artery with several landmarks in the temporal bone were studied via temporal bone axial and coronal HRCT. The shortest distances between certain points were measured. These measurements were analyzed in respect to pneumatization. Dehiscence on the jugular bulb (JB) and internal carotid artery (ICA) and the dominance of JB were also evaluated for all of the groups. In the axial sections of the temporal bone HRCTs, the sigmois sinus (SS)-external auditory canal (EAC) distance of the bilateral HJB group (14.00±1.17 mm) was significantly lower than that of the control group (16.46±2.14 mm). The JB-posteromedial points of the umbo on the ear drum (ED) distance of the bilateral HJB (6.28±1.72 mm) and the unilateral HJB groups (7.23±2.00 mm) were significantly lower than that of the control group (11.15±2.30 mm). In the coronal sections of the temporal bone HRCT, the JB-F distance of the bilateral HJB group (5.42±2.10 mm) was significantly lower than that of the control group (8.30±2.28 mm). As the mastoid pneumatisation and mastoid volume increased, the percentage of ICA-dehiscence and the percentage of JB-dehiscence increased. In subjects with well-pneumatised mastoids, the doctors should be aware of the increased risk of ICA-dehiscence and JB-dehiscence. These measurements should be done in greater series to yield more thorough knowledge.

Measurement of body temperature by use of auricular thermometers versus rectal thermometers in dogs with otitis externa.

PubMed

González, A Michelle; Mann, F A; Preziosi, Diane E; Meadows, Richard L; Wagner-Mann, Colette C

2002-08-01

To compare measurements of body temperature obtained with auricular thermometers versus rectal thermometers in dogs with otitis externa. Prospective study. 100 client-owned dogs: 50 with and 50 without clinical evidence of otitis externa. Dogs were evaluated for the presence of otitis externa on the basis of clinical signs, otoscopic examination, and cytologic evaluation of ear exudate. Auricular and rectal temperatures were obtained simultaneously in all dogs prior to and following ear examination. There was a high correlation between auricular and rectal temperatures in dogs with otitis externa both prior to and after ear manipulation. Significant differences were not detected in temperature measurements among dogs with different degrees of otitis externa. Auricular temperature readings obtained by use of an auricular thermometer in dogs with otitis externa are accurate measurements of body temperature, compared with rectal temperature measurements. Temperature measurements are reliable before and after examination of the ear canal.

Knowledge, Attitude and Practice of Ear Care in Coastal Karnataka.

PubMed

Dosemane, Deviprasad; Ganapathi, Keerthan; Kanthila, Jayashree

2015-12-01

Ear as an organ is necessary for the perception of sound and body balance. Ear infection, diabetes mellitus, hypertension and excessive use of mobile phone for listening to music at high volume all can reduce hearing. No earlier study was available in the costal Karnataka population, regarding the practice of ear care. The study objective was to ascertain the level of knowledge of the community regarding ear care, to find out whether some of the common conditions affecting hearing are known and to find out the common practices involved in maintaining ear hygiene. This cross-sectional study was conducted on 500 subjects in two tertiary care hospitals by convenient sampling, using self-administered questionnaire. Knowledge, Attitude and Practice across the age groups, religion & education background were studied. Across different education groups, 66.7%-90% did not know that 'cold' can cause ear infection and 46.7%-75.0% did not know that diabetes and hypertension can reduce hearing. When there is ear pain or discharge, people put ear drops available at home in 48.3%-75.0% across 3 age groups; 58.5%-61.5% across 3 religions and 44.8%-67.9% across 5 education groups. No statistically significant difference was found in the practice of pouring oil into ears across religions. A total of 58.6%-100% daily clean inside the ear and 70-100% use cotton buds. General perception of the people is that ear is necessary only for hearing. Majority did not know that nasal infection can affect the ear and that DM and hypertension can cause hearing loss. When there is ear pain and discharge, most of the adults put drops that are available at home. Pouring oil into the ears and cleaning inside the ear canals is routinely practiced in costal Karnataka.

Adenoid cystic carcinoma of the external ear: a population based study.

PubMed

Green, Ross W; Megwalu, Uchechukwu C

2016-01-01

To determine the incidence of adenoid cystic carcinoma of the external ear in the United States, and to evaluate the clinical characteristics and survival outcomes associated with the disease. Data were extracted from the Surveillance, Epidemiology, and End Results (SEER) 18 Database of the National Cancer Institute. The study cohort included patients diagnosed with adenoid cystic carcinoma of the external ear from 1973 to 2012. The incidence of adenoid cystic carcinoma of the external ear was 0.004 per 100,000. The SEER database identified 66 patients meeting the inclusion criteria. Nodal metastasis was noted in 13.1% of patients, while 7.9% had distant metastasis. Distant metastasis was associated with worse overall survival (HR 10.18). However, nodal metastasis had no impact on overall survival (HR 0.15, p = 0.09). Surgery alone was associated with improved overall survival (HR 0.26), compared with combination surgery and radiotherapy, while radiotherapy alone was associated with worse overall survival (HR 20.12). Increasing age (HR 1.12) and black race (HR 6.83) were associated with worse overall survival, while female sex (HR 0.26) was associated with improved overall survival. ACC of the external ear is rare. Distant metastasis is a poor prognostic factor. However, nodal metastasis does not appear to impact survival. Advanced age, black race, and male sex are also poor prognostic factors. Surgical resection alone is associated with better survival than combination surgical resection and radiation, or radiotherapy alone. Copyright © 2016 Elsevier Inc. All rights reserved.

An objective comparison of leakage between commonly used earplugs.

PubMed

Alt, Jeremiah A; Collins, William O

2012-01-01

We sought to determine the efficacy of commonly used earplugs using an anatomically correct ear model. The total volume and rate of water that leaked past the earplug and subsequent defect in the tympanic membrane over separately measured 30, 60, 120, and 180-second intervals were recorded. Scenarios tested included a control with no earplug, custom molded earplug (Precision Laboratories, Orlando, FL), Mack's plug (Warren, MI), Doc's plug (Santa Cruz, CA), and cotton balls coated with petroleum jelly. All plugs tested resulted in less leakage at all time points when compared with no plug (P < .05). At 30 seconds, the custom molded, Mack's and Doc's plugs all showed significantly less leakage when compared with the cotton ball coated with petroleum jelly (P < .05). At 60, 120, and 180 seconds, Mack's, Doc's, and the cotton plugs all showed significantly less leakage compared with the customized plug (P < .05). At 120 and 180 seconds, Mack's plugs had significant less leakage than the cotton plug (P < .05). Among the types of plugs, the molded variety (Mack's) showed the least volume and lowest leakage rate (f(4,45) = 94 [P < .001]). In addition, Doc's and cotton balls coated with petroleum jelly were more effective than the customized earplugs. If the clinician feels that middle ear and external canal water exposure should be minimized, then use of earplugs, particularly the moldable variety, merits further consideration. Copyright © 2012 Elsevier Inc. All rights reserved.

Earable TEMPO: A Novel, Hands-Free Input Device that Uses the Movement of the Tongue Measured with a Wearable Ear Sensor

PubMed Central

Kondo, Hisashi

2018-01-01

In this study, an earphone-type interface named “earable TEMPO” was developed for hands-free operation, wherein the user can control the device by simply pushing the tongue against the roof of the mouth for about one second. This interface can be used to start and stop the music from a portable audio player. The earable TEMPO uses an earphone-type sensor equipped with a light emitting diode (LED) and a phototransistor to optically measure shape variations that occur in the external auditory meatus when the tongue is pressed against the roof of the mouth. To evaluate the operation of the earable TEMPO, experiments were performed on five subjects (men and women aged 22–58) while resting, chewing gum (representing mastication), and walking. The average accuracy was 100% while resting and chewing and 99% while walking. The precision was 100% under all conditions. The average recall value of the five subjects was 92%, 90%, and 48% while resting, masticating, and walking, respectively. All subjects were reliably able to perform the action of pressing the tongue against the roof of the mouth. The measured shape variations in the ear canal were highly reproducible, indicating that this method is suitable for various applications such as controlling a portable audio player. PMID:29494482

Prevalence, prenatal diagnosis and clinical features of oculo-auriculo-vertebral spectrum: a registry-based study in Europe

PubMed Central

Barisic, Ingeborg; Odak, Ljubica; Loane, Maria; Garne, Ester; Wellesley, Diana; Calzolari, Elisa; Dolk, Helen; Addor, Marie-Claude; Arriola, Larraitz; Bergman, Jorieke; Bianca, Sebastiano; Doray, Berenice; Khoshnood, Babak; Klungsoyr, Kari; McDonnell, Bob; Pierini, Anna; Rankin, Judith; Rissmann, Anke; Rounding, Catherine; Queisser-Luft, Annette; Scarano, Gioacchino; Tucker, David

2014-01-01

Oculo-auriculo-vertebral spectrum is a complex developmental disorder characterised mainly by anomalies of the ear, hemifacial microsomia, epibulbar dermoids and vertebral anomalies. The aetiology is largely unknown, and the epidemiological data are limited and inconsistent. We present the largest population-based epidemiological study to date, using data provided by the large network of congenital anomalies registries in Europe. The study population included infants diagnosed with oculo-auriculo-vertebral spectrum during the 1990–2009 period from 34 registries active in 16 European countries. Of the 355 infants diagnosed with oculo-auriculo-vertebral spectrum, there were 95.8% (340/355) live born, 0.8% (3/355) fetal deaths, 3.4% (12/355) terminations of pregnancy for fetal anomaly and 1.5% (5/340) neonatal deaths. In 18.9%, there was prenatal detection of anomaly/anomalies associated with oculo-auriculo-vertebral spectrum, 69.7% were diagnosed at birth, 3.9% in the first week of life and 6.1% within 1 year of life. Microtia (88.8%), hemifacial microsomia (49.0%) and ear tags (44.4%) were the most frequent anomalies, followed by atresia/stenosis of external auditory canal (25.1%), diverse vertebral (24.3%) and eye (24.3%) anomalies. There was a high rate (69.5%) of associated anomalies of other organs/systems. The most common were congenital heart defects present in 27.8% of patients. The prevalence of oculo-auriculo-vertebral spectrum, defined as microtia/ear anomalies and at least one major characteristic anomaly, was 3.8 per 100 000 births. Twinning, assisted reproductive techniques and maternal pre-pregnancy diabetes were confirmed as risk factors. The high rate of different associated anomalies points to the need of performing an early ultrasound screening in all infants born with this disorder. PMID:24398798

Study of a temporal bone of Homo heildelbergensis.

PubMed

Urquiza, Rafael; Botella, Miguel; Ciges, Miguel

2005-05-01

The characteristic features of the Hh specimen conformed to those of other Pleistocene human fossils, indicating strong cranial structures and a heavy mandible. The mastoid was large and suggested a powerful sternocleidomastoid muscle. The inner ear and tympanic cavities were similar in size and orientation, suggesting that their functions were probably similar. Our observations suggest that the left ear of this Hh specimen was healthy. The large canaliculo-fenestral angle confirms that this ancestor was bipedal. It also strongly suggests that Hh individuals were predisposed to develop certain pathologies of the labyrinth capsule associated with bipedalism, in particular otosclerosis. We studied a temporal bone of Homo heidelbergensis (Hh) in order to investigate the clinical and physiological implications of certain morphological features, especially those associated with the evolutionary reorganization of the inner ear. The bone, found in a breach of a cave near MAáaga in southern Spain, together with Middle Upper Pleistocene faunal remains, is >300000 years old. Four analytical methods were employed. A 3D high-resolution surface laser scan was used for anatomical measurements. For the sectional analysis of the middle and inner ears of Hh we used high-resolution CT, simultaneously studying a normal temporal bone from Homo sapiens sapiens (Hss). To study the middle and inner ear spaces we used 3D reconstruction CT preceded by an intra-bone air shielding technique. To examine the tympanic cavities and measure the canaliculo fenestral angle, we used a special minimally invasive endoscopic procedure. The surface, sectional and 3D CT examinations showed that the Hh specimen was generally more robust and larger than the Hss specimen. It had a large glenoid fossa. The external meatus was wide and deep. The middle ear, and especially the mastoid, was large and widely pneumatized. There were no appreciable differences in the position and size of the labyrinthine spaces and tympanic cavity. The dimensions of the semicircular canals were similar to those of the Hss specimen. Endoscopy revealed normal, healthy tympanic walls and an ossicle fragment in the atticum that probably belonged to the body of the malleus. The diameters of the fallopian duct and the tympanic opening of the Eustachian tube were large. The canaliculo-fenestral angle was approximately 114 degrees

Inner ear anatomy in Waardenburg syndrome: radiological assessment and comparison with normative data.

PubMed

Kontorinis, Georgios; Goetz, Friedrich; Lanfermann, Heinrich; Luytenski, Stefan; Giesemann, Anja M

2014-08-01

As patients with Waardenburg syndrome (WS) represent potential candidates for cochlear implantation, their inner ear anatomy is of high significance. There is an ongoing debate whether WS is related to any inner ear dysplasias. Our objective was to evaluate radiologically the inner ear anatomy in patients with WS and identify any temporal bone malformations. A retrospective case review was carried out in a tertiary, referral center. The high resolution computed tomography (HRCT) scans of the temporal bone from 20 patients (40 ears) with WS who were managed for deafness in a tertiary referral center from 1995 to 2012 were retrospectively examined. Measurements of 15 different inner ear dimensions, involving the cochlea, the vestibule, the semicircular canals and the internal auditory meatus, as well as measurements of the vestibular aqueduct, were performed independently by two neuroradiologists. Finally, we compared the results from the WS group with a control group consisting of 50 normal hearing subjects (100 ears) and with previously reported normative values. Inner ear malformations were not found in any of the patients with WS. All measured inner ear dimensions were within the normative values compiled by our study group as well as by others. Inner ear malformations are not characteristic for all types of WS; however, certain rare subtypes might be related to inner ear deformities. Normative cochleovestibular dimensions that can help in assessing the temporal bone anatomy are provided. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Physiologic Responses Produced by Active and Passive Personal Cooling Vests

NASA Technical Reports Server (NTRS)

Ku, Yu-Tsuan E.; Lee, Hank C.; Montgomery, Leslie D.; Luna, Bernadette

2000-01-01

Personal thermoregulatory systems which provide chest cooling are used in the industrial and aerospace environments to alleviate thermal stress. However, little information is available regarding the physiologic and circulatory changes produced by routine operation of these systems. The objectives of this study were to document and compare the subjects' response to three cooling vests in their recommended configurations. The Life Enhancement Tech (LET) lightweight active cooling vest with cap, the MicroClimate Systems Change of Phase garment (MCS), and the Steele Vest were each used to cool the chest regions of 12 male and 8 female Healthy subjects (21 to 69 yr.) in this study. The subjects, seated in an upright position at normal room temperature (approx. 22 C), were tested for 60 min. with one of the cooling garments. The LET active garment had an initial coolant fluid inlet temperature of 60 F, and was ramped down to 50 F. Oral, right and left ear canal temperatures were logged manually every 5 min. Arm, leg, chest and rectal temperatures; heart rate; and respiration were recorded continuously on a U.F.I., Inc. Biolog ambulatory monitor. For men, all three vests had similar, significant cooling effects. Decreases in the average rectal temperature, oral temperature, and ear canal temperatures were approximately 0.2 C, 0.2 C and 0.1 C, respectively. In contrast to the men, the female subjects wearing the MCS and Steel vests had similar cooling responses in which the core temperature remained elevated and oral and ear canal temperatures did not drop. The LET active garment cooled most of the female subjects in this study; rectal, oral and ear temperature decreased about 0.2 C, 0.3 C and 0.3 C, respectively. These results show that the garment configurations tested do not elicit a similar thermal response in all subjects. A gender difference is evident. The LET active garment configuration was most effective in decreasing temperatures of the female subjects; the MCS vest was least effective. For male subjects, the three vests appear to be more nearly equivalent. The active garment system under study included a cooling cap, which may account for some of the difference in response.

The Role of Zic Genes in Inner Ear Development in the Mouse: Exploring Mutant Mouse Phenotypes

PubMed Central

Chervenak, Andrew P.; Bank, Lisa M.; Thomsen, Nicole; Glanville-Jones, Hannah C; Skibo, Jonathan; Millen, Kathleen J.; Arkell, Ruth M.; Barald, Kate F.

2014-01-01

Background Murine Zic genes (Zic1-5) are expressed in the dorsal hindbrain and in periotic mesenchyme (POM) adjacent to the developing inner ear. Zic genes are involved in developmental signaling pathways in many organ systems, including the ear, although their exact roles haven't been fully elucidated. This report examines the role of Zic1, Zic2, and Zic4 during inner ear development in mouse mutants in which these Zic genes are affected Results Zic1/Zic4 double mutants don't exhibit any apparent defects in inner ear morphology. By contrast, inner ears from Zic2kd/kd and Zic2Ku/Ku mutants have severe but variable morphological defects in endolymphatic duct/sac and semicircular canal formation and in cochlear extension in the inner ear. Analysis of otocyst patterning in the Zic2Ku/Ku mutants by in situ hybridization showed changes in the expression patterns of Gbx2 and Pax2. Conclusions The experiments provide the first genetic evidence that the Zic genes are required for morphogenesis of the inner ear. Zic2 loss-of-function doesn't prevent initial otocyst patterning but leads to molecular abnormalities concomitant with morphogenesis of the endolymphatic duct. Functional hearing deficits often accompany inner ear dysmorphologies, making Zic2 a novel candidate gene for ongoing efforts to identify the genetic basis of human hearing loss. PMID:25178196

Inner ear disorders.

