Factors Predicting Postoperative Sentence Scores in Postlinguistically Deaf Adult Cochlear Implant Patients

A sample of 64 postlinguistically profoundly to totally deaf adult cochlear implant patients were tested without lipreading by means of the Central Institute for the Deaf (CID) sentence test 3 months postoperatively. Preoperative promontory stimulation results (thresholds, gap detection, and frequency discrimination), age, duration of profound deafness, cause of deafness, lipreading ability, postoperative intracochlear thresholds and dynamic ranges for electrical stimulation, depth of insertion of the electrode array into the scala tympani, and number of electrodes in use were considered as possible factors that might be related to the postoperative sentence scores. A multiple regression analysis with stepwise inclusion of independent variables indicated that good gap detection and frequency discrimination during preoperative promontory testing, larger numbers of electrodes in use, and greater dynamic ranges for intracochlear electrical stimulation were associated with better CID scores. The CID scores tended to decrease with longer periods of profound deafness.

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Electrical Cochlear Stimulation in the Deaf Cat: Comparisons Between Psychophysical and Central Auditory Neuronal Thresholds

Journal of Neurophysiology ◽

10.1152/jn.2000.83.4.2145 ◽

2000 ◽

Vol 83 (4) ◽

pp. 2145-2162 ◽

Cited By ~ 24

Author(s):

Ralph E. Beitel ◽

Russell L. Snyder ◽

Christoph E. Schreiner ◽

Marcia W. Raggio ◽

Patricia A. Leake

Keyword(s):

Electrical Stimulation ◽

Auditory System ◽

Pulse Rate ◽

Auditory Nerve ◽

Round Window ◽

Electrode Array ◽

Scala Tympani ◽

Behavioral Thresholds ◽

Current Pulses ◽

Stimulation Of

Cochlear prostheses for electrical stimulation of the auditory nerve (“electrical hearing”) can provide auditory capacity for profoundly deaf adults and children, including in many cases a restored ability to perceive speech without visual cues. A fundamental challenge in auditory neuroscience is to understand the neural and perceptual mechanisms that make rehabilitation of hearing possible in these deaf humans. We have developed a feline behavioral model that allows us to study behavioral and physiological variables in the same deaf animals. Cats deafened by injection of ototoxic antibiotics were implanted with either a monopolar round window electrode or a multichannel scala tympani electrode array. To evaluate the effects of perceptually significant electrical stimulation of the auditory nerve on the central auditory system, an animal was trained to avoid a mild electrocutaneous shock when biphasic current pulses (0.2 ms/phase) were delivered to its implanted cochlea. Psychophysical detection thresholds and electrical auditory brain stem response (EABR) thresholds were estimated in each cat. At the conclusion of behavioral testing, acute physiological experiments were conducted, and threshold responses were recorded for single neurons and multineuronal clusters in the central nucleus of the inferior colliculus (ICC) and the primary auditory cortex (A1). Behavioral and neurophysiological thresholds were evaluated with reference to cochlear histopathology in the same deaf cats. The results of the present study include: 1) in the cats implanted with a scala tympani electrode array, the lowest ICC and A1 neural thresholds were virtually identical to the behavioral thresholds for intracochlear bipolar stimulation; 2) behavioral thresholds were lower than ICC and A1 neural thresholds in each of the cats implanted with a monopolar round window electrode; 3) EABR thresholds were higher than behavioral thresholds in all of the cats (mean difference = 6.5 dB); and 4) the cumulative number of action potentials for a sample of ICC neurons increased monotonically as a function of the amplitude and the number of stimulating biphasic pulses. This physiological result suggests that the output from the ICC may be integrated spatially across neurons and temporally integrated across pulses when the auditory nerve array is stimulated with a train of biphasic current pulses. Because behavioral thresholds were lower and reaction times were faster at a pulse rate of 30 pps compared with a pulse rate of 2 pps, spatial-temporal integration in the central auditory system was presumably reflected in psychophysical performance.

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Evaluation of the Relationship between the NRT-Ratio, Cochlear Anatomy, and Insertions Depth of Perimodiolar Cochlear Implant Electrodes

BioMed Research International ◽

10.1155/2015/706253 ◽

2015 ◽

Vol 2015 ◽

pp. 1-6 ◽

Cited By ~ 6

Author(s):

Philipp Mittmann ◽

Grit Rademacher ◽

Sven Mutze ◽

Frederike Hassepass ◽

Arneborg Ernst ◽

...

