scholarly journals Continuous Facial Nerve Stimulation During Cochlear Implantation – An Electrophysiological Technique to Control the Intracochlear Electrode Contact Position

2021 ◽  
Author(s):  
David Herrmann ◽  
Franz-Tassilo Müller-Graff ◽  
Stefan Kaulitz ◽  
Mario Cebulla ◽  
Anja Kurz ◽  
...  
Keyword(s):  
Facial Nerve ◽  
Cochlear Implantation ◽  
Electrode Position ◽  
Electric Pulses ◽  
Volume Computed Tomography ◽  
Basal Half ◽  
Apical Half ◽  
Electrode Insertion ◽  
Electrophysiological Technique ◽  
Contact Position

Abstract Purpose: This proof of concept describes the use of evoked electromyographic (EMG) activation of the facial nerve for intraoperative monitoring of the electrode insertion during cochlear implantation (CI).Methods: Intraoperative EMG measurements from the facial nerve were conducted in nine patients undergoing CI implantation. Electric pulses were emitted from contacts on the CI array during and immediately after electrode insertion. For control, the results of EMG measurements were compared to postoperative flat panel volume computed tomography scans with secondary reconstruction (fpVCTSECO).Results: During insertion, the EMG response evoked by the electrical stimulation from the CI was growing with the stimulating contact approaching the facial nerve and declined with increasing distance. After full insertion, contacts on the apical half of the CI array stimulated higher EMG responses compared with those on the basal half. Comparison with postoperative imaging demonstrated that electrode contacts stimulating high EMG responses had the shortest distances to the facial nerve. Conclusion: It could be demonstrated that electrically evoked EMG activation of the facial nerve can be used to monitor the progress during CI electrode insertion and to control the intracochlear electrode position after full insertion.

scholarly journals Imaging of Electrode Position after Cochlear Implantation with Flat Panel CT

2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
Diana Arweiler-Harbeck ◽  
Christoph Mönninghoff ◽  
Jens Greve ◽  
Thomas Hoffmann ◽  
Sophia Göricke ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Ct Scan ◽  
Cochlear Implantation ◽  
Electrode Array ◽  
Electrode Position ◽  
Flat Panel ◽  
Volume Computed Tomography ◽  
Metal Artefacts ◽  
Flat Panel Ct ◽  
Electrode Insertion

Background. Postoperative imaging after cochlear implantation is usually performed by conventional cochlear view (X-ray) or by multislice computed tomography (MSCT). MSCT after cochlear implantation often provides multiple metal artefacts; thus, a more detailed view of the implant considering the given anatomy is desirable. A quite new method is flat panel volume computed tomography. The aim of the study was to evaluate the method’s clinical use. Material and Methods. After cochlear implantation with different implant types, flat panel CT scan (Philips Allura) was performed in 31 adult patients. Anatomical details, positioning, and resolution of the different electrode types (MedEL, Advanced Bionics, and Cochlear) were evaluated interdisciplinary (ENT/Neuroradiology). Results. In all 31 patients cochlear implant electrode array and topographical position could be distinguished exactly. Spatial resolution and the high degree of accuracy were superior to reported results of MSCT. Differentiation of cochlear scalae by identification of the osseous spiral lamina was possible in some cases. Scanning artefacts were low. Conclusion. Flat panel CT scan allows exact imaging independent of implant type. This is mandatory for detailed information on cochlear electrode position. It enables us to perform optimal auditory nerve stimulation and allows feed back on surgical quality concerning the method of electrode insertion.

Cochlear implantation in the irradiated temporal bone

2006 ◽  
Vol 121 (1) ◽  
pp. 83-86 ◽  
Author(s):  
O F Adunka ◽  
C A Buchman
Keyword(s):  
Hearing Loss ◽  
Facial Nerve ◽  
Temporal Bone ◽  
Cochlear Implantation ◽  
Flap Reconstruction ◽  
Canal Wall ◽  
Free Flap Reconstruction ◽  
Canal Wall Down ◽  
Canal Wall Down Mastoidectomy ◽  
Electrode Insertion

Objective: To demonstrate the feasibility and complexities of cochlear implantation in the setting of bilateral temporal bone osteoradionecrosis.Study design: Case report.Setting: Tertiary care referral centre.Case description: A 66-year-old woman with bilateral temporal bone osteoradionecrosis and profound hearing loss, following treatment for tonsillar cancer, underwent cochlear implantation. Prior canal wall down mastoidectomy and subsequent temporal bone resection with free flap reconstruction had been performed on the implanted ear. The contralateral ear received a canal wall down mastoidectomy. A completely dehiscent mastoid segment of the facial nerve and extensive fibrosis were evident in the implanted ear. Only minimal fibrous reaction was found within the cochlea, allowing for full electrode insertion. At three months, speech recognition testing documented a consonant-nucleus-consonant (CNC) word score of 54 per cent.Conclusions: This report demonstrates the feasibility of cochlear implantation after temporal bone surgery and free flap reconstruction in the setting of diffuse osteoradionecrosis. The patient's excellent open-set speech understanding using the cochlear implant implies that radiation did not severely damage the central auditory pathways. Thus, some patients with radiation-induced hearing loss may be appropriate cochlear implant candidates. Special attention should be paid to surgical planning, as complications related to wound healing, electrode insertion and facial nerve injury may be more likely.