PubMed

Smouha, Eric

2013-01-01

To present a framework for the diagnosis and treatment of inner ear disorders, with an emphasis on problems common to neuro-rehabilitation. Disorders of the inner ear can cause hearing loss, tinnitus, vertigo and imbalance. Hearing loss can be conductive, sensorineural, or mixed; conductive hearing loss arises from the ear canal or middle ear, while sensorineural hearing loss arises from the inner ear or auditory nerve. Vertigo is a hallucination of motion, and is the cardinal symptom of vestibular system disease. It should be differentiated from other causes of dizziness: gait imbalance, disequilibrium, lightheadedness (pre-syncope). Vertigo can be caused by problems in the inner ear or central nervous system. The diagnosis of inner ear disorders begins with a targeted physical examination. The initial work-up of hearing loss is made by audiometry, and vertigo by electronystagmography (ENG). Supplemental tests and MRI are obtained when clinically indicated. The clinical pattern and duration of vertigo are the most important clinical features in the diagnosis. Common inner ear causes of vertigo include: vestibular neuritis (sudden, unilateral vestibular loss), Meniere's disease (episodic vertigo), benign paroxysmal positional vertigo (BPPV), and bilateral vestibular loss. Common central nervous system causes of vertigo include: post concussion syndrome, cervical vertigo, vestibular migraine, cerebrovascular disease, and acoustic neuroma. A basic knowledge of vestibular physiology, coupled with a understanding of common vestibular syndromes, will lead to correct diagnosis and treatment in most cases.

21 CFR 524.1610 - Orbifloxacin, mometasone furoate monohydrate, and posaconazole suspension.

Code of Federal Regulations, 2010 CFR

2010-04-01

... HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS OPHTHALMIC AND TOPICAL DOSAGE FORM NEW ANIMAL DRUGS § 524.1610 Orbifloxacin, mometasone furoate monohydrate, and posaconazole... 8 drops into the ear canal. Therapy should continue for 7 consecutive days. (2) Indications for use...

[Analysis of the speech discrimination scores of patients with congenital unilateral microtia and external auditory canal atresia in noise].

PubMed

Zhang, Y; Li, D D; Chen, X W

2017-06-20

Objective: Case-control study analysis of the speech discrimination of unilateral microtia and external auditory canal atresia patients with normal hearing subjects in quiet and noisy environment. To understand the speech recognition results of patients with unilateral external auditory canal atresia and provide scientific basis for clinical early intervention. Method: Twenty patients with unilateral congenital microtia malformation combined external auditory canal atresia, 20 age matched normal subjects as control group. All subjects used Mandarin speech audiometry material, to test the speech discrimination scores (SDS) in quiet and noisy environment in sound field. Result: There's no significant difference of speech discrimination scores under the condition of quiet between two groups. There's a statistically significant difference when the speech signal in the affected side and noise in the nomalside (single syllable, double syllable, statements; S/N=0 and S/N=-10) ( P <0.05). There's no significant difference of speech discrimination scores when the speech signal in the nomalside and noise in the affected side. There's a statistically significant difference in condition of the signal and noise in the same side when used one-syllable word recognition (S/N=0 and S/N=-5) ( P <0.05), while double syllable word and statement has no statistically significant difference ( P >0.05). Conclusion: The speech discrimination scores of unilateral congenital microtia malformation patients with external auditory canal atresia under the condition of noise is lower than the normal subjects. Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.

Survey of Malassezia sp and dermatophytes in the cutaneous microbiome of free-ranging golden-headed lion tamarins (Leontopithecus chrysomelas - Kuhl, 1820).

PubMed

Neves, Juan Ja; Francelino, Marcelo; Silva, Flavia Gl; Baptista, Luana Cl; Bueno, Marina G; Catão-Dias, José L; Molina, Camila; Kierulff, Maria Cm; Pissinatti, Alcides; Coutinho, Selene DA

2017-06-01

Data about the presence of fungi on the cutaneous surface of wild animals are scarce. The aim of this study was to survey dermatophytes and Malassezia sp in the external ear canal and haircoat of Leontopithecus chrysomelas. A total of 928 clinical samples were collected from 232 animals: For Malassezia screening 696 samples were studied, 464 of cerumen and 232 of haircoat; another 232 haircoat samples were studied for dermatophyte analysis. A geophilic dermatophyte, Microsporum cookie, was isolated from one young female. Lipodependent Malassezia was isolated from 76 animals and 87 clinical samples, 26 from the cerumen and 61 from the haircoat (statistically significant); there were no differences related to gender and age. Results suggested that lipodependent Malassezia is part of the skin microbiome of these animals. The prevalence of dermatophytes was too low and probably not relevant for the health of the studied population. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Fast Reverse Propagation of Sound in the Living Cochlea

PubMed Central

He, Wenxuan; Fridberger, Anders; Porsov, Edward; Ren, Tianying

2010-01-01

Abstract The auditory sensory organ, the cochlea, not only detects but also generates sounds. Such sounds, otoacoustic emissions, are widely used for diagnosis of hearing disorders and to estimate cochlear nonlinearity. However, the fundamental question of how the otoacoustic emission exits the cochlea remains unanswered. In this study, emissions were provoked by two tones with a constant frequency ratio, and measured as vibrations at the basilar membrane and at the stapes, and as sound pressure in the ear canal. The propagation direction and delay of the emission were determined by measuring the phase difference between basilar membrane and stapes vibrations. These measurements show that cochlea-generated sound arrives at the stapes earlier than at the measured basilar membrane location. Data also show that basilar membrane vibration at the emission frequency is similar to that evoked by external tones. These results conflict with the backward-traveling-wave theory and suggest that at low and intermediate sound levels, the emission exits the cochlea predominantly through the cochlear fluids. PMID:20513393

Scedosporium apiospermum: a rare cause of malignant otitis externa.

PubMed

McLaren, Oliver; Potter, Christian

2016-09-09

A 79-year-old man, with a history of well-controlled diabetes mellitus, presented with left-sided otalgia. With an initial diagnosis of simple otitis externa, he was discharged on topical drops. He represented 2 months later with worsening otalgia and discharge. A diagnosis of malignant otitis externa was made based on clinical and radiological findings. Intravenous Tazocin and Gentamicin were given based on previous bacterial culture from ear swabs. The patient failed to improve and developed left-sided facial nerve palsy. His condition stabilised following a change in antimicrobial therapy and his management continued in the community on intravenous Meropenem with twice weekly aural toilet. Repeated nuclear medicine imaging failed to demonstrate resolution. A bony sequestration was removed from the external auditory canal in the outpatient clinic, which following extended culture grew Scedosporium apiospermum; his management was subsequently changed to oral Voriconazole. This led to rapid clinical improvement and disease resolution over a 6 -week period. 2016 BMJ Publishing Group Ltd.

Three cases of successful microvascular ear replantation after bite avulsion injury.

PubMed

Schonauer, Fabrizio; Blair, James W; Moloney, Dominique M; Teo, T C; Pickford, Mark A

2004-01-01

We present three cases of sub-total amputation of the external ear caused by bite avulsion injury. The ears were all successfully replanted despite us being unable to perform a venous anastomosis in one case. These outcomes support attempted microsurgical replantation for total or sub-total amputations of the ear, as successful replantation is the most effective surgical option.

Canal switch and re-entry phenomenon in benign paroxysmal positional vertigo: difference between immediate and delayed occurrence.

PubMed

Dispenza, F; DE Stefano, A; Costantino, C; Rando, D; Giglione, M; Stagno, R; Bennici, E

2015-04-01

This prospective study was designed to evaluate the differences between immediate and delayed canal re-entry of otoliths after therapeutic manoeuvres in patients with benign paroxysmal positional vertigo (BPPV). A total of 196 patients with BPPV were visited and 127 matched our inclusion criteria. The mean age was 54.74 years. The horizontal semicircular canal (HSC) was involved in 30 cases and the posterior semicircular canal (PSC) in 97 patients. Patients with hearing loss in the ear affected by BPPV have a more recurrent form, compared to those with normal hearing. An immediate canal re-entry was recorded in 3 patients with HSC BPPV, all with geotropic nystagmus. In 7 patients with PSC BPPV, the immediate canal re-entry was detected and the delayed form was noted in 5 patients. The patients with the delayed canal re-entry underwent more than 2 previous manoeuvres. The canal re-entry was not related to the manoeuvre performed. The timing of the Dix-Hallpike test to verify the resolution of the BPPV had a significant role in immediate canal re-entry. A recurrence in the follow-up at least one month after treatment was recorded in 20 patients and was more frequent in patients that had canal re-entry. The canal re-entry or canal switch is a clinical entity that should be kept in mind of the neurotologist when approaching BPPV patients. It is important to distinguish it from recurrence when delayed and from manoeuvre failure when immediate. The timing of manoeuvre performing, in particular the final verification test after therapeutic sessions, is important to prevent the immediate reflux of particles into canals.

Optical diffusion property of cerumen from ear canal and correlation to metal content measured by synchrotron x-ray absorption

NASA Astrophysics Data System (ADS)

Holden, Todd; Dehipawala, Sumudu; Cheung, E.; Golebiewska, U.; Schneider, P.; Tremberger, G., Jr.; Kokkinos, D.; Lieberman, D.; Dehipawala, Sunil; Cheung, T.

2012-03-01

Human (and other mammals) would secrete cerumen (ear wax) to protect the skin of the ear canal against pathogens and insects. The studies of biodiversity of pathogen in human include intestine microbe colony, belly button microbe colony, etc. Metals such as zinc and iron are essentials to bio-molecular pathways and would be related to the underlying pathogen vitality. This project studies the biodiversity of cerumen via its metal content and aims to develop an optical probe for metal content characterization. The optical diffusion mean free path and absorption of human cerumen samples dissolved in solvent have been measured in standard transmission measurements. EXFAS and XANES have been measured at Brookhaven Synchrotron Light Source for the determination of metal contents, presumably embedded within microbes/insects/skin cells. The results show that a calibration procedure can be used to correlate the optical diffusion parameters to the metal content, thus expanding the diagnostic of cerumen in the study of human pathogen biodiversity without the regular use of a synchrotron light source. Although biodiversity measurements would not be seriously affected by dead microbes and absorption based method would do well, the scattering mean free path method would have potential to further study the cell based scattering centers (dead or live) via the information embedded in the speckle pattern in the deep-Fresnel zone.

The Effect of Increased Intracranial Pressure on Vestibular Evoked Myogenic Potentials in Superior Canal Dehiscence Syndrome

PubMed Central

Janky, Kristen L.; Zuniga, M. Geraldine; Schubert, Michael C; Carey, John P

2014-01-01

Objective To determine if vestibular evoked myogenic potential (VEMP) responses change during inversion in patients with superior canal dehiscence syndrome (SCDS) compared to controls. Methods Sixteen subjects with SCDS (mean: 43, range 30–57 years) and 15 age-matched, healthy subjects (mean: 41, range 22–57 years) completed cervical VEMP (cVEMP) in response to air conduction click stimuli and ocular VEMP (oVEMP) in response to air conduction 500 Hz tone burst stimuli and midline tap stimulation. All VEMP testing was completed in semi-recumbent and inverted conditions. Results SCDS ears demonstrated significantly larger oVEMP peak-to-peak amplitudes in comparison to normal ears in semi-recumbency. While corrected cVEMP peak-to-peak amplitudes were larger in SCDS ears; this did not reach significance in our sample. Overall, there was not a differential change in o- or cVEMP amplitude with inversion between SCDS and normal subjects. Conclusions Postural-induced changes in o- and cVEMP responses were measured in the steady state regardless of whether the labyrinth was intact or dehiscent. Significance VEMP responses are blunted during inversion. Although steady-state measurements of VEMPs during inversion do not increase diagnostic accuracy for SCDS, the findings suggest that inversion may provide more general insights into the equilibration of pressures between intracranial and intralabyrinthine fluids. PMID:25103787

Development of a finite element model of the middle ear.

PubMed

Williams, K R; Blayney, A W; Rice, H J

1996-01-01

A representative finite element model of the healthy ear is developed commencing with a description of the decoupled isotropic tympanic membrane. This model was shown to vibrate in a manner similar to that found both numerically (1, 2) and experimentally (8). The introduction of a fibre system into the membrane matrix significantly altered the modes of vibration. The first mode "remains as a piston like movement as for the isotropic membrane. However, higher modes show a simpler vibration pattern similar to the second mode but with a varying axis of movement and lower amplitudes. The introduction of a malleus and incus does not change the natural frequencies or mode shapes of the membrane for certain support conditions. When constraints are imposed along the ossicular chain by simulation of a cochlear impedance term then significantly altered modes can occur. More recently a revised model of the ear has been developed by the inclusion of the outer ear canal. This discretisation uses geometries extracted from a Nuclear Magnetic resonance scan of a healthy subject and a crude inner ear model using stiffness parameters ultimately fixed through a parameter tuning process. The subsequently tuned model showed behaviour consistent with previous findings and should provide a good basis for subsequent modelling of diseased ears and assessment of the performance of middle ear prostheses.

[Genetic deafness].

PubMed

Marcolla, A; Bouchetemble, P; Lerosey, Y; Marie, J-P; Dehesdin, D

2006-06-01

The aim of this study was to review the different types of genetic deafness. We describe syndromic and isolated sensorineural deafness and transmission deafness. Genetic sensorineural syndromic deafness represents 30% of cases of genetic deafness. A frequent cause is Pendred syndrome, which associates congenital sensorineural deafness with goitre and malformations of the inner ear which can be identified on computed tomography scan. Isolated deafness which is responsible for 70% of cases of genetic deafness is then outlined. Among the different types of isolated deafness, 80% are autosomal recessive disorders. A frequent form of autosomal recessive deafness is due to mutations in the connexin 26 gene. Lastly, we detail transmission deafness dominated by aplasia. Major aplasia is characterized by a malformation of the external ear associated with malformations of the middle ear whereas, minor aplasia corresponds to a malformation of the middle ear, sometimes associated with minor external ear malformations. For each type of deafness we propose a systematic assessment.

Acoustic stimulation on the round window for active middle ear implants.

PubMed

Seong, Kiwoong; Lee, Kyuyup; Puria, Sunil; Cho, Jin-Ho

2018-06-01

Many clinical reports have discussed the effectiveness of stimulating the ear's round window (RW) with a tool to mitigate conductive and mixed hearing loss. The RW is one of the two openings from the middle ear into the inner ear. Various methods have been proposed to construct a highly efficient, easily implanted, and reliable RW transducer. Devices, however, such as floating mass transducers, have difficulty establishing proper contact without some degree of bone incision around the RW. Additionally, vibration energy may not be fully transmitted to the cochlea, but instead will be spread through the soft tissue around the transducer. We propose a more direct RW stimulation with very high acoustical impedance using a receiver that is a volume velocity source. We expect this source to overcome large acoustic impedance by maximizing sound pressure in a confined space, the RW niche. To verify the effectiveness of the proposed method, ear canal pressure, RW pressure, and stapes velocity are measured by acoustic RW stimulation of human temporal bones. Copyright © 2018 Elsevier Ltd. All rights reserved.

Experimental research on preventing mechanical phlebitis arising from indwelling needles in intravenous therapy by external application of mirabilite

PubMed Central

Lu, Yanyan; Hao, Chunyan; He, Wubin; Tang, Can; Shao, Zhenya

2018-01-01

Various types of complications arising from intravenous indwelling needles have become a challenge in clinical care. It is urgent to seek a simple and cost-effective method for prevention and treatment of phlebitis. We investigated the roles of mirabilite in preventing and treating phlebitis caused by intravenous indwelling needles and provide guidance for prevention and treatment of mechanical phlebitis caused by intravenous indwelling needles. A total of 57 healthy congeneric big-eared New Zealand rabbits were randomly divided into 3 groups: blank control, indwelling needle, and group with external application of mirabilite. The ear vein of each rabbit was punctured with an intravenous indwelling needle. The ear vein specimens were taken at 3, 5, and 7 days after indwelling. The hematoxylin and eosin stained pathological tissue sections of the ear veins of the rabbits in each group were observed. The expression levels of IL-1 and IL-6, and tumour necrosis factor-α (TNF-α) in the vascular tissue of the ear veins of the rabbits in each group were detected with the immunofluorescence method. In the blank control group, there was no inflammatory cellular infiltration and no proliferation of fibrous tissue around the vascular wall. With the increase of the indwelling time, proliferation of fibrous tissue in vascular wall, increased inflammatory cellular infiltration and organized thrombus in the vascular tissue occurred in the ear veins of the rabbits in the indwelling needle group and group with external application of mirabilite. Compared with the indwelling needle group, the group with external application of mirabilite had significantly decreased fibrous tissue in the vascular wall and significantly decreased inflammatory cellular infiltration. At the same point in indwelling time, the expression levels of IL-1, IL-6, and TNF-α in the indwelling needle and group with external application of mirabilite were significantly higher than that in the blank control group (P<0.05). The expression levels of IL-1, IL-6, and TNF-α in the group with external application of mirabilite were lower than that in the indwelling needle group (P<0.05). The expression levels of IL-1, IL-6, and TNF-α are positively correlated with the indwelling time within the same group at different points in time. In conclusion, external application of mirabilite can significantly decrease infiltration of venous inflammatory cells of the rabbit ear margin, proliferation of fibrous tissue and thrombosis in the vascular wall, significant decrease the expression levels of IL-1, IL-6, and TNF-α in the mechanical phlebitis caused by intravenous indwelling needles, and decrease the inflammatory responses of the ear veins of rabbits. PMID:29250150

Experimental research on preventing mechanical phlebitis arising from indwelling needles in intravenous therapy by external application of mirabilite.

