1
|
Asfour L, Risi F, Treaba C, Kirk J, Roland Thomas J. Evaluation of a Slim Modiolar Electrode Array: A Temporal Bone Study. Otol Neurotol 2024; 45:870-877. [PMID: 39142309 DOI: 10.1097/mao.0000000000004253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/16/2024]
Abstract
HYPOTHESIS Evaluation of the Slim Modiolar (SM) electrode in temporal bones (TB) will elucidate the electrode's insertion outcomes. BACKGROUND The SM electrode was designed for atraumatic insertion into the scala tympani, for ideal perimodiolar positioning and with a smaller caliber to minimize interference with cochlear biological processes. METHODS The SM electrode was inserted into TBs via a cochleostomy. First, the axial force of insertion was measured. Next, TBs were inserted under fluoroscopy to study insertion dynamics, followed by histologic evaluation of electrode placement and cochlear trauma. A subset of TBs were inserted with the Contour Advance (CA) electrode for comparison. RESULTS Sixteen of 22 insertions performed to measure the axial force of insertion had flat or near zero insertion force profiles. Six insertions had increased insertion forces, which were attributed to improper sheath depth before electrode insertion. Under real-time fluoroscopy, 23 of 25 TBs had uneventful insertion and good perimodiolar placement. There was 1 scala vestibuli insertion due to suboptimal cochleostomy position and 1 tip roll over related to premature electrode deployment. When compared with the CA electrode, 14 of 15 insertions with the SM electrode resulted in a more perimodiolar electrode position. No evidence of trauma was found in histologic evaluation of the 24 TBs with scala tympani insertions. CONCLUSION TB evaluation revealed that the SM electrode exerts minimal insertion forces on cochlear structures, produces no histologic evidence of trauma, and reliably assumes the perimodiolar position. Nonstandard cochleostomy location, improper sheath insertion depth, or premature deployment of the electrode may lead to suboptimal outcomes.
Collapse
Affiliation(s)
- Leena Asfour
- Department of Otolaryngology, New York University School of Medicine, New York, U.S.A
| | | | | | | | - J Roland Thomas
- Department of Otolaryngology, New York University School of Medicine, New York, U.S.A
| |
Collapse
|
2
|
Hrnčiřík F, Nagy L, Grimes HL, Iftikhar H, Muzaffar J, Bance M. Impact of Insertion Speed, Depth, and Robotic Assistance on Cochlear Implant Insertion Forces and Intracochlear Pressure: A Scoping Review. SENSORS (BASEL, SWITZERLAND) 2024; 24:3307. [PMID: 38894099 PMCID: PMC11174543 DOI: 10.3390/s24113307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Revised: 05/13/2024] [Accepted: 05/14/2024] [Indexed: 06/21/2024]
Abstract
Cochlear implants are crucial for addressing severe-to-profound hearing loss, with the success of the procedure requiring careful electrode placement. This scoping review synthesizes the findings from 125 studies examining the factors influencing insertion forces (IFs) and intracochlear pressure (IP), which are crucial for optimizing implantation techniques and enhancing patient outcomes. The review highlights the impact of variables, including insertion depth, speed, and the use of robotic assistance on IFs and IP. Results indicate that higher insertion speeds generally increase IFs and IP in artificial models, a pattern not consistently observed in cadaveric studies due to variations in methodology and sample size. The study also explores the observed minimal impact of robotic assistance on reducing IFs compared to manual methods. Importantly, this review underscores the need for a standardized approach in cochlear implant research to address inconsistencies and improve clinical practices aimed at preserving hearing during implantation.
Collapse
Affiliation(s)
- Filip Hrnčiřík
- Cambridge Hearing Group, Cambridge CB2 7EF, UK; (F.H.)
- Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0QQ, UK
| | - Leo Nagy
- Clinical School, University of Cambridge, Cambridge CB2 0QQ, UK
| | | | - Haissan Iftikhar
- Department of Otolaryngology, University Hospitals Birmingham, Birmingham B15 2TT, UK
| | - Jameel Muzaffar
- Cambridge Hearing Group, Cambridge CB2 7EF, UK; (F.H.)
- Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0QQ, UK
- Department of Otolaryngology, University Hospitals Birmingham, Birmingham B15 2TT, UK
| | - Manohar Bance
- Cambridge Hearing Group, Cambridge CB2 7EF, UK; (F.H.)
- Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0QQ, UK
| |
Collapse
|
3
|
Dhanasingh A, Nielsen SB, Beal F, Schilp S, Hessler R, Jolly C, Hochmair I. Cochlear implant electrode design for safe and effective treatment. Front Neurol 2024; 15:1348439. [PMID: 38756216 PMCID: PMC11096578 DOI: 10.3389/fneur.2024.1348439] [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: 12/02/2023] [Accepted: 04/09/2024] [Indexed: 05/18/2024] Open
Abstract
The optimal placement of a cochlear implant (CI) electrode inside the scala tympani compartment to create an effective electrode-neural interface is the base for a successful CI treatment. The characteristics of an effective electrode design include (a) electrode matching every possible variation in the inner ear size, shape, and anatomy, (b) electrically covering most of the neuronal elements, and (c) preserving intra-cochlear structures, even in non-hearing preservation surgeries. Flexible electrode arrays of various lengths are required to reach an angular insertion depth of 680° to which neuronal cell bodies are angularly distributed and to minimize the rate of electrode scalar deviation. At the time of writing this article, the current scientific evidence indicates that straight lateral wall electrode outperforms perimodiolar electrode by preventing electrode tip fold-over and scalar deviation. Most of the available literature on electrode insertion depth and hearing outcomes supports the practice of physically placing an electrode to cover both the basal and middle turns of the cochlea. This is only achievable with longer straight lateral wall electrodes as single-sized and pre-shaped perimodiolar electrodes have limitations in reaching beyond the basal turn of the cochlea and in offering consistent modiolar hugging placement in every cochlea. For malformed inner ear anatomies that lack a central modiolar trunk, the perimodiolar electrode is not an effective electrode choice. Most of the literature has failed to demonstrate superiority in hearing outcomes when comparing perimodiolar electrodes with straight lateral wall electrodes from single CI manufacturers. In summary, flexible and straight lateral wall electrode type is reported to be gentle to intra-cochlear structures and has the potential to electrically stimulate most of the neuronal elements, which are necessary in bringing full benefit of the CI device to recipients.
Collapse
|
4
|
Varghese JJ, Walia A, Lefler SM, Ortmann AJ, Shew MA, Durakovic N, Wick CC, Herzog JA, Buchman CA. Identifying Slim Modiolar Electrode Tip Fold-Over With Intracochlear Electrocochleography. Otolaryngol Head Neck Surg 2024; 170:1124-1132. [PMID: 38018567 PMCID: PMC10960700 DOI: 10.1002/ohn.587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 10/21/2023] [Accepted: 10/28/2023] [Indexed: 11/30/2023]
Abstract
OBJECTIVE To evaluate the predictive value of intracochlear electrocochleography (ECochG) for identifying tip fold-over during cochlear implantation (CI) using the slim modiolar electrode (SME) array. STUDY DESIGN Prospective cohort study. SETTING Tertiary referral center. METHODS From July 2022 to June 2023, 142 patients, including adults and children, underwent intracochlear ECochG monitoring during and after SME placement. Tone-bursts were presented from 250 Hz to 2 kHz at 108 to 114 dB HL. A fast Fourier transform (FFT) allowed for frequency-specific evaluation of ECochG response. ECochG patterns during insertion and postinsertion were evaluated using sensitivity and specificity analysis to predict tip fold-over. Intraoperative plain radiographs served as a reference standard. RESULTS Fifteen tip fold-over cases occurred (10.6%) with significant ECochG response (>2 µV). Sixty-one cases without tip fold-over occurred (43.0%) with significant ECochG response. All tip fold-overs had both a nontonotopic postinsertion sweep and nonrobust active insertion pattern. No patients with robust insertion or tonotopic sweep patterns had tip fold-over. Sensitivity of detecting tip fold-over when having both nonrobust insertion and nontonotopic sweep patterns was 100% (95% confidence inteval [CI] 78.2%-100%), specificity was 68.9% (95% CI 55.7%-80.1%), and the overall accuracy was 72.0% (95% CI 60.5%-81.7%). CONCLUSION Intracochlear ECochG monitoring during cochlear implantation with the SME can be a valuable tool for identifying properly positioned electrode arrays. In cases where ECochG patterns are nonrobust on insertion and nontonotopic for electrode sweeps, there may be a concern for tip fold-over, and intraoperative imaging is necessary to confirm proper insertion.
Collapse
Affiliation(s)
- Jordan J. Varghese
- Department of Otolaryngology – Head and Neck Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Amit Walia
- Department of Otolaryngology – Head and Neck Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Shannon M. Lefler
- Department of Otolaryngology – Head and Neck Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Amanda J. Ortmann
- Department of Otolaryngology – Head and Neck Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Matthew A. Shew
- Department of Otolaryngology – Head and Neck Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Nedim Durakovic
- Department of Otolaryngology – Head and Neck Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Cameron C. Wick
- Department of Otolaryngology – Head and Neck Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Jacques A. Herzog
- Department of Otolaryngology – Head and Neck Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Craig A. Buchman
- Department of Otolaryngology – Head and Neck Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
| |
Collapse
|
5
|
Beck R, Aschendorff A, Arndt S, Hildenbrand T, Rauch AK, Ketterer MC. Evaluation of insertion quality of a slim perimodiolar electrode array. Eur Arch Otorhinolaryngol 2024; 281:1215-1220. [PMID: 37773530 PMCID: PMC10858093 DOI: 10.1007/s00405-023-08212-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 08/25/2023] [Indexed: 10/01/2023]
Abstract
OBJECTIVES The influence of cochlear morphology and electrode array design on scalar position and dislocation rates is of great interest in CI surgery. The aim of this study is to evaluate scalar position and specific points of dislocation in relation to cochlear morphology in patients implanted with a new slim perimodiolar electrode array. MATERIALS AND METHODS Patients were implanted using the slim modiolar electrode array (= SMA) (= 532/632 electrode array of Cochlear™). Postoperative imaging was performed via cone beam computed tomography (CBCT) and the scans were analyzed regarding cochlear morphology (distances A and B and cochlear height), scalar location of the electrode array, basal insertion depth and apical insertion angle. Furthermore, electrode array design and surgical protocols were evaluated. RESULTS 81 ears implanted with the SMA were retrospectively included. We evaluated 3 electrode array tip fold over intraoperatively via X-ray imaging and performed revision during the same surgery. The CBCT scans showed 76 initial scala tympani (ST) insertions without dislocation. Two ears showed a dislocated array, one at 77° and the other at 163°. Three arrays were inserted into scala vestibuli (SV) via cochleostomy. These patients showed no signs of obliteration. Cochlear morphology showed no influence on angular insertion depth and scalar position. CONCLUSIONS The SMA showed a very low rate of scalar dislocations due to its slim electrode array design (2.7%). We could find a learning curve regarding the handling and the risk of dislocation and tip fold over with this electrode array. The rate of intraoperative tip fold over detection via X-ray imaging was 3.7%. Therefore, we highly recommend X-ray imaging and transimpedance matrix measurements within the surgery protocol. Scala vestibuli insertions happened in patients with cochleostomy only. We could identify two specific points of dislocation depending on electrode array design.
Collapse
Affiliation(s)
- R Beck
- Faculty of Medicine, Department of Otorhinolaryngology, Medical Center - University of Freiburg, University of Freiburg, Freiburg, Germany
| | - A Aschendorff
- Faculty of Medicine, Department of Otorhinolaryngology, Medical Center - University of Freiburg, University of Freiburg, Freiburg, Germany
| | - S Arndt
- Faculty of Medicine, Department of Otorhinolaryngology, Medical Center - University of Freiburg, University of Freiburg, Freiburg, Germany
| | - T Hildenbrand
- Faculty of Medicine, Department of Otorhinolaryngology, Medical Center - University of Freiburg, University of Freiburg, Freiburg, Germany
| | - A K Rauch
- Faculty of Medicine, Department of Otorhinolaryngology, Medical Center - University of Freiburg, University of Freiburg, Freiburg, Germany
| | - M C Ketterer
- Faculty of Medicine, Department of Otorhinolaryngology, Medical Center - University of Freiburg, University of Freiburg, Freiburg, Germany.
