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At least 19 recordsLinked to original sources
PubMed1993

Otoacoustic emissions in children with normal ears, middle ear dysfunction, and ventilating tubes.

The clinical utility of otoacoustic emissions (OAEs) has been well established in adults. The purpose of this investigation was to determine the efficacy of OAE testing in children. Distortion-product OAE (DPOAE) audiograms, response/growth functions, and transiently evoked OAEs elicited with clicks were measured from the ears of both healthy volunteers, aged 4 to 13 years, and children with confirmed middle ear disorders. These measures established the means and variabilities for DPOAE and noise-floor amplitudes of normal and diseased young ears. Compared with adult emissions, the healthy young ears exhibited greater mean DPOAE and noise-floor amplitudes. In contrast, ears with type B and type C tympanogram patterns showed absent or markedly reduced OAE amplitudes, when compared with emissions measured in their control counterparts. Finally, ears with ventilating tubes exhibited OAE amplitudes lower than amplitudes from healthy ears, but higher than those of the untreated diseased ears. Although these findings imply that using OAEs to test the outer hair-cell reserve of infected ears is problematic, emitted responses provide useful information concerning the normalcy of middle ear function.

Acoustic Impedance Tests↗
PubMed2003

Epithelial tumors of the middle ear--are middle ear carcinoids really distinct from middle ear adenomas?

Primary tumors of the middle ear are much less commonly encountered in clinical practice than non-neoplastic lesions such as inflammatory polyps (aural polyps) or cholesteatomas. The rarity of such tumors can complicate attempts, by both clinicians and pathologists, to correctly classify them. It has been customary for many authors to segregate middle ear adenomas (MEAs) from middle ear carcinoids as two discrete benign neoplastic entities. It has become apparent, however, that MEAs and carcinoids of the middle ear share a sufficient number of overlapping pathologic features and similarities of clinical behavior to warrant their collapse into a single diagnostic category. It is proposed that these tumors should be designated as MEAs, which are defined as benign, indolent epithelial tumors of the middle ear that do not invade or erode bone and do not metastasize. The individual tumor cells are cytologically bland and polygonal, columnar or plasmacytoid-shaped; they may be arranged in islands, glandular formations or trabeculae, but not in papillary structures. They are typically keratin- and vimentin-positive immunohistochemically, and are often positive as well with antibodies for chromogranin A, synaptophysin, neuron-specific enolase, Leu-7, serotonin, pancreatic polypeptide and S-100 protein. Dense core neurosecretory granules may be identifiable by electron microscopy. Conservative surgical excision is the treatment of choice, and local recurrence following complete excision is quite uncommon.

Adenoma↗
PubMed1975

Auditory systems of Heteromyidae: functional morphology and evolution of the middle ear.

Middle ears (515) from 26 species of the rodent family Heteromyidae - genera Dipodomys, Microdipodops, Perognathus, and Liomys - were studied both grossly and histologically, for qualitative and quantitative comparisons. Middle ear modifications characteristic of each genus are qualitatively described. Quantitative comparisons are made among the 26 species in the study. Some correlations between middle ear size and other measurements are discussed. The middle ear is an acoustical transformer that for best efficiency must match the impedance of the cochlea to the impedance of the air in the external auditory meatus. It accomplishes this by a pressure increase and a velocity decrease through the combined effects of the lever and areal ratios; however, because the important consideration is a matching of two impedances rather than an absolute pressure increase, the pressure transformer ratio is a less informative measure of the middle ear's efficiency than is the impedance transform ratio. The impedance transformer mechanism is explained (from a morphological point of view), and equations are presented. Dipodomys, Microdipodops, and Perognathus have a theoretical transmission (at the resonant frequency) of 94-100% of the incident acoustical energy; Liomys, 78-80%. The areal ratio of stapes footplate to 2/3 tympanic membrane is remarkably constant among the species, varying only from 0.04 to 0.07: in Dipodomys and Microdipodops this small ratio is due to the very large tympanic membrane; in Perognathus and Liomys it is due to the extremely small stapes footplate. The lever ratio of incus to malleus varies from 0.28 to 0.33 in Dipodpmys and Microdipodops, from 0.37 to 0.46 in Perognathus, and from 0.55 to 0.60 in Liomys. In addition, the middle ear volumes and the morphology of tympanic membrane, ossicles, ligaments, and muscles, all combine to minimize both mass and stiffness. All these data suggest middle ear mechanisms which are very efficient over a broad frequency range. The middle ear modifications found in heteromyids are adaptive in predator avoidance, especially in areas of little natural cover; nevertheless, contrary to expectations, there is no firm relationship between habitat and the extent of these modifications in the 26 species. However, environment did apparently plan an important role in the evolution of the family, and this is discussed.