PubMed

Lu, Yanyan; Hao, Chunyan; He, Wubin; Tang, Can; Shao, Zhenya

2018-01-01

Various types of complications arising from intravenous indwelling needles have become a challenge in clinical care. It is urgent to seek a simple and cost-effective method for prevention and treatment of phlebitis. We investigated the roles of mirabilite in preventing and treating phlebitis caused by intravenous indwelling needles and provide guidance for prevention and treatment of mechanical phlebitis caused by intravenous indwelling needles. A total of 57 healthy congeneric big-eared New Zealand rabbits were randomly divided into 3 groups: blank control, indwelling needle, and group with external application of mirabilite. The ear vein of each rabbit was punctured with an intravenous indwelling needle. The ear vein specimens were taken at 3, 5, and 7 days after indwelling. The hematoxylin and eosin stained pathological tissue sections of the ear veins of the rabbits in each group were observed. The expression levels of IL-1 and IL-6, and tumour necrosis factor-α (TNF-α) in the vascular tissue of the ear veins of the rabbits in each group were detected with the immunofluorescence method. In the blank control group, there was no inflammatory cellular infiltration and no proliferation of fibrous tissue around the vascular wall. With the increase of the indwelling time, proliferation of fibrous tissue in vascular wall, increased inflammatory cellular infiltration and organized thrombus in the vascular tissue occurred in the ear veins of the rabbits in the indwelling needle group and group with external application of mirabilite. Compared with the indwelling needle group, the group with external application of mirabilite had significantly decreased fibrous tissue in the vascular wall and significantly decreased inflammatory cellular infiltration. At the same point in indwelling time, the expression levels of IL-1, IL-6, and TNF-α in the indwelling needle and group with external application of mirabilite were significantly higher than that in the blank control group (P<0.05). The expression levels of IL-1, IL-6, and TNF-α in the group with external application of mirabilite were lower than that in the indwelling needle group (P<0.05). The expression levels of IL-1, IL-6, and TNF-α are positively correlated with the indwelling time within the same group at different points in time. In conclusion, external application of mirabilite can significantly decrease infiltration of venous inflammatory cells of the rabbit ear margin, proliferation of fibrous tissue and thrombosis in the vascular wall, significant decrease the expression levels of IL-1, IL-6, and TNF-α in the mechanical phlebitis caused by intravenous indwelling needles, and decrease the inflammatory responses of the ear veins of rabbits.

Preventing Cauliflower Ear with a Modified Tie-Through Technique.

ERIC Educational Resources Information Center

Dimeff, Robert J.; Hough, David O.

1989-01-01

Describes a quick, simple tie-through suture technique (in which a collodion packing is secured to the auricle with two buttons) for preventing cauliflower ear following external ear trauma in wrestlers and boxers. The technique ensures constant compression; multiple treatments for fluid reaccumulation are rarely necessary. (SM)

Redefinition of the helical rim in cauliflower-ear surgery.

PubMed

Schonauer, F; La Rusca, I; Pereira, J A; Molea, G

2002-01-01

Cauliflower ear is a serious deformity of the auricle induced by single or repeated injury to the external ear. Few papers deal with surgical techniques for correcting this deformity. We describe the use of ipsilateral excess cartilage to restore the helical rim. Copyright 2002 The British Association of Plastic Surgeons.

Management of pediatric cholesteatoma based on presentations, complications, and outcomes.

PubMed

McGuire, J K; Wasl, H; Harris, T; Copley, G J; Fagan, J J

2016-01-01

To highlight important aspects and paradigms in the management of paediatric cholesteatoma in a developing world setting. A retrospective audit was conducted of paediatric cholesteatomas that underwent tympanomastoid surgery between 2008 and 2012 at the Red Cross War Memorial Children's Hospital in Cape Town. The following was audited: initial presentation; cholesteatoma complications; types of surgery, intraoperative findings and outcomes of surgery in terms of hearing, otorrhoea and recidivism; and the reliability of follow-up and how this might influence the type of surgery. Fifty-seven children aged 2-13 years with 61 cholesteatomas (4 bilateral) were reviewed. Fifty-five mastoidectomies were done; 11% presented with complicated cholesteatoma. Referrals from primary care were significantly delayed (>6 months) in 76%. Canal wall down surgery was done in 71%. Forty-five percent had improved hearing (within 15dB of better hearing ear) and a further 15% had no or only mild hearing loss. Ossicular chain involvement and ossicles encased in inflammatory tissue were associated with poorer hearing outcomes. Sixty-four percent of ears remained dry. Forty-five percent of the canal wall up, and 23% of canal wall down mastoidectomies had recidivism. Twenty-six percent of patients were lost to follow-up. Children are likely to present with advanced cholesteatoma with ossicular chain involvement. The children present with high rates of complications, poor pre-operative hearing and have high recurrence rates post-surgery. Referral from primary health care is delayed. Canal wall down procedures may be appropriate in a setting where patient follow-up is unreliable and access to operating theatre is limited. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

[Otoacoustic emissions of full-term and preterm neonates].

PubMed

Kashiwamura, M; Ohwatari, R; Satoh, N; Kawanami, M; Chida, E; Sakamoto, T; Fukuda, S; Inuyama, Y

1996-01-01

Transiently evoked otoacoustic emission (TEOAE), distortion product otoacoustic emission (DPOAE), and spontaneous otoacoustic emission (SOAE) were measured in 45 full-term neonates (68 ears) and 12 preterm neonates (20 ears) with ILO88 & 92. Measurements were performed in the nursery of the obstetrics ward or NICU (not sound proof room) under natural sleeping condition after nursing. No sedating agent was used. TEOAEs were rated "good response" in 61 (89.7%) of 68 full-term neonate ears. DPOAEs were rated "good response" in 40 (71.4%) of 56 full-term neonate ears. SOAEs were detectable in 25 (62.5%) of 40 full-term neonate ears. Considering the high positive rate of TEOAE in full-term neonates and the easy and noninvasive method of measurement, we concluded that TEOAE is useful for auditory screening in neonates. There was failure to detect TEOAEs in 7 ears and the measurements were all performed within 6 days after birth. Some reports claim that residual amnion in the external auditory canal or the middle ear in the first few days after birth causes slight hearing loss. Thus, we expected that making the measurements more than 7 days after birth might yield higher "good response" rates. We sometimes found that the Total Echo Powers of TEOAEs were reduced by the poor condition of the ear probe. Thus, we must be very careful in regard to this technical problem in order to perform accurate examinations. Because of its lower "good response" rate, DPOAE was not as useful for screening as TEOAE. Because of the movements or respiratory noises of the newborn infants, it was hard to detect reliable DPOAEs, particularly in the low frequency range. On the other hand, because of its frequency specificity, particurally at high frequencies, DPOAE will be useful for detecting the partial hearing impairment such as congenital high-tone hearing impairment. It would be difficult to use SOAE as a clinical test. Because it is not an evoked response, its mechanism of generation is not well understood. We expect that following longitudinal changes in SOAE in neonates may yield some information about it. We measured mainly TEOAE in preterm neonates because we had to complete the measurements as soon as possible. High Total Echo Powers of TEOAEs were recorded in most infants over 38 weeks of PCA (post conceptional age). The earliest case showed reliable TEOAE at 35 weeks PCA. In most cases that could be measured twice on different days, the Total Echo Powers of TEOAE, were higher in the second time. We therefore concluded that TEOAE might serve as an examination for monitoring the maturation of preterm neonate hearing.

Estimation of outer-middle ear transmission using DPOAEs and fractional-order modeling of human middle ear

NASA Astrophysics Data System (ADS)

Naghibolhosseini, Maryam

Our ability to hear depends primarily on sound waves traveling through the outer and middle ear toward the inner ear. Hence, the characteristics of the outer and middle ear affect sound transmission to/from the inner ear. The role of the middle and outer ear in sound transmission is particularly important for otoacoustic emissions (OAEs), which are sound signals generated in a healthy cochlea, and recorded by a sensitive microphone placed in the ear canal. OAEs are used to evaluate the health and function of the cochlea; however, they are also affected by outer and middle ear characteristics. To better assess cochlear health using OAEs, it is critical to quantify the impact of the outer and middle ear on sound transmission. The reported research introduces a noninvasive approach to estimate outer-middle ear transmission using distortion product otoacoustic emissions (DPOAEs). In addition, the role of the outer and middle ear on sound transmission was investigated by developing a physical/mathematical model, which employed fractional-order lumped elements to include the viscoelastic characteristics of biological tissues. Impedance estimations from wideband refectance measurements were used for parameter fitting of the model. The model was validated comparing its estimates of the outer-middle ear sound transmission with those given by DPOAEs. The outer-middle ear transmission by the model was defined as the sum of forward and reverse outer-middle ear transmissions. To estimate the reverse transmission by the model, the probe-microphone impedance was calculated through estimating the Thevenin-equivalent circuit of the probe-microphone. The Thevenin-equivalent circuit was calculated using measurements in a number of test cavities. Such modeling enhances our understanding of the roles of different parts of the outer and middle ear and how they work together to determine their function. In addition, the model would be potentially helpful in diagnosing pathologies of cochlear or middle ear origin.

[Bacteriological evaluation of a procedure for disinfecting the Olympus GIF-D2 panendoscope].

PubMed

Ramírez Ramos, A; Domínguez, N; Makino, R; Barrera, C

1980-01-01

We have performed a total of 107 cultures from three critical areas of an Olympus Panendoscope Model GIF-D2 in order to evaluate bacteriologically cur system of desinfection of this endoscope. Samples were taken from the distal end, external surface and biopsy canal before and after an endoscopic examination was performed. The procedure of desinfection employed was as follows: washing of the distal end, external surface and biopsy canal with Hexaclorophel (Phisohex) diluted 50% with water and a second washing with tap water. In the middle of the study, we added a second washing of the biopsy canal with ten ml. of ether alcohol to allow for better drying. As a result of the present study we observed that in the distal end in 50% of the samples we encountered bacteria. Cultures of the external surface were positive in 20% of samples. The biopsy canal should be washed with ether alcohol to allow for complete drying, because when we did not use this method, Pseudomonas Aeruginosa was isolated. After this modification we did not isolate bacteria. The most frequent types of isolated bacteria were from the normal oropharyngeal flora. From the present study we can conclude that desinfection of the Panendespe with Hexaclorophen gives satisfactory results on the external surface of the endoscope. Biopsy canal requires additional washing with ether alcohol. However, both procedures do not assure a satisfactory desinfection of the distal end.

The path of a click stimulus from ear canal to umbo.

PubMed

Milazzo, Mario; Fallah, Elika; Carapezza, Michael; Kumar, Nina S; Lei, Jason H; Olson, Elizabeth S

2017-03-01

The tympanic membrane (TM) has a key role in transmitting sounds to the inner ear, but a concise description of how the TM performs this function remains elusive. This paper probes TM operation by applying a free field click stimulus to the gerbil ear and exploring the consequent motions of the TM and umbo. Motions of the TM were measured both on radial tracks starting close to the umbo and on a grid distal and adjacent to the umbo. The experimental results confirmed the high fidelity of sound transmission from the ear canal to the umbo. A delay of 5-15 μs was seen in the onset of TM motion between points just adjacent to the umbo and mid-radial points. The TM responded with a ringing motion, with different locations possessing different primary ringing frequencies. A simple analytic model from the literature, treating the TM as a string, was used to explore the experimental results. The click-based experiments and analysis led to the following description of TM operation: A transient sound pressure on the TM causes a transient initial TM motion that is maximal ∼ at the TM's radial midpoints. Mechanical forces generated by this initial prominent TM distortion then pull the umbo inward, leading to a delayed umbo response. The initial TM deformation also gives rise to prolonged mechanical ringing on the TM that does not result in significant umbo motion, likely due to destructive interference from the range of ringing frequencies. Thus, the umbo's response is a high-fidelity representation of the transient stimulus. Because any sound can be considered as a consecutive series of clicks, this description is applicable to any sound stimulus. Copyright © 2017 Elsevier B.V. All rights reserved.

Validity and Reliability of Tympanometric Measures for Pediatric Patients.

ERIC Educational Resources Information Center

Karzon, Roanne G.

1991-01-01

Sensitivity and specificity of static acoustic admittance (SAA) and tympanometric width (TW) were assessed for 116 pediatric patients. A statistically significant change in SAA was observed in immediate repeat measures. No significant change across the two sequential measures was observed for TW, peak pressure, or the estimate of ear canal volume.…

Coupling of FM Systems to Individuals with Unilateral Hearing Loss.

ERIC Educational Resources Information Center

Kopun, Judy G.; And Others

1992-01-01

This study examined the attenuation characteristics of 5 Frequency Modulation system sound delivery options for 25 adults and children (ages 5-13). Degree of ear canal occlusion was a major factor in degree of attenuation. For children with unilateral hearing impairments, the most acoustically appropriate option was the tube-fitting. (Author/JDD)

Inner ear contribution to bone conduction hearing in the human.

PubMed

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. Copyright © 2014 Elsevier B.V. All rights reserved.

Local cochlear damage reduces local nonlinearity and decreases generator-type cochlear emissions while increasing reflector-type emissions.

PubMed

Dong, Wei; Olson, Elizabeth S

2010-03-01

Distortion product otoacoustic emissions (DPOAEs) originate in cochlear nonlinearity and emerge into the ear canal as an apparent sum of emission types, one of which (generator) travels directly out and the other (reflector) travels out following linear reflection. The present study explores intracochlear sources of DPOAEs via simultaneous ear canal and intracochlear pressure measurements in gerbils. A locally damaged cochlea was produced with reduced local intracochlear nonlinearity and significant elevation of the compound action potential thresholds at frequencies represented within the damaged region. In the DPOAE the comparison of healthy to locally damaged cochleae showed the following: (1) In the broad frequency region corresponding to the locally damaged best frequency, DPOAEs evoked by wider f(2)/f(1) stimuli decreased, consistent with the reduction in local nonlinearity. (2) DPOAEs evoked by narrow f(2)/f(1) stimuli often had a bimodal change, decreasing in a lower frequency band and increasing in a band just adjacent and higher, and the DPOAE phase-vs-frequency slope steepened. These changes confirm the complex nature of the DPOAE.

Caloric Analysis of Patients with Benign Paroxysmal Positional Vertigo.

PubMed

Yetişer, Sertaç; İnce, Dilay

2017-12-01

The aim of this study is to compare nystagmus characteristics after caloric irrigation in patients with lateral canal (LC) and posterior canal (PC) benign paroxysmal positional vertigo (BPPV) and to analyze the role of symptom duration. A prospective study was conducted in 65 patients with BPPV (20 LC and 45 PC) who were subjected to caloric testing. Average slow-phase velocity and nystagmus duration were analyzed. Caloric hypo-excitability was 20.4%. It was more evident in patients with apogeotropic-type LC-BPPV. The comparison of average slow-phase velocity of the nystagmus and nystagmus duration between selected types of BPPV for pathologic, non-pathologic, and the control ears after warm and cold stimulation was not statistically significant (p>0.05). No correlation was found between caloric results and symptom duration (p>0.05). Some patients presented caloric hypo-excitability. Reliability of caloric testing to differentiate the ear with normal and abnormal vestibular function in different types of BPPV was low. No difference was found in the analysis of the impact of symptom duration. Caloric testing is not an ideal tool to study BPPV.

Root canal morphology of primary molars: a micro-computed tomography study.

PubMed

Fumes, A C; Sousa-Neto, M D; Leoni, G B; Versiani, M A; da Silva, L A B; da Silva, R A B; Consolaro, A

2014-10-01

This was to investigate the root canal morphology of primary molar teeth using micro-computed tomography. Primary maxillary (n = 20) and mandibular (n = 20) molars were scanned at a resolution of 16.7 μm and analysed regarding the number, location, volume, area, structured model index (SMI), area, roundness, diameters, and length of canals, as well as the thickness of dentine in the apical third. Data were statistically compared by using paired-sample t test, independent sample t test, and one-way analysis of variance with significance level set as 5%. Overall, no statistical differences were found between the canals with respect to length, SMI, dentine thickness, area, roundness, and diameter (p > 0.05). A double canal system was observed in the mesial and mesio-buccal roots of the mandibular and maxillary molars, respectively. The thickness in the internal aspect of the roots was lower than in the external aspect. Cross-sectional evaluation of the roots in the apical third showed flat-shaped canals in the mandibular molars and ribbon- and oval-shaped canals in the maxillary molars. External and internal anatomy of the primary first molars closely resemble the primary second molars. The reported data may help clinicians to obtain a thorough understanding of the morphological variations of root canals in primary molars to overcome problems related to shaping and cleaning procedures, allowing appropriate management strategies for root canal treatment.

