1
|
Burck I, Yel I, Martin S, Albrecht MH, Koch V, Booz C, Pinto Dos Santos D, Kaltenbach B, Ackermann H, Koivisto J, Helbig S, Stöver T, Vogl TJ, Scholtz JE. Comparison of 96-kV and 120-kV cone-beam CT for the assessment of cochlear implants. BMC Med Imaging 2024; 24:145. [PMID: 38872126 DOI: 10.1186/s12880-024-01322-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 06/04/2024] [Indexed: 06/15/2024] Open
Abstract
BACKGROUND To compare the diagnostic value of 120-kV with conventional 96-kV Cone-Beam CT (CBCT) of the temporal bone after cochlear implant (CI) surgery. METHODS This retrospective study included CBCT scans after CI surgery between 06/17 and 01/18. CBCT allowed examinations with 96-kV or 120-kV; other parameters were the same. Two radiologists independently evaluated following criteria on 5-point Likert scales: osseous spiral lamina, inner and outer cochlear wall, semi-circular canals, mastoid trabecular structure, overall image quality, metal and motion artefacts, depiction of intracochlear electrode position and visualisation of single electrode contacts. Effective radiation dose was assessed. RESULTS Seventy-five patients (females, n = 39 [52.0%], mean age, 55.8 ± 16.5 years) were scanned with 96-kV (n = 32, 42.7%) and 120-kV (n = 43, 57.3%) protocols including CI models from three vendors (vendor A n = 7; vendor B n = 43; vendor C n = 25). Overall image quality, depiction of anatomical structures, and electrode position were rated significantly better in 120-kV images compared to 96-kV (all p < = 0.018). Anatomical structures and electrode position were rated significantly better in 120-kV CBCT for CI models from vendor A and C, while 120-kV did not provide improved image quality in CI models from vendor B. Radiation doses were significantly higher for 120-kV scans compared to 96-kV (0.15 vs. 0.08 mSv, p < 0.001). CONCLUSIONS 120-kV and 96-kV CBCT provide good diagnostic images for the postoperative CI evaluation. While 120-kV showed improved depiction of temporal bone and CI electrode position compared to 96-kV in most CI models, the 120-kV protocol should be chosen wisely due to a substantially higher radiation exposure.
Collapse
Affiliation(s)
- Iris Burck
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany.
| | - Ibrahim Yel
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Simon Martin
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Moritz H Albrecht
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Vitali Koch
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Christian Booz
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Daniel Pinto Dos Santos
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Benjamin Kaltenbach
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Hanns Ackermann
- Institute of Biostatistics and Mathematical Modeling, University Hospital Frankfurt, Frankfurt, Germany
- Department of Otorhinolaryngology, University Hospital Frankfurt, Frankfurt, Germany
| | | | - Silke Helbig
- Department of Otorhinolaryngology, University Hospital Frankfurt, Frankfurt, Germany
| | - Timo Stöver
- Department of Otorhinolaryngology, University Hospital Frankfurt, Frankfurt, Germany
| | - Thomas J Vogl
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Jan-Erik Scholtz
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| |
Collapse
|
2
|
Lambriks L, van Hoof M, Debruyne J, Janssen M, Chalupper J, van der Heijden K, Hof J, Hellingman K, Devocht E, George E. Imaging-based frequency mapping for cochlear implants - Evaluated using a daily randomized controlled trial. Front Neurosci 2023; 17:1119933. [PMID: 37123376 PMCID: PMC10133468 DOI: 10.3389/fnins.2023.1119933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 03/03/2023] [Indexed: 05/02/2023] Open
Abstract
Background Due to variation in electrode design, insertion depth and cochlear morphology, patients with a cochlear implant (CI) often have to adapt to a substantial mismatch between the characteristic response frequencies of cochlear neurons and the stimulus frequencies assigned to electrode contacts. We introduce an imaging-based fitting intervention, which aimed to reduce frequency-to-place mismatch by aligning frequency mapping with the tonotopic position of electrodes. Results were evaluated in a novel trial set-up where subjects crossed over between intervention and control using a daily within-patient randomized approach, immediately from the start of CI rehabilitation. Methods Fourteen adult participants were included in this single-blinded, daily randomized clinical trial. Based on a fusion of pre-operative imaging and a post-operative cone beam CT scan (CBCT), mapping of electrical input was aligned to natural place-pitch arrangement in the individual cochlea. That is, adjustments to the CI's frequency allocation table were made so electrical stimulation of frequencies matched as closely as possible with corresponding acoustic locations in the cochlea. For a period of three months, starting at first fit, a scheme was implemented whereby the blinded subject crossed over between the experimental and standard fitting program using a daily randomized wearing schedule, and thus effectively acted as their own control. Speech outcomes (such as speech intelligibility in quiet and noise, sound quality and listening effort) were measured with both settings throughout the study period. Results On a group level, standard fitting obtained subject preference and showed superior results in all outcome measures. In contrast, two out of fourteen subjects preferred the imaging-based fitting and correspondingly had better speech understanding with this setting compared to standard fitting. Conclusion On average, cochlear implant fitting based on individual tonotopy did not elicit higher speech intelligibility but variability in individual results strengthen the potential for individualized frequency fitting. The novel trial design proved to be a suitable method for evaluation of experimental interventions in a prospective trial setup with cochlear implants.
