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At least 19 recordsLinked to original sources
PubMed1992

The evaluation of ear canal, middle ear, temporal bone, and cerebellopontine angle masses in infants, children, and adolescents.

Ear canal, middle ear, temporal bone, and CPA angle masses (except for cholesteatomas) are rare in the pediatric population. The physician needs to have a high degree of suspicion for such lesions if a child presents with ear pain unrelated to infection or otorrhea that fails to improve after treatment. A precise diagnosis needs to be made in these children and also in those with hearing loss, vertigo, and facial paralysis. The most useful imaging procedures for ear, temporal bone, and CPA masses are CT and MR imaging. With a suspected vascular lesion, a definitive diagnosis usually can be made by an imaging procedure or angiography. In all cases of mass lesions, except for some aneurysms and infections, a tissue diagnosis must be secured.

Adolescent↗
PubMed1998

Microbial flora and antimicrobial susceptibility patterns of isolated pathogens from the horizontal ear canal and middle ear in dogs with otitis media.

OBJECTIVE: To compare microbial flora and antimicrobial susceptibility patterns of isolated pathogens from the horizontal ear canal and middle ear in dogs with otitis media. DESIGN: Prospective study. ANIMALS: 23 dogs with chronic bilateral otitis externa. PROCEDURES: Swab specimens of the horizontal ear canal and middle ear were obtained for cytologic analysis, bacterial culture, and antimicrobial susceptibility testing. Integrity of the tympanic membrane was observed. If the tympanic membrane was intact, myringotomy was performed to collect specimens. RESULTS: Otitis media was diagnosed in 38 of 46 (82.6%) ears evaluated. The tympanic membrane was intact in 71.1% of the ears with otitis media. The 3 most common organisms isolated from the horizontal ear canal and middle ear were Staphylococcus intermedius, yeast, and Pseudomonas spp. A difference in total isolates or susceptibility patterns between the horizontal ear canal and middle ear was found in 34 (89.5%) ears. Compared with results of bacterial culture, cytologic examination of swab specimens was not as effective for detection of rods and cocci from the middle ear. CLINICAL IMPLICATIONS: In dogs with chronic otitis externa, otitis media often exists even when there is an intact tympanic membrane. In our study, the same isolates were rarely found in the horizontal ear canal and middle ear. Therefore, to choose appropriate antimicrobial agents, in addition to cytologic examination, bacterial culture and susceptibility testing of swab specimens from the horizontal ear canal and middle ear should be performed.

Animals↗
PubMed1988

Serous otitis media (S.O.M.). A bacteriological study of the ear canal and the middle ear.

A bacteriological study of the middle-ear effusions and the ear canals in children with chronic serous otitis media (S.O.M.) was performed. Sixty-eight children (127 ears) were investigated. From this study it appeared that cleansing of the ear canal with 0.5% chlorhexidine in 70% ethanol for 30 s is partially effective; micro-organisms (diptheroids, Staphylococcus epidermidis) could still be isolated in 29%. Cleansing of the ear canal decreases the incidence of middle-ear fluid contamination by non-pathogenic ear canal organisms (diptheroids, Staphylococcus epidermidis, Aerococcus), but after cleansing, 'non-pathogenic' micro-organisms could still be isolated in 33% of the effusions (diptheroids, Staphylococcus epidermidis). From 12% of the middle-ear effusions pathogenic micro-organisms (Hemophilus influenzae, Staphylococcus pneumoniae) were isolated; cleansing of the ear canal did not influence this percentage. Anaerobics were not isolated from the middle-ear effusions.

Adolescent↗
PubMed1988

Pressure transmission properties from the externa ear canal to the inner ear. An experimental study using guinea pigs.

The inner ear pressure (PIE) in response to pressure changes in the external ear canal was measured in guinea pigs while alternatively opening and closing the perforation of the otic bulla. When the bulla was opened, only a transient degree of applied pressure was transmitted to the inner ear and the amplitude of the PIE was smaller than that of the corresponding PIE when the bulla was closed. This was because the applied pressure was exclusively transmitted to the inner ear via the ossicular chain. When the otic bulla was closed, the pressure was transmitted not only via the ossicular chain but also via the round window (RW) through the middle ear cavity. When the bulla was closed, the amplitude of PIE was larger by a positive pressure load than by the corresponding negative one. The amplitude of PIE showed a linear relationship to ear canal pressure of at least within the +/- 200 mmH2O range, as long as pressure was slowly applied to the ear canal. When the loading pressure was abruptly changed, a bouncing response, possibly reflecting elasticity of the RW, was evoked, which diminished or disappeared when the round window was artificially ruptured.

Acoustic Impedance Tests↗
PubMed2001

[Carcinoma of the external ear canal and middle ear as interdisciplinary challenge for ear surgery and radiotherapy].