- Department of Otorhinolaryngology - Head and Neck Surgery, University of Freiburg, Killianstrasse 5, 79106, Freiburg, Germany.
| |
Collapse
|
6
|
Geerardyn A, Zhu M, Verhaert N, Quesnel AM. Intracochlear Trauma and Local Ossification Patterns Differ Between Straight and Precurved Cochlear Implant Electrodes. Otol Neurotol 2024; 45:245-255. [PMID: 38270168 PMCID: PMC10922381 DOI: 10.1097/mao.0000000000004102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2024]
Abstract
HYPOTHESIS Trauma to the osseous spiral lamina (OSL) or spiral ligament (SL) during cochlear implant (CI) insertion segregates with electrode type and induces localized intracochlear ossification and fibrosis. BACKGROUND The goal of atraumatic CI insertion is to preserve intracochlear structures, limit reactive intracochlear tissue formation, and preserve residual hearing. Previous qualitative studies hypothesized a localized effect of trauma on intracochlear tissue formation; however, quantitative studies failed to confirm this. METHODS Insertional trauma beyond the immediate insertion site was histologically assessed in 21 human temporal bones with a CI. Three-dimensional reconstructions were generated and virtually resectioned perpendicular to the cochlear spiral at high resolution. The cochlear volume occupied by ossification or fibrosis was determined at the midpoint of the trauma and compared with regions proximal and distal to this point. RESULTS Seven cases, all implanted with precurved electrodes, showed an OSL fracture beyond the immediate insertion site. Significantly more intracochlear ossification was observed at the midpoint of the OSL fracture, compared with the -26 to -18 degrees proximal and 28 to 56 degrees distal to the center. No such pattern was observed for fibrosis. In the 12 cases with a perforation of the SL (9 straight and 3 precurved electrodes), no localized pattern of ossification or fibrosis was observed around these perforations. CONCLUSION OSL fractures were observed exclusively with precurved electrodes in this study and may serve as a nidus for localized intracochlear ossification. Perforation of the SL, in contrast, predominantly occurred with straight electrodes and was not associated with localized ossification.
Collapse
Affiliation(s)
| | - MengYu Zhu
- Otopathology Laboratory, Massachusetts Eye and Ear, Boston, Massachusetts, USA
| | | | | |
Collapse
|
7
|
Starovoyt A, Shaheen E, Putzeys T, Kerckhofs G, Politis C, Wouters J, Verhaert N. Anatomically and mechanically accurate scala tympani model for electrode insertion studies. Hear Res 2023; 430:108707. [PMID: 36773540 DOI: 10.1016/j.heares.2023.108707] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 11/25/2022] [Accepted: 01/24/2023] [Indexed: 01/26/2023]
Abstract
The risk of insertion trauma in cochlear implantation is determined by the interplay between individual cochlear anatomy and electrode insertion mechanics. Whereas patient anatomy cannot be changed, new surgical techniques, devices for cochlear monitoring, drugs, and electrode array designs are continuously being developed and tested, to optimize the insertion mechanics and prevent trauma. Preclinical testing of these developments is a crucial step in feasibility testing and optimization for clinical application. Human cadaveric specimens allow for the best simulation of an intraoperative setting. However, their availability is limited and it is not possible to conduct repeated, controlled experiments on the same sample. A variety of artificial cochlear models have been developed for electrode insertion studies, but none of them were both anatomically and mechanically representative for surgical insertion into an individual cochlea. In this study, we developed anatomically representative models of the scala tympani for surgical insertion through the round window, based on microCT images of individual human cochleae. The models were produced in transparent material using commonly-available 3D printing technology at a desired scale. The anatomical and mechanical accuracy of the produced models was validated by comparison with human cadaveric cochleae. Mechanical evaluation was performed by recording insertion forces, counting the number of inserted electrodes and grading tactile feedback during manual insertion of a straight electrode by experienced cochlear implant surgeons. Our results demonstrated that the developed models were highly representative for the anatomy of the original cochleae and for the insertion mechanics in human cadaveric cochleae. The individual anatomy of the produced models had a significant impact on the insertion mechanics. The described models have a promising potential to accelerate preclinical development and testing of atraumatic insertion techniques, reducing the need for human cadaveric material. In addition, realistic models of the cochlea can be used for surgical training and preoperative planning of patient-tailored cochlear implantation surgery.
Collapse
Affiliation(s)
- Anastasiya Starovoyt
- Research Group Experimental Oto-Rhino-Laryngology, Department of Neurosciences, KU Leuven, University of Leuven, Leuven, Belgium; Leuven Brain Institute, Department of Neurosciences, KU Leuven, 3000 Leuven, Belgium
| | - Eman Shaheen
- OMFS IMPATH Research Group, Department of Imaging and Pathology, KU Leuven, University of Leuven, Leuven, Belgium; Department of Oral and Maxillofacial Surgery, UZ Leuven, University Hospitals Leuven, Leuven, Belgium
| | - Tristan Putzeys
- Research Group Experimental Oto-Rhino-Laryngology, Department of Neurosciences, KU Leuven, University of Leuven, Leuven, Belgium; Leuven Brain Institute, Department of Neurosciences, KU Leuven, 3000 Leuven, Belgium; Laboratory for Soft Matter and Biophysics, Department of Physics and Astronomy, KU Leuven, University of Leuven, Leuven, Belgium
| | - Greet Kerckhofs
- Biomechanics lab, Institute of Mechanics, Materials, and Civil Engineering, UCLouvain, Louvain-la-Neuve, Belgium; Department of Materials Engineering, KU Leuven, University of Leuven, Leuven, Belgium; IREC, Institute of Experimental and Clinical Research, UCLouvain, Woluwé-Saint-Lambert, Belgium; Prometheus, Division of Skeletal Tissue Engineering, KU Leuven, University of Leuven, Leuven, Belgium
| | - Constantinus Politis
- OMFS IMPATH Research Group, Department of Imaging and Pathology, KU Leuven, University of Leuven, Leuven, Belgium; Department of Oral and Maxillofacial Surgery, UZ Leuven, University Hospitals Leuven, Leuven, Belgium
| | - Jan Wouters
- Research Group Experimental Oto-Rhino-Laryngology, Department of Neurosciences, KU Leuven, University of Leuven, Leuven, Belgium; Leuven Brain Institute, Department of Neurosciences, KU Leuven, 3000 Leuven, Belgium
| | - Nicolas Verhaert
- Research Group Experimental Oto-Rhino-Laryngology, Department of Neurosciences, KU Leuven, University of Leuven, Leuven, Belgium; Leuven Brain Institute, Department of Neurosciences, KU Leuven, 3000 Leuven, Belgium; Department of Otorhinolaryngology, Head and Neck Surgery, UZ Leuven, University Hospitals of Leuven, Leuven, Belgium.
| |
Collapse
|
8
|
Human cochlear microstructures at risk of electrode insertion trauma, elucidated in 3D with contrast-enhanced microCT. Sci Rep 2023; 13:2191. [PMID: 36750646 PMCID: PMC9905077 DOI: 10.1038/s41598-023-29401-6] [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: 10/14/2022] [Accepted: 02/03/2023] [Indexed: 02/09/2023] Open
Abstract
Cochlear implant restores hearing loss through electrical stimulation of the hearing nerve from within the cochlea. Unfortunately, surgical implantation of this neuroprosthesis often traumatizes delicate intracochlear structures, resulting in loss of residual hearing and compromising hearing in noisy environments and appreciation of music. To avoid cochlear trauma, insertion techniques and devices have to be adjusted to the cochlear microanatomy. However, existing techniques were unable to achieve a representative visualization of the human cochlea: classical histology damages the tissues and lacks 3D perspective; standard microCT fails to resolve the cochlear soft tissues; and previously used X-ray contrast-enhancing staining agents are destructive. In this study, we overcame these limitations by performing contrast-enhanced microCT imaging (CECT) with a novel polyoxometalate staining agent Hf-WD POM. With Hf-WD POM-based CECT, we achieved nondestructive, high-resolution, simultaneous, 3D visualization of the mineralized and soft microstructures in fresh-frozen human cochleae. This enabled quantitative analysis of the true intracochlear dimensions and led to anatomical discoveries, concerning surgically-relevant microstructures: the round window membrane, the Rosenthal's canal and the secondary spiral lamina. Furthermore, we demonstrated that Hf-WD POM-based CECT enables quantitative assessment of these structures as well as their trauma.
Collapse
|
9
|
Inoue T, Tona Y, Okano T, Omori K, Yamamoto N. Detection of Tip Fold-Over of the Slim Modiolar Electrode Using Intraoperative Mobile Cone-Beam Computed Tomography. Otolaryngol Head Neck Surg 2023. [PMID: 36939567 DOI: 10.1002/ohn.240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 11/17/2022] [Accepted: 12/10/2022] [Indexed: 01/26/2023]
Abstract
OBJECTIVE This study aimed to evaluate the importance of mobile cone-beam computed tomography in detecting tip fold-over of a slim modiolar electrode within the cochlea during surgery. STUDY DESIGN Retrospective case review. SETTING Tertiary medical center. METHODS From January 2020 to June 2022, 33 ears of 30 patients with normal cochlear morphology underwent cochlear implantation with slim modiolar electrodes and intraoperative mobile cone-beam computed tomography imaging. Furthermore, we retrospectively reviewed the medical records and images. RESULTS The tip fold-over of the electrodes was detected using mobile cone-beam computed tomography in 3 out of 33 ears (9.1%). We could not identify the tip fold-over by scouting plain X-ray images in 2 out of 3 cases before taking the cone-beam computed tomography images. Electrode removal and reinsertion were performed before wound closure and the successful reinsertion was confirmed by mobile cone-beam computed tomography. The folded electrode tips were located at 238.8°, 152°, and 185.8°. CONCLUSION Intraoperative mobile cone-beam computed tomography is useful in detecting the tip fold-over of the slim modiolar electrodes during surgery. Therefore, it was possible to reinsert the electrodes in all cases before closing the wound, eliminating the need for revision surgeries. Moreover, the analysis of mobile cone-beam computed tomography images may help to elucidate the mechanisms of electrode tip fold-over.
Collapse
Affiliation(s)
- Taishi Inoue
- Department of Otolaryngology, Japanese Red Cross Wakayama Medical Center, Wakayama, Japan
| | - Yosuke Tona
- Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Takayuki Okano
- Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Koichi Omori
- Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Norio Yamamoto
- Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.,Department of Otolaryngology, Kobe City Medical Center General Hospital, Kobe, Hyogo, Japan
| |
Collapse
|
10
|
Slim Modiolar Electrode Placement in Candidates for Electroacoustic Stimulation. Ear Hear 2022; 44:566-571. [PMID: 36534657 DOI: 10.1097/aud.0000000000001304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
OBJECTIVES To determine rates of hearing preservation and performance in patients who met candidacy for electroacoustic stimulation (EAS) and were implanted with a slim modiolar electrode (CI532 or CI632). DESIGN Adult patients meeting Food and Drug Administration criteria for electroacoustic stimulation (preoperative low-frequency pure-tone average [LFPTA] less than 60 dB at 125, 250, and 500 Hz and monosyllabic word scores between 10% and 60% in the ear to be implanted), who received a slim modiolar electrode were included. Main outcome measures included rates of hearing preservation, defined as a LFPTA ≤80 dB at 125, 250, and 500 Hz, as well as postoperative low-frequency pure-tone threshold shifts, consonant-Nucleus-Consonant (CNC) word scores and AzBio sentences in noise scores. RESULTS Forty-six patients met inclusion criteria during a 4-year period. Mean (standard deviation) preoperative LFPTA was 34.5 (13.0) dB, and 71.7% had preserved hearing at initial activation. The mean LFPTA shift in patients who preserved hearing at initial activation was 19.7 (14.6) dB, compared with 62.6 (17.7) dB in patients who did not preserve hearing as per our definition. Perioperative steroid use was not different in patients with and without preserved hearing (X 2 (1, N = 46) = 0.19, p = .67, V = 0.06). One year after surgery, 57% of patients had a decline in LFPTA >80 dB and were no longer considered candidates for EAS, with 34.7% still retaining low-frequency thresholds ≤80 dB. CNC word scores at 1 year were 69.9% and 61.4% among individuals with and without preserved low-frequency hearing respectively, measured in their CI ear alone, in their regular listening condition of EAS or electric only ( t (32) = 1.13, p = 0.27, d = 0.39, 95% CI = -6.51, 22.86). Device use time did not differ between groups. Among adults with preserved residual hearing at 1 year (n = 16), 44% used EAS, although there was no significant difference in performance between EAS users and nonusers with preserved hearing. Loss of residual hearing over time did not result in a decline in speech perception performance. CONCLUSION The present study demonstrated favorable early rates of hearing preservation with a slim modiolar array. Performance was not significantly different in individuals with and without preserved low-frequency acoustic hearing, independent of EAS use. Compared with reports of short electrode use, the loss of residual hearing in patients implanted with this array did not impact speech perception performance.