Keyword(s):

Cochlear Implant ◽

Electrode Array ◽

Scala Tympani ◽

Flat Panel ◽

Insertion Depth ◽

Tomography System ◽

Neural Response Telemetry ◽

Auditory Performance ◽

The Relationship ◽

Scala Vestibuli

The position of the cochlear implant electrode array within the scala tympani is essential for an optimal postoperative hearing benefit. If the electrode array changes in between the scalae intracochlearly (i.e., from scala tympani to scala vestibuli), a reduced auditory performance can be assumed. We established a neural response telemetry-ratio (NRT-ratio) which corresponds with the scalar position of the electrodes but shows within its limits a variability. The aim of this study was to determine if insertion depth angle or cochlea size influences the NRT-ratio. The intraoperative electrophysiological NRT data of 26 patients were evaluated. Using a flat panel tomography system, the position of the electrode array was evaluated radiologically. The insertion depth angle of the electrode, the cochlea size, and the NRT-ratio were calculated postoperatively. The radiological results were compared with the intraoperatively obtained electrophysiological data (NRT-ratio) and statistically evaluated. In all patients the NRT-ratio, the insertion depth angle, and the cochlea size could be determined. A significant correlation between insertional depth, cochlear size, and the NRT-ratio was not found. The NRT-ratio is a reliable electrophysiological tool to determine the scalar position of a perimodiolar electrode array. The NRT-ratio can be applied independent from insertion depth and cochlear size.

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Histologic Evaluation of Temporal Bones with Cochlear Implants

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348948309200615 ◽

1983 ◽

Vol 92 (6) ◽

pp. 610-613 ◽

Cited By ~ 28

Author(s):

Fred H. Linthicum ◽

Frank R. Galey

Keyword(s):

Electrical Stimulation ◽

Cochlear Implant ◽

Cochlear Implants ◽

Ganglion Cells ◽

Scala Tympani ◽

Ectopic Bone ◽

Histologic Evaluation ◽

Temporal Bones ◽

Multiple Electrode

Ectopic bone in the scala tympani is characteristic of cochlear otosclerosis and meningitis, which are the two most frequent etiologies of deafness in cochlear implant patients. The ectopic bone in a multiple-electrode implanted bone is probably caused by disease (syphilis) rather than by the electrode or electrical stimulation. The sensory elements being stimulated by intracochlear electrodes probably are the ganglion cells.

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Clinical investigation of the Nucleus Slim Modiolar Electrode

Audiology and Neurotology ◽

10.1159/000480345 ◽

2017 ◽

Vol 22 (3) ◽

pp. 169-179 ◽

Cited By ~ 29

Author(s):

Antje Aschendorff ◽

Robert Briggs ◽

Goetz Brademann ◽

Silke Helbig ◽

Joachim Hornung ◽

...

Keyword(s):

Computed Tomography ◽

Cochlear Implant ◽

Temporal Bone ◽

Clinical Investigation ◽

Round Window ◽

Electrode Array ◽

Lateral Wall ◽

Scala Tympani ◽

Flat Panel ◽

Insertion Depth

Aims: The Nucleus CI532 cochlear implant incorporates a new precurved electrode array, i.e., the Slim Modiolar electrode (SME), which is designed to bring electrode contacts close to the medial wall of the cochlea while avoiding trauma due to scalar dislocation or contact with the lateral wall during insertion. The primary aim of this prospective study was to determine the final position of the electrode array in clinical cases as evaluated using flat-panel volume computed tomography. Methods: Forty-five adult candidates for unilateral cochlear implantation were recruited from 8 centers. Eleven surgeons attended a temporal bone workshop and received further training with a transparent plastic cochlear model just prior to the first surgery. Feedback on the surgical approach and use of the SME was collected via a questionnaire for each case. Computed tomography of the temporal bone was performed postoperatively using flat-panel digital volume tomography or cone beam systems. The primary measure was the final scalar position of the SME (completely in scala tympani or not). Secondly, medial-lateral position and insertion depth were evaluated. Results: Forty-four subjects received a CI532. The SME was located completely in scala tympani for all subjects. Pure round window (44% of the cases), extended round window (22%), and inferior and/or anterior cochleostomy (34%) approaches were successful across surgeons and cases. The SME was generally positioned close to the modiolus. Overinsertion of the array past the first marker tended to push the basal contacts towards the lateral wall and served only to increase the insertion depth of the first electrode contact without increasing the insertion depth of the most apical electrode. Complications were limited to tip fold-overs encountered in 2 subjects; both were attributed to surgical error, with both reimplanted successfully. Conclusions: The new Nucleus CI532 cochlear implant with SME achieved the design goal of producing little or no trauma as indicated by consistent scala tympani placement. Surgeons should be carefully trained to use the new deployment method such that tip fold-overs and over insertion may be avoided.