Long-term consequences of Sox9 depletion on inner ear development

PubMed Central

Park, Byung-Yong; Saint-Jeannet, Jean-Pierre

2010-01-01

The transcription factor Sox9 has been implicated in inner ear formation in several species. To investigate the long-term consequences of Sox9 depletion on inner ear development we analyzed the inner ear architecture of Sox9-depleted Xenopus tadpoles generated by injection of increasing amounts of Sox9 morpholino antisense oligonucleotides. We found that Sox9-depletion resulted in major defects in the development of vestibular structures, semicircular canals and utricle, while the ventrally located saccule was less severely affected in these embryos. Consistent with this phenotype we observed a specific loss of the dorsal expression of Wnt3a expression in the otic vesicle of Sox9 morphants, associated with an increase in cell death and a reduction in cell proliferation in the region of the presumptive otic epithelium. We propose that in addition to its early role in placode specification, Sox9 is also required for the maintenance of progenitors in the otic epithelium. PMID:20201105

A systematic review on external ear melanoma.

PubMed

Toia, Francesca; Garbo, Giuseppe; Tripoli, Massimiliano; Rinaldi, Gaetana; Moschella, Francesco; Cordova, Adriana

2015-07-01

External ear melanoma accounts for only 1% of all cutaneous melanomas, and data on its optimal management and prognosis are limited. We aim to review the literature on external ear melanoma to guide surgeons in the treatment of this uncommon and peculiar pathology. A systematic review of English language studies on ear melanoma published from 1993 to 2013 was performed using the PubMed electronic database. Data on epidemiology, oncological treatment (tumor resection and regional lymph nodes management), and reconstruction were extrapolated from selected papers. The total number of patients was 858 (30 studies). The helix was the most common location (57%); superficial spreading melanoma was the most common histopathological subtype (41%). The mean Breslow thickness was 2.01 mm, with 88% of stage I-II patients. Sentinel lymph node biopsy was performed in 45% of patients, with 8% of positive nodes. Available data on its prognosis are fragmentary and contrasting, but the Breslow thickness appears to be the main prognostic factor. There is a tendency towards reduced resection margins and preservation of the underlying perichondrium and cartilage. Local flaps are the most popular reconstructive option. To the best of our knowledge, this systematic review presents the largest data series on external ear melanoma. There is no general agreement on its surgical management, but a favorable prognosis seems to justify the tendency towards conservative treatments. Copyright © 2015 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

External ear anomalies and hearing impairment in Noonan Syndrome.

PubMed

van Trier, Dorothée C; van Nierop, Josephine; Draaisma, Jos M Th; van der Burgt, Ineke; Kunst, Henricus; Croonen, Ellen A; Admiraal, Ronald J C

2015-06-01

This is the first cohort in which hearing impairment and external ear anomalies in Noonan Syndrome are described extensively. Retrospective analysis of the otorhinolaryngological and clinical genetic data from 97 Noonan Syndrome (NS) patients. Forty-four NS patients were seen by an otorhinolaryngologist for the analysis of hearing impairment. In our cohort 80 of the 97 patients were genetically tested. In 71 of these mutations were found: in 48 patients a mutation in PTPN11, in 10 patients in SOS1, in 5 patients in SHOC2, in 5 patients in RAF1, in 1 patient in MAP2K2, in 1 patient in KRAS and in 1 patient in A2ML1. External ear anomalies were reported in 75 NS patients (77%). In 69 patients the ears were low-set, 28 patients had posteriorly rotated ears, 14 patients showed protruding ears and 18 had thickened helices. Hearing impairment was detected in 34 NS patients. Nine patients had sensorineural hearing impairment, two a permanent conductive hearing impairment, two other patients had mixed hearing impairment and 20 patients had conductive hearing impairment in the past, caused by otitis media with effusion. Their temporary conductive hearing impairment resolved between the ages of 2 and 18 years. Sensorineural hearing impairment varied between mild high-frequency hearing impairment and profound (uni- and bilateral) hearing impairment and was progressive in three patients. Four NS patients received cochlear implants for their severe sensorineural hearing impairment. The cohort is small for genotype-phenotype correlations, but sensorineural hearing impairment, especially the bilateral severe hearing impairment, was only seen in patients with a PTPN11 mutation. NS is characterized by dysmorphic external ear anomalies and both sensorineural and conductive hearing impairment. Audiological examinations are recommended in all patients with Noonan Syndrome. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Encoding of speech sounds at auditory brainstem level in good and poor hearing aid performers.

PubMed

Shetty, Hemanth Narayan; Puttabasappa, Manjula

Hearing aids are prescribed to alleviate loss of audibility. It has been reported that about 31% of hearing aid users reject their own hearing aid because of annoyance towards background noise. The reason for dissatisfaction can be located anywhere from the hearing aid microphone till the integrity of neurons along the auditory pathway. To measure spectra from the output of hearing aid at the ear canal level and frequency following response recorded at the auditory brainstem from individuals with hearing impairment. A total of sixty participants having moderate sensorineural hearing impairment with age range from 15 to 65 years were involved. Each participant was classified as either Good or Poor Hearing aid Performers based on acceptable noise level measure. Stimuli /da/ and /si/ were presented through loudspeaker at 65dB SPL. At the ear canal, the spectra were measured in the unaided and aided conditions. At auditory brainstem, frequency following response were recorded to the same stimuli from the participants. Spectrum measured in each condition at ear canal was same in good hearing aid performers and poor hearing aid performers. At brainstem level, better F 0 encoding; F 0 and F 1 energies were significantly higher in good hearing aid performers than in poor hearing aid performers. Though the hearing aid spectra were almost same between good hearing aid performers and poor hearing aid performers, subtle physiological variations exist at the auditory brainstem. The result of the present study suggests that neural encoding of speech sound at the brainstem level might be mediated distinctly in good hearing aid performers from that of poor hearing aid performers. Thus, it can be inferred that subtle physiological changes are evident at the auditory brainstem in a person who is willing to accept noise from those who are not willing to accept noise. Copyright © 2016 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

The Contribution of Head Movement to the Externalization and Internalization of Sounds

PubMed Central

Brimijoin, W. Owen; Boyd, Alan W.; Akeroyd, Michael A.

2013-01-01

Background When stimuli are presented over headphones, they are typically perceived as internalized; i.e., they appear to emanate from inside the head. Sounds presented in the free-field tend to be externalized, i.e., perceived to be emanating from a source in the world. This phenomenon is frequently attributed to reverberation and to the spectral characteristics of the sounds: those sounds whose spectrum and reverberation matches that of free-field signals arriving at the ear canal tend to be more frequently externalized. Another factor, however, is that the virtual location of signals presented over headphones moves in perfect concert with any movements of the head, whereas the location of free-field signals moves in opposition to head movements. The effects of head movement have not been systematically disentangled from reverberation and/or spectral cues, so we measured the degree to which movements contribute to externalization. Methodology/Principal Findings We performed two experiments: 1) Using motion tracking and free-field loudspeaker presentation, we presented signals that moved in their spatial location to match listeners’ head movements. 2) Using motion tracking and binaural room impulse responses, we presented filtered signals over headphones that appeared to remain static relative to the world. The results from experiment 1 showed that free-field signals from the front that move with the head are less likely to be externalized (23%) than those that remain fixed (63%). Experiment 2 showed that virtual signals whose position was fixed relative to the world are more likely to be externalized (65%) than those fixed relative to the head (20%), regardless of the fidelity of the individual impulse responses. Conclusions/Significance Head movements play a significant role in the externalization of sound sources. These findings imply tight integration between binaural cues and self motion cues and underscore the importance of self motion for spatial auditory perception. PMID:24312677

Predicting round window niche visibility via the facial recess using high-resolution computed tomography.

PubMed

Kashio, Akinori; Sakamoto, Takashi; Karino, Shotaro; Kakigi, Akinobu; Iwasaki, Shinichi; Yamasoba, Tatsuya

2015-01-01

To predict round window niche (RWN) visibility using high-resolution computed tomography (HRCT). Case series with chart review. Academic tertiary care center. We retrospectively reviewed 70 cochlear implant ears that underwent presurgical axial HRCT with a surgical video recorder. The visibility of the RWN was classified into three types: 17 as invisible or nearly invisible, 22 as partially visible, and 31 as fully visible. Next, we measured the following three radiologic parameters: 1) the angle of the external auditory canal (EAC) relative to the cochlear basal turn, 2) the width of the facial recess, and 3) the relative location of the facial nerve (FN) to the cochlear basal turn. These were compared with the RWN visibility. Subsequently, to predict the RWN visibility, a line was created parallel to the EAC line and along the anterior lateral FN. The location of the line relative to the round window membrane was compared with the RWN view. In cases that had poor RWN visibility, the angle of the posterior canal wall portion of the EAC relative to the cochlear basal turn was significantly smaller and the location of the FN to the cochlear basal turn was closer. The location of the prediction line to the round window membrane highly predicted the RWN view during the surgery. The RWN visibility and the preoperative HRCT findings showed a high correlation. Drawing the prediction line is a simple and useful way for preoperatively predicting the RWN visibility in cochlear implant surgery.

Does canal wall down mastoidectomy benefit syndromic children with congenital aural stenosis?

PubMed

Sjogren, Phayvanh P; Gurgel, Richard K; Park, Albert H

2016-11-01

To determine whether a canal wall down mastoidectomy can provide long-term benefit for children with aural stenosis. Retrospective case series of children with congenital aural stenosis having undergone a canal wall down mastoidectomy over a twelve-year period at a tertiary children's hospital. Data from thirteen children who underwent a total of twenty canal wall down mastoidectomies for aural stenosis were reviewed. The mean age at surgery was 7.1 years (range, 3.3-12.3 years). All patients had genetic syndromes including Trisomy 21 (n = 7), Trisomy 21 and Pierre Robin sequence (n = 1), Angelmann (n = 1), Cri-du-chat (n = 1), Branchio-oto-renal syndrome (n = 1), Spina bifida (n = 1) and Nager syndrome (n = 1). Seven (54%) children underwent bilateral canal wall down mastoidectomies. All thirteen ears that could not be visualized preoperatively had improved ease of office examination following surgery. Only one patient required revision surgery and all canals were patent at the last clinic visit. The mean follow-up was 4.9 years. There were no cases of facial nerve injury or cerebrospinal fluid leak. Syndromic children with congenital aural stenosis with poorly pneumatized mastoids may benefit from canal wall down mastoidectomy to improve ease of office examinations. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Acoustic Transmission Characteristics of a Eustachian Tube Volitionally Opened in Two Living Subjects.

PubMed

Amoako-Tuffour, Yaw; Jufas, Nicholas; Quach, Jack; Le, Lisa; Earle, Guy; Kotiya, Akhilesh A; Bance, Manohar

2016-09-01

To assess the acoustic transmission characteristics of the Eustachian tube (ET) in living subjects in verified patent and closed ET states to facilitate the detection and quantification of ET function using acoustic measures such as sonotubometry. The two subjects in this study had no history of ear disease nor previous ear surgery and were capable of volitionally opening and closing their ET. Tympanometry and otologic examinations were used to confirm ET patent and closed states by observing tympanic membrane movement with respiration and by acoustic immitance measurements during forced respiration. A series of 500-ms long chirps containing frequencies from 100 Hz to 10 kHz were introduced into the nasal cavity during both ET states and recorded by microphones in both the contralateral naris and external auditory canal. Acoustic energy transmission through the ET across the 0.1 to 10 kHz frequency range in the closed state versus the patent state. An increase in acoustic energy transmission occurs across the frequencies of 1 to 4 kHz between the closed and patent ET states, particularly in frequencies below 2.5 kHz. Results support sonotubometry as a potential diagnostic tool for ET dysfunction. Acoustic differences between the ET states manifest as a general increase in transmitted signal amplitude. Characterizing the acoustic properties in the verified patent and closed ET states allows investigators to more reliably interpret sonotubometric tests of ET function.

Cauliflower ear dissection.

PubMed

Fujiwara, Masao; Suzuki, Ayano; Nagata, Takeshi; Fukamizu, Hidekazu

2011-11-01

Cauliflower ear (CE) is caused by repeated direct trauma to the external ear. Surgical correction of an established CE is one of the most challenging problems in ear reconstruction. However, no reports have clarified the dissection of an established CE in detail. In this report, the dissection of a CE is described based on macroscopic, microscopic and imaging features. Copyright © 2011 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Magnetically driven middle ear ossicles for optical measurement of vibrations in an ear with opened tympanic membrane

NASA Astrophysics Data System (ADS)

Peacock, J.; von Unge, M.; Dirckx, J.

2013-12-01

Vibrations of the middle ear ossicles are easily measured by means of laser vibrometry. However, laser vibrometry requires free visual access to the object under investigation, and acquiring free visual access to the ossicles through the ear canal requires the removal of the tympanic membrane (TM), with the result that the ossicles can no longer be stimulated acoustically. To overcome this, we devised a new setup in which the ossicles can be driven magnetically. After measuring the response of the TM to an acoustic signal, we then remove it and attach a small magnet to the exposed manubrium (a part of the most lateral auditory ossicle, the malleus, which is normally attached to the TM). An electromagnetic excitation coil is then used to drive the magnet, and the output to the coil adjusted until the vibration of the manubrium, as measured by the vibrometer, matches that measured in response to the acoustic signal. Such a setup may have uses in research on middle ear mechanics, such as the measurement of nonlinearities in their response, as well as applications in the diagnosis of middle ear conditions such as the fixation of the ossicles by otosclerosis or in chronic otitis media. We describe our setup and discuss the viability of our method and its future clinical potential by presenting some measurements on an artificially fixated ear.

Gerbil middle-ear sound transmission from 100 Hz to 60 kHz1

PubMed Central

Ravicz, Michael E.; Cooper, Nigel P.; Rosowski, John J.

2008-01-01

Middle-ear sound transmission was evaluated as the middle-ear transfer admittance HMY (the ratio of stapes velocity to ear-canal sound pressure near the umbo) in gerbils during closed-field sound stimulation at frequencies from 0.1 to 60 kHz, a range that spans the gerbil’s audiometric range. Similar measurements were performed in two laboratories. The HMY magnitude (a) increased with frequency below 1 kHz, (b) remained approximately constant with frequency from 5 to 35 kHz, and (c) decreased substantially from 35 to 50 kHz. The HMY phase increased linearly with frequency from 5 to 35 kHz, consistent with a 20–29 μs delay, and flattened at higher frequencies. Measurements from different directions showed that stapes motion is predominantly pistonlike except in a narrow frequency band around 10 kHz. Cochlear input impedance was estimated from HMY and previously-measured cochlear sound pressure. Results do not support the idea that the middle ear is a lossless matched transmission line. Results support the ideas that (1) middle-ear transmission is consistent with a mechanical transmission line or multiresonant network between 5 and 35 kHz and decreases at higher frequencies, (2) stapes motion is pistonlike over most of the gerbil auditory range, and (3) middle-ear transmission properties are a determinant of the audiogram. PMID:18646983

Visualization of human inner ear anatomy with high-resolution MR imaging at 7T: initial clinical assessment.

PubMed

van der Jagt, M A; Brink, W M; Versluis, M J; Steens, S C A; Briaire, J J; Webb, A G; Frijns, J H M; Verbist, B M

2015-02-01

In many centers, MR imaging of the inner ear and auditory pathway performed on 1.5T or 3T systems is part of the preoperative work-up of cochlear implants. We investigated the applicability of clinical inner ear MR imaging at 7T and compared the visibility of inner ear structures and nerves within the internal auditory canal with images acquired at 3T. Thirteen patients with sensorineural hearing loss eligible for cochlear implantation underwent examinations on 3T and 7T scanners. Two experienced head and neck radiologists evaluated the 52 inner ear datasets. Twenty-four anatomic structures of the inner ear and 1 overall score for image quality were assessed by using a 4-point grading scale for the degree of visibility. The visibility of 11 of the 24 anatomic structures was rated higher on the 7T images. There was no significant difference in the visibility of 13 anatomic structures and the overall quality rating. A higher incidence of artifacts was observed in the 7T images. The gain in SNR at 7T yielded a more detailed visualization of many anatomic structures, especially delicate ones, despite the challenges accompanying MR imaging at a high magnetic field. © 2015 by American Journal of Neuroradiology.

Extended lateral thoracic fasciocutaneous biosynthetic flap for reconstruction of full-thickness partial external ear defects: an experimental study.

PubMed

Kuvat, Samet Vasfi; Taşkın, Ümit; Yücebaş, Kadir; Tansuker, Hasan Deniz; Oktay, Mehmet Faruk; Kozanoğlu, Erol; Aydın, Salih

2017-01-01

External ear reconstruction is a controversial topic in reconstructive plastic surgery. Here, we prepared a pedicled biosynthetic flap for full-thickness, partial ear defects in rabbits. We operated on six adult female New Zealand rabbits weighing 3-4 kg. The dimensions of the lateral thoracic fasciocutaneous flap were 7 × 6 cm. The flap was elevated based on one of the bilaterally located internal thoracic arteries, which were dissected proximally. The pedicled flap was folded in two, and polypropylene mesh was sandwiched in the middle. The flap was adapted to a defect of 3.5 × 3 cm in diameter. In fact, the defect was created before elevation of the flap. Rabbits were followed up for 4 weeks, at the end of which they were killed and their ears were evaluated histopathologically. The survival rate of the rabbits was 100 %. All pedicled biosynthetic flaps were viable, but one showed partial (20 %) necrosis (1/6) and one was partially detached (1/6). Macroscopic (color, thickness, texture) and histological (polymorphonuclear leukocyte invasion in the skin, subcutaneous tissue, and at the junction between the polypropylene mesh and the flap) features of the flap were compared to the ipsilateral ear. A new technique was developed for partial external ear reconstruction with sufficient inner skeletal support and outer skin lining. Level of evidence Level NA.

