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At least 19 recordsLinked to original sources
PubMed1979

[Physiopathology of the inner ear and therapy of presbyacusis (author's transl)].

Many experimental investigations have shown that labyrinthine fluids play a basic role in the physiology of the inner ear. Modifications of perilymphatic fluids have been demonstrated in perceptive deafness (otosclerosis, Ménière's disease, tympanolabyrinthosclerosis). Vasoactive agents fail to markedly affect the exchange between labyrinthine fluids, so that perceptive syndromes are generally regarded as unresponsive to treatment. Several studies have shown the effectiveness of 10-methoxy-1,6-diemthyl-ergoline-8 beta-methanol-(5-bromonicotinate) (nicergoline, Sermion) in various conditions of the inner ear. In this investigation, 30 patients with presbyacusis were treated with 30 mg/day p.o. for 30 days. Speech audiometric curves were improved in 4 out of 18 cases of physiological presbyacusis and in 6 out of 12 cases of accelerated presbyacusis. These results are very interesting, since few effective therapies are available to treat these conditions.

Animals↗
PubMedDate not supplied

Perilymph fistula: a cause of auditory, vestibular, neurological and psychiatric disorder.

It is suggested that damage by mild trauma, viruses or bone disease to the otic capsule or to the membranes between the cochlea and the middle ear is common, and involved in many syndromes of obscure etiology. The clinical perilymph fistula (PF) syndrome can consist of any combination of the following: tinnitus, deafness, phonophobia, vertigo, ataxia, otalgia, facial palsy, headache, diplopia, blackouts, psychological distress. The following testable hypotheses are proposed: otitis media is due to perilymph in the middle ear, with secondary changes resulting from infection or inflammation: otosclerosis results from a slow leak in the presence of enzymes promoting bone growth: Meniere's syndrome follows reduced perilymph support for the endolymphatic system: Bell's palsy results from a perilymph provoked oedema in the bony facial nerve canal: PFs may be responsible for progressive rubella deafness, and for some cases of migraine, epilepsy, anxiety neurosis and hysteria: psychiatric sequelae of the PF syndrome predominate in the post-concussional syndrome and infantile autism: organisms can pass from the throat into the spinal fluid, causing meningitis or encephalitis. The tinnitus and vertigo are caused by random labyrinthine fluid movements, the headache and diplopia by reduced spinal fluid pressure.

Deafness↗
PubMedDate not supplied

[Oscillometry on various stape protheses. Experimental examination of human temporal bone preparations].

In human temporal bone specimens the vibrations of the labyrinthine fluid were measured by a piezoelectric system after application of various techniques of otosclerosis surgery. Compared with the amplitude in the case of a normal stapes, the surgical techniques according to Zangemeister, Shea and Schuknect resulted in considerable transmission losses in the high frequency range, while transmission of low frequencies to the inner ear was almost equivalent to normal transmission via the stapes. For frequencies of more than 3,000 Hertz the damping influence of the fibrous tissue implanted into the oval window was verified. The results of surgery according to Zangemeister, Shea and Schuknechtdid not differ significantly in the low and medium frequency range. Only a Robinson prosthesis implanted like a Teflon piston caused an impairment of transmission, while the method of fitting this prosthesis onto fibrous tissue was equilvalent to the other techniques.

Ear, Middle↗
PubMed1992

The effect of posture on three objective audiological measures.

This study examines the effect of posture on click evoked otoacoustic emissions, tympanic membrane displacement, and travelling wave velocity obtained using the auditory brainstem response. Statistically significant changes with posture were observed for each technique. The changes in evoked emission and tympanic membrane displacement measurements were comparable with those reported by previous experiments. Travelling wave velocity measurements were shown to be sensitive to inferred posturally-induced changes in labyrinthine fluid pressure of around 150 mm saline. There was no statistically significant correlation between posturally-induced changes measured by the three techniques. It is suggested that different mechanisms are responsible for the posturally-induced changes observed for the three techniques.