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Optimal Path Planning for Robotic Insertion of Steerable Electrode Arrays in Cochlear Implant Surgery

Journal of Medical Devices ◽

10.1115/1.3039513 ◽

2008 ◽

Vol 3 (1) ◽

Cited By ~ 27

Author(s):

Jian Zhang ◽

J. Thomas Roland ◽

Spiros Manolidis ◽

Nabil Simaan

Keyword(s):

Path Planning ◽

Cochlear Implant ◽

Optimal Path ◽

Electrode Array ◽

Scala Tympani ◽

Electrode Arrays ◽

Insertion Force ◽

Optimal Path Planning ◽

Cochlear Implant Surgery ◽

Electrode Insertion

This paper presents an optimal path planning method of steerable electrode arrays for robot-assisted cochlear implant surgery. In this paper, the authors present a novel design of steerable electrode arrays that can actively bend at the tip. An embedded strand in the electrode array provides an active steering degrees-of-freedom (DoF). This paper addresses the calibration of the steerable electrode array and the optimal path planning for inserting it into planar and three-dimensional scala tympani models. The goal of the path planning is to minimize the intracochlear forces that the electrode array applies on the walls of the scala tympani during insertion. This problem is solved by designing insertion path planning algorithms that provide best fit between the shape of the electrode array and the curved scala tympani during insertion. Optimality measures that account for shape discrepancies between the steerable electrode array and the scala tympani are used to solve for the optimal path planning of the robot. Different arrangements of DoF and insertion speed force feedback (ISFF) are simulated and experimentally validated in this paper. A quality of insertion metric describing the gap between the steerable electrode array and the scala tympani model is presented and its correspondence to the insertion force is shown. The results of using 1DoF, 2DoF, and 4DoF electrode array insertion setups are compared. The 1DoF insertion setup uses nonsteerable electrode arrays. The 2DoF insertion setup uses single axis insertion with steerable electrode arrays. The 4DoF insertion setup allows full control of the insertion depth and the approach angle of the electrode with respect to the cochlea while using steerable electrode arrays. It is shown that using steerable electrode arrays significantly reduces the maximal insertion force (59.6% or more) and effectively prevents buckling of the electrode array. The 4DoF insertion setup further reduces the maximal electrode insertion forces. The results of using ISFF for steerable electrodes show a slight decrease in the insertion forces in contrast to a slight increase for nonsteerable electrodes. These results show that further research is required in order to determine the optimal ISFF control law and its effectiveness in reducing electrode insertion forces.

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Refined Surgical Technique for Insertion of Banded Electrode Array

Annals of Otology Rhinology & Laryngology ◽

10.1177/00034894870960s105 ◽

1987 ◽

Vol 96 (1_suppl) ◽

pp. 15-17 ◽

Cited By ~ 12

Author(s):

B. K-H. G. Franz ◽

G. M. Clark

Keyword(s):

Surgical Technique ◽

Cochlear Implant ◽

Round Window ◽

Electrode Array ◽

Scala Tympani ◽

Insertion Technique ◽

Electrode Insertion ◽

The Right

A refined electrode insertion technique is presented for the multichannel cochlear implant. It comprises two basic steps. The first step is the removal of the anteroinferior overhang of the round window and crista fenestrae, or alternatively an opening drilled into the scala tympani anteroinferior to the round window. The second is rotation of the electrode during insertion, counterclockwise in the right ear and clockwise in the left ear.

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Microstructured thin-film electrode technology enables proof of concept of scalable, soft auditory brainstem implants

Science Translational Medicine ◽

10.1126/scitranslmed.aax9487 ◽

2019 ◽

Vol 11 (514) ◽

pp. eaax9487 ◽

Cited By ~ 8

Author(s):

Nicolas Vachicouras ◽

Osama Tarabichi ◽

Vivek V. Kanumuri ◽

Christina M. Tringides ◽

Jennifer Macron ◽

...