Collapse
|
11
|
Leblans M, Zarowski A, Molisz A, van Dinther J, Dedeyne J, Lerut B, Kuhweide R, Offeciers E. Cochlear implant electrode array tip-foldover detection by electrode voltage telemetry. Cochlear Implants Int 2022:1-12. [DOI: 10.1080/14670100.2022.2148890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Affiliation(s)
- Marc Leblans
- European Institute for ORL, GZA Sint-Augustinus, Antwerp, Belgium
| | - Andrzej Zarowski
- European Institute for ORL, GZA Sint-Augustinus, Antwerp, Belgium
| | - Andrzej Molisz
- Department of Family Medicine, Medical University of Gdansk, Gdańsk, Poland
| | | | - Janne Dedeyne
- ENT Department, AZ Sint-Jan Brugge-Oostende, Brugge, Belgium
| | - Bob Lerut
- ENT Department, AZ Sint-Jan Brugge-Oostende, Brugge, Belgium
| | - Rudolf Kuhweide
- ENT Department, AZ Sint-Jan Brugge-Oostende, Brugge, Belgium
| | - Erwin Offeciers
- European Institute for ORL, GZA Sint-Augustinus, Antwerp, Belgium
| |
Collapse
|
12
|
Starovoyt A, Quirk BC, Putzeys T, Kerckhofs G, Nuyts J, Wouters J, McLaughlin RA, Verhaert N. An optically-guided cochlear implant sheath for real-time monitoring of electrode insertion into the human cochlea. Sci Rep 2022; 12:19234. [PMID: 36357503 PMCID: PMC9649659 DOI: 10.1038/s41598-022-23653-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 11/03/2022] [Indexed: 11/12/2022] Open
Abstract
In cochlear implant surgery, insertion of perimodiolar electrode arrays into the scala tympani can be complicated by trauma or even accidental translocation of the electrode array within the cochlea. In patients with partial hearing loss, cochlear trauma can not only negatively affect implant performance, but also reduce residual hearing function. These events have been related to suboptimal positioning of the cochlear implant electrode array with respect to critical cochlear walls of the scala tympani (modiolar wall, osseous spiral lamina and basilar membrane). Currently, the position of the electrode array in relation to these walls cannot be assessed during the insertion and the surgeon depends on tactile feedback, which is unreliable and often comes too late. This study presents an image-guided cochlear implant device with an integrated, fiber-optic imaging probe that provides real-time feedback using optical coherence tomography during insertion into the human cochlea. This novel device enables the surgeon to accurately detect and identify the cochlear walls ahead and to adjust the insertion trajectory, avoiding collision and trauma. The functionality of this prototype has been demonstrated in a series of insertion experiments, conducted by experienced cochlear implant surgeons on fresh-frozen human cadaveric cochleae.
Collapse
Affiliation(s)
- Anastasiya Starovoyt
- grid.5596.f0000 0001 0668 7884Department of Neurosciences, ExpORL, KU Leuven, 3000 Leuven, Belgium ,grid.5596.f0000 0001 0668 7884Department of Neurosciences, Leuven Brain Institute, KU Leuven, 3000 Leuven, Belgium
| | - Bryden C. Quirk
- grid.1010.00000 0004 1936 7304Australian Research Council Centre of Excellence for Nanoscale BioPhotonics, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, SA 5005 Australia ,grid.1010.00000 0004 1936 7304Institute for Photonics and Advanced Sensing, The University of Adelaide, Adelaide, SA 5005 Australia
| | - Tristan Putzeys
- grid.5596.f0000 0001 0668 7884Department of Neurosciences, ExpORL, KU Leuven, 3000 Leuven, Belgium ,grid.5596.f0000 0001 0668 7884Department of Neurosciences, Leuven Brain Institute, KU Leuven, 3000 Leuven, Belgium ,grid.5596.f0000 0001 0668 7884Laboratory for Soft Matter and Biophysics, Department of Physics and Astronomy, KU Leuven, 3000 Leuven, Belgium
| | - Greet Kerckhofs
- grid.7942.80000 0001 2294 713XBiomechanics Laboratory, Institute of Mechanics, Materials, and Civil Engineering, UCLouvain, 1348 Louvain-La-Neuve, Belgium ,grid.5596.f0000 0001 0668 7884Department of Materials Science and Engineering, KU Leuven, 3000 Leuven, Belgium ,grid.7942.80000 0001 2294 713XInstitute of Experimental and Clinical Research, UCLouvain, 1200 Woluwé-Saint-Lambert, Belgium ,grid.5596.f0000 0001 0668 7884Prometheus, Division of Skeletal Tissue Engineering, KU Leuven, 3000 Leuven, Belgium
| | - Johan Nuyts
- grid.5596.f0000 0001 0668 7884Department of Imaging and Pathology, Division of Nuclear Medicine, KU Leuven, 3000 Leuven, Belgium ,Nuclear Medicine and Molecular Imaging, Medical Imaging Research Center, 3000 Leuven, Belgium
| | - Jan Wouters
- grid.5596.f0000 0001 0668 7884Department of Neurosciences, ExpORL, KU Leuven, 3000 Leuven, Belgium ,grid.5596.f0000 0001 0668 7884Department of Neurosciences, Leuven Brain Institute, KU Leuven, 3000 Leuven, Belgium
| | - Robert A. McLaughlin
- grid.1010.00000 0004 1936 7304Australian Research Council Centre of Excellence for Nanoscale BioPhotonics, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, SA 5005 Australia ,grid.1010.00000 0004 1936 7304Institute for Photonics and Advanced Sensing, The University of Adelaide, Adelaide, SA 5005 Australia ,grid.1012.20000 0004 1936 7910School of Engineering, University of Western Australia, Perth, WA 6009 Australia
| | - Nicolas Verhaert
- grid.5596.f0000 0001 0668 7884Department of Neurosciences, ExpORL, KU Leuven, 3000 Leuven, Belgium ,grid.5596.f0000 0001 0668 7884Department of Neurosciences, Leuven Brain Institute, KU Leuven, 3000 Leuven, Belgium ,grid.410569.f0000 0004 0626 3338Department of Otorhinolaryngology, Head and Neck Surgery, University Hospitals of Leuven, 3000 Leuven, Belgium
| |
Collapse
|
13
|
Matsumoto N, Akagi-Tsuchihashi N, Noda T, Komune N, Nakagawa T. Orientation of the Cochlea From a Surgeon's Perspective. OTOLOGY & NEUROTOLOGY OPEN 2022; 2:e017. [PMID: 38516627 PMCID: PMC10950153 DOI: 10.1097/ono.0000000000000017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 06/23/2022] [Indexed: 03/23/2024]
Abstract
Background One of the mechanisms that cause tip fold-over is a misalignment between the electrode array's coiling direction and the cochlea's curving direction. Objectives We reviewed surgical videos and computed tomography (CT) datasets of the patients who underwent cochlear implantation procedures from January 2010 to December 2021, paying particular attention to the cochlea's orientation in the surgeon's microscopic view. Methods CT dataset and video recordings were analyzed to measure the "slope angle," which is the angle between the cochlea's coiling plane and the horizontal plane. Results There were 220 cases that met the criteria and completed the analysis. The mean slope angle was 12.1° ± 9.5°, with a minimum of -9.4° and maximum of 44.6°. However, each surgeon had a favored slope angle range. Conclusion Understanding the slope angle and making an effort to reduce the chance of misalignment during electrode insertion may help prevent tip fold-over of slim perimodiolar electrode arrays.
Collapse
Affiliation(s)
- Nozomu Matsumoto
- Department of Otorhinolaryngology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Nana Akagi-Tsuchihashi
- Department of Otorhinolaryngology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Teppei Noda
- Department of Otorhinolaryngology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Noritaka Komune
- Department of Otorhinolaryngology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Takashi Nakagawa
- Department of Otorhinolaryngology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| |
Collapse
|
14
|
Van de Heyning P, Roland P, Lassaletta L, Agrawal S, Atlas M, Baumgartner WD, Brown K, Caversaccio M, Dazert S, Gstoettner W, Hagen R, Hagr A, Jablonski GE, Kameswaran M, Kuzovkov V, Leinung M, Li Y, Loth A, Magele A, Mlynski R, Mueller J, Parnes L, Radeloff A, Raine C, Rajan G, Schmutzhard J, Skarzynski H, Skarzynski PH, Sprinzl G, Staecker H, Stöver T, Tavora-Viera D, Topsakal V, Usami SI, Van Rompaey V, Weiss NM, Wimmer W, Zernotti M, Gavilan J. Suitable Electrode Choice for Robotic-Assisted Cochlear Implant Surgery: A Systematic Literature Review of Manual Electrode Insertion Adverse Events. Front Surg 2022; 9:823219. [PMID: 35402479 PMCID: PMC8987358 DOI: 10.3389/fsurg.2022.823219] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 02/09/2022] [Indexed: 12/05/2022] Open
Abstract
Background and Objective The cochlear implant (CI) electrode insertion process is a key step in CI surgery. One of the aims of advances in robotic-assisted CI surgery (RACIS) is to realize better cochlear structure preservation and to precisely control insertion. The aim of this literature review is to gain insight into electrode selection for RACIS by acquiring a thorough knowledge of electrode insertion and related complications from classic CI surgery involving a manual electrode insertion process. Methods A systematic electronic search of the literature was carried out using PubMed, Scopus, Cochrane, and Web of Science to find relevant literature on electrode tip fold over (ETFO), electrode scalar deviation (ESD), and electrode migration (EM) from both pre-shaped and straight electrode types. Results A total of 82 studies that include 8,603 ears implanted with a CI, i.e., pre-shaped (4,869) and straight electrodes (3,734), were evaluated. The rate of ETFO (25 studies, 2,335 ears), ESD (39 studies, 3,073 ears), and EM (18 studies, 3,195 ears) was determined. An incidence rate (±95% CI) of 5.38% (4.4-6.6%) of ETFO, 28.6% (26.6-30.6%) of ESD, and 0.53% (0.2-1.1%) of EM is associated with pre-shaped electrodes, whereas with straight electrodes it was 0.51% (0.1-1.3%), 11% (9.2-13.0%), and 3.2% (2.5-3.95%), respectively. The differences between the pre-shaped and straight electrode types are highly significant (p < 0.001). Laboratory experiments show evidence that robotic insertions of electrodes are less traumatic than manual insertions. The influence of round window (RW) vs. cochleostomy (Coch) was not assessed. Conclusion Considering the current electrode designs available and the reported incidence of insertion complications, the use of straight electrodes in RACIS and conventional CI surgery (and manual insertion) appears to be less traumatic to intracochlear structures compared with pre-shaped electrodes. However, EM of straight electrodes should be anticipated. RACIS has the potential to reduce these complications.
