Definition of Metrics to Evaluate Cochlear Array Insertion Forces Performed with Forceps, Insertion Tool, or Motorized Tool in Temporal Bone Specimens

Introduction. In order to achieve a minimal trauma to the inner ear structures during array insertion, it would be suitable to control insertion forces. The aim of this work was to compare the insertion forces of an array insertion into anatomical specimens with three different insertion techniques: with forceps, with a commercial tool, and with a motorized tool.Materials and Methods. Temporal bones have been mounted on a 6-axis force sensor to record insertion forces. Each temporal bone has been inserted, with a lateral wall electrode array, in random order, with each of the 3 techniques.Results. Forceps manual and commercial tool insertions generated multiple jerks during whole length insertion related to fits and starts. On the contrary, insertion force with the motorized tool only rose at the end of the insertion. Overall force momentum was 1.16 ± 0.505 N (mean ± SD,n=10), 1.337 ± 0.408 N (n=8), and 1.573 ± 0.764 N (n=8) for manual insertion with forceps and commercial and motorized tools, respectively.Conclusion. Considering force momentum, no difference between the three techniques was observed. Nevertheless, a more predictable force profile could be observed with the motorized tool with a smoother rise of insertion forces.

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Anatomic Considerations of the Medial Cuts in the Subtotal Temporal Bone Resection

Otolaryngology ◽

10.1177/019459988209000525 ◽

1982 ◽

Vol 90 (5) ◽

pp. 641-645 ◽

Cited By ~ 3

Author(s):

J. Gail Neely ◽

Michael Forrester

Keyword(s):

Temporal Bone ◽

Cranial Nerves ◽

Internal Auditory Canal ◽

Lateral Wall ◽

En Bloc Resection ◽

Bloc Resection ◽

Bone Resection ◽

En Bloc ◽

Temporal Bone Resection ◽

Temporal Bones

Eighteen temporal bones, 20 sets of polytomograms, and two sets of histologically sectioned temporal bones were studied and the literature was reviewed in order to describe the evolution and anatomic detail of the medial limits of the subtotal temporal bone resection used when malignant neoplasia has invaded the middle ear. An en bloc resection requires incisions medial to the pneumatized spaces involved. The anatomy of the lines of resection through the glenoid fossa, medial to the lateral wall of the carotid canal, through the cochlea, internal auditory canal, and jugular bulb, and just lateral to cranial nerves IX, X, and XI was described in detail. Regardless of the techniques employed, or the feasibility of the task, the concept of en bloc resection must conform to the anatomy of the region.

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Robot-Assisted Electrode Array Insertion Becomes Available in Pediatric Cochlear Implant Recipients: First Report and an Intra-Individual Study

Frontiers in Surgery ◽

10.3389/fsurg.2021.695728 ◽

2021 ◽

Vol 8 ◽

Author(s):

Huan Jia ◽

Jinxi Pan ◽

Wenxi Gu ◽

Haoyue Tan ◽

Ying Chen ◽

...

Keyword(s):

Cochlear Implantation ◽

Electrode Array ◽

Pure Tone Audiometry ◽

Lateral Wall ◽

Robot Assisted ◽

Insertion Depth ◽

Safety And Reliability ◽

Radiological Measurements ◽

Auditory Performance ◽

Temporal Bones

Background: As an advanced surgical technique to reduce trauma to the inner ear, robot-assisted electrode array (EA) insertion has been applied in adult cochlear implantation (CI) and was approved as a safe surgical procedure that could result in better outcomes. As the mastoid and temporal bones are generally smaller in children, which would increase the difficulty for robot-assisted manipulation, the clinical application of these systems for CI in children has not been reported. Given that the pediatric candidate is the main population, we aim to investigate the safety and reliability of robot-assisted techniques in pediatric cochlear implantation.Methods: Retrospective cohort study at a referral center in Shanghai including all patients of simultaneous bilateral CI with robotic assistance on one side (RobOtol® system, Collin ORL, Bagneux, France), and manual insertion on the other (same brand of EA and CI in both side), from December 2019 to June 2020. The surgical outcomes, radiological measurements (EA positioning, EA insertion depth, mastoidectomy size), and audiological outcomes (Behavior pure-tone audiometry) were evaluated.Results: Five infants (17.8 ± 13.5 months, ranging from 10 to 42 months) and an adult (39 years old) were enrolled in this study. Both perimodiolar and lateral wall EAs were included. The robot-assisted EA insertion was successfully performed in all cases, although the surgical zone in infants was about half the size in adults, and no difference was observed in mastoidectomy size between robot-assisted and manual insertion sides (p = 0.219). The insertion depths of EA with two techniques were similar (P = 0.583). The robot-assisted technique showed no scalar deviation, but scalar deviation occurred for one manually inserted pre-curved EA (16%). Early auditory performance was similar to both techniques.Conclusion: Robot-assisted technique for EA insertion is approved to be used safely and reliably in children, which is possible and potential for better scalar positioning and might improve long-term auditory outcome. Standard mastoidectomy size was enough for robot-assisted technique. This first study marks the arrival of the era of robotic CI for all ages.

