scholarly journals Az elektródasor visszatekeredésének kimutatása transzimpedanciamátrix (TIM)-vizsgálattal cochlearis implantátumban

2021 ◽  
Vol 162 (25) ◽  
pp. 988-996
Author(s):  
Roland Nagy ◽  
Ádám Perényi ◽  
Balázs Dimák ◽  
Miklós Csanády ◽  
József Kiss ◽  
...  
Keyword(s):  
Cochlear Implantation ◽  
Imaging Techniques ◽  
Electrode Array ◽  
Hearing Preservation ◽  
Constant Current ◽  
Measuring Device ◽  
Electrophysiological Measurements ◽  
Electrophysiological Studies ◽  
Intracochlear Electrode Array ◽  
The Right

Összefoglaló. Bevezetés: Az elmúlt években a cochlearis implantátum a súlyos halláskárosodás vagy a teljes siketség rutinszerű és hatékony kezelési eszközévé vált. Korunk egyik leggyakrabban használt és leghatékonyabb újítása a cochlearis implantációban a perimodiolaris vékony elektródasorok alkalmazása. A cochlea középtengelyét, a modiolust szorosan ölelő atraumatikus elektródasor igen meggyőző eredménnyel bizonyítja népszerűségét, mind az elektrofiziológiai mérések során, mind az akusztikus hallás megőrzése terén nyújtott teljesítményével. Ugyanakkor igen kevés publikáció írja le az elektródasor nem megfelelő helyzetének előfordulási gyakoriságát, pontosabban a visszatekeredését a csúcsi szakaszon. Célkitűzés: Tanulmányunk célja olyan szoftveres technika, a transzimpedancia-mátrix (TIM) beillesztése a rutin intraoperatív elektrofiziológiai mérési metodikák közé, amely képes objektív diagnosztikai lehetőséget biztosítani ahhoz, hogy korán felismerhessük a cochlearis implantátum elektródasorán keletkezett hurkot. Módszer: Hároméves kisgyermek kétoldali cochlearis implantációját követően, posztoperatív röntgenfelvételen a bal oldalon az elektródasor megfelelő pozíciója figyelhető meg, míg a jobb oldalon az intracochlearis elektródasor végének visszatekeredése igazolódott. Képalkotó vizsgálatot követően elektrofiziológiai metódusként TIM-vizsgálatot végeztünk. Az eljárás során a mérőeszköz a kijelölt stimuláló elektródákon 1 V nagyságrendű feszültséget közöl állandó áramerősség mellett a cochlea közel eső struktúrái felé. Mérőelektródák segítségével regisztráljuk a szöveteken mérhető feszültséget, majd transzimpedancia-mátrixszá alakítjuk a mért értékeket. Eredmények: Az elektródasor visszatekeredése, amelyet korábban radiológiai vizsgálattal igazoltunk, az objektív elektrofiziológiai mérések segítségével is jól azonosítható, és a vizsgálatok szoros párhuzamot mutatnak. Következtetés: Az elektródák helyzetének megjelenítésére szolgáló standard radiológiai képalkotási technikák kiegészíthetők, illetve kiválthatók egyszerűen elvégezhető, hatékony, objektív elektrofiziológiai vizsgálatokkal. Intraoperatíven, még a sebzárás előtt kimutatható, ha az elektródasor nem megfelelő helyzetbe került, így csökkenthetjük a radiológiai vizsgálatokkal járó sugárterhelés és annak finanszírozási problémáját. Orv Hetil. 2021; 162(25): 988–996. Summary. Introduction: In recent years, the cochlear implant has become a routine and effective treatment tool for severe hearing loss and total deafness. One of the commonly used and effective innovations of our time in cochlear implantation is the perimodiolar thin electrode array. The atraumatic electrode array, which closely embraces the central axis of the cochlea (modiolus), has served its popularity with very convincing results, with its performance in both electrophysiological measurements and acoustic hearing preservation. However, very few publications describe the frequency of improper positioning of the electrode array, which is known as ‘tip fold-over’. Objective: The aim of our study is to incorporate a software technique, the transimpedance matrix (TIM), into routine intraoperative electrophysiological measurement methodologies to provide a potential objective diagnostic opportunity for early detection of tip fold-over of the electrode array. Method: Following bilateral cochlear implantation of a three-year-old child, postoperative radiography showed the correct position of the electrode array on the left side, while tip fold-over of the intracochlear electrode array was detected on the right side. Following imaging, a TIM study was performed as an electrophysiological method. During the procedure, the measuring device transmits a voltage of the order of 1 V to the nearby structures of the cochlea at a constant current at the designated stimulus electrodes. Measuring electrodes were used to register the voltage measured on the tissues, and then converted into a TIM. Results: Electrode tip fold-over was previously diagnosed by radiological examination, while it can also be diagnosed by objective electrophysiological measurements now, and these two tests correlate well. Conclusion: Standard radiological imaging techniques for electrode positioning can be supplemented or replaced by easy-to-perform, effective objective electrophysiological studies. Tip fold-over can be detected intraoperatively, even before wound closure, if the electrode array is in the wrong position, thus reducing the radiation exposure associated with radiological examinations as well as reducing relevant costs. Orv Hetil. 2021; 162(25): 988–996.