Collapse
Affiliation(s)
- Paul Van de Heyning
- Department of Otorhinolaryngology Head and Neck Surgery, Antwerp University Hospital, University of Antwerp, Antwerp, Belgium
- Department of Translational Neurosciences, University of Antwerp, Antwerp, Belgium
| | - Peter Roland
- Department of Otolaryngology, Head & Neck Surgery, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Luis Lassaletta
- Hospital Universitario La Paz, Institute for Health Research (IdiPAZ), Madrid, Spain
| | - Sumit Agrawal
- Department of Otolaryngology-Head and Neck Surgery, Western University, London, ON, Canada
| | - Marcus Atlas
- Ear Sciences Institute Australia, Lions Hearing Clinic, Perth, WA, Australia
| | | | - Kevin Brown
- UNC Ear and Hearing Center at Chapel Hill School of Medicine, Chapel Hill, NC, United States
| | - Marco Caversaccio
- Department for ENT, Head and Neck Surgery, Bern University Hospital, Bern, Switzerland
| | - Stefan Dazert
- Department of Otorhinolaryngology-Head and Neck Surgery, Ruhr-University Bochum, St. Elisabeth University Hospital Bochum, Bochum, Germany
| | | | - Rudolf Hagen
- Würzburg ENT University Hospital, Würzburg, Germany
| | - Abdulrahman Hagr
- King Abdullah Ear Specialist Center, King Saud University Medical City, King Saud University, Riyadh, Saudi Arabia
| | - Greg Eigner Jablonski
- Institute of Clinical Medicine, University of Oslo, Oslo, Norway
- Department of Otorhinolaryngology & Head and Neck Surgery, Oslo University Hospital, Rikshospitalet, Oslo, Norway
| | | | - Vladislav Kuzovkov
- St. Petersburg ENT and Speech Research Institute, St. Petersburg, Russia
| | - Martin Leinung
- Department of Otolaryngology, Head and Neck Surgery, University Hospital Frankfurt, Frankfurt am Main, Germany
| | - Yongxin Li
- Department of Otorhinolaryngology Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University, Beijing, China
- Key Laboratory of Otolaryngology Head and Neck Surgery (Capital Medical University), Ministry of Education, Beijing, China
| | - Andreas Loth
- Department of Otolaryngology, Head and Neck Surgery, University Hospital Frankfurt, Frankfurt am Main, Germany
| | - Astrid Magele
- Ear, Nose and Throat Department, University Clinic St. Poelten, Karl Landsteiner Private University, St. Poelten, Austria
| | - Robert Mlynski
- Department of Otorhinolaryngology, Head and Neck Surgery, “Otto Körner” Rostock University Medical Center, Rostock, Germany
| | - Joachim Mueller
- Klinik und Poliklinik für Hals-, Nasen- und Ohrenheilkunde, Ludwig-Maximilians-Universitat Munchen, Munchen, Germany
| | - Lorne Parnes
- Department of Otolaryngology-Head and Neck Surgery, Western University, London, ON, Canada
| | - Andreas Radeloff
- Division of Oto-Rhino-Laryngology, Evangelisches Krankenhaus Oldenburg, Research Center of Neurosensory Sciences, University Oldenburg, Oldenburg, Germany
| | - Chris Raine
- Bradford Royal Infirmary Yorkshire Auditory Implant Center, Bradford, United Kingdom
| | - Gunesh Rajan
- Department of Otolaryngology, Head and Neck Surgery, Luzerner Kantonsspital, Luzern, Medical Sciences Department of Health Sciences and Medicine. University of Lucerne, Luzern, Switzerland. Otolaryngology, Head & Neck Surgery, Medical School University of Western Australia, Perth, WA, Australia
| | - Joachim Schmutzhard
- Department of Otorhinolaryngology, Medical University of Innsbruck, Innsbruck, Austria
| | - Henryk Skarzynski
- Department of Teleaudiology and Screening, World Hearing Center of the Institute of Physiology and Pathology of Hearing, Kajetany, Poland
| | - Piotr H. Skarzynski
- Department of Teleaudiology and Screening, World Hearing Center of the Institute of Physiology and Pathology of Hearing, Kajetany, Poland
| | - Georg Sprinzl
- Ear, Nose and Throat Department, University Clinic St. Poelten, Karl Landsteiner Private University, St. Poelten, Austria
| | - Hinrich Staecker
- Kansas University Center for Hearing and Balance Disorders, Kansas City, KS, United States
| | - Timo Stöver
- Department of Otolaryngology, Head and Neck Surgery, University Hospital Frankfurt, Frankfurt am Main, Germany
| | | | - Vedat Topsakal
- Department of ENT HNS, University Hospital Brussels, Brussels, Belgium
| | - Shin-Ichi Usami
- Department of Hearing Implant Sciences, Shinshu University School of Medicine, Nagano, Japan
| | - Vincent Van Rompaey
- Department of Otorhinolaryngology Head and Neck Surgery, Antwerp University Hospital, University of Antwerp, Antwerp, Belgium
- Department of Translational Neurosciences, University of Antwerp, Antwerp, Belgium
| | - Nora M. Weiss
- Department of Otorhinolaryngology-Head and Neck Surgery, Ruhr-University Bochum, St. Elisabeth University Hospital Bochum, Bochum, Germany
| | - Wilhelm Wimmer
- Department for ENT, Head and Neck Surgery, Bern University Hospital, Bern, Switzerland
| | - Mario Zernotti
- Catholic University of Córdoba and National University of Córdoba, Córdoba, Argentina
| | - Javier Gavilan
- Hospital Universitario La Paz, Institute for Health Research (IdiPAZ), Madrid, Spain
| |
Collapse
|
15
|
Variations in microanatomy of the human modiolus require individualized cochlear implantation. Sci Rep 2022; 12:5047. [PMID: 35322066 PMCID: PMC8943032 DOI: 10.1038/s41598-022-08731-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 03/10/2022] [Indexed: 11/09/2022] Open
Abstract
Cochlear variability is of key importance for the clinical use of cochlear implants, the most successful neuroprosthetic device that is surgically placed into the cochlear scala tympani. Despite extensive literature on human cochlear variability, few information is available on the variability of the modiolar wall. In the present study, we analyzed 108 corrosion casts, 95 clinical cone beam computer tomographies (CTs) and 15 µCTs of human cochleae and observed modiolar variability of similar and larger extent than the lateral wall variability. Lateral wall measures correlated with modiolar wall measures significantly. ~ 49% of the variability had a common cause. Based on these data we developed a model of the modiolar wall variations and related the model to the design of cochlear implants aimed for perimodiolar locations. The data demonstrate that both the insertion limits relevant for lateral wall damage (approximate range of 4–9 mm) as well as the dimensions required for optimal perimodiolar placement of the electrode (the point of release from the straightener; approximate range of 2–5mm) are highly interindividually variable. The data demonstrate that tip fold-overs of preformed implants likely result from the morphology of the modiolus (with radius changing from base to apex), and that optimal cochlear implantation of perimodiolar arrays cannot be guaranteed without an individualized surgical technique.
Collapse
|
16
|
Intracochlear New Fibro-Ossification and Neuronal Degeneration Following Cochlear Implant Electrode Translocation: Long-Term Histopathological Findings in Humans. Otol Neurotol 2022; 43:e153-e164. [PMID: 35015749 DOI: 10.1097/mao.0000000000003402] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
OBJECTIVE We aim to assess the histopathology of human temporal bones (TBs) with evidence of cochlear implantation (CI) electrode scalar translocation. STUDY DESIGN Otopathology study. SETTING Otopathology laboratory. PATIENTS TBs from patients who had a history of CI and histopathological evidence of interscalar translocation. Specimens with electrode placed entirely within the ST served as controls. INTERVENTION Histopathological assessment of human TBs. MAIN OUTCOME MEASURES TBs from each patient were harvested postmortem and histologically analyzed for intracochlear changes in the context of CI electrode translocation and compared to controls. Intracochlear new fibro-ossification, and spiral ganglion neuron (SGN) counts were assessed. Postoperative word recognition scores (WRS) were also compared. RESULTS Nineteen human TBs with electrode translocation and eight controls were identified. The most common site of translocation was the ascending limb of the basal turn (n = 14 TBs). The average angle of insertion at the point of translocation was 159° ± 79°. Eighteen translocated cases presented moderate fibroosseous changes in the basal region of the cochlea, extending to the translocation point and/or throughout the electrode track in 42%. Lower SGN counts were more pronounced in translocated cases compared to controls, with a significant difference for segment II (p = 0.019). Although final postoperative hearing outcomes were similar between groups, translocated cases had slower rate of improvement in WRS (p = 0.021). CONCLUSIONS Cochlear implant electrode translocation was associated with greater fibroosseous formation and lower SGN population. Our findings suggest that scalar translocations may slow the rate of improvement in WRS overtime as compared to atraumatic electrode insertions.Level of evidence: IV.
Collapse
|
17
|
Högerle C, Englhard A, Simon F, Grüninger I, Mlynski R, Hempel JM, Müller J. Cochlear Implant Electrode Tip Fold-Over: Our Experience With Long and Flexible Electrode. Otol Neurotol 2022; 43:64-71. [PMID: 34619728 DOI: 10.1097/mao.0000000000003362] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE The aim of this study was to retrospectively investigate if there is any incidence of electrode tip fold-over with 31.5 mm long and flexible lateral wall electrodes implanted in two high-volume Cochlear Implant (CI) centers in Germany. In addition, a detailed literature review was performed to capture all the peer-reviewed publications reporting on tip fold-over with CI electrodes from different CI brands for comparison. METHODS Post-operative X-ray images of FLEX SOFT electrode from MED-EL in Stenver's view were retrospectively investigated for the presence of electrode tip fold-over from 378 consecutive cases in two high-volume CI centers in Germany. All patients were implanted between 2010 and 2018 by three individual experienced CI surgeons using round window and extended round window approach for CI electrode insertion. A literature review was performed following a thorough PubMed (https://www.ncbi.nlm.nih.gov/pubmed/) search using the keywords "cochlear implant electrode tip fold-over" or "cochlear implant electrode tip roll-over" to capture articles that were published until December 2020 in English language only. Articles selection was based on electrode-related issues investigated only in-patient cases applying imaging modality. Those studies investigated tip fold-over in cadaveric temporal bones and cases with inner-ear malformation excluded. RESULTS No single case of tip fold-over was clinically detected from the retrospective investigation of post-operative X-ray images from 378 consecutive cases. The electrode angular insertion depth as measured applying the cochlear coordinate system, varied from a minimum of 560° to a maximum of 720°. The literature review on the tip fold-over issue resulted in 24 peer-reviewed published articles in total. Tip fold-over with pre-curved modiolar-hugging electrodes was reported in 85 cases out of 1,606 implantations making an incidence rate of 5.3%. With the straight lateral wall electrodes, the tip fold-over was reported in four cases out of 398 implantations making an incidence rate of 1%, not including the number of implantations reported in the current study. Otherwise it would be 0.5%. CONCLUSION Electrode tip fold-over with 31.5 mm long flexible lateral wall electrodes is highly exceptional and this can be generalized to any of the straight lateral wall electrodes from any CI brand. The literature review on tip fold-over revealed an incidence rate of 5.3% with pre-curved or modiolar-hugging electrodes and 1% with straight lateral wall electrodes from CI brands. Including this series of 0% tip fold-over, the incidence rate of electrode tip fold-over with LW electrode type would be 0.5%.
Collapse
Affiliation(s)
- Catalina Högerle
- Department of Otorhinolaryngology, Head and Neck Surgery, Ludwig Maximilians University, Munich
| | - Anna Englhard
- Department of Otorhinolaryngology, Head and Neck Surgery, Ludwig Maximilians University, Munich
| | - Florian Simon
- Department of Otorhinolaryngology, Head and Neck Surgery, Ludwig Maximilians University, Munich
| | - Ivo Grüninger
- Department of Otorhinolaryngology, Head and Neck Surgery, Ludwig Maximilians University, Munich
| | - Robert Mlynski
- Department of Otorhinolaryngology, Head and Neck Surgery "Otto Körner," Rostock University Medical Center, Rostock, Germany
| | - John-Martin Hempel
- Department of Otorhinolaryngology, Head and Neck Surgery, Ludwig Maximilians University, Munich
| | - Joachim Müller
- Department of Otorhinolaryngology, Head and Neck Surgery, Ludwig Maximilians University, Munich
| |
Collapse
|
18
|
Liebscher T, Mewes A, Hoppe U, Hornung J, Brademann G, Hey M. Electrode Translocations in Perimodiolar Cochlear Implant Electrodes: Audiological and Electrophysiological Outcome. Z Med Phys 2021; 31:265-275. [DOI: 10.1016/j.zemedi.2020.05.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 04/16/2020] [Accepted: 05/05/2020] [Indexed: 10/24/2022]
|
19
|
Slim, Modiolar Cochlear Implant Electrode: Melbourne Experience and Comparison With the Contour Perimodiolar Electrode. Otol Neurotol 2021; 41:639-643. [PMID: 32150026 DOI: 10.1097/mao.0000000000002617] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To describe the tip fold over rate, scalar localization, and speech perception outcomes of the CI532 Slim Modiolar Electrode. PATIENTS AND INTERVENTION All patients receiving the CI532 implant before June 2018. MAIN OUTCOME MEASURES Outcome measures for adults patients include pre- and postoperative speech perception, operative report details, electrode position as determined by X-ray and cone beam computed tomography. Comparison made with previous experience with the Contour perimodiolar electrode (CI512). In the pediatric population tip fold-over rate, measured by intraoperative X-ray, was the exclusive outcome. RESULTS One hundred twenty-five CI532 devices were implanted in adults and 69 in children. Electrode tip fold-over occurred in eight adults cases and none among children (4.1%). Cone beam CT scans of 120 out of 125 adult patients confirmed scala tympani (ST) position in all but one case where the electrode had been placed into scala vestibuli. There were no translocations from ST to scala vestibuli. This compares favorably with the CI512 translocation rate of 17%. Speech perception outcomes demonstrated good performance with mean preop phoneme scores of 16.2% (±13) increasing to 64.2% (±14) and 71.6 (±16) 3 and 12-months postop, respectively. Compared with a matched group of CI512 recipients, CI532 recipient phoneme scores were significantly higher 3 and 12-months postop by 4 and 7%, respectively. CONCLUSION The slim modiolar, CI532 electrode has provided very reliable ST position with a low rate of tip fold over. A trend toward better speech perception scores in CI532 compared with CI512 was observed.
Collapse
|
20
|
Copson B, Wijewickrema S, Ma X, Zhou Y, Gerard JM, O'Leary S. Surgical approach to the facial recess influences the acceptable trajectory of cochlear implantation electrodes. Eur Arch Otorhinolaryngol 2021; 279:137-147. [PMID: 33547488 DOI: 10.1007/s00405-021-06633-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 01/20/2021] [Indexed: 11/29/2022]
Abstract
PURPOSE To provide practical guidance to the operative surgeon by mapping the location, where acceptable straight-line virtual cochlear implant electrode trajectories intersect the facial recess. In addition, to investigate the influence of facial recess preparation, virtual electrode width and surgical approach to the cochlea on these available trajectories. METHODS The study was performed on imaging data from eight cadaveric temporal bones within the University of Melbourne Virtual Reality (VR) Temporal Bone Surgery Simulator. The facial recess was opened to varying degrees, and acceptable trajectory vectors with varying diameters were calculated for electrode insertions via cochleostomy or round window membrane (RWM). The percentage of acceptable insertion vectors through each location of the facial recess was visually represented using heatmaps. RESULTS Seven of the eight bones allowed for acceptable vector trajectories via both cochleostomy and RWM approaches. These acceptable trajectories were more likely to lie superiorly within the facial recess for insertion via the round window, and inferiorly for insertion via cochleostomy. Cochleostomy insertions required a greater degree of preparation and skeletonisation of the junction of the facial nerve and chorda tympani within the facial recess. The width of the virtual electrode had only marginal impact on the availability of acceptable trajectories. Heatmaps emphasised the intimate relationship the acceptable trajectories have with the facial nerve and chorda tympani. CONCLUSION These findings highlight the differences in the acceptable straight-line trajectories for electrodes when implanted via the round window or cochleostomy. There were notable exceptions to both surgical approaches, likely explained by the variation of hook region anatomy. The methodology used in this study holds promise for translation to patient specific surgical planning.
