PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “TENSOR TYMPANI”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 127 records · Page 7Linked to original sources

Narcolepsy with tinnitus aura: interpretation.

A fifty-five year old man was admitted to our ward for evaluation of narcoleptic-cataplectic attacks which were signaled by a "hissing sound like high pressure steam leaking out of a pipe." This tinnitus was exclusively localized to the right ear. It started about sixty-to-ninety seconds before the cataplectic episode (affecting mostly the jaw muscles) and lasted through part of it as it became progressively louder toward the end and ceased abruptly. It is postulated that, along with the collapse of tonic musculature of the mandible, a decrease of proprioceptive tone also affected the tensor tympani muscle leaving the middle ear vulnerable to internally generated noise. We further postulate that tinnitus was finally arrested by the generation of phasic bursts of contraction of the tensor tympani and/or the stapedius muscle at a later stage of cataplexy.

Electroencephalography↗

Ganglia and ganglion cells in the middle ear of the cat: preliminary report.

Twenty-five temporal bones of cats were studied for the presence of ganglia and/or ganglion cells in the middle ear. These structures were found at the following three main locations: (1) the promontory wall, both anterior to and below the stapes; (2) the capsule of the musculus tensor tympani, proximal, medial, and lateral to muscle fibers; and (3) the vertical portion of the facial nerve. To the best of our knowledge, ganglion cells in the capsule of the musculus tensor tympani, which is located proximal and lateral to the muscle fibers, have not been described previously.

Animals↗

[Degenerative changes in stapedius muscle morphology caused by aging].

Degenerative changes in the morphology of the stapedius muscle caused by aging using a collection of human temporal bones obtained by our department. The diameter of the muscle fibers, the variance in muscle fiber diameter, the ratios of intermuscular connective tissue and muscle to the area of the bone niche for the stapedius muscle, the number of muscle fibers around the tendon, and the adipose cell count were measured for each temporal bone. In total, 80 temporal bones were examined, excluding specimens with facial nerve degeneration, degenerative diseases, middle ear disease and leukemia. Between the ages of 38 fetal weeks and 9 years, the muscle fibers and thin and the variance in fiber diameter is small. The areas of intermuscular connective tissue, muscle and the number of muscle fibers around the tendon do not change between 38 fetal weeks and 60 years. All of the parameters measured showed no significant changes between the ages of 10 and 60 years. The variance in muscle fiber diameter began to increase in specimens aged 70 years or older because some of the muscle fibers had begun to atrophy. Adipose cells were sometimes observed in very old specimens. In contrast to the tensor tympani muscle, in which degenerative changes begin during childhood, atrophic degeneration of the stapedius muscle as a result of aging begins at a very late age. The difference in aging between the stapedius muscle and the tensor tympani muscle is probably related to evidence suggesting that the stapedius muscle contracts in response to acoustic stimulation.

Adolescent↗

Evolution of the middle ear apparatus in Talpid moles.

The middle ear structures of eight species of mole in the family Talpidae (Mammalia: Eulipotyphla) were studied under light and electron microscopy. Neurotrichus, Parascalops, and Condylura have a simple middle ear cavity with a loose ectotympanic bone, ossicles of a "microtype" morphology, and they retain a small tensor tympani muscle. These characteristics are ancestral for talpid moles. Talpa, Scalopus, Scapanus, and Parascaptor species, on the other hand, have a looser articulation between malleus and ectotympanic bone and a reduced or absent orbicular apophysis. These species lack a tensor tympani muscle, possess complete bullae, and extensions of the middle ear cavity pneumatize the surrounding basicranial bones. The two middle ear cavities communicate in Talpa, Scapanus, and Parascaptor species. Parascaptor has a hypertrophied malleus, a feature shared with Scaptochirus but not found in any other talpid genus. Differences in middle ear morphology within members of the Talpidae are correlated with lifestyle. The species with middle ears closer to the ancestral type spend more time above ground, where they will be exposed to high-frequency sound: their middle ears appear suited for transmission of high frequencies. The species with derived middle ear morphologies are more exclusively subterranean. Some of the derived features of their middle ears potentially improve low-frequency hearing, while others may reduce the transmission of bone-conducted noise. By contrast, the unusual middle ear apparatus of Parascaptor, which exhibits striking similarities to that of golden moles, probably augments seismic sensitivity by inertial bone conduction.

Animals↗

Effect of middle ear components on eardrum quasi-static deformation.