The Impact of Electrode Array Length on Hearing Preservation in Cochlear Implantation

2016 ◽  
Vol 37 (8) ◽  
pp. 1006-1015 ◽  
Author(s):  
Marie-Charlot Suhling ◽  
Omid Majdani ◽  
Rolf Salcher ◽  
Melanie Leifholz ◽  
Andreas Büchner ◽  
...  
Keyword(s):  
Cochlear Implantation ◽  
Electrode Array ◽  
Hearing Preservation ◽  
The Impact

Evolution of electrode array diameter for hearing preservation in cochlear implantation

2012 ◽  
Vol 133 (2) ◽  
pp. 116-122 ◽  
Author(s):  
Yann Nguyen ◽  
Isabelle Mosnier ◽  
Stéphanie Borel ◽  
Emmanuelle Ambert-Dahan ◽  
Didier Bouccara ◽  
...  
Keyword(s):  
Cochlear Implantation ◽  
Electrode Array ◽  
Hearing Preservation

Another reason for intra-operative imaging during cochlear implantation

2008 ◽  
Vol 122 (4) ◽  
Author(s):  
M Viccaro ◽  
E De Seta ◽  
E Covelli ◽  
V Marvaso ◽  
R Filipo
Keyword(s):  
Cochlear Implant ◽  
Semicircular Canal ◽  
Cochlear Implantation ◽  
Electrode Array ◽  
Neural Response ◽  
Radiological Assessment ◽  
Implant Surgery ◽  
Stimulation Intensity ◽  
Cochlear Implant Surgery ◽  
The Right

AbstractObjective:We report a case of a rare cochlear implant complication: the introduction of the electrode array into the superior semicircular canal, with intra-operative measurements of neural response reactions suggesting reasonable functioning of the implant.Case report:A two-year old patient affected by congenital, profound, sensorineural deafness underwent bilateral cochlear implantation at the ENT clinic of the ‘La Sapienza’ University of Rome. Two Clarion 90k devices were implanted, and electrophysiological and radiological checks were performed. After the introduction of the array in the right side, neural response imaging was performed, and a neural potential was found only on two apical electrodes, at a stimulation intensity of 431 clinical units. The situation differed on the left side, where neural response imaging was present at a stimulation intensity of 300 clinical units on the two electrodes tested (one apical electrode (number three), and one middle electrode (number nine)). Intra-operative radiological assessment with a transorbital plain films was performed as usual in order to assess the position of the electrodes inside the cochlea. This radiography showed the electrode array to be in the superior semicircular canal in the right ear.Conclusion:Intra-operative monitoring tests during cochlear implant surgery play different roles; measurement of impedances and neural response imaging can evaluate the integrity of implant electrodes and the status of the electrode–cochlea interface, but it must not be the sole way in which correct positioning of the array is confirmed. In our opinion, intra-operative radiological assessment is mandatory during cochlear implant surgery.

scholarly journals A maradványhallás megőrzésének lehetőségei cochlearis implantáció során Nucleus CI532 Slim Modiolar elektródasorral

2018 ◽  
Vol 159 (41) ◽  
pp. 1680-1688 ◽  
Author(s):  
Roland Nagy ◽  
János András Jarabin ◽  
Balázs Dimák ◽  
Ádám Perényi ◽  
Ferenc Tóth ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Minimally Invasive ◽  
Cochlear Implantation ◽  
Basilar Membrane ◽  
Round Window ◽  
Spiral Ganglion ◽  
Hearing Threshold ◽  
Electrode Array ◽  
Hearing Preservation ◽  
Residual Hearing