Collapse
Affiliation(s)
- Bridget Copson
- Department of Surgery (Otolaryngology), University of Melbourne, Level 5, Royal Victorian Eye and Ear Hospital, 32, Gisborne Street, East Melbourne, VIC, 3002, Australia.
| | - Sudanthi Wijewickrema
- Department of Surgery (Otolaryngology), University of Melbourne, Level 5, Royal Victorian Eye and Ear Hospital, 32, Gisborne Street, East Melbourne, VIC, 3002, Australia
| | - Xingjun Ma
- Department of Surgery (Otolaryngology), University of Melbourne, Level 5, Royal Victorian Eye and Ear Hospital, 32, Gisborne Street, East Melbourne, VIC, 3002, Australia
| | - Yun Zhou
- Department of Surgery (Otolaryngology), University of Melbourne, Level 5, Royal Victorian Eye and Ear Hospital, 32, Gisborne Street, East Melbourne, VIC, 3002, Australia
| | - Jean-Marc Gerard
- Department of Surgery (Otolaryngology), University of Melbourne, Level 5, Royal Victorian Eye and Ear Hospital, 32, Gisborne Street, East Melbourne, VIC, 3002, Australia
| | - Stephen O'Leary
- Department of Surgery (Otolaryngology), University of Melbourne, Level 5, Royal Victorian Eye and Ear Hospital, 32, Gisborne Street, East Melbourne, VIC, 3002, Australia
| |
Collapse
|
21
|
Radiological evaluation of a new straight electrode array compared to its precursors. Eur Arch Otorhinolaryngol 2020; 278:3707-3714. [PMID: 33090276 PMCID: PMC8382647 DOI: 10.1007/s00405-020-06434-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 10/10/2020] [Indexed: 11/24/2022]
Abstract
Objective The aim of this study is to examine electrode array coverage, scalar position and dislocation rate in straight electrode arrays with special focus on a new electrode array with 26 mm in lengths. Study design Retrospective study. Setting Tertiary academic center. Patients 201 ears implanted between 2013 and 2019. Main outcome measures We conducted a comparative analysis of patients implanted with lateral wall electrode arrays of different lengths (F24 = MED-EL Flex24, F26 = MED-EL Flex26, F28 = MED-EL Flex28 and F31.5 = MED-EL FlexSoft). Cone beam computed tomography was used to determine electrode array position (scala tympani (ST) versus scala vestibuli (SV), intracochlear dislocation, position of dislocation and insertion angle). Results Study groups show no significant differences regarding cochlear size which excludes influences by cochlear morphology. As expected, the F24 showed significant shorter insertion angles compared to the longer electrode arrays. The F26 electrode array showed no signs of dislocation or SV insertion. The electrode array with the highest rate of ST dislocations was the F31.5 (26.3%). The electrode array with the highest rates of SV insertions was the F28 (5.75%). Most of the included electrode arrays dislocate between 320° and 360° (mean: 346.4°; range from 166° to 502°). Conclusion The shorter F24 and the new straight electrode array F26 show less or no signs of scalar dislocation, neither for round window nor for cochleostomy insertion than the longer F28 and the F31.5 array. As expected, the cochlear coverage is increasing with length of the electrode array itself but with growing risk for scalar dislocation and with the highest rates of dislocation for the longest electrode array F31.5. Position of intracochlear dislocation is in the apical cochlear part in the included lateral wall electrode arrays.
Collapse
|
22
|
Durakovic N, Kallogjeri D, Wick CC, McJunkin JL, Buchman CA, Herzog J. Immediate and 1-Year Outcomes with a Slim Modiolar Cochlear Implant Electrode Array. Otolaryngol Head Neck Surg 2020; 162:731-736. [PMID: 32180504 DOI: 10.1177/0194599820907336] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE To explore the immediate and 1-year outcomes of patients who underwent implantation with the slim modiolar electrode (SME). STUDY DESIGN Consecutive case series with chart review. SETTING Tertiary referral academic center. SUBJECT AND METHODS Between May 2016 and August 2018, a total of 326 cochlear implantations (CIs) were performed. Intraoperative x-rays were performed in all cases to identify tip rollovers. Scalar location was identified for 76 CIs that had postoperative computed tomography reconstructions. Speech outcomes were measured at 3, 6, and 12 months with consonant-nucleus-consonant word and AzBio sentences in quiet and noise (+10-dB signal-to-noise ratio). Preservation of hearing was defined as maintaining a low-frequency pure tone average ≤80 dB at 250 and 500 Hz. RESULTS Among 326 CIs, 23 (7%) had tip rollovers. Postoperative reconstructions revealed 5 of 76 (6.6%) scalar translocations. A subset of 177 cases met criteria for evaluation of speech perception scores. The marginal mean differences between presurgery and 12 months for speech tests were as follows: consonant-nucleus-consonant, 43.7 (95% CI, 39.8-47.6); AzBio in quiet, 49.7 (95% CI, 44.9-54.4); and AzBio in noise, 29.9 (95% CI, 25.2-34.7). Sixty-one patients were identified with preservable hearing (low-frequency pure tone average ≤80 dB), and 12 of 61 (20%) preserved hearing at 1 year. CONCLUSION CI with SME provides reliable scala tympani insertion in a consistent perimodiolar position. An initially increased tip rollover rate improved with case volume and sheath design improvement. For long-term outcomes, speech performance was comparable to that of other cochlear implants. While hearing preservation for the SME may be better than prior perimodiolar electrodes, consistent outcomes are unlikely.
Collapse
Affiliation(s)
- Nedim Durakovic
- Department of Otolaryngology-Head and Neck Surgery, Washington University School of Medicine in St Louis, St Louis, Missouri, USA
| | - Dorina Kallogjeri
- Department of Otolaryngology-Head and Neck Surgery, Washington University School of Medicine in St Louis, St Louis, Missouri, USA
| | - Cameron C Wick
- Department of Otolaryngology-Head and Neck Surgery, Washington University School of Medicine in St Louis, St Louis, Missouri, USA
| | - Jonathan L McJunkin
- Department of Otolaryngology-Head and Neck Surgery, Washington University School of Medicine in St Louis, St Louis, Missouri, USA
| | - Craig A Buchman
- Department of Otolaryngology-Head and Neck Surgery, Washington University School of Medicine in St Louis, St Louis, Missouri, USA
| | - Jacques Herzog
- Department of Otolaryngology-Head and Neck Surgery, Washington University School of Medicine in St Louis, St Louis, Missouri, USA
| |
Collapse
|
23
|
Vadivelu AN, Liu Z, Gunawardena DS, Chen B, Tam HY, O'Leary S, Oetomo D. Integrated Force Sensor in a Cochlear Implant for Hearing Preservation Surgery. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2020; 2019:3819-3822s. [PMID: 31946706 DOI: 10.1109/embc.2019.8856549] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Cochlear Implant is used for patients with severe hearing loss. It is a neural-prosthesis that stimulates the nerve endings within the cochlea, which is the organ of hearing. The surgical technique involves inserting the electrode array of the implant into a very small "snail-like" spiral structure. During this insertion process, the surgeon's finger tip is not able to perceive the resistance from the contact of the implant and the cochlea's internal structure, below the internal rupture threshold. This can potentially damage vital structures and result in the worsening of residual hearing and poor speech perception. Currently, there is no clinically and commercially available intra-operative force feedback system. A custom made sensor is therefore proposed, integrated within the implant to enable real-time force readings. The device will provide surgeons with the vital force feedback information related to the implants' position within the cochlea. This paper concentrates on demonstrating that the proposed sensor is capable of measuring the contact force below the rupture threshold of the cochlea's internal structure.
Collapse
|
24
|
Iso-Mustajärvi M, Sipari S, Lehtimäki A, Tervaniemi J, Löppönen H, Dietz A. A New Application of CBCT Image Fusion in Temporal Bone Studies. J Int Adv Otol 2019; 15:431-435. [PMID: 31846925 DOI: 10.5152/iao.2019.7365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVES Temporal bone (TB) studies are essential during the development of new arrays. Postoperative cochlear histology is still regarded as golden standard for the assessment of electrode localization and trauma though it is time consuming, expensive and technically very demanding. The aim of this study is to investigate whether pre-operative evacuation of perilymph improve the assessment of electrode localization and insertion trauma in TBs applying fusion imaging. The results were compared to a prior validated image fusion technique based on the quantification of the electrode placement. MATERIALS AND METHODS 12 prototype electrodes were implanted in fresh frozen TBs. The perilymph was evacuated from the scale prior to pre-operative cone-beam computer tomography (CBCT). The TB were then immersed in Ringer solution to rehydrated both scalae. After electrode insertion post-operative CBCT were obtained. 3D fusions of the pre- and postoperative registration were reconstructed. The electrode localization with respect to the basilar membrane was visually assessed. RESULTS The visualization of the BM on the pre-operative scans was achieved beyond the second turn in all TBs. The visual assessment was found to be as accurate as the previously validated fusion technique. There was no statistically significant difference between the methods (p=0.564). The image reconstructions and evaluations, however, were faster to perform and the insertion results are immediately available. CONCLUSION CBCT in combination with pre- and postoperative image fusion is an accurate method for the post-operative assessment of insertion trauma in TBs. This new application facilitates the identification of the BM and allows for a visual assessment of insertion trauma.
Collapse
Affiliation(s)
- Matti Iso-Mustajärvi
- Department of Otorhinolaryngology - Head and Neck Surgery, Kuopio University Hospital, Kuopio, Finland
| | - Sini Sipari
- Department of Otorhinolaryngology - Head and Neck Surgery, Kuopio University Hospital, Kuopio, Finland
| | - Antti Lehtimäki
- Department of Radiology, Kuopio University Hospital, Kuopio, Finland
| | - Jyrki Tervaniemi
- Department of Radiology, Kuopio University Hospital, Kuopio, Finland
| | - Heikki Löppönen
- University of Eastern Finland School of Medicine, Kuopio, Finland
| | - Aarno Dietz
- Department of Otorhinolaryngology - Head and Neck Surgery, Kuopio University Hospital, Kuopio, Finland
| |
Collapse
|
25
|
Mamelle E, Granger B, Sterkers O, Lahlou G, Ferrary E, Nguyen Y, Mosnier I. Long-term residual hearing in cochlear implanted adult patients who were candidates for electro-acoustic stimulation. Eur Arch Otorhinolaryngol 2019; 277:705-713. [PMID: 31802226 DOI: 10.1007/s00405-019-05745-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Accepted: 11/27/2019] [Indexed: 11/27/2022]
Abstract
PURPOSE To evaluate the long-term hearing outcomes in cochlear implanted adults with residual hearing at low frequencies, and the proportion of patients using electro-acoustic stimulation (EAS). METHODS A monocentric retrospective cohort study was performed in a tertiary referral center. Population demographics, surgical approach, pre- and postoperative hearing at low frequencies, in the implanted and contralateral ear, were recorded as well as duration of EAS use. The percentage hearing preservation was calculated according to the formula S (HEARRING group). RESULTS In total, 63 adults (81 ears) with residual hearing underwent cochlear implantation with intent to use EAS processors. Six different types of electrode array were implanted. The mean pure tone audiometry (PTA) shift after cochlear implantation was 16 ± 15 dB HL (range 0-59 dB HL). Half of the implanted ears had minimal hearing preservation or total hearing loss (HL) at 5.5 years and the cumulative risk of total HL was 50% at 7 years. During the follow-up, total HL occurred in 22 ears. The decrease in hearing levels was similar in both implanted and contralateral ear during follow-up (ns, F = 2.46 ± 3, Linear Mixed Model (LMM)). Only 44 patients found a benefit from EAS at the first fitting. At the last visit, EAS processors were fitted in 30% of the cases. The pre- and postoperative mean PTA thresholds were not predictive of EAS use (Cox's proportional hazards analysis). CONCLUSIONS Postoperative residual hearing was observed in 93% of implanted ears, but only half of them had an initial benefit from EAS. No predictive factors were found to influence the use of EAS processors.
Collapse
Affiliation(s)
- Elisabeth Mamelle
- Sorbonne Université, Inserm, Réhabilitation chirurgicale mini-invasive et robotisée de l'audition, Paris, France.
