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Smit IH, Parmentier JIM, Rovel T, van Dieen J, Serra Bragança FM. Towards standardisation of surface electromyography measurements in the horse: Bipolar electrode location. J Electromyogr Kinesiol 2024; 76:102884. [PMID: 38593582 DOI: 10.1016/j.jelekin.2024.102884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 03/15/2024] [Accepted: 03/30/2024] [Indexed: 04/11/2024] Open
Abstract
The use of surface electromyography in the field of animal locomotion has increased considerably over the past decade. However, no consensus exists on the methodology for data collection in horses. This study aimed to start the development of recommendations for bipolar electrode locations to collect surface electromyographic data from horses during dynamic tasks. Data were collected from 21 superficial muscles of three horses during trot on a treadmill using linear electrode arrays. The data were assessed both quantitatively (signal-to-noise ratio (SNR) and coefficient of variation (CoV)) and qualitatively (presence of crosstalk and activation patterns) to compare and select electrode locations for each muscle. For most muscles and horses, the highest SNR values were detected near or cranial/proximal to the central region of the muscle. Concerning the CoV, there were larger differences between muscles and horses than within muscles. Qualitatively, crosstalk was suspected to be present in the signals of twelve muscles but not in all locations in the arrays. With this study, a first attempt is made to develop recommendations for bipolar electrode locations for muscle activity measurements during dynamic contractions in horses. The results may help to improve the reliability and reproducibility of study results in equine biomechanics.
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Affiliation(s)
- I H Smit
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584CM Utrecht, the Netherlands.
| | - J I M Parmentier
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584CM Utrecht, the Netherlands; Pervasive Systems Group, Faculty of Electrical Engineering, Mathematics and Computer Science, University of Twente, 7522NB Enschede, the Netherlands
| | - T Rovel
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584CM Utrecht, the Netherlands
| | - J van Dieen
- Department of Human Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, Netherlands
| | - F M Serra Bragança
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584CM Utrecht, the Netherlands; Sleip AI, Birger Jarlsgatan 58, 11426 Stockholm, Sweden
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2
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Ino K, Utagawa Y, Shiku H. Microarray-Based Electrochemical Biosensing. Adv Biochem Eng Biotechnol 2023. [PMID: 37306698 DOI: 10.1007/10_2023_229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Microarrays are widely utilized in bioanalysis. Electrochemical biosensing techniques are often applied in microarray-based assays because of their simplicity, low cost, and high sensitivity. In such systems, the electrodes and sensing elements are arranged in arrays, and the target analytes are detected electrochemically. These sensors can be utilized for high-throughput bioanalysis and the electrochemical imaging of biosamples, including proteins, oligonucleotides, and cells. In this chapter, we summarize recent progress on these topics. We categorize electrochemical biosensing techniques for array detection into four groups: scanning electrochemical microscopy, electrode arrays, electrochemiluminescence, and bipolar electrodes. For each technique, we summarize the key principles and discuss the advantages, disadvantages, and bioanalysis applications. Finally, we present conclusions and perspectives about future directions in this field.
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Affiliation(s)
- Kosuke Ino
- Graduate School of Engineering, Tohoku University, Sendai, Miyagi, Japan.
| | - Yoshinobu Utagawa
- Graduate School of Environmental Studies, Tohoku University, Sendai, Miyagi, Japan
| | - Hitoshi Shiku
- Graduate School of Engineering, Tohoku University, Sendai, Miyagi, Japan.
- Graduate School of Environmental Studies, Tohoku University, Sendai, Miyagi, Japan.
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3
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Ren LJ, Yu Y, Zhang YH, Liu XD, Sun ZJ, Yao WJ, Zhang TY, Wang C, Li CL. Three-dimensional finite element analysis on cochlear implantation electrode insertion. Biomech Model Mechanobiol 2022; 22:467-478. [PMID: 36513945 DOI: 10.1007/s10237-022-01657-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Accepted: 11/19/2022] [Indexed: 12/14/2022]
Abstract
Studying the insertion process of cochlear implant (CI) electrode array (EA) is important to ensure successful, sufficient, and safe implantation. A three-dimensional finite element (FE) model was developed to simulate the insertion process. The cochlear structures were reconstructed from an average statistical shape model (SSM) of human cochlea. The electrode is simplified as a long and tapered beam of homogeneous elastic materials, contacting and interacting with the stiff cochlear structures. A quasi-static insertion simulation was conducted, the insertion force and the contact pressure between the electrode and the cochlear wall, were calculated to evaluate the smoothness of insertion and the risk of potential cochlear trauma. Based on this model, different EA designs were analyzed, including the Young's modulus, the straight or bended shape, the normal or a more tapped section size. The influence of the insertion angle was also discussed. Our simulations indicate that reducing the EA Young's modulus, tapering and pre-bending are effective ways to ensure safe and successful EA implantation. This model is beneficial for optimizing EA designs and is potentially useful for designing patient-specific CI surgery.
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Affiliation(s)
- Liu-Jie Ren
- Department of Facial Plastic Reconstructive Surgery, ENT Institute, Eye and ENT Hospital, NHC Key Laboratory of Hearing Medicine (Fudan University), Shanghai, 200031, China
| | - Yi Yu
- School of Medical Instrumentation, Shanghai University of Medicine and Health Sciences, Shanghai, 201318, China
| | - Yu-Heng Zhang
- Shanghai Engineering Research Center of Cochlear Implants, Shanghai, 201318, China
| | - Xin-Dong Liu
- Shanghai Engineering Research Center of Cochlear Implants, Shanghai, 201318, China
| | - Zeng-Jun Sun
- Shanghai Engineering Research Center of Cochlear Implants, Shanghai, 201318, China
| | - Wen-Juan Yao
- School of Mechanics and Engineering Science, Shanghai Institute of Applied Mathematics and Mechanics, Shanghai University, Shanghai, 200444, China
| | - Tian-Yu Zhang
- Department of Facial Plastic Reconstructive Surgery, ENT Institute, Eye and ENT Hospital, NHC Key Laboratory of Hearing Medicine (Fudan University), Shanghai, 200031, China
| | - Cheng Wang
- Shanghai Engineering Research Center of Cochlear Implants, Shanghai, 201318, China.
| | - Chen-Long Li
- Department of Facial Plastic Reconstructive Surgery, ENT Institute, Eye and ENT Hospital, NHC Key Laboratory of Hearing Medicine (Fudan University), Shanghai, 200031, China.