Acoustics↗
PubMed1989

[The value of high-resolution computerized tomography in abnormalities of the middle ear].

Middle ear malformations are common congenital disorders of the head and neck area. Recent advances in plastic and middle ear surgery have improved the prognosis of patients suffering from congenital hearing disorders. However, sophisticated preoperative procedures are mandatory. The development of HR-CT has improved the radiologic possibilities to evaluate middle ear disorders significantly. In the present study we examined by means of HR-CT twenty patients with congenital middle ear malformation. Our findings include different sizes of the middle ear as well as dysplastic alterations of the malleus and incus. The inner ear was normal in almost all cases. Our results indicate that preoperative HR-CT is a reliable diagnostic method to demonstrate middle ear disorders.

Ear Ossicles↗
PubMed1984

Mucosal immunity of the middle ear.

Middle ears affected by otitis media with effusion provide mucosal immunity. However, the normal middle ear has a very poorly developed mucosal system. It can be said that the middle ear is a potential site of immunological activity during infection. The poor development of its immune system is considered one of the factors in the infection-proneness of the middle ear, which leads to otitis media with effusion.

Animals↗
PubMedDate not supplied

Surgery of the mastoid in ears with middle ear effusion.

It has been demonstrated that in most ears with middle ear effusion the mastoid air cells may be involved as well. The mucosal changes and the secretion extends into all cavities of the ear including the mastoid air cells. In most ears insertin of a ventilating tube through the tympanic membrane is adequate for proper aeration of the middle ear as well as of the mastoid air cell system. The draining usually stops and the mucosa gradually changes into its normal condition. In a small percentage of these, the ear will continue to drain and the mastoid will not clear up. Antibiotics and decongestants fail to cure the ear. Surgical intervention of the mastoid may be indicated in the rare cases where conventional treatment fails to control the condition. The aim of this report is to 1) focus attention to the fact that the mastoid is an integral part of the middle ear cavity; 2) discuss the pathogenesis in stubborn ears with middle ear effusion; and 3) demonstrate the surgical procedure commonly used in our department in order to reestablish aeration of the mastoid air cell system. Early recognition and proper treatment of ears with middle ear effusion will hopefully reduce the incidence of stubborn cases and also decrease the number of those cases which end up with chronic otitis media and cholesteatoma. It is hoped that the screening programs involving school and even preschool children, as well as new preventative programs, will diminish the frequency of cases which need extensive surgery as discussed in this paper.

Ear, Middle↗
PubMed1990

Cadaver middle ears as models for living ears: comparisons of middle ear input immittance.

In vitro measurements of the middle ear input immittance in temporal bones extracted from human cadavers were directly compared with similar in vivo measurements from clinically normal subjects. The results of this comparison indicate that most otoscopically normal unfixed cadaver ears have middle ear input immittances that are indistinguishable from those of live subjects in the 0.1- to 2-kHz range--as long as they have been kept from drying and the static pressures on either side of the tympanic membrane are equal. The effects of the middle ear muscles on the measured input immittance are generally small and the cadaver ears can be maintained in the frozen state for several months with little change. Tympanometry appears to be a reliable indicator of normal middle ear immittance. Cadaver middle ears are useful models of human middle ear function.

Acoustic Impedance Tests↗
PubMed1991

[A nicardipine-isoflurane combination in the microsurgery of the middle ear].