- Otolaryngology Department, Otology, Auditory Implants and Skull Base Surgery Unit, AP-HP, Groupe Hospitalier Pitié-Salpêtrière, Bâtiment Paul Castaigne, 50-52 boulevard Vincent Auriol, 75013, Paris, France.
| | - Benjamin Granger
- Public Health Department, AP-HP, GH Pitié-Salpêtrière, Paris, France
| | - Olivier Sterkers
- Sorbonne Université, Inserm, Réhabilitation chirurgicale mini-invasive et robotisée de l'audition, Paris, France
- Otolaryngology Department, Otology, Auditory Implants and Skull Base Surgery Unit, AP-HP, Groupe Hospitalier Pitié-Salpêtrière, Bâtiment Paul Castaigne, 50-52 boulevard Vincent Auriol, 75013, Paris, France
| | - Ghizlene Lahlou
- Sorbonne Université, Inserm, Réhabilitation chirurgicale mini-invasive et robotisée de l'audition, Paris, France
- Otolaryngology Department, Otology, Auditory Implants and Skull Base Surgery Unit, AP-HP, Groupe Hospitalier Pitié-Salpêtrière, Bâtiment Paul Castaigne, 50-52 boulevard Vincent Auriol, 75013, Paris, France
| | - Evelyne Ferrary
- Sorbonne Université, Inserm, Réhabilitation chirurgicale mini-invasive et robotisée de l'audition, Paris, France
- Otolaryngology Department, Otology, Auditory Implants and Skull Base Surgery Unit, AP-HP, Groupe Hospitalier Pitié-Salpêtrière, Bâtiment Paul Castaigne, 50-52 boulevard Vincent Auriol, 75013, Paris, France
| | - Yann Nguyen
- Sorbonne Université, Inserm, Réhabilitation chirurgicale mini-invasive et robotisée de l'audition, Paris, France
- Otolaryngology Department, Otology, Auditory Implants and Skull Base Surgery Unit, AP-HP, Groupe Hospitalier Pitié-Salpêtrière, Bâtiment Paul Castaigne, 50-52 boulevard Vincent Auriol, 75013, Paris, France
| | - Isabelle Mosnier
- Sorbonne Université, Inserm, Réhabilitation chirurgicale mini-invasive et robotisée de l'audition, Paris, France
- Otolaryngology Department, Otology, Auditory Implants and Skull Base Surgery Unit, AP-HP, Groupe Hospitalier Pitié-Salpêtrière, Bâtiment Paul Castaigne, 50-52 boulevard Vincent Auriol, 75013, Paris, France
| |
Collapse
|
26
|
Iso-Mustajärvi M, Sipari S, Löppönen H, Dietz A. Preservation of residual hearing after cochlear implant surgery with slim modiolar electrode. Eur Arch Otorhinolaryngol 2019; 277:367-375. [PMID: 31673779 PMCID: PMC6981311 DOI: 10.1007/s00405-019-05708-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Accepted: 10/22/2019] [Indexed: 11/15/2022]
Abstract
Purpose To evaluate the insertion results and hearing preservation of a novel slim modiolar electrode (SME) in patients with residual hearing. Methods We retrospectively collected the data from the medical files of 17 patients (18 ears) implanted with a SME. All patients had functional low frequency hearing (PTA (0.125–0.5 kHz) ≤ 80 dB HL). The insertion results were re-examined from the postoperative cone-beam computed tomography scans. Postoperative thresholds were obtained at the time of switch-on of the sound processors (mean 43 days) and at latest follow-up (mean 582 days). The speech recognition in noise was measured with the Finnish matrix sentence test preoperatively and at follow-up. Results The mean insertion depth angle (IDA) was 395°. Neither scala dislocations nor tip fold over were detected. There were no total hearing losses. Functional low-frequency hearing was preserved in 15/18 (83%) ears at switch-on and in 14/17 (82%) ears at follow-up. According to HEARRING classification, 55% (10/18) had complete HP at switch-on and 41% (7/17) still at follow-up. Thirteen patients (14 ears) were initially fitted with electric–acoustic stimulation and seven patients (8 ears) continued to use it after follow-up. Conclusions The preliminary hearing preservation results with the SME were more favorable than reported for other perimodiolar electrodes. The results show that the array may also be feasible for electro-acoustic stimulation; it is beneficial in that it provides adequate cochlear coverage for pure electrical stimulation in the event of postoperative or progressive hearing loss.
Collapse
Affiliation(s)
- Matti Iso-Mustajärvi
- University of Eastern Finland, Yliopistonranta 1, 70210, Kuopio, Finland. .,Kuopio University Hospital, Ear, Nose and Throat Diseases, KNK-klinikka, Puijonlaaksontie 2, 70210, Kuopio, Finland.
| | - Sini Sipari
- University of Eastern Finland, Yliopistonranta 1, 70210, Kuopio, Finland.,Kuopio University Hospital, Ear, Nose and Throat Diseases, KNK-klinikka, Puijonlaaksontie 2, 70210, Kuopio, Finland
| | - Heikki Löppönen
- University of Eastern Finland, Yliopistonranta 1, 70210, Kuopio, Finland.,Kuopio University Hospital, Ear, Nose and Throat Diseases, KNK-klinikka, Puijonlaaksontie 2, 70210, Kuopio, Finland
| | - Aarno Dietz
- University of Eastern Finland, Yliopistonranta 1, 70210, Kuopio, Finland
| |
Collapse
|
27
|
Heutink F, Verbist BM, Mens LHM, Huinck WJ, Mylanus EAM. The evaluation of a slim perimodiolar electrode: surgical technique in relation to intracochlear position and cochlear implant outcomes. Eur Arch Otorhinolaryngol 2019; 277:343-350. [PMID: 31650350 PMCID: PMC6981103 DOI: 10.1007/s00405-019-05696-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 10/11/2019] [Indexed: 11/29/2022]
Abstract
Purpose In cochlear implantation (CI), the two factors that are determined by the surgeon with a potential significant impact on the position of the electrode within the cochlea and the potential outcome, are the surgical technique and electrode type. The objective of this prospective study was to evaluate the position of the slim, perimodiolar electrode (SPE), and to study the influence of the SPE position on CI outcome. Methods Twenty-three consecutively implanted, adult SPE candidates were included in this prospective cohort study conducted between December 2016 and April 2019. Mean age at surgery was 59.5 years. Mean preoperative residual hearing was 92.2 dB. Intra-operative fluoroscopy and high-resolution computed tomography scans were performed to evaluate electrode position after insertion using a cochleostomy (CS) approach. Follow-up was 12 months after implantation; residual hearing (6–8 weeks) and speech perception (6–8 weeks and 12 months) were evaluated in relation to the intracochlear SPE position. Results In most patients in whom the SPE was positioned in the scala tympani residual hearing was preserved [mean absolute increase in PTA of 4.4 dB and 77.2% relative hearing preservation (RHP%)]. Translocation into the scala vestibuli occurred in 36% of the insertions, resulting in a mean absolute increase in PTA of 17.9 dB, and a RHP% of 19.2%. Participants with a translocation had poorer speech perception scores at 12-month follow-up. Conclusion Given the incidence of CS-associated translocations with the SPE and the negative effect on outcome, it is advised to insert the SPE using the (extended) round window approach.
Collapse
Affiliation(s)
- Floris Heutink
- Department of Otorhinolaryngology, Radboudumc, Route 377, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands. .,Donders Institute for Brain, Cognition and Behaviour, Radboudumc, Route 780, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.
| | - Berit M Verbist
- Department of Radiology, Radboudumc, Nijmegen, The Netherlands
| | - Lucas H M Mens
- Department of Otorhinolaryngology, Radboudumc, Route 377, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.,Donders Institute for Brain, Cognition and Behaviour, Radboudumc, Route 780, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Wendy J Huinck
- Department of Otorhinolaryngology, Radboudumc, Route 377, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.,Donders Institute for Brain, Cognition and Behaviour, Radboudumc, Route 780, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Emmanuel A M Mylanus
- Department of Otorhinolaryngology, Radboudumc, Route 377, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.,Donders Institute for Brain, Cognition and Behaviour, Radboudumc, Route 780, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
| |
Collapse
|
28
|
Al Omari A, Nuseir A, Ata MB, Khasawneh L, Alhowary AA, Alzoubi F. Accuracy of intraoperative electrophysiological testing in confirming correct cochlear implant electrode positions. Cochlear Implants Int 2019; 20:324-330. [PMID: 31464178 DOI: 10.1080/14670100.2019.1656904] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Objective: To investigate the accuracy of intraoperative electrophysiological studies in detecting incorrectly positioned electrodes in cochlear implant surgery. Study design: A retrospective chart review. Setting: Tertiary referral centre. Patients: In total, 104 consecutive patients with a mean age of 5 years underwent cochlear implant surgery at our centre between January 2012 and December 2013. All patients were implanted with Cochlear Nucleus Freedom implants. Method: A retrospective study to compare intraoperative neural response telemetry (NRT), impedance and electrode position using Stenver's transorbital plain X-ray view. Results: Intraoperative electrophysiological tests for patients with Cochlear Nucleus Freedom implants showed 97% sensitivity and 100% specificity compared with postoperative X-ray imaging. Conclusion: NRT results for the position of cochlear implants were very accurate when checked by X-ray imaging showing that this technique is sufficient in most cases. Stenver's plain X-ray view is needed in complicated cases with abnormal NRT testing or difficult electrode insertion.
Collapse
Affiliation(s)
- Ahmad Al Omari
- Otolaryngology Department, Faculty of Medicine, Jordan University of Science and Technology , P.O Box 3030, Irbid 22110 , Jordan
| | - Amjad Nuseir
- Otolaryngology Department, Faculty of Medicine, Jordan University of Science and Technology , P.O Box 3030, Irbid 22110 , Jordan
| | - Majid Bani Ata
- Otolaryngology Department, Faculty of Medicine, Jordan University of Science and Technology , P.O Box 3030, Irbid 22110 , Jordan
| | - Laith Khasawneh
- Otolaryngology Department, Faculty of Medicine, Hashemite University , P.O Box 3030127, Zarqa , Jordan
| | - Ala A Alhowary
- Department of Anesthesiology, Faculty of Medicine, Jordan University of Science and Technology , P.O Box 3030, Irbid 22110 , Jordan
| | - Firas Alzoubi
- Otolaryngology Department, Faculty of Medicine, Jordan University of Science and Technology , P.O Box 3030, Irbid 22110 , Jordan
| |
Collapse
|
29
|
Cuda D, Murri A. Assessment of cochlear trauma and telemetry measures after cochlear implantation: A comparative study between Nucleus ® CI512 and CI532 electrode arrays. Audiol Res 2019; 9:223. [PMID: 31402972 PMCID: PMC6646859 DOI: 10.4081/audiores.2019.223] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Accepted: 06/08/2019] [Indexed: 11/22/2022] Open
Abstract
The aim of this study was to compare the new Cochlear™ Nucleus® Profile with Slim Modiolar Electrode (CI532, Cochlear Ltd., Sidney, Australia) with the previous Contour Advance® (CI512) implant through postoperative residual hearing (RH) threshold shift and telemetry measurements as indirect measures of cochlear trauma. We compared 21 patients implanted with the CI532 and 20 patients implanted with the CI512, matching the 2 groups for age and for hearing loss etiology. All subjects received audiological pure tone average (PTA) calculation pre- and postimplant. Electrode impedance was measured, followed by AutoNRT® to measure and evaluate the Neural Response Telemetry (NRT®) thresholds. Telemetry recordings were made intraoperatively, one month after surgery and one month after activation. The NRT-Ratio was calculated to evaluate full scala tympani (ST) insertion. The results showed a higher number of patients with preserved measurable hearing with the CI532 (10/15; P>0.05) compared to the CI512 (5/14; P<0.05). A significant difference in post-operative low frequency PTA was observed between the two groups. There were no significant differences for telemetry measurements and NRTRatio evaluation of full ST insertion (CI512: 81%; CI532: 95%). A significantly higher number of patients who preserved measurable hearing with the CI532, and a significantly higher post-operative low frequency PTA threshold compared with the CI512 confirmed better RH preservation and lower apical cochlear damage with the CI532. There was a high number of full ST insertions for both electrode arrays. Future studies should investigate the audiological effect of implantation in patients with higher levels of RH, correlating the results with the scalar position, to assess any lesser trauma of the CI532.
