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At least 19 recordsLinked to original sources
PubMedDate not supplied

Pulse volume recordings in outer ear canal in pulse synchronous tinnitus. A comparison between ears with Glomus tumour, serous otitis media, and normal ears.

With the aid of a volume flowmeter it is possible to record pulse synchromous volumetric changes in the outer ear canal. In 7 ears with glomus tumour in the tympanic cavity and in 5 with serous otitis media, such changes were larger than in 125 persons with a normal middle ear. By changing the ambient pressure in a pressure chamber and instructing the patients not to swallow, the drum can be pushed inward or outward. In all the cases of glomus tumour studied the pulse volumetric change was considerably affected when the drum was pushed inward or outward. In the normal patients the change was no change at all. This means that the pulse volume changes in normals are generated mainly by the vessels in the outer ear canal.

Adolescent↗
PubMed1976

Tissue reaction to middle ear prostheses: in vivo observation (rabbit ear lobe) of polyethylene tube, stainless steel wire and absorbable gelatin sponge used in middle ear surgery.

Over the past ten years, polyethylene tube, stainless steel wire and absorbable gelatin sponge have come to be used in middle ear surgery. A modified Williams' steel chamber with a transparent central area was embedded in a rabbit ear lobe surgically, and cross-sectioned polyethylene tube, stainless steel wire or absorbable gelatin sponge were inserted respectively. The in vivo tissue reaction to each of these installed materials was observed daily microscopically. Finally, in the case of both the cross-sectioned polyethylene tube and the stainless steel wire, the chambers were fixed with 10% formalin solution and the contents stained for histological study. The results were as follows: Absorbable gelatin sponge was absorbed completely by phagocytosis in 62 days. Polyethylene tube was encapsulated by a layer of fibroblasts by day 110 in one case and by day 140 in another case; these findings were confirmed histologically on day 110 and 281. Almost all the surface of the stainless steel wire was encapsulated by a layer consisting of giant cells, on which a dense fibrous layer was superimposed by day 82. It is concluded that polyethylene tube, stainless steel wire, and absorbable gelatin sponge should be well tolerated in middle ear surgery.

Absorption↗
PubMedDate not supplied

Long-term observation of ears with reduced middle ear pressure.

335 ears from 210 childred in which tympanometry initially indicated middle ear pressure less than or equal to -100 mm H2O or a flat tympanogram have been reinvestigated 3 years later. When the inital investigation was performed all children were 7 years old. The present study reveals that 25% of these ears still have middle ear pressure less than or equal to -100 mm H2O and 16% middle ear pressure less than or equal to -150 mm H2O. In normal material of the same age group 9% have middle ear pressure less than or equal to -100 mm H2O and 4% middle ear pressure less than or equal to -150 mm H2O. The study also reveals effusion in 10% of ears with normal screening audiograms. In ears with normal screening audiograms and middle ear pressure greater than or equal to -145 mm H2O effusion was found in 5% and in ears with abnormal screening audiograms and middle ear pressure less than or equal to -150 mm H2O effusion was found in 81%. As tympanometric criterion for otologist referral, middle ear pressure less than or equal to -150 mm H2O or a flat tympanogram is suggested. The inclusion of tympanometry in routine screening for middle ear pathology in children is recommended.

Acoustic Impedance Tests↗
PubMed1977

[Chronic mucous effusions of the middle ear and the influence on inner ear function (author's transl)].

Audiometric recordings of children suffering from chronic mucous effusion of the middle ear have revealed a statistically significant and permanent sensorineural hearing loss of high frequences. Attemps for mechanical or physical factors as explanation are not convincing. We believe that inner ear disturbances in chronic mucous effusion rise by direct intoxication of the basal turns of the cochlea caused by pathologic alterations of mucous membrane tissue. Certain substances like lysozymes or histamine are supposed to diffuse via round window membrane to the inner ear. On the other hand mucous effusion which fills the middle cavity prevents oxygen to diffuse from the middle ear to the inner ear. Maass et al. (1976) and Morgenstern (1977) clearly have shown that under physiological conditions oxygen tension in the perilymph of the basal cochlear turn partly depends on diffusion from the middle ear. The results of our clinical observations indicate that early diagnosis and prompt treatment is necessary to prevent permanent sensorineural hearing loss of high frequencies, especially in infants and children.

Audiometry↗
PubMed1979

Middle ear pressure following tympanoplasty for various middle ear diseases. Pressure related to follow-up period and retractions.

In 512 ears with various middle ear diseases, the middle ear pressure was measured a minimum of 2 years and a maximum of 10 years after tympanoplasty. The findings were related to the length of the follow-up period and to retractions of the drum and/or in the epitympanum. The tympanometric findings were best in sequelae to otitis with dry perforations, poorest in cholesteatomas and adhesive otitis. Tubal function had not further deteriorated 4 years after the operation. There was a highly significant correlation between the middle ear pressure and the frequency of retractions, which also does not essentially increase--except in the cholesteatoma cases.

