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Suri N, Sharma D. Importance of preoperative HRCT temporal bone in the orientation of the cochlea and its relation to intra-operative difficulties in cochlear implantation - predicting the grades of difficulty. Cochlear Implants Int 2024:1-8. [PMID: 38812414 DOI: 10.1080/14670100.2024.2358621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2024]
Abstract
OBJECTIVE This study emphasizes the role of preoperative high-resolution computed tomography (HRCT) temporal bone in evaluating the variation in cochlear orientation and proposes a grading system to determine the level of intraoperative difficulties encountered. METHODS Preoperative correlation of middle ear and inner ear structures along with the basal turn angle (BTA) was done to assess the orientation. Patients were divided into three groups depending on BTA and radiology findings. RESULTS Group A (BTA = 55°-60°) had statistically significant (p < 0.05) correlation between middle ear to inner ear structures on HRCT, whereas group B (BTA >60°) and C (BTA <55°) had variations in the alignment of middle ear structures to their corresponding inner ear structures. CONCLUSION The association of BTA to the correlation between middle ear and inner ear structures can determine the orientation of the cochlea. This evaluation makes the surgeon aware of intraoperative challenges and helps in surgical planning.
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Affiliation(s)
- Neeraj Suri
- Department of ENT, GMERS Medical College, Gandhinagar, Gujarat, India
| | - Diva Sharma
- Department of ENT, GMERS Medical College, Gandhinagar, Gujarat, India
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Greisiger R, Bester C, Sørensen T, Korslund H, Bunne M, O'Leary S, Jablonski GE. Intraoperative Measured Electrocochleography and Fluoroscopy Video to Detect Cochlea Trauma. Otol Neurotol 2024; 45:36-45. [PMID: 38085760 DOI: 10.1097/mao.0000000000004055] [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: 12/18/2023]
Abstract
HYPOTHESIS Gross electrode movements detected with intraoperative, real-time X-ray fluoroscopy will correlate with fluctuations in cochlear output, as measured with intraoperative electrocochleography (ECochG). BACKGROUND Indications for cochlear implantation (CI) are expanding to include patients with residual hearing; however, implant recipients often lose residual hearing after CI. The objective of this study was to identify probable traumatic events during implantation by combining electrophysiological monitoring of cochlear function with simultaneous X-ray monitoring. The surgical timing of these apparently traumatic events was then investigated. METHODS For 19 adult patients (21 surgeries, 2 bilateral), the ECochG responses were measured during implantation of a cochlear nucleus slim modiolar electrode (CI532/CI632, Cochlear Ltd Australia Nucleus slim modiolar). Simultaneous fluoroscopy was performed, as well as a postoperative cone-beam computed tomography (CT) scan. For all patients, pre- and postoperative audiograms were recorded up to 1 year after surgery to record the loss of residual hearing. RESULTS Electrode insertions for 21 surgeries were successfully monitored. A drop in ECochG response was significantly correlated with reduced hearing preservation compared with patients with preserved responses throughout. Drops in the ECochG response were measured to occur during insertion, because of movement of the array after insertion was complete, including while sealing of the electrode array at the round window or coiling of the array lead within the mastoid cavity. In some patients, a reduction in cochlear output, resulting in poor ECochG response, was inferred to occur before the beginning of implantation. CONCLUSION The combination of perioperative ECochG measurements, microscope video, fluoroscopy, and postoperative CT scan may inform on what causes the loss of residual hearing after implantation. These findings will be used to improve the surgical procedure in future.
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Affiliation(s)
- Ralf Greisiger
- Department of Otorhinolaryngology and Head and Neck Surgery, Oslo University Hospital, Oslo, Norway
| | - Christofer Bester
- Department of Surgery-Otolaryngology, University of Melbourne, Melbourne, Australia
| | - Torquil Sørensen
- Department of Otorhinolaryngology and Head and Neck Surgery, Oslo University Hospital, Oslo, Norway
| | | | - Marie Bunne
- Department of Otorhinolaryngology and Head and Neck Surgery, Oslo University Hospital, Oslo, Norway
| | - Stephen O'Leary
- Department of Surgery-Otolaryngology, University of Melbourne, Melbourne, Australia
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3
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Engert J, Bauer D, Spahn B, Müller-Graff FT, Voelker J, Neun T, Althoff D, Hagen R, Hackenberg S, Rak K. Computed tomographic 3D analysis of the cochlear aqueduct-potential and limitations of clinical imaging. Acta Otolaryngol 2023; 143:931-935. [PMID: 38127466 DOI: 10.1080/00016489.2023.2294921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 12/07/2023] [Indexed: 12/23/2023]
Abstract
Background: The cochlear aqueduct (CA), which connects the scala tympani and the subarachnoid space, and its accompanying structures appear to have a significant relevance during cochlear implantation and an accurate visualization in clinical imaging is of great interest. Aims and Objective: This study aims to determine which potential and limitations clinically available imaging modalities have in the visualization of the CA. Methods: Micro-CT, flat-panel volume computed tomography with and without secondary reconstruction (fpVCT, fpVCTseco) and multislice computed tomography (MSCT) of 10 temporal bone specimen were used for 3D analysis of the CA. Results: FpVCTseco proved superior in visualizing the associated structures and lateral portions of the CA, which merge into the basal turn of the cochlea. All clinical imaging modalities proved equal in analyzing the length, total volume of the CA and its area of the medial orifice. Conclusion: The choice of the most accurate clinical imaging modality to evaluate the CA and its associated structures depends on the clinical or scientific question. Furthermore, this study should provide a basis for further investigations analyzing the CA.
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Affiliation(s)
- Jonas Engert
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery, University of Wuerzburg, Wuerzburg, Germany
| | - Daniel Bauer
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery, University of Wuerzburg, Wuerzburg, Germany
| | - Bjoern Spahn
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery, University of Wuerzburg, Wuerzburg, Germany
| | - Franz-Tassilo Müller-Graff
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery, University of Wuerzburg, Wuerzburg, Germany
| | - Johannes Voelker
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery, University of Wuerzburg, Wuerzburg, Germany
| | - Tilmann Neun
- Institute for Diagnostic and Interventional Neuroradiology, University of Wuerzburg, Wuerzburg, Germany
| | - Daniel Althoff
- Fraunhofer Development Center for X-ray Technology, Wuerzburg, Germany
| | - Rudolf Hagen
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery, University of Wuerzburg, Wuerzburg, Germany
| | - Stephan Hackenberg
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery, University of Wuerzburg, Wuerzburg, Germany
| | - Kristen Rak
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery, University of Wuerzburg, Wuerzburg, Germany
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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.
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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.
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Optical Coherence Tomography-Based Atlas of the Human Cochlear Hook Region. J Clin Med 2022; 12:jcm12010238. [PMID: 36615042 PMCID: PMC9820872 DOI: 10.3390/jcm12010238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 12/22/2022] [Accepted: 12/23/2022] [Indexed: 12/30/2022] Open
Abstract
Advancements in intracochlear diagnostics, as well as prosthetic and regenerative inner ear therapies, rely on a good understanding of cochlear microanatomy. The human cochlea is very small and deeply embedded within the densest skull bone, making nondestructive visualization of its internal microstructures extremely challenging. Current imaging techniques used in clinical practice, such as MRI and CT, fall short in their resolution to visualize important intracochlear landmarks, and histological analysis of the cochlea cannot be performed on living patients without compromising their hearing. Recently, optical coherence tomography (OCT) has been shown to be a promising tool for nondestructive micrometer resolution imaging of the mammalian inner ear. Various studies performed on human cadaveric tissue and living animals demonstrated the ability of OCT to visualize important cochlear microstructures (scalae, organ of Corti, spiral ligament, and osseous spiral lamina) at micrometer resolution. However, the interpretation of human intracochlear OCT images is non-trivial for researchers and clinicians who are not yet familiar with this novel technology. In this study, we present an atlas of intracochlear OCT images, which were acquired in a series of 7 fresh and 10 fresh-frozen human cadaveric cochleae through the round window membrane and describe the qualitative characteristics of visualized intracochlear structures. Likewise, we describe several intracochlear abnormalities, which could be detected with OCT and are relevant for clinical practice.