Collapse
Affiliation(s)
- Domenico Cuda
- Department of Otorhinolaryngology, Guglielmo da Saliceto Hospital, Piacenza, Italy
| | - Alessandra Murri
- Department of Otorhinolaryngology, Guglielmo da Saliceto Hospital, Piacenza, Italy
| |
Collapse
|
30
|
Gomez Serrano M, Patel S, Harris R, Selvadurai D. Initial surgical and clinical experience with the Nucleus CI532 slim modiolar electrode in the UK. Cochlear Implants Int 2019; 20:207-216. [PMID: 30947632 DOI: 10.1080/14670100.2019.1597461] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
OBJECTIVE The goal of this work is to describe the first experience in the UK with the slim pre-curved perimodiolar electrode Nucleus CI532 in a continuous series of patients in terms of surgical and clinical reliability and early performance outcomes. METHOD In this retrospective review we describe the complication rate (including electrode array tip fold-over), NRT thresholds, hearing preservation, power efficiency and CI performance outcomes in a continuous series of 40 cochlear implants CI532 performed between October 2016 and November 2017 in 17 adults and 13 children with severe to profound hearing loss. RESULTS Preliminary data from these groups reveals some low-frequency hearing preservation in the CI532 group although none of the patients were conventional hearing preservation candidates. NRT thresholds, power efficiency, and BKB sentences in quiet were measured at 3 and 6 months post activation. There were no significant differences in these results. The average BKB score in quiet increases from 22% pre-operatively to 58% at 3 months and 70% at 6 months. In addition, although hearing preservation was not an objective, low-frequency thresholds were preserved in 20% of cases at 3 and 6 months post-operatively. Complications were observed in 5 cases, one case with non-device related aerocoele and four related to the device array: two cases of tip roll over, one case of the electrode array being placed extra-cochlea, and one case with the electrode buckling into the middle ear. The last 2 cases were dealt with per-operatively. DISCUSSION Our preliminary results with the CI532 implant indicate that it may be reliably placed with standard surgical techniques but care is needed during the deployment of the electrode. Further initial data suggest that switch on and early electrophysiological measures are comparable to the existing CI 512 device. However whilst preliminary, our data suggest that it may be possible to use this electrode for hearing preservation. However, further studies are required to determine its definitive advantage over other electrode designs. CONCLUSION CI532 is a reliable device offering good initial results and could be an option for hearing preservation although further studies are required.
Collapse
Affiliation(s)
- Manuel Gomez Serrano
- a St George's Auditory Implant Service, St Georges NHS Foundation Trust London , London , UK
| | - Sharmila Patel
- a St George's Auditory Implant Service, St Georges NHS Foundation Trust London , London , UK
| | - Robert Harris
- a St George's Auditory Implant Service, St Georges NHS Foundation Trust London , London , UK
| | - David Selvadurai
- a St George's Auditory Implant Service, St Georges NHS Foundation Trust London , London , UK
| |
Collapse
|
31
|
|
32
|
Dhanasingh A, Jolly C. Review on cochlear implant electrode array tip fold-over and scalar deviation. J Otol 2019; 14:94-100. [PMID: 31467506 PMCID: PMC6712287 DOI: 10.1016/j.joto.2019.01.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 12/20/2018] [Accepted: 01/07/2019] [Indexed: 11/26/2022] Open
Abstract
Objective Determine the occurrence rate of cochlear implant (CI) electrode tip fold-over and electrode scalar deviation as reported in patient cases with different commercial electrode types. Data-sources PubMed search for identifying peer-reviewed articles published till 2018 on CI electrode tip fold-over and scalar deviation. Key-words for searching were “Cochlear electrode tip fold-over”, “Cochlear electrode scalar position” and “Cochlear electrode scalar location”. Articles-selection Only if electrode related issues were investigated in patient cases. 38 articles met the inclusion-criteria. Results 13 articles on electrode tip fold-over issue covering 3177 implanted ears, out of which 50 ears were identified with electrode tip fold-over with an occurrence rate of 1.57%. Out of 50 ears, 43 were implanted with pre-curved electrodes and the remaining 7 with lateral-wall electrodes. One article reported on both tip fold-over and scalar deviation. 26 articles reported on the electrode scalar deviation covering an overall number of 2046 ears out of which, 458 were identified with electrode scalar deviation at a rate of 22.38%. After removing the studies that did not report on the number of electrodes per electrode type, it was 1324 ears implanted with pre-curved electrode and 507 ears with lateral-wall electrode. Out of 1324 pre-curved electrode implanted ears, 424 were reported with scalar deviation making an occurrence rate of 32%. Out of 507 lateral-wall electrode implanted ears, 43 were associated with scalar deviation at an occurrence rate of 6.7%. Conclusion This literature review revealing the fact of higher rate of electrode insertion trauma associated with pre-curved electrode type irrespective of CI brand is one step closer to obsolete it from the clinical practice in the interest of patient's cochlear health.
Collapse
Affiliation(s)
| | - Claude Jolly
- MED-EL Medical Electronics GmbH, Innsbruck, Austria
| |
Collapse
|
33
|
Dhanasingh A. Why Pre-Curved Modiolar Hugging Electrodes Only Cover The Basal Turn of The Cochlea and Not Beyond that? J Int Adv Otol 2018; 14:376-381. [PMID: 30644378 PMCID: PMC6354519 DOI: 10.5152/iao.2018.5831] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2018] [Revised: 09/14/2018] [Accepted: 09/14/2018] [Indexed: 11/22/2022] Open
Abstract
The question of why pre-curved modiolar hugging (MH) electrodes only cover the basal turn of the cochlea and not beyond that is unanswered yet in the CI field. Therefore the aim of this article is to show what the practical limitations are with the pre-curved MH electrode design in not being able to fabricate beyond one full turn. Every CI electrode design needs a metal mold with grooves for placing the platinum wires and for injecting with the silicone elastomer. Limitations in making a mold with groove that goes beyond one full turn of curvature along with the mechanical deformation of the curved silicone elastomer, prevents making a pre-curved MH electrode beyond one full turn. Electrode tip fold-over, electrode scalar deviation and the inconsistent electrode to modiolus wall proximity are the reported issues with this electrode type which does not help by any means to the operating surgeon and the pediatric candidates especially. If intra-operative imaging is recommended to confirm the proper placement of the electrode for one particular electrode design, then how many clinics in the world may have this facility and is it ethical to put the patient under more radiation risk are the natural questions that needs to be answered in the interest of the patient. Every CI brand should come out of their marketing philosophy and innovate what is essential in bringing the full benefit of the device to the patients.
Collapse
|
34
|
Risi F. Considerations and Rationale for Cochlear Implant Electrode Design - Past, Present and Future. J Int Adv Otol 2018; 14:382-391. [PMID: 30644379 PMCID: PMC6354527 DOI: 10.5152/iao.2018.6372] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Accepted: 12/17/2018] [Indexed: 12/16/2022] Open
Abstract
The electrode array of a cochlear implant forms a permanent, often lifelong interface between the implanted electronics and neural structures of the cochlea. A cochlear implant is primarily prescribed to restore hearing via electrical stimulation of the auditory nerve. As with any neural stimulator intended to either deliver electrical stimulus or record a neural response, the aim is to place the electrodes in close proximity to the target neural structures. The broadening of indications and the concept of preservation of low-frequency residual hearing over the last two decades has resulted in an increased understanding of the mechanisms and implications of intracochlear trauma for both the hearing preservation surgery and electrical stimulation outcomes with cochlear implantation, as well as the influence of many biographic and audiological patient factors correlated with achieving better hearing outcomes. These two goals, the proximity to the cochlear nerve for electrical stimulation and the preservation of cochlear structures, have typically been viewed as mutually exclusive, with perimodiolar electrode arrays being preferred for the former, and lateral wall electrode arrays for the latter. The design evolution of both the lateral wall and perimodiolar electrodes is presented, considering the cochlea anatomy and continued understanding of the mechanics and dynamics of electrode insertion, along with the influence of the ongoing changes to the intracochlear environment to provide a rationale for the electrode design with the intent to provide the greatest patient benefit over their implanted lifetime.
Collapse
Affiliation(s)
- Frank Risi
- Group Product Manager, Surgical - Implants, Cochlear Limited, New South Wales, Australia
| |
Collapse
|
35
|
Scalar localisation of peri-modiolar electrodes and speech perception outcomes. The Journal of Laryngology & Otology 2018; 132:1000-1006. [PMID: 30370884 DOI: 10.1017/s0022215118001871] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE To identify the intracochlear electrode position in cochlear implant recipients and determine the correlation to speech perception for two peri-modiolar electrode arrays. METHODS Post-operative cone-beam computed tomography images of 92 adult recipients of the 'CI512' electrode and 18 adult recipients of the 'CI532' electrode were analysed. Phonemes scores were recorded pre-implantation, and at 3 and 12 months post-implantation. RESULTS All CI532 electrodes were wholly within scala tympani. Of the 79 CI512 electrodes intended to be in scala tympani, 58 (73 per cent) were in scala tympani, 14 (17 per cent) were translocated and 7 (9 per cent) were wholly in scala vestibuli. Thirteen CI512 electrodes were deliberately inserted into scala vestibuli. Speech perception scores for post-lingual recipients were higher in the scala tympani group (69.1 per cent) compared with the scala vestibuli (54.2 per cent) and translocation (50 per cent) groups (p < 0.05). Electrode location outside of scala tympani independently resulted in a 10.5 per cent decrease in phoneme scores. CONCLUSION Cone-beam computed tomography was valuable for demonstrating electrode position. The rate of scala tympani insertion was higher in CI532 than in CI512 electrodes. Scala vestibuli insertion and translocation were associated with poorer speech perception outcomes.
Collapse
|
36
|
Investigation of ultra-low insertion speeds in an inelastic artificial cochlear model using custom-made cochlear implant electrodes. Eur Arch Otorhinolaryngol 2018; 275:2947-2956. [DOI: 10.1007/s00405-018-5159-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Accepted: 10/04/2018] [Indexed: 10/28/2022]
|
37
|
Abstract
OBJECTIVE To describe outcomes from cochlear implantation with a new, slim modiolar electrode array. STUDY DESIGN Retrospective cohort study. SETTING Tertiary referral centers. PATIENTS Adult cochlear implant candidates. INTERVENTIONS Cochlear implantation with CI532 (Cochlear Corp). MAIN OUTCOME MEASURES Pre- and postoperative speech perception scores, operative details, and postoperative computed tomography (CT) reconstructions of array location. RESULTS One hundred seventeen patients are implanted to date. There were eight tip rollovers identified with intraoperative x-ray and resolved with reinsertion. An additional rollover was identified on postoperative CT. CT reconstructions in 17 of 23 patients showed complete scala tympani placement with a wrap factor of 58% (range 53-64%) and a mean insertion angle of 406 degrees (range 360-452 degrees). Three implants demonstrated array translocation with electrodes in the scala vestibuli. Consonant-nucleus-consonant word scores improved from 10% preoperatively to 48% at 3 months postoperatively. Pure-tone thresholds were preserved postoperatively in 37 to 52% of patients across frequencies from 250 to 4000 Hz. Functional pure-tone thresholds (≤80 dB) were recorded in 9 to 25% of patients. CONCLUSION CI532 array insertion results in consistent scala tympani location and provides expected audiologic performance. Initial hearing preservation results are not consistent with current electro-acoustic arrays.
Collapse
|
38
|
Menegatti Pavan AL, Alves AFF, Giacomini G, Altemani JMC, Castilho AM, Lauria RA, da Silva VAR, Guimarães AC, de Pina DR. Cochlear implants: Insertion assessment by computed tomography. Am J Otolaryngol 2018; 39:431-435. [PMID: 29685378 DOI: 10.1016/j.amjoto.2018.04.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 04/10/2018] [Accepted: 04/14/2018] [Indexed: 11/17/2022]
Abstract
BACKGROUND AND OBJECTIVES Imaging exams play a key role in cochlear implants with regard to both planning implantation before surgery and quality control after surgery. The ability to visualize the three-dimensional location of implanted electrodes is useful in clinical routines for assessing patient outcome. The aim of this study was to evaluate linear and angular insertion depth measurements of cochlear implants based on conventional computed tomography. METHODS Tools for linear and angular measurements of cochlear implants were used in computed tomography exams. The tools realized the insertion measurements in an image reconstruction of the CIs, based on image processing techniques. We comprehensively characterized two cochlear implant models while obviating possible changes that can be caused by different cochlea sizes by using the same human temporal bones to evaluate the implant models. RESULTS The tools used herein were able to differentiate the insertion measurements between two cochlear implant models widely used in clinical practice. We observed significant differences between both insertion measurements because of their different design and construction characteristics (p = 0.004 and 0.003 for linear and angular measurements, respectively; t-test). The presented methodology showed to be a good tool to calculate insertion depth measurements, since it is easy to perform, produces high-resolution images, and is able to depict all the landmarks, thus enabling measurement of the angular and linear insertion depth of the most apical electrode contacts. CONCLUSION The present study demonstrates practical and useful tools for evaluating cochlear implant electrodes in clinical practice. Further studies should measure preoperative and postoperative benefits in terms of speech recognition and evaluate the preservation of residual hearing in the implanted ear. Such studies can also determine correlations between surgical factors, electrode positions, and performance. In addition to refined surgical techniques, the precise evaluation of cochlear length and correct choice of cochlear implant characteristics can play an important role in postoperative outcomes.