Adult↗
PubMed1975

[Scanning electron microscopy of the vestibular surface of the stapes in otospongiosis].

The authors, going on with their investigations of the otospongiotic micro-foci by means of scanning electron microscopy method, state their discoveries concerning the micro-foci of the footplates vestibular side, left aside too often up to now. On this vestibular side of the footplate, they have managed to find much more numerous pathological alterations than usually admitted. There are three types of lesions: 1. Strongly cellular micro-foci, most of them composed of histiocytes. 2. Fibrous micro-foci, containing numerous fibroblasts and looking like otospongiotic micro-foci of osteoid lamellae overhanging the tympanic side of the footplate and grasping it in the way of a lobster-claw. 3. A small number of scattered microlesions, having no relation with the two previous types, and seeming due to numerous initial otospongiotic micro-foci originated from one or several cells with altered metabolism on the footplate' side itself. The localization of these micro-foci of the footplate's vestibular side is extremely interesting for the knowledge of the otospongiotic disease, because they are in direct contact with the vestibule. They can thus spread their hydrolytic enzymes into the labyrinthine fluids as well as the otospongiotic micro-foci of the lateral wall which have been described by the authors in numerous papers.

Ear Ossicles↗
PubMed1979

Effect of urea on osmolality of perilymph.

Blood osmolality was altered in chinchillas by intravenous administration of urea. Serum osmolality peaked rapidly at 30 minutes after administration and decreased slightly to a plateau for 180 minutes. Perilymph and CSF osmolality lagged substantially behind the increase in serum osmolality and equaled serum osmolality only after one hour. Perilymph osmolality followed changes in the serum up to 60 minutes with a definite time lag. This phenomenon suggests the existence of a selective blood-labyrinth barrier that is permeable to urea and water. However, the time lag due to the barrier may permit the reduction of hydrostatic pressure in the labyrinth. The results of the present study seem to render partial explanation of improved hearing in patients with Meniere's disease who were treated with urea.

Animals↗
PubMed1976

Osmolality changes in perilymph after systemic administration of glycerin.

Blood osmolality was altered in guinea pigs by intravenous administration of glycerin (glycerol). After glycerin administration, serum osmolality increased rapidly, reaching a plateau within 15 minutes. Perilymph osmolality lagged significantly behind the increase of serum osmolality and equalled serum osmolality only after one hour. While perilymph osmolality responded to changes of serum osmolality, there was some time lag noted in the response of perilymph, suggesting the existence of a blood-labyrinth barrier. It was observed that this barrier is permeably to glycerin and water, suggesting the possibility of transient reduction of hydrostatic pressure in the labyrinth by the injection of an osmotic agent into the systemic circulation.

Animals↗
PubMed1976

[Otitis media and cochlea. Morphological and biochemical studies in guinea pigs (author's transl)].

The paper deals with: 1. the protein concentration in the perilymph (PL), the serum and the cerebrospinal fluid (CSF), 2. the protein pattern in the PL and 3. histological findings in the middle and inner ear in unilaterally ear-infected guinea pigs. The studies were performed 6 h to 21 days post infectionem (Fig. 1). The pathological changes in the middle ear, which, in most cases, were limited to the infected ear, were initially evaluated under the operating microscope and divided into 4 stages. The analytical and histological results were presented as functions of these stages. As the inflammation intensity increased, the protein concentration in the PL of the infected ears increased to a level exceeding that of the normal value more than ten times (Fig. 2). However, in the serum and in the CSF this concentration remained unchanged. Likewise, no significant protein increase in the PL of the contralateral ears was detectable in most cases. As the inflammation intensity increased, the number of the precipitation lines detectable immunoelectrophoretically increased in the PL of the infected ears (Fig. 3). An increase in the alpha1- and gamma-globulins and a decrease in Albumin was found by electrophoresis on cellulose acetate strips (Tab. 3). The histological findings correlated with initially established inflammatory stages of the middle ear mucous membrane (Tab. 4). As the inflammation intensity increased, the round window, too, was changed pathologically, so that in some cases of purulent otitis media middle ear secretion could enter the cochlea. The protein increase in the PL immediately after the infection is probably due to an increase in the blood vessel permeability in the inner ear.