Abstract: During the rehabilitation of hearing-impaired patients, the preservation of residual acoustic hearing following cochlear implantation by minimizing the implantation trauma allows for improved hearing performance. To achieve this, minimally invasive, soft surgery methods and thinner, atraumatic electrodes were required. In our present study, we reported a case where Cochlear® Nucleus CI532 Slim Modiolar electrode was implanted in a patient with residual hearing. Our aim was to study the possible preservation of postoperative acoustic residual hearing by audiological monitoring. Since childhood, due to her congenital hearing loss, she has been wearing a conventional, airborne hearing correction device on both ears. Six months before cochlear implantation, we measured the progression on both sides of the hearing loss, so we decided to perform cochlear implantation. The patient had residual hearing on both ears prior to surgery thus the Cochlear® Nucleus CI532 Slim Modiolar Implant was used. The minimally invasive surgery was performed on the patient’s right ear through the round window approach. Compared to the preoperative hearing threshold (average 85 dBHL) in the 4th postoperative week, an initial hearing threshold progression of 20–25 dBHL was observed between 0.25 and 1.0 kHz, while of 5–10 dBHL between 2.0–4.0 kHz. Hearing threshold measured in the 6th month showed a slight progression in the range above 1 kHz, but improved by the 12th month, to the results achieved at the 4th week. The effects of cochlear implantation on residual hearing have been studied in numerous studies, in which several key surgical and technical factors have been identified. Nucleus CI532 is a Slim Modiolar electrode profile that is close to the modiolus, so it is expected to have a lower endocochlear hydrodynamic load since it lies in the covering of the osseus spiral lamina, thus less influencing the dynamics of the basilar membrane. However, the perimodiolar location of the electrode array allows the adjacent nerve elements of the spiral ganglion to be stimulated with a lower electrical intensity and a reduced surface that may be neuroprotective. Preservation of acoustic residual hearing following cochlear implantation improves the patient’s speech perception and the sound localization skills, particularly in difficult circumstances. Long-term residual hearing preservation may also be of great importance in the subsequent feasibility for regenerative procedures and drug treatments. Orv Hetil. 2018; 159(41): 1680–1688.

Initial hearing preservation outcomes of cochlear implantation with a slim perimodiolar electrode array

2021 ◽  
pp. 1-9
Author(s):  
Erika Woodson ◽  
Rebecca Chota Nelson ◽  
Molly Smeal ◽  
Thomas Haberkamp ◽  
Sarah Sydlowski
Keyword(s):  
Cochlear Implantation ◽  
Electrode Array ◽  
Hearing Preservation

Preservation of residual hearing following cochlear implantation: comparison between three surgical techniques

2007 ◽  
Vol 122 (3) ◽  
pp. 246-252 ◽  
Author(s):  
S Berrettini ◽  
F Forli ◽  
S Passetti
Keyword(s):  
Cochlear Implant ◽  
Cochlear Implantation ◽  
Surgical Techniques ◽  
Electrode Array ◽  
Lateral Wall ◽  
Hearing Preservation ◽  
Acoustic Stimulation ◽  
Residual Hearing ◽  
Electrode Arrays ◽  
Electrode Insertion

AbstractThe preservation of residual hearing is becoming a high priority in cochlear implant surgery. It allows better speech understanding and ensures long-lasting and stable performance; it also allows the possibility, in selected cases, of combining electro-acoustic stimulation in the same ear.We present the results of a retrospective study of the conservation of residual hearing in three different groups of patients who had undergone cochlear implantation using three different cochlear implant electrode arrays, combined with three different surgical techniques for the cochleostomy. The study aimed to evaluate which approach allowed greater preservation of residual hearing.The best residual hearing preservation results (i.e. preservation in 81.8 per cent of patients) were achieved with the Contour Advance electrode array, using the Advance Off-Stylet technique and performing a modified anterior inferior cochleostomy; this combination enabled reduced trauma to the lateral wall of the cochlea during electrode insertion.

US-guided percutaneous microwave ablation (MWA) of submandibular gland: A new minimal invasive and effective treatment for refractory sialorrhea and treatment response evaluation with contrast-enhanced imaging techniques

2021 ◽  
pp. 1-12
Author(s):  
Hui-Li Zhang ◽  
Jing-E Zhu ◽  
Jia-Xin Li ◽  
Xiao-Long Li ◽  
Li-Ping Sun ◽  
...  
Keyword(s):  
Effective Treatment ◽  
Submandibular Gland ◽  
Microwave Ablation ◽  
Imaging Techniques ◽  
Symptom Relief ◽  
Minimal Invasive ◽  
Whole Saliva ◽  
Patient Reported ◽  
The Right ◽  
Percutaneous Microwave Ablation