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4
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Jwair S, Boerboom RA, Versnel H, Stokroos RJ, Thomeer HGXM. Evaluating cochlear insertion trauma and hearing preservation after cochlear implantation (CIPRES): a study protocol for a randomized single-blind controlled trial. Trials 2021; 22:895. [PMID: 34886884 PMCID: PMC8656003 DOI: 10.1186/s13063-021-05878-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 11/25/2021] [Indexed: 12/26/2022] Open
Abstract
Background In order to preserve residual hearing in patients with sensorineural hearing loss (SNHL) who receive a cochlear implant (CI), insertion trauma to the delicate structures of the cochlea needs to be minimized. The surgical approach comprises the conventional mastoidectomy-posterior tympanotomy (MPT) to arrive at the middle ear, followed by either a cochleostomy (CO) or the round window (RW) approach. Both techniques have their benefits and disadvantages. Another important aspect in structure preservation is the design of the electrode array. Two different designs are used: a “straight” lateral wall lying electrode array (LW) or a “pre-curved” perimodiolar lying electrode array (PM). Interestingly, until now, the best surgical approach and design of the implant is uncertain. Our hypothesis is that there is a difference in hearing preservation outcomes between the four possible treatment options. Methods We designed a monocenter, multi-arm, randomized controlled trial to compare insertion trauma between four groups of patients, with each group having a unique combination of an electrode array type (LW or PM) and surgical approach (RW or CO). In total, 48 patients will be randomized into one of these four intervention groups. Our primary objective is the comparison of postoperative hearing preservation between these four groups. Secondly, we aim to assess structure preservation (i.e., scalar translocation, with basilar membrane disruption or tip fold-over of array) for each group. Thirdly, we will compare objective outcomes of hearing and structure preservation by way of electrocochleography (ECochG). Discussion Cochlear implantation by way of a cochleostomy or round window approach, using different electrode array types, is the standard medical care for patients with severe to profound bilateral sensorineural hearing loss, as it is a relatively simple and low-risk procedure that greatly benefits patients. However, loss of residual hearing remains a problem. This trial is the first randomized controlled trial that evaluates the effect of cochlear insertion trauma of several CI treatment options on hearing preservation. Trial registration Netherlands Trial Register (NTR) NL8586. Registered on 4 May 2020. Retrospectively registered; 3/48 participants were included before registration. Supplementary Information The online version contains supplementary material available at 10.1186/s13063-021-05878-2.
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Affiliation(s)
- Saad Jwair
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht University, P.O. Box 85500, 3508, GA, Utrecht, the Netherlands. .,UMC Utrecht Brain Center, Utrecht University, Utrecht, the Netherlands.
| | - Ralf A Boerboom
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht University, P.O. Box 85500, 3508, GA, Utrecht, the Netherlands.,UMC Utrecht Brain Center, Utrecht University, Utrecht, the Netherlands
| | - Huib Versnel
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht University, P.O. Box 85500, 3508, GA, Utrecht, the Netherlands.,UMC Utrecht Brain Center, Utrecht University, Utrecht, the Netherlands
| | - Robert J Stokroos
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht University, P.O. Box 85500, 3508, GA, Utrecht, the Netherlands.,UMC Utrecht Brain Center, Utrecht University, Utrecht, the Netherlands
| | - Hans G X M Thomeer
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht University, P.O. Box 85500, 3508, GA, Utrecht, the Netherlands.,UMC Utrecht Brain Center, Utrecht University, Utrecht, the Netherlands
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Kamalakkannan A, Johnston PR, Johnston BM. A modified approach to determine the six cardiac bidomain conductivities. Comput Biol Med 2021; 135:104549. [PMID: 34171640 DOI: 10.1016/j.compbiomed.2021.104549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 05/31/2021] [Accepted: 06/01/2021] [Indexed: 11/23/2022]
Abstract
Accurate values for the six cardiac bidomain conductivities are crucial for meaningful computational studies of conduction in cardiac tissue, and are yet to be determined by experimental means. Although previous studies have proposed an approach using a multi-electrode array to measure potentials, from which the conductivities can be determined, it has been found that the conductivities cannot be retrieved consistently when the noise in the potentials varies. This paper presents a protocol, which not only has been shown to retrieve the conductivities to a reasonable accuracy, but does so under the presence of a more appropriate additive Gaussian noise model, while using fewer computational resources. Through repetitions of the protocol, a comparison of two pre-fabricated 128 electrode arrays, one array with a square arrangement of electrodes and the other with a rectangular arrangement, was made against a 75-electrode array proposed in previous studies. Results indicated that the two pre-fabricated arrays were generally more capable of obtaining the cardiac conductivities to a higher degree of accuracy than the 75-electrode array. The 128-electrode rectangular array was orientated such that the length of the array first ran along the direction of the fibres, then was reorientated such that the length of the array ran perpendicular to the direction of the fibres. The 128-electrode rectangular array, when orientated in this manner, was more capable of retrieving the conductivities than the remainder of the arrays tested, and thus we suggest this arrangement be used during experimental trials.
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Kekonen A, Bergelin M, Eriksson JE, Vaalasti A, Ylänen H, Kielosto S, Viik J. Bioimpedance method for monitoring venous ulcers: Clinical proof-of-concept study. Biosens Bioelectron 2021; 178:112974. [PMID: 33524705 DOI: 10.1016/j.bios.2021.112974] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 12/29/2020] [Accepted: 01/04/2021] [Indexed: 11/30/2022]
Abstract
Evaluation of wound status is typically based on means which require the removal of dressings. These procedures are often also subjective and prone to inter-observer bias. To overcome aforementioned issues a bioimpedance measurement-based method and measurement system has been developed to evaluate the state of wound healing. The measurement system incorporated a purpose-built bioimpedance device, a measurement software and a screen-printed electrode array. The feasibility and the performance of the system and method were assessed in an open non-randomized follow-up study of seven venous ulcers. Healing of ulcers was monitored until the complete re-epithelialization was achieved. The duration of follow-up was from 19 to 106 days (mean 55.8 ± 25.2 days). A variable designated as the Wound Status Index (WSI), derived from the bioimpedance data, was used for describing the state of wound healing. The wound surface area was measured using acetate tracing for the reference. A strong correlation was found between the WSI and the acetate tracing data, r(93) = - 0.84, p < 0.001. The results indicate that the bioimpedance measurement-based method is a promising quantitative tool for the evaluation of the status of venous ulcers.
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Affiliation(s)
- Atte Kekonen
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland.