Animals↗
PubMed1978

Chemical composition in various compartments of inner ear fluid.

Sodium, potassium, chloride, glucose and total protein were determined in samples of scala vestibuli perilymph, scala tympani perilymph, CSF, cochlear endolymph and utricular endolymph from normal cats. Small but significant differences were evident in the concentrations of sodium and potassium between the scala vestibuli and scala tympani perilymph. It was also apparent that each compartment of endolymph has different values for sodium and potassium concentrations. Compared with the endolymph, the perilymph was found to contain a higher concentration of glucose and total protein. These findings are discussed from the view point of biological significance.

Cerebrospinal Fluid↗
PubMed1977

Labyrinth and cerebral-spinal fluid pressure changes in guinea pigs and monkeys during simulated zero G.

This study was undertaken to explore the hypothesis that shifts of body fluids from the legs and torso toward the head contribute to the motion sickness experienced by astronauts and cosmonauts. The shifts in body fluids observed during zero-G exposure were simulated by elevating guinea pigs' and monkeys' torsos and hindquarters. Cerebral-spinal fluid pressure was recorded from a transducer located in a brain ventricle; labyrinth fluid pressure was recorded from a pipette cemented in a hole in a semicircular canal. An anticipated divergence in cerebral-spinal fluid pressure and labyrinth fluid pressure during torso elevation was not observed. The results of this study do not support a fluid shift mechanism of zero-G-induced motion sickness. However, a more complete test of the fluid shift mechanism would be obtained if endolymph and perilymph pressure changes were determined separately; we have been unable to perform this test to date.

Animals↗
PubMed1977

[Determination of the perilymph density in the cochlea of guinea pigs (author's transl)].

The perilymph density of the sc. tympani, sc. vestibuli and the density of liquor cerebrospinalis in guinea-pigs are measured by determination from mass and volume of the fluid column in a glass capillary tube. For the density of perilymph in sc. vest. a value of (formula: see text) in sc. tymp. a value of (formula: see text), and for liquor a value of (formula: see text) was obtained.

Animals↗
PubMed1976

Quantitative assessment of perilymph sources.

The problem of the perilymph origin--influx of cerebrospinal fluid (CSF) versus ultrafiltration within the cochlea--cannot be solved by mere qualitative proofs of tracer passage through the cochlear aqueduct. In order to gain quantitative data on the possible perilymph sources, an experimental study was designed to follow the time course of dye concentrations in the cisternal CSF and in the perilymph after tracer injection into the CSF at the vertex. By comparing the resulting concentration peaks in both fluids, the mean peak of the perilymph tracer concentrations was found to reach 36% of the maximum CSF concentration only. It is concluded that the local perilymph production within the cochlea exceeds the influx of CSF by a ratio of about 2:1. A working hypothesis of the double perilymph origin is discussed.

Animals↗
PubMedDate not supplied

[Protein study on perilymph susbstitution during cerebrospinal fluid flow through cochlear aqueduct].

Total protein contents in the perilymphy of Scala vestibuli and Scala tympani as well as in the cerobrospinal fluid (CSF) of guinea-pigs were determined, by which specimens were taken under the following various conditions: With or without subarachnoidal puncture before perilymph collection, by varying the amount of perilymph taken from Scala tympani, by fractionating collection and under post mortem condition. The results suggest that under physiological conditions the CSF also flows through the cochleae aqueduct and the protein concentration in the Scala tympani decreases especially in the basal winding. Because the protein content in CSF is inaverage four times lower than in fluids of the inner ear it is of preference to consider the question of connection between the CSF and the fluids of the inner ear. In the specimens taken the blood contamination was estimated on the basisof erythrocytes in the connection capillaries under microscope. The protein content in the perilymph of Scala vestibuli was found significantly higher in relation to perilymph of Scala tympani.

Animals↗