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Evaluation of Intracochlear Trauma Caused by Insertion of Cochlear Implant Electrode Arrays through Different Quadrants of the Round Window

BioMed Research International ◽

10.1155/2015/236364 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 8

Author(s):

Graziela de Souza Queiroz Martins ◽

Rubens Vuono Brito Neto ◽

Robinson Koji Tsuji ◽

Eloisa Maria Mello Santiago Gebrim ◽

Ricardo Ferreira Bento

Keyword(s):

Cochlear Implant ◽

Round Window ◽

Electrode Array ◽

Hearing Preservation ◽

Round Window Membrane ◽

Residual Hearing ◽

Electrode Arrays ◽

Minimal Trauma ◽

Electrode Insertion ◽

Temporal Bones

Hypothesis. This study aimed to evaluate whether there is a difference in the degree of intracochlear trauma when the cochlear implant electrode arrays is inserted through different quadrants of the round window membrane.Background. The benefits of residual hearing preservation in cochlear implant recipients have promoted the development of atraumatic surgeries. Minimal trauma during electrode insertion is crucial for residual hearing preservation.Methods. In total, 25 fresh human temporal bones were subjected to mastoidectomy and posterior tympanotomy. The cochlear implant electrode array was inserted through the anterosuperior quadrant of the round window membrane in 50% of the bones and through the anteroinferior quadrant in the remaining 50%. The temporal bones were dehydrated, embedded in epoxy, serially polished, stained, viewed through a stereomicroscope, and photographed with the electrode arraysin situ. The resulting images were analyzed for signs of intracochlear trauma.Results. Histological examinations revealed varying degrees of damage to the intracochlear structures, although the incidence and severity of intracochlear trauma were not influenced by the quadrant of insertion.Conclusions. The incidence and severity of intracochlear trauma were similar in all samples, irrespective of electrode array insertion through the anterosuperior or anteroinferior quadrant of the round window membrane.

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Clinical investigation of the Nucleus Slim Modiolar Electrode

Audiology and Neurotology ◽

10.1159/000480345 ◽

2017 ◽

Vol 22 (3) ◽

pp. 169-179 ◽

Cited By ~ 29

Author(s):

Antje Aschendorff ◽

Robert Briggs ◽

Goetz Brademann ◽

Silke Helbig ◽

Joachim Hornung ◽

...

Keyword(s):

Computed Tomography ◽

Cochlear Implant ◽

Temporal Bone ◽

Clinical Investigation ◽

Round Window ◽

Electrode Array ◽

Lateral Wall ◽

Scala Tympani ◽

Flat Panel ◽

Insertion Depth

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

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The Pull-Back Technique for the 532 Slim Modiolar Electrode

BioMed Research International ◽

10.1155/2019/6917084 ◽

2019 ◽

Vol 2019 ◽

pp. 1-5 ◽

Cited By ~ 2

Author(s):

C. Riemann ◽

H. Sudhoff ◽

I. Todt

Keyword(s):

Temporal Bone ◽

Round Window ◽

Spiral Ganglion ◽

Electrode Array ◽

Electrode Arrays ◽

Current Spread ◽

Temporal Bones ◽

Hearing Outcomes ◽

White Marker

Introduction. The distance between the modiolus and the electrode array is one factor that has become the focus of many discussions and studies. Positioning the electrode array closer to the spiral ganglion with the goal of reducing the current spread has been shown to improve hearing outcomes. The perimodiolar electrode arrays can be complemented with a surgical manoeuvre called the pull-back technique. This study focuses its attention on the recently developed 532 slim modiolar electrode. Objective. To investigate the intracochlear movements and pull-back technique for the 532 slim modiolar electrode. Material and Methods. A decapping procedure of the cochlea was performed on 5 temporal bones. The electrode array was inserted, and the intracochlear movements were microscopically examined and digitally captured. Three situations were analysed: the initial insertion, the overinsertion, and the pull-back position. The position of the three white markers of the electrode array in relation to the round window (RW) was evaluated while performing these three actions. Results. The initial insertion achieved an acceptable perimodiolar position of the electrode array, but a gap was still observed between the mid-portion of the array and the modiolus (the first white marker was seen in the RW). When we inserted the electrode more deeply, the mid-portion of the array was pushed away from the modiolus (the second and third white markers were seen in the RW). After applying the pull-back technique, the gap observed during the initial insertion disappeared, resulting in an optimal perimodiolar position (the first white marker was once again visible in the RW). Conclusion. This temporal bone study demonstrated that when applying the pull-back technique for the 532 slim modiolar electrode, a closer proximity to the modiolus was achieved when the first white marker of the electrode array was visible in the round window.