Collapse
Affiliation(s)
- Ana Luiza Menegatti Pavan
- Instituto de Biociências de Botucatu, Universidade Estadual Paulista (IBB-UNESP), Botucatu, São Paulo, Brazil
| | - Allan Felipe Fattori Alves
- Instituto de Biociências de Botucatu, Universidade Estadual Paulista (IBB-UNESP), Botucatu, São Paulo, Brazil
| | - Guilherme Giacomini
- Instituto de Biociências de Botucatu, Universidade Estadual Paulista (IBB-UNESP), Botucatu, São Paulo, Brazil
| | | | - Arthur Menino Castilho
- Hospital de Clínicas, Universidade Estadual de Campinas (HC-UNICAMP), Campinas, São Paulo, Brazil
| | - Raquel Andrade Lauria
- Hospital de Clínicas, Universidade Estadual de Campinas (HC-UNICAMP), Campinas, São Paulo, Brazil
| | | | | | - Diana Rodrigues de Pina
- Faculdade de Medicina de Botucatu, Universidade Estadual Paulista (FMB-UNESP), Botucatu, São Paulo, Brazil.
| |
Collapse
|
39
|
A New Slim Modiolar Electrode Array for Cochlear Implantation: A Radiological and Histological Study. Otol Neurotol 2018; 38:e327-e334. [PMID: 28796083 DOI: 10.1097/mao.0000000000001542] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
HYPOTHESIS To explore the results of a new slim modiolar electrode array (SMA) with respect to intracochlear placement and trauma evaluated by detailed radiologic imaging and histology. BACKGROUND Hearing and structure preservation is the goal of cochlear implantation for advanced hearing outcomes. Currently, this is most consistently achieved with thin lateral wall electrodes. Modiolar electrodes are located nearer the modiolus and may provide some electrophysiological advantages, but have a greater tendency for causing insertion trauma. METHODS The SMA was implanted in 20 fresh-frozen human temporal bones (TB). All TBs were scanned pre- and postoperatively with cone beam computed tomography. For atraumatic insertion, the round window approach was preferred. Scalar localization and trauma were analyzed by three-dimensional image fusion reconstructions of the pre- and postimplant scans. The TBs underwent histologic examination to validate the radiologic findings. RESULTS Insertion through the round window was performed in 19 TBs and through a cochleostomy in one TB. In one TB trauma in the form of scala translocation was identified radiologically and histologically. In the remaining TBs there was no insertion trauma. Adequate modiolar localization of the SMA was found in 19 of 20 TBs. The mean angular insertion depth was 400 degrees without correlation to cochlea size. There was no significant statistical difference between the radiological and histological measurements of electrode localization. CONCLUSION The SMA showed consistent and atraumatic insertion results in TBs. Pre- and postimplant cone beam computed tomography with image fusion was shown to be very accurate for the assessment of electrode position and insertion trauma.
Collapse
|
40
|
Dhanasingh A, Jolly C. An overview of cochlear implant electrode array designs. Hear Res 2017; 356:93-103. [DOI: 10.1016/j.heares.2017.10.005] [Citation(s) in RCA: 152] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 07/26/2017] [Accepted: 10/13/2017] [Indexed: 11/28/2022]
|
41
|
Trakimas DR, Kozin ED, Ghanad I, Barber SR, Curtin H, Remenschneider AK. Precurved Cochlear Implants and Tip Foldover: A Cadaveric Imaging Study. Otolaryngol Head Neck Surg 2017; 158:343-349. [PMID: 29086634 DOI: 10.1177/0194599817738978] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objective This study aims to define a reliable protocol for radiographic identification of placement and tip foldover of newly designed precurved and straight electrodes. Study Design Prospective imaging study. Setting Academic institution. Methods Three models of cochlear implants (Cochlear, MED-EL, and Advanced Bionics) were inserted into fresh cadaveric specimens (n = 2) in 3 configurations (normal positioning in the scala tympani, intracochlear tip foldover, and placement into the vestibular system) for a total of 9 implant scenarios. Specimens were imaged with plain radiography in Stenvers projection, as well as by high-resolution computed tomography. Results Electrode placement and presence or absence of electrode tip foldover were easily identified in all 9 scenarios on plain radiography based on the described technique. Each was confirmed with high-resolution computed tomography. Plain film temporal bone images of new electrode designs with proper and improper placement are provided for reference. Conclusion A defined protocol for intraoperative plain film radiography allowed for reliable imaging of 3 newly designed cochlear implant electrodes and immediate identification of extracochlear placement and tip foldover. Findings may be used for intraoperative confirmation of electrode array placement.
Collapse
Affiliation(s)
- Danielle R Trakimas
- 1 Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, USA.,2 Department of Otolaryngology, Harvard Medical School, Boston, Massachusetts, USA.,3 University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Elliott D Kozin
- 1 Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, USA.,2 Department of Otolaryngology, Harvard Medical School, Boston, Massachusetts, USA
| | - Iman Ghanad
- 1 Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, USA.,2 Department of Otolaryngology, Harvard Medical School, Boston, Massachusetts, USA
| | - Sam R Barber
- 1 Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, USA.,2 Department of Otolaryngology, Harvard Medical School, Boston, Massachusetts, USA
| | - Hugh Curtin
- 4 Department of Radiology, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, USA
| | - Aaron K Remenschneider
- 1 Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, USA.,2 Department of Otolaryngology, Harvard Medical School, Boston, Massachusetts, USA.,5 Department of Otolaryngology, UMass Memorial Medical Center, Worcester, Massachusetts, USA
| |
Collapse
|
42
|
Aschendorff A, Briggs R, Brademann G, Helbig S, Hornung J, Lenarz T, Marx M, Ramos A, Stöver T, Escudé B, James CJ. Clinical investigation of the Nucleus Slim Modiolar Electrode. Audiol Neurootol 2017; 22:169-179. [PMID: 29059669 DOI: 10.1159/000480345] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 08/11/2017] [Indexed: 11/19/2022] Open
Abstract
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.
Collapse
|
43
|
Cuda D, Murri A. Cochlear implantation with the nucleus slim modiolar electrode (CI532): a preliminary experience. Eur Arch Otorhinolaryngol 2017; 274:4141-4148. [DOI: 10.1007/s00405-017-4774-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 10/11/2017] [Indexed: 10/18/2022]
|
44
|
Abstract
Here I identify two gaps in cochlear implants that have been limiting their performance and acceptance. First, cochlear implant performance has remained largely unchanged, despite the number of publications tripling per decade in the last 30 years. Little has been done so far to address a fundamental limitation in the electrode-to-neuron interface, with the electrode size being a thousand times larger than the neuron diameter while the number of electrodes being a thousand times less. Both the small number and the large size of electrodes produce broad spatial activation and poor frequency resolution that limit current cochlear implant performance. Second, a similarly rapid growth in cochlear implant volume has not produced an expected decrease in unit price in the same period. The high cost contributes to low market penetration rate, which is about 20% in developed countries and less than 1% in developing countries. I will discuss changes needed in both research strategy and business practice to close the gap between prosthetic and normal hearing as well as that between haves and have-nots.
Collapse
|
45
|
Insertion forces and intracochlear trauma in temporal bone specimens implanted with a straight atraumatic electrode array. Eur Arch Otorhinolaryngol 2017; 274:2131-2140. [PMID: 28238160 DOI: 10.1007/s00405-017-4485-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 01/25/2017] [Indexed: 10/20/2022]
Abstract
The aim of the study was to evaluate insertion forces during manual insertion of a straight atraumatic electrode in human temporal bones, and post-implantation histologic evaluation of the samples to determine whether violation of intracochlear structures is related to insertion forces. In order to minimize intracochlear trauma and preserve residual hearing during cochlear implantation, knowledge of the insertion forces is necessary. Ten fresh frozen human temporal bones were prepared with canal wall down mastoidectomy. All samples were mounted on a one-axis force sensor. Insertion of a 16-mm straight atraumatic electrode was performed from different angles to induce "traumatic" insertion. Histologic evaluation was performed in order to evaluate intracochlear trauma. In 4 of 10 samples, dislocation of the electrode into scala vestibuli was observed. The mean insertion force for all 10 procedures was 0.003 ± 0.005 N. Insertion forces measured around the site of dislocation to scala vestibuli in 3 of 4 samples were significantly higher than insertion forces at the same location of the cochleae measured in samples without trauma (p < 0.04). Mean force during the whole insertion process of the straight atraumatic electrode is lower than reported by other studies using longer electrodes. Based on our study, insertion forces leading to basilar membrane trauma may be lower than the previously reported direct rupture forces.
Collapse
|
46
|
Copson B, Wijewickrema S, Zhou Y, Piromchai P, Briggs R, Bailey J, Kennedy G, O'Leary S. Supporting skill acquisition in cochlear implant surgery through virtual reality simulation. Cochlear Implants Int 2017; 18:89-96. [DOI: 10.1080/14670100.2017.1289299] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Bridget Copson
- Department of Surgery (Otolaryngology), University of Melbourne, Australia
| | | | - Yun Zhou
- Department of Surgery (Otolaryngology), University of Melbourne, Australia
| | - Patorn Piromchai
- Department of Surgery (Otolaryngology), University of Melbourne, Australia
- Department of Otorhinolaryngology, Khon Kaen University, Thailand
| | - Robert Briggs
- Department of Surgery (Otolaryngology), University of Melbourne, Australia
| | - James Bailey
- Department of Computing and Information Systems, University of Melbourne, Australia
| | - Gregor Kennedy
- Melbourne Centre for the Study of Higher Education, University of Melbourne, Australia
| | - Stephen O'Leary
- Department of Surgery (Otolaryngology), University of Melbourne, Australia
| |
Collapse
|
47
|
Three-Dimensional Force Profile During Cochlear Implantation Depends on Individual Geometry and Insertion Trauma. Ear Hear 2017; 38:e168-e179. [DOI: 10.1097/aud.0000000000000394] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
|
48
|
Damage to inner ear structure during cochlear implantation: Correlation between insertion force and radio-histological findings in temporal bone specimens. Hear Res 2016; 344:90-97. [PMID: 27825860 DOI: 10.1016/j.heares.2016.11.002] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2016] [Revised: 10/13/2016] [Accepted: 11/03/2016] [Indexed: 11/23/2022]
Abstract
Cochlear implant insertion should be as least traumatic as possible in order to reduce trauma to the cochlear sensory structures. The force applied to the cochlea during array insertion should be controlled to limit insertion-related damage. The relationship between insertion force and histological traumatism remains to be demonstrated. Twelve freshly frozen cadaveric temporal bones were implanted with a long straight electrodes array through an anterior extended round window insertion using a motorized insertion tool with real-time measurement of the insertion force. Anatomical parameters, measured on a pre-implantation cone beam CT scan, position of the array and force metrics were correlated with post-implantation scanning electron microscopy images and histological damage assessment. An atraumatic insertion occurred in six cochleae, a translocation in five cochleae and a basilar membrane rupture in one cochlea. The translocation always occurred in the 150- to 180-degree region. In the case of traumatic insertion, different force profiles were observed with a more irregular curve arising from the presence of an early peak force (30 ± 18.2 mN). This corresponded approximately to the first point of contact of the array with the lateral wall of the cochlea. Atraumatic and traumatic insertions had significantly different force values at the same depth of insertion (p < 0.001, two-way ANOVA), and significantly different regression lines (y = 1.34x + 0.7 for atraumatic and y = 3.37x + 0.84 for traumatic insertion, p < 0.001, ANCOVA). In the present study, the insertion force was correlated with the intracochlear trauma. The 150- to 180-degree region represented the area at risk for scalar translocation for this straight electrodes array. Insertion force curves with different sets of values were identified for traumatic and atraumatic insertions; these values should be considered during motorized insertion of an implant so as to be able to modify the insertion parameters (e.g axis of insertion) and facilitate preservation of endocochlear structures.
Collapse
|
49
|
Robot-assisted perception augmentation for online detection of insertion failure during cochlear implant surgery. ROBOTICA 2016. [DOI: 10.1017/s0263574716000333] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
SUMMARYDuring the past decade, robotics for cochlear implant electrode array insertion has been limited to manipulation assistance. Going beyond manipulation assistance, this paper presents the new concept of perception augmentation to detect and warn against the onset of intracochlear electrode array tip folding. This online failure detection method uses a combination of intraoperative electrode insertion force data and a predictive model of insertion force profile progression as a function of insertion depth. The predictive model uses statistical characterization of insertion force profiles during normal robotic electrode array insertions as well as the history of intra-operative insertion forces. Online detection of onset of tip folding is achieved using the predictive model as an input into a support vector machine classifier. Results show that the detection of tip folding onset can be achieved with an accuracy of 88% despite the use of intra-operative insertion force data representing incomplete insertion. This result is significant because it allows the surgeon or robot to choose a corrective action for preventing intra-cochlear complications.
Collapse
|
50
|
|