Surgical considerations during cochlear implantation: the utility of temporal bone computed tomography

2021 ◽  
pp. 1-8
Author(s):  
Beomcho Jun ◽  
Sunwha Song
Keyword(s):  
Computed Tomography ◽  
Temporal Bone ◽  
Cochlear Implantation ◽  
Round Window ◽  
Three Dimensional ◽  
Electrode Placement ◽  
Posterior Tympanotomy ◽  
Electrode Insertion ◽  
Window Approach ◽  
Bone Structures

Abstract Objective This paper describes the construction of portals for electrode placement during cochlear implantation and emphasises the utility of pre-operative temporal bone three-dimensional computed tomography. Methods Temporal bone three-dimensional computed tomography was used to plan portal creation for electrode insertion. Results Pre-operative temporal bone three-dimensional computed tomography can be used to determine the orientation of temporal bone structures, which is important for mastoidectomy, posterior tympanotomy and cochleostomy, and when using the round window approach. Conclusion It is essential to create appropriate portals (from the mastoid cortex to the cochlea) in a step-by-step manner, to ensure the safe insertion of electrodes into the scala tympani. Pre-operative three-dimensional temporal bone computed tomography is invaluable in this respect.

New injurious Curculionidae (Col.)

1931 ◽  
Vol 22 (3) ◽  
pp. 417-421 ◽  
Author(s):  
Guy A. K. Marshall
Keyword(s):  
Median Carina ◽  
Basal Half ◽  
Transverse Stria ◽  
Apical Half ◽  
Basal Width

Aedophronus echinatus, sp. n. (Pl. xxi, fig. 2).Derm black, with dense brown scaling, usually with an indefinite mottling of darker and paler scales ; the inflexed margins of the elytra fuscous.Head not very convex, with the median stria extending to the vertex and the anterior transverse stria slightly curved ; the infra-ocular margin much narrower than the base of the scape and not projecting ; the setae short, stout and curved backwards ; the eyes comparatively large, highest much behind the middle, and with the hind margin devoid of scaling. Rostrum longer than the head (5·5 : 4), much shorter than its basal width (5·5 : 7·5), narrowed in front, straight at the sides, with a shallow impression on the apical half and with no median carina ; the marginal carina of the epistome obtuse but distinct. Prothorax transverse (3·5 : 6), strongly rounded at the sides, widest at the middle, subtruncate at the apex, which is only slightly narrower than the base ; the dorsum with an abbreviated median stria on the basal half and bearing on the disk short curved setae like those on the head, the lateral ones much longer, stout, straight and pointed (when unbroken), the longest being about as long as the scape.

Facial Nerve Stimulation with Cochlear Implantation

1991 ◽  
Vol 104 (6) ◽  
pp. 826-830 ◽  
Author(s):  
John K. Niparko ◽  
Dana L. Oviatt ◽  
Newton J. Coker ◽  
Lois Sutton ◽  
Susan B. Waltzman ◽  
...  
Keyword(s):  
Facial Nerve ◽  
Nerve Stimulation ◽  
Cochlear Implantation ◽  
Facial Nerve Stimulation

An HRCT based scoring system to predict ease of electrode insertion in Cochlear Implantation

2021 ◽  
pp. 1-20
Author(s):  
Arindam Das ◽  
Mridul Janweja ◽  
Aryabrata Dubey ◽  
Sandipta Mitra ◽  
Arunabha Sengupta
Keyword(s):  
Cochlear Implantation ◽  
Scoring System ◽  
Electrode Insertion

scholarly journals Herniation of the Mastoid Segment of the Facial Nerve During Cochlear Implantation Surgery

2021 ◽  
pp. 014556132110516
Author(s):  
Mohammad Almohammad ◽  
Tala Tasabehji ◽  
Abdulrahman Awad ◽  
Ibrahem Hanafi
Keyword(s):  
Facial Nerve ◽  
Hearing Aids ◽  
Cochlear Implantation ◽  
Round Window ◽  
Posterior Wall ◽  
Case Presentation ◽  
Posterior Tympanotomy ◽  
Bilateral Sensorineural Hearing Loss ◽  
The Right ◽  
Electrical Stimuli

Background: We aim to report a rare case of a herniated mastoid segment of the facial nerve that was accidently discovered during cochlear implantation surgery and how altering the surgery plan could achieve the implantation while preserving the nerve. Case presentation: A four-year-old girl presented with profound bilateral sensorineural hearing loss that did not completely resolve after 2 years of using hearing aids was scheduled for cochlear implantation surgery in the right ear. During surgery, a herniated mastoid segment of the facial nerve took an anterior course and obstructed the access to the round window. Conclusion: When a traditional posterior tympanotomy approach in cochlear implantation surgery is limited in cases of a herniated facial nerve, a tunnel created near the inferior part of the posterior wall of the auditory canal provided safe insertion of the electrode. It also permitted placement of a piece of fascia between the electrode and the facial nerve, therefore, protecting the facial nerve from electrical stimuli.

