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Ossiculoplasty: A Prospective Study of 80 Cases

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Shrinivas Shripatrao Chavan

2014-07-01

Full Text Available Introduction: The use of ossicular graft material in ossicular chain reconstruction has significantly improved hearing results hearing after tympanoplasty and tympanomastoid surgery for chronic otitis media. Today, otologists have a wide array of tools from which to choose, but may find it difficult to know which middle ear implant works best.   Materials and Methods: A prospective study of 80 patients who underwent ossiculoplasty was performed in the ear, nose, and throat (ENT department at a tertiary health care facility from 2011 to 2013. Patients with chronic suppurative otitis media with an air-bone gap (ABG of >25 dB with ossicular involvement were included in the study. Total ossicular replacement prosthesis (TORP, partial ossicular replacement prosthesis (PORP, and refashioned incus were used. Success was defined as ABG   Results: The majority patients were of middle age with moderate conductive hearing loss. Incus was the most susceptible ossicle. Overall success rate in this study was 80.0% with an average change of 15.76 dB in ABG.   Conclusion:  With continuing advances in our understanding of middle ear mechanics, the results of ossiculoplasty are improving and results can be very rewarding in experienced hands. Severity of preoperative ear discharge, preoperative mastoid cellularity, presence of disease, and surgical procedure proved to be significant prognostic factors. Autograft incus and PORP fared better when the malleus handle was present while TORP gave better results when the malleus handle was eroded.  

Cholesteatoma behind an intact tympanic membrane: histopathologic evidence for a tympanic membrane origin.

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Sudhoff, H; Linthicum, F H

2001-07-01

Several theories have been proposed with respect to the origin and pathogenesis of cholesteatoma behind an intact tympanic membrane. The authors describe a case of cholesteatoma behind an intact tympanic membrane in a 71-year-old man with a history of tympanic membrane retraction fixed to the incus without evidence of a perforation. The membrane eventually became detached, and remnants of keratinizing squamous epithelium were found on the incus. Mechanisms such as metaplasia, ectopic epidermis rests, or ingrowth of meatal epidermis have been proposed to explain the pathogenesis of cholesteatoma behind an intact tympanic membrane. These findings, based on temporal bone histopathology, support the role of an acquired epidermal rest. This case report provides evidence that cholesteatoma behind an intact tympanic membrane can be established from a resolved retraction of the pars tensa of the tympanic membrane.

Discontinuity of the incudo-stapedial joint within a fully aerated middle ear and mastoid on computed tomography: A clinico-radiological study of its aetiology and clinical consequence

International Nuclear Information System (INIS)

Connor, S.E.J.; Pai, I.; Jiang, D.; Spiers, A.J.D.; Fitzgerald-O'Connor, A.

2012-01-01

Aim: To investigate the aetiology and clinical consequences of incudo-stapedial (IS) discontinuity when it is demonstrated on computed tomography (CT) within a fully aerated middle ear and mastoid. Methods and materials: Patients with CT evidence of IS discontinuity within a fully aerated middle ear and mastoid were prospectively identified. Clinical history, otoscopic findings, audiometry, and CT data were evaluated. Predefined criteria were used to determine the likely aetiology of IS discontinuity, whether it was diagnosed prior to the CT study, and the clinical consequences in terms of degree of conductive hearing loss and requirement for surgical correction. The range of CT appearances was evaluated. Results: The IS discontinuity in 34/36 ears was felt to be due to incus erosion secondary to chronic otitis, on the basis of clinical history and otoscopic findings. The IS discontinuity was rarely evident prior to CT with long-process deficiency being identified in only 5/36 cases. The mean air bone gap was only 22.5 dB. The ossicular defect was surgically addressed in only four cases. The incus deficiency was confined to the lower-third on CT in 19/36 cases. Conclusion: When IS discontinuity is demonstrated within a fully aerated middle ear and mastoid, the most likely aetiology is of acquired incus erosion due to chronic otitis media. The IS discontinuity on CT is usually not evident otoscopically. It usually results in only mild conductive hearing loss and the ossicular discontinuity was rarely surgically addressed in the present series.

Experimental measurement and modeling analysis on mechanical properties of incudostapedial joint.

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Zhang, Xiangming; Gan, Rong Z

2011-10-01

The incudostapedial (IS) joint between the incus and stapes is a synovial joint consisting of joint capsule, cartilage, and synovial fluid. The mechanical properties of the IS joint directly affect the middle ear transfer function for sound transmission. However, due to the complexity and small size of the joint, the mechanical properties of the IS joint have not been reported in the literature. In this paper, we report our current study on mechanical properties of human IS joint using both experimental measurement and finite element (FE) modeling analysis. Eight IS joint samples with the incus and stapes attached were harvested from human cadaver temporal bones. Tension, compression, stress relaxation and failure tests were performed on those samples in a micro-material testing system. An analytical approach with the hyperelastic Ogden model and a 3D FE model of the IS joint including the cartilage, joint capsule, and synovial fluid were employed to derive mechanical parameters of the IS joint. The comparison of measurements and modeling results reveals the relationship between the mechanical properties and structure of the IS joint.

Clinical application of 3D spiral CT of the auditory ossicular chain and labyrinth: Preliminary report

International Nuclear Information System (INIS)

Huang Yong; Wang Yisheng

1998-01-01

Purpose: To assess the clinical application and limitation of 3D spiral CT of the auditory ossicular chain and labyrinth. Methods: 3D reconstruction of the auditory ossicular chain and labyrinth, including multiplanar reformation (MPR), minimum or maximum intensity projection (MinIP or MaxIP) and shaded surface display (SSD), were performed with 1 mm slice thickness, 5 cm field of view and 0.1 mm reconstruction interval spiral CT in 14 normal subjects, 15 patients with middle ear diseases. Results: With use of 3D reconstruction images in 14 normal subjects, 13 cases of ossicular chain showed that the long process of the incus was parallel to the manubrium and projected inferomedian toward the cochlear promontory, the incus-stapedial joint was like a 'L-shape' structure, and in 8 cases of labyrinth reconstruction, the cochlea and the three semicircular canals were demonstrated. 9 cholesteatomas of 13 chronic otitis media demonstrated destruction of ossicular chain of varying degrees. In 2 cases with congenital abnormality, ossicle dysplasia was seen. Conclusion: 3D CT is a useful technique for evaluating anatomic malformations and diseases of middle and inner ear, but there are still few pitfalls

A Study of Ossiculoplasty in Chronic Otitis Media using different types of Prostheses

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Parthapratim Laha

2013-12-01

Full Text Available Abstract Introduction: A wide range of prostheses, autologus and synthetic are available for use these days. Ideally, the ossicular reconstruction prosthesis should be biocompatible, safe, easy to handle and capable of efficient sound transmission. Aim and objectives: To study operative ease and post-operative hearing results in patients undergoing ossiculoplasty with different types of prostheses. Materials and methods: A prospective randomized study of 25 patients with Chronic Otitis Media, undergoing ossiculoplasty was conducted at Command Hospital, Kolkata. Tragal cartilage was used in 05 patients, conchal cartilage in 05, refashioned incus in 05, hydroxyapatite in 05 and titanium prostheses in 05 patients. Subjects with mixed hearing loss, multiple co-morbidities and revision surgeries were excluded. Hearing assessment was done by pure tone audiometry pre-operatively and 04 and 12 weeks postoperatively. Results were analyzed statistically. Results: Using tragal or conchal cartilage took almost equal time as autologus incus. Using synthetic material saved time. Titanium prosthesis gives maximum surgical ease. Post-operative air-bone gap reduction within 20 dB was seen in all, irrespective of type of prostheses.  Conclusion: Surgical ease is considerably better with titanium prostheses; however hearing results are equally good in all.

A qualitative diagnosis of stapes lesions by helical 3-dimensional CT

International Nuclear Information System (INIS)

Kawaue, Akifumi; Yamanaka, Noboru; Kuki, Kiyonori; Nishimura, Michihiko

2001-01-01

To evaluate the usefulness of 3D-CT combined with super-selective stapes's image processing (3D-SS) for the qualitative diagnosis of stapes lesions, a new parameter, the crus index, was designed and applied to CT image diagnosis of conductive hearing loss. The crus index was designed as a new parameter indicating the average of changing rate of cross section area of crus image when the lower thresholed of CT window width reduced by 100 H.U.. The crus index was calculated with 3D-SS in 5 ears with otosclerosis, in 5 ears with eroded long process of incus or crus of stapes, an ear with facial neurinoma (susp), an ear with soft density tissue on only stapes and 6 control ears and the diagnostic usefulness was evaluated as comparing the intra-/post-operative diagnosis. The crus index was significantly higher in ears with eroded long process of incus or crus of stapes (3.58+1.36) than otosclerosis (1.33+0.35) or controls (1.44+0.3). These data suggest that the crus index using 3D-SS may be a useful parameter in diagnosing conductive hearing loss. (author)

Reassessment of the La Ferrassie 3 Neandertal ossicular chain.

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Quam, Rolf; Martínez, Ignacio; Arsuaga, Juan Luis

2013-04-01

The ossicular chain in La Ferrassie 3 was briefly described in the monograph on the La Ferrassie Neandertal children, but to date has not been the subject of detailed study. We provide new data on these important fossils and re-examine some previous suggestions of derived Neandertal features in the middle ear ossicles based on more limited evidence. The malleus shows a curved lateral margin of the manubrium and a relatively large head. The incus shows a tall articular facet, a depressed area on the medial surface of the body, a straight anterior border of the long process and a more closed angle between the processes. The stapes shows an asymmetrical configuration of the crura, with an anteriorly skewed head, and generally small dimensions, including a smaller and relatively wider stapedial footplate. These same features can also be seen in the few other Neandertal ear ossicles known, suggesting that a consistent anatomical pattern characterizes the Neandertal ossicular chain. While the phylogenetic polarity of many of these features remains to be clarified, the asymmetrical stapes and anteriorly skewed stapedial head appear to be derived Neandertal features. In addition, while the larger malleus head and incus articular facet in La Ferrassie 3 might reflect larger body mass in Neandertals, the larger stapes footplates in Homo sapiens cannot be explained by changes in body mass. Indeed, H. sapiens seems to depart from the general mammalian pattern in combining an increase in stapes footplate size with a decrease in body mass. Although the malleus/incus lever ratio in La Ferrassie 3 is similar to that in H. sapiens, Neandertals appear to be characterized by a slightly different spatial relationship and articulation of the ossicular chain within the tympanic cavity. While only limited inferences can be drawn regarding hearing ability based on the ossicles, the few physiologically relevant dimensions in the La Ferrassie 3 ear bones are similar to H

Journal of Special Operations Medicine. Volume 9, Edition 3, Summer 2009

Science.gov (United States)

2009-01-01

aids in stability of forefoot adduction and aids in stability of inversion (Figure 68 and 69). Figure 65: Proximal and distal anchoring strips...reach the middle ear where they strike the eardrum and cause it to vibrate. The vibrations set the middle-ear bones (malleus, incus, stapes) in...exposure to an intense sound. It occurs when excessive sound energy strikes the inner ear. Exposure to noise from firearm use during military service

Ossicular erosions in the dry ear: CT diagnosis

International Nuclear Information System (INIS)

Swartz, J.D.; Nunnelly, D.E.; Zwillenberg, S.; Berger, A.S.; Popky, G.L.

