Dataset Information

An Improved Technique of Subtotal Cochleoectomy for Removal of Intracochlear Schwannoma and Single-stage Cochlear Implantation.

ABSTRACT: : Cochlear implantation in patients with intracochlear schwannomas has been reported anecdotally in case reports or small case series . The applied techniques have varied considerably ranging from extended cochleostomy , "push-through" and "pull-through" techniques , partial and subtotal cochleoectomy to cochlear implant insertion through the tumor (5). We here illustrate (see Video, Supplemental Digital Content 1, http://links.lww.com/MAO/A999) our improved surgical technique of subtotal cochleoectomy for tumor removal, cochlear implantation, and cochlear defect reconstruction with a "cartilage-in-perichondrium-bed" technique. The perimodiolar electrode array was closely placed around the preserved modiolus of the basal and second turn. It was stabilized and the electrodes were further approximated to the spiral ganglion cells in Rosenthal's canal with cartilage chips peripheral to the array. Despite substantial trauma to the cochlear capsule, surprisingly good results with respect to hearing rehabilitation were observed (word recognition score for monosyllables: 75% at 65 dB SPL, 18 mo after surgery). This good outcome is in accordance with recent case series on cochlear implantation after intracochlear tumor removal .

SUBMITTER: Plontke SK

PROVIDER: S-EPMC7373454 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

An Improved Technique of Subtotal Cochleoectomy for Removal of Intracochlear Schwannoma and Single-stage Cochlear Implantation.

Plontke Stefan K SK

Otology & neurotology : official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology 20200801 7

: Cochlear implantation in patients with intracochlear schwannomas has been reported anecdotally in case reports or small case series . The applied techniques have varied considerably ranging from extended cochleostomy , "push-through" and "pull-through" techniques , partial and subtotal cochleoectomy to cochlear implant insertion through the tumor (5). We here illustrate (see Video, Supplemental Digital Content 1, http://links.lww.com/MAO/A999) our improved surgical technique of subtotal cochle ...[more]

PMID: 32658406

Similar Datasets

Project description:Subtotal petrosectomy (STP) has been more frequently performed to prepare ears with unfavorable conditions for cochlear implantation. To provide an overview of indications for and complications of STP and cochlear implantation and to compare outcomes between single vs multistage procedures and between pediatric vs adult populations. A search of PubMed, Scopus, Ovid, and the Cochrane Library was performed from the databases' inception to January 23, 2020, for studies evaluating STP for cochlear implantation. Studies with a minimum follow-up of 3 months and no missing data regarding postoperative outcomes were included. Of the initial 570 studies identified, 27 (4.7%) met selection criteria. Two reviewers independently assessed study eligibility according to Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines; discrepancies were resolved by a third reviewer. Extracted data included patient demographics, indications for STP, rates of complications, and cholesteatoma recidivism when applicable. Data were pooled using a random- or a fixed-effects model when appropriate. The primary study outcome was rate of global complications stratified by patient- and surgery-level characteristics. Twenty-seven unique studies with 377 unique patients (54.2% male; mean age, 50.6 [range, 1-99] years) undergoing 397 STP procedures and cochlear implantation were included. Of these procedures, 299 of 394 cases with the information reported (75.9%) were single procedures and 95 (24.1%) were multistage procedures. Of the total 397 STP procedures, most common indications included chronic otitis media (220 cases [55.4%]), previous open mastoid cavity (141 [35.5%]), cholesteatoma (74 [18.6%]), and cochlear ossification (29 [7.3%]). The overall complication rate was 12.4% (95% CI, 9.4%-15.9%); overall cholesteatoma recidivism rate was 9.3% (95% CI, 4.3%-17.1%). Complication rates did not significantly differ based on stage or age of patients. Cases with cholesteatoma more often underwent multistage vs single-stage procedures (23 of 54 [42.6%] vs 35 of 174 [20.1%]). Across all age groups, STP has been shown to be an effective surgical operation in preparing an ear with unfavorable conditions for cochlear implantation. The potential indications for which cochlear implantation can be performed have expanded with the use of STP. Presence of cholesteatoma might indicate that a multistage procedure should be performed. Lastly, with complication rates comparable to those in adult patients, STP can be considered in children requiring cochlear implantation to minimize ear-related issues and allow benefit from cochlear implantation.

Project description:IntroductionCochlear implants (CIs) restore hearing to deafened patients. The foreign body response (FBR) following cochlear implantation (post-CI) comprises an infiltration of macrophages, other immune and non-immune cells, and fibrosis into the scala tympani; a space that is normally devoid of cells. This FBR is associated with negative effects on CI outcomes including increased electrode impedances and loss of residual acoustic hearing. This study investigates the extent to which macrophage depletion by an orally administered CSF-1R specific kinase (c-FMS) inhibitor, PLX-5622, modulates the tissue response to CI and neural health.Materials and methods10-12-week-old CX3CR1+/GFP Thy1+/YFP mice on C57Bl6 background with normal hearing were fed chow containing 1200 mg/kg PLX5622 or control chow for the duration of the study. 7-days after starting the diet, 3-channel cochlear implants were implanted ear via the round window. Serial impedance and neural response telemetry (NRT) measurements were acquired throughout the study. Electric stimulation began 7 days post-CI until 28- days post-CI for 5 hrs/day, 5 days/week, with programming guided by NRT and behavioral responses. Cochleae harvested at 10-, 28- or 56-days post-CI were cryosectioned and labeled with antibody against α-smooth muscle actin (α-SMA) to identify myofibroblasts and quantify the fibrotic response. Using IMARIS image analysis software, the outlines of scala tympani, Rosenthal canal, modiolus and lateral wall for each turn were traced manually to measure region volume. Density of nuclei, CX3CR1+ macrophages, Thy1+ spiral ganglion neuron (SGN) numbers and ratio of volume of α-SMA+ space/volume of scala tympani were calculated.ResultsCochlear implantation in control diet subjects caused infiltration of cells, including macrophages