Search results for "Round window"
showing 8 items of 8 documents
Elektrophysiologische Untersuchung zum Einsatz von Streptolysin O und Natrium-Hyaluronat zur Permeabilitätsmodulation der Membran des runden Fensters…
2003
Background: The round window membrane (RWM) acts like a barrier for topically applied substances into the middle ear preventing diffusion into the perilymphatic fluid compartment. Material and Method: In an animal model, modulation of the permeability of the RWM was attempted using Streptolysin-O (SLO) in various concentrations and sodium hyaluronate. Thereafter, the effect of intratympanically applied Lidocain 2% on hearing threshold measured by auditory brainstem response was tested for Lidocain 2 % and Lidocain 2 % in combination with SLO or sodium hyaluronate. Results: The results show that both, SLO and sodium hyaluronate, influence the effect of Lidocain 2 % on hearing thresholds as a…
Treatment of sudden sensorineural hearing loss with transtympanic injection of steroids as single therapy: a randomized clinical study.
2011
The aim of this study was to verify the efficacy and the safety of transtympanic dexamethasone to treat sudden sensorineural hearing loss as first and single drug method. Considering ethical implication of performing a mininvasive procedure on middle ear, we matched such proposed treatment with systemic prednisone administration that represents the widest adopted protocol. Randomized prospective study was conducted. The inclusion criterion was a sudden sensorineural hearing loss of at least 30 dB across three contiguous frequencies over a period of 24 h. Group A received transtympanic steroid injections; Group B received oral administration of steroids. 25 patients were treated with transty…
Intratympanic Dexamethasone and Hyaluronic Acid in Patients with Low-Frequency and Ménière's-Associated Sudden Sensorineural Hearing Loss
2005
Steroids are widely used for the treatment of cochleovestibular disorders. Direct steroid application in the middle ear cavity, when combined with a round window membrane permeability-modulating substance, increases the level of the steroid reaching the target cells. We measured hearing in patients with idiopathic isolated low-frequency sensorineural hearing loss and in patients with sudden sensorineural hearing loss and a history of Ménière's disease. Contradictory reports about effectiveness of intratympanic steroid therapy on vertigo control and hearing improvement in patients with Ménière's disease exist in the literature.Eighteen patients with isolated low-frequency idiopathic sudden s…
[Treatment of sensorineural hearing loss in acute viral otitis media with intratympanic dexamethasone and hyaluronic acid in comparison with intraven…
2006
Background: Intratympanic dexamethasone with hyaluronic acid has shown to be an effective treatment of the inner ear damage in sudden hearing loss and Meniere's disease. It is not known yet if the same applies to the toxic inner ear damage in acute viral otitis media. Patients: Retrospectively, 26 patients who suffered from acute viral otitis media with sensorineural hearing loss were examined with regard to the improvement of their inner ear hearing loss. Twelve patients were treated with intravenous therapy only, consisting of hydroxyethylstarch, pentoxifylline and prednisolone. Fourteen patients additionally received intratympanic injections, consisting of dexamethasone and hyaluronic ac…
The role of fissula ante fenestram in unilateral sudden hearing loss
2016
The cause of unilateral sudden sensorineural hearing loss (SNHL) remains unclear in many clinical cases. Perilymphatic leakage through a fissula ante fenestram (FAF) fistula is one possible reason. We present four clinical cases with proven FAF fistula, discovered during surgical exploration. All patients experienced partial hearing recovery after surgical coverage of the fistula. We suggest FAF as a possible site for perilymphatic leakage, representing an anatomical correlate for sudden unilateral SNHL. We recommend early exploratory tympanotomy with special attention to the bony region, anterior to the oval window, in cases of severe sudden SNHL and suspected FAF.
Open-Loop Drug Delivery Strategy to the Cochlea using a Permanent Magnetic Actuator
2018
International audience; The use of robotic devices for drug delivery in sensitive area of the human body is an innovative and reliable solution. Most of them use magnetics fields, to steer micro-nanorobots into diseases locations. In this study, we use a magnetic actuator based on two permanent magnets as an end-effector of a robotic manipulator. The actuator offers the possibility to generate both pushing and pulling forces on the magnetic actuator axis in an open-loop control way. We describe in this paper the robotic drug delivery strategy that we implemented in a 6 degree of freedom robotic manipulator to push and to steer a magnetic microparticle from the round window to the apex of th…
Anatomy of cochlea and round window
2010
One of the most important functions of the ear is sound recepction, particularly the detection of amplitude and frequency of the sound waves by Corti's organ. The latter is a sensory structure located in the cochlear duct (middle scale), consisting of hair cells lying above the basilar membrane. The cochlear duct is surrounded by two cavities containing perilymph: the scala vestibularis and the scala tympani. The sound reception mechanism involves several other components of the ear such as malleus, incus and stapes, in the tympanic cavity, and the oval and round windows. The movement of the stapes on the oval window, that is adjacent to the scala vestibularis, generates pressure waves in t…
Bacterial Cytolysin Perturbs Round Window Membrane Permeability Barrier In Vivo: Possible Cause of Sensorineural Hearing Loss in Acute Otitis Media
1998
ABSTRACT The passage of radioiodinated streptolysin-O (SLO) and albumin through the round window membrane (RWM) was studied in vivo. When applied to the middle ear, SLO became quantitatively entrapped in this compartment and no passage to the cochlea occurred. However, flux of radioiodinated albumin through the toxin-damaged RWM was observed. We propose that the passage of noxious macromolecules, such as proteases, from a purulent middle-ear effusion may be facilitated by pore-forming toxins, resulting in cochlear damage and sensorineural hearing loss.