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ROC Analysis of Three Perfusion Display Options for ECG-gated Perfusion SPECT in Severe CAD

Nuklearmedizin ◽

10.1055/s-0038-1632214 ◽

1999 ◽

Vol 38 (06) ◽

pp. 172-177

Author(s):

H. Bailer ◽

Marianne Gwechenberger ◽

Martha Pruckmayer ◽

A. Staudenherz ◽

G. Kronik ◽

...

Keyword(s):

Roc Analysis ◽

Lateral Wall ◽

Visual Assessment ◽

3D Mapping ◽

Operating Characteristics ◽

Gated Perfusion Spect ◽

Perfusion Spect ◽

Coronary Stenoses ◽

Definition Of ◽

Valve Plane

Summary Aim: The simultaneous computation and display of wall motion and perfusion patterns in a single 3D ventricular model would considerably ease the assessment of ECG-gated Tc-99m-sestamibi SPECT, yet the effect on the accuracy of allocating regional perfusion has so far not been validated. Methods: 3D perfusion mapping (3D Perfusion/Motion Map Software) was compared to the visual assessment of ungated tomographic slices and polar perfusion mapping (Cedars-Sinai PTQ) by correlation analysis and receiver operating characteristics (ROC) analysis at different cut-off levels for coronary stenoses in 50 patients (11 single-, 22 two-, 16 three-vessel disease). Ungated SPECT data were obtained by adding the intervals prior to reconstruction and displaying conventional tomographic slices. All display options were visually assessed in 8 ventricular segments according to a 4-point scoring system and compared to the graded results of coronary angiography. Results: All three display options showed a comparable diagnostic performance for the detection of severe stenoses. The diagnostic gain for the detection of stenoses above 59% was highest for ungated tomographic slices, followed by ungated polar mapping and 3D mapping. Regional assessment revealed a limited performance of 3D mapping in the proximal anterior and distal lateral wall. Polar mapping showed a balanced regional performance. Conclusion: 3D Perfusion mapping provides comparable information to conventional display options with the highest diagnostic strength in severe stenoses. Further improvement of the algorithm is needed in the definition of the valve plane.

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Intraoperative transimpedance and spread of excitation profile correlations with a lateral-wall cochlear implant electrode array

Hearing Research ◽

10.1016/j.heares.2021.108235 ◽

2021 ◽

Vol 405 ◽

pp. 108235

Author(s):

Samuel Söderqvist ◽

Satu Lamminmäki ◽

Antti Aarnisalo ◽

Timo Hirvonen ◽

Saku T. Sinkkonen ◽

...

Keyword(s):

Cochlear Implant ◽

Electrode Array ◽

Lateral Wall ◽

Excitation Profile ◽

Spread Of Excitation

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Otologic Histopathology of Fabry's Disease

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348948909800509 ◽

1989 ◽

Vol 98 (5) ◽

pp. 359-363 ◽

Cited By ~ 43

Author(s):

Patricia A. Schachern ◽

Michael M. Paparella ◽

Donald A. Shea ◽

Tae H. Yoon

Keyword(s):

Temporal Bone ◽

Ganglion Cells ◽

Spiral Ganglion ◽

Cell Loss ◽

The Body ◽

Spiral Ligament ◽

Fabry’S Disease ◽

Fabry's Disease ◽

Temporal Bones ◽

Spiral Ganglia

Fabry's disease is a rare progressive X-linked recessive disorder of glycosphingolipid metabolism. The accumulation of glycosphingolipids occurs in virtually all areas of the body, including the endothelial, perithelial, and smooth-muscle cells of blood vessels, the ganglion cells of the autonomic nervous system, and the glomeruli and tubules of the kidney. Although otologic symptoms have been described in these patients, to our knowledge there have been no temporal bone histopathologic reports. We describe the clinical histories, audiometric results, and temporal bone findings of two patients with this rare disorder. Both patients demonstrated a bilateral sloping sensorineural hearing loss audiometrically. Middle ear findings of seropurulent effusions and hyperplastic mucosa were seen in all four temporal bones. Strial and spiral ligament atrophy in all turns, and hair cell loss mainly in the basal turns, were also common findings. The number of spiral ganglion cells was reduced in all temporal bones; however, evidence of glycosphingolipid accumulation was not observed in the spiral ganglia.

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