Imaging of Auditory Brain Stem Implants

Neurographics ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 202-210
Author(s):  
K.F. Summers ◽  
N.R. Harn ◽  
L.N. Ledbetter ◽  
J.D. Leever ◽  
J.R. Bertsch
Keyword(s):  
Postoperative Complications ◽  
Brain Stem ◽  
Imaging Appearance ◽  
Auditory Rehabilitation ◽  
Implant Placement ◽  
Cochlear Nuclei ◽  
Auditory Brain Stem ◽  
Safety Considerations ◽  
Neuroprosthetic Devices ◽  
Lead Positioning

Auditory brain stem implants are infrequently encountered neuroprosthetic devices used for auditory rehabilitation in deaf patients with pathology between the cochlea and cochlear nuclei who would not benefit from cochlear implantation. This article reviews the device, the relevant anatomy, audiologic performance, operative approaches, and conditions in which auditory brain stem implants are indicated. The imaging appearance of auditory brain stem implants, including optimal lead positioning, and imaging safety considerations of the device are also discussed. Knowledge of the device can assist the radiologist in detecting postoperative complications and component malpositioning and in providing safe and effective imaging practices in patients with indwelling auditory brain stem implants.Learning Objective: To describe the auditory brain stem implant device, identify optimal lead positioning, and list indications for auditory brain stem implant placement.

Synaptic Physiology in the Cochlear Nucleus Angularis of the Chick

2005 ◽  
Vol 93 (5) ◽  
pp. 2520-2529 ◽  
Author(s):  
Katrina M. MacLeod ◽  
Catherine E. Carr
Keyword(s):  
Brain Stem ◽  
Time Constant ◽  
Auditory Nerve ◽  
Sound Intensity ◽  
Sound Recognition ◽  
Auditory Information ◽  
Decay Kinetics ◽  
Cochlear Nuclei ◽  
Auditory Brain Stem ◽  
Nucleus Angularis

Nucleus angularis (NA), one of the two cochlear nuclei in birds, is important for processing sound intensity for localization and most likely has role in sound recognition and other auditory tasks. Because the synaptic properties of auditory nerve inputs to the cochlear nuclei are fundamental to the transformation of auditory information, we studied the properties of these synapses onto NA neurons using whole cell patch-clamp recordings from auditory brain stem slices from embryonic chickens (E16–E20). We measured spontaneous excitatory postsynaptic currents (EPSCs), and evoked EPSCs and excitatory postsynaptic potentials (EPSPs) by using extracellular stimulation of the auditory nerve. These excitatory EPSCs were mediated by AMPA and N-methyl-d-aspartate (NMDA) receptors. The spontaneous EPSCs mediated by AMPA receptors had submillisecond decay kinetics (556 μs at E19), comparable with those of other auditory brain stem areas. The spontaneous EPSCs increased in amplitude and became faster with developmental age. Evoked EPSC and EPSP amplitudes were graded with stimulus intensity. The average amplitude of the EPSC evoked by minimal stimulation was twice as large as the average spontaneous EPSC amplitude (∼110 vs. ∼55 pA), suggesting that single fibers make multiple contacts onto each postsynaptic NA neuron. Because of their small size, minimal EPSPs were subthreshold, and we estimate at least three to five inputs were required to reach threshold. In contrast to the fast EPSCs, EPSPs in NA had a decay time constant of ∼12.5 ms, which was heavily influenced by the membrane time constant. Thus NA neurons spatially and temporally integrate auditory information arriving from multiple auditory nerve afferents.

Experimental Study following Inactive Implantation of an Auditory Brain Stem Implant in Nonhuman Primates

2000 ◽  
Vol 109 (2) ◽  
pp. 163-169 ◽  
Author(s):  
Manuel Manrique ◽  
Isabel Jauregui ◽  
Ana Insausti ◽  
Ricardo Insausti ◽  
Francisco J. Cervera-Paz ◽  
...  
Keyword(s):  
Brain Stem ◽  
Nonhuman Primates ◽  
Adverse Reactions ◽  
Giant Cells ◽  
Surgical Trauma ◽  
Back Side ◽  
Platinum Electrodes ◽  
Cochlear Nuclei ◽  
Auditory Brain Stem ◽  
Histologic Changes

We report changes in the cochlear nuclei (CNs) after 3 months of bilateral auditory deafferentation and simultaneous unilateral implantation of a dummy auditory brain stem implant (ABI) in 6 nonhuman primates ( Macaca fascicularis). These specimens were compared to CNs of 9 controls and 7 bilaterally deafferented animals without implantation. The ABI array consists of 3 platinum electrodes mounted on a silicone pad with the back side covered with Dacron. No migration of the ABI was observed. All deafferented animals showed astrocytic reorganization in the CNs. Histologic changes consisted of superficial reactions around the implant, with formation of fibrillar bundles of fusiform cells, and the presence of giant cells close to the Dacron. Other findings were related to surgical trauma. The dummy ABI did not itself provoke serious adverse reactions in the CNs. Our observations support the possibility of ABI reimplantation surgery.

A Model for Auditory Brain Stem Implants: Bilateral Surgical Deafferentation of the Cochlear Nuclei in the Macaque Monkey

2007 ◽  
Vol 28 (3) ◽  
pp. 424-433 ◽  
Author(s):  
Francisco Javier Cervera-Paz ◽  
Enrique Salda??a ◽  
Manuel Manrique
Keyword(s):  
Brain Stem ◽  
Macaque Monkey ◽  
Cochlear Nuclei ◽  
Auditory Brain Stem

scholarly journals Can auditory brain stem response accurately reflect the cochlear function?

2020 ◽  
Vol 124 (6) ◽  
pp. 1667-1675
Author(s):  
Dalian Ding ◽  
Jianhui Zhang ◽  
Wenjuan Li ◽  
Dong Li ◽  
Jintao Yu ◽  
...  
Keyword(s):  
Brain Stem ◽  
Damage Model ◽  
Compound Action Potential ◽  
Cochlear Function ◽  
Auditory Brain Stem Response ◽  
Threshold Difference ◽  
Auditory Brain Stem ◽  
Cochlear Damage ◽  
Brain Stem Response ◽  
Compound Action

Auditory brain stem response (ABR) is more commonly used to evaluate cochlear lesions than cochlear compound action potential (CAP). In a noise-induced cochlear damage model, we found that the reduced CAP and enhanced ABR caused the threshold difference. In a unilateral cochlear destruction model, a shadow curve of the ABR from the contralateral healthy ear masked the hearing loss in the destroyed ear.

Auditory brain-stem responses (ABRs) in sleep respiratory disorders

1994 ◽  
Vol 24 (3) ◽  
pp. 156-160 ◽  
Author(s):  
J. PAQUEREAU ◽  
J. C. MEURICE ◽  
J. P. NEAU ◽  
P. INGRAND ◽  
F. PATTE
Keyword(s):  
Brain Stem ◽  
Respiratory Disorders ◽  
Auditory Brain Stem Responses ◽  
Auditory Brain Stem

Auditory brain stem responses (ABR) in developmentally retarded infants and children

1986 ◽  
Vol 8 (3) ◽  
pp. 246-256 ◽  
Author(s):  
Yasuhiro Mochizuki ◽  
Hideo Ohkubo ◽  
Akira Yoshida ◽  
Takako Tatara
Keyword(s):  
Brain Stem ◽  
Infants And Children ◽  
Auditory Brain Stem Responses ◽  
Auditory Brain Stem
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