Collapse
Affiliation(s)
- Lars Lambriks
- Department of ENT/Audiology, School for Mental Health and Neuroscience, Maastricht University Medical Centre, Maastricht, Netherlands
| | - Marc van Hoof
- Department of ENT/Audiology, School for Mental Health and Neuroscience, Maastricht University Medical Centre, Maastricht, Netherlands
| | - Joke Debruyne
- Department of ENT/Audiology, School for Mental Health and Neuroscience, Maastricht University Medical Centre, Maastricht, Netherlands
| | - Miranda Janssen
- Department of ENT/Audiology, School for Mental Health and Neuroscience, Maastricht University Medical Centre, Maastricht, Netherlands
- Department of Methodology and Statistics, Care and Public Health Research Institute, Maastricht University, Maastricht, Netherlands
| | - Josef Chalupper
- Advanced Bionics European Research Centre, Hannover, Germany
| | - Kiki van der Heijden
- Department of ENT/Audiology, School for Mental Health and Neuroscience, Maastricht University Medical Centre, Maastricht, Netherlands
| | - Janny Hof
- Department of ENT/Audiology, School for Mental Health and Neuroscience, Maastricht University Medical Centre, Maastricht, Netherlands
| | - Katja Hellingman
- Department of ENT/Audiology, School for Mental Health and Neuroscience, Maastricht University Medical Centre, Maastricht, Netherlands
| | - Elke Devocht
- Department of ENT/Audiology, School for Mental Health and Neuroscience, Maastricht University Medical Centre, Maastricht, Netherlands
| | - Erwin George
- Department of ENT/Audiology, School for Mental Health and Neuroscience, Maastricht University Medical Centre, Maastricht, Netherlands
| |
Collapse
|
3
|
Lambriks L, van Hoof M, Debruyne J, Janssen M, Hof J, Hellingman K, Devocht E, George E. Toward neural health measurements for cochlear implantation: The relationship among electrode positioning, the electrically evoked action potential, impedances and behavioral stimulation levels. Front Neurol 2023; 14:1093265. [PMID: 36846130 PMCID: PMC9948626 DOI: 10.3389/fneur.2023.1093265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 01/10/2023] [Indexed: 02/11/2023] Open
Abstract
Introduction Estimating differences in neural health across different sites within the individual cochlea potentially enables clinical applications for subjects with a cochlear implant. The electrically evoked compound action potential (ECAP) is a measure of neural excitability that possibly provides an indication of a neural condition. There are many factors, however, that affect this measure and increase the uncertainty of its interpretation. To better characterize the ECAP response, its relationship with electrode positioning, impedances, and behavioral stimulation levels was explored. Methods A total of 14 adult subjects implanted with an Advanced Bionics cochlear electrode array were prospectively followed up from surgery to 6 months postoperative. Insertion depth, distance to the modiolus, and distance to the medial wall were assessed for each electrode by postoperative CT analysis. ECAPs were measured intraoperatively and at three visits postoperatively on all 16 electrodes using the NRI feature of clinical programming software and characterized using multiple parameters. Impedances and behavioral stimulation levels were measured at every fitting session. Results Patterns in ECAPs and impedances were consistent over time, but high variability existed among subjects and between different positions in the cochlea. Electrodes located closer to the apex of the cochlea and closer to the modiolus generally showed higher neural excitation and higher impedances. Maximum loudness comfort levels were correlated strongly with the level of current needed to elicit a response of 100 μV ECAP. Conclusion Multiple factors contribute to the ECAP response in subjects with a cochlear implant. Further research might address whether the ECAP parameters used in this study will benefit clinical electrode fitting or the assessment of auditory neuron integrity.