Middle ear microsurgery requires a bloodless operative field, achieved through deliberate hypotension techniques. The present work was designed to analyze the quality of the deliberate hypotension induced by the combination of isoflurane with nicardipine, an injectable calcium channel blocker. Eleven patients, ASA I, 10 minutes after induction of anaesthesia, received nicardipine as a bolus of 25 mg renewed every five minutes (maximum 4) and as a perfusion (5 mg/hour). The bloodless operative field was excellent in all cases with a 29.7% drop in arterial blood pressure after 15 minutes (heart rate: +22.3% after 25 min); values then remained stable until nicardipine was stopped; then hemodynamic data returned to the preanaesthetic values in 66 +/- 56 minutes. No side effect was registered. As a conclusion, deliberate hypotension induced by isoflurane--nicardipine combination provides good conditions for middle ear microsurgery.

Adult↗
PubMed2001

Eosinophils are activated in middle ear mucosa and middle ear effusion of patients with intractable otitis media associated with bronchial asthma.

BACKGROUND: Although patients with intractable otitis media associated with bronchial asthma have extensive accumulation of eosinophils in the middle ear mucosa and middle ear effusion, systematic histological and immunohistochemical studies have not been performed. OBJECTIVES: To clarify the pathogenesis of middle ear diseases, we carried out immunohistochemical studies on middle ear specimens, particularly focusing on the characteristics of accumulated eosinophils. METHODS: Middle ear specimens obtained from eight adult patients and from 17 controls were immunohistochemically stained using monoclonal antibodies against EG1, EG2, mast cell tryptase, IgA and IgE. The concentration of eosinophil cationic protein (ECP) in middle ear effusion samples was also measured. RESULTS: In the asthmatic patients, severe round-cell infiltration was observed in the submucosa and most of the EG1-positive cells were also EG2-positive. In the control patients, the mucosa showed a fibrotic change with a few inflammatory cells, and EG1- or EG2-positive cells were quite few. The expression of IgE was found not only on the surface of mast cells but also within the plasma cells in the asthmatic patients, and the number of IgE-positive cells was about twice as high as that of mast cells. A significantly higher concentration of ECP was noted in middle ear effusion obtained from the asthmatic patients than that from the control patients. CONCLUSION: Most of the eosinophils in the middle ear mucosa and middle ear effusion were activated, resulting in degranulation and release of ECP, and local IgE production occurs in the middle ear mucosa, indicating that the intractable inflammation is closely associated with IgE-mediated late phase response with eosinophil accumulation.

Adult↗
PubMedDate not supplied

[Ultrastructural aspects of cholesteatoma of the middle ear].

Middle ear cholesteatomas were intraoperatively obtained from 6 male patients and studied under light (L.M.), transmission (T.E.M.) and scanning (S.E.M.) electron microscopy. Cholesteatoma proved to be formed by keratinizing squamous epithelium, or matrix, and by connective tissue, chorion or perimatrix. With regard to the matrix, a progressive differentiation of cells belonging to the stratum germinativum could be observed towards spinosum, granulosum and corneum cells with formation of keratinized lamellae. Moreover, keratinocytes and Langerhans cells were found in the stratum spinosum. The perimatrix consisted of granulation tissue, or inflamed subepithelial connective tissue displaying inflammatory cells. Furthermore, the advancing front of cholesteatoma proved to be formed by lymphocytes and plasma cells, partially covered by respiratory type epithelium.

Adult↗
PubMedDate not supplied

[Angiogenesis in cholesteatoma of the middle ear].