1986-01-01

Erosions of the ossicular chain can occur as a complication of noncholesteatomatous chronic otitis media. These defects may appear on CT of the healed ''dry'' ear. Ischemic necrosis is the most likely etiology; however, acid phosphatase-containing lysosomes are also implicated. The incus (particularly the long and lenticular processes) is by far the most vulnerable ossicle. Coronal CT is especially valuable in diagnosing these erosions. Fibrous replacement of the incudostapedial articulation may be diagnosed on CT when an unusually wide ''joint'' is seen on axial CT scans

Systematic Review of Ossicular Chain Anatomy: Strategic Planning for Development of Novel Middle Ear Prostheses.

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Kamrava, Brandon; Roehm, Pamela C

2017-08-01

Objective To systematically review the anatomy of the ossicular chain. Data Sources Google Scholar, PubMed, and otologic textbooks. Review Methods A systematic literature search was performed on January 26, 2015. Search terms used to discover articles consisted of combinations of 2 keywords. One keyword from both groups was used: [ ossicular, ossicle, malleus, incus, stapes] and [ morphology, morphometric, anatomy, variation, physiology], yielding more than 50,000 hits. Articles were then screened by title and abstract if they did not contain information relevant to human ossicular chain anatomy. In addition to this search, references of selected articles were studied as well as suggested relevant articles from publication databases. Standard otologic textbooks were screened using the search criteria. Results Thirty-three sources were selected for use in this review. From these studies, data on the composition, physiology, morphology, and morphometrics were acquired. In addition, any correlations or lack of correlations between features of the ossicular chain and other features of the ossicular chain or patient were noted, with bilateral symmetry between ossicles being the only important correlation reported. Conclusion There was significant variation in all dimensions of each ossicle between individuals, given that degree of variation, custom fitting, or custom manufacturing of prostheses for each patient could optimize prosthesis fit. From published data, an accurate 3-dimensional model of the malleus, incus, and stapes can be created, which can then be further modified for each patient's individual anatomy.

[Computerized study of perioperative difficulties of stapedectomy].

Science.gov (United States)

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.

A study with high resolution computed tomography of bone destruction in cholesteatoma

International Nuclear Information System (INIS)

Kikuchi, Shigeru; Yamaso, Tatsuya; Higo, Ryusaburo; Senba, Tetsuo; Iinuma, Yoshitaka.

1992-01-01

The modes and incidences of bone destruction in the middle ear cholesteatoma were evaluated by high resolution computed tomography, comparing with chronic otitis media with central perforation (COM) as control. The head of the malleus, the body and long process of the incus were more markedly destroyed in cholesteatoma than in COM with statistical significance. With the further extension of cholesteatoma into the antrum, the tegmen of the aditus ad antrum, the lateral semicircular canal, the handle of the malleus and the Korner's septum were involved in bone destruction. (author)

Mass distribution and rotational inertia of "microtype" and "freely mobile" middle ear ossicles in rodents.

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Lavender, Danielle; Taraskin, Sergei N; Mason, Matthew J

2011-12-01

The middle ears of seven species of rodents, including four hamster species, were examined under light microscopy and through micro-CT imaging. Hamsters were found to possess a spectrum of ossicular morphologies ranging from something approaching "freely mobile" (Mesocricetus) to something nearer the "microtype" (Cricetulus), although no hamster has an orbicular apophysis of the malleus. Rats, mice and Calomyscus were found to have typically microtype ossicles. To explore the functional effects of these morphological differences, CT scan data were used to calculate the magnitudes of the moments of inertia and positions of the centres of mass and principal rotational axes for the malleus-incus complexes. Microtype species were found to have much greater ossicular inertias, relative to size, about the "anatomical axis" extending between anterior process of the malleus and short process of the incus; ossicular centres of mass were displaced further from this axis. Calculated inertial values were then put into an existing model of middle ear function (Hemilä et al., 1995), in order to see whether the more accurate data would improve predictions of upper hearing limits. For the rat and mouse they did, but this was not so for the hamster Mesocricetus. This might indicate that the inner rather than the middle ear limits hearing in this species, or might simply reflect other shortcomings of the model. Functional differences appear to exist even among rodent ears of the same general type, but the adaptive significance of these differences remains enigmatic. Copyright © 2011 Elsevier B.V. All rights reserved.

Middle Ear Exploration Results in Suspected Otosclerosis Cases Referred to Amir-Almomenin and Golsar Hospitals, Rasht, 2001-2011: Are Ossicular and Footplate Area Anomalies Rare?

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Shadman Nemati

2013-06-01

Full Text Available Introduction: Otosclerosis is a disease of bony labyrinth. Structural changes in the labyrinth often cause ossicular fixation, and thus conductive hearing loss. The purpose of this study was to evaluate middle ear exploration findings and frequency of ossicular and footplate area anomalies in patients with suspected otosclerosis referred to Amiralmomenin and Golsar Hospitals in Rasht, Iran.   Materials and Methods: In 47 patients undergone middle ear exploration in Amiralmomenin and Golsar hospitals from April 2001 to March 2011, the intraoperative findings, and other data were extracted from the medical records of the patients. The data was analyzed using SPSS 17 software.   Results: Frequency of fixation of stapes, malleus, and incus by age and sex in patients undergoing middle ear exploration showed that stapes had been fixed in 39 patients, malleus in 6 patients, and incus in 21 patients. Analysis of data showed that there was no significant association between sex and age with fixation of any of ossicles (P>0/05. Middle ear anomalies were seen in 16 cases (34.0%. Overhanging of facial nerve in 4 cases, thick stapedial crura in 5 cases, and perilymph gusher in 2 cases were the most frequent anomalies.   Conclusion:  This study show that the results of middle ear explorations in our patients in the north of Iran is somehow different from the typical otosclerotic cases, although the frequency of ossicular anomalies is better to be evaluated and compared in different areas of Iran, and other countries. 

Vibroplasty in mixed and conductive hearing loss: comparison of different coupling methods.

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Vyskocil, Erich; Riss, Dominik; Honeder, Clemens; Arnoldner, Christoph; Hamzavi, Jafar-Sasan; Baumgartner, Wolf-Dieter; Flak, Stefan; Gstoettner, Wolfgang

2014-06-01

To evaluate modified coupling techniques of the Vibrant Soundbridge system in patients with mixed and conductive hearing loss and to compare it with conventional vibroplasty. Retrospective study. Two different groups were evaluated: 1) nine cases of conventional incus vibroplasty in comparison with 2) nine patients with modified coupling of the floating mass transducer. In the modified coupling approach, the vibrant floating mass transducer was attached to 1) the stapes/oval window, 2) the round window, or 3) the drilled promontory bone (promontory fenestration window). In three patients, an additional ossiculoplasty was performed. Preoperative and postoperative aided and unaided pure-tone and free-field audiometry and Freiburg monosyllabic word test were used to assess hearing outcome. Functional hearing gain obtained in patients with mixed and conductive hearing loss who underwent modified coupling was 39 dB. Patients with pure sensorineural hearing loss who received conventional incus coupling showed a functional hearing gain of 25 dB. Average functional gain was 41 dB in the oval window group, 45 dB in the round window group, and 30 dB in the promontory fenestration window group. Word recognition test revealed an average improvement of 51% and 21% in the modified and in the conventional approach, respectively. Modified vibroplasty is a safe and effective treatment for patients with conductive and mixed hearing loss. Coupling the floating mass transducer to the promontory bone (promontory fenestration window) is a viable option in chronically disabled ears if oval and round window coupling is not possible. 4. © 2013 The American Laryngological, Rhinological and Otological Society, Inc.

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

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Matthew J Mason

Full Text Available 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.

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

Science.gov (United States)

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.

Middle ear bones of a mid-gestation ruminant foetus extracted from x-ray computed tomography

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

2016-10-01

The timing of ossification of middle ear ossicles has been extensively studied in humans. This is an exception since it is vastly unknown in the +5000 extant species of placentals. As a preliminary approach, a cow foetus (around 115 days of gestation) was visualized using X-ray microtomography (μCT) and the ossicles including stapes, incus, and malleus could be extracted from the data set. All three bones have already undergone substantial ossification, which allow comparison to adult middle ear bones. Their ossification at this stage parallels ossification in humans at a comparable stage of gestation. While full ossification is not yet achieved almost all the morphological characters of the ossicles are observed. Bone tissue is still very porous, the stapes does not have the characteristic plate-like footplate, the lenticular process of the incus is missing and the manubrium of the malleus is very thin and not yet complete. Despite all this, the ossicles are articulate with each other and perfectly with the bony labyrinth. The stapes footplate is positioned on the oval window but is smaller than the latter while it should perfectly fit to transmit sound vibrations to the cochlea. All ossicles, especially the stapes, have not yet reached adult size, while the bony labyrinth already has. This is the first detailed description of a set of middle ear bones in a placental at mid-gestation based on high-resolution μCT. Similarities in ossification timing with humans encourage more work to be done on foetuses to understand if a general rule for placental mammals exists.

3D-CT of the temporal bone area with high-speed processing

International Nuclear Information System (INIS)

Hattori, Taku

1994-01-01

Three-dimentional (3D)-CT was introduced to represent abnormal findings in the temporal bone area utilizing a SOMATOM DRH CT scanner with accessory 3D reconstruction software and an exclusive high-speed 3D processing system, VOXEL FLINGER. In a patient with eosinophilic granuloma, a defect in the squamous part of the temporal bone was demonstrated suggesting exposure of the dura mater during surgery. In a patient with a normal ear, well-developed mastoid cavity, a part of the handle and the head of the malleus, the incudomalleal joint, the short limb, body and a part of the long limb of the incus and the round window niche were demonstrated. In a case of chronic otitis media, poorly developed mastoid cavity and a possible defect of the tip of the long limb of the incus were demonstrated, in contrast to the patient with the normal ear. 3D-CT yields objective and solid images which are useful for diagnosis, treatment planning and explanation of the pathology to patients and their family. To obtain convincing 3D images, physicians themselves have to choose exact rotation angles. It is not adequate to reconstruct original CT data using a CT computer with accessory 3D software whose processing capability is not good enough for this purpose. The conclusion is as follows: 1) it is necessary and effective to transfer original CT data into the memory of the exclusive high-speed 3D processing system and 2) process the data by the voxel memory method to establish a clinically valuable 3D-CT imaging system. (author)

Tympanoplasty with ionomeric cement

DEFF Research Database (Denmark)

Kjeldsen, A D; Grøntved, A M

2000-01-01

with isolated erosion of the long incus process have been treated with a new surgical technique in which the ossicular chain was rebuilt with ionomeric cement. The results in hearing performance (mean pure-tone average (PTA) 0.5, 1 and 2 kHz) were evaluated pre- and post-surgery, and compared to those...... of > 10 dB, in 4 there was a slight improvement and in 2 a decline. The difference was not statistically significant. Hearing improvement using ionomeric cement in type II tympanoplasty was satisfactory. Reconstruction of the ossicular chain with ionomeric cement is recommended, as the procedure is easy...