A 33 years’ old male complained of excessive salivation with frequent swallowing and spitting, which resulted in communication disturbance, reduced quality of life, and social embarrassment for 19 years. He had been diagnosed as sialorrhea and submandibular gland hyperfunction by stomatologist, then had unilateral submandibular gland resection 13 years ago, but the symptom relief was not satisfactory. After that, he had been treated with glycopyrrolate for less than a year, which was withdrawn because of the short duration of symptomatic control after each tablet take-in and intolerable side effects. With the wish to receive a new treatment with long term effectiveness, low re-operation risk and normal preserved saliva secretion function, the patient was subject to MWA for the right submandibular gland. After systematic clinical evaluation, US-guided percutaneous MWA was successfully performed with an uneventful post-operative course. The volume of the right submandibular gland and ablated area were measured precisely by an ablation planning software system with automatic volume measurement function based on three-dimensional reconstruction of the pre-operative and post-operative enhanced magnetic resonance imaging (MRI) raw data. Finally, the ablated volume was calculated as 62.2% of the whole right submandibular gland. The patient was discharged 1 day after the operation, with symptoms relieved significantly, the mean value of whole saliva flow rate (SFR) decreased from 11 ml to 7.5 ml per 15 minutes. During the follow up by phone three months after operation, the patient reported that the treatment effect was satisfactory, whereas the SFR value became stable as 7 ml per 15 minutes, drooling frequency and drooling severity (DFDS) score decreased from 6 to 5, drooling impact scale (DIS) score decreased from 43 to 26. US-guided percutaneous MWA of submandibular gland seems to be an alternative, minimal invasive, and effective treatment for refractory sialorrhea. We described a patient with refractory sialorrhea treated successfully with ultrasound (US) guided percutaneous microwave ablation (MWA).

CNT bundle-based thin intracochlear electrode array

2019 ◽  
Vol 21 (1) ◽  
Author(s):  
Gwang Jin Choi ◽  
Tae Mok Gwon ◽  
Doo Hee Kim ◽  
Junbeom Park ◽  
Seung Min Kim ◽  
...  
Keyword(s):  
Electrode Array ◽  
Intracochlear Electrode Array

scholarly journals A framework of current based defibrillation improves defibrillation efficacy of biphasic truncated exponential waveform in rabbits

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Weiming Li ◽  
Jingru Li ◽  
Liang Wei ◽  
Jianjie Wang ◽  
Li Peng ◽  
...  
Keyword(s):  
Pulse Duration ◽  
Rabbit Model ◽  
Constant Current ◽  
Shock Duration ◽  
Peak Voltage ◽  
Peak Current ◽  
High Impedance ◽  
Shock Impedance ◽  
Energy Peak ◽  
The Right

AbstractDefibrillation is accomplished by the passage of sufficient current through the heart to terminate ventricular fibrillation (VF). Although current-based defibrillation has been shown to be superior to energy-based defibrillation with monophasic waveforms, defibrillators with biphasic waveforms still use energy as a therapeutic dosage. In the present study, we propose a novel framework of current-based, biphasic defibrillation grounded in transthoracic impedance (TTI) measurements: adjusting the charging voltage to deliver the desired current based on the energy setting and measured pre-shock TTI; and adjusting the pulse duration to deliver the desired energy based on the output current and intra-shock TTI. The defibrillation efficacy of current-based defibrillation was compared with that of energy-based defibrillation in a simulated high impedance rabbit model of VF. Cardiac arrest was induced by pacing the right ventricle for 60 s in 24 New Zealand rabbits (10 males). A defibrillatory shock was applied with one of the two defibrillators after 90 s of VF. The defibrillation thresholds (DFTs) at different pathway impedances were determined utilizing a 5-step up-and-down protocol. The procedure was repeated after an interval of 5 min. A total of 30 fibrillation events and defibrillation attempts were investigated for each animal. The pulse duration was significantly shorter, and the waveform tilt was much lower for the current-based defibrillator. Compared with energy-based defibrillation, the energy, peak voltage, and peak current DFT were markedly lower when the pathway impedance was > 120 Ω, but there were no differences in DFT values when the pathway impedance was between 80 and 120 Ω for current-based defibrillation. Additionally, peak voltage and the peak current DFT were significantly lower for current-based defibrillation when the pathway impedance was < 80 Ω. In sum, a framework of adjusting the charging voltage and shock duration to deliver constant energy for low impedance and constant current for high impedance via pre-shock and intra-shock impedance measurements, greatly improved the defibrillation efficacy of high impedance by lowering the energy DFT.

Cochlear implantation in a patient with severe cochlear hypoplasia

2012 ◽  
Vol 126 (11) ◽  
pp. 1172-1175 ◽  
Author(s):  
Y M Feng ◽  
Y Q Wu ◽  
J Wang ◽  
S K Yin
Keyword(s):  
Case Report ◽  
Cochlear Implantation ◽  
Internal Auditory Canal ◽  
Electrode Array

AbstractObjective:We report the case of a successful cochlear implantation in a patient with severe cochlear hypoplasia.Case report:The outcome of cochlear implantation is generally less favourable for patients with cochlear hypoplasia than for those with a normal cochlear structure. In the reported patient, part of the electrode array was inserted into the internal auditory canal. Nevertheless, the benefits following cochlear implantation seemed to outweigh the risks for this patient.Conclusion:Cochlear hypoplasia is not necessarily a contraindication for cochlear implantation.

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