Middle ear cholesteatoma is characterized by the presence of a keratinizing squamous epithelium with hyperproliferative features. Such growth can only be supported by abundant blood vessels. The presence and distribution of blood vessels in cholesteatoma was studied to determine the mechanisms responsible for its origin and maintenance. Cholesteatoma (n = 30) and retroauricular skin samples (n = 30) were studied with indirect immunoperoxidase and alkaline phosphatase anti-alkaline phosphatase methods. Antibodies were used to recognize endothelial cells (von Willebrand Factor VII), vascular basal membrane components (type VI collagen), intercellular adhesion molecules (ICAM-1, 1CAM-2), human histocompatibility antigen (HLA-II) as a marker for cellular activation, angiogenetic growth factors and their receptors (TGF-alpha and VEGF), lymphocytes (CD3), and macrophages (KiM8). The cholesteatoma stroma had numerous vessels with intact basal membrane. The vessel concentration was higher in regions with abundant macrophage infiltration. Perivascular cell infiltrates were positive for antibodies against angiogenetic factors and HLA-II. Endothelial cells had increased expression of intercellular adhesion molecules and angiogenetic growth factor receptors. These results confirm the presence of increased vascularization in cholesteatoma, which may play an important role in sustaining continuous abnormal growth.

Cell Adhesion Molecules↗
PubMed1993

Do magnesium infusions protect the inner ear during middle ear surgery? A randomized double blind study.

Joachims et al. recently demonstrated that magnesium was able to protect the inner ear during exposure to noise and fire arms. During middle ear surgery, the inner ear is subjected to noise from fraising and drilling. We saw fit, therefore, to conduct a random double blind study to establish whether magnesium infusions would protect the inner ear during middle ear surgery. We examined 80 patients (38 verum, 42 placebo). The verum patients received 10 mg/kg body weight magnesium 12 hours and 1 hour prior to operation. Plasma and red cell magnesium levels were measured pre-operatively and intra-operatively; they rose as expected. Post-operative auditory tests showed that magnesium had no tendency to prevent inner ear damage. Advocates of magnesium criticize the limited number of patients in our study as well as the administration of the magnesium substitute. In our opinion, however, it should be borne in mind when evaluating these findings that noise from drilling and fraising is only one factor among many which can induce inner ear injury during middle ear surgery.

Adult↗
PubMed1990

PO2 levels in middle ear effusions and middle ear mucosa.

We measured PO2 values in mucoid and serous middle ear effusions (M-MEE, S-MEE) and in the middle ear mucosa of patients with otitis media with effusion (OME) and compared these values with those obtained from patients with middle ear barotrauma (MEBT). The mean and S.D. values of PO2 in M-MEE, S-MEE and MEBT effusions were 28.9 +/- 11.3, 31.5 +/- 9.5 and 37.0 +/- 15.4 mmHg, respectively; the mean and S.D. values in mucosa were 27.1 +/- 11.9, 27.0 +/- 13.2 and 32.5 +/- 1.0 mmHg, respectively. In health, PO2 values in middle ear mucosa are regulated by its blood supply, oxygen solubility in blood and the blood-to-cavity partial pressure gradient of the gas. When the Eustachian tube (ET) function is severely impaired, PO2 values in the middle ear air cavity depend on the mucosal condition, though some studies have shown a lack of relationship between ET function and PO2 values. Our results show that PO2 values in MEBT are consistently higher than in OME, suggesting that the attributable factor could be a better ET function in MEBT.

Barotrauma↗
PubMed1989

[Relation between the level of involvement of the ear, the middle ear and the face in microtia].

Based on examination of 80 adult men with unilateral microtia the authors examined the relationship between the affection of the ear lobe, middle ear and face. The revealed significant relations were due solely to subjects with the most severe or with the slightest affection. Correlation coefficients therefore do not characterize relations in the majority of patients and their magnitude is influenced by the ratio of marginal variants of the anomaly in the group. The calculation of the relationship for the entire range of variation of the defect thus is useless. These findings may have a more general validity. They are consistent with the experimental evidence on a haematogenic origin of branchiogenic defects and assumptions derived from this hypothesis. Facial asymmetry is a prognostically important sign for the estimation of the extent of damage of the middle ear.

Adult↗
PubMedDate not supplied

Clearance of middle ear effusions and middle ear pressures.