Anatomy, Physiology and Function of the Auditory System

Science.gov (United States)

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.

Development of re-locatable head frame system using hydraulic arms for fractionated stereotactic radiotherapy and CT evaluation of repositioning accuracy

International Nuclear Information System (INIS)

Kitamura, Masayuki; Kunieda, Etsuo; Kawaguchi, Osamu; Ando, Yutaka; Shigematsu, Naoyuki; Shiba, Toshiyuki; Kubo, Atsushi

2002-01-01

The purpose of this study was to develop a novel re-locatable head frame system consisting of a dental cast and hydraulic arms as an immobilization device for fractionated stereotactic radiotherapy and to evaluate the repositioning accuracy by measurement of landmark coordinates in repeated computed tomography (CT) examinations. The acrylic dental casts were customized for each patient. First the dental cast was attached to the upper jaw of the patient, then the dental cast was connected to a Leksell stereotactic frame, which was finally secured by two hydraulic arms. Since this system is compatible with the Leksell frame, stereotactic indicators could be used to obtain coordinates of anatomical landmarks of the head. Seven patients treated by fractionated stereotactic radiotherapy underwent repeated quality-assurance CTs during their treatment courses. We evaluated the coordinates of the short process of incus and the top of crista galli as reference points for evaluation of variation in a total of 26 repeat CT data sets, and then x, y, and z fluctuations relative to their positions in the treatment-planning CTs. The distances among the reference points of both processes of incus and the top of crista galli were calculated to evaluate the feasibility of the method. The distances were less than 0.5 mm on averages and less than 1 mm in the standard deviations. The respective fluctuations in the x, y and z directions were less than 1 mm in mean values and less than 2 mm in standard deviations. The fluctuations in distance were less than 2 mm on average and in standard deviations. The fluctuation of the center of three reference points was 0.7 mm on average and the rotation of the cranium was 1.0 degree in average. We concluded that our evaluation method is feasible and the reproducibility of the fixation system is acceptable for its routine use in stereotactic radiotherapy. (author)

Advances tomographic in evaluation of middle ear

International Nuclear Information System (INIS)

Anjos, Mayara Alves Pinheiro dos; Ledo, Mirelle D'arc Frota; Ribeiro, Marcio Duarte

2011-01-01

Computed tomography has a key role in the study of hearing, since through it can be evaluated structures not seen by otoscope. In many clinical situations the diagnosis through this test proves limited, being fundamental examination of the associated image reconstructions: multiplanar reconstruction, maximum intensity projection, and volume-rendering technique. The ossicular chain is a complex formed by the ossicles malleus, incus and stapes, situated in the middle ear; it is difficult to view them in orthogonals planes. This review article intends to demonstrate the importance of post-processing the image of the ossicular chain for a better representation of the anatomy and possible diseases. Reformatting of images helps, significantly, to a better visualization of these structures as related congenital malformations, vascular abnormalities, inflammatory conditions, neoplasia and traumas. (author)

Novel syndrome with conductive hearing loss and congenital glaucoma in three generations.

Science.gov (United States)

Takeuchi, Kazuhiko; Kitano, Masako; Sakaida, Hiroshi; Masuda, Sawako

2017-08-01

The objective of this paper was to describe the clinical and otological findings in multiple members of a family with congenital glaucoma, cardiac anomaly, and conductive hearing loss due to ossicular chain anomalies. We performed a retrospective review of the medical charts and otological materials of multiple members of the same family. Congenital glaucoma and hearing loss were inherited by the proband and her daughter, son, and mother, suggesting autosomal dominant inheritance. The son and daughter also showed atrial septal defects. Exploratory tympanotomies revealed anomalies of the long process of the incus in the proband and her daughter, and tympanoplasty improved hearing loss in both patients. This represents the first description of coexisting congenital glaucoma and conductive hearing loss due to ossicular chain anomalies in multiple members of a single family. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Dependence of RF power on the content and configuration of hydrogen in amorphous hydrogenated silicon by reactive sputtering

Energy Technology Data Exchange (ETDEWEB)

Imura, T; Ushita, K; Mogi, K; Hiraki, A [Osaka Univ., Suita (Japan). Faculty of Engineering

1981-06-01

Infrared absorption spectra at stretching bands of Si-H were investigated in hydrogenated amorphous silicon fabricated by reactive sputtering in the atmosphere of Ar and H/sub 2/ (10 mole%) at various input rf powers in the range from 0.8 to 3.8 W/cm/sup 2/. Hydrogen content mainly due to the configuration of Si=H/sub 2/ in the film increased with the decreasing rf power, as the deposition rate was decreased. On the other hand, the quantity of the monohydride (Si-H) configuration depended less on the power. Attachment of hydrogen molecules onto the fresh and reactive surface of silicon deposited successively was proposed for possible process of hydrogen incusion into amorphous silicon resulting in Si=H/sub 2/ configuration. The photoconductivity increased as the input power became higher, when the deposition rate also increased linearly with the power.

Three dimensional CT imaging of ossicular chain: a preliminary study

International Nuclear Information System (INIS)

Hu Chunhong; Zhong Shenbin; Fu Yindi; Zhu Wei; Wang Xueyuan; Chen Jianhua; Ding Yi

2001-01-01

Objective: To analysis the features of normal and abnormal ossicular chain in three dimensional images and asses the best parameters and its usefulness in diagnosis and treatment of chronic otitis media (COM). Methods: All patients, including 43 patients with normal ears and 24 ears with COM, were examined using spiral CT with inner ear software, 1-mm slice width and 1 pitch. SSD method was used in three dimensional reconstruction and the threshold was 100-300 Hu. Results: In normal cases, Malleus, incus, stapes crura, incudomalleal joints and incudostapedial joints were displayed well, but stapes footplate unsatisfactorily. The disruption of the ossicular chain showed in three-dimensional images in cases of chronic otitis media was in accord with that seen in the operation. Conclusion: It is very important for imaging with high quality through selecting proper parameters, and three-dimensional image can provide valuable information for surgery

CT and MR imaging after middle ear surgery

International Nuclear Information System (INIS)

Koesling, Sabrina; Bootz, F.

2001-01-01

This article describes the current value of imaging in patients after stapes surgery and surgery after chronic otitis media including cholesteatoma. Possibilities and limits of computed tomography (CT) and MRI are described and most important investigation parameters are mentioned. After otosclerosis surgery, CT is the method of first choice in detection of reasons for vertigo and/or recurrent hearing loss in the later postoperative phase. CT may show the position and condition of prosthesis, scarring around the prosthesis and otospongiotic foci. Sometimes, it gives indirect hints for perilymphatic fistulas and incus necrosis. MRI is able to document inner ear complications. CT has a high negative predictive value in cases with a free cavity after mastoidectomy. Localized opacities or total occlusion are difficult to distinguish by CT alone. MRI provides important additional information in the differentiation of cholesterol granuloma, cholesteatoma, effusion, granulation and scar tissue

Evaluation of CT-scanning of the temporal bone in the diagnosis of ear diseases

International Nuclear Information System (INIS)

Murata, Kiyotaka; Isono, Michio; Nishimae, Tadahide; Tamaki, Katsuhiko; Hosoi, Hiroshi; Ohta, Fumihiko

1983-01-01

CT-scanning of 96 temporal bones was carried out to reveal the extension of cholesteatoma, periossicular drainage, fracture lines, enlarged internal acoustic meatus and anomalies of labyrinthine capsules and ossicles. The clinical aspects of CT-scanning of the temporal bone (CTTB) were as follows: 1) Inner ear anomalies were observed in 17 temporal bones of unilateral deafness, high tone loss from unknown origin and fluctuant hearing loss. CTTB may explain the pathology of deafness from unknown origin. 2) Inner ear anomalies may be classified into more detailed groups than before. 3) The extension of cholesteatoma, localization and size of labyrinthine fistula can be estimated prior to surgery. 4) Cholesteatoma in a mastoidectomy cavity may be detected. 5) The malleus and incus may be visualized, although the stapes can hardly be found. 6) Fracture lines of a temporal bone, destruction of the internal acoustic meatus may be clearly detected. (author)

Modeling microstructure of incudostapedial joint and the effect on cochlear input

Science.gov (United States)

Gan, Rong Z.; Wang, Xuelin

2015-12-01

The incudostapedial joint (ISJ) connects the incus to stapes in human ear and plays an important role for sound transmission from the tympanic membrane (TM) to cochlea. ISJ is a synovial joint composed of articular cartilage on the lenticular process and stapes head with the synovial fluid between them. However, there is no study on how the synovial ISJ affects the middle ear and cochlear functions. Recently, we have developed a 3-dimensinal finite element (FE) model of synovial ISJ and connected the model to our comprehensive FE model of the human ear. The motions of TM, stapes footplate, and basilar membrane and the pressures in scala vestibule and scala tympani were derived over frequencies and compared with experimental measurements. Results show that the synovial ISJ affects sound transmission into cochlea and the frequency-dependent viscoelastic behavior of ISJ provides protection for cochlea from high intensity sound.

High resolution computed tomography of auditory ossicles

International Nuclear Information System (INIS)

Isono, M.; Murata, K.; Ohta, F.; Yoshida, A.; Ishida, O.; Kinki Univ., Osaka

1990-01-01

Auditory ossicular sections were scanned at section thicknesses (mm)/section interspaces (mm) of 1.5/1.5 (61 patients), 1.0/1.0 (13 patients) or 1.5/1.0 (33 patients). At any type of section thickness/interspace, the malleal and incudal structures were observed with almost equal frequency. The region of the incudostapedial joint and each component part of the stapes were shown more frequently at a section interspace of 1.0 mm than at 1.5 mm. The visualization frequency of each auditory ossicular component on two or more serial sections was investigated. At a section thickness/section interspace of 1.5/1.5, the visualization rates were low except for large components such as the head of the malleus and the body of the incus, but at a slice interspace of 1.0 mm, they were high for most components of the auditory ossicles. (orig.)