| | - Mikael Bergelin
- Turku PET Centre/Åbo Akademi Accelerator Laboratory, Turku University Hospital, Turku, Finland
| | - Jan-Erik Eriksson
- Johan Gadolin Process Chemistry Centre, Åbo Akademi University, Turku, Finland
| | - Annikki Vaalasti
- Department of Dermatology Outpatient Clinic, Tampere University Hospital, Tampere, Finland
| | - Heimo Ylänen
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Sami Kielosto
- Department of Electrical Engineering and Automation, School of Electrical Engineering, Aalto University, Espoo, Finland
| | - Jari Viik
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
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Molderez TR, Prévoteau A, Ceyssens F, Verhelst M, Rabaey K. A chip-based 128-channel potentiostat for high-throughput studies of bioelectrochemical systems: Optimal electrode potentials for anodic biofilms. Biosens Bioelectron 2021; 174:112813. [PMID: 33303324 DOI: 10.1016/j.bios.2020.112813] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 11/04/2020] [Accepted: 11/08/2020] [Indexed: 11/21/2022]
Abstract
The presence of microorganisms performing extracellular electron transfer has been established in many environments. Research to determine their role is moving slowly due to the high cost of potentiostats and the variance of data with small number of replicates. Here, we present a 128-channel potentiostat, connected to a 128 gold electrode array. Whereas the system is able to perform simultaneously 128 (bio)electrochemical measurements with an independent electrical signal input, the present manufacturing of the array limited the number of effective channels for this study to 77. We assessed the impact of 11 electrode potentials ranging from -0.45V to +0.2V vs. Ag/AgCl (7 replicates per potential) on the growth and electrochemical characteristics of anodic electroactive biofilms (EABs) formed by acetate-fed microbial communities. After 7 days of growth, maximum current was reached for electrodes poised at -0.3V, closely followed by -0.25V and -0.1V to +0.1V, a range well-fitting the midpoint potential of minerals naturally reduced by electroactive bacteria such as Geobacter Sulfurreducens. There was no significant difference in apparent midpoint potential of the EABs (-0.35V), suggesting that the mechanism of heterogeneous electron transfer was not affected by the electrode potential. The EABs poised below current plateau potential (≤-0.3V) exhibited slower growth but higher charge transfer parameters. The high-throughput and high reproducibility provided by the array may have a major facilitating impact on the field of electromicrobiology. Key aspects to improve are data processing algorithms to deal with the vast amount of generated data, and manufacturing of the electrode array itself.
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Ketterer MC, Aschendorff A, Arndt S, Speck I, Rauch AK, Beck R, Hassepass F. Radiological evaluation of a new straight electrode array compared to its precursors. Eur Arch Otorhinolaryngol 2021; 278:3707-14. [PMID: 33090276 DOI: 10.1007/s00405-020-06434-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [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.
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Coutinho da Silva J, Schmidt Goffi-Gomez MV, Tsuji RK, Bento R, Brito Neto R. Is There Any Correlation between Spread of Excitation Width and the Refractory Properties of the Auditory Nerve in Cochlear Implant Users? Audiol Neurootol 2020; 26:85-94. [PMID: 32998132 DOI: 10.1159/000508601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 05/05/2020] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The spread of excitation (SOE) and auditory nerve recovery function (REC) are objective measures recorded by neural response telemetry and may interfere in cochlear implant (CI) stimulation. OBJECTIVE To analyze and correlate SOE with the refractory periods in subjects with pre- and postlingual deafness implanted with different electrode arrays. METHODS This was a retrospective study of 323 ears separated by perimodiolar or straight arrays and by pre- or postlingually deaf recipients. Measures were collected intraoperatively on electrode 11. The SOE width was measured in millimeters at the 0.75 point of the curve, and the relative (tau) and absolute (t0) refractory periods were measured in microseconds. RESULTS There was a statistical correlation between the SOE and the t0 in the patients with postlingual deafness implanted with the perimodiolar array. The SOE width was statistically different between the straight and perimodiolar arrays and between the pre- and postlingual groups in the perimodiolar array. Tau was statistically different between the pre- and postlingual groups with the straight array and the t0, between the pre- and postlingual groups with the perimodiolar array. Neural response threshold and amplitude of the neural response were not statistically different among groups. CONCLUSION There was a correlation between SOE width and t0 only in patients with acquired deafness. The findings suggest that different factors influence SOE and REC, considering SOE is different according to the electrode array and REC being different according the onset of deafness.
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Affiliation(s)
- Juliana Coutinho da Silva
- ENT Department, Hospital das Clínicas da Faculdade de Medicina da Universidade de, São Paulo, Brazil
| | - Maria Valéria Schmidt Goffi-Gomez
- ENT Department, Hospital das Clínicas da Faculdade de Medicina da Universidade de, São Paulo, Brazil, .,Audiology Department, AC Camargo Cancer Center, São Paulo, Brazil,
| | - Robinson Koji Tsuji
- ENT Department, Hospital das Clínicas da Faculdade de Medicina da Universidade de, São Paulo, Brazil
| | - Ricardo Bento
- ENT Department, Hospital das Clínicas da Faculdade de Medicina da Universidade de, São Paulo, Brazil.,ENT Department, Faculdade de Medicina da Universidade de, São Paulo, Brazil
| | - Rubens Brito Neto
- ENT Department, Hospital das Clínicas da Faculdade de Medicina da Universidade de, São Paulo, Brazil.,ENT Department, Faculdade de Medicina da Universidade de, São Paulo, Brazil
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Dhanasingh A. Research software in cochlear duct length estimation, Greenwood frequency mapping and CI electrode array length simulation. World J Otorhinolaryngol Head Neck Surg 2020; 7:17-22. [PMID: 33474539 PMCID: PMC7801236 DOI: 10.1016/j.wjorl.2018.12.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 12/05/2018] [Accepted: 12/11/2018] [Indexed: 11/03/2022] Open
Abstract
Background and objective The size of the cochlea varies a lot among the human population bringing the necessity for electrode arrays to be available in various lengths irrespective of the cochlear implant (CI) brand. This research software helps in the estimation of the patient's cochlear duct length (CDL) which is then used for the simulation of the correct length electrode array matching the patient's cochlear size and as well in getting the patient specific cochlear frequency map. Methods Visual Studio Express 2012 for Windows Desktop is used in the architecture of this research software. The basal turn diameter of the cochlea (“A” value) needs to be measured from the pre-operative computed tomography (CT) image of the patient's temporal bone. This “A” will be taken as the input for the CDL equations proposed by Alexiades et al for estimating the CDL along the basilar membrane for various insertion depths. Greenwood's equation is then used in combination with the CDL for the full length of the cochlea in getting the patient specific frequency map. Results The research software with the help of the “A” value as input, with few button clicks, gives the patient specific CDL for various insertion depths and the Greenwood's frequency map. The users have the choice to select any electrode array of their choice and place it under the frequency map to see how good it fits to that particular patient's cochlea. Also, given the possibility to drag and move the electrode array picture to mimic the post-operative actual electrode insertion depth. Conclusions This research software simplifies the overall process of CDL estimation and in getting the patient specific cochlear frequency map. The clinicians get the chance to simulate placing the various electrode array lengths in patient cochlea in identifying the best fit electrode. This could help in pushing the CI field into the concept of individualized CI electrode array solution that ultimately benefits the patients.
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Garaycochea O, Manrique-Huarte R, Vigliano M, Ferrán de la Cierva S, Manrique M. Sculpting the temporal bone: an easy reversible cochlear implant electro-array stabilization technique. Eur Arch Otorhinolaryngol 2020; 277:1645-1650. [PMID: 32162058 DOI: 10.1007/s00405-020-05895-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 02/28/2020] [Indexed: 11/29/2022]
Abstract
PURPOSE Since the beginning of cochlear implant (CI) surgery, several techniques to fixate the electrode array at the cochleostomy and stabilize it have been described; however, most techniques use autologous tissues such as fascia, muscle, fat or fibrin glue. We describe a new surgical technique aimed to stabilize the electrode array of a CI without using autologous tissues or artificial materials. MATERIALS AND METHODS The surgical technique described consists in creating three stabilizing channels in the temporal bone for the electrode array. The first one in a partially opened aditus, the second one in a partially preserved Koerner's septum (KS) and the last one in the sinodural angle. The procedure was performed in five human temporal bones using a straight array; a radiography was made to confirm the correct placement of the electrode array and afterwards all temporal bones were shaken using a Titramax 1000 platform. The correct placement of the array post-shaking was then confirmed using the microscope and another radiography. RESULTS No migration of the electrodes outside the cochlea was observed. The CI cable remained in the same position at the aditus and the KS in all the temporal bones. In three cases (60%), the electrode array moved away from the groove carved in the sinodural angle. CONCLUSIONS The new surgical technique described stabilizes the electrode array using the temporal bone's normal anatomy, preserving the middle ear spaces, facilitating the ulterior explantation and reimplantation if necessary, and may reduce cost and surgery time.
