OBJECTIVE: : The pathophysiologic mechanisms resulting in hearing loss during electrode implantation are largely unknown. To better understand the functional implications of electrode implantation, we recorded the effects of cochlear damage on acoustically evoked intracochlear measurements using normal-hearing gerbils. METHODS: : A metal electrode was placed on the surface of the round window, and recordings of the cochlear microphonic (CM) and compound action potential (CAP) were made in response to stimulation with tone-bursts at various frequencies in 1-octave intervals and at intensities of 15 to 72 dB sound pressure level. The electrode was then advanced incrementally, with CM and CAP measurements obtained at each step. These data were compared with data obtained at the round window, and the electrode was withdrawn when a significant change was observed. After electrophysiological analysis, the cochlea was examined histologically. RESULTS: : Results show that on electrode insertion, loss of amplitude in the CM and CAP occurs after damage to cochlear structures. Loss of activity was typically first apparent in the CAP rather than the CM. CONCLUSION: : These results suggest that a reduction of the CAP can be an early marker of interaction of the electrode with cochlear structures. Such measurements are potentially available with slight modifications to current cochlear implant technology.
OBJECTIVE: : The pathophysiologic mechanisms resulting in hearing loss during electrode implantation are largely unknown. To better understand the functional implications of electrode implantation, we recorded the effects of cochlear damage on acoustically evoked intracochlear measurements using normal-hearing gerbils. METHODS: : A metal electrode was placed on the surface of the round window, and recordings of the cochlear microphonic (CM) and compound action potential (CAP) were made in response to stimulation with tone-bursts at various frequencies in 1-octave intervals and at intensities of 15 to 72 dB sound pressure level. The electrode was then advanced incrementally, with CM and CAP measurements obtained at each step. These data were compared with data obtained at the round window, and the electrode was withdrawn when a significant change was observed. After electrophysiological analysis, the cochlea was examined histologically. RESULTS: : Results show that on electrode insertion, loss of amplitude in the CM and CAP occurs after damage to cochlear structures. Loss of activity was typically first apparent in the CAP rather than the CM. CONCLUSION: : These results suggest that a reduction of the CAP can be an early marker of interaction of the electrode with cochlear structures. Such measurements are potentially available with slight modifications to current cochlear implant technology.
Authors: Robert J S Briggs; Michael Tykocinski; Jin Xu; Frank Risi; Martin Svehla; Robert Cowan; T Stover; P Erfurt; Thomas Lenarz Journal: Audiol Neurootol Date: 2006-10-06 Impact factor: 1.854
Authors: Chris James; Klaus Albegger; Rolf Battmer; Sandro Burdo; Naima Deggouj; Olivier Deguine; Norbert Dillier; Michel Gersdorff; Roland Laszig; Thomas Lenarz; Manuel Manrique Rodriguez; Michel Mondain; Erwin Offeciers; Angel Ramos Macías; Richard Ramsden; Olivier Sterkers; Ernst Von Wallenberg; Benno Weber; Bernard Fraysse Journal: Acta Otolaryngol Date: 2005-05 Impact factor: 1.494
Authors: Oliver Adunka; Wolfgang Gstoettner; Markus Hambek; Marc H Unkelbach; Andreas Radeloff; Jan Kiefer Journal: ORL J Otorhinolaryngol Relat Spec Date: 2004 Impact factor: 1.538
Authors: Adrien A Eshraghi; Marek Polak; Jiao He; Fred F Telischi; Thomas J Balkany; Thomas R Van De Water Journal: Otol Neurotol Date: 2005-05 Impact factor: 2.311
Authors: Andrew K Pappa; Kendall A Hutson; William C Scott; J David Wilson; Kevin E Fox; Maheer M Masood; Christopher K Giardina; Stephen H Pulver; Gilberto D Grana; Charles Askew; Douglas C Fitzpatrick Journal: J Neurophysiol Date: 2019-04-03 Impact factor: 2.714
Authors: Christine DeMason; Baishakhi Choudhury; Faisal Ahmad; Douglas C Fitzpatrick; Jacob Wang; Craig A Buchman; Oliver F Adunka Journal: Ear Hear Date: 2012 Jul-Aug Impact factor: 3.570
Authors: Adam P Campbell; Thomas A Suberman; Craig A Buchman; Douglas C Fitzpatrick; Oliver F Adunka Journal: Laryngoscope Date: 2010-08 Impact factor: 3.325
Authors: Adam P Campbell; Thomas A Suberman; Craig A Buchman; Douglas C Fitzpatrick; Oliver F Adunka Journal: Otol Neurotol Date: 2010-12 Impact factor: 2.311
Authors: Thomas A Suberman; Adam P Campbell; Oliver F Adunka; Craig A Buchman; Joseph P Roche; Douglas C Fitzpatrick Journal: Otol Neurotol Date: 2011-06 Impact factor: 2.311
Authors: Faisal I Ahmad; Baishakhi Choudhury; Christine E De Mason; Oliver F Adunka; Charles C Finley; Douglas C Fitzpatrick Journal: Laryngoscope Date: 2012-01-17 Impact factor: 3.325
Authors: Christopher K Giardina; Tatyana E Khan; Stephen H Pulver; Oliver F Adunka; Craig A Buchman; Kevin D Brown; Harold C Pillsbury; Douglas C Fitzpatrick Journal: Ear Hear Date: 2018 Nov/Dec Impact factor: 3.570
Authors: Oliver F Adunka; Christopher K Giardina; Eric J Formeister; Baishakhi Choudhury; Craig A Buchman; Douglas C Fitzpatrick Journal: Laryngoscope Date: 2015-09-11 Impact factor: 3.325
Authors: Baishakhi Choudhury; Oliver Franz Adunka; Omar Awan; John Maxwell Pike; Craig A Buchman; Douglas C Fitzpatrick Journal: Otol Neurotol Date: 2014-03 Impact factor: 2.311
Authors: Christopher K Giardina; Kevin D Brown; Oliver F Adunka; Craig A Buchman; Kendall A Hutson; Harold C Pillsbury; Douglas C Fitzpatrick Journal: Ear Hear Date: 2019 Jul/Aug Impact factor: 3.570