Eardrum deformation induced by quasi-static middle ear pressure was studied at progressive stages of dissection of gerbil temporal bones. With our high resolution moiré interferometer we recorded the shape and deformation of the eardrum along a line perpendicular to the manubrium and through the umbo, at different middle ear pressures. The deformation was measured from the medial side, after serially removing the cochlea, removing the stapes, cutting the tensor tympani, exposing the incudo-mallear joint, and cutting the anterior bony process which connects the malleus to the tympanic bone. The mean displacement as a function of pressure was also determined at all stages of dissection. Removing the cochlea and stapes, and cutting tensor tympani has no effect on static eardrum deformation. Exposing the incudo-mallear joint increases eardrum movement, and cutting the anterior bony connection between malleus and temporal bone strongly changes eardrum rest position and further increases its displacement.

Animals↗

Enzymes of transmitter and energy metabolism in rat middle ear and extraocular muscles.

To further investigate the peculiar characteristics of the middle ear and extraocular muscles, compared to the extensively studied skeletal muscles of the limbs, activities of enzymes of transmitter and energy metabolism were measured in homogenates of these muscles from albino and pigmented rats. These activities were compared to those for a masticatory muscle and for three hindlimb muscles chosen for their preponderance of either slow oxidative, fast glycolytic, or fast oxidative glycolytic fibers. Activities of the neuromuscular transmitter enzymes choline acetyltransferase and acetylcholinesterase were relatively very high in the extraocular and middle ear muscles. The activity of malate dehydrogenase, an enzyme of oxidative energy metabolism, was as high in the extraocular, masticatory and stapedius muscles as in the oxidative hindlimb muscles, but was lower in tensor tympani. The activity of lactate dehydrogenase, an enzyme of glycolytic energy metabolism, was remarkably low in both middle ear muscles. The results are consistent with high innervation density in the extraocular and middle ear muscles, and highly oxidative metabolism in the extraocular and stapedius muscles. Metabolic differences between the stapedius and tensor tympani suggest a relatively more active role for the former in the function of the rat middle ear.

Animals↗

Middle ear reflex activity in the startle reaction.

By means of extratympanic phonometry, the middle ear muscular reflex activity in the startle reaction was measured in a control series, in patients with otosclerosis and in patients with operation cavaties without a functioning tensor tympani muscle. In comparison with the stapedius reflex, the startle reflex was found to be much more variable regarding latency, amplitude, and configuration. It was characterized by pronounced fatigue and a high alertness dependence. The period of latency was about 60 msec. It was possible to elicit a distinct startle reflex in operation cavities without a functioning tensor tympani muscle, probably because of contraction of the Eustachian tube muscles.

Attention↗

How can the hooded seal dive to a depth of 1000 m without rupturing its tympanic membrane? A morphological and functional study.

Recent studies using a satellite-linked dive recorder have shown that the hooded seal (Cystophora cristata), a common Arctic pinniped, can dive to a depth of > 1000 m and stay submerged for close to 1 h. At these depths the water pressure reaches 100 atm, entailing obvious risk of serious damage to the hearing apparatus, mainly the tympanic membrane (TM) and middle ear (ME). We dissected and photodocumented the temporal bones of five newborn and three adult hooded seals in order to study the temporal bone structure and reveal its protective mechanisms for extreme pressure changes. Specimens were sectioned and stained for light microscopy. The thicknesses of the pars tensa and pars flaccida were found to average 60 and 180 microm, respectively. The ME cavity hosts a cavernous tissue of thin-walled vessels beneath the modified respiratory epithelium. The ME and external ear canal (EAC) volumes can be altered appreciably by filling/emptying the cavernous tissue with blood. The ossicles were fixed by contracting the tensor tympani and stapedius muscles simultaneously with complete occlusion of the EAC. According to Boyle's law, the volume of the gas-filled ME cavity at a depth of 1000 m is only 1% of its volume at the surface of the sea. Ascent from such a depth allows the gas in the ME cavity to expand, causing the TM to bulge laterally. This movement is counteracted by a reduction in the blood volume inside the cavernous sinuses, action in the tensor tympani and stapedius muscles and discharge of gas through the Eustachian tube. The presence of a firm, broad-based exostosis in the floor of the EAC lateral to the TM helps to obstruct the EAC.

Animals↗

Inflammatory chronic otitis media and the anterior epitympanic recess.