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Affiliation(s)
- Octavio Garaycochea
- Department of Otorhinolaryngology, Clinica Universitaria de Navarra, University of Navarra, Avenida Pío XII 36, 31008, Pamplona, Spain.
| | - Raquel Manrique-Huarte
- Department of Otorhinolaryngology, Clinica Universitaria de Navarra, University of Navarra, Avenida Pío XII 36, 31008, Pamplona, Spain
| | - Melisa Vigliano
- Department of Otorhinolaryngology, Clinica Universitaria de Navarra, University of Navarra, Avenida Pío XII 36, 31008, Pamplona, Spain
| | - Sol Ferrán de la Cierva
- Department of Otorhinolaryngology, Clinica Universitaria de Navarra, University of Navarra, Avenida Pío XII 36, 31008, Pamplona, Spain
| | - Manuel Manrique
- Department of Otorhinolaryngology, Clinica Universitaria de Navarra, University of Navarra, Avenida Pío XII 36, 31008, Pamplona, Spain
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Abstract
Objectives: The aim of this discussion paper and literature review was to estimate the incidence of a variety of complications associated with the surgical placement of cochlear implant (CI) electrode arrays and to discuss the implications and management of sub-optimal electrode placement. Results: A review of the peer-reviewed literature suggests that the incidence of incomplete electrode insertion and kinking is more prevalent in straight arrays and not more than about 2% in CI recipients with normal cochlear anatomy/patency. Incidence of tip fold-over is greater with perimodiolar arrays but also occurs with straight arrays and is typically less than 5%. Conversely, electrode migration is more common with straight arrays, and high rates (up to 46%) have been reported in some studies. Scalar translocations have also been reported for both perimodiolar and straight arrays. Higher rates have been reported for stylet-based perimodiolar electrodes inserted via cochleostomy (up to 56%), but with much lower rates (<10%) with both sheath-based perimodiolar arrays and lateral wall arrays. Electrode positioning complications represent a significant proportion of perioperative CI complications and compromise the level of benefit from the device. Careful surgical planning and appropriate pre- and intraoperative imaging can reduce the likelihood and impact of electrode positioning complications. There is also evidence that newer array designs are less prone to certain complications, particularly scalar translocation. Conclusions: It is important that implanting surgeons are aware of the impact of sub-optimal electrode placement and the steps that can be taken to avoid, identify and manage such complications.
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Affiliation(s)
- Akira Ishiyama
- Rehabilitation Center, 1000 Veteran Ave., Los Angeles, CA, USA
| | - Frank Risi
- Clinical Affairs, Cochlear Ltd, Macquarie University, Sydney, Australia
| | - Paul Boyd
- Clinical Affairs, Cochlear Ltd, Macquarie University, Sydney, Australia
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Garaycochea O, Manrique-Huarte R, Lazaro C, Huarte A, Prieto C, Alvarez de Linera-Alperi M, Manrique M. Comparative study of two different perimodiolar and a straight cochlear implant electrode array: surgical and audiological outcomes. Eur Arch Otorhinolaryngol 2019; 277:69-76. [PMID: 31637478 DOI: 10.1007/s00405-019-05680-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 10/01/2019] [Indexed: 10/25/2022]
Abstract
PURPOSE To compare the surgical and audiological outcomes with two perimodiolar electrode arrays (Nucleus 512-Contour Advance® y Nucleus 532-Slim Perimodiolar®) and a straight electrode array (Nucleus 422/522). METHODS Patients were retrospectively selected from our cochlear implant program database. Only patients with a history of bilateral, sensorineural postlingually profound hearing loss who underwent cochlear implant surgery with either a N512, a N532 or a N422 were included. Throughout a year of follow-up, pure tone audiometry (PTA), speech perception, Impedances and T-C Thresholds levels were analyzed. Surgical data were also analyzed. RESULTS 66 patients were included (19-CI532, 20-CI512 and 27-CI422). The most common type of cochlea access with the N532, N512 and N422 was through an extended round window, a promontorial cochleostomy and a pure round window, respectively. No significant differences were observed after 12 months in Mean PTA and Speech recognition. No significant differences were seen in the levels of hearing preservation at frequencies of 250 and 500. The average values of the impedances were significantly higher in the CI group N532 and N422 than in the N512. The mean values of the T and C levels were significantly lower in the CI groups N532 and N422 compared with the N512. CONCLUSIONS No significant differences were observed after 12 months in Mean PTA and Speech recognition; however, a faster acquisition of auditory results were observed in the group of patients treated with the CI N532. The type of electrode array influences in the type of cochleostomy.
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Affiliation(s)
- Octavio Garaycochea
- Department of Otorhinolaryngology, Clinica Universitaria de Navarra, Pamplona, Spain.,University of Navarra, Avenida Pío XII 36, 31008, Pamplona, Spain
| | - Raquel Manrique-Huarte
- Department of Otorhinolaryngology, Clinica Universitaria de Navarra, Pamplona, Spain. .,University of Navarra, Avenida Pío XII 36, 31008, Pamplona, Spain.
| | - Carlos Lazaro
- University of Navarra School of Medicine, Pamplona, Spain
| | - Alicia Huarte
- Department of Otorhinolaryngology, Clinica Universitaria de Navarra, Pamplona, Spain.,University of Navarra, Avenida Pío XII 36, 31008, Pamplona, Spain
| | - Carlos Prieto
- Department of Otorhinolaryngology, Clinica Universitaria de Navarra, Pamplona, Spain.,University of Navarra, Avenida Pío XII 36, 31008, Pamplona, Spain
| | - Marta Alvarez de Linera-Alperi
- Department of Otorhinolaryngology, Clinica Universitaria de Navarra, Pamplona, Spain.,University of Navarra, Avenida Pío XII 36, 31008, Pamplona, Spain
| | - Manuel Manrique
- Department of Otorhinolaryngology, Clinica Universitaria de Navarra, Pamplona, Spain.,University of Navarra, Avenida Pío XII 36, 31008, Pamplona, Spain
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Perenyi A, Toth F, Dimak B, Nagy R, Schoerg P, Jori J, Kiss JG, Sprinzl G, Csanady M, Rovo L. Electrophysiological measurements with electrode types of different perimodiolar properties and the same cochlear implant electronics - a retrospective comparison study. J Otolaryngol Head Neck Surg 2019; 48:46. [PMID: 31492190 PMCID: PMC6731597 DOI: 10.1186/s40463-019-0361-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 08/20/2019] [Indexed: 11/23/2022] Open
Affiliation(s)
- A Perenyi
- Department of Otorhinolaryngology, Head and Neck Surgery, University of Szeged, Tisza Lajos krt. 111, Szeged, H-6725, Hungary.