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Singh J, Singh RK, Mishra SK, Jha S. Effect of the vertical facial canal to round window distance concerning neural response telemetry during cochlear implantation in children. Int J Pediatr Otorhinolaryngol 2022; 163:111349. [PMID: 36308882 DOI: 10.1016/j.ijporl.2022.111349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Revised: 05/29/2022] [Accepted: 10/11/2022] [Indexed: 11/07/2022]
Abstract
OBJECTIVE To assess the correlation of the distance from the round window (RW) to the vertical facial canal (VFC) with neural response telemetry thresholds (T-NRT), which may have an influence on the insertion trajectory and aid in preoperative surgical planning and electrode selection. METHODS An observational study was conducted on 30 prelingually deaf children under five years diagnosed with bilateral severe to profound hearing loss and received a cochlear implant. The preoperative high resolution computed tomography (HRCT) images in the axial cut bone window setting at the round window level was used to calculate the distance from the RW to the VFC on the RadiAnt DICOM Viewer. The intraoperative distance was measured with ScopyDoc version 8.2.4 software. In Auto-NRT mode, software-based recordings (Cochlear's Custom Sound EP 6.0) were used to measure and evaluate the T-NRT current level. RESULTS A statistically significant positive correlation of the RW to VFC distance with the average T-NRT p = 0.02, r = -0.4 and with the mid-frequency, T-NRT p = 0.003, r = -0.5 was found. CONCLUSION The insertion trajectory can be ascertained by a statistically significant correlation between average T-NRT and mid-frequency T-NRT with RW and VFC distance, and this reliable factor can be taken into account in future surgical technique modulation, electrode selection, and electrode design.
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Affiliation(s)
- Jyoti Singh
- Department of ENT, Indira Gandhi Institute of Medical Sciences, Patna, India
| | - Rakesh Kumar Singh
- Department of ENT, Indira Gandhi Institute of Medical Sciences, Patna, India.
| | | | - Shruti Jha
- Department of ENT, Indira Gandhi Institute of Medical Sciences, Patna, India
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Juliano AF, D'Arco F, Pao J, Picariello S, Clement E, Moonis G, Robson CD. The Cochlea in Branchio-Oto-Renal Syndrome: An Objective Method for the Diagnosis of Offset Cochlear Turns. AJNR Am J Neuroradiol 2022; 43:1646-1652. [PMID: 36175083 PMCID: PMC9731253 DOI: 10.3174/ajnr.a7653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 08/19/2022] [Indexed: 02/01/2023]
Abstract
BACKGROUND AND PURPOSE An "unwound" or "offset" cochlea has been described as a characteristic imaging feature in patients with branchio-oto-renal syndrome, and recently recognized to be associated in particular to those with EYA1 gene mutations. Determination of this feature has traditionally relied on subjective visual assessment. Our aim was to establish an objective assessment method for cochlear offset (the cochlear turn alignment ratio) and determine an optimal cutoff turn alignment ratio value that separates individuals with EYA1-branchio-oto-renal syndrome from those with SIX1-branchio-oto-renal syndrome and healthy controls. MATERIALS AND METHODS Temporal bone CT or MR imaging from 40 individuals with branchio-oto-renal syndrome and 40 controls was retrospectively reviewed. Cochlear offset was determined visually by 2 independent blinded readers and then quantitatively via a standardized technique yielding the cochlear turn alignment ratio. The turn alignment ratio values were compared between cochleae qualitatively assessed as "not offset" and "offset." Receiver operating characteristic analysis was used to determine the ability of the turn alignment ratio to differentiate between these populations and an optimal cutoff turn alignment ratio value. Cochlear offset and turn alignment ratio values were analyzed for each branchio-oto-renal syndrome genotype subpopulation and for controls. RESULTS The turn alignment ratio can accurately differentiate between cochleae with and without an offset (P < .001). The optimal cutoff value separating these populations was 0.476 (sensitivity = 1, specificity = 0.986, J = 0.986). All except 1 cochlea among the EYA1-branchio-oto-renal syndrome subset and all with unknown genotype branchio-oto-renal syndrome had a cochlear offset and a turn alignment ratio of <0.476. All except 1 cochlea among the SIX1-branchio-oto-renal syndrome subset and all controls had no offset and a turn alignment ratio of >0.476. CONCLUSIONS There is a statistically significant difference in turn alignment ratios between offset and nonoffset cochleae, with an optimal cutoff of 0.476. This cutoff value allows excellent separation of EYA1-branchio-oto-renal syndrome from SIX1-branchio-oto-renal syndrome and from individuals without branchio-oto-renal syndrome or sensorineural hearing loss. The turn alignment ratio is a reliable and objective metric that can aid in the imaging evaluation of branchio-oto-renal syndrome.
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Affiliation(s)
- A F Juliano
- From the Department of Radiology (A.F.J.), Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts
| | - F D'Arco
- Department of Radiology (F.D.), Great Ormond Street Hospital for Children, London, UK
| | - J Pao
- Department of Radiology (J.P.), Orlando Health, Orlando Regional Medical Center, Orlando, Florida
| | - S Picariello
- Department of General and Specialized Surgery for Women and Children (S.P.), University of Campania "Luigi Vanvitelli," Naples, Italy
- Neuro-Oncology Unit (S.P.), Department of Paediatric Oncology, Santobono-Pausilipon Children's Hospital, Naples, Italy
| | - E Clement
- Department of Clinical Genetics (E.C.), Great Ormond Street Hospital for Children National Health Service Foundation Trust, London, UK
| | - G Moonis
- Department of Radiology (G.M.), NYU Langone Medical Center, New York, New York
| | - C D Robson
- Department of Radiology (C.D.R.), Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
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Pao J, D’Arco F, Clement E, Picariello S, Moonis G, Robson C, Juliano A. Re-Examining the Cochlea in Branchio-Oto-Renal Syndrome: Genotype-Phenotype Correlation. AJNR Am J Neuroradiol 2022; 43:309-314. [PMID: 35058298 PMCID: PMC8985666 DOI: 10.3174/ajnr.a7396] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Accepted: 11/02/2021] [Indexed: 02/03/2023]
Abstract
BACKGROUND AND PURPOSE Temporal bone imaging plays an important role in the work-up of branchio-oto-renal syndrome. Previous reports have suggested that the unwound or offset cochlea is a highly characteristic marker for branchio-oto-renal syndrome. Our goals were to examine the prevalence of this finding in a branchio-oto-renal syndrome cohort and analyze genetic-phenotypic associations not previously established. MATERIALS AND METHODS This multicenter retrospective study included 38 ears in 19 unrelated individuals with clinically diagnosed branchio-oto-renal syndrome and confirmed mutations in the EYA1 or SIX1 genes. Two blinded neuroradiologists independently reviewed and documented temporal bone imaging findings in 13 categories for each ear. Imaging phenotypes were correlated with genotypes. RESULTS There was excellent interrater agreement for all 13 phenotypic categories (κ ≥ 0.80). Of these, 9 categories showed statistically significant differences between patients with EYA1-branchio-oto-renal syndrome and SIX1-branchio-oto-renal syndrome. Cochlear offset was present in 100% of patients with EYA1-branchio-oto-renal syndrome, but in only 1 ear (12.5%) among patients with SIX1-branchio-oto-renal syndrome. A short thorny appearance of the cochlear apical turn was observed in most patients with SIX1-branchio-oto-renal syndrome. CONCLUSIONS An offset cochlea is associated with the EYA1-branchio-oto-renal syndrome genotype. The SIX1-branchio-oto-renal syndrome genotype is associated with a different cochlear phenotype that almost always is without offset and has a short thorny tip as the apical turn. Therefore, cochlear offset is not a characteristic marker for all patients with branchio-oto-renal syndrome. The lack of a cochlear offset in a patient with clinically suspected branchio-oto-renal syndrome does not exclude the diagnosis and, in fact, may be predictive of the SIX1 genotype.