CT and MR imaging after middle ear surgery

Energy Technology Data Exchange (ETDEWEB)

Koesling, Sabrina E-mail: sabrina.koesling@medizin.uni-halle.de; Bootz, F

2001-11-01

This article describes the current value of imaging in patients after stapes surgery and surgery after chronic otitis media including cholesteatoma. Possibilities and limits of computed tomography (CT) and MRI are described and most important investigation parameters are mentioned. After otosclerosis surgery, CT is the method of first choice in detection of reasons for vertigo and/or recurrent hearing loss in the later postoperative phase. CT may show the position and condition of prosthesis, scarring around the prosthesis and otospongiotic foci. Sometimes, it gives indirect hints for perilymphatic fistulas and incus necrosis. MRI is able to document inner ear complications. CT has a high negative predictive value in cases with a free cavity after mastoidectomy. Localized opacities or total occlusion are difficult to distinguish by CT alone. MRI provides important additional information in the differentiation of cholesterol granuloma, cholesteatoma, effusion, granulation and scar tissue.

Functional results of Vibrant Soundbridge middle ear implants in conductive and mixed hearing losses.

Science.gov (United States)

Bernardeschi, Daniele; Hoffman, Caroline; Benchaa, Tarek; Labassi, Samia; Beliaeff, Michel; Sterkers, Olivier; Grayeli, Alexis Bozorg

2011-01-01

Our purpose was to evaluate the results of Vibrant Soundbridge (VSB) in conductive or mixed hearing loss. Twenty-five adult patients (29 ears) with a mixed or conductive hearing loss and various etiologies were included in this retrospective study. The preoperative ipsilateral pure tone average was 71 ± 3.0 dB, and the average bone conduction threshold was 42 ± 2.8 dB (n = 29). The transducer was placed on the long apophysis of the incus (n = 16), in the round window (n = 10) or on the stapes (n = 3). No complications were noted. The bone conduction threshold remained unchanged. VSB was activated in all cases. The postoperative pure tone average without VSB was 63 ± 3.9 dB (n = 24) and with VSB in free-field condition 24 ± 2.1 dB (n = 22). VSB is safe and efficacious for auditory rehabilitation in conductive and mixed hearing losses. Copyright © 2011 S. Karger AG, Basel.

Stereotactic radiosurgery with an upper partial denture

International Nuclear Information System (INIS)

Tayama, Shusaku; Kunieda, Etsuo; Takeda, Atsushi; Takeda, Toshiaki; Oku, Yohei

2009-01-01

A 54-year-old male with partial denture underwent stereotactic radiosurgery with an infrared camera-guided system for a metastatic brain tumor arising from lung cancer. Although this method utilizes a biteplate mounted on the upper jaw to detect head movement, the patient only had four teeth in his upper jaw. In order to stabilize the biteplate, the maxillary denture was fixed to the biteplate with an autopolymerizing resin. In addition, the rest-occlusal position of the lower jaw was impressed on the inferior surface of the biteplate with an autopolymerizing resin. To assess reproducibility and stability, the distance between the left and right incus and left and right markers was measured during pre-planning, as well as before and after stereotactic irradiation. Wearing the biteplate ensures the accuracy of radiotherapy planning for the implementation of radiosurgery in patients who have many maxillary teeth missing. However, a large degree of error was observed when the biteplate was removed. (author)

A comparison of high resolution CT scan of temporal bone and operative findings in middle ear cholesteatoma

Energy Technology Data Exchange (ETDEWEB)

Kweon, Tae Beom; Seong, Hun; Cheon, Mal Soon; Kim, Hack Jin; Jang, Keung Jae; Chun, Byung Hee [Dae Dong General Hospital, Busan (Korea, Republic of)

1993-09-15

To evaluate the value of HRCT imaging in middle ear cholesteatoma, we prospectively analysed the CT images in 28 surgically proven cases with cholesteatomas regarding main site of lesion, ossicular change, facial nerve exposure and fistula formation. The most common main site of lesion was the epitympanum (92.8%). The results of sensitivity, positive predictability, and accuracy by CT imagings were as follows: for ossicular involvement, 94.1%, 88.8%, and 86.2% in malleus, 96.0%, 88.8%, and 85.7% in incus, 81.2%, 81.2%, and 78.5% in stapes; for facial nerve exposure, 66.6%, 57.1%, and 81.2%: for fistula formation, 100%, 75.0%, and 96.4%, respectively. In conclusion, the temoral bone HRCT imaging is an accurate preoperative method in detecting main lesion site, ossicular involvement, fistula formation. Because of the low sensitivity and positive predictability in detecting facial nerve exposure, it is necessary to correlate the HRCT images with the clinical status.

Segmentation and reconstruction of the 3D geometry of the middle and inner ear

Directory of Open Access Journals (Sweden)

Lu Yanfei

2017-01-01

Full Text Available The anatomical model of the ear is of great importance in the design of ossicular prosthesis, cochlear implant electrodes, as well as for the preoperative planning and navigation of surgery. By means of micro-computed tomography (micro-CT and technology of 3D reconstruction, an anatomical model of the middle and inner ear was built. Region of interest includes the ossicular chain (malleus, incus, and stapes, cochlea (scala vestibule-ST, scala tympani-ST, basilar membrane-BM, spiral ligament-SL and osseous spiral lamina-OSL, tympanic membrane-TM, oval window membrane-OWM, round window membrane-OWM and stapedial annular ligament-SAL. The micro-CT images of a cadaver’s temporal bone were acquired by “SkyScan 1076” (Kontich, Belgium, www.skyscan.be and then reconstructed to cross-section images by SkyScan NRecon™ (v1.6.10.4. The image processing and 3D geometry reconstruction of temporal bone were performed by software Mimics® (v14.0, Materialise NV, Leuven, Belgium. The obtained structures are measured and validated against literature data and the results are in good agreement.

A p.(Glu809Lys) Mutation in the WFS1 Gene Associated with Wolfram-like Syndrome: A Case Report.

Science.gov (United States)

Prochazkova, Dagmar; Hruba, Zuzana; Konecna, Petra; Skotakova, Jarmila; Fajkusova, Lenka

2016-12-01

Wolfram-like syndrome (WFSL) is a rare autosomal dominant disease characterised by congenital progressive hearing loss, diabetes mellitus, and optic atrophy. The patient was a boy with the juvenile form of diabetes mellitus and findings which clinically matched the symptoms of Wolfram syndrome. At the age of 3 1/4 years, diabetes mellitus was diagnosed in this boy who also had severe psychomotor retardation, failure to thrive, a dysmorphic face with Peters anomaly type 3 (i.e. posterior central defect with stromal opacity of the cornea, adhering stripes of the iris, and cataract with corneolenticular adhesion), congenital glaucoma, megalocornea, severe hearing impairment, a one-sided deformity of the auricle with atresia of the bony and soft external auditory canal, non-differentiable eardrum, missing os incus, hypothyreosis, and nephrocalcinosis. Molecular-genetic examinations revealed a de novo mutation p.(Glu809Lys) in the WFS1 gene. No mutations were detected in the biological parents. The mutation p.(Glu809Lys) in the WFS1 gene is associated with WFSL.

Differential diagnosis between chronic otitis media with and without cholesteatoma by temporal bone CT: focus on bone change and mass effect

International Nuclear Information System (INIS)

Jung, Cheol Kyu; Park, Dong Woo; Seong, Jin Yong; Lee, Kak Soo; Park Choong Ki; Lee, Seung Ro; Hahm, Chang Kok

2000-01-01

In order to determine specific differences, we compared the temporal bone CT findings of chronic otitis media (COM) with and without cholesteatoma, focusing on bone change. Between 1997 and 1998, 82 patients (84 cases) underwent temporal bone CT and were shown to have COM, with or without cholesteatoma after mastoidectomy and tympanoplasty. There were 36 cases of COM with cholesteatoma (26 patients, M:F =3D 11:15; age range, 16-61 (mean, 36,2) years), and 58 cases without chlesteatoma (56 patients, M:F =3D 25:31, age range, 15-61 (mean, 36.2) years). The findings of temporal bone CT were analysed at the point of bony changes including erosion and medial displacement of ossicles (malleus, incus, and stapes), erosion or destruction of the scutum, tegmen, facial canal, and lateral semicircular canal, and ballooning of the tympanic cavity and mastoid antrum. In addition, the soft tissue changes seen on temporal bone CT were analyzed at the site of lateral bulging of soft tissue in Prussak's space, perforation of the pars flaccida, tympanic membrane retraction, and tympanosclerosis. We retrospectively compared the findings of temporal bone CT with the surgical findings, and to assess statistical significance, the Chi-square test was used. Bone erosion or destruction was seen in 36.2% of COM cases without cholesteatoma, and in 96.2% of cases with cholesteatoma. Comparing COM with and without cholesteatoma, the erosion of ossicles including the malleus (81%, 24%), incus (88%, 14%), stapes (58%, 10%), scutum (88%, 10%), facial canal (8%, 0%), and lateral semicircular canal (8%, 0%), was more common in COM with cholesteatoma (p-value less than 0.05), with the exception of erosion of the tegmen (8%, 3%). Other bony changes including medial displacement of ossicles (27%, 3%), ballooning of tympanic cavity and mastoid antrum (96%, 16%), and the soft tissue changes including lateral bulging of soft tissue in Prussak's space (58%, 14%) and perforation of the pars flaccida (35

Differential diagnosis between chronic otitis media with and without cholesteatoma by temporal bone CT: focus on bone change and mass effect

Energy Technology Data Exchange (ETDEWEB)

Jung, Cheol Kyu; Park, Dong Woo; Seong, Jin Yong; Lee, Kak Soo; Park Choong Ki; Lee, Seung Ro; Hahm, Chang Kok [College of Medicine, Hanyang University, Seoul (Korea, Republic of)

2000-01-01

In order to determine specific differences, we compared the temporal bone CT findings of chronic otitis media (COM) with and without cholesteatoma, focusing on bone change. Between 1997 and 1998, 82 patients (84 cases) underwent temporal bone CT and were shown to have COM, with or without cholesteatoma after mastoidectomy and tympanoplasty. There were 36 cases of COM with cholesteatoma (26 patients, M:F =3D 11:15; age range, 16-61 (mean, 36,2) years), and 58 cases without chlesteatoma (56 patients, M:F =3D 25:31, age range, 15-61 (mean, 36.2) years). The findings of temporal bone CT were analysed at the point of bony changes including erosion and medial displacement of ossicles (malleus, incus, and stapes), erosion or destruction of the scutum, tegmen, facial canal, and lateral semicircular canal, and ballooning of the tympanic cavity and mastoid antrum. In addition, the soft tissue changes seen on temporal bone CT were analyzed at the site of lateral bulging of soft tissue in Prussak's space, perforation of the pars flaccida, tympanic membrane retraction, and tympanosclerosis. We retrospectively compared the findings of temporal bone CT with the surgical findings, and to assess statistical significance, the Chi-square test was used. Bone erosion or destruction was seen in 36.2% of COM cases without cholesteatoma, and in 96.2% of cases with cholesteatoma. Comparing COM with and without cholesteatoma, the erosion of ossicles including the malleus (81%, 24%), incus (88%, 14%), stapes (58%, 10%), scutum (88%, 10%), facial canal (8%, 0%), and lateral semicircular canal (8%, 0%), was more common in COM with cholesteatoma (p-value less than 0.05), with the exception of erosion of the tegmen (8%, 3%). Other bony changes including medial displacement of ossicles (27%, 3%), ballooning of tympanic cavity and mastoid antrum (96%, 16%), and the soft tissue changes including lateral bulging of soft tissue in Prussak's space (58%, 14%) and perforation of the pars

Cochlin-tomoprotein (CTP) detection test identified perilymph leakage preoperatively in revision stapes surgery.