Reconstruction following traumatic partial amputation of the ear.

PubMed

Pearl, Robert A; Sabbagh, Walid

2011-02-01

Reconstruction following traumatic amputation of the external ear remains a unique challenge to the plastic surgeon. The authors report a series of ear reconstructions with autologous costal cartilage in patients following traumatic partial amputation of the ear. Technical points regarding the carving of the cartilage framework and methods of skin coverage are discussed. Fifty partial ear reconstructions with autologous costal cartilage were performed over a 4-year period. All patients had suffered previous traumatic amputation of part of the external auricle due to bite injuries (n = 36), road traffic accidents (n = 6), burns (n = 5), or torture (n = 3). A two-stage technique of reconstruction with autologous cartilage graft was used based on Nagata's adaptations of Brent's original technique. In nine cases, skin shortage or extensive scarring required preoperative tissue expansion (n = 4) or a temporoparietal fascial flap (n = 5) to provide adequate coverage of the cartilage framework. Forty-seven patients had a successful surgical outcome without complication. Two patients developed small areas of skin necrosis resulting in exposure of the cartilage framework. These healed with conservative management with minor loss of definition. One case of wound infection resulted in significant loss of definition of the construct, which required a further surgical procedure with additional costal cartilage graft. Reconstruction of the external ear with autologous costal cartilage following traumatic amputation can produce high-quality auricles consistently and is becoming the treatment of choice for such injuries, given access to a specialist center with exposure to a high volume of cases.

Nodular fasciitis of the external auditory canal in six Egyptian children.

PubMed

Abdel-Aziz, Mosaad; Khattab, Hany; El-bosraty, Hussam; El-hoshy, Hassan; Hesham, Ahmed; Al-taweel, Hayam W

2008-05-01

Nodular fasciitis of external auditory canal may mimic a malignant tumor due to its progressive course, so it was the aim of this study to focus on a new etiology for aural masses to avoid unnecessary aggressive treatment. Retrospective study on six children presented with aural masses that were diagnosed pathologically to have nodular fasciitis. Presentation of the cases clinically, radiologically and pathologically was carried out. Surgical excision of the lesions was done through the external canal with follow up of the cases for 1 year. Recurrence was detected in two cases, one after 2 months and the other after 4 months. Re-excision was carried out without recurrence till the end of the follow up period. Proper diagnosis of this lesion is mandatory to avoid aggressive treatment (radical surgery and/or radiotherapy) as the disease has favorable prognosis with local excision.

Automated Speech Intelligibility System for Head-Borne Personal Protective Equipment: Proof of Concept

DTIC Science & Technology

2008-04-01

selected as the listener headform for this effort. The HATS has binaural sound quality microphones inserted into the ear canals and rubber pinnae that...Blank 16 APPENDIX - WORD LISTS AND SUBJECT RESPONSES MRT Set 1 (spoken word is in bold type) kick, lick, sick, tick, wick, pick neat, beat , seat, meat

Synchronization of spontaneous otoacoustic emissions in the tokay gecko

NASA Astrophysics Data System (ADS)

Roongthumskul, Yuttana; Hudspeth, A. J.

2018-05-01

Spontaneous otoacoustic emissions (SOAEs) are a universal feature of all classes of tetrapods. Although the generation mechanism of SOAEs are incompletely understood, these emissions are undoubtedly associated with the active process of the inner ear. In most lizards, unlike mammals and amphibians, robust SOAEs can ordinarily be detected from both ears. In this work, we investigated the interactions between emissions recorded simultaneously from the two ears of tokay geckos. We found that the frequency spectra of SOAEs from both ears of an individual animal are partially correlated: the peaks of several emissions occur at identical frequencies. To investigate the underlying mechanisms of these identical-frequency SOAEs, we perturbed the emissions from one or both ears by manipulating the pressure in the ear canals or by decreasing the local temperature in the vicinity of one inner ear. Suppression of SOAEs due to large positive pressures revealed that some identical-frequency emissions were generated unilaterally, whereas others were contributed by both ears at identical or slightly different frequencies. These bilaterally generated SOAEs became desynchronized as their frequency detuning grew sufficiently large, a phenomenon consistent with the synchronization of two active oscillators. Finally, we found that manipulations of the volume of the oral cavity or altering the impedance of the tympanum strongly affected the synchronization of SOAEs. These findings agreed with previous studies suggesting that the tokay gecko, like other lizards, exhibits strong acoustic coupling between its tympani through the oral cavity.

The Modified Rambo Transcanal Approach for Cochlear Implantation in CHARGE Syndrome.

PubMed

Wick, Cameron C; Moore, Amy M; Killeen, Daniel E; Isaacson, Brandon

2017-10-01

CHARGE syndrome is associated with a variety of temporal bone anomalies and deafness. The lack of surgical landmarks and facial nerve irregularities make cochlear implantation in this population a challenging endeavor. This study aims to describe a safe and efficacious transcanal approach for cochlear implantation that obviates the need to perform a mastoidectomy and facial recess. Three children with profound hearing loss secondary to CHARGE syndrome. Transcanal cochlear implantation with closure of the ear canal via a modified Rambo meatoplasty. Retrospective chart review of temporal bone anomalies associated with CHARGE syndrome, technical nuances of this transcanal approach, and cochlear implant outcomes. The mean patient age was 2.5 years (range 1.5-3.8 yr). Two were male and two were left ears. All patients had a hypoplastic mastoid, semicircular canal aplasia, and had some degree of cochlear dysplasia. A full cochlear implant insertion was achieved in all cases, even in the presence of grossly abnormal middle ear and facial nerve anatomy. There were no intraoperative or postoperative complications. The mean follow-up was 12.4 months (range, 3.9-25.2 mo). All three patients use their device daily. Their guardians report improved vocalization and environmental awareness. The modified Rambo transcanal approach provides a safe corridor for cochlear implantation in patients with CHARGE syndrome. This approach minimizes the anatomical variations associated with the syndrome and may reduce the risk of electrode extrusion. Implant outcomes in this patient population remain highly variable based on the patient's global cognitive capacity.

Inner ear dysfunction in caspase-3 deficient mice

PubMed Central

2011-01-01

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 < 0.05) compared to Casp3+/- mice and Casp3+/+ mice at 3 months of age. In DPOAE testing, distortion product 2F1-F2 was significantly decreased (P < 0.05) in 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. PMID:21988729

Internal carotid arterial canal size and scaling in Euarchonta: Re-assessing implications for arterial patency and phylogenetic relationships in early fossil primates.

PubMed

Boyer, Doug M; Kirk, E Christopher; Silcox, Mary T; Gunnell, Gregg F; Gilbert, Christopher C; Yapuncich, Gabriel S; Allen, Kari L; Welch, Emma; Bloch, Jonathan I; Gonzales, Lauren A; Kay, Richard F; Seiffert, Erik R

2016-08-01

Primate species typically differ from other mammals in having bony canals that enclose the branches of the internal carotid artery (ICA) as they pass through the middle ear. The presence and relative size of these canals varies among major primate clades. As a result, differences in the anatomy of the canals for the promontorial and stapedial branches of the ICA have been cited as evidence of either haplorhine or strepsirrhine affinities among otherwise enigmatic early fossil euprimates. Here we use micro X-ray computed tomography to compile the largest quantitative dataset on ICA canal sizes. The data suggest greater variation of the ICA canals within some groups than has been previously appreciated. For example, Lepilemur and Avahi differ from most other lemuriforms in having a larger promontorial canal than stapedial canal. Furthermore, various lemurids are intraspecifically variable in relative canal size, with the promontorial canal being larger than the stapedial canal in some individuals but not others. In species where the promontorial artery supplies the brain with blood, the size of the promontorial canal is significantly correlated with endocranial volume (ECV). Among species with alternate routes of encephalic blood supply, the promontorial canal is highly reduced relative to ECV, and correlated with both ECV and cranium size. Ancestral state reconstructions incorporating data from fossils suggest that the last common ancestor of living primates had promontorial and stapedial canals that were similar to each other in size and large relative to ECV. We conclude that the plesiomorphic condition for crown primates is to have a patent promontorial artery supplying the brain and a patent stapedial artery for various non-encephalic structures. This inferred ancestral condition is exhibited by treeshrews and most early fossil euprimates, while extant primates exhibit reduction in one canal or another. The only early fossils deviating from this plesiomorphic condition are Adapis parisiensis with a reduced promontorial canal, and Rooneyia and Mahgarita with reduced stapedial canals. Copyright © 2016 Elsevier Ltd. All rights reserved.

The role of pars flaccida in human middle ear sound transmission.

PubMed

Aritomo, H; Goode, R L; Gonzalez, J

1988-04-01

The role of the pars flaccida in middle ear sound transmission was studied with the use of twelve otoscopically normal, fresh, human temporal bones. Peak-to-peak umbo displacement in response to a constant sound pressure level at the tympanic membrane was measured with a noncontacting video measuring system capable of repeatable measurements down to 0.2 micron. Measurements were made before and after pars flaccida modifications at 18 frequencies between 100 and 4000 Hz. Four pars flaccida modifications were studied: (1) acoustic insulation of the pars flaccida to the ear canal with a silicone rubber baffle, (2) stiffening the pars flaccida with cyanoacrylate cement, (3) decreasing the tension of the pars flaccida with a nonperforating incision, and (4) perforation of the pars flaccida. All of the modifications (except the perforation) had a minimal effect on umbo displacement; this seems to imply that the pars flaccida has a minor acoustic role in human beings.

A cochlear-bone wave can yield a hearing sensation as well as otoacoustic emission

PubMed Central

Tchumatchenko, Tatjana; Reichenbach, Tobias

2014-01-01

A hearing sensation arises when the elastic basilar membrane inside the cochlea vibrates. The basilar membrane is typically set into motion through airborne sound that displaces the middle ear and induces a pressure difference across the membrane. A second, alternative pathway exists, however: stimulation of the cochlear bone vibrates the basilar membrane as well. This pathway, referred to as bone conduction, is increasingly used in headphones that bypass the ear canal and the middle ear. Furthermore, otoacoustic emissions, sounds generated inside the cochlea and emitted therefrom, may not involve the usual wave on the basilar membrane, suggesting that additional cochlear structures are involved in their propagation. Here we describe a novel propagation mode within the cochlea that emerges through deformation of the cochlear bone. Through a mathematical and computational approach we demonstrate that this propagation mode can explain bone conduction as well as numerous properties of otoacoustic emissions. PMID:24954736

Comparative study of aural microflora in healthy cats, allergic cats and cats with systemic disease.

PubMed

Pressanti, Charline; Drouet, Clémence; Cadiergues, Marie-Christine

2014-12-01

Twenty healthy cats (group 1) with clinically normal ears, 15 cats with systemic disease (group 2) and 15 allergic cats (group 3) were included in a prospective study. The experimental unit was the ear. A clinical score was established for each ear canal after otoscopic examination. Microbial population was assessed on cytological examination of smears performed with the cotton-tipped applicator smear technique. Fungal population was significantly more prominent in allergic cats (P <0.001) and in diseased cats compared with healthy cats (P <0.02). Bacterial population was significantly higher in allergic cats than in healthy cats (P <0.001) and cats suffering from systemic disease (P <0.001). Bacterial overgrowth was also higher in cats with systemic disease than healthy cats. In cats from group 2, only fungal overgrowth was associated with otitis severity. In group 3, only bacterial overgrowth was associated with otitis severity. © ISFM and AAFP 2014.

A simplified technique of orthograde MTA obturation on the elected canals of posterior teeth: Two case reports.

PubMed

Wahengbam, Brucelee; Wahengbam, Pragya; Tikku, Aseem Prakash

2014-01-01

This article suggests a simplified technique of orthograde MTA obturation in less accessible canal(s) of posteriors teeth without using costly ultrasonics or specialised carrier. Essentially few finger pluggers, absorbent points and a simple canal projection method were used. The orifice(s) of the elected canal(s) to be obturated with MTA were projected onto the external occlusal surface for easy delivery and predictive instrumentation. The idea was based on 'easy access', 'working one canal with one mix at one time', 'thorough condensation' and 'removal of excess moisture'. In case I, palatal canal of tooth no. 2 with gross apical perforation and suspected VRF was obturated with MTA. And in Case II, tooth no. 19 presented with incomplete furcal fracture extending into the canal was obturated with MTA in all 3 canals unitarily. Dense homogenous MTA obturation was achieved and both cases healed uneventfully.

Design and preliminary testing of a novel skin expander for total ear reconstruction in a rabbit model.

PubMed

Xiong, Wu; Yan, Yu; Hu, Feng; Liu, Can; Wang, Shaohua; Chen, Jia; Wang, Xueqi; Zhou, Jianda

2016-01-01

Ear reconstruction is one of the most complicated and challenging techniques in plastic surgery because of the histologic and anatomic properties of the ear. Success depends on fitting the auriform cartilage scaffold into the overlying skin, but current approaches can just give results that are not lifelike and can lead to complications. A novel double-capsule, double-valve plastic ear expander was designed and implanted subcutaneously on either side of the dorsum of six New Zealand white rabbits (two expanders per rabbit). The outer capsule was expanded by injecting approximately 120 mL of physiological saline, then withdrawing the liquid on two occasions. Next, the ear-shaped inner capsule was filled with high-hardness plaster, and the external capsule was emptied such that the expanded skin flap and external capsule responded to the negative pressure and closed over the ear-shaped inner capsule. As a result, the skin flap adopted an ear shape. The ear expander was left in place for 4 wk, removed with the help of a mini-incision, and stripped of its fibrous capsule. To simulate human ear reconstruction, the expander was replaced with an auriform silicone prosthesis, and the effects of auricular reconstruction were observed dynamically. All 12 skin flaps maintained abundant blood supply, created a clear outline of the ear framework, and produced a lifelike result. No complications were observed during the 4-wk observation period. The expanded skin flaps described here can mold to the desired contours and appear lifelike, as well as maintain abundant blood supply. This may provide a simpler approach to total ear reconstruction that reduces risk of complications. Copyright © 2016 Elsevier Inc. All rights reserved.

Comparison of user volume control settings for portable music players with three earphone configurations in quiet and noisy environments.

PubMed

Henry, Paula; Foots, Ashley

2012-03-01

Listening to music is one of the most common forms of recreational noise exposure. Previous investigators have demonstrated that maximum output levels from headphones can exceed safe levels. Although preferred listening levels (PLL) in quiet environments may be at acceptable levels, the addition of background noise will add to the overall noise exposure of a listener. Use of listening devices that block out some of the background noise would potentially allow listeners to select lower PLLs for their music. Although one solution is in-the-ear earphones, an alternative solution is the use of earmuffs in conjunction with earbuds. There were two objectives to this experiment. The first was to determine if an alternative to in-the-ear earphones for noise attenuation (the addition of earmuffs to earbuds) would allow for lower PLLs through a portable media player (PMP) than earbuds. The second was to determine if a surrounding background noise would yield different PLLs than a directional noise source. This was an experimental study. Twenty-four adults with normal hearing. PLLs were measured for three earphone configurations in three listening conditions. The earphone configurations included earbuds, canal earphones, and earbuds in combination with hearing protection devices (HPDs). The listening conditions included quiet, noise from one loudspeaker, and noise from four surrounding loudspeakers. Participants listened in each noise and earphone combination for as long as they needed to determine their PLL for that condition. Once the participant determined their PLL, investigators made a 5 sec recording of the music through a probe tube microphone. The average PLLs in each noise and earphone combination were used as the dependent variable. Ear canal level PLLs were converted to free-field equivalents to compare to noise exposure standards and previously published data. The average PLL as measured in the ear canal was 74 dBA in the quiet conditions and 84 dBA in the noise conditions. Paired comparisons of the PLL in the presence of background noise for each pair of earphone configurations indicated significant differences for each comparison. An inverse relationship was observed between attenuation and PLL whereby the greater the attenuation, the lower the PLL. A comparison of the single noise source condition versus the surrounding noise condition did not result in a significant effect. The present work suggests that earphones that take advantage of noise attenuation can reduce the level at which listeners set music in the presence of background noise. An alternative to in-the-ear earphones for noise attenuation is the addition of earmuffs to earbuds. American Academy of Audiology.

3-Rooted Maxillary First Premolars: An Ex Vivo Study of External and Internal Morphologies.

PubMed

Beltes, Panagiotis; Kalaitzoglou, Maria-Elpida; Kantilieraki, Eleni; Beltes, Charalampos; Angelopoulos, Christos

2017-08-01

This study aimed to analyze the external and internal morphologies of 3-rooted maxillary first premolars using cone-beam computed tomographic (CBCT) imaging. Fifty-six three-rooted maxillary first premolars were imaged by CBCT imaging and classified into 4 groups on the basis of external root morphology. Internal morphologic features, including the shapes of the buccal and palatal orifices and distances of bifurcation of the buccal-palatal and mesiobuccal-distobuccal root canals from the cementoenamel junction (CEJ), were measured. The teeth were classified into 4 groups on the basis of external morphology: group A, separation of the buccal and palatal roots with bifurcation of the former into the mesiobuccal and distobuccal roots (n = 22); group B, fusion of 2 buccal roots with the palatal root being separate (n = 19); group C, complete or partial fusion of the distobuccal and palatal roots (n = 9); and group D, fusion of all 3 roots (n = 6). The buccal orifice was mainly triangular/heart shaped. The distance of bifurcation of the buccal-palatal root canals from the CEJ in group A differed significantly from those in groups B and C (P < .05). There were significant differences in the distance of bifurcation of the mesiobuccal-distobuccal root canals from the CEJ among groups A, B, and C (P < .05). Four teeth exhibited C-shaped root canal systems of different configurations. The external and internal morphologies of 3-rooted maxillary first premolars vary considerably. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Tuberculous otitis in infants: temporal bone histopathology and clinical extrapolation.