Collapse
Affiliation(s)
- Lars Lambriks
- Department of ENT/Audiology, School for Mental Health and NeuroScience, Maastricht University Medical Centre, Maastricht, Netherlands,*Correspondence: Lars Lambriks ✉
| | - Marc van Hoof
- Department of ENT/Audiology, School for Mental Health and NeuroScience, Maastricht University Medical Centre, Maastricht, Netherlands
| | - Joke Debruyne
- Department of ENT/Audiology, School for Mental Health and NeuroScience, Maastricht University Medical Centre, Maastricht, Netherlands
| | - Miranda Janssen
- Department of ENT/Audiology, School for Mental Health and NeuroScience, Maastricht University Medical Centre, Maastricht, Netherlands,Department of Methodology and Statistics, Care and Public Health Research Institute, Maastricht University, Maastricht, Netherlands
| | - Janny Hof
- Department of ENT/Audiology, School for Mental Health and NeuroScience, Maastricht University Medical Centre, Maastricht, Netherlands
| | - Katja Hellingman
- Department of ENT/Audiology, School for Mental Health and NeuroScience, Maastricht University Medical Centre, Maastricht, Netherlands
| | - Elke Devocht
- Department of ENT/Audiology, School for Mental Health and NeuroScience, Maastricht University Medical Centre, Maastricht, Netherlands
| | - Erwin George
- Department of ENT/Audiology, School for Mental Health and NeuroScience, Maastricht University Medical Centre, Maastricht, Netherlands
| |
Collapse
|
4
|
Lambriks LJG, van Hoof M, Debruyne JA, Janssen M, Chalupper J, van der Heijden KA, Hof JR, Hellingman CA, George ELJ, Devocht EMJ. Evaluating hearing performance with cochlear implants within the same patient using daily randomization and imaging-based fitting - The ELEPHANT study. Trials 2020; 21:564. [PMID: 32576247 PMCID: PMC7310427 DOI: 10.1186/s13063-020-04469-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 05/30/2020] [Indexed: 02/08/2023] Open
Abstract
Background Prospective research in the field of cochlear implants is hampered by methodological issues and small sample sizes. The ELEPHANT study presents an alternative clinical trial design with a daily randomized approach evaluating individualized tonotopical fitting of a cochlear implant (CI). Methods A single-blinded, daily-randomized clinical trial will be implemented to evaluate a new imaging-based CI mapping strategy. A minimum of 20 participants will be included from the start of the rehabilitation process with a 1-year follow-up period. Based on a post-operative cone beam CT scan (CBCT), mapping of electrical input will be aligned to natural place-pitch arrangement in the individual cochlea. The CI’s frequency allocation table will be adjusted to match the electrical stimulation of frequencies as closely as possible to corresponding acoustic locations in the cochlea. A randomization scheme will be implemented whereby the participant, blinded to the intervention allocation, crosses over between the experimental and standard fitting program on a daily basis, and thus effectively acts as his own control, followed by a period of free choice between both maps to incorporate patient preference. With this new approach the occurrence of a first-order carryover effect and a limited sample size is addressed. Discussion The experimental fitting strategy is thought to give rise to a steeper learning curve, result in better performance in challenging listening situations, improve sound quality, better complement residual acoustic hearing in the contralateral ear and be preferred by recipients of a CI. Concurrently, the suitability of the novel trial design will be considered in investigating these hypotheses. Trial registration ClinicalTrials.gov: NCT03892941. Registered 27 March 2019.