Outcome of Cochlear Implantation in Postmeningitis Profound Sensorineural Hearing Loss at Rajavithi Hospital

2021 ◽  
Vol 104 (2) ◽  
pp. 260-263
Keyword(s):  
Hearing Loss ◽  
Sensorineural Hearing Loss ◽  
Cochlear Implantation ◽  
Sensorineural Hearing ◽  
Preoperative Imaging ◽  
Profound Hearing Loss ◽  
Language Status ◽  
Auditory Performance ◽  
Electrode Insertion ◽  
One Year

Background: Bacterial meningitis is one of the major factors in the etiology of acquired sensorineural hearing loss in children and adults. Cochlear implantation in these patients is challenging because of inner ear ossification and fibrosis, and this procedure sometimes achieves poorer outcomes in this scenario than with other causes of sensorineural hearing loss. There has been little research into the factors affecting the outcomes of this procedure. Objective: To evaluate the outcomes of cochlear implantation in patients with postmeningitis profound sensorineural hearing loss and to evaluate the factors that affect the results. Materials and Methods: A retrospective review was conducted of thirty patients who were diagnosed with post meningitis profound hearing loss and underwent cochlear implantation at Rajavithi Hospital between 2001 and 2016. Preoperative language status, duration of deafness, preoperative imaging, and degree of electrode insertion were recorded. Categories of auditory performance-II test (CAP-II) was evaluated in all cases, one year postoperative. Results: Thirty postmeningitis deafness patients underwent cochlear implantation. The median age at diagnosis of meningitis and age at implantation were 41 years (range 1 to 75) and 49.50 years (range 3 to 75), respectively. The median duration of deafness was 12 months (range 4 to 300), and the overall mean CAP-II at one year after surgery was 5.47±2.21. The postlinguistic group had a significantly higher CAP-II score than the prelinguistic one (p=0.006). Electrodes were successfully totally inserted in 19 patients (63.3%) and partially inserted in 11 (36.7%). The average CAP-II score in the group with fully-inserted electrodes was significantly higher than in the group with partially-inserted electrodes (p=0.045). There was no correlation between CAP-II score and age at meningitis diagnosis (p=0.069), age at time of surgery (p=0.105), duration of deafness (p=0.506), or preoperative CT (p=0.228) or MRI abnormality (p=0.078). Conclusion: Cochlear implantation in patients with postmeningitis profound hearing loss had high success rates and favorable outcomes. Preoperative language status and degree of electrode insertion were factors that affected auditory performance results. Keywords: Cochlear implantation, Postmeningitis hearing loss, Sensorineural hearing loss, Meningitis, Rajavithi Hospital

scholarly journals Temporal branch of facial nerve: a normative study of nerve conduction

2010 ◽  
Vol 68 (4) ◽  
pp. 619-622 ◽  
Author(s):  
Paula Fabiana Sobral da Silva ◽  
Maria Carolina Martins de Lima ◽  
José Natal Figueiroa ◽  
Otávio Gomes Lins
Keyword(s):  
Facial Nerve ◽  
Conduction Velocity ◽  
Normative Values ◽  
Normative Study ◽  
Traumatic Injuries ◽  
Additional Information ◽  
The Face ◽  
Electrophysiological Technique ◽  
Clinical Conditions ◽  
The Temple

The temporal branch of the facial nerve is particularly vulnerable to traumatic injuries during surgical procedures. It may also be affected in clinical conditions. Electrodiagnostic studies may add additional information about the type and severity of injuries, thus allowing prognostic inferences. The objective of the present study was to develop and standardize an electrophysiological technique to specifically evaluate the temporal branch of the facial nerve. METHOD: Healthy volunteers (n=115) underwent stimulation of two points along the nerve trajectory, on both sides of the face. The stimulated points were distal (on the temple, over the temporal branch) and proximal (in retro-auricular region). Activities were recorded on the ipsilateral frontalis muscle. The following variables were studied: amplitude (A), distal motor latency (DML) and conduction velocity (NCV). RESULTS: Differences between the sides were not significant. The proposed reference values were: A >0.4 mV, DML <3.9 ms and NCV >40 m/s. Variation between hemifaces should account for less than 60% for amplitudes and latency, and should be inferior to 20% for conduction velocity. CONCLUSION: These measurements are an adequate way for proposing normative values for the electrophysiological evaluation of the temporal branch.

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