PubMed

Nicolau, Yamileth; Northrop, Clarinda; Eavey, Roland

2006-08-01

The study of infant temporal bones with tuberculosis (TB) of the middle ear and mastoid could provide information to assist with clinical diagnosis in this population. The TB pandemic has become a critical global public health problem. With the rising incidence of the disease, otolaryngologists might encounter an increased frequency of otologic TB. Pediatric temporal bone reports of TB are rare. Light microscopic examination was performed on both temporal bones from an infant who died as a result of miliary TB. The tympanic membranes were thickened with dilated blood vessels, yet were intact without perforations. Purulence, granulation tissue, and classic tubercles were observed in the middle ears and mastoids. Serous labyrinthitis and inflammatory cells surrounding the Cranial Nerve VIII in the internal auditory canal were observed in the inner ear. The histological findings suggest that a clinical presentation of infantile tuberculous otitis media and mastoiditis could be a patient with otoscopic findings consistent with common otitis media with an intact tympanic membrane, likely in conjunction with inner ear symptoms. Lacking the classic finding of multiple tympanic membrane perforations, tuberculous otitis might be underappreciated in this population.

Physiological and behavioral effects of tilt-induced body fluid shifts

NASA Technical Reports Server (NTRS)

Parker, D. E.; Tjernstrom, O.; Ivarsson, A.; Gulledge, W. L.; Poston, R. L.

1983-01-01

This paper addresses the 'fluid shift theory' of space motion sickness. The primary purpose of the research was the development of procedures to assess individual differences in response to rostral body fluid shifts on earth. Experiment I examined inner ear fluid pressure changes during head-down tilt in intact human beings. Tilt produced reliable changes. Differences among subjects and between ears within the same subject were observed. Experiment II examined auditory threshold changes during tilt. Tilt elicited increased auditory thresholds, suggesting that sensory depression may result from increased inner ear fluid pressure. Additional observations on rotation magnitude estimation during head-down tilt, which indicate that rostral fluid shifts may depress semicircular canal activity, are briefly described. The results of this research suggest that the inner ear pressure and auditory threshold shift procedures could be used to assess individual differences among astronauts prior to space flight. Results from the terrestrial observations could be related to reported incidence/severity of motion sickness in space and used to evaluate the fluid shift theory of space motion sickness.

A validated methodology for the 3D reconstruction of cochlea geometries using human microCT images

NASA Astrophysics Data System (ADS)

Sakellarios, A. I.; Tachos, N. S.; Rigas, G.; Bibas, T.; Ni, G.; Böhnke, F.; Fotiadis, D. I.

2017-05-01

Accurate reconstruction of the inner ear is a prerequisite for the modelling and understanding of the inner ear mechanics. In this study, we present a semi-automated methodology for accurate reconstruction of the major inner ear structures (scalae, basilar membrane, stapes and semicircular canals). For this purpose, high resolution microCT images of a human specimen were used. The segmentation methodology is based on an iterative level set algorithm which provides the borders of the structures of interest. An enhanced coupled level set method which allows the simultaneous multiple image labeling without any overlapping regions has been developed for this purpose. The marching cube algorithm was applied in order to extract the surface from the segmented volume. The reconstructed geometries are then post-processed to improve the basilar membrane geometry to realistically represent physiologic dimensions. The final reconstructed model is compared to the available data from the literature. The results show that our generated inner ear structures are in good agreement with the published ones, while our approach is the most realistic in terms of the basilar membrane thickness and width reconstruction.

High-frequency hearing impairment assessed with cochlear microphonics.

PubMed

Zhang, Ming

2012-09-01

Cochlear microphonic (CM) measurements may potentially become a supplementary approach to otoacoustic emission (OAE) measurements for assessing low-frequency cochlear functions in the clinic. The objective of this study was to investigate the measurement of CMs in subjects with high-frequency hearing loss. Currently, CMs can be measured using electrocochleography (ECochG or ECoG) techniques. Both CMs and OAEs are cochlear responses, while auditory brainstem responses (ABRs) are not. However, there are inherent limitations associated with OAE measurements such as acoustic noise, which can conceal low-frequency OAEs measured in the clinic. However, CM measurements may not have these limitations. CMs were measured in human subjects using an ear canal electrode. The CMs were compared between the high-frequency hearing loss group and the normal-hearing control group. Distortion product OAEs (DPOAEs) and audiogram were also measured. The DPOAE and audiogram measurements indicate that the subjects were correctly selected for the two groups. Low-frequency CM waveforms (CMWs) can be measured using ear canal electrodes in high-frequency hearing loss subjects. The difference in amplitudes of CMWs between the high-frequency hearing loss group and the normal-hearing group is insignificant at low frequencies but significant at high frequencies.

Sound pressure distribution within natural and artificial human ear canals: forward stimulation.

PubMed

Ravicz, Michael E; Tao Cheng, Jeffrey; Rosowski, John J

2014-12-01

This work is part of a study of the interaction of sound pressure in the ear canal (EC) with tympanic membrane (TM) surface displacement. Sound pressures were measured with 0.5-2 mm spacing at three locations within the shortened natural EC or an artificial EC in human temporal bones: near the TM surface, within the tympanic ring plane, and in a plane transverse to the long axis of the EC. Sound pressure was also measured at 2-mm intervals along the long EC axis. The sound field is described well by the size and direction of planar sound pressure gradients, the location and orientation of standing-wave nodal lines, and the location of longitudinal standing waves along the EC axis. Standing-wave nodal lines perpendicular to the long EC axis are present on the TM surface >11-16 kHz in the natural or artificial EC. The range of sound pressures was larger in the tympanic ring plane than at the TM surface or in the transverse EC plane. Longitudinal standing-wave patterns were stretched. The tympanic-ring sound field is a useful approximation of the TM sound field, and the artificial EC approximates the natural EC.

Numerical simulation of the role of the utriculo-endolymphatic valve in the rotation-sensing capabilities of semicircular canals.

PubMed

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

2016-06-14

The utriculo-endolymphatic valve (UEV) has an uncertain function, but its opening and closure have been predicted to maintain a constant endolymphatic pressure within the semicircular canals (SCCs) and the utricle of the inner ear. Here, the study׳s aim was to examine the role of the UEV in regulating the capabilities of the 3 SCCs in sensing angular acceleration by using the finite element method. The results of the developed model showed endolymphatic flow and cupula displacement patterns in good agreement with previous experiments. Moreover, the open valve was predicted to permit endolymph exchange between the 2 parts of the membranous labyrinth during head rotation and, in comparison to the closed valve, to result in a reinforced endolymph flow in the utricle and an enhanced or weakened cupula deflection. Further, the model predicted an increase in the size of the orifice would result in greater endolymph exchange and thereby to a greater impact on cupula deflection. The model findings suggest the UEV plays a crucial role in the preservation of inner ear sensory function. Copyright © 2016 Elsevier Ltd. All rights reserved.

Tympanic-response transition in ICE: Dependence upon the interaural cavity's shape

NASA Astrophysics Data System (ADS)

van Hemmen, J. Leo

More than half of the terrestrial vertebrates have internally coupled ears (ICE), where an interaural cavity of some shape acoustically couples the eardrums. Hence what the animal's auditory system perceives is not the outside stimulus but the superposition of outside and internal pressure on the two eardrums, resulting in so-called internal time and level difference, iTD and iLD, which are keys to sound localization. For a cylindrical shape, it is known that on the frequency axis two domains with appreciably increased iTD and iLD values occur, segregated by the eardrum's fundamental frequency. Here we analyze the case where, as in nature, two or more canals couple the eardrums so that, by opening one of the canals, the animal can switch from coupled to two independent ears. We analyze the iTD/iLD transition and its dependence upon the interaural cavity's size and shape. As compared to a single connection, the iTD performance is preserved to a large extent. Nonetheless, the price to pay for freedom of choice is a reduced frequency range with high-iTD plateau. Work done in collaboration with A.P. Vedurmudi; partially supported by BCCN-Munich.

Congenital atresia of the external ear and tinnitus: a new syndrome.

PubMed

Shulman, Abraham; Strashun, Arnold M; Goldstein, Barbara; Lenhardt, Martin L

2006-01-01

Congenital atresia of the external ears and severe tinnitus has been reported by two patients to be contralateral to the atretic ear. The use of the nuclear medicine imaging technique of single-photon emission computed tomography (SPECT) of brain has demonstrated hypoperfusion in brain areas supplied by the middle cerebral artery on the side of the atretic ear. Ultrahigh-frequency audiometry (UHFA) has revealed a bilateral loss of hearing greater than expected for the age of affected patients. Quantitative electroencephalography (QEEG) has shown a significant central nervous system electrical dysfunction correlated with the SPECT of brain findings. One case is reported in detail at this time. Completion of the medical audiological tinnitus patient protocol, including SPECT of brain, UHFA, and QEEG, accurately established the clinical tinnitus diagnosis of predominantly a central-type tinnitus, a clinical hypothesis that the medical significance of the tinnitus is a "soft" sign of cerebrovascular disease, and provided a rationale for treatment directed to a presumed ischemia of brain based on a receptor-targeted therapy targeted to the GABA-A receptor, resulting in significant tinnitus relief. Questions that have arisen include (1) the incidence of occurrence of hypoperfusion of the middle cerebral artery in congenital atresia patients; (2) implications and long-term consequences of this finding in this patient population for development of cerebrovascular disease; (3) brain plasticity for tinnitus relief (i.e., neuronal reprogramming, particularly in response to treatment recommendations for complaints of the cochleovestibular system in general and specifically for tinnitus); (4) the clinical significance of the UHFA thresholds of bilateral hearing loss greater than expected for the age of the patient; and (5) whether congenital atresia of the external ear may be part of a syndrome that includes hypoperfusion in brain areas supplied by the middle cerebral artery on the side of the atretic ear, ultra-high-frequency bilateral loss of hearing greater than expected for the age of the patient, and significant central nervous system electrical dysfunction. As far as we can determine, these findings, highlighted by the brain SPECT, have not previously been reported in patients with congenital atresia of the external ear.

An in vitro comparison of root canal transportation by reciproc file with and without glide path.

PubMed

Nazarimoghadam, Kiumars; Daryaeian, Mohammad; Ramazani, Nahid

2014-09-01

The aim of ideal canal preparation is to prevent iatrogenic aberrations such as transportation. The aim of this study was to evaluate the root canal transportation by Reciproc file with and without glide path. Thirty acrylic-resin blocks with a curvature of 60° and size#10 (2% taper) were assigned into two groups (n= 15). In group 1, the glide path was performed using stainless steel k-files size#10 and 15 at working length In group 2, canals were prepared with Reciproc file system at working length. By using digital imaging software (AutoCAD 2008), the pre-instrumentation and post-instrumentation digital images were superimposed over, taking the landmarks as reference points. Then the radius of the internal and external curve of the specimens was calculated at three α, β and γ points (1mm to apex as α, 3mm to apex as β, and 5mm to apex as γ). The data were statically analyzed using the independent T-test and Mann-Whitney U test by SPSS version 16. Glide path was found significant for only external curve in the apical third of the canal; that is, 5mm to apex (P=0.005). But in the other third, canal modification was not significant (P> 0.008). Canal transportation in the apical third of the canal seems to be significantly reduced when glide path is performed using reciprocating files.

An In Vitro Comparison of Root Canal Transportation by Reciproc File With and Without Glide Path

PubMed Central

Nazarimoghadam, Kiumars; Daryaeian, Mohammad; Ramazani, Nahid

2014-01-01

Objective: The aim of ideal canal preparation is to prevent iatrogenic aberrations such as transportation. The aim of this study was to evaluate the root canal transportation by Reciproc file with and without glide path. Materials and Methods: Thirty acrylic-resin blocks with a curvature of 60° and size#10 (2% taper) were assigned into two groups (n= 15). In group 1, the glide path was performed using stainless steel k-files size#10 and 15 at working length In group 2, canals were prepared with Reciproc file system at working length. By using digital imaging software (AutoCAD 2008), the pre-instrumentation and post-instrumentation digital images were superimposed over, taking the landmarks as reference points. Then the radius of the internal and external curve of the specimens was calculated at three α, β and γ points (1mm to apex as α, 3mm to apex as β, and 5mm to apex as γ). The data were statically analyzed using the independent T-test and Mann-Whitney U test by SPSS version 16. Results: Glide path was found significant for only external curve in the apical third of the canal; that is, 5mm to apex (P=0.005). But in the other third, canal modification was not significant (P> 0.008). Conclusion: Canal transportation in the apical third of the canal seems to be significantly reduced when glide path is performed using reciprocating files. PMID:25628682

Shaping magnetic fields to direct therapy to ears and eyes.

PubMed

Shapiro, B; Kulkarni, S; Nacev, A; Sarwar, A; Preciado, D; Depireux, D A

2014-07-11

Magnetic fields have the potential to noninvasively direct and focus therapy to disease targets. External magnets can apply forces on drug-coated magnetic nanoparticles, or on living cells that contain particles, and can be used to manipulate them in vivo. Significant progress has been made in developing and testing safe and therapeutic magnetic constructs that can be manipulated by magnetic fields. However, we do not yet have the magnet systems that can then direct those constructs to the right places, in vivo, over human patient distances. We do not yet know where to put the external magnets, how to shape them, or when to turn them on and off to direct particles or magnetized cells-in blood, through tissue, and across barriers-to disease locations. In this article, we consider ear and eye disease targets. Ear and eye targets are too deep and complex to be targeted by a single external magnet, but they are shallow enough that a combination of magnets may be able to direct therapy to them. We focus on how magnetic fields should be shaped (in space and time) to direct magnetic constructs to ear and eye targets.

Radiation injury to the temporal bone

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guida, R.A.; Finn, D.G.; Buchalter, I.H.

1990-01-01

Osteoradionecrosis of the temporal bone is an unusual sequela of radiation therapy to the head and neck. Symptoms occur many years after the radiation is administered, and progression of the disease is insidious. Hearing loss (sensorineural, conductive, or mixed), otalgia, otorrhea, and even gross tissue extrusion herald this condition. Later, intracranial complications such as meningitis, temporal lobe or cerebellar abscess, and cranial neuropathies may occur. Reported here are five cases of this rare malady representing varying degrees of the disease process. They include a case of radiation-induced necrosis of the tympanic ring with persistent squamous debris in the external auditorymore » canal and middle ear. Another case demonstrates the progression of radiation otitis media to mastoiditis with bony sequestration. Further progression of the disease process is seen in a third case that evolved into multiple cranial neuropathies from skull base destruction. Treatment includes systemic antibiotics, local wound care, and debridement in cases of localized tissue involvement. More extensive debridement with removal of sequestrations, abscess drainage, reconstruction with vascularized tissue from regional flaps, and mastoid obliteration may be warranted for severe cases. Hyperbaric oxygen therapy has provided limited benefit.« less

[Microtia-atresia: clinical, genetic and genomic aspects].

PubMed

Aguinaga-Ríos, Mónica; Frías, Sara; Arenas-Aranda, Diego J; Morán-Barroso, Verónica Fabiola

Mexico has a prevalence of microtia of 7.37/10,000 (newborns), 3 times higher than the prevalence reported in other populations (USA 2-3/10,000). Microtia is defined as a congenital malformation of the external ear characterized by a small auricular lobe with an abnormal shape. It is more often unilateral and on the right side. Males are more frequently affected than females. It can occur as an isolated defect or can be associated with other abnormalities such as stenosis of the external auditory canal. In three of the main pediatric hospitals in Mexico, microtia is among the most important causes of attendance in the Genetics Department. Microtia-atresia must be considered as a major malformation with important repercussions in hearing function requiring multidisciplinary medical care in order to limit the disability associated and to provide genetic counseling. Its etiology is complex. Only in a minor number of cases it has been possible to identify a main genetic component (as in monogenic presentations) or a main environmental cause (as in fetal alcohol syndrome or pregestational diabetes). In most cases this malformation is multifactorial. Due to the relevance that the frequency of microtia atresia has in different health services in Mexico, it is important that all medical professionals are aware of its clinical, molecular and inherited characteristics. Copyright © 2014 Hospital Infantil de México Federico Gómez. Publicado por Masson Doyma México S.A. All rights reserved.

Is it necessary to occlude the ear in bone-conduction testing at 4 kHz, in order to prevent air-borne radiation affecting the results?

PubMed

Tate Maltby, Maryanne; Gaszczyk, David

2015-01-01

To re-evaluate the current BSA recommendation that the test ear should be occluded during the bone-conduction procedure at frequencies above 2 kHz to prevent audible air-borne radiation. Pure-tone audiometry was undertaken during routine hearing tests. The audiograms of fifty-two ears met the criteria for the study and were included. Bone conduction at 4 kHz was tested in three different conditions: test ear open/occluded by earplug and occluded by circumaural earphone. Forty-four adults aged 41-77 years with average hearing levels from normal to severe loss. All complied fully with the test procedure. No audiogram had a significant conductive element. There was no significant difference in each of the three test situations. Only two audiograms showed any (5 dB) difference at 4 kHz when bone conduction was retested with the ear occluded. The errors that result in a false air-bone gap at 4 kHz would not appear to be due to air-borne radiation. Failure to occlude the ear canal at 4 kHz, where air-borne radiation is greatest, makes no significant difference to the audiometric results. It is therefore suggested that it is unnecessary to block the test ear during routine pure-tone bone-conduction testing to prevent audible air-borne radiation, and that this should no longer form part of normal clinical practice.