Science.gov (United States)

Kataoka, Yuko; Ikezono, Tetsuo; Fukushima, Kunihiro; Yuen, Koji; Maeda, Yukihide; Sugaya, Akiko; Nishizaki, Kazunori

2013-08-01

Perilymphatic fistula (PLF) is defined as an abnormal leakage between perilymph from the labyrinth to the middle ear. Symptoms include hearing loss, tinnitus, and vertigo. The standard mode of PLF detection is intraoperative visualization of perilymph leakage and fistula, which ostensibly confirms the existence of PLF. Other possible methods of diagnosis include confirmation of pneumolabyrinth via diagnostic imaging. Recently, a cochlin-tomoprotein (CTP) detection test has been developed that allows definitive diagnosis of PLF-related hearing loss. We report the case of a 45-year-old man who presented with right-sided tinnitus, hearing loss, and dizziness 30 years after stapes surgery. Middle ear lavage was performed after myringotomy. A preoperative diagnosis of PLF was reached using the CTP detection test. Intraoperative observations included a necrotic long process of the incus, displaced wire piston, and fibrous tissue in the oval window. Perilymph leakage was not evident. The oval window was closed with fascia, and vertigo disappeared within 2 weeks postoperatively. When PLF is suspected after stapes surgery, the CTP detection test can be a useful, highly sensitive, and less invasive method for preoperative diagnosis. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Into the dark: patterns of middle ear adaptations in subterranean eulipotyphlan mammals

Science.gov (United States)

Koyabu, Daisuke; Hosojima, Misato; Endo, Hideki

2017-09-01

Evolution of the middle ear ossicles was a key innovation for mammals, enhancing the transmission of airborne sound. Radiation into various habitats from a terrestrial environment resulted in diversification of the auditory mechanisms among mammals. However, due to the paucity of phylogenetically controlled investigations, how middle ear traits have diversified with functional specialization remains unclear. In order to identify the respective patterns for various lifestyles and to gain insights into fossil forms, we employed a high-resolution tomography technique and compared the middle ear morphology of eulipotyphlan species (moles, shrews and hedgehogs), a group that has radiated into various environments, such as terrestrial, aquatic and subterranean habitats. Three-dimensional geometric morphometric analysis was conducted within a phylogenetically controlled framework. Quantitative shapes were found to strongly reflect the degree of subterranean lifestyle and weakly involve phylogeny. Our analyses demonstrate that subterranean adaptation should include a relatively shorter anterior process of the malleus, an enlarged incus, an enlarged stapes footplate and a reduction of the orbicular apophysis. These traits arguably allow improving low-frequency sound transmission at low frequencies and inhibiting the low-frequency noise which disturbs the subterranean animals in hearing airborne sounds.

Pre-operative computed tomography evaluation of congenital aural atresia in children; Bilan tomodensitometrique pre-operatoire des aplasies majeures de l`oreille chez l`enfant

Energy Technology Data Exchange (ETDEWEB)

Lumbroso, C.; Sebag, G.; Argyropoulou, M.; Manach, Y.; Lallemand, D. [Hopital Necker-Enfants-Malades, 75 - Paris (France)

1995-04-01

To describe computed tomography (CT) findings in congenital aural atresia (CAA) and to illustrate the impact of these findings in the preoperative evaluation. A narrow bony external auditory canal (EAC) was present in 24% of the cases. In one of these cases, the EAC contained a cholesteatoma and was consequently a clear indication of surgery. An hyperpneumatized mastoid (22%), a posterior position of the temporo mandibular joint (16%), and a bulging medial temporal fossa (12%) made the operation much more difficult. The tympanic cavity was small in 68% of the cases, normal in 28% and absent in 4% of the cases without any detectable ossicular chain. Ossicular chain anomalies were present in 91% of the cases. This consisted most frequently of a fusion of the malleus and the incus (76%) with or without fusion of the tympanic wall (33%). Lateral and anterior displacement of the descending portion of the facial nerve was present in 62%. Oval and round windows were normal in 86% of the cases. A soft tissue opacity (33%) in the tympanic cavity made it difficult to evaluate the stapes, the incudo stapedial articulation, and the facial nerve. Simultaneous abnormalities of inner ear were exceptional. (authors). 9 refs., 8 figs.

Dissection of the Auditory Bulla in Postnatal Mice: Isolation of the Middle Ear Bones and Histological Analysis.

Science.gov (United States)

Sakamoto, Ayako; Kuroda, Yukiko; Kanzaki, Sho; Matsuo, Koichi

2017-01-04

In most mammals, auditory ossicles in the middle ear, including the malleus, incus and stapes, are the smallest bones. In mice, a bony structure called the auditory bulla houses the ossicles, whereas the auditory capsule encloses the inner ear, namely the cochlea and semicircular canals. Murine ossicles are essential for hearing and thus of great interest to researchers in the field of otolaryngology, but their metabolism, development, and evolution are highly relevant to other fields. Altered bone metabolism can affect hearing function in adult mice, and various gene-deficient mice show changes in morphogenesis of auditory ossicles in utero. Although murine auditory ossicles are tiny, their manipulation is feasible if one understands their anatomical orientation and 3D structure. Here, we describe how to dissect the auditory bulla and capsule of postnatal mice and then isolate individual ossicles by removing part of the bulla. We also discuss how to embed the bulla and capsule in different orientations to generate paraffin or frozen sections suitable for preparation of longitudinal, horizontal, or frontal sections of the malleus. Finally, we enumerate anatomical differences between mouse and human auditory ossicles. These methods would be useful in analyzing pathological, developmental and evolutionary aspects of auditory ossicles and the middle ear in mice.

CT virtual endoscopy of the auditory ossicular chain and its preliminary clinical application

International Nuclear Information System (INIS)

Wang Dong; Zhang Wanshi; Xiong Minghui; Xu Jiaxing; Yu Min; Xu Changyu

2000-01-01

Objective: To evaluate the ability of CT virtual endoscopy (CTVE) in visualization of auditory ossicular chain and its clinical application. Methods: CTVE of auditory ossicular chain was performed on GE HiSpeed CT/i with 1.0 mm slice thickness at pitch 1.0, bone algorithm, 9.6 cm FOV, and 0.1 mm reconstruction interval in 10 normal subjects and 21 patients with middle ear diseases, 14 of them were proved by operation. The threshold values for normal and abnormal auditory ossicular chain were -600--200 HU and 50-300 HU respectively. Results: CTVE could clearly demonstrate the shape, size, and relation of the normal auditory ossicular chain. A visualization rate of malleus, incus, and incudomalleal articulation was 100%, and was 32% for the stapedial foot plate. However, in only 21% could the anterior and posterior crura of stapes be distinguished. Cholesteatoma was found in 12 cases with chronic otitis media, in which CTVE demonstrated varying degrees of destruction of the auditory ossicle. In 1 case with congenital anomaly, ossicle dysplasia was seen. Conclusion: CTVE being a new, non-invasive method for demonstrating the three-dimensional image of auditory ossicular chain is useful in evaluating diseases of the ear, especially the auditory ossicles

The signature of fusion between the embryological derivatives of the first and second branchial arches within the ossicular chain in MDCT

Directory of Open Access Journals (Sweden)

Sherif Abdelmonem Shama

2018-03-01

Full Text Available The embryological precursors of the ossicular chain of the middle ear in humans are still a matter of debate. Both classical interpretation and dual-arch interpretation are strong hypothesis. The Aim of the work was to use the MDCT in assessment of the sites of expected fusion between the embryological derivatives of the first and second branchial arches within the ossicular chain. This study was conducted on 200 normal ears. Results: The junctional zones were considered as near vertically oriented faint lines running within the malleous and incus in the axial MDCT cuts. Using fine manual manipulation of the scan planes and widow leveling, the presence of these junctional zones was confirmed in 174 sides (87%. Conclusions: The presence of the junctional zones between embryological derivatives of the first and second branchial arches within the ossicular chain at MDCT basis could support the dual arch interpretation at least in most of humans. Whatever the classical or dual arch interpretations or both are correct, the signature of such fusion between embryological derivatives of the first and second branchial arches within the ossicular chain, should be considered as normal variant and should not be mistaken with ossicular erosions, fractures or dislocations. Keywords: First branchial arch, Second branchial arch, Ossicular chain, MDCT

Response of the human tympanic membrane to transient acoustic and mechanical stimuli: Preliminary results

Science.gov (United States)

Razavi, Payam; Ravicz, Michael E.; Dobrev, Ivo; Cheng, Jeffrey Tao; Furlong, Cosme; Rosowski, John J.

2016-01-01

The response of the tympanic membrane (TM) to transient environmental sounds and the contributions of different parts of the TM to middle-ear sound transmission were investigated by measuring the TM response to global transients (acoustic clicks) and to local transients (mechanical impulses) applied to the umbo and various locations on the TM. A lightly-fixed human temporal bone was prepared by removing the ear canal, inner ear, and stapes, leaving the incus, malleus, and TM intact. Motion of nearly the entire TM was measured by a digital holography system with a high speed camera at a rate of 42 000 frames per second, giving a temporal resolution of <24 μs for the duration of the TM response. The entire TM responded nearly instantaneously to acoustic transient stimuli, though the peak displacement and decay time constant varied with location. With local mechanical transients, the TM responded first locally at the site of stimulation, and the response spread approximately symmetrically and circumferentially around the umbo and manubrium. Acoustic and mechanical transients provide distinct and complementary stimuli for the study of TM response. Spatial variations in decay and rate of spread of response imply local variations in TM stiffness, mass, and damping. PMID:26880098

Comparison of capacity for diagnosis and visuality of auditory ossicles at different scanning angles in the computed tomography of temporal bone

International Nuclear Information System (INIS)

Ogura, Akio; Nakayama, Yoshiki

1992-01-01

Computed tomographic (CT) scanning has made significant contributions to the diagnosis and evaluation of temporal bone lesions by the thin-section, high-resolution techniques. However, these techniques involve greater radiation exposure to the lens of patients. A mean was thus sought for reducing the radiation exposure at different scanning angles such as +15 degrees and -10 degrees to the Reid's base line. Purposes of this study were to measure radiation exposure to the lens using the two tomographic planes and to compare the ability to visualize auditory ossicles and labyrinthine structures. Visual evaluation of tomographic images on auditory ossicles was made by blinded methods using four rankings by six radiologists. The statistical significance of the intergroup difference in the visualization of tomographic planes was assessed for a significance level of 0.01. Thermoluminescent dosimeter chips were placed on the cornea of tissue equivalent to the skull phantom to evaluate radiation exposure for two separate tomographic planes. As the result, tomographic plane at an angle of -10 degrees to Reid's base line allowed better visualization than the other plane for the malleus, incus, facial nerve canal, and tuba auditiva (p<0.01). Scannings at an angle of -10 degrees to Reid's base line reduced radiation exposure to approximately one-fiftieth (1/50) that with the scans at the other angle. (author)

Sound pressure gain produced by the human middle ear.