Keyword(s):

Electrical Stimulation ◽

Cochlear Implant ◽

Electrode Array ◽

Auditory Brainstem ◽

In Vivo Evaluation ◽

Anatomy And Physiology ◽

Complex Anatomy ◽

Auditory Brainstem Implants

Auditory brainstem implants (ABIs) provide sound awareness to deaf individuals who are not candidates for the cochlear implant. The ABI electrode array rests on the surface of the cochlear nucleus (CN) in the brainstem and delivers multichannel electrical stimulation. The complex anatomy and physiology of the CN, together with poor spatial selectivity of electrical stimulation and inherent stiffness of contemporary multichannel arrays, leads to only modest auditory outcomes among ABI users. Here, we hypothesized that a soft ABI could enhance biomechanical compatibility with the curved CN surface. We developed implantable ABIs that are compatible with surgical handling, conform to the curvature of the CN after placement, and deliver efficient electrical stimulation. The soft ABI array design relies on precise microstructuring of plastic-metal-plastic multilayers to enable mechanical compliance, patterning, and electrical function. We fabricated soft ABIs to the scale of mouse and human CN and validated them in vitro. Experiments in mice demonstrated that these implants reliably evoked auditory neural activity over 1 month in vivo. Evaluation in human cadaveric models confirmed compatibility after insertion using an endoscopic-assisted craniotomy surgery, ease of array positioning, and robustness and reliability of the soft electrodes. This neurotechnology offers an opportunity to treat deafness in patients who are not candidates for the cochlear implant, and the design and manufacturing principles are broadly applicable to implantable soft bioelectronics throughout the central and peripheral nervous system.

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Factors Affecting Outcomes in Cochlear Implant Recipients Implanted With a Perimodiolar Electrode Array Located in Scala Tympani

Otology & Neurotology ◽

10.1097/mao.0000000000001241 ◽

2016 ◽

Vol 37 (10) ◽

pp. 1662-1668 ◽

Cited By ~ 43

Author(s):

Laura K. Holden ◽

Jill B. Firszt ◽

Ruth M. Reeder ◽

Rosalie M. Uchanski ◽

Noël Y. Dwyer ◽

...

Keyword(s):

Cochlear Implant ◽

Electrode Array ◽

Scala Tympani ◽

Factors Affecting

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Maximizing Cochlear Implant Outcomes with Short-Term Aural Rehabilitation

Journal of the American Academy of Audiology ◽

10.1055/s-0041-1722987 ◽

2021 ◽

Author(s):

Claire Marcus Bernstein ◽

Diane Majerus Brewer ◽

Matthew H. Bakke ◽

Anne D. Olson ◽

Elizabeth Jackson Machmer ◽

...

Keyword(s):

Clinical Study ◽

Speech Recognition ◽

Cochlear Implant ◽

Active Control ◽

Analysis Of Variance ◽

Control Group ◽

Active Control Group ◽

Short Term ◽

Aural Rehabilitation ◽

Profound Deafness

Abstract Background Increasing numbers of adults are receiving cochlear implants (CIs) and many achieve high levels of speech perception and improved quality of life. However, a proportion of implant recipients still struggle due to limited speech recognition and/or greater communication demands in their daily lives. For these individuals a program of aural rehabilitation (AR) has the potential to improve outcomes. Purpose The study investigated the effects of a short-term AR intervention on speech recognition, functional communication, and psychosocial outcomes in post lingually deafened adult CI users. Research Design The experimental design was a multisite clinical study with participants randomized to either an AR treatment or active control group. Each group completed 6 weekly 90-minute individual treatment sessions. Assessments were completed pretreatment, 1 week and 2 months post-treatment. Study Sample Twenty-five post lingually deafened adult CI recipients participated. AR group: mean age 66.2 (48–80); nine females, four males; months postactivation 7.7 (3–16); mean years severe to profound deafness 18.4 (2–40). Active control group: mean age 62.8 (47–85); eight females, four males; months postactivation 7.0 (3–13); mean years severe to profound deafness 18.8 (1–55). Intervention The AR protocol consisted of auditory training (words, sentences, speech tracking), and psychosocial counseling (informational and communication strategies). Active control group participants engaged in cognitive stimulation activities (e.g., crosswords, sudoku, etc.). Data Collection and Analysis Repeated measures ANOVA or analysis of variance, MANOVA or multivariate analysis of variance, and planned contrasts were used to compare group performance on the following measures: CasperSent; Hearing Handicap Inventory; Nijmegen Cochlear Implant Questionnaire; Client Oriented Scale of Improvement; Glasgow Benefit Inventory. Results The AR group showed statistically significant improvements on speech recognition performance, psychosocial function, and communication goals with no significant improvement seen in the control group. The two groups were statistically equivalent on all outcome measures at preassessment. The robust improvements for the AR group were maintained at 2 months post-treatment. Conclusion Results of this clinical study provide evidence that a short-term AR intervention protocol can maximize outcomes for adult post lingually deafened CI users. The impact of this brief multidimensional AR intervention to extend CI benefit is compelling, and may serve as a template for best practices with adult CI users.

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