Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Perilymph”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

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

At least 289 records · Page 16Linked to original sources
PubMed1988

[Oxygen partial pressure measurements in the perilymph and scala tympani in normo- and hyperbaric conditions. An animal experiment study].

The purpose of this study was to examine the influence of hyperbaric oxygen on the oxygen tension (pO2) in the normal inner ear. We examined 16 anaesthetised guinea pigs by means of an oxygen-sensitive micro-coaxial needle electrode, using the method described by Baumgaertl and Luebbers. In all animals the pO2 in the perilymph of the scala tympani fell by 34% of the original value during insertion of the sensor into the scala tympani. After we had flooded the hyperbaric chamber with pure oxygen under normobaric conditions the pO2 increased by 244.3% of the original values. Furthermore the pO2 increased by 9.4 times the original values during hyperbaric oxygen at 1.6 bar.

Animals↗
PubMed1987

Persistent traumatic perilymph fistulas.

Thirty-four ears have been explored to rule out perilymph fistulas resulting from ear trauma. Eight ears (24%) were identified with a fistula, often persisting months (average 7.5 months) after the precipitating injury. Repair of fistulas, even if done relatively late, markedly reduces vestibular symptoms and may improve low and middle frequency sensorineural hearing. Complications from negative explorations are rare.

Ear↗
PubMed1987

Perilymph fistula: an important cause of deafness and dizziness in children.

This study underscores the importance of considering a perilymph fistula, an abnormal communication between the inner and middle ear, in any child with a progressive sensorineural hearing loss. A concomitant complaint of intermittent dizziness or observed spells of imbalance (56%) is another indication of the disease. Six of 16 patients (37.5%) with proven fistulas were less than 2 years of age at the onset of symptoms. Unless the fistula is identified and repaired by grafting, the ear may become totally deaf. This would be disastrous in the presence of bilateral fistulas, which occur commonly in children (56% of patients had symptoms of bilateral disease). Our experience in recognizing and treating fistulas and thereby saving and restoring hearing is described.

Adolescent↗
PubMed2005

Persistence of perilymph fistula mechanism in a completely paretic posterior semicircular canal.

The three dimensional eye movements (search coil technique) of a patient with a completely paretic left posterior semicircular canal as a result of a perilymph fistula (PLF) were studied. The patient still exhibited pressure induced nystagmus that obeyed Ewald's first law. This finding cannot be explained by otolith stimulation, but might indicate that PLF mechanisms either persist in canal plugging or act on the ampulla by directly deflecting the cupula.

Adult↗
PubMed1994

Loss of perilymph affects electrocochleographic potentials in the guinea pig.

Alterations of electrocochleographic (ECoG) potentials recorded from guinea pig cochleae have been reported to occur following round window (RW) membrane perforation (perilymphatic fistula). To further evaluate the pathophysiology of perilymphatic fistula, a study was conducted of the short-term effects of acute RW membrane perforation on the amplitude of the summating potential (SP) and the action potential (AP), and the SP:AP ratio. Acute RW membrane perforation was produced in 15 Hartley guinea pigs. The animals were placed in a head dependent position, so that some perilymph would drain from the inner ear following RW perforation. For both click and low frequency tone burst stimuli (2 kHz), the mean AP amplitudes showed variable but progressive deterioration with time following RW membrane perforation. Action potential latencies showed a significant increase with time for both click and tone burst stimuli. Summating potential amplitudes for click and tone burst were typically stable or slightly decreased. Interanimal variability of all measures was typically high. However, AP and SP amplitudes in the same animal were consistently and differentially affected by perforation of the RW membrane. There also were differential effects on the positive and the negative components of the SP, suggesting the interplay of several generator mechanisms. The authors conclude that AP amplitude and, consequently, the SP:AP ratio are sensitive to the creation of a perilymphatic fistula. These results provide support for the use of ECoG tests in the diagnosis of perilymphatic fistula.

Animals↗
PubMed1985

Freeze-fracture studies on the perilymph-endolymph barrier in experimentally induced hydrops.

A double-blind study was performed on nine pigmented guinea pigs which were unilaterally operated on in order to create an endolymphatic hydrops. After 12-18 months, both inner ears of the animals were removed and investigated by the freeze-fracture technique. The ultrastructure of the epithelial cells lining the endolymphatic compartment of the cochlea and the vestibular apparatus was analyzed. Special attention was directed to possible changes of the tight junctions (zonulae occludentes) in these sites. The number and depth of strands between the cells of sensory and non-sensory epithelia of both operated and unoperated sides were compared by an examiner unaware of the operated side. After the code of double-blind study was broken, it was found that there were no significant differences between the operated and the unoperated ears. These results are discussed in relation to the late DC-potential decrease in experimentally induced hydrops.

Animals↗
PubMed1975

[Kinetics of resorption in the cochlear perilymph after charging with radionuclides (author's transl)].

The perilymphatic space of the guinea pig's cochlea is filled within 1 to 3 min with an isotonic Ringer solution labelled with a radionuclide. The cochlea is neatly sealed immediately afterwards, thus causing only a minimal disturbance in the inner ear. The animal's cochlea is brought into the strict focus of a small detector as quickly as possible, the decay of activity is continuously controlled for 2 to 10 hrs. The radionuclides used are Cl36, Na22, and Tc99m. The decay of activity of the cochlea is strongly believed to accord to a simple exponential law; half lives range from about one to about three hours. Cl36 and Tc99m were used for the first time in studying cochlear kinetics.

Animals↗