Dynamics of inner ear pressure release, measured with a double-barreled micropipette in the guinea pig

Wit, H. P.; Thalen, Elisabeth; Albers, F. W. J.

doi:10.1016/s0378-5955(99)00048-9

Cited by 28 publications

(23 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The discharge capillary was connected to a static pressure head of 20 cm of water and the steady state motion of displacement of a meniscus was monitored and found to be unchanged. Static pressure in the perilymphatic compartment of the guinea pig is around 2.6 cm of water [15]. …”

Section: Resultsmentioning

confidence: 99%

Development of a Microfluidics-Based Intracochlear Drug Delivery Device

et al. 2009

View full text Add to dashboard Cite

Background: Direct delivery of drugs and other agents into the inner ear will be important for many emerging therapies, including the treatment of degenerative disorders and guiding regeneration. Methods: We have taken a microfluidics/MEMS (MicroElectroMechanical Systems) technology approach to develop a fully implantable reciprocating inner-ear drug-delivery system capable of timed and sequenced delivery of agents directly into perilymph of the cochlea. Iterations of the device were tested in guinea pigs to determine the flow characteristics required for safe and effective delivery. For these tests, we used the glutamate receptor blocker DNQX, which alters auditory nerve responses but not cochlear distortion product otoacoustic emissions. Results: We have demonstrated safe and effective delivery of agents into the scala tympani. Equilibration of the drug in the basal turn occurs rapidly (within tens of minutes) and is dependent on reciprocating flow parameters. Conclusion: We have described a prototype system for the direct delivery of drugs to the inner ear that has the potential to be a fully implantable means for safe and effective treatment of hearing loss and other diseases.

show abstract

Section: Resultsmentioning

confidence: 99%

Development of a Microfluidics-Based Intracochlear Drug Delivery Device

et al. 2009

View full text Add to dashboard Cite

show abstract

“…The model incorporates fluid viscosity into the damping of the TM and BM. stiffness of the round window, we use 1.8 Â 10 3 N/m 3 (4 orders less than the value in Wit et al 27 ), which is essentially a pressure release condition. 29 the MET sensitivity is a parameter which is adjusted according to the model predictions' match to experimental data.…”

Section: Model Descriptionmentioning

confidence: 99%

Direction of wave propagation in the cochlea for internally excited basilar membrane

Grosh

2012

The Journal of the Acoustical Society of America

View full text Add to dashboard Cite

Otoacoustic emissions are an indicator of a normally functioning cochlea and as such are a useful tool for non-invasive diagnosis as well as for understanding cochlear function. While these emitted waves are hypothesized to arise from active processes and exit through the cochlear fluids, neither the precise mechanism by which these emissions are generated nor the transmission pathway is completely known. With regard to the acoustic pathway, two competing hypotheses exist to explain the dominant mode of emission. One hypothesis, the backward-traveling wave hypothesis, posits that the emitted wave propagates as a coupled fluid-structure wave while the alternate hypothesis implicates a fast, compressional wave in the fluid as the main mechanism of energy transfer. In this paper, we study the acoustic pathway for transmission of energy from the inside of the cochlea to the outside through a physiologically-based theoretical model. Using a well-defined, compact source of internal excitation, we predict that the emission is dominated by a backward traveling fluid-structure wave. However, in an active model of the cochlea, a forward traveling wave basal to the location of the force is possible in a limited region around the best place. Finally, the model does predict the dominance of compressional waves under a different excitation, such as an apical excitation.

show abstract

“…Fits to the inner ear pressure equalization curves after a sudden intracranial or EEC pressure change were made with different functions [20]: 1. A Single Exponential Function.…”

Section: Handling Of Datamentioning

confidence: 99%

Inner ear pressure changes following square wave intracranial or ear canal pressure manipulation in the same guinea pig

Thalen¹,

Wit²,

Segenhout³

et al. 2002

European Archives of Oto-Rhino-Laryngology

View full text Add to dashboard Cite

Inner ear pressure was measured in scala tympani with a micropipette during square wave pressure manipulation of the intracranial compartment and, subsequently, of the external ear canal (EEC) in the same guinea pig. As expected, the combination of the cochlear aqueduct and the inner ear behaves as a low-pass filtering system for intracranial pressure manipulation and as a complementary high-pass system for ear canal pressure manipulation. Time constants for pressure equalization were in the order of seconds and depended on the direction of flow through the cochlear aqueduct. Pressure equalization curves could not be fitted to a single exponential function; more complicated functions were needed for good fits, showing that the pressure equalization process is nonlinear. This means that the flow resistance of the cochlear aqueduct and/or the compliance of the cochlear windows is not constant, which is in accordance with a flow-direction dependent resistance of the cochlear aqueduct. An explanation for this can be found in the special structure of the periotic duct inside the aqueduct.

show abstract

Dynamics of inner ear pressure release, measured with a double-barreled micropipette in the guinea pig

Cited by 28 publications

References 27 publications

Development of a Microfluidics-Based Intracochlear Drug Delivery Device

Development of a Microfluidics-Based Intracochlear Drug Delivery Device

Direction of wave propagation in the cochlea for internally excited basilar membrane

Inner ear pressure changes following square wave intracranial or ear canal pressure manipulation in the same guinea pig

Contact Info

Product

Resources

About