OBJECTIVE: To demonstrate the important role of the anterior epitympanic recess (AER) in the surgery of noncholesteatomateous chronic inflammatory middle ear disorders. To establish selective criteria as to the indication of surgical intervention on the AER, aiming to create a permanent anterior aeration pathway for the attic. In addition, to point out the mandatory role of preoperative temporal bone computed tomography (CT) demonstrating whether the AER is involved and thus contributing, within the clinical context, to the indication for this surgery and its appropriate approach. STUDY DESIGN: Prospective study on patients with persistent or recurring chronic inflammatory middle ear disease for at least 3 years, after failure of conventional medical or surgical treatments. SETTING: Tertiary referral university centre. PATIENTS: Between November 2002 and July 2003, every patient presenting with clinical findings suggestive of an AER pathology was included in this study. SURGERY: Surgical approach of the AER during a mastoatticotomy and tympanoplasty with excision of the Cog and the tensor tympani fold, preserving the ossicular chain in almost all cases. OUTCOME MEASURES: Absence of postoperative otorrhea, satisfactory otoscopic examination, and improvement in the air-bone gap postoperatively in case the presurgery hearing level was abnormal and not due to an ossicular chain abnormality. RESULTS: Eight patients were included in the study. The preoperative CT scan showed AER opacities in all patients that were either isolated or associated with a diseased meso- or hypotympanum or the mastoid cavity. The measurement of the relevant transverse diameter of the AER is proposed to evaluate preoperatively the distance between the Cog laterally and the facial nerve canal medially to minimize the risk of a perioperative injury. During the operation, we found granulation tissue and adhesions in the AER in all cases A clinical follow-up 3 months after the intervention showed good local control in all patients, absence of otorrhea, and almost complete closure of the air-bone gap at audiometric evaluation. The last clinical follow-up in August 2004, a mean of 18 months after our intervention, did not reveal any relapse of symptoms in any case. CT control could be obtained in five of eight cases, within 13 to 21 months after the intervention, showing a reaerated tympanic cavity and AER. CONCLUSION: The AER plays a major role in sustaining some noncholesteatomateous chronic or recurrent inflammatory middle ear disorders that do not respond to conventional medical treatment. Definitive control of this pathology will be obtained by approaching the AER through an excision of the Cog and the tensor tympani fold, exenterating the inflammatory tissues, and creating a sufficient and permanent anterior atticomesotympanic communication. The indication for such a surgical approach is highly dependent on clinical findings correlated to temporal bone CT. Familiarity with the AER and its critical role should become part of every resident's training program in otology.

Adolescent↗

Experimental observation of particulate flow along cranial nerves.

The purpose of this study was to investigate the communicative routes via the cranial nerves among the middle ear, the auditory tube, the inner ear, and the subarachnoid space under nearly physiological conditions. Various volumes of Indian ink were slowly injected into the facial nerve trunk of rabbits at the stylomastoid foramen, then serial sections of the heads were observed under the light microscope. This study yielded the following results: (i) Indian ink penetrated into the subarachnoid space through the internal auditory canal and/or the jugular foramen along the nerve sheaths of the VIIth, IXth, and/or Xth cranial nerves. (ii) Indian ink penetrated through the nerve sheaths of the cochlear, superior vestibular, and inferior vestibular nerves to the fundus of the internal auditory canal. (iii) Indian ink reached the scala tympani and the scala vestibuli via the cochlear aqueduct. (iv) Indian ink penetrated to the nerve sheaths of the tensor tympani and/or tensor palati nerves from the subarachnoid space of the trigeminal ganglion. In conclusion, it was shown that certain small particles are able to penetrate from the facial nerve sheath at the entrance of the stylomastoid foramen to the VIIIth, IXth, and Xth nerve trunks, the middle ear, the area around the auditory tube, the inner ear, and the subarachnoid space.

Animals↗

Epitympanic compartment surgical considerations: reevaluation.

The epitympanic compartments and the anatomy of the atticotympanic diaphragm were examined in a pair of serially sectioned temporal bones with secretory otitis media and chronic otitis media, respectively. Findings confirmed reports of 19th century scientists in that Prussak's space has a wide connection to the mesotympanum through the posterior pouch of Tröltsch and may have an additional narrow passage in its roof to the lateral malleal space. The lateral incudomalleal fold regularly separates the upper lateral attic from the lower lateral attic and the mesotympanum. The medial incudal fold as a rule is atrophic already at birth. The anterior tympanic isthmus thus extends from the tensor tympani tendon to the posterior incudal ligament and is the main passage for epitympanic and mastoid aeration. Opening(s) in the tensor fold, when present, are also important. In some ears, the posterior tympanic isthmus may form an auxiliary narrow route for aeration via the incudal fossa. The isthmi may be blocked by middle ear infection, which can lead to chronic mastoid and attic disease. Pathways for cholesteatoma spread in the epitympanum are discussed.