| | - F Toth
- Department of Otorhinolaryngology, Head and Neck Surgery, University of Szeged, Tisza Lajos krt. 111, Szeged, H-6725, Hungary
| | - B Dimak
- Department of Otorhinolaryngology, Head and Neck Surgery, University of Szeged, Tisza Lajos krt. 111, Szeged, H-6725, Hungary
| | - R Nagy
- Department of Otorhinolaryngology, Head and Neck Surgery, University of Szeged, Tisza Lajos krt. 111, Szeged, H-6725, Hungary
| | - P Schoerg
- Karl Landsteiner University Hospital of StPölten, Propst-Führer-Straße 4, 3100, St. Pölten, Austria
| | - J Jori
- Department of Otorhinolaryngology, Head and Neck Surgery, University of Szeged, Tisza Lajos krt. 111, Szeged, H-6725, Hungary
| | - J G Kiss
- Department of Otorhinolaryngology, Head and Neck Surgery, University of Szeged, Tisza Lajos krt. 111, Szeged, H-6725, Hungary
| | - G Sprinzl
- Karl Landsteiner University Hospital of StPölten, Propst-Führer-Straße 4, 3100, St. Pölten, Austria
| | - M Csanady
- Department of Otorhinolaryngology, Head and Neck Surgery, University of Szeged, Tisza Lajos krt. 111, Szeged, H-6725, Hungary
| | - L Rovo
- Department of Otorhinolaryngology, Head and Neck Surgery, University of Szeged, Tisza Lajos krt. 111, Szeged, H-6725, Hungary
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Land R, Kapche A, Ebbers L, Kral A. 32-channel mouse EEG: Visual evoked potentials. J Neurosci Methods 2019; 325:108316. [PMID: 31251949 DOI: 10.1016/j.jneumeth.2019.108316] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 05/31/2019] [Accepted: 06/14/2019] [Indexed: 01/29/2023]
Abstract
BACKGROUND Measuring visual evoked potentials (VEP) by means of EEG allows the quasi non-invasive assessment of visual function in mice. Such sensory phenotyping is important to screen for genetic or aging effects on vision in preclinical mouse models. Thus, a standardized EEG-like approach for the assessment of sensory evoked potentials in mice is desirable. NEW METHOD We describe a method to obtain the topographical distribution of flash evoked VEPs with 32-channel thin-film EEG electrode arrays in anesthetized mice. Further, we provide suggestions for the optimal choice of adequate digital filtering, referencing, and stimulus parameters for fast and reliable assessment of VEP parameters and distribution. RESULTS 32-channel thin-film electrodes provided clear information on the VEP topography across the skull. Re-referencing, such as bipolar, common average, and local average montages could be used to further refine the information on VEP topography. A balanced choice of digital high-pass filter, signal averaging and stimulus rate allowed to minimize measurement duration and at the same time assured good VEP signal-to-noise ratio. COMPARISON WITH EXISTING METHODS Subdermal electrodes or single skull screws provide only limited topographical information of the VEP. Assessment of VEPs with 32-channel thin-film electrodes can provide comparable signal quality with superior spatial resolution and standardized topographical and hemispheric information of VEP distribution. CONCLUSIONS EEG-like thin-film electrodes are an efficient tool for fast, comprehensive sensory phenotyping with topographical information in mice. This is a step towards the use of standardized mouse EEG to characterize EEG biomarkers in mouse models of human diseases.
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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] [What about the content of this article? (0)] [Affiliation(s)] [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.
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Affiliation(s)
- Domenico Cuda
- Department of Otorhinolaryngology, Guglielmo da Saliceto Hospital, Piacenza, Italy
| | - Alessandra Murri
- Department of Otorhinolaryngology, Guglielmo da Saliceto Hospital, Piacenza, Italy
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Tanaka Massuda E, Demarcy T, Hoen M, Danieli F, Arantes do Amaral MS, Gnansia D, Hyppolito MA. Method to quantitatively assess electrode migration from medical images: Feasibility and application in patients with straight cochlear implant arrays. Cochlear Implants Int 2019; 20:237-241. [PMID: 31138089 DOI: 10.1080/14670100.2019.1618525] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Objective: To propose a method for quantitative assessment of the migration of lateral-wall, straight electrode arrays after surgery based on postoperative Cone Beam Computed Tomography (CBCT) images and automated medical image analysis techniques. Methods: A preliminary study is conducted on 19 implanted ears. For each implantation, two CBCT images are objectively analyzed. Electrode arrays are consistently projected into the same coordinate system in order to estimate precisely the migration of each electrode. Spatial configuration changes are characterized with the overall curvature of the electrode array. Results: From the samples analyzed no significant electrode migration, extrusion or electrode curvature changes were found. Mean infinitesimal local migration reveals a tendency where apical electrodes tend to move away from the modiolus and basal electrodes away from the round window. Conclusion: CBCT images demonstrate adequate resolution with limited artifacts to assess the electrode array position in vivo. Automated medical image analysis techniques and consistent coordinate system allow to quantitatively estimate migration and extrusion effect for lateral-wall, straight electrode array.
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Affiliation(s)
- Eduardo Tanaka Massuda
- a Department of Ophthalmology, Otorhinolaryngology, Head and Neck Surgery, Ribeirão Preto Medical School , University of São Paulo , Ribeirão Preto, São Paulo , Brazil
| | - Thomas Demarcy
- b Department of Scientific and Clinical Research , Oticon Medical , Vallauris , France
| | - Michel Hoen
- b Department of Scientific and Clinical Research , Oticon Medical , Vallauris , France
| | - Fabiana Danieli
- c Clinical Department , Oticon Medical , São Paulo , Brazil.,d Postgraduate Program at the Department of Ophthalmology , Otorhinolaryngology, Head and Neck Surgery , Ribeirão Preto , Brazil
| | - Maria Stella Arantes do Amaral
- a Department of Ophthalmology, Otorhinolaryngology, Head and Neck Surgery, Ribeirão Preto Medical School , University of São Paulo , Ribeirão Preto, São Paulo , Brazil.,d Postgraduate Program at the Department of Ophthalmology , Otorhinolaryngology, Head and Neck Surgery , Ribeirão Preto , Brazil
| | - Dan Gnansia
- b Department of Scientific and Clinical Research , Oticon Medical , Vallauris , France
| | - Miguel Angelo Hyppolito
- a Department of Ophthalmology, Otorhinolaryngology, Head and Neck Surgery, Ribeirão Preto Medical School , University of São Paulo , Ribeirão Preto, São Paulo , Brazil
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Abstract
Loss of vision alters the day to day life of blind individuals and may impose a significant burden on their family and the economy. Cortical visual prosthetics have been shown to have the potential of restoring a useful degree of vision via stimulation of primary visual cortex. Due to current advances in electrode design and wireless power and data transmission, development of these prosthetics has gained momentum in the past few years and multiple sites around the world are currently developing and testing their designs. In this review, we briefly outline the visual prosthetic approaches and describe the history of cortical visual prosthetics. Next, we focus on the state of the art of cortical visual prosthesis by briefly explaining the design of current devices that are either under development or in the clinical testing phase. Lastly, we shed light on the challenges of each design and provide some potential solutions.