Science.gov (United States)

Kurokawa, H; Goode, R L

1995-10-01

The acoustic function of the middle ear is to match sound passing from the low impedance of air to the high impedance of cochlear fluid. Little information is available on the actual middle ear pressure gain in human beings. This article describes experiments on middle ear pressure gain in six fresh human temporal bones. Stapes footplate displacement and phase were measured with a laser Doppler vibrometer before and after removal of the tympanic membrane, malleus, and incus. Acoustic insulation of the round window with clay was performed. Umbo displacement was also measured before tympanic membrane removal to assess baseline tympanic membrane function. The middle ear has its major gain in the lower frequencies, with a peak near 0.9 kHz. The mean gain was 23.0 dB below 1.0 kHz, the resonant frequency of the middle ear; the mean peak gain was 26.6 dB. Above 1.0 kHz, the second pressure gain decreased at a rate of -8.6 dB/octave, with a mean gain of 6.5 dB at 4.0 kHz. Only a small amount of gain was present above 7.0 kHz. Significant individual differences in pressure gain were found between ears that appeared related to variations in tympanic membrane function and not to variations in cochlear impedance.

A true minimally invasive approach for cochlear implantation: high accuracy in cranial base navigation through flat-panel-based volume computed tomography.

Science.gov (United States)

Majdani, Omid; Bartling, Soenke H; Leinung, Martin; Stöver, Timo; Lenarz, Minoo; Dullin, Christian; Lenarz, Thomas

2008-02-01

High-precision intraoperative navigation using high-resolution flat-panel volume computed tomography makes feasible the possibility of minimally invasive cochlear implant surgery, including cochleostomy. Conventional cochlear implant surgery is typically performed via mastoidectomy with facial recess to identify and avoid damage to vital anatomic landmarks. To accomplish this procedure via a minimally invasive approach--without performing mastoidectomy--in a precise fashion, image-guided technology is necessary. With such an approach, surgical time and expertise may be reduced, and hearing preservation may be improved. Flat-panel volume computed tomography was used to scan 4 human temporal bones. A drilling channel was planned preoperatively from the mastoid surface to the round window niche, providing a margin of safety to all functional important structures (e.g., facial nerve, chorda tympani, incus). Postoperatively, computed tomographic imaging and conventional surgical exploration of the drilled route to the cochlea were performed. All 4 specimens showed a cochleostomy located at the scala tympani anterior inferior to the round window. The chorda tympani was damaged in 1 specimen--this was preoperatively planned as a narrow facial recess was encountered. Using flat-panel volume computed tomography for image-guided surgical navigation, we were able to perform minimally invasive cochlear implant surgery defined as a narrow, single-channel mastoidotomy with cochleostomy. Although this finding is preliminary, it is technologically achievable.

Creation of a 3D printed temporal bone model from clinical CT data.

Science.gov (United States)

Cohen, Joss; Reyes, Samuel A

2015-01-01

Generate and describe the process of creating a 3D printed, rapid prototype temporal bone model from clinical quality CT images. We describe a technique to create an accurate, alterable, and reproducible rapid prototype temporal bone model using freely available software to segment clinical CT data and generate three different 3D models composed of ABS plastic. Each model was evaluated based on the appearance and size of anatomical structures and response to surgical drilling. Mastoid air cells had retained scaffolding material in the initial versions. This required modifying the model to allow drainage of the scaffolding material. External auditory canal dimensions were similar to those measured from the clinical data. Malleus, incus, oval window, round window, promontory, horizontal semicircular canal, and mastoid segment of the facial nerve canal were identified in all models. The stapes was only partially formed in two models and absent in the third. Qualitative feel of the ABS plastic was softer than bone. The pate produced by drilling was similar to bone dust when appropriate irrigation was used. We present a rapid prototype temporal bone model made based on clinical CT data using 3D printing technology. The model can be made quickly and inexpensively enough to have potential applications for educational training. Copyright © 2015 Elsevier Inc. All rights reserved.

Dynamic properties of human incudostapedial joint-Experimental measurement and finite element modeling.

Science.gov (United States)

Jiang, Shangyuan; Gan, Rong Z

2018-04-01

The incudostapedial joint (ISJ) is a synovial joint connecting the incus and stapes in the middle ear. Mechanical properties of the ISJ directly affect sound transmission from the tympanic membrane to the cochlea. However, how ISJ properties change with frequency has not been investigated. In this paper, we report the dynamic properties of the human ISJ measured in eight samples using a dynamic mechanical analyzer (DMA) for frequencies from 1 to 80 Hz at three temperatures of 5, 25 and 37 °C. The frequency-temperature superposition (FTS) principle was used to extrapolate the results to 8 kHz. The complex modulus of ISJ was measured with a mean storage modulus of 1.14 MPa at 1 Hz that increased to 3.01 MPa at 8 kHz, and a loss modulus that increased from 0.07 to 0.47 MPa. A 3-dimensional finite element (FE) model consisting of the articular cartilage, joint capsule and synovial fluid was then constructed to derive mechanical properties of ISJ components by matching the model results to experimental data. Modeling results showed that mechanical properties of the joint capsule and synovial fluid affected the dynamic behavior of the joint. This study contributes to a better understanding of the structure-function relationship of the ISJ for sound transmission. Copyright © 2018. Published by Elsevier Ltd.

Endoscopic versus transcranial procurement of allograft tympano-ossicular systems: a prospective double-blind randomized controlled audit.

Science.gov (United States)

Caremans, Jeroen; Hamans, Evert; Muylle, Ludo; Van de Heyning, Paul; Van Rompaey, Vincent

2016-06-01

Allograft tympano-ossicular systems (ATOS) have proven their use over many decades in tympanoplasty and reconstruction after resection of cholesteatoma. The transcranial bone plug technique has been used in the past 50 years to procure en bloc ATOS (tympanic membrane with malleus, incus and stapes attached). Recently, our group reported the feasibility of the endoscopic procurement technique. The aim of this study was to assess whether clinical outcome is equivalent in ATOS acquired by using the endoscopic procurement technique compared to ATOS acquired by using the transcranial technique. A double-blind randomized controlled audit was performed in a tertiary referral center in patients that underwent allograft tympanoplasty because of chronic otitis media with and without cholesteatoma. Allograft epithelialisation was evaluated at the short-term postoperative visit by microscopic examination. Failures were reported if reperforation was observed. Fifty patients underwent allograft tympanoplasty: 34 received endoscopically procured ATOS and 16 received transcranially procured ATOS. One failed case was observed, in the endoscopic procurement group. We did not observe a statistically significant difference between the two groups in failure rate. This study demonstrates equivalence of the clinical outcome of allograft tympanoplasty using either endoscopic or transcranial procured ATOS and therefore indicates that the endoscopic technique can be considered the new standard procurement technique. Especially because the endoscopic procurement technique has several advantages compared to the former transcranial procurement technique: it avoids risk of prion transmission and it is faster while lacking any noticeable incision.

[Applied anatomy of scala tympani inlet related to cochlear implantation].

Science.gov (United States)

Zou, Tuanming; Guo, Menghe; Zhang, Hongzheng; Shu, Fan; Xie, Nanping

2012-06-01

To investigate the related parameters of the temporal bone structure for determining the position of implanting electrode into the scala tympani in cochlear implantation surgery through the facial recess and epitympanum approach. In a surgical simulation experiment, 20 human temporal bones were studied and measured to determine the related parameters of the temporal bone structure. The distance 5.91∓0.29 mm between the short process of the incus and the round window niche, 2.11∓0.18 mm between the stapes and the round window niche, 6.70∓0.19 mm between the facial nerve in the perpendicular paragraph and the round window niche, 2.22∓0.21 mm from the pyramidal eminence to the round window, and 2.16∓0.14 mm between the stapes and the round window. The minimal distance between the implanting electrode and the vestibular window was 2.12∓0.19 mm. The distance between the cochleariform process and the round window niche was 3.79∓0.17 mm. The position of the cochlear electrode array insertion into the second cochlear turn was 2.25∓0.13 mm under the stapes. The location of the cochlear electrode array insertion into the second cochlear turn was 2.28∓0.20 mm inferior to the pyramidal eminence. These parameters provide a reference value to determine the different positions of cochlear electrode array insertion into the scale tympani in different patients.

Three dimensional CT of stapes. Stapedial imagings in dry temporal bone and clinical applications

Energy Technology Data Exchange (ETDEWEB)

Edamatsu, Hideo; Kubota, Osamu; Yamashita, Koichi [Kanazawa Medical Univ., Ishikawa (Japan)

1995-03-01

This study was performed to evaluate the usefulness and limitations of three dimensional (3-D) imagings of stapes in the middle ear by high speed helical CT. One dissected human temporal bone, ten normal and diseased ears were scanned with a slice of 1.0 mm and reconstructed in a thickness of 0.2-0.5 mm. Every specimen of 3-D can be observed in any plane and from any direction. Ossicular imagings of the temporal bone in 3-D were reconstructed as if the malleus, incus and stapes were observed under microscope. The whole structure of stapes was impossible to be represented by two dimensional CT heretofore in use, but 3-D in our study showed the head, crus and foot plate of the stapes in detail. Stapedial imagings of 3-D CT in normal ears showed the same findings as those recorded in temporal bone. Preoperative diagnostic findings of ossicles in the affected ears were very useful. Especially in ossicular anomalies, 3-D CT was positive in diagnosis and its accuracies were confirmed with operative observation. For the postoperative evaluation concerning the ossicular reconstruction, i.e. TORP and PORP, 3-D CT was also important method. It could present an anatomical relation between those prosthesis and the oval window. High speed helical CT can scan an object more quickly and clearly than formerly used CT, and its biological damage for human is less than that of the others. 3-D CT can be more clearly reconstructed with helical CT than former CT. (author).