Cholesteatoma, Middle Ear↗

Controversy about the eustachian tube function.

The author suggests that the classic view on the function of the Eustachian tube remains controversial and should be reviewed: the gas exchange by vascular diffusion is apparently located in the antromastoid cavity where an overpressure occurs. This overpressure is equalized downwards to match the ambiant pressure, by the synergic activity of the tensor tympani and the fibro-cartilaginous Eustachian Tube.

Carbon Dioxide↗

Diagnosis of Menière's disease.

Stapedius-reflex measurement and the glycerol-test in combination with pure tone audiogram and speech-audiogram are reliable methods for an exact diagnosis of Menière's disease. For differential diagnosis one should know the so called "tensor tympani syndrome" which is discussed in this paper.

Audiometry↗

Are two muscles needed for the normal functioning of the mammalian middle ear?

Why do two muscles occur in the middle ear of most mammals? In this article selected explanations as to why two muscles occur are critically evaluated. It is argued that these explanations are not compelling. Data are then reviewed that indicate that the tensor tympani has no function to fulfil in the normal operation of the middle ear.

Animals↗

[Excision in the epipharynx anterior or posterior to the ostium tubae with stenosis of the cartilaginous eustachian tube (author's transl)].

A large excision anterior to the ostium tubae in the epipharynx is advised in cases with stenosis of the cartilagenes eustachian tube. The operations performed by transpalatimal approach under general anesthesia were in 11 cases without complications so far. Excision and scar retraction yielded good functioning results over the longest observation period of 18 month. -A resection of the tensor tympani muscle out of its bony canal is advised in bony tubal obstruction. Ventilation may be improved by use of our conic and oval shaped steel probe which helps to combine the bony tensor typani canal with the eustachian tube.

Constriction, Pathologic↗

Tympanic muscle reflex elicited by electric stimulation of the tongue in normal and pathological subjects.

A bilateral reflex contraction of the tensor tympani muscle has been obtained in man by electric stimulation of the tongue (1-2 mA). The stimulus is well tolerated and always effective. The advantage is stressed of eliciting a contraction of this muscle without involvement of the stapedius, as occurs with other methods. An analysis has been subsequently conducted in normal subjects and in patients affected by pathology of the tympano-ossicular system: tympanosclerosis, otosclerosis, suprastapedial facial paralysis; in cases of interruption of the afferent arch: section of the homo-lateral lingual nerve; in cases of involvement of its central portion: cerebello-pontine-angle tumours; and in cases of section of chorda tympani. A chiasm-like central nervous pattern is suggested.

Acoustic Stimulation↗

[Reaction of the tympanic tensor muscle--elicited by nasally applied trigeminal stimulants].

Computerised evaluation of tensor muscle reaction was carried out by using a biosignal analysing unit triggered by nasal inhalation. The trigeminus nerve was stimulated by application of 3-molar acetylacetic acid into the nasal respiratory air, inducing a contraction of the tympanic muscle, followed by a change in impedance. This change in impedance of the tympanic membrane ossicle system was recorded and printed out on a display. In this manner evidence was obtained of a tensor muscle reaction induced by the third branch of the trigeminal nerve as efference, and demonstrated for the first time. This reflex arc had long been considered as being of negligible clinical importance before its stimulation and measurement had become possible. It is a generally accepted theory that the reflex arc of the m. tensor tympani is linked to the formatio reticularis which assesses the sensory afferences. For this reason, the reflex arc habituates rapidly, and continuous stimulation is no longer possible.

Acetates↗

Sexual dimorphism of motorneurons: timbal muscle innervation in male periodical cicadas and homologous structures in females.

In 17-year cicadas, only the male has a sound-producing apparatus. It consists of paired abdominal timbals, each driven by a specialized timbal muscle. Each muscle is innervated by a large timbal motorneuron. Having the largest axon in the auditory nerve, its central structure is readily elucidated with cobalt. The largest cell in the female auditory nerve is found to be a motorneuron that bears striking resemblance to the timbal motorneuron of the male. On the basis of their anatomy within the CNS, we consider these cells to be homologous, despite the fact that the female has no apparent timbal muscle. Cobalt-filling to the periphery reveals the target muscle of the female motorneuron to be one of the three tensor tympani muscles supporting the tympanum; these muscles are not found in the male. The evolutionary significance of these findings is discussed in terms of a possible loss of the sound-producing apparatus in females.

Animals↗