Acoustic Impedance Tests↗
PubMed1975

[Experimental changes of the pH in the middle ear and its effect on the internal ear (author's transl)].

Irrespective of their highly differing pH-value many pharmaca are nowadays applied to the middle ear. Animal experiments are to answer the question, weather changes in the pH-value of the middle ear may cause internal ear damages, With local application of different buffers (2.3-9.1 pH) into the tympanic cavity, the membrane of the round window was examined by means of the surface preparation technique, the pH-value of the perilymph was measured and the hair cells of the organ of corti were counted and histologically evaluated. With the reduction of the pH-value in the middle ear from 4.0 to 2.3 an increasing damage of the round window membrane could be detected. The pH-value of the perilymph, however, showed only a slight statistical variation, which cannot be guaranteed. After multiple applications of extremely acid buffers into the tympanic cavity directly before the round window membrane, a small but statistically significant reduction in the pH-value of the perilymph could be noticed. Hair cell damages at the organ of corti could in no case be observed.

Administration, Topical↗
PubMed1975

Middle ear mucosa and chronic ear disease. III. Enzyme studies of thick noncholesteatomous epithelium.

Thick mucosa removed from the promontory in cases with chronic otitis media showed prominent PAS-positive glands and epithelial secretory cells. Alcian blue positivity was less pronounced, contrary to the mucosa from glue ears. Enzyme activity in the epithelium and propria was comparable to that in glue ears, with some increase in alkaline phosphatase and some decrease in proprial lactate dehydrogenase and malate dehydrogenase activity. Removal of thick, permanently altered mucoas is recommended even in the absence of squamous epithelium. Steps should be taken to allow regrowth of thin, normal middle ear epithelium on the promontory.

Acid Phosphatase↗
PubMed1978

[A pilot study of sulfur hexa fluoride (sf6) injection into middle ears. An alternative to prevent atelectatic ears (author's transl)].

A new method to prevent middle ear atelectasis is presented. Sulfur Hexa Fluoride (SF6), a synthetic inert gas with a very low water solubility, has been injected into the middle ears of two patients with a long-standing conductive hearing loss due to nasopharyngeal carcinoma. The hearing gain expressed as lowered air-bone gaps lasted 6--10 weeks. No side effects were noted. In a later serie children with serous otitis media will be treated in the same way and followed with tympanograms and gas analyses of the gas mixture within their middle ears.

Age Factors↗
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↗
PubMedDate not supplied

Effects of middle ear pressure on the inner ear.

It was demonstrated in experiments on normal subjects that moderate ambient pressure changes, creating overpressure in the middle ear, may induce a vestibular reaction. In other experiments on subjects suffering from acute attacks of Meniere's disease, relief of symptoms was achieved by means of ambient pressure changes of the same magnitude.

Ear, Inner↗
PubMed1976

[The effect of ear surgery to the immunologic defense system of the middle ear during chronic otitis media (author's transl)].

Alpha-1-antitrypsin and alpha-2-macroglobuline are very important proteinase inhibitors for the healing process in chronic otitis media, because they can inhibit numerous bacterial and leukocytic proteinases: Alpha-2-macroglobuline can block the malignant proteinases of pseudomonas aeruginosa, staphylococcus aureus and proteus vulgaris. In 58 cases in the middle ear secretion was examined and the level of alpha-1-antitrypsin and alpha-2-macroglobulin investigated pre- and postoperatively. By these investigations we could demonstrate that the postoperative level of these two inhibitors is higher than preoperatively. In a couple of cases with cholesteatoma the postoperative concentration of alpha-2-macroglobuline was nearly three times higher than prior to the tympanoplasty. We believe that one of the causes for this high inhibitor level is the liberation of alpha-2-macroglobuline by injuring blood vessels during a tympanoplasty. It is our opinion that the increase of the inhibitor level in the postoperative phase is one of the prerequisites for the healing process in chronic otitis media.

Antibody Formation↗
PubMed1977

[A proposition for mutual genesis of hearing loss, recruitment and ear murmurs in the case of acute inner ear alterations (author's transl)].

Pathological changes on the stereocilia of cochlear hair cells observed by Bredberg et al. (1972) after noise exposure and in the early stages of antibiotic intoxication are suggested to cause a mechanical decoupling between the tectorial membrane and the hair cells. During acute episodes of endolymphatic hydrops a similar decoupling is suggested to occur, although for different reasons. Harris (1968) calculated the noise generated at the input to the hair cells on account of the Brownian motion of air particles in front of the tympanic membrane. For tight coupling, he obtained a level of (--)22 dB re auditory threshold. For loose coupling this noise was found to increase to +33 dB, i.e., for 55 dB. These two independent findings are used to account for the combination of hearing loss, recruitment, and tinnitus observed with the inner-ear pathologies mentioned. The proposed hypothesis is in good agreement with clinical observations.

Anti-Bacterial Agents↗