Modeling of the incudo-malleolar joint within a biomechanical model of the human ear

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Ihrle, Sebastian; Eiber, Albrecht; Eberhard, Peter, E-mail: peter.eberhard@itm.uni-stuttgart.de [University of Stuttgart, Institute of Engineering and Computational Mechanics (Germany)

2017-04-15

Under large quasi-static loads, the incudo-malleolar joint (IM joint), connecting the malleus and the incus, is highly mobile. It can be classified as a mechanical filter decoupling large quasi-static motions while transferring small dynamic excitations. To investigate the influence of the behavior of the IM joint, a detailed simulation model of the IM-complex is created. Mathematical modeling of the IM joint behavior under quasi-static excitation requires adequate modeling of the mechanics of the diarthrodial joint. Therefore, the geometry of the articular surfaces, the ligaments, as well as their viscoelastic properties have to be included in the model. The contact of the articular surfaces is implemented using a penalty based contact formulation utilizing the geometric information obtained from micro computer tomography (micro-CT) scans. The ligaments of the joint capsule are modeled by distributing force elements along the joint capsule, with the position and orientation derived from the micro-CT scans. It is shown that the effects which were observed in measurements on human temporal bones are described adequately by the model, if the contact of the articular surfaces and the preload of the viscoelastic fibers are taken into account in the simulation model. In the following, the detailed model is implemented in an elastic multibody system of the entire ear. The model allows the study of different quasi-static load cases of the ossicles, such as it occurs in the reconstruction of the middle ear and form the basis for future simulative studies of sound transmission in natural or reconstructed ears.

Technical note: a landmark-based approach to the study of the ear ossicles using ultra-high-resolution X-ray computed tomography data.

Science.gov (United States)

Schmidt, Jodi L; Cole, Theodore M; Silcox, Mary T

2011-08-01

Previous study of the ear ossicles in Primates has demonstrated that they vary on both functional and phylogenetic bases. Such studies have generally employed two-dimensional linear measurements rather than three-dimensional data. The availability of Ultra- high-resolution X-ray computed tomography (UhrCT) has made it possible to accurately image the ossicles so that broadly accepted methodologies for acquiring and studying morphometric data can be applied. Using UhrCT data also allows for the ossicular chain to be studied in anatomical position, so that it is possible to consider the spatial and size relationships of all three bones. One issue impeding the morphometric study of the ear ossicles is a lack of broadly recognized landmarks. Distinguishing landmarks on the ossicles is difficult in part because there are only two areas of articulation in the ossicular chain, one of which (the malleus/incus articulation) has a complex three-dimensional form. A measurement error study is presented demonstrating that a suite of 16 landmarks can be precisely located on reconstructions of the ossicles from UhrCT data. Estimates of measurement error showed that most landmarks were highly replicable, with an average CV for associated interlandmark distances of less than 3%. The positions of these landmarks are chosen to reflect not only the overall shape of the bones in the chain and their relative positions, but also functional parameters. This study should provide a basis for further examination of the smallest bones in the body in three dimensions. Copyright © 2011 Wiley-Liss, Inc.

Modeling of the incudo-malleolar joint within a biomechanical model of the human ear

International Nuclear Information System (INIS)

Ihrle, Sebastian; Eiber, Albrecht; Eberhard, Peter

2017-01-01

Under large quasi-static loads, the incudo-malleolar joint (IM joint), connecting the malleus and the incus, is highly mobile. It can be classified as a mechanical filter decoupling large quasi-static motions while transferring small dynamic excitations. To investigate the influence of the behavior of the IM joint, a detailed simulation model of the IM-complex is created. Mathematical modeling of the IM joint behavior under quasi-static excitation requires adequate modeling of the mechanics of the diarthrodial joint. Therefore, the geometry of the articular surfaces, the ligaments, as well as their viscoelastic properties have to be included in the model. The contact of the articular surfaces is implemented using a penalty based contact formulation utilizing the geometric information obtained from micro computer tomography (micro-CT) scans. The ligaments of the joint capsule are modeled by distributing force elements along the joint capsule, with the position and orientation derived from the micro-CT scans. It is shown that the effects which were observed in measurements on human temporal bones are described adequately by the model, if the contact of the articular surfaces and the preload of the viscoelastic fibers are taken into account in the simulation model. In the following, the detailed model is implemented in an elastic multibody system of the entire ear. The model allows the study of different quasi-static load cases of the ossicles, such as it occurs in the reconstruction of the middle ear and form the basis for future simulative studies of sound transmission in natural or reconstructed ears.

Fate of Meckel's cartilage chondrocytes in ocular culture

International Nuclear Information System (INIS)

Richman, J.M.; Diewert, V.M.

1988-01-01

Modulation of the chondrocyte phenotype was observed in an organ culture system using Meckel's cartilage. First branchial arch cartilage was dissected from fetal rats of 16- and 17-day gestation. Perichondrium was mechanically removed, cartilage was split at the rostral process, and each half was grafted into the anterior chamber of an adult rat eye. The observed pattern of development in nonirradiated specimens was the following: hypertrophy of the rostral process and endochondral-type ossification, fibrous atrophy in the midsection, and mineralization of the malleus and incus. A change in matrix composition of the implanted cartilage was demonstrated with immunofluorescence staining for cartilage-specific proteoglycan (CSPG). After 15 days of culture, CSPG was found in the auricular process but not in the midsection or rostral process. In order to mark the implanted cells and follow their fate, cartilage was labeled in vitro with [3H]thymidine [3H]TdR). Immediately after labeling 20% of the chondrocytes contained [3H]TdR. After culturing for 5 days, 20% of the chondrocytes were still labeled and 10% of the osteogenic cells also contained radioactive label. The labeling index decreased in both cell types with increased duration of culture. Multinucleated clast-type cells did not contain label. Additional cartilages not labeled with [3H]TdR were exposed to between 20000 and 6000 rad of gamma irradiation before ocular implantation. Irradiated cartilage did not hypertrophy or form bone but a fibrous region developed in the midsection. Cells of the host animal were not induced to form bone around the irradiated cartilage. Our studies suggest that fully differentiated chondrocytes of Meckel's cartilage have the capacity to become osteocytes, osteoblasts, and fibroblasts

Middle ear implant in conductive and mixed congenital hearing loss in children.

Science.gov (United States)

Roman, Stéphane; Denoyelle, Françoise; Farinetti, Anne; Garabedian, Erea-Noel; Triglia, Jean-Michel

2012-12-01

Active middle ear implant can be used in children and adolescents with congenital hearing loss. The authors report their experience with the semi implantable Medel Vibrant Soundbridge(®) (VSB) in the audiologic rehabilitation of such patients. In this retrospective study, audiological and surgical data of 10 children (10.5±4 years) implanted with 12 VSB in 2 tertiary cares ENT Departments were analysed. Two children with bilateral external auditory canal (EAC) atresia and mixed hearing loss (mean air conduction (AC) thresholds=65dB HL) were bilaterally implanted. Eight children presented with microtia associated with EAC atresia bilaterally (n=3) and unilaterally (n=5). All of them had a conductive hearing loss in the implanted ear (mean (AC) thresholds were 58.75dB HL preoperatively). The Floating Mass Transducer was crimped on the long process of the incus (n=8) or on the suprastructure of the stapes (n=4). There were no intra- or postoperative surgical complications. All the children wore their implants after 5 weeks. Postoperative mean bone conduction (BC) thresholds were unchanged. The mean aided thresholds with VSB (four frequencies warble tones at 0.5, 1, 2 and 4 kHz) were 28dB HL (± 10). Word discrimination threshold in quiet conditions in free field with the VSB unilaterally activated was 50% at 38dB SPL (± 9). The results indicate that satisfaction of the children and their parents is very encouraging but surgeons should be cautious with this new approach in relation to the pinna reconstruction and to possible risks to inner ear and facial nerve. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Laser-assisted fixation of a nitinol stapes prosthesis.

Science.gov (United States)

Schrötzlmair, Florian; Suchan, Fabian; Pongratz, Thomas; Krause, Eike; Müller, Joachim; Sroka, Ronald

2018-02-01

Otosclerosis is an inner ear bone disease characterized by fixation of the stapes and consequently progressive hearing loss. One treatment option is the surgical replacement of the stapes by a prosthesis. When so called "smart materials" like nitinol are used, prosthesis fixation can be performed using a laser without manual crimping on the incus. However, specific laser-prosthesis interactions have not been described yet. The aim of the present study was to elucidate the thermo-mechanical properties of the NiTiBOND® prosthesis as a basis for handling instructions for laser-assisted prosthesis fixation. Closure of the NiTiBOND® prosthesis was induced ex vivo by either a diode laser emitting at λ = 940 nm or a CO 2 laser (λ = 10,600 nm). Total energy for closure was determined. Suitable laser parameters (pulse duration, power per pulse, distance between tip of the laser fiber and prosthesis) were assessed. Specific laser-prosthesis interactions were recorded. Especially the diode laser was found to be an appropriate energy source. A total energy deposit of 60 mJ by pulses in near contact application was found to be sufficient for prosthesis closure ex vivo. Energy should be transmitted through a laser fiber equipollent to the prosthesis band diameter. Specific deformation characteristics due to the zonal prosthesis composition have to be taken into account. NiTiBOND® stapes prosthesis can be closed by very little energy when appropriate energy sources like diode lasers are used, suggesting a relatively safe application in vivo. Lasers Surg. Med. 50:153-157, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

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

Science.gov (United States)

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.

Three dimensional volume rendering virtual endoscopy of the ossicles using a multi-row detector CT: applications and limitations

International Nuclear Information System (INIS)

Kim, Su Yeon; Choi, Sun Seob; Kang, Myung Jin; Shin, Tae Beom; Lee, Ki Nam; Kang, Myung Koo

2005-01-01

This study was conducted to know the applications and limitations of three dimensional volume rendering virtual endoscopy of the ossicles using a multi-row detector CT. This study examined 25 patients who underwent temporal bone CT using a 16-row detector CT as a result of hearing problems or trauma. The axial CT scan of the temporal bone was performed with a 0.6 mm collimation, and a reconstruction was carried out with a U70u sharp of kernel value, a 1 mm thickness and 0.5-1.0 mm increments. After observing the ossicles in the axial and coronal images, virtual endoscopy was performed using a three dimensional volume rendering technique with a threshold value of-500 HU. The intra-operative otoendoscopy was performed in 12 ears, and was compared with the virtual endoscopy findings. Virtual endoscopy of the 29 ears without hearing problems demonstrated hypoplastic or an incomplete depiction of the stapes superstructures in 25 ears and a normal depiction in 4 ears. Virtual endoscopy of 21 ears with hearing problems demonstrated no ossicles in 1 ears, no malleus in 3 ears, a malleoincudal subluxation in 6 ears, a dysplastic incus in 5 ears, an incudostapedial subluxation in 9 ears, dysplastic stapes in 2 ears, a hypoplastic or incomplete depiction of the stapes in 16 ears and no stapes in 1 ears. In contrast to the intra-operative otoendoscopy, 8 out of 12 ears showed a hypoplastic or deformed stapes in the virtual endoscopy. Volume rendering virtual endoscopy using a multi-row detector CT is an excellent method for evaluation the ossicles in three dimension, even thought the partial volume effect for the stapes superstructures needs to be considered

Ectopic Mineralization and Conductive Hearing Loss in Enpp1asj Mutant Mice, a New Model for Otitis Media and Tympanosclerosis.