Collapse
Affiliation(s)
- L J G Lambriks
- Department of ENT/Audiology, School for Mental Health and Neuroscience (MHeNs), Maastricht University Medical Center, Maastricht, The Netherlands.
| | - M van Hoof
- Department of ENT/Audiology, School for Mental Health and Neuroscience (MHeNs), Maastricht University Medical Center, Maastricht, The Netherlands
| | - J A Debruyne
- Department of ENT/Audiology, School for Mental Health and Neuroscience (MHeNs), Maastricht University Medical Center, Maastricht, The Netherlands
| | - M Janssen
- Department of ENT/Audiology, School for Mental Health and Neuroscience (MHeNs), Maastricht University Medical Center, Maastricht, The Netherlands.,Department of Methodology and Statistics, School for Public Health and Primary Care (CAPHRI), Maastricht University Medical Center, Maastricht, The Netherlands
| | - J Chalupper
- Advanced Bionics European Research Centre (AB ERC), Hannover, Germany
| | - K A van der Heijden
- Department of ENT/Audiology, School for Mental Health and Neuroscience (MHeNs), Maastricht University Medical Center, Maastricht, The Netherlands
| | - J R Hof
- Department of ENT/Audiology, School for Mental Health and Neuroscience (MHeNs), Maastricht University Medical Center, Maastricht, The Netherlands
| | - C A Hellingman
- Department of ENT/Audiology, School for Mental Health and Neuroscience (MHeNs), Maastricht University Medical Center, Maastricht, The Netherlands
| | - E L J George
- Department of ENT/Audiology, School for Mental Health and Neuroscience (MHeNs), Maastricht University Medical Center, Maastricht, The Netherlands
| | - E M J Devocht
- Department of ENT/Audiology, School for Mental Health and Neuroscience (MHeNs), Maastricht University Medical Center, Maastricht, The Netherlands
| |
Collapse
|
5
|
Peters JPM, Bennink E, van Zanten GA. Comparison of Place-versus-Pitch Mismatch between a Perimodiolar and Lateral Wall Cochlear Implant Electrode Array in Patients with Single-Sided Deafness and a Cochlear Implant. Audiol Neurootol 2019; 24:38-48. [PMID: 30995658 DOI: 10.1159/000499154] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 02/25/2019] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND In electric-acoustic pitch matching experiments in patients with single-sided deafness and a cochlear implant, the observed "mismatch" between perceived pitch and predicted pitch, based on the amended Greenwood frequency map, ranges from -1 to -2 octaves. It is unknown if and how this mismatch differs for perimodiolar versus lateral wall electrode arrays. OBJECTIVES We aimed to investigate if the type of electrode array design is of influence on the electric-acoustic pitch match. METHOD Fourteen patients (n = 8 with CI422 + lateral wall electrode array, n = 6 with CI512 + perimodiolar electrode array; Cochlear Ltd.) compared the pitch of acoustic stimuli to the pitch of electric stimuli at two test sessions (average interval 4.3 months). We plotted these "pitch matches" per electrode contact against insertion angle, calculated from high-resolution computed tomography scans. The difference between these pitch matches and two references (the spiral ganglion map and the default frequency allocation by Cochlear Ltd.) was defined as "mismatch." RESULTS We found average mismatches of -2.2 octaves for the CI422 group and -1.3 octaves for the CI512 group. For any given electrode contact, the mismatch was smaller for the CI512 electrode array than for the CI422 electrode array. For all electrode contacts together, there was a significant difference between the mismatches of the two groups (p < 0.05). Results remained stable over time, with no significant difference between the two test sessions considering all electrode contacts. Neither group showed a significant correlation between the mismatch and phoneme recognition scores. CONCLUSION The pitch mismatch was smaller for the perimodiolar electrode array than for the lateral wall electrode array.