Twenty-six children presenting bilateral secretory otitis media (SOM) had ventilating tubes inserted into both middle ears. Mucus was, however, aspirated only from one ear, the right side. The vast majority of ears right and left were seen to have cleared their effusion equally well regardless of whether they were aspirated on not. This experiment points toward the essential intactness of the mucociliary system and the patency of the lumen of the Eustachian tube in SOM. Promotion of middle ear clearance through ventilation, which reminds one of the second opening in a beer can, does obviously suggest the relief of some negative pressure. Direct manometric measurements of SOM middle pressure were performed in 41 ears showing negative pressure averaging --1.7 mm H2O, this range being two orders of magnitude less than tympanometric measurements. Normal ears did not have even such a small negative pressure. The validity of these direct manometric measurements was checked against a model of the middle ear. Tympanometry, which is a valid diagnostic tool, does indicate in all probability the presence of middle ear effusion due to its rheologic effects on the drum and ossicles rather than the measure of actual middle ear pressures. This is determined by the fact that direct needling of the middle ear, or even the insertion of a ventilating tube, did not change tympanometric values but aspiration of part of the effusion did: indeed the latter tended to bring manometry to normal values.

Child, Preschool↗
PubMed2001

[Evaluation of canal wall down tympanoplasty with canal reconstruction for draining ear with middle ear cholesteatoma].

OBJECTIVES: We studied the postoperative stability of canal wall down tympanoplasty with canal reconstruction for middle ear cholesteatoma with preoperative otorrhea. SUBJECTS AND METHODS: 155 ears with middle ear cholesteatoma treated with canal wall down tympanoplasty with canal reconstruction were evaluated retrospectively. A comparison was made between the group of 80 ears which showed otorrhea, preoperatively, and the group of 75 without preoperative otorrhea. Problems observed in the tympanic membrane or reconstructed external auditory canal were evaluated both at the postoperative initial stage and more than 1 year after surgery. Postoperative hearing prognosis was also studied. RESULTS: 1) In the postoperative initial stage, local infection and necrosis of materials for canal reconstruction were significantly more likely to be observed in ears with preoperative otorrhea. 2) In ears with postoperative local infection, necrosis of materials for canal reconstruction occurred more frequently, and the period until drying of the reconstructed external auditory canal was significantly extended. 3) No significant difference was seen in postoperative status of the tympanic membrane and reconstructed ear canal at least 1 year after surgery. 4) The presence of preoperative otorrhea had no influence on hearing prognosis. CONCLUSIONS: When canal wall down tympanoplasty with canal reconstruction is used for ears with preoperative otorrhea, careful attention should be paid to local treatment at the postoperative initial stage. However, no significant problem occurred in the outcome of preoperative ear draining at least 1 year after surgery.

Adolescent↗
PubMed1995

Dangerous angles and depths for middle ear and middle cranial fossa injury during arthroscopy of the temporomandibular joint.

PURPOSE: Several reports have suggested a risk of injury to the middle cranial fossa and middle ear during arthroscopic procedures in the superior joint space of the temporomandibular joint (TMJ). However, there has been no anatomic study of directions and distances of the TMJ from the posterior portal in relation to the risk of mandibular fossa injury. In this study, the angles and depths at which the risk is greatest for injury to the deepest point of the mandibular fossa (DP) and to the middle ear during arthroscopy were analyzed. MATERIALS AND METHODS: Three-dimensional measurements of 96 mandibular fossae in 48 dry skulls were made. RESULTS: It was found that the distance from the lateral rim of the fossa to DP and Hugier's canal was 9.50 +/- 2.07 mm and 17.04 +/- 3.09 mm, respectively. The most dangerous angle for DP injury in the Frankfort horizontal plane (FH plane) was an inclination of the instrument base of -8 degrees dorsad and 17 and 19 degrees caudad in the frontal plane. The most dangerous angle for Hugier's canal injury was a tilting of the instrument base of 15 degrees ventrad in the FH plane and -2 degrees craniad in the frontal plane. However, these values showed a wide range. CONCLUSION: It was concluded that great care must be exercised in manipulation of instruments near the DP and Hugier's canal to avoid injury to the middle ear or penetration into the middle cranial fossa.

Adolescent↗