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Affiliation(s)
- Soroush Niketeghad
- Department of Bioengineering, University of California Los Angeles, Los Angeles, CA, USA
| | - Nader Pouratian
- Department of Bioengineering, University of California Los Angeles, Los Angeles, CA, USA.
- Department of Neurosurgery, University of California Los Angeles, Los Angeles, CA, USA.
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19
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Salchow-Hömmen C, Jankowski N, Valtin M, Schönijahn L, Böttcher S, Dähne F, Schauer T. User-centered practicability analysis of two identification strategies in electrode arrays for FES induced hand motion in early stroke rehabilitation. J Neuroeng Rehabil 2018; 15:123. [PMID: 30594257 PMCID: PMC6310929 DOI: 10.1186/s12984-018-0460-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Accepted: 11/12/2018] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Surface electrode arrays have become popular in the application of functional electrical stimulation (FES) on the forearm. Arrays consist of multiple, small elements, which can be activated separately or in groups, forming virtual electrodes (VEs). As technology progress yields rising numbers of possible elements, an effective search strategy for suitable VEs in electrode arrays is of increasing importance. Current methods can be time-consuming, lack user integration, and miss an evaluation regarding clinical acceptance and practicability. METHODS Two array identification procedures with different levels of user integration-a semi-automatic and a fully automatic approach-are evaluated. The semi-automatic method allows health professionals to continuously modify VEs via a touchscreen while the stimulation intensities are automatically controlled to maintain sufficient wrist extension. The automatic approach evaluates stimulation responses of various VEs for different intensities using a cost function and joint-angles recordings. Both procedures are compared in a clinical setup with five sub-acute stroke patients with moderate hand disabilities. The task was to find suitable VEs in two arrays with 59 elements in total to generate hand opening and closing for a grasp-and-release task. Practicability and acceptance by patients and health professionals were investigated using questionnaires and interviews. RESULTS Both identification methods yield suitable VEs for hand opening and closing in patients who could tolerate the stimulation. However, the resulting VEs differed for both approaches. The average time for a complete search was 25% faster for the semi-automatic approach (semi-automatic: 7.3min, automatic: 10.5min). User acceptance was high for both methods, while no clear preference could be identified. CONCLUSIONS The semi-automatic approach should be preferred as the search strategy in arrays on the forearm. The observed faster search duration will further reduce when applying the system repeatedly on a patient as only small position adjustments for VEs are required. However, the setup time will significantly increase for generation of various grasp types and adaptation to different arm postures. We recommend different levels of user integration in FES systems such that the search strategy can be chosen based on the users' preferences and application scenario.
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Affiliation(s)
| | - Natalie Jankowski
- Institut für Rehabilitationswissenschaften, Humboldt Universität zu Berlin, Unter den Linden 6, Berlin, 10099 Germany
| | - Markus Valtin
- Control Systems Group, Technische Universität Berlin, Einsteinufer 17, Berlin, 10587 Germany
| | - Laura Schönijahn
- Institut für Rehabilitationswissenschaften, Humboldt Universität zu Berlin, Unter den Linden 6, Berlin, 10099 Germany
| | - Sebastian Böttcher
- Klinik für Neurologie mit Stroke Unit und Frührehabilitation, Unfallkrankenhaus Berlin, Warener Str. 7, Berlin, 12683 Germany
| | - Frank Dähne
- Klinik für Neurologie mit Stroke Unit und Frührehabilitation, Unfallkrankenhaus Berlin, Warener Str. 7, Berlin, 12683 Germany
| | - Thomas Schauer
- Control Systems Group, Technische Universität Berlin, Einsteinufer 17, Berlin, 10587 Germany
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Hatsuzawa T, Kurosaka M. A cell culture device equipped with a micro-needle electrode array fabricated using backside exposure mold and resin casting. Biomed Microdevices 2018; 20:58. [PMID: 29998380 DOI: 10.1007/s10544-018-0303-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
A cell culture device equipped with a micro-needle electrode array was fabricated for the signal analysis of cell spheroids, cell masses, and cell sheets. For the analysis, sharp needle electrodes with a high aspect ratio for facilitating easy penetration into the cell mass and a small pitch for fine spatial resolution were required. Microelectromechanical systems (MEMS) technology is one of the common solutions for the fabrication of devices. However, an additional process, such as anisotropic etching or electro-polishing, is required for fabricating sharp needles. Tapered needles were fabricated using backside exposure for coating a layer of thick resist film on a glass substrate. The incident beam from mask apertures were diffracted and attenuated in the medium, resulting in tapered intensity distribution. A needle-like shape was obtained after performing resist development without using additional MEMS process. In this study, the theoretical analysis of optical intensity distribution and design and fabrication process of the device were described. Finally, the effectiveness of the device was evaluated by adding cultured cell mass on the needle array. Signals with spikes and fluctuations were observed in the electrode covered with cell mass, whereas only noise was observed on the non-covered electrode, demonstrating the signal pick-up ability of the device during cell culture.
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Affiliation(s)
- Takeshi Hatsuzawa
- Laboratory for Future Interdisciplinary Research of Science and Technology(FIRST), Tokyo Institute of Technology, 4259-R2-6, Nagatsuta-cho, midori-ku, Yokohama, 226-8503, Japan.
| | - Mikiya Kurosaka
- School of Engineering, Department of Mechanical Engineering, Tokyo Institute of Technology, 4259-R2-6, Nagatsuta-cho, midori-ku, Yokohama, 226-8503, Japan
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Abou-Al-Shaar H, Brock AA, Kundu B, Englot DJ, Rolston JD. Increased nationwide use of stereoencephalography for intracranial epilepsy electroencephalography recordings. J Clin Neurosci 2018; 53:132-134. [PMID: 29724650 PMCID: PMC6188665 DOI: 10.1016/j.jocn.2018.04.064] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 04/22/2018] [Indexed: 01/04/2023]
Abstract
Intracranial electroencephalography (iEEG) can be performed using minimally invasive stereo-electroencephalography (SEEG) or by implanting subdural electrodes via a craniotomy or multiple burr holes. There is anecdotal evidence that SEEG is becoming more common in the United States, though this has yet to be quantified. To address this question, all SEEG and burr hole/craniotomy subdural iEEG procedures were extracted from the Centers for Medicare and Medicaid Services Part B data files for the years 2000-2016. National trends were compared over time. In 2016, SEEG became the most frequently performed intracranial monitoring procedure in the Medicare population, increasing from 28.8% of total cases in 2000 to 43.1% in 2016 (p = 0.02). The proportion of strip electrode cases (through burr holes) significantly declined, while the frequency of craniotomies for subdural grid placement did not significantly change. These data are consistent with a nationwide increase in the utilization of SEEG with a concomitant decline in burr hole placement of subdural strip electrodes in the United States. The factors driving these changes are unknown, but are likely due in part to the desire for minimally invasive surgical options.
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Affiliation(s)
- Hussam Abou-Al-Shaar
- Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, Salt Lake City, UT, United States
| | - Andrea A Brock
- Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, Salt Lake City, UT, United States
| | - Bornali Kundu
- Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, Salt Lake City, UT, United States
| | - Dario J Englot
- Department of Neurosurgery, Vanderbilt University, Nashville, TN, United States
| | - John D Rolston
- Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, Salt Lake City, UT, United States.
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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: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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.
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23
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Maruyama Y, Ito H. Design of multi electrode arrays for uniform sampling of different orientations of tuned unit populations in the cat visual cortex. Neurosci Res 2017; 122:51-63. [PMID: 28432013 DOI: 10.1016/j.neures.2017.04.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 04/07/2017] [Accepted: 04/13/2017] [Indexed: 11/23/2022]
Abstract
For better reconstruction of stimulus orientation from a single trial activity of the neuron population in the visual cortex, we need uniform samplings of differently oriented tuned neurons. We recorded multiple neurons simultaneously by using either a four-tetrode array or an eight-microelectrode array, and examined what kinds of electrodes and layouts provided a more homogeneous distribution of the units' optimal orientations. The unit population sampled by a four-tetrode array showed more homogeneous distribution than those sampled by an eight-microelectrode array. We confirmed this property by simulated recording sessions based on the optical imaging data of the orientation map.
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Lathuillière M, Merklen F, Piron JP, Sicard M, Villemus F, Menjot de Champfleur N, Venail F, Uziel A, Mondain M. Cone-beam computed tomography in children with cochlear implants: The effect of electrode array position on ECAP. Int J Pediatr Otorhinolaryngol 2017; 92:27-31. [PMID: 28012529 DOI: 10.1016/j.ijporl.2016.10.033] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 10/24/2016] [Accepted: 10/26/2016] [Indexed: 11/25/2022]
Abstract
OBJECTIVES To assess the feasibility of using cone-beam computed tomography (CBCT) in young children with cochlear implants (CIs) and study the effect of intracochlear position on electrophysiological and behavioral measurements. METHODS A total of 40 children with either unilateral or bilateral cochlear implants were prospectively included in the study. Electrode placement and insertion angles were studied in 55 Cochlear® implants (16 straight arrays and 39 perimodiolar arrays), using either CBCT or X-ray imaging. CBCT or X-ray imaging were scheduled when the children were leaving the recovery room. We recorded intraoperative and postoperative neural response telemetry threshold (T-NRT) values, intraoperative and postoperative electrode impedance values, as well as behavioral T (threshold) and C (comfort) levels on electrodes 1, 5, 10, 15 and 20. RESULTS CBCT imaging was feasible without any sedation in 24 children (60%). Accidental scala vestibuli insertion was observed in 3 out of 24 implants as assessed by CBCT. The mean insertion angle was 339.7°±35.8°. The use of a perimodiolar array led to higher angles of insertion, lower postoperative T-NRT, as well as decreased behavioral T and C levels. We found no significant effect of either electrode array position or angle of insertion on electrophysiological data. CONCLUSION CBCT appears to be a reliable tool for anatomical assessment of young children with CIs. Intracochlear position had no significant effect on the electrically evoked compound action potential (ECAP) threshold. Our CBCT protocol must be improved to increase the rate of successful investigations.
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Affiliation(s)
- Marine Lathuillière
- Cochlear Implant Centre, Ear Nose and Throat Department, University Hospital Gui-de-Chauliac, Montpellier, France.
| | - Fanny Merklen
- Cochlear Implant Centre, Ear Nose and Throat Department, University Hospital Gui-de-Chauliac, Montpellier, France
| | - Jean-Pierre Piron
- Cochlear Implant Centre, Ear Nose and Throat Department, University Hospital Gui-de-Chauliac, Montpellier, France
| | - Marielle Sicard
- Cochlear Implant Centre, Ear Nose and Throat Department, University Hospital Gui-de-Chauliac, Montpellier, France
| | - Françoise Villemus
- Cochlear Implant Centre, Ear Nose and Throat Department, University Hospital Gui-de-Chauliac, Montpellier, France
| | | | - Frédéric Venail
- Cochlear Implant Centre, Ear Nose and Throat Department, University Hospital Gui-de-Chauliac, Montpellier, France
| | - Alain Uziel
- Cochlear Implant Centre, Ear Nose and Throat Department, University Hospital Gui-de-Chauliac, Montpellier, France
| | - Michel Mondain
- Cochlear Implant Centre, Ear Nose and Throat Department, University Hospital Gui-de-Chauliac, Montpellier, France
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25
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Abstract
Today increasing numbers of cochlear implant candidates have residual hearing that can be aided and hence is worth trying to preserve. This means that surgical technique and electrode array design must be adapted to minimize trauma. Wide opening of the round window is often preferred to reduce drill related trauma and to avoid pressure spikes during electrode array insertion. A recent meta-analysis suggested that there is no significant correlation between hearing preservation and either insertion depth or scala position. However, a slow insertion speed of at least 30seconds was associated with better hearing preservation. An electrode design is proposed that targets the middle of the scala tympani. This minimizes frictional forces from either lateral or medial wall during insertion and imposes less static pressure on cochlear structures following insertion. The flexibility to insert via the round window requires a 0.7-mm maximum dimension at the proximal end of the array. Micro-anatomical analysis by micro-CT indicated that a 420-degree insertion depth was optimal between cochlear coverage and available space within the scala tympani. Physical measurements showed that mean insertion forces remained below 10mN during insertion. A series of 20 human temporal bone insertions found a mean insertion depth of 400 degrees with no scala dislocations. Six clinical series, in total 94 cases, found postoperative hearing in 81% of cases with a mean loss of 12dB compared to preoperative levels. Speech understanding out to one year post-fitting trended better for a mid-scala design group than for a straight electrode array group; although the differences were not statistically significant. A mid-scala array design appears able to be inserted with minimal trauma, to return a predictable insertion depth across various sizes of cochleae and to support reasonable levels of speech understanding without relying on residual hearing.
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Affiliation(s)
- P J Boyle
- European Research Center, Advanced Bionics GmbH, Hannover, Germany.
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Xiao Y, Johnson MD. Spherical statistics for characterizing the spatial distribution of deep brain stimulation effects on neuronal activity. J Neurosci Methods 2015; 255:52-65. [PMID: 26275582 DOI: 10.1016/j.jneumeth.2015.08.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 07/29/2015] [Accepted: 08/01/2015] [Indexed: 11/24/2022]
Abstract
BACKGROUND Computational models of deep brain stimulation (DBS) have played a key role in understanding its physiological mechanisms. By estimating a volume of tissue directly modulated by DBS, one can relate the neuronal pathways within those volumes to the therapeutic efficacy of a particular DBS setting. NEW METHOD A spherical statistical framework is described to quantify and determine salient features of such morphologies using visualization techniques, empirical shape analysis, and formal hypothesis testing. This framework is shown using a 3D model of thalamocortical neurons surrounding a radially-segmented DBS array. RESULTS We show that neuronal population volumes modulated by various DBS electrode configurations can be characterized by parametric distribution models, such as Kent and Watson girdle models. Distribution parameters were found to change with stimulus settings, including amplitude and radial distance from the DBS array. Increasing stimulation amplitude through a single electrode resulted in more diffuse neuronal activation and increased rotational symmetry about the mean direction of the activated population. When stimulation amplitude was held constant, the activated neuronal population distribution was more concentrated with distance from the DBS array and was also more rotationally asymmetric. We also show how data representation (e.g. stimulus-entrained cell body vs. axon node) can significantly alter model distribution shape. COMPARISON TO EXISTING METHODS This statistical framework provides a quantitative method to analyze the spatial morphologies of DBS-induced effects on neuronal activity. CONCLUSIONS The application of spherical statistics to assess spatial distributions of neuronal activity has potential usefulness for numerous other recording, labeling, and stimulation modalities.
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Mom T, Bachy A, Houette A, Pavier Y, Pastourel R, Gabrillargues J, Saroul N, Gilain L, Avan P. Cochlear implantation through the round window with a straight slotted electrode array: optimizing the surgical procedure. Eur Arch Otorhinolaryngol 2015; 273:853-8. [PMID: 25894503 DOI: 10.1007/s00405-015-3623-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 04/04/2015] [Indexed: 11/29/2022]
Abstract
The question addressed here is how optimizing the quality of insertion through the round window with the lower morbidity, when using a straight and slotted electrode array of regular length. This retrospective analysis includes all cases implanted with a cochlear implant Digisonic SP (Neurelec-Oticon Medical) since 2004. We checked the operative charts, the depth of insertion, and the follow-up. For comparisons, contingency tables were used and a Chi-square test was performed. A p value <0.05 was considered significant. 126 cases of patients with non-malformed cochleas were implanted through the round window. The mean age was 53.8 ± 16.2 for adults and 3.6 ± 2.6 for children (24 cases). The mean follow-up was 33 ± 22 months. The straight electrode array had either a square or a soft pointed tip (n = 84). Full insertion was achieved in 79 out of 84 cases with a soft tip vs. 18 out of 42 square tips (χ (2) = 41.41, DOF = 1, p < 0.0001). Two cases were stuck at the round window niche by a prominent crista fenestrae. In all cases but one, the chorda tympany was preserved. In one case, a misrouting to the vestibule required a revision surgery. Implantation through the round window with a straight and slotted electrode array with a soft tip (Digisonic SP, Neurelec-Oticon Medical) can lead to a full insertion in 94 % of cases. Drilling out a prominent crista fenestrae is recommended.
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Affiliation(s)
- Thierry Mom
- Department of Otolaryngology Head and Neck Surgery, University Hospital Center CHU Gabriel Montpied, Université d'Auvergne Clermont 1, 30 place Henri Dunant, 63000, Clermont-Ferrand, France.
- Laboratory of Biophysics of Sensorineureal Handicaps, Faculty of Medicine, INSERM-UMR 1107, Université d'Auvergne Clermont 1, Clermont-Ferrand, France.
| | - Aurélie Bachy
- Department of Otolaryngology Head and Neck Surgery, University Hospital Center CHU Gabriel Montpied, Université d'Auvergne Clermont 1, 30 place Henri Dunant, 63000, Clermont-Ferrand, France
| | - Aubry Houette
- Department of Otolaryngology Head and Neck Surgery, University Hospital Center CHU Gabriel Montpied, Université d'Auvergne Clermont 1, 30 place Henri Dunant, 63000, Clermont-Ferrand, France
| | - Yoann Pavier
- Department of Otolaryngology Head and Neck Surgery, University Hospital Center CHU Gabriel Montpied, Université d'Auvergne Clermont 1, 30 place Henri Dunant, 63000, Clermont-Ferrand, France
- Laboratory of Biophysics of Sensorineureal Handicaps, Faculty of Medicine, INSERM-UMR 1107, Université d'Auvergne Clermont 1, Clermont-Ferrand, France
| | - Rémy Pastourel
- Department of Otolaryngology Head and Neck Surgery, University Hospital Center CHU Gabriel Montpied, Université d'Auvergne Clermont 1, 30 place Henri Dunant, 63000, Clermont-Ferrand, France
| | - Jean Gabrillargues
- Department of Neuroradiology, University Hospital Center CHU Gabriel Montpied, Université d'Auvergne Clermont 1, 30 place Henri Dunant, 63000, Clermont-Ferrand, France
| | - Nicolas Saroul
- Department of Otolaryngology Head and Neck Surgery, University Hospital Center CHU Gabriel Montpied, Université d'Auvergne Clermont 1, 30 place Henri Dunant, 63000, Clermont-Ferrand, France
| | - Laurent Gilain
- Department of Otolaryngology Head and Neck Surgery, University Hospital Center CHU Gabriel Montpied, Université d'Auvergne Clermont 1, 30 place Henri Dunant, 63000, Clermont-Ferrand, France
- Laboratory of Biophysics of Sensorineureal Handicaps, Faculty of Medicine, INSERM-UMR 1107, Université d'Auvergne Clermont 1, Clermont-Ferrand, France
| | - Paul Avan
- Laboratory of Biophysics of Sensorineureal Handicaps, Faculty of Medicine, INSERM-UMR 1107, Université d'Auvergne Clermont 1, Clermont-Ferrand, France
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Sun JQ, Sun JW, Hou XY, Bie YZ, Chen JW. Electrode array misplacement into the superior semicircular canal: as a rare complication of cochlear implantation. Int J Pediatr Otorhinolaryngol 2014; 78:1537-40. [PMID: 25063507 DOI: 10.1016/j.ijporl.2014.06.033] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2014] [Revised: 06/27/2014] [Accepted: 06/28/2014] [Indexed: 11/22/2022]
Abstract
OBJECTIVE To report electrode array misplacement into the superior semicircular canal occurring as an rare complication of cochlear implantation through round window insertion, and to explore the causative association between electrode array misplacement and cochlear implantation surgical techniques. METHODS A chart review of the electrode array misplacement into the superior semicircular canal and their management in 695 patients undergoing cochlear implantation was undertaken from January 2003 and January 2014 in Anhui Provincial Hospital. RESULTS There were two children of electrode array misplacement into the superior semicircular canal complication, and the rate was 0.28%. CONCLUSIONS Electrode array misplacement into the superior semicircular canal associated with cochlear implantation is rare. Surgeons should be aware of that the smaller round window maybe the reason of electrode array misplacement through round window insertion. Intra-operative neural response telemetry and X-ray can alert the surgeon the problem with the array's misplacement, which can be identified by postoperative CT.
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