Collapse
Affiliation(s)
- Jeroen P M Peters
- Department of Otorhinolaryngology and Head and Neck Surgery, University Medical Center Utrecht, Utrecht, The Netherlands, .,UMC Utrecht Brain Center, Utrecht, The Netherlands,
| | - Edwin Bennink
- Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Gijsbert A van Zanten
- Department of Otorhinolaryngology and Head and Neck Surgery, University Medical Center Utrecht, Utrecht, The Netherlands.,UMC Utrecht Brain Center, Utrecht, The Netherlands
| |
Collapse
|
6
|
Harczos T, Klefenz FM. Modeling Pitch Perception With an Active Auditory Model Extended by Octopus Cells. Front Neurosci 2018; 12:660. [PMID: 30319340 PMCID: PMC6167605 DOI: 10.3389/fnins.2018.00660] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Accepted: 09/04/2018] [Indexed: 11/13/2022] Open
Abstract
Pitch is an essential category for musical sensations. Models of pitch perception are vividly discussed up to date. Most of them rely on definitions of mathematical methods in the spectral or temporal domain. Our proposed pitch perception model is composed of an active auditory model extended by octopus cells. The active auditory model is the same as used in the Stimulation based on Auditory Modeling (SAM), a successful cochlear implant sound processing strategy extended here by modeling the functional behavior of the octopus cells in the ventral cochlear nucleus and by modeling their connections to the auditory nerve fibers (ANFs). The neurophysiological parameterization of the extended model is fully described in the time domain. The model is based on latency-phase en- and decoding as octopus cells are latency-phase rectifiers in their local receptive fields. Pitch is ubiquitously represented by cascaded firing sweeps of octopus cells. Based on the firing patterns of octopus cells, inter-spike interval histograms can be aggregated, in which the place of the global maximum is assumed to encode the pitch.
Collapse
Affiliation(s)
- Tamas Harczos
- Fraunhofer Institute for Digital Media Technology, Ilmenau, Germany
- Auditory Neuroscience and Optogenetics Laboratory, German Primate Center, Goettingen, Germany
- Institut für Mikroelektronik- und Mechatronik-Systeme gGmbH, Ilmenau, Germany
| | | |
Collapse
|
7
|
Caldwell MT, Jiam NT, Limb CJ. Assessment and improvement of sound quality in cochlear implant users. Laryngoscope Investig Otolaryngol 2017; 2:119-124. [PMID: 28894831 PMCID: PMC5527361 DOI: 10.1002/lio2.71] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Revised: 01/19/2017] [Accepted: 01/21/2017] [Indexed: 11/29/2022] Open
Abstract
Objectives Cochlear implants (CIs) have successfully provided speech perception to individuals with sensorineural hearing loss. Recent research has focused on more challenging acoustic stimuli such as music and voice emotion. The purpose of this review is to evaluate and describe sound quality in CI users with the purposes of summarizing novel findings and crucial information about how CI users experience complex sounds. Data Sources Here we review the existing literature on PubMed and Scopus to present what is known about perceptual sound quality in CI users, discuss existing measures of sound quality, explore how sound quality may be effectively studied, and examine potential strategies of improving sound quality in the CI population. Results Sound quality, defined here as the perceived richness of an auditory stimulus, is an attribute of implant‐mediated listening that remains poorly studied. Sound quality is distinct from appraisal, which is generally defined as the subjective likability or pleasantness of a sound. Existing studies suggest that sound quality perception in the CI population is limited by a range of factors, most notably pitch distortion and dynamic range compression. Although there are currently very few objective measures of sound quality, the CI‐MUSHRA has been used as a means of evaluating sound quality. There exist a number of promising strategies to improve sound quality perception in the CI population including apical cochlear stimulation, pitch tuning, and noise reduction processing strategies. Conclusions In the published literature, sound quality perception is severely limited among CI users. Future research should focus on developing systematic, objective, and quantitative sound quality metrics and designing therapies to mitigate poor sound quality perception in CI users. Level of Evidence NA
Collapse
Affiliation(s)
- Meredith T Caldwell
- Department of Otolaryngology-Head & Neck Surgery University of California San Francisco California
| | - Nicole T Jiam
- Department of Otolaryngology-Head & Neck Surgery University of California San Francisco California.,Johns Hopkins University School of Medicine Baltimore Maryland
| | - Charles J Limb
- Department of Otolaryngology-Head & Neck Surgery University of California San Francisco California
| |
Collapse
|
8
|
Peters JP, Bennink E, Grolman W, van Zanten GA. Electro-acoustic pitch matching experiments in patients with single-sided deafness and a cochlear implant. Hear Res 2016; 342:124-133. [DOI: 10.1016/j.heares.2016.10.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 10/07/2016] [Accepted: 10/15/2016] [Indexed: 11/25/2022]
|