Surfer's ear: external auditory exostoses are more prevalent in cold water surfers.

PubMed

Kroon, David F; Lawson, M Louise; Derkay, Craig S; Hoffmann, Karen; McCook, Joe

2002-05-01

The study goal was to demonstrate the prevalence and severity of external auditory exostoses (EAEs) in a population of surfers and to examine the relationship between these lesions and the length of time surfed as well as water temperature in which the swimmers surfed. It was hypothesized that subjects who predominantly surfed in colder waters had more frequent and more severe exostoses. Two hundred two avid surfers (91% male and 9% female, median age 17 years) were included in the study. EAEs were graded based on the extent of external auditory canal patency; grades of normal (100% patency), mild (66% to 99% patency), and moderate-severe (<66% patency) were assigned. Otoscopic findings were correlated with data collected via questionnaires that detailed surfing habits. There was a 38% overall prevalence of EAEs, with 69% of lesions graded as mild and 31% graded as moderate-severe. Professional surfers (odds ratio 3.8) and those subjects who surfed predominantly in colder waters (odds ratio 5.8) were found to be at a significantly increased risk for the development of EAEs. The number of years surfed was also found to be significant, increasing one's risk for developing an exostosis by 12% per year and for developing more severe lesions by 10% per year. Individuals who had moderate-severe EAEs were significantly more likely to be willing to surf in colder waters than were those who had mild EAEs (odds ratio 4.3). EAEs are more prevalent in cold water surfers, and additional years surfing increase one's risk not only for developing an EAE but also for developing more severe lesions.

Minimally invasive functional approach for cholesteatoma surgery.

PubMed

Hanna, Bassem M; Kivekäs, Ilkka; Wu, Yi-Hsuan; Guo, Lee J; Lin, Huang; Guidi, Jessica; Poe, Dennis

2014-10-01

Report the efficacy of a functional minimally invasive approach for cholesteatoma surgery. Retrospective review of surgical cases performed between 1996 and 2008. One hundred sixty-nine patient charts were reviewed in which ears with primary cholesteatomas that extended beyond the mesotympanum were operated on with a plan for canal wall up (CWU) mastoidectomy. The surgical approach consisted of progressive exposure from transcanal to postauricular tympanoplasty to CWU mastoidectomy, as needed, to identify and lyse the fibrous attachments that bind the capsule to the surrounding mucosa. Endoscopic guidance was employed as appropriate to minimize exposure needs. Any planned second-stage operations were attempted with a transcanal approach if appropriate and with endoscopic assistance. One hundred eighty-four ears of 169 patients were included. The median age was 32 years (range, 1-79 years). The mean follow-up was 3.2 years (range, 1-11 years). Eighty-three (45%) were planned for a second-look operation, and three (2%) required unplanned second operations. The overall recurrence rate was 24/184 (13%), and the unexpected residual rate was 5/184 (3%). The residual rate with endoscopy (5/119, 4%,) or without endoscopy (1/65, 2%), were not significantly different. Hearing results in 156 ears improved significantly, from a preoperative pure-tone average (PTA) of 41 dB to a postoperative PTA average of 29 dB (P < .0001). A functional minimally invasive approach to cholesteatoma surgery provided equivalent residual rates but higher recurrence rates compared to published canal wall down mastoidectomy. Endoscopic techniques were helpful in providing adequate views while minimizing exposure. © 2014 The American Laryngological, Rhinological and Otological Society, Inc.

Co-existence of Benign Paroxysmal Positional Vertigo and Meniere's Syndrome.

PubMed

Yetişer, Sertaç

2017-04-01

Recent studies indicate interrelation of benign paroxysmal positional vertigo (BPPV) and Meniere's disease (MD). These two entities may have different clinical characteristics. Five hundred thirty patients with BPPV evaluated between 2009-2015 were enrolled in the study. 351 patients who had no clear problem associated with BPPV (idiopathic) and 17 patients with MD were analyzed in detail. The age, sex, site of involvement, type of BPPV, symptom duration, and treatment outcome were compared. Meniere's disease + BPPV was more common in the female population (2/15; 7.5 v 127/224; 1.8, p<0.05). Comparative analysis of average age was not statistically significant (42.82±9.94 v. 40.29±1.65, p=0.601). There was no difference in right and left ear involvement between groups. Lateral canal involvement was more common in the BPPV + MD group (9/17; 53% v. 100/351; 28%, p<0.05). BPPV was ipsilateral to the ear with MD in 75% of patients and it was present before the diagnosis of BPPV in 82.3% of patients. Comparative analysis of cure rate between idiopathic BPPV and BPPV + MD after one session was significant (64.7% v 78%, p<0.05). Benign paroxysmal positional vertigo associated with MD presented a divergent picture. It was more frequent in females. Lateral canal involvement was higher. Patients had MD before the development of BPPV and they had prolonged symptoms, which raised a question of diagnostic delay since these two problems were in the same ear in majority of patients. Finally, relief of symptoms required more attempts of repositioning maneuvers.

Development of a method for estimating oesophageal temperature by multi-locational temperature measurement inside the external auditory canal

NASA Astrophysics Data System (ADS)

Nakada, Hirofumi; Horie, Seichi; Kawanami, Shoko; Inoue, Jinro; Iijima, Yoshinori; Sato, Kiyoharu; Abe, Takeshi

2017-09-01

We aimed to develop a practical method to estimate oesophageal temperature by measuring multi-locational auditory canal temperatures. This method can be applied to prevent heatstroke by simultaneously and continuously monitoring the core temperatures of people working under hot environments. We asked 11 healthy male volunteers to exercise, generating 80 W for 45 min in a climatic chamber set at 24, 32 and 40 °C, at 50% relative humidity. We also exposed the participants to radiation at 32 °C. We continuously measured temperatures at the oesophagus, rectum and three different locations along the external auditory canal. We developed equations for estimating oesophageal temperatures from auditory canal temperatures and compared their fitness and errors. The rectal temperature increased or decreased faster than oesophageal temperature at the start or end of exercise in all conditions. Estimated temperature showed good similarity with oesophageal temperature, and the square of the correlation coefficient of the best fitting model reached 0.904. We observed intermediate values between rectal and oesophageal temperatures during the rest phase. Even under the condition with radiation, estimated oesophageal temperature demonstrated concordant movement with oesophageal temperature at around 0.1 °C overestimation. Our method measured temperatures at three different locations along the external auditory canal. We confirmed that the approach can credibly estimate the oesophageal temperature from 24 to 40 °C for people performing exercise in the same place in a windless environment.

Comparison of two vertical condensation obturation techniques: Touch 'n Heat modified and System B.

PubMed

Silver, G K; Love, R M; Purton, D G

1999-08-01

The aims of this study were firstly to compare the area of canal occupied by gutta-percha, sealer or voids using the System B heating device with that obtained by a modified vertical condensation technique using the Touch 'n Heat: and secondly to compare the temperature changes at the root canal wall and external root surface during obturation with the above techniques. Forty-five resin blocks, each with a standardized, simulated, prepared main root canal and five lateral canals, were assigned to three equal experimental groups. The canals were obturated using either the System B technique at two different temperature settings, or vertical condensation with a Touch 'n Heat instrument as the heat source. A heat transfer model was used to simultaneously record internal and external root surface temperature elevations during obturation by the three techniques. Data were analysed using unpaired Student's t-test and Mann-Whitney U-test. Both obturation techniques produced root fillings consisting of over 90% gutta-percha at most levels, although the percentages of sealer and voids 2-3 mm from the working length following System B obturation were higher than those found following modified vertical condensation. Modified vertical condensation resulted in more gutta-percha in lateral canals. Obturation was accomplished more quickly using the System B, and temperature elevations produced during obturation with the System B were significantly less (P < 0.001) than with vertical condensation. An elevation of external root surface temperature by more than 10 degrees C occurred during vertical condensation. The results suggest that the System B may produce an acceptable obturation and that the use of a Touch 'n Heat source during vertical condensation may result in damage to the periodontium.

Effects of consecutive wideband tympanometry trials on energy absorbance measures of the middle ear.

PubMed

Burdiek, Laina M; Sun, Xiao-Ming

2014-10-01

Wideband acoustic immittance (WAI) is a new technique for assessing middle ear transfer function. It includes energy absorbance (EA) measures and can be acquired with the ear canal pressure varied, known as wideband tympanometry (WBTymp). The authors of this study aimed to investigate effects of consecutive WBTymp testing on EA. Data were collected in 29 young adults with normal hearing and middle ear status. Before and after 8 successive WBTymp runs, EA was also measured at ambient pressure. Subsequently, two 226-Hz tympanometry tests were performed. EA systematically changed over the WBTymp trials in a frequency-specific manner: increase for low frequencies (below 1.5 kHz) and decrease for high frequencies (around 2 kHz and 5 to 6 kHz). The changes, although small, were significant. Much larger EA changes were measured at ambient pressure. The test-retest difference of 226-Hz tympanogram measures was much smaller than previously reported. Consecutive tympanometry testing alters EA measures of the middle ear. This phenomenon could be mainly attributed to change in stiffness at the eardrum, called tympanometric preconditioning. This also has effects on baseline WBTymp outcomes. This effect should be taken into account as a procedural variable in both research and clinical applications of WAI measurements.

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

PubMed Central

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

Endodontic management of radix paramolaris with six canals: a clinical case report.

PubMed

Acharya, N; Singh, A; Samant, P S; Gautam, V

2013-01-01

Endodontic therapy of mandibular molars is a challenging task due to its varied root canal morphology. A mandibular first molar with additional buccal root (Radix paramolaris) and additional distolingual root (Radix Entomolaris) is an example of its varied anatomy. A successful management of atypical root canal configurations is an important aspect in determining the success rate of root canal therapy. The detail knowledge of the root morphology and canal anatomy allows the clinician for accurate location of the extra roots and canals and accordingly the refinement of the access cavity for the stress free entry of complex anatomy. Hence, for a successful root canal therapy, clinician must be aware of the external and internal anatomic variations .The aim of this clinical case report is to present and describe the unusual presence of two separate mesial roots and six root canals in mandibular first molar, detected during routine endodontic therapy.

[A case of Bezold's abscess associated with cholesteatoma].

PubMed

Furukawa, K; Arai, E; Kobayashi, T; Takasaka, T

1992-12-01

Since the advent of antibiotics, otogenic complications have decreased considerably. However, incomplete antibiotic therapy has altered the clinical course of middle ear disease so as to be more insidious. This paper reports a case of Bezold's abscess associated with cholesteatoma. A 48-year-old man visited our hospital presenting with a 4-day history of right otorrhea and a tender swelling in the right neck. Physical examination showed a febrile patient (38.8 degrees C) with right facial paresis and trismus. A hyperemic, hard and tender swelling was observed in his right neck from the lateral cervical to the mental region. The tympanic membrane was invisible because of granulation and swelling of the posterior wall of the external auditory canal. Intravenous clindamycin and ceftazidime therapy was started immediately. A CT-scan revealed a diffuse shadow with bony destruction in the right mastoid cortex. Extensive abscess formation was also found in the right sternocleidomastoid muscle, in the anterior neck and in the posterior neck. He was diagnosed as having Bezold's abscess associated with cholesteatoma. Radical mastoidectomy and drainage of the neck abscess was performed on the third day under general anesthesia. The mastoid cavity was found to be filled with pus and cholesteatoma debris. A small area of defective bone was found at the mastoid tip, through which there were communications between the mastoid cavity and the abscesses in the neck. Bony destruction was also found in the horizontal and vertical portion of the facial canal. Bacteroides and three kinds of gram-negative rods were cultured from the mastoid cavity.(ABSTRACT TRUNCATED AT 250 WORDS)

The internal cranial anatomy of Romundina stellina Ørvig, 1975 (Vertebrata, Placodermi, Acanthothoraci) and the origin of jawed vertebrates—Anatomical atlas of a primitive gnathostome

PubMed Central

2017-01-01

Placoderms are considered as the first jawed vertebrates and constitute a paraphyletic group in the stem-gnathostome grade. The acanthothoracid placoderms are among the phylogenetically most basal and morphologically primitive gnathostomes, but their neurocranial anatomy is poorly understood. Here we present a near-complete three-dimensional skull of Romundina stellina, a small Early Devonian acanthothoracid from the Canadian Arctic Archipelago, scanned with propagation phase contrast microtomography at a 7.46 μm isotropic voxel size at the European Synchrotron Radiation Facility, Grenoble, France. This is the first model of an early gnathostome skull produced using this technique, and as such represents a major advance in objectivity compared to past descriptions of placoderm neurocrania on the basis of grinding series. Despite some loss of material along an oblique crack, most of the internal structures are remarkably preserved, and most of the missing structures can be reconstructed by symmetry. This virtual approach offers the possibility to connect with certainty all the external foramina to the blood and nerve canals and the central structures, and thus identify accurate homologies without destroying the specimen. The high level of detail enables description of the main arterial, venous and nerve canals of the skull, and other perichondrally ossified endocranial structures such as the palatoquadrate articulations, the endocranial cavity and the inner ear cavities. The braincase morphology appears less extreme than that of Brindabellaspis, and is in some respects more reminiscent of a basal arthrodire such as Kujdanowiaspis. PMID:28170434

CRITICAL ANALYSIS OF ARTIFICIAL TEETH FOR ENDODONTIC TEACHING

PubMed Central

Nassri, Maria Renata Giazzi; Carlik, Jaime; da Silva, Camila Roberta Nepomuceno; Okagawa, Renata Elisa; Lin, Suzy

2008-01-01

The purpose of this study was to evaluate the use of artificial teeth for endodontic teaching. A questionnaire was prepared and submitted to 18 professors of Endodontics from different Brazilian universities to evaluate the following features of five cloudy resin artificial teeth: internal and external anatomy; coronal chambers regarding their size, shape and canal path; root canal regarding their size, shape and position; fulfillment of the pulp chamber and root canals by considering the texture, quantity, color, and ease of handling; resin hardness and visualization of the radiographic image. The results presented favorable opinions, in terms of internal and external anatomy, coronal pulp chambers and root canal and handling and radiographic imaging. The contents of the pulp space and hardness of the teeth were considered satisfactory. The average grade assigned to the artificial tooth quality was 8.4, in a 0-10 scale. In conclusion, the artificial teeth have potential to replace the natural teeth in endodontic teaching; however, improvements are still necessary to reach a better quality model. PMID:19089288

Critical analysis of artificial teeth for endodontic teaching.

PubMed

Nassri, Maria Renata Giazzi; Carlik, Jaime; da Silva, Camila Roberta Nepomuceno; Okagawa, Renata Elisa; Lin, Suzy

2008-01-01

The purpose of this study was to evaluate the use of artificial teeth for endodontic teaching. A questionnaire was prepared and submitted to 18 professors of Endodontics from different Brazilian universities to evaluate the following features of five cloudy resin artificial teeth: internal and external anatomy; coronal chambers regarding their size, shape and canal path; root canal regarding their size, shape and position; fulfillment of the pulp chamber and root canals by considering the texture, quantity, color, and ease of handling; resin hardness and visualization of the radiographic image. The results presented favorable opinions, in terms of internal and external anatomy, coronal pulp chambers and root canal and handling and radiographic imaging. The contents of the pulp space and hardness of the teeth were considered satisfactory. The average grade assigned to the artificial tooth quality was 8.4, in a 0-10 scale. In conclusion, the artificial teeth have potential to replace the natural teeth in endodontic teaching; however, improvements are still necessary to reach a better quality model.

Journal of Special Operations Medicine. Volume 2, Edition 1, Winter 2002

DTIC Science & Technology

2002-01-01

regarding clean surgi- cal procedures that an antibiotic treatment regime must be based upon the expected pathogens, appro- priate pharmacokinetic properties...conduction apparatus toDiagram of ear Auricle Epitympanic recess Malleus (head) Incus Crura of stapes Tegmen tympani Cochlear nerve Vesibular nerve Facial...Prominence of lateral semicircular canal Scala vestibuli Cochlear duct containing spiral organ (of Corti) Scala tympaniAuditory (Eustachian) tube Round

Complete occipitalization of the atlas with bilateral external auditory canal atresia.

PubMed

Dolenšek, Janez; Cvetko, Erika; Snoj, Žiga; Meznaric, Marija

2017-09-01

Fusion of the atlas with the occipital bone is a rare congenital dysplasia known as occipitalization of the atlas, occipitocervical synostosis, assimilation of the atlas, or atlanto-occipital fusion. It is a component of the paraxial mesodermal maldevelopment and commonly associated with other dysplasias of the craniovertebral junction. External auditory canal atresia or external aural atresia is a rare congenital absence of the external auditory canal. It occurs as the consequence of the maldevelopment of the first pharyngeal cleft due to defects of cranial neural crest cells migration and/or differentiation. It is commonly associated with the dysplasias of the structures derived from the first and second pharyngeal arches including microtia. We present the coexistence of the occipitalization of the atlas and congenital aural atresia, an uncommon combination of the paraxial mesodermal maldevelopment, and defects of cranial neural crest cells. The association is most probably syndromic as minimal diagnostic criteria for the oculoariculovertebral spectrum are fulfilled. From the clinical point of view, it is important to be aware that patients with microtia must obtain also appropriate diagnostic imaging studies of the craniovetebral junction due to eventual concomitant occipitalization of the atlas and frequently associated C1-C2 instability.

Relation of motion sickness susceptibility to vestibular and behavioral measures of orientation

NASA Technical Reports Server (NTRS)

Peterka, Robert J.

1994-01-01

The objective of this proposal is to determine the relationship of motion sickness susceptibility to vestibulo-ocular reflexes (VOR), motion perception, and behavioral utilization of sensory orientation cues for the control of postural equilibrium. The work is focused on reflexes and motion perception associated with pitch and roll movements that stimulate the vertical semicircular canals and otolith organs of the inner ear. This work is relevant to the space motion sickness problem since 0 g related sensory conflicts between vertical canal and otolith motion cues are a likely cause of space motion sickness. Results of experimentation are summarized and modifications to a two-axis rotation device are described. Abstracts of a number of papers generated during the reporting period are appended.

Peripheral and central auditory specialization in a gliding marsupial, the feathertail glider, Acrobates pygmaeus.

PubMed

Aitkin, L M; Nelson, J E

1989-01-01

Two specialized features are described in the auditory system of Acrobates pygmaeus, a small gliding marsupial. Firstly, the ear canal includes a transverse disk of bone that partly occludes the canal near the eardrum. The resultant narrow-necked chamber above the eardrum appears to attenuate sound across a broad frequency range, except at 27-29 kHz at which a net gain of sound pressure occurs. Secondly, the lateral medulla is hypertrophied at the level of the cochlear nucleus, forming a massive lateral lobe comprised of multipolar cells and granule cells. This lobe has connections with the auditory nerve and the cerebellum. Speculations are advanced about the functions of these structures in gliding behaviour and predator avoidance.

Morphological evaluation of maxillary second molars with fused roots: a micro-CT study.

PubMed

Ordinola-Zapata, R; Martins, J N R; Bramante, C M; Villas-Boas, M H; Duarte, M H; Versiani, M A

2017-12-01

To evaluate the internal and external morphologies of fused-rooted maxillary second molars by means of micro-computed tomography (micro-CT) analysis. A total of 100 fused-rooted maxillary second molars from a Brazilian subpopulation were divided into six groups according to the root morphology. The samples were scanned at a resolution of 19.6 μm and evaluated with regard to the external morphology of the roots, the root canal configuration, the percentage frequency of C-shaped canals and isthmuses, as well as the morphology of the root canal system at 1, 2 and 3 mm from the anatomical apex of the fused roots. The most prevalent root canal fusions were type 1, mesiobuccal root fused with distobuccal root (32%), followed by type 3, DB root fused with P root (27%), and type 4, MB root fused with DB root, and P root fused with MB or DB roots (21%). The prevalence of C-shaped root canal systems were 22%. Depending on the type of root fusion, the percentage frequency of isthmuses in the apical level varied from 9.3% to 42.8%, whilst the presence of apical deltas ranged from 18.5% to 57.1% of teeth. The root canal system of maxillary second molars with fused roots may have a high incidence of merging canals, isthmuses, apical deltas and C-shaped configurations. © 2017 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Human tooth and root canal morphology reconstruction using magnetic resonance imaging.

PubMed

Drăgan, Oana Carmen; Fărcăşanu, Alexandru Ştefan; Câmpian, Radu Septimiu; Turcu, Romulus Valeriu Flaviu

2016-01-01

Visualization of the internal and external root canal morphology is very important for a successful endodontic treatment; however, it seems to be difficult considering the small size of the tooth and the complexity of the root canal system. Film-based or digital conventional radiographic techniques as well as cone beam computed tomography provide limited information on the dental pulp anatomy or have harmful effects. A new non-invasive diagnosis tool is magnetic resonance imaging, due to its ability of imaging both hard and soft tissues. The aim of this study was to demonstrate magnetic resonance imaging to be a useful tool for imaging the anatomic conditions of the external and internal root canal morphology for endodontic purposes. The endodontic system of one freshly extracted wisdom tooth, chosen for its well-known anatomical variations, was mechanically shaped using a hybrid technique. After its preparation, the tooth was immersed into a recipient with saline solution and magnetic resonance imaged immediately. A Bruker Biospec magnetic resonance imaging scanner operated at 7.04 Tesla and based on Avance III radio frequency technology was used. InVesalius software was employed for the 3D reconstruction of the tooth scanned volume. The current ex-vivo experiment shows the accurate 3D volume rendered reconstruction of the internal and external morphology of a human extracted and endodontically treated tooth using a dataset of images acquired by magnetic resonance imaging. The external lingual and vestibular views of the tooth as well as the occlusal view of the pulp chamber, the access cavity, the distal canal opening on the pulp chamber floor, the coronal third of the root canals, the degree of root separation and the apical fusion of the two mesial roots, details of the apical region, root canal curvatures, furcal region and interradicular root grooves could be clearly bordered. Magnetic resonance imaging offers 3D image datasets with more information than the conventional radiographic techniques. Due to its ability of imaging both hard and soft dental tissues, magnetic resonance imaging can be successfully used as a 3D diagnostic imaging technique in dentistry. When choosing the imaging method, dental clinicians should weight the benefit-risk ratio, taking into account the costs associated to magnetic resonance imaging and the harmful effects of ionizing radiations when cone beam computed tomography or conventional x-ray are used.

Association of external auditory canal atresia, vertical talus, and hypertelorism: confirmation of Rasmussen syndrome.

PubMed

Julia, Sophie; Pedespan, Jean Michel; Boudard, Philippe; Barbier, Richard; Gavilan-Cellie, Isabelle; Chateil, Jean François; Lacombe, Didier

2002-06-15

In 1979, Rasmussen et al. reported six members of a family with congenital, bilateral, symmetrical, and isolated subtotal atresia of the external auditory canal, bilateral foot abnormalities, and increased interocular distance. The family history suggested autosomal dominant inheritance of the syndrome. We report a 3-year-old girl whose symptoms are compatible with this diagnosis. Therefore, we suggest confirmation of the description by Rasmussen et al. as a distinct entity and suggest the term Rasmussen syndrome for this condition. Copyright 2002 Wiley-Liss, Inc.

PVDF-Based Piezoelectric Microphone for Sound Detection Inside the Cochlea: Toward Totally Implantable Cochlear Implants.

PubMed

Park, Steve; Guan, Xiying; Kim, Youngwan; Creighton, Francis Pete X; Wei, Eric; Kymissis, Ioannis John; Nakajima, Hideko Heidi; Olson, Elizabeth S

2018-01-01

We report the fabrication and characterization of a prototype polyvinylidene fluoride polymer-based implantable microphone for detecting sound inside gerbil and human cochleae. With the current configuration and amplification, the signal-to-noise ratios were sufficiently high for normally occurring sound pressures and frequencies (ear canal pressures >50-60 dB SPL and 0.1-10 kHz), though 10 to 20 dB poorer than for some hearing aid microphones. These results demonstrate the feasibility of the prototype devices as implantable microphones for the development of totally implantable cochlear implants. For patients, this will improve sound reception by utilizing the outer ear and will improve the use of cochlear implants.

PVDF-Based Piezoelectric Microphone for Sound Detection Inside the Cochlea: Toward Totally Implantable Cochlear Implants

PubMed Central

Guan, Xiying; Kim, Youngwan; Creighton, Francis (Pete) X.; Wei, Eric; Kymissis, Ioannis(John); Nakajima, Hideko Heidi; Olson, Elizabeth S.

2018-01-01

We report the fabrication and characterization of a prototype polyvinylidene fluoride polymer-based implantable microphone for detecting sound inside gerbil and human cochleae. With the current configuration and amplification, the signal-to-noise ratios were sufficiently high for normally occurring sound pressures and frequencies (ear canal pressures >50–60 dB SPL and 0.1–10 kHz), though 10 to 20 dB poorer than for some hearing aid microphones. These results demonstrate the feasibility of the prototype devices as implantable microphones for the development of totally implantable cochlear implants. For patients, this will improve sound reception by utilizing the outer ear and will improve the use of cochlear implants. PMID:29732950

Surgical management of polyotia.

PubMed

Pan, Bo; Qie, Shuyan; Zhao, Yanyong; Tang, Xiaojun; Lin, Lin; Yang, Qinghua; Zhuang, Hongxing; Jiang, Haiyue

2010-08-01

Polyotia is an extremely rare type of congenital external ear malformation, which is defined as an accessory ear that is large enough to resemble an additional pinna. The terms 'mirror ear' or 'accessory ear' are sometime used. We present our methods in correcting this malformation and summarise the aetiology. The posterior part of the polyotia may presents with a normal ear, a constricted ear or a microtic ear. Free auricular composite tissue transplantation was used to correct the constricted ear. Ear reconstruction was applied in cases of microtia. The anterior auricle was mainly used to form the tragus. 7 cases polyotia were treated between 2004 and 2008. After free auricular composite tissue transplantation the size of the constricted ear and the contralateral ear was similar. In microtia cases the reconstructed ears were natural looking and had a satisfactory three-dimensional contour. The extra tissue of the anterior ear was excised and the tragus was reconstructed. Through operative intervention tailored to the individual case natural-looking and symmetric ears were acquired. The aetiology of polyotia probably relates to abnormal migration of neural crest cell. Copyright 2009 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Auditory changes in acromegaly.

PubMed

Tabur, S; Korkmaz, H; Baysal, E; Hatipoglu, E; Aytac, I; Akarsu, E

2017-06-01

The aim of this study is to determine the changes involving auditory system in cases with acromegaly. Otological examinations of 41 cases with acromegaly (uncontrolled n = 22, controlled n = 19) were compared with those of age and gender-matched 24 healthy subjects. Whereas the cases with acromegaly underwent examination with pure tone audiometry (PTA), speech audiometry for speech discrimination (SD), tympanometry, stapedius reflex evaluation and otoacoustic emission tests, the control group did only have otological examination and PTA. Additionally, previously performed paranasal sinus-computed tomography of all cases with acromegaly and control subjects were obtained to measure the length of internal acoustic canal (IAC). PTA values were higher (p < 0.001 for right ears and p = 0.001 for left ears), and SD scores were (p = 0.002 for right ears and p = 0.002 for left ears) lower in acromegalic patients. IAC width in acromegaly group was narrower compared to that in control group (p = 0.03 for right ears and p = 0.02 for left ears). When only cases with acromegaly were taken into consideration, PTA values in left ears had positive correlation with growth hormone and insulin-like growth factor-1 levels (r = 0.4, p = 0.02 and r = 0.3, p = 0.03). Of all cases with acromegaly 13 (32%) had hearing loss in at least one ear, 7 (54%) had sensorineural type and 6 (46%) had conductive type hearing loss. Acromegaly may cause certain changes in the auditory system in cases with acromegaly. The changes in the auditory system may be multifactorial causing both conductive and sensorioneural defects.

Dynamic Properties of Human Tympanic Membrane Based on Frequency-Temperature Superposition

PubMed Central

Zhang, Xiangming; Gan, Rong Z.

2012-01-01

The human tympanic membrane (TM) transfers sound in the ear canal into the mechanical vibration of the ossicles in the middle ear. The dynamic properties of TM directly affect the middle ear transfer function. The static or quasi-static mechanical properties of TM were reported in the literature, but the dynamic properties of TM over the auditory frequency range are very limited. In this paper, a new method was developed to measure the dynamic properties of human TM using the Dynamic-Mechanical Analyzer (DMA). The test was conducted at the frequency range of 1 to 40 Hz at three different temperatures: 5°, 25° and 37°C. The frequency-temperature superposition was applied to extend the testing frequency range to a much higher level (at least 3800 Hz). The generalized linear solid model was employed to describe the constitutive relation of the TM. The storage modulus E’ and the loss modulus E” were obtained from 11 specimens. The mean storage modulus was 15.1 MPa at 1 Hz and 27.6 MPa at 3800 Hz. The mean loss modulus was 0.28 MPa at 1 Hz and 4.1 MPa at 3800 Hz. The results show that the frequency-temperature superposition is a feasible approach to study the dynamic properties of the ear soft tissues. The dynamic properties of human TM obtained in this study provide a better description of the damping behavior of ear tissues. The properties can be transferred into the finite element (FE) model of the human ear to replace the Rayleigh type damping. The data reported here contribute to the biomechanics of the middle ear and improve the accuracy of the FE model for the human ear. PMID:22820983

Inner ear manifestations in CHARGE: Abnormalities, treatments, animal models, and progress toward treatments in auditory and vestibular structures.

PubMed

Choo, Daniel I; Tawfik, Kareem O; Martin, Donna M; Raphael, Yehoash

2017-12-01

The inner ear contains the sensory organs for hearing and balance. Both hearing and balance are commonly affected in individuals with CHARGE syndrome (CS), an autosomal dominant condition caused by heterozygous pathogenic variants in the CHD7 gene. Semicircular canal dysplasia or aplasia is the single most prevalent feature in individuals with CHARGE leading to deficient gross motor skills and ambulation. Identification of CHD7 as the major gene affected in CHARGE has enabled acceleration of research in this field. Great progress has been made in understanding the role of CHD7 in the development and function of the inner ear, as well as in related organs such as the middle ear and auditory and vestibular neural pathways. The goals of current research on CHD7 and CS are to (a) improve our understanding of the pathology caused by CHD7 pathogenic variants and (b) to provide better tools for prognosis and treatment. Current studies utilize cells and whole animals, from flies to mammals. The mouse is an excellent model for exploring mechanisms of Chd7 function in the ear, given the evolutionary conservation of ear structure, function, Chd7 expression, and similarity of mutant phenotypes between mice and humans. Newly recognized developmental functions for mouse Chd7 are shedding light on how abnormalities in CHD7 might lead to CS symptoms in humans. Here we review known human inner ear phenotypes associated with CHD7 pathogenic variants and CS, summarize progress toward diagnosis and treatment of inner ear-related pathologies, and explore new avenues for treatment based on basic science discoveries. © 2017 Wiley Periodicals, Inc.

Chronic anal fissure: morphometric analysis of the anal canal at 3.0 Tesla MR imaging.

PubMed

Erden, Ayşe; Peker, Elif; Gençtürk, Zeynep Bıyıklı

2017-02-01

OBJECTıVE: To compare the morphometric data relating to the muscular structures of the anal canal, in patients with chronic anal fissure and in control group, examined at a 3.0 Tesla MR system. Forty-seven consecutive patients with chronic anal fissure and randomly selected 40 patients who had no claims for perianal disease during their life time were included in the study. T2-weighted sagittal, high-resolution (HR) T2-weighted, and contrast-enhanced fat-suppressed T1-weighted oblique axial and oblique coronal images were retrospectively analyzed by two observers in consensus. Thickness of sphincteric muscles, anal canal length, anorectal angle, thickness of anococcygeal ligament, depth of Minor triangle, width between subcutaneous sphincters, vascularity of posterior commissure, visibility of posterosuperior projection of external sphincter, and angle between the distal anal canal and posterosuperior projection of external sphincter (H angle) in patients and in controls were compared and analyzed using t test, Mann-Whitney U test, and Spearman correlation. The patients with chronic anal fissure had longer anal canal (51.50 mm ± 0.91 vs. 44.11 mm ± 0.71; p = 0.000), thicker internal anal sphincter muscle at mid-anal level (4.18 ± 0.15 vs. 3.39 ± 0.07; p = 0.007), and wider space between subcutaneous external sphincters (11.39 ± 0.50 vs. 6.89 ± 0.22; p = 0.000). In patients, there was a positive correlation between H angle and external sphincter thickness at proximal (r = 0.347; p = 0.021), middle (r = 0427; p = 0.000), and distal (r = 0.518; p = 0.000)) levels of the anal canal. CONCLUSıON: 3.0 Tesla MR imaging provides detailed information about the morphometric changes in the anal sphincter muscles in patients with chronic anal fissure.

Clinical spectrum of patients with erosion of the inner ear by jugular bulb abnormalities.

PubMed

Friedmann, David R; Le, B Thuy; Pramanik, Bidyut K; Lalwani, Anil K

2010-02-01

Anatomic variants of the jugular bulb (JB) are common; however, abnormalities such as large high riding JB and JB diverticulum (JBD) are uncommon. Rarely, the abnormal JB may erode into the inner ear. The goal of our study is to report a large series of patients with symptomatic JB erosion into the inner ear. Retrospective review in an academic medical center. Eleven patients with JB abnormality eroding into the inner ear were identified on computed tomography (CT) scan of the temporal bone. Age at presentation was from 5 years to 82 years with six males and five females. The large JB or JBD eroded into the vestibular aqueduct (n = 9) or the posterior semicircular canal (n = 4). The official radiology report usually identified the JB abnormality; however, erosion into these structures by the JB was not mentioned in all but one case. All patients were symptomatic with five having conductive hearing loss (CHL) and three complaining of pulsatile tinnitus. Those with pulsatile tinnitus and four of five with CHL had erosion into the vestibular aqueduct. Vestibular evoked myogenic potential (VEMP) findings in three of six patients were consistent with dehiscence of the inner ear. High riding large JB or JBD can erode into the inner ear and may be associated with CHL and/or pulsatile tinnitus. CT scan is diagnostic and should be examined specifically for these lesions. As patients with pulsatile tinnitus may initially undergo a magnetic resonance imaging scan, identification of JB abnormality should prompt CT scan or VEMP testing to evaluate for inner ear erosion.