Science.gov (United States)

Tian, Cong; Harris, Belinda S; Johnson, Kenneth R

2016-01-01

Otitis media (OM), inflammation of the middle ear, is a common cause of hearing loss in children and in patients with many different syndromic diseases. Studies of the human population and mouse models have revealed that OM is a multifactorial disease with many environmental and genetic contributing factors. Here, we report on otitis media-related hearing loss in asj (ages with stiffened joints) mutant mice, which bear a point mutation in the Enpp1 gene. Auditory-evoked brainstem response (ABR) measurements revealed that around 90% of the mutant mice (Enpp1asj/asj) tested had moderate to severe hearing impairment in at least one ear. The ABR thresholds were variable and generally elevated with age. We found otitis media with effusion (OME) in all of the hearing-impaired Enpp1asj/asj mice by anatomic and histological examinations. The volume and inflammatory cell content of the effusion varied among the asj mutant mice, but all mutants exhibited a thickened middle ear epithelium with fibrous polyps and more mucin-secreting goblet cells than controls. Other abnormalities observed in the Enpp1 mutant mice include over-ossification at the round window ridge, thickened and over-calcified stapedial artery, fusion of malleus and incus, and white patches on the inside of tympanic membrane, some of which are typical symptoms of tympanosclerosis. An excessive yellow discharge was detected in the outer ear canal of older asj mutant mice, with 100% penetrance by 5 months of age, and contributes to the progressive nature of the hearing loss. This is the first report of hearing loss and ear pathology associated with an Enpp1 mutation in mice. The Enpp1asj mutant mouse provides a new animal model for studying tympanosclerotic otitis and otitis media with effusion, and also provides a specific model for the hearing loss recently reported to be associated with human ENPP1 mutations causing generalized arterial calcification of infancy and hypophosphatemic rickets.

Congenital external auditory canal atresia and stenosis: temporal bone CT findings

Energy Technology Data Exchange (ETDEWEB)

Lee, Dong Hoon; Kim, Bum Soo; Jung, So Lyung; Kim, Young Joo; Chun, Ho Jong; Choi, Kyu Ho; Park, Shi Nae [College of Medicine, Catholic Univ. of Korea, Seoul (Korea, Republic of)

2002-04-01

To determine the computed tomographic (CT) findings of atresia and stenosis of the external auditory canal (EAC), and to describe associated abnormalities in surrounding structures. We retrospectively reviewed the axial and coronal CT images of the temporal bone in 15 patients (M:F=8:7;mean age, 15.8 years) with 16 cases of EAC atresia (unilateral n=11, bilateral n=1) and EAC stenosis (unilateral n=3). Associated abnormalities of the EAC, tympanic cavity, ossicles, mastoid air cells, eustachian tube, facial nerve course, mandibular condyle and condylar fossa, sigmoid sinus and jugular bulb, and the base of the middle cranial fossa were evaluated. Thirteen cases of bony EAC atresia (one bilateral), with an atretic bony plate, were noted, and one case of unilateral membranous atresia, in which a soft tissue the EAC. A unilateral lesion occurred more frequently on the right temporal bone (n=8, 73%). Associated abnormalities included a small tympanic cavity (n=8, 62%), decreased mastoid pneumatization (n=8, 62%), displacement of the mandibular condyle and the posterior wall of the condylar fossa (n=7, 54%), dilatation of the Eustachian tube (n=7, 54%), and inferior displacement of the temporal fossa base (n=8, 62%). Abnormalities of ossicles were noted in the malleolus (n=12, 92%), incus (n=10, 77%) and stapes (n=6, 46%). The course of the facial nerve was abnormal in four cases, and abnormality of the auditory canal was noted in one. Among three cases of EAC stenosis, ossicular aplasia was observed in one, and in another the location of the mandibular condyle and condylar fossa was abnormal. In the remaining case there was no associated abnormality. Atresia of the EAC is frequently accompanied by abnormalities of the middle ear cavity, ossicles, and adjacent structures other than the inner ear. For patients with atresia and stenosis of this canal, CT of the temporal bone is essentially helpful in evaluating these associated abnormalities.

Preoperative evaluation of the congenital aural atresia on computed tomography; an analysis of the severity of the deformity of the middle ear and mastoid

Energy Technology Data Exchange (ETDEWEB)

Tasar, Mustafa [Gulhane Medical School, Department of Radiology, Etlik-Ankara (Turkey)]. E-mail: tasarmus@yahoo.com; Yetiser, Sertac [Gulhane Medical School, Department of ORL and HNS (Turkey); Yildirim, Duzgun [Gulhane Medical School, Department of Radiology, Etlik-Ankara (Turkey); Bozlar, Ugur [Gulhane Medical School, Department of Radiology, Etlik-Ankara (Turkey); Tasar, M. Aysin [Ankara Hospital, Department of Pediatrics (Turkey); Saglam, Mutlu [Gulhane Medical School, Department of Radiology, Etlik-Ankara (Turkey); Ugurel, M. Sahin [Gulhane Medical School, Department of Radiology, Etlik-Ankara (Turkey); Battal, Bilal [Gulhane Medical School, Department of Radiology, Etlik-Ankara (Turkey); Ucoz, Taner [Gulhane Medical School, Department of Radiology, Etlik-Ankara (Turkey)

2007-04-15

Objective: To compare the development of temporal bone in normal and atretic ears and to assess some radiological landmarks that could be important in the hearing restoration interventions in such patients. Material and methods: Thirty-five patients with 40 atretic external ears were evaluated with temporal bone CT and compared to a control group of 40 normal ears retrospectively. Using comparable slice levels in all patients, the course and the caliper of the facial canal, the surface area of the incus and malleus, the level of mastoid aeration, the location and anteroposterior diameters of the jugular bulb and sigmoid sinus, the direction and the caliber of the tympanic bony part of the Eustachian tube, area of the middle ear cavity, distance from facial nerve to incudomalleolar joint, to the vestibule and to the jugular bulb were included in the assessment. Non-parametric and parametric statistical tests were used for comparison. Results: In atretic ears middle ear sectional area was found to be smaller at the equivalent plane as compared to control subjects (mean area index: 19.3 mm{sup 2} versus 47.4 mm{sup 2}). Mastoid aeration was low in general and the ossicles in the atretic ears were hypoplastic (mean ossicular sectional area: 8.3 mm{sup 2} versus 11 mm{sup 2}). The distance from the jugular bulb to the facial nerve was significantly lower (mean: 6.2 mm versus 6.8 mm) (p < 0.05) in the atretic ears. Facial canal caliber, distance from the facial canal to the incudomalleolar joint and distance from the facial canal to the vestibule in the atretic ears (means: 1.49, 2.93 and 1.82, respectively) did not show statistically significant difference from the control subjects (means: 1.44, 2.91 and 1.83, respectively) (p > 0.05 for all). Conclusion: External ear atresia is significantly associated with middle ear and mastoid abnormalities. The ossicles were underdeveloped which always have to be considered during reconstructive surgery. Radiologically, in the

Effects of middle ear quasi-static stiffness on sound transmission quantified by a novel 3-axis optical force sensor.

Science.gov (United States)

Dobrev, Ivo; Sim, Jae Hoon; Aqtashi, Baktash; Huber, Alexander M; Linder, Thomas; Röösli, Christof

2018-01-01

Intra-operative quantification of the ossicle mobility could provide valuable feedback for the current status of the patient's conductive hearing. However, current methods for evaluation of middle ear mobility are mostly limited to the surgeon's subjective impression through manual palpation of the ossicles. This study investigates how middle ear transfer function is affected by stapes quasi-static stiffness of the ossicular chain. The stiffness of the middle ear is induced by a) using a novel fiber-optic 3-axis force sensor to quantify the quasi-static stiffness of the middle ear, and b) by artificial reduction of stapes mobility due to drying of the middle ear. Middle ear transfer function, defined as the ratio of the stapes footplate velocity versus the ear canal sound pressure, was measured with a single point LDV in two conditions. First, a controlled palpation force was applied at the stapes head in two in-plane (superior-inferior or posterior-anterior) directions, and at the incus lenticular process near the incudostapedial joint in the piston (lateral-medial) direction with a novel 3-axis PalpEar force sensor (Sensoptic, Losone, Switzerland), while the corresponding quasi-static displacement of the contact point was measured via a 3-axis micrometer stage. The palpation force was applied sequentially, step-wise in the range of 0.1-20 gF (1-200 mN). Second, measurements were repeated with various stages of stapes fixation, simulated by pre-load on the stapes head or drying of the temporal bone, and with severe ossicle immobilization, simulated by gluing of the stapes footplate. Simulated stapes fixation (forced drying of 5-15 min) severely decreases (20-30 dB) the low frequency (4 kHz) response. Stapes immobilization (gluing of the footplate) severely reduces (20-40 dB) the low and mid frequency response (force (Force-displacement measurements around the incudostapedial joint showed quasi-static stiffness in the range of 200-500 N/m for normal middle

Conhecimento da anatomia da orelha de cobaias e ratos e sua aplicação na pesquisa otológica básica Understanding the anatomy of ears from guinea pigs and rats and its use in basic otologic research

Directory of Open Access Journals (Sweden)

Agnes Afrodite Sumarelli Albuquerque

2009-02-01

, two and half turns in the cochlea, and their tympanic membranes do not seal off the entire external auditory canal. Guinea pigs have full bullas, their incus and malleus are fused and they have three and half cochlear turns. Under SEM, guinea pigs and rats have Tectori Membrane, Raissner's Membrane and the Organ of Corti. Only guinea pigs have Hensen's Cells. CONCLUSION: Guinea pigs were considered easy to handle for microdissection purposes because of the size and robustness of their temporal bones, and for surgical experiments involving the stapes, the oval window and the tympanic membrane. Under SEM there are similarities guinea pigs and rats, and both can be used in inner ear studies.

Cirurgia revisional de 74 casos de estapedectomia/estapedotomia Revision surgery in 74 cases of stapedectomy/stapedotomy

Directory of Open Access Journals (Sweden)

Luiz Rogerio Pires de Mello

2003-01-01

postoperative results depend on the surgical pathology found, not only because of the presence or absence of the incus but also because of the osseous reobliteration of the oval window. CONCLUSION: Considering all revisionsurgery cases, the auditory gains obtained were the following: for 78.3% of the patients, the auditory threshold was as low as 20db, for 10.8% of the patients, it ranged from 20dB to 25dB, and for 8.2% of the patients, it was only above 25%; there was anacusis in 2.7% of the patients. The standard audiologic evaluation included pure tone threshold for air and bone conduction at 250, 500, 1000, 2000, 4000 and 8000Hz, speech recognition threshold and speech discrimination score. The PTA at 500, 1000 and 2000 was calculated for air and bone curves from both preoperative and postoperative audiograms.