BACKGROUND: Carcinoma of the external auditory canal are tumours considered to have a poor prognosis. Improvement of the survival rate by surgical means alone is not possible. Individual therapy modalities as a result of an interdisciplinary approach between otosurgeon and radiotherapist are necessary. PATIENTS AND METHODS: A series of 30 patients (3 patients pretreated at other institutions) with carcinoma of the external auditory canal and middle ear treated between 1978 and 1997 in our institutions was analysed with particular reference to tumour size and its relation to surrounding tissues, patterns of neck node involvement, surgical procedures, and radiation techniques. Clinical endpoints were freedom from local failure, overall survival, disease-free survival. The mean follow-up was 4.7 years (range: 0.1 to 18.8 years), median 3 years. RESULTS: Treatment by surgery and radiotherapy resulted in an overall 5-year survival rate of 51%. According to Pittsburgh classification the 5-year survival rate for early disease (T1- and T2-tumours) was 89%, for stage III 67% and for stage IV 39%. Most important prognostic factors were dural infiltration (all patients with dural invasion died within 2.2 years) and the infiltration of surgical margins (the 5-year survival rate of patients with complete tumour resection was 100%, but 54% in patients with tumour beyond surgical margins). 192-iridium HDR afterloading brachytherapy based on 3D CT-treatment planning is an effective tool in the management of local recurrences following surgery and a full course of external beam radiotherapy. CONCLUSIONS: Surgical resection followed by radiotherapy adapted to the stage of disease and grade of resection is the preferred treatment of cancer of the external auditory canal and middle ear.

Adult↗
PubMed1995

[Effect size on resonance of the outer ear canal by simulation of middle ear lesions using a temporal bone preparation].

By means of a model of the external and the middle ear it is possible to simulate various, exactly defined pathological conditions of the middle ear and to describe their influence on ear canal resonance. Starting point of the investigations are fresh postmortem preparations of 8 human temporal bones with an intact ear drum and a retained skin of the ear canal. The compliance of the middle ear does not significantly differ from the clinical data of probands with healthy ears. After antrotomy it is possible to simulate pathological conditions of the middle ear one after the other at the same temporal bone. The influence of the changed middle ear conditions on ear drum compliance, ear canal volume and on the resonance curve of the external ear canal was investigated. For example, the middle ear was filled with water to create approximately the same conditions as in acute serous otitis media. In this middle ear condition a significant increase of the sound pressure amplification was found, on an average by 4 decibels compared to the unchanged temporal bone model. A small increase in resonance frequency was also measured. The advantages of this model are the approximately physiological conditions and the constant dimensions of the external and middle ear.

Acoustic Impedance Tests↗
PubMed1977

Ear canal hyperostosis--surfer's ear. An improved surgical technique.

The increased populatiry of surfing has produced a marked augmentation in the incidence of ear canal exostosis. However, when it becomes moderately severe, I prefer to call it "hyperostosis." Exposure to cold ocean water for many years can be an important etiologic factor in hyperostosis. There is a serious risk, and a high incidence of tympanic membrane perforations during the removal of large external canal hyperostosis. This injury can be prevented by placing a sheet of Silastic against the tympanic membrane beforehand. I describe the method. Serious degrees of hyperostosis, causing transient hearing loss and otitis externa, are increasingly common in coastal towns, where cold-water surfing is a popular year-around sport.

Adult↗
PubMed1997

Multifrequency tympanometry: effects of ear canal volume compensation on middle ear resonance.

Sweep frequency tympanograms compensating for ear canal volume at 200 and -400 daPa were obtained on 106 ears of 53 subjects during four different sessions. Resonance frequencies were obtained and analyzed to determine normative data, resonance differences between the compensation methods, and the interaction effect of running consecutive tympanograms. There were no gender or interaural differences for either compensation method. Although statistically significant, the compensation method by order interaction found between the first and second runs of tympanograms was not clinically significant. Compensation at 200 daPa was recommended when using sweep frequency tympanometry. Mean resonance frequency difference of the two compensation methods was 400 Hz. Large intersubject variability emphasized the need for audiologists to use proper compensation norms when examining middle ear resonance.

Acoustic Impedance Tests↗
PubMed1986

External ear canal cholesteatoma.

External ear canal cholesteatoma (EECC) is a rare otologic entity. Erosion of the inferior canal wall and accumulation of keratin debris are consistent findings. In the past there had been confusion between EECC and keratosis obturans, and they were thought to represent the same disease process. Currently, based on clinical and pathologic findings, it is believed that they are two different entities. In this article we present our experience in treating eight patients with EECC. For limited lesions, local debridement and curettage of necrotic bone is effective management. For more extensive lesions, canalplasty or tympanomastoidectomy is indicated.

Adult↗
PubMed1997

An improved method for the recovery of mycoplasmas from the external ear canal of goats.

The efficacy of ear canal flushing and ear canal and mouth swabbing methods for the isolation of mycoplasmas was investigated in 39 goats. Of the 19 goats positive for Mycoplasma spp., 14 (73.7%) were positive with the ear canal flushing method, 4 (21.0%) were positive with both ear canal flushing and mouth swabbing methods, and 1 (5.3%) was positive by the mouth swabbing method. Mycoplasma arginini, M. mycoides subsp. mycoides, and M. mycoides subsp. capri were identified by direct immunofluorescence and growth inhibition tests. Previous reports on the isolation of M. arginini from the ear canal of goats were not found in the literature.

Animals↗