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Affiliation(s)
- J. Pao
- From the Department of Radiology (J.P.), Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts
| | | | - E. Clement
- Department of Clinical Genetics (E.C.), Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - S. Picariello
- Department of Women, Child and General and Specialized Surgery (S.P.), University of Campania “Luigi Vanvitelli,” Naples, Italy,Department of Paediatric Oncology (S.P.), Neuro-Oncology Unit, Santobono-Pausilipon Children’s Hospital, Naples, Italy
| | - G. Moonis
- Department of Radiology (G.M.), Columbia University Irving Medical Center, New York, New York
| | - C.D. Robson
- Department of Radiology (C.D.R.), Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts
| | - A.F. Juliano
- Department of Radiology (A.F.J.), Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts
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Robotics, automation, active electrode arrays, and new devices for cochlear implantation: A contemporary review. Hear Res 2022; 414:108425. [PMID: 34979455 DOI: 10.1016/j.heares.2021.108425] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 12/16/2021] [Accepted: 12/23/2021] [Indexed: 01/14/2023]
Abstract
In the last two decades, cochlear implant surgery has evolved into a minimally invasive, hearing preservation surgical technique. The devices used during surgery have benefited from technological advances that have allowed modification and possible improvement of the surgical technique. Robotics has recently gained popularity in otology as an effective tool to overcome the surgeon's limitations such as tremor, drift and accurate force control feedback in laboratory testing. Cochlear implantation benefits from robotic assistance in several steps during the surgical procedure: (i) during the approach to the middle ear by automated mastoidectomy and posterior tympanotomy or through a tunnel from the postauricular skin to the middle ear (i.e. direct cochlear access); (ii) a minimally invasive cochleostomy by a robot-assisted drilling tool; (iii) alignment of the correct insertion axis on the basal cochlear turn; (iv) insertion of the electrode array with a motorized insertion tool. In recent years, the development of bone-attached parallel robots and image-guided surgical robotic systems has allowed the first successful cochlear implantation procedures in patients via a single hole drilled tunnel. Several other robotic systems, new materials, sensing technologies applied to the electrodes, and smart devices have been developed, tested in experimental models and finally some have been used in patients with the aim of reducing trauma in cochleostomy, and permitting slow and more accurate insertion of the electrodes. Despite the promising results in laboratory tests in terms of minimal invasiveness, reduced trauma and better hearing preservation, so far, no clinical benefits on residual hearing preservation or better speech performance have been demonstrated. Before these devices can become the standard approach for cochlear implantation, several points still need to be addressed, primarily cost and duration of the procedure. One can hope that improvement in the cost/benefit ratio will expand the technology to every cochlear implantation procedure. Laboratory research and clinical studies on patients should continue with the aim of making intracochlear implant insertion an atraumatic and reversible gesture for total preservation of the inner ear structure and physiology.
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Aljazeeri I, Hamed N, Abdelsamad Y, Sharif T, Al-Momani M, Hagr A. Anatomy-Based Frequency Allocation in Cochlear Implantation: The Importance of Cochlear Coverage. Laryngoscope 2021; 132:2224-2231. [PMID: 34967457 DOI: 10.1002/lary.30004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Revised: 12/09/2021] [Accepted: 12/17/2021] [Indexed: 11/08/2022]
Abstract
OBJECTIVES/HYPOTHESIS This study aimed to compare the predicted anatomy-based frequency allocation of cochlear implant electrodes with the default standard frequencies. STUDY DESIGN Retrospective study. METHODS A retrospective analysis was performed using computed tomography (CT) images of patients who received cochlear implants at a tertiary referral center. Patients were excluded if they had any congenital or acquired cochlear anatomical anomalies. The CT images of the patients were uploaded to the surgical planning software. Two independent reviewers allocated the anatomical parameters of the cochlea. The software then used these parameters to calculate the frequency allocation for each electrode according to the type of electrode and the length of the organ of Corti (OC) in each patient. These anatomy-based frequency allocations were compared with the default frequency settings. MAIN OUTCOME MEASURE Frequency-to-place mismatch in semitones. RESULTS A total of 169 implanted ears in 102 patients were included in this study. The readings of the two reviewers were homogenous, with a Cronbach's alpha of 0.98. The mean anatomy-based frequency allocation was 487.3 ± 202.9 Hz in electrode 1; 9,298.6 ± 490.6 Hz in electrode 12. The anatomy-based frequency allocations were found to be significantly higher than the frequencies of the default frequencies for each corresponding electrode (one-sample t-test, P < .001). The frequency-to-place mismatch was negatively correlated with cochlear coverage and positively correlated with the cochlear duct length (Pearson correlation > 0.65, P < .003). CONCLUSIONS The anatomy-based frequency allocation of each electrode is significantly different from the default frequency setting. This frequency-to-place mismatch was affected mainly by the cochlear coverage. LEVEL OF EVIDENCE 3 Laryngoscope, 2021.
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Affiliation(s)
- Isra Aljazeeri
- King Abdullah Ear Specialist Center (KAESC), College of Medicine, King Saud University Medical City (KSUMC), King Saud University, Riyadh, Saudi Arabia.,Aljaber Ophthalmology and Otolaryngology Specialized Hospital, Ministry of Health, Ahsa, Saudi Arabia
| | - Nezar Hamed
- King Abdullah Ear Specialist Center (KAESC), College of Medicine, King Saud University Medical City (KSUMC), King Saud University, Riyadh, Saudi Arabia
| | | | - Tahir Sharif
- Research Department, MED-EL GmbH, Riyadh, Saudi Arabia
| | - Murad Al-Momani
- ENT Department, College of Medicine, King Saud University, Riyadh, Saudi Arabia
| | - Abdulrahman Hagr
- King Abdullah Ear Specialist Center (KAESC), College of Medicine, King Saud University Medical City (KSUMC), King Saud University, Riyadh, Saudi Arabia
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Atturo F, Portanova G, Russo FY, Seta DD, Mariani L, Borel S, Greco A, Mosnier I, Mancini P. Cochlear implant in immune mediated inner ear diseases: Impedance variations and clinical outcomes. Cochlear Implants Int 2021; 23:70-79. [PMID: 34844527 DOI: 10.1080/14670100.2021.1992149] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
OBJECTIVE Immune-mediated inner ear disease (IMIED) might cause severe/profound hearing loss and these patients are considered ideal candidates to cochlear implant (CI) surgery. The aim of the study was to evaluate impedance changes over time. METHOD The Study Group (SG) was composed of CI IMIED patients (31 ears) and a Control Group (CG) of CI patients with hearing loss not related to their immune system (31 ears). Audiological performance and impedance values were measured and compared amongst groups at 3, 6, 12 and 18 months following the fitting sessions. RESULTS Speech perception was significantly better for SG in word and sentence recognition in quiet. Impedance values were, on average, significantly higher for apical and middle electrode segments in SG compared to CG at the 3- month follow-up and were maintained over time. Additionally, a subset of SG patients (active patients) experienced significantly greater impedance fluctuation corresponding to clinical symptom reactivation. CONCLUSION IMIED patients achieve good audiological performance. However, the relapsing inflammation could change the inner ear environment, causing impedance fluctuations and, consequently, more frequent CI fittings. Additionally, impedance evaluation could be utilized as an early warning sign of IMIED recurrence and as an aid to therapeutic decision-making.
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Affiliation(s)
- Francesca Atturo
- Department of Sense Organs, "Sapienza" University of Rome, Rome, Italy
| | - Ginevra Portanova
- Department of Sense Organs, "Sapienza" University of Rome, Rome, Italy
| | | | - Daniele De Seta
- Unit of Otorhinolaryngology, Department of Surgery, University of Cagliari, Cagliari, Italy
| | - Laura Mariani
- Department of Sense Organs, "Sapienza" University of Rome, Rome, Italy
| | - Stephanie Borel
- Service ORL, Otologie, Implants Auditifs et Chirurgie de la Base du Crâne, AP-HP, GHU Pitié-Salpêtrière, Paris, France
| | - Antonio Greco
- Department of Sense Organs, "Sapienza" University of Rome, Rome, Italy
| | - Isabelle Mosnier
- Service ORL, Otologie, Implants Auditifs et Chirurgie de la Base du Crâne, AP-HP, GHU Pitié-Salpêtrière, Paris, France
| | - Patrizia Mancini
- Department of Sense Organs, "Sapienza" University of Rome, Rome, Italy
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Relevant temporal bone anatomy for robotic cochlear implantation: An updated terminology combined with anatomical and clinical terms. TRANSLATIONAL RESEARCH IN ANATOMY 2021. [DOI: 10.1016/j.tria.2021.100138] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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13
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Torres R, Daoudi H, Lahlou G, Sterkers O, Ferrary E, Mosnier I, Nguyen Y. Restoration of High Frequency Auditory Perception After Robot-Assisted or Manual Cochlear Implantation in Profoundly Deaf Adults Improves Speech Recognition. Front Surg 2021; 8:729736. [PMID: 34568420 PMCID: PMC8461256 DOI: 10.3389/fsurg.2021.729736] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 08/17/2021] [Indexed: 11/13/2022] Open
Abstract
Background and Purpose: Robot-assisted cochlear implantation has recently been implemented in clinical practice; however, its effect on hearing outcomes is unknown. The aim of this preliminary study was to evaluate hearing performance 1 year post-implantation whether the electrode array was inserted manually or assisted by a robot. Methods: Forty-two profoundly deaf adults were implanted either manually (n = 21) or assisted by a robot (RobOtol®, Collin, Bagneux, France) with three different electrode array types. Participants were paired by age, and electrode array type. The scalar position of the electrode array in the cochlea was assessed by 3D reconstruction from the pre- and post-implantation computed tomography. Pure-tone audiometry and speech perception in silence (percentage of disyllabic words at 60 dB) were tested on the implanted ear 1 year post-implantation in free-field conditions. The pure-tone average was calculated at 250–500–750 Hz, 500–1,000–2,000–3,000 Hz, and 3,000–4,000–8,000 Hz for low, mid, and high frequencies, respectively. Results: One year after cochlear implantation, restoration of the high-frequency thresholds was associated with better speech perception in silence, but not with low or mid frequencies (p < 0.0001; Adjusted R2 = 0.64, polynomial non-linear regression). Although array translocation was similar using either technique, the number of translocated electrodes was lower when the electrode arrays had been inserted with the assistance of the robot compared with manual insertion (p = 0.018; Fisher's exact test). Conclusion: The restoration of high-frequency thresholds (3,000–4,000–8,000 Hz) by cochlear implantation was associated with good speech perception in silence. The numbers of translocated electrodes were reduced after a robot-assisted insertion.
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Affiliation(s)
- Renato Torres
- Unité Fonctionnelle Implants Auditifs, Service Oto-Rhino-Laryngologie, AP-HP/Sorbonne Université, Paris, France.,Centre de Recherche en Audiologie Adulte, GHU Pitié-Salpêtrière/Fondation Pour l'Audition, AP-HP, Paris, France.,Technologies et Thérapie Génique Pour la Surdité, Institut de l'Audition, Institut Pasteur, INSERM, Paris, France.,Departamento de Ciencias Fisiológicas, Facultad de Medicina, Universidad Nacional de San Agustín de Arequipa, Arequipa, Peru
| | - Hannah Daoudi
- Unité Fonctionnelle Implants Auditifs, Service Oto-Rhino-Laryngologie, AP-HP/Sorbonne Université, Paris, France.,Centre de Recherche en Audiologie Adulte, GHU Pitié-Salpêtrière/Fondation Pour l'Audition, AP-HP, Paris, France.,Technologies et Thérapie Génique Pour la Surdité, Institut de l'Audition, Institut Pasteur, INSERM, Paris, France
| | - Ghizlene Lahlou
- Unité Fonctionnelle Implants Auditifs, Service Oto-Rhino-Laryngologie, AP-HP/Sorbonne Université, Paris, France.,Centre de Recherche en Audiologie Adulte, GHU Pitié-Salpêtrière/Fondation Pour l'Audition, AP-HP, Paris, France.,Technologies et Thérapie Génique Pour la Surdité, Institut de l'Audition, Institut Pasteur, INSERM, Paris, France
| | - Olivier Sterkers
- Unité Fonctionnelle Implants Auditifs, Service Oto-Rhino-Laryngologie, AP-HP/Sorbonne Université, Paris, France.,Centre de Recherche en Audiologie Adulte, GHU Pitié-Salpêtrière/Fondation Pour l'Audition, AP-HP, Paris, France.,Technologies et Thérapie Génique Pour la Surdité, Institut de l'Audition, Institut Pasteur, INSERM, Paris, France
| | - Evelyne Ferrary
- Unité Fonctionnelle Implants Auditifs, Service Oto-Rhino-Laryngologie, AP-HP/Sorbonne Université, Paris, France.,Centre de Recherche en Audiologie Adulte, GHU Pitié-Salpêtrière/Fondation Pour l'Audition, AP-HP, Paris, France.,Technologies et Thérapie Génique Pour la Surdité, Institut de l'Audition, Institut Pasteur, INSERM, Paris, France
| | - Isabelle Mosnier
- Unité Fonctionnelle Implants Auditifs, Service Oto-Rhino-Laryngologie, AP-HP/Sorbonne Université, Paris, France.,Centre de Recherche en Audiologie Adulte, GHU Pitié-Salpêtrière/Fondation Pour l'Audition, AP-HP, Paris, France.,Technologies et Thérapie Génique Pour la Surdité, Institut de l'Audition, Institut Pasteur, INSERM, Paris, France
| | - Yann Nguyen
- Unité Fonctionnelle Implants Auditifs, Service Oto-Rhino-Laryngologie, AP-HP/Sorbonne Université, Paris, France.,Centre de Recherche en Audiologie Adulte, GHU Pitié-Salpêtrière/Fondation Pour l'Audition, AP-HP, Paris, France.,Technologies et Thérapie Génique Pour la Surdité, Institut de l'Audition, Institut Pasteur, INSERM, Paris, France
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Schendzielorz P, Ilgen L, Müller-Graff FT, Noyalet L, Völker J, Taeger J, Hagen R, Neun T, Zabler S, Althoff D, Rak K. Precise evaluation of the postoperative cochlear duct length by flat-panel volume computed tomography - Application of secondary reconstructions. Cochlear Implants Int 2021; 23:32-42. [PMID: 34519256 DOI: 10.1080/14670100.2021.1973208] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
OBJECTIVE There is still a lack in precise postoperative evaluation of the cochlea because of strong artifacts. This study aimed to improve accuracy of postoperative two-turn (2TL) and cochlear duct length (CDL) measurements by applying flat-panel volume computed tomography (fpVCT), secondary reconstruction (fpVCTSECO) and three-dimensional curved multiplanar reconstruction. METHODS First, 10 temporal bone specimens with or without electrode were measured in multi-slice computed tomography (MSCT), fpVCT and fpVCTSECO and compared to high-resolution micro-CT scans. Later, pre- and postoperative scans of 10 patients were analyzed in a clinical setting. RESULTS Concerning 2TL, no statistically significant difference was observed between implanted fpVCTSECO and nonimplanted micro-CT in 10 temporal bone specimens. In contrast, there was a significant discrepancy for CDL (difference: -0.7 mm, P = 0.004). Nevertheless, there were no clinically unacceptable errors (±1.5 mm). These results could be confirmed in a clinical setting. Using fpVCTSECO, CDL was slightly underestimated postoperatively (difference: -0.5 mm, P = 0.002) but without any clinically unacceptable errors. CONCLUSION fpVCTSECO can be successfully applied for a precise measurement of the cochlear lengths pre- and postoperatively. However, users must be aware of a slight systematic underestimation of CDL postoperatively. These results may help to refine electrode selection and frequency mapping.
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Affiliation(s)
- Philipp Schendzielorz
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery and the Comprehensive Hearing Center, University of Würzburg, Würzburg, Germany
| | - Lukas Ilgen
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery and the Comprehensive Hearing Center, University of Würzburg, Würzburg, Germany
| | - Franz-Tassilo Müller-Graff
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery and the Comprehensive Hearing Center, University of Würzburg, Würzburg, Germany
| | - Laurent Noyalet
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery and the Comprehensive Hearing Center, University of Würzburg, Würzburg, Germany
| | - Johannes Völker
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery and the Comprehensive Hearing Center, University of Würzburg, Würzburg, Germany
| | - Johannes Taeger
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery and the Comprehensive Hearing Center, University of Würzburg, Würzburg, Germany
| | - Rudolf Hagen
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery and the Comprehensive Hearing Center, University of Würzburg, Würzburg, Germany
| | - Tilmann Neun
- Department of Diagnostic and Interventional Neuroradiology, University of Würzburg, Würzburg, Germany
| | - Simon Zabler
- Department of X-ray Microscopy, University of Würzburg, Würzburg, Germany
| | - Daniel Althoff
- Fraunhofer Development Center for X-ray Technology, Würzburg, Germany
| | - Kristen Rak
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery and the Comprehensive Hearing Center, University of Würzburg, Würzburg, Germany
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15
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Three-Dimensional Modeling and Measurement of the Human Cochlear Hook Region: Considerations for Tonotopic Mapping. Otol Neurotol 2021; 42:e658-e665. [PMID: 34111048 DOI: 10.1097/mao.0000000000003065] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
HYPOTHESIS Measuring the length of the basilar membrane (BM) in the cochlear hook region will result in improved accuracy of cochlear duct length (CDL) measurements. BACKGROUND Cochlear implant pitch mapping is generally performed in a patient independent approach, which has been shown to result in place-pitch mismatches. In order to customize cochlear implant pitch maps, accurate CDL measurements must be obtained. CDL measurements generally begin at the center of the round window (RW) and ignore the basal-most portion of the BM in the hook region. Measuring the size and morphology of the BM in the hook region can improve CDL measurements and our understanding of cochlear tonotopy. METHODS Ten cadaveric human cochleae underwent synchrotron radiation phase-contrast imaging. The length of the BM through the hook region and CDL were measured. Two different CDL measurements were obtained for each sample, with starting points at the center of the RW (CDLRW) and the basal-most tip of the BM (CDLHR). Regression analysis was performed to relate CDLRW to CDLHR. A three-dimensional polynomial model was determined to describe the average BM hook region morphology. RESULTS The mean CDLRW value was 33.03 ± 1.62 mm, and the mean CDLHR value was 34.68 ± 1.72 mm. The following relationship was determined between CDLRW and CDLHR: CDLHR = 1.06(CDLRW)-0.26 (R2 = 0.99). CONCLUSION The length and morphology of the hook region was determined. Current measurements underestimate CDL in the hook region and can be corrected using the results herein.
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Li H, Schart-Moren N, Rajan G, Shaw J, Rohani SA, Atturo F, Ladak HM, Rask-Andersen H, Agrawal S. Vestibular Organ and Cochlear Implantation-A Synchrotron and Micro-CT Study. Front Neurol 2021; 12:663722. [PMID: 33897611 PMCID: PMC8058461 DOI: 10.3389/fneur.2021.663722] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 03/15/2021] [Indexed: 11/13/2022] Open
Abstract
Background: Reports vary on the incidence of vestibular dysfunction and dizziness in patients following cochlear implantation (CI). Disequilibrium may be caused by surgery at the cochlear base, leading to functional disturbances of the vestibular receptors and endolymphatic duct system (EDS) which are located nearby. Here, we analyzed the three-dimensional (3D) anatomy of this region, aiming to optimize surgical approaches to limit damage to the vestibular organ. Material and Methods: A total of 22 fresh-frozen human temporal bones underwent synchrotron radiation phase-contrast imaging (SR-PCI). One temporal bone underwent micro-computed tomography (micro-CT) after fixation and staining with Lugol's iodine solution (I2KI) to increase tissue contrast. We used volume-rendering software to create 3D reconstructions and tissue segmentation that allowed precise assessment of anatomical relationships and topography. Macerated human ears belonging to the Uppsala collection were also used. Drilling and insertion of CI electrodes was performed with metric analyses of different trajectories. Results and Conclusions: SR-PCI and micro-CT imaging demonstrated the complex 3D anatomy of the basal region of the human cochlea, vestibular apparatus, and EDS. Drilling of a cochleostomy may disturb vestibular organ function by injuring the endolymphatic space and disrupting fluid barriers. The saccule is at particular risk due to its proximity to the surgical area and may explain immediate and long-term post-operative vertigo. Round window insertion may be less traumatic to the inner ear, however it may affect the vestibular receptors.
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Affiliation(s)
- Hao Li
- Department of Surgical Sciences, Otorhinolaryngology and Head and Neck Surgery, Uppsala University, Uppsala, Sweden
| | - Nadine Schart-Moren
- Department of Surgical Sciences, Otorhinolaryngology and Head and Neck Surgery, Uppsala University, Uppsala, Sweden
- Section of Otolaryngology, Head and Neck Surgery, Uppsala University Hospital, Uppsala, Sweden
| | - Gunesh Rajan
- Department of Otolaryngology, Head & Neck Surgery, Luzerner Kantonsspital, Lucerne, Switzerland
- Department of Otolaryngology, Head & Neck Surgery, Division of Surgery, Medical School, University of Western Australia, Perth, WA, Australia
| | - Jeremy Shaw
- Centre for Microscopy, Characterization and Analysis, Perth, WA, Australia
| | - Seyed Alireza Rohani
- Department of Otolaryngology-Head and Neck Surgery, Western University, London, ON, Canada
| | - Francesca Atturo
- Department of Otolaryngology, University of Sapienza, Rome, Italy
| | - Hanif M. Ladak
- Department of Otolaryngology-Head and Neck Surgery, Western University, London, ON, Canada
- Department of Medical Biophysics and Department of Electrical and Computer Engineering, Western University, London, ON, Canada
| | - Helge Rask-Andersen
- Department of Surgical Sciences, Otorhinolaryngology and Head and Neck Surgery, Uppsala University, Uppsala, Sweden
| | - Sumit Agrawal
- Department of Otolaryngology-Head and Neck Surgery, Western University, London, ON, Canada
- Department of Medical Biophysics and Department of Electrical and Computer Engineering, Western University, London, ON, Canada
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17
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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.
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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
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Rak K, Ilgen L, Taeger J, Schendzielorz P, Voelker J, Kaulitz S, Müller-Graff FT, Kurz A, Neun T, Hagen R. Influence of cochlear parameters on the current practice in cochlear implantation : Development of a concept for personalized medicine. HNO 2021; 69:24-30. [PMID: 33459799 DOI: 10.1007/s00106-020-00969-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/11/2020] [Indexed: 11/26/2022]
Abstract
Since the introduction of cochlear implants into clinical routine, the interest in measuring cochlear parameters, particularly the cochlear duct length (CDL) has increased, since these can have an influence on the correct selection of the electrode. On the one hand, coverage of an optimal frequency band is relevant for a good audiological result, and on the other hand, cochlear trauma due to too deep insertion or displacement of the electrode must be avoided. Cochlear implants stimulate the spiral ganglion cells (SGC). The number of SGC and particularly their distribution can also have an influence on the function of a cochlear implant. In addition, the frequency assignment of each electrode contact can play a decisive role in the postoperative success, since the frequency distribution of the human cochlea with varying CDL shows substantial interindividual differences. The aim of this work is to provide an overview of the methods used to determine the cochlear parameters as well as of relevant studies on the CDL, the number and distribution of SGZ, and the frequency assignment of electrode contacts. Based on this, a concept for individualized cochlear implantation will be presented. In summary, this work should help to promote individualized medicine in the field of cochlear implants in the future, in order to overcome current limitations and optimize audiological outcomes.
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Affiliation(s)
- K Rak
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery and the Comprehensive Hearing Center, University of Würzburg, Josef-Schneider-Straße 11, 97080, Würzburg, Germany.
| | - L Ilgen
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery and the Comprehensive Hearing Center, University of Würzburg, Josef-Schneider-Straße 11, 97080, Würzburg, Germany
| | - J Taeger
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery and the Comprehensive Hearing Center, University of Würzburg, Josef-Schneider-Straße 11, 97080, Würzburg, Germany
| | - P Schendzielorz
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery and the Comprehensive Hearing Center, University of Würzburg, Josef-Schneider-Straße 11, 97080, Würzburg, Germany
| | - J Voelker
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery and the Comprehensive Hearing Center, University of Würzburg, Josef-Schneider-Straße 11, 97080, Würzburg, Germany
| | - S Kaulitz
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery and the Comprehensive Hearing Center, University of Würzburg, Josef-Schneider-Straße 11, 97080, Würzburg, Germany
| | - F-T Müller-Graff
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery and the Comprehensive Hearing Center, University of Würzburg, Josef-Schneider-Straße 11, 97080, Würzburg, Germany
| | - A Kurz
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery and the Comprehensive Hearing Center, University of Würzburg, Josef-Schneider-Straße 11, 97080, Würzburg, Germany
| | - T Neun
- Institute for Diagnostic and Interventional Neuroradiology, University Hospital Würzburg, Würzburg, Germany
| | - R Hagen
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery and the Comprehensive Hearing Center, University of Würzburg, Josef-Schneider-Straße 11, 97080, Würzburg, Germany
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[Influence of cochlear parameters on the current practice in cochlear implantation : Development of a concept for personalized medicine. German version]. HNO 2020; 69:943-951. [PMID: 33315129 DOI: 10.1007/s00106-020-00968-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/21/2020] [Indexed: 10/22/2022]
Abstract
Since the introduction of cochlear implants into clinical routine, the interest in measuring cochlear parameters, particularly the cochlear duct length (CDL) has increased, since these can have an influence on the correct selection of the electrode. On the one hand, coverage of an optimal frequency band is relevant for a good audiological result, and on the other hand, cochlear trauma due to too deep insertion or displacement of the electrode must be avoided. Cochlear implants stimulate the spiral ganglion cells (SGC). The number of SGC and particularly their distribution can also have an influence on the function of a cochlear implant. In addition, the frequency assignment of each electrode contact can play a decisive role in the postoperative success, since the frequency distribution of the human cochlea with varying CDL shows substantial interindividual differences. The aim of this work is to provide an overview of the methods used to determine the cochlear parameters as well as of relevant studies on the CDL, the number and distribution of SGZ, and the frequency assignment of electrode contacts. Based on this, a concept for individualized cochlear implantation will be presented. In summary, this work should help to promote individualized medicine in the field of cochlear implants in the future, in order to overcome current limitations and optimize audiological outcomes.
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20
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Jwair S, Prins A, Wegner I, Stokroos RJ, Versnel H, Thomeer HGXM. Scalar Translocation Comparison Between Lateral Wall and Perimodiolar Cochlear Implant Arrays - A Meta-Analysis. Laryngoscope 2020; 131:1358-1368. [PMID: 33159469 PMCID: PMC8246990 DOI: 10.1002/lary.29224] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 10/15/2020] [Accepted: 10/16/2020] [Indexed: 12/15/2022]
Abstract
Objectives/Hypothesis Two types of electrode arrays for cochlear implants (CIs) are distinguished: lateral wall and perimodiolar. Scalar translocation of the array can lead to intracochlear trauma by penetrating from the scala tympani into the scala vestibuli or scala media, potentially negatively affecting hearing performance of CI users. This systematic review compares the lateral wall and perimodiolar arrays with respect to scalar translocation. Study Design Systematic review. Methods PubMed, Embase, and Cochrane databases were reviewed for studies published within the last 11 years. No other limitations were set. All studies with original data that evaluated the occurrence of scalar translocation or tip fold‐over (TF) with postoperative computed tomography (CT) following primary cochlear implantation in bilateral sensorineuronal hearing loss patients were considered to be eligible. Data were extracted independently by two reviewers. Results We included 33 studies, of which none were randomized controlled trials. Meta‐analysis of five cohort studies comparing scalar translocation between lateral wall and perimodiolar arrays showed that lateral wall arrays have significantly lower translocation rates (7% vs. 43%; pooled odds ratio = 0.12). Translocation was negatively associated with speech perception scores (weighted mean 41% vs. 55%). Tip fold‐over of the array was more frequent with perimodiolar arrays (X2 = 6.8, P < .01). Conclusions Scalar translocation and tip fold‐overs occurred more frequently with perimodiolar arrays than with lateral wall arrays. In addition, translocation of the array negatively affects hearing with the cochlear implant. Therefore, if one aims to minimize clinically relevant intracochlear trauma, lateral wall arrays would be the preferred option for cochlear implantation. Laryngoscope, 131:1358–1368, 2021
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Affiliation(s)
- Saad Jwair
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands.,UMC Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
| | - Adrianus Prins
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Inge Wegner
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Robert J Stokroos
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht University, 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, 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, Utrecht, The Netherlands.,UMC Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
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Nguy PL, Saidha S, Jay A, Jeffrey Kim H, Hoa M. Radiologic anatomy of the round window relevant to cochlear implantation and inner ear drug delivery. World J Otorhinolaryngol Head Neck Surg 2020; 7:9-16. [PMID: 33474538 PMCID: PMC7801246 DOI: 10.1016/j.wjorl.2018.12.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 11/03/2018] [Accepted: 12/03/2018] [Indexed: 11/28/2022] Open
Abstract
Objective To determine anatomic relationships and variation of the round window membrane to bony surgical landmarks on computed tomography. Study design Retrospective imaging review. Methods 100 temporal bone images were evaluated. Direct measurements were obtained for membrane position. Vector distances and angulation from umbo and bony annulus were calculated from image viewer software coordinates. Results The angle of round window membrane at junction with cochlear basal turn was (42.1 ± 8.6)°. The membrane's position relative to plane of the facial nerve through facial recess was (14.7 ± 5.2)° posterior from a reference line drawn through facial recess to carotid canal. Regarding transtympanic drug delivery, the round window membrane was directed 4.1 mm superiorly from the inferior annulus and 5.4 mm anteriorly from the posterior annulus. The round window membrane on average was angled superiorly from the inferior annulus (77.1 ± 27.9)° and slightly anteriorly from the posterior annulus (19.1 ± 11.1°). The mean distance of round window membrane from umbo was 4 mm and posteriorly rotated 30° clockwise from a perpendicular drawn from umbo to inferior annulus towards posterior annulus. Together, these measurements approximate the round window membrane in the tympanic membrane's posteroinferior quadrant. Conclusions These radiologic measurements demonstrate normal variations seen in round window anatomy relative to facial recess approach and bony tympanic annulus, providing a baseline to assess round window insertion for cochlear implantation and outlines anatomic factors affecting transtympanic drug delivery.
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Affiliation(s)
- Peter L Nguy
- Department of Otolaryngology-Head and Neck Surgery, Georgetown University Medical Center, Washington DC, USA
| | - Sheela Saidha
- Department of Otolaryngology, University of Rochester Medical Center, Rochester, NY, USA
| | - Ann Jay
- Department of Radiology, Georgetown University Medical Center, Washington DC, USA
| | - H Jeffrey Kim
- Department of Otolaryngology-Head and Neck Surgery, Georgetown University Medical Center, Washington DC, USA
| | - Michael Hoa
- Department of Otolaryngology-Head and Neck Surgery, Georgetown University Medical Center, Washington DC, USA
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22
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Anschuetz L, Alicandri-Ciufelli M, Wimmer W, Bonali M, Caversaccio M, Presutti L. The endoscopic anatomy of the cochlear hook region and fustis: surgical implications. ACTA ACUST UNITED AC 2020; 39:353-357. [PMID: 31708582 PMCID: PMC6843579 DOI: 10.14639/0392-100x-2388] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Accepted: 06/13/2019] [Indexed: 11/23/2022]
Abstract
The cochlear hook region can be considered as the interface between the middle and inner ear. The identification of surgically-relevant endoscopic landmarks of this anatomical entity and assessment of their clinical value is still lacking in the literature. Procedures like cholesteatoma surgery and minimal invasive endoscopic approaches to the lateral skull base may particularly benefit from these considerations. We hypothesize that the spatial orientation of anatomical landmarks in the cochlear hook can be expressed in angles and are reproducibly identifiable by transcanal otoendoscopy. Therefore, endoscopic dissection of the cochlear hook region was performed in 32 temporal bone specimens. Topographic anatomy was documented and analysed. We performed computed tomography of 28 specimens to assess the region in three-dimensional reconstructions. The mean angle between the round window and the basal scala tympani was assessed 25.9° in endoscopic and 28.2° in three-dimensionally reconstructed models. The fustis was recognised as a reliable landmark for the basal turn. A mean angle of 155.4° to the basal scala tympani was assessed. A slight bulging without obstruction of the basal turn was observed in 5 cases. The utility of the revealed anatomical details was assessed in minimal invasive endoscopic lateral skull base approaches. In conclusion, we described the angles between anatomical landmarks of the cochlear hook region. Moreover, the angle as recorded through an endoscope was found to be reliable compared to three-dimensional reconstructions from computed tomography.
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Affiliation(s)
- L Anschuetz
- Department of Otolaryngology Head and Neck Surgery, University Hospital of Modena, Italy.,Department of Otolaryngology Head and Neck Surgery, Inselspital, University Hospital and University of Bern, Switzerland
| | - M Alicandri-Ciufelli
- Department of Otolaryngology Head and Neck Surgery, University Hospital of Modena, Italy.,Neurosurgery Department, New Civil Hospital Sant'Agostino-Estense, Baggiovara (MO), Italy
| | - W Wimmer
- Department of Otolaryngology Head and Neck Surgery, Inselspital, University Hospital and University of Bern, Switzerland.,Artificial Hearing Research, ARTORG Center for Biomedical Engineering, University of Bern, Switzerland
| | - M Bonali
- Department of Otolaryngology Head and Neck Surgery, University Hospital of Modena, Italy
| | - M Caversaccio
- Department of Otolaryngology Head and Neck Surgery, Inselspital, University Hospital and University of Bern, Switzerland.,Artificial Hearing Research, ARTORG Center for Biomedical Engineering, University of Bern, Switzerland
| | - L Presutti
- Department of Otolaryngology Head and Neck Surgery, University Hospital of Modena, Italy
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Endoscopic approach to the round window through posterior tympanotomy for cochlear implantation in children: A study on feasibility. Int J Pediatr Otorhinolaryngol 2020; 129:109781. [PMID: 31756660 DOI: 10.1016/j.ijporl.2019.109781] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 11/11/2019] [Accepted: 11/12/2019] [Indexed: 11/22/2022]
Abstract
OBJECTIVE To demonstrate the feasibility of rigid endoscopy through posterior tympanotomy, which provides both a view of the round window and direction of the scala tympani in children. METHODS After a standard mini-invasive surgical approach with postauricular access and transmastoid posterior tympanotomy of 2 mm, a 0°, 1.9 mm diameter and 11 cm long endoscope is positioned in proximity of the upper part of the posterior tympanotomy to obtain a panoramic view of the inferior part of the medial wall of the tympanic cavity. Surgical complications and changes in hearing threshold were analyzed. RESULTS Eight children were submitted to cochlear implantation with endoscopic assistance through posterior tympanotomy. Complete visualization of the round window niche was possible in every ear. No complications related to the procedure were observed. Preoperative threshold was preserved in 9 of 10 ears. CONCLUSIONS Direct endoscopic view through the posterior tympanotomy allows visualization of the entire round window niche as well as the angle of introduction of the multi-electrode array along the direction of the scala tympani.
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Abstract
Auditory processing in the cochlea depends on the integrity of the mechanosensory hair cells. Over a lifetime, hearing loss can be acquired from numerous etiologies such as exposure to excessive noise, the use of ototoxic medications, bacterial or viral ear infections, head injuries, and the aging process. Loss of sensory hair cells is a common pathological feature of the varieties of acquired hearing loss. Additionally, the inner hair cell synapse can be damaged by mild insults. Therefore, surface preparations of cochlear epithelia, in combination with immunolabeling techniques and confocal imagery, are a very useful tool for the investigation of cochlear pathologies, including losses of ribbon synapses and sensory hair cells, changes in protein levels in hair cells and supporting cells, hair cell regeneration, and determination of report gene expression (i.e., GFP) for verification of successful transduction and identification of transduced cell types. The cochlea, a bony spiral-shaped structure in the inner ear, holds the auditory sensory end organ, the organ of Corti (OC). Sensory hair cells and surrounding supporting cells in the OC are contained in the cochlear duct and rest on the basilar membrane, organized in a tonotopic fashion with high-frequency detection occurring in the base and low-frequency in the apex. With the availability of molecular and genetic information and the ability to manipulate genes by knockout and knock-in techniques, mice have been widely used in biological research, including in hearing science. However, the adult mouse cochlea is miniscule, and the cochlear epithelium is encapsulated in a bony labyrinth, making microdissection difficult. Although dissection techniques have been developed and used in many laboratories, this modified microdissection method using cell and tissue adhesive is easier and more convenient. It can be used in all types of adult mouse cochleae following decalcification.
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Affiliation(s)
- Qiao-Jun Fang
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina; MOE Key Laboratory of Developmental Genes and Human Disease, Institute of Life Sciences, Southeast University
| | - Fan Wu
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina
| | - Renjie Chai
- MOE Key Laboratory of Developmental Genes and Human Disease, Institute of Life Sciences, Southeast University
| | - Su-Hua Sha
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina;
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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.
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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
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Badr A, Shabana Y, Mokbel K, Elsharabasy A, Ghonim M, Sanna M. Atraumatic Scala Tympani Cochleostomy; Resolution of the Dilemma. J Int Adv Otol 2019; 14:190-196. [PMID: 30100542 DOI: 10.5152/iao.2018.4974] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVES While an accurate placement in cochleostomy is critical to ensure appropriate insertion of the cochlear implant (CI) electrode into the scala tympani (ST), the choice of preferred cochleostomy sites widely varied among experienced surgeons. We present a novel technique for precise yet readily applicable localization of the optimum site for performing ST cochleostomy. MATERIAL AND METHODS Twenty fresh frozen temporal bones were dissected using the mastoidectomy-posterior tympanotomy approach. Based on the facial nerve and the margins of the round window membrane (RWM), the cochleostomy site was chosen to insert the electrode into the ST while preserving the surrounding intracochlear structures. RESULTS There is a limited safe area suitable for the ST implantation in the area inferior and anterior to the RWM. There is a higher risk of scala vestibuli (SV) insertion anterior to that area. Posterior to that area, the cochlear aqueduct (CA) and inferior cochlear vein (ICV) are liable for the injury. CONCLUSION For atraumatic CI, precise and easy localization of the site of cochleostomy play a pivotal role in preserving intracochlear structures. Accurate setting of the vertical and horizontal orientations is mandatory before choosing the site of cochleostomy. The facial nerve and the margins of the RWM offer a very helpful clue for such localization; meanwhile, it is readily identifiable in the surgical field.
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Affiliation(s)
- Ahmad Badr
- Department of ENT, Head and Neck Surgery, Mansoura University School of Medicine, Mansoura City, Egypt
| | - Yousef Shabana
- Department of ENT, Head and Neck Surgery, Mansoura University School of Medicine, Mansoura City, Egypt
| | - Khaled Mokbel
- Department of ENT, Head and Neck Surgery, Mansoura University School of Medicine, Mansoura City, Egypt
| | - Ayman Elsharabasy
- Department of ENT, Head and Neck Surgery, Mansoura University School of Medicine, Mansoura City, Egypt
| | - Mohamed Ghonim
- Department of ENT, Head and Neck Surgery, Mansoura University School of Medicine, Mansoura City, Egypt
| | - Mario Sanna
- Department of Otology and Skull Base Surgery, Gruppo Otologico, Piacenza, Rome, Italy
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High-resolution Imaging of the Human Cochlea through the Round Window by means of Optical Coherence Tomography. Sci Rep 2019; 9:14271. [PMID: 31582808 PMCID: PMC6776619 DOI: 10.1038/s41598-019-50727-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 09/16/2019] [Indexed: 12/12/2022] Open
Abstract
The human cochlea is deeply embedded in the temporal bone and surrounded by a thick otic capsule, rendering its internal structure inaccessible for direct visualization. Clinical imaging techniques fall short of their resolution for imaging of the intracochlear structures with sufficient detail. As a result, there is a lack of knowledge concerning best practice for intracochlear therapy placement, such as cochlear implantation. In the past decades, optical coherence tomography (OCT) has proven valuable for non-invasive, high-resolution, cross-sectional imaging of tissue microstructure in various fields of medicine, including ophthalmology, cardiology and dermatology. There is an upcoming interest for OCT imaging of the cochlea, which so far was mostly carried out in small animals. In this temporal bone study, we focused on high-resolution imaging of the human cochlea. The cochlea was approached through mastoidectomy and posterior tympanotomy, both standard surgical procedures. A commercially available spectral-domain OCT imaging system was used to obtain high-resolution images of the cochlear hook region through the intact round window membrane in four cadaveric human temporal bones. We discuss the qualitative and quantitative characteristics of intracochlear structures on OCT images and their importance for cochlear implant surgery.
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Rau TS, Kreul D, Lexow J, Hügl S, Zuniga MG, Lenarz T, Majdani O. Characterizing the size of the target region for atraumatic opening of the cochlea through the facial recess. Comput Med Imaging Graph 2019; 77:101655. [DOI: 10.1016/j.compmedimag.2019.101655] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 07/05/2019] [Accepted: 08/19/2019] [Indexed: 11/26/2022]
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Effects of Various Trajectories on Tissue Preservation in Cochlear Implant Surgery: A Micro-Computed Tomography and Synchrotron Radiation Phase-Contrast Imaging Study. Ear Hear 2019; 40:393-400. [PMID: 29952804 DOI: 10.1097/aud.0000000000000624] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES The purpose of this study was to evaluate the three-dimensional (3D) anatomy and potential damage to the hook region of the human cochlea following various trajectories at cochlear implantation (CI). The goal was to determine which of the approaches can avoid lesions to the soft tissues, including the basilar membrane and its suspension to the lateral wall. Currently, there is increased emphasis on conservation of inner ear structures, even in nonhearing preservation CI surgery. DESIGN Micro-computed tomography and various CI approaches were made in an archival collection of macerated and freshly fixed human temporal bones. Furthermore, synchrotron radiation phase-contrast imaging was used to reproduce the soft tissues. The 3D anatomy was investigated using bony and soft tissue algorithms, and influences on inner ear structures were examined. RESULTS Micro-computed tomography with 3D rendering demonstrated the topography of the round window (RW) and osseous spiral laminae, while synchrotron imaging allowed reproduction of soft tissues such as the basilar membrane and its suspension around the RW membrane. Anterior cochleostomies and anteroinferior cochleostomies invariably damaged the intracochlear soft tissues while inferior cochleostomies sporadically left inner ear structures unaffected. CONCLUSIONS Results suggest that cochleostomy approaches often traumatize the soft tissues at the hook region at CI surgery. For optimal structural preservation, the RW approach is, therefore, recommended.
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30
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Mei X, Atturo F, Wadin K, Larsson S, Agrawal S, Ladak HM, Li H, Rask-Andersen H. Human inner ear blood supply revisited: the Uppsala collection of temporal bone-an international resource of education and collaboration. Ups J Med Sci 2018; 123:131-142. [PMID: 30204028 PMCID: PMC6198224 DOI: 10.1080/03009734.2018.1492654] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND The Uppsala collection of human temporal bones and molds is a unique resource for education and international research collaboration. Micro-computerized tomography (micro-CT) and synchrotron imaging are used to investigate the complex anatomy of the inner ear. Impaired microcirculation is etiologically linked to various inner ear disorders, and recent developments in inner ear surgery promote examination of the vascular system. Here, for the first time, we present three-dimensional (3D) data from investigations of the major vascular pathways and corresponding bone channels. METHODS We used the archival Uppsala collection of temporal bones and molds consisting of 324 inner ear casts and 113 macerated temporal bones. Micro-CT was used to investigate vascular bone channels, and 26 fresh human temporal bones underwent synchrotron radiation phase contrast imaging (SR-PCI). Data were processed by volume-rendering software to create 3D reconstructions allowing orthogonal sectioning, cropping, and soft tissue analyses. RESULTS Micro-CT with 3D rendering was superior in reproducing the anatomy of the vascular bone channels, while SR-PCI replicated soft tissues. Arterial bone channels were traced from scala vestibuli (SV) arterioles to the fundus, cochlea, and vestibular apparatus. Drainage routes along the aqueducts were examined. CONCLUSION Human inner ear vessels are difficult to study due to the adjoining hard bone. Micro-CT and SR-PCI with 3D reconstructions revealed large portions of the micro-vascular system in un-decalcified specimens. The results increase our understanding of the organization of the vascular system in humans and how altered microcirculation may relate to inner ear disorders. The findings may also have surgical implications.
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Affiliation(s)
- Xueshuang Mei
- Department of Surgical Sciences, Section of Otolaryngology, Uppsala University Hospital, Uppsala, Sweden
- Department of Otolaryngology, Peking University Shenzhen Hospital, P.R. China
| | - Francesca Atturo
- Department of Surgical Sciences, Section of Otolaryngology, Uppsala University Hospital, Uppsala, Sweden
| | - Karin Wadin
- Department of Diagnostic Radiology, Uppsala University Hospital, Uppsala, Sweden
| | - Sune Larsson
- Department of Surgical Sciences, Section of Orthopedics, Uppsala University Hospital, Sweden
| | - Sumit Agrawal
- Department of Otolaryngology-Head and Neck Surgery, Western University, Canada
| | - Hanif M. Ladak
- Department of Otolaryngology-Head and Neck Surgery, Western University, Canada
- Department of Medical Biophysics and Department of Electrical and Computer Engineering, Western University, Canada
| | - Hao Li
- Department of Surgical Sciences, Section of Otolaryngology, Uppsala University Hospital, Uppsala, Sweden
| | - Helge Rask-Andersen
- Department of Surgical Sciences, Section of Otolaryngology, Uppsala University Hospital, Uppsala, Sweden
- CONTACT Helge Rask-Andersen Department of Surgical Sciences, Section of Otolaryngology, Uppsala University Hospital, SE-751 85, Uppsala, Sweden
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The Human Cochlear Aqueduct and Accessory Canals: a Micro-CT Analysis Using a 3D Reconstruction Paradigm. Otol Neurotol 2018; 39:e429-e435. [DOI: 10.1097/mao.0000000000001831] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Agrawal S, Schart-Morén N, Liu W, Ladak HM, Rask-Andersen H, Li H. The secondary spiral lamina and its relevance in cochlear implant surgery. Ups J Med Sci 2018; 123. [PMID: 29537931 PMCID: PMC5901472 DOI: 10.1080/03009734.2018.1443983] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
OBJECTIVE We used synchrotron radiation phase contrast imaging (SR-PCI) to study the 3D microanatomy of the basilar membrane (BM) and its attachment to the spiral ligament (SL) (with a conceivable secondary spiral lamina [SSL] or secondary spiral plate) at the round window membrane (RWM) in the human cochlea. The conception of this complex anatomy may be essential for accomplishing structural preservation at cochlear implant surgery. MATERIAL AND METHODS Sixteen freshly fixed human temporal bones were used to reproduce the BM, SL, primary and secondary osseous spiral laminae (OSL), and RWM using volume-rendering software. Confocal microscopy immunohistochemistry (IHC) was performed to analyze the molecular constituents. RESULTS SR-PCI reproduced the soft tissues including the RWM, Reissner's membrane (RM), and the BM attachment to the lateral wall (LW) in three dimensions. A variable SR-PCI contrast enhancement was recognized in the caudal part of the SL facing the scala tympani (ST). It seemed to represent a SSL allied to the basilar crest (BC). The SSL extended along the postero-superior margin of the round window (RW) and immunohistochemically expressed type II collagen. CONCLUSIONS Unlike in several mammalian species, the human SSL is restricted to the most basal portion of the cochlea around the RW. It anchors the BM and may influence its hydro-mechanical properties. It could also help to shield the BM from the RW. The microanatomy should be considered at cochlear implant surgery.
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Affiliation(s)
- Sumit Agrawal
- Department of Otolaryngology-Head and Neck Surgery, Western University, London, ON, Canada
| | - Nadine Schart-Morén
- Department of Surgical Sciences, Section of Otolaryngology, Department of Otolaryngology, Uppsala University Hospital, Uppsala, Sweden
| | - Wei Liu
- Department of Surgical Sciences, Section of Otolaryngology, Department of Otolaryngology, Uppsala University Hospital, Uppsala, Sweden
| | - Hanif M. Ladak
- Department of Otolaryngology-Head and Neck Surgery, Western University, London, ON, Canada
- Department of Medical Biophysics and Department of Electrical and Computer Engineering, Western University, London, ON, Canada
| | - Helge Rask-Andersen
- Department of Surgical Sciences, Section of Otolaryngology, Department of Otolaryngology, Uppsala University Hospital, Uppsala, Sweden
- CONTACT Helge Rask-Andersen Department of Surgical Sciences, Head and Neck Surgery Section of Otolaryngology, Department of Otolaryngology, Uppsala University Hospital, SE-751 85, Uppsala, Sweden
| | - Hao Li
- Department of Surgical Sciences, Section of Otolaryngology, Department of Otolaryngology, Uppsala University Hospital, Uppsala, Sweden
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Yanov YK, Kuzovkov VE, Lilenko AS, Kostevich IV, Sugarova SB, Amonov AS. [Topographic anatomy of the hook region and its significance for the choice of the surgical technique for the cochlear implantation]. Vestn Otorinolaringol 2017. [PMID: 28631670 DOI: 10.17116/otorino20178234-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The mode of the introduction of the active electrode of a cochlear implant into the cochlea remains a key issue as far as cochlear implantation is concerned. Especially much attention has recently been given to the relationship between the anatomical features of the basal region of the cochlea (the so-called 'fish hook') and the possibility to approach it. We have undertaken the attempt to optimize the approach to the tympanic canal (scala tympanica) of the cochlea with a view to reducing to a minimum the risk of an injury to the cochlear structures in the course of cochlear implantation. A total of 35 cadaveric temporal bones were examined to measure the fine structures of the hook region and evaluate the risk of their damages associated with various approaches to the tympanic canal.
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Affiliation(s)
- Yu K Yanov
- Sankt-Petersburg Research Institute of Ear, Throat and Nose Diseases, Ministry of Health of the Russian Federation, Sankt-Petersburg, Russia, 190013
| | - V E Kuzovkov
- Sankt-Petersburg Research Institute of Ear, Throat and Nose Diseases, Ministry of Health of the Russian Federation, Sankt-Petersburg, Russia, 190013
| | - A S Lilenko
- Sankt-Petersburg Research Institute of Ear, Throat and Nose Diseases, Ministry of Health of the Russian Federation, Sankt-Petersburg, Russia, 190013
| | - I V Kostevich
- Sankt-Petersburg Research Institute of Ear, Throat and Nose Diseases, Ministry of Health of the Russian Federation, Sankt-Petersburg, Russia, 190013
| | - S B Sugarova
- Sankt-Petersburg Research Institute of Ear, Throat and Nose Diseases, Ministry of Health of the Russian Federation, Sankt-Petersburg, Russia, 190013
| | - A Sh Amonov
- Republican Research and Practical Medical Centre of Pediatrics, Tashkent, Uzbekistan, 100179
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Defining the Hook Region Anatomy of the Guinea Pig Cochlea for Modeling of Inner Ear Surgery. Otol Neurotol 2017; 38:e179-e187. [DOI: 10.1097/mao.0000000000001446] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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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.
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Emal T. Cochlear implantation in a subject with a narrow facial recess: Importance of preoperative radiological findings. Cochlear Implants Int 2016; 17:158-61. [PMID: 27160011 DOI: 10.1080/14670100.2016.1177261] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
OBJECTIVE This case report aims to emphasize the importance of preoperative computed tomography to evaluate the anatomy of the facial recess (FR) in order to prevent complications during cochlear implantation (CI) and to discuss alternative surgical approaches for the management of a narrow FR. Failure to notice this anomaly may result in facial nerve (FN) injury or inability to complete CI. CASE PRESENTATION A 50-year-old female with bilateral sensorineural hearing loss presented for CI. High-resolution CT (HRCT) demonstrated a narrow FR; specifically the space between the vertical segment of the FN and external auditory canal (EAC) was narrow. A section of the EAC was removed to obtain adequate exposure and was repaired with a cartilage graft following CI. CONCLUSION CI surgery may be difficult in patients with a narrow FR. Such surgical difficulty could be avoided if cochlear implant surgeons have adequate preoperative radiological imaging to evaluate the anatomy of the temporal bone. HRCT is the only modality that can detect this abnormality preoperatively. If the surgeon identifies this abnormality on preoperative HRCT, an alternative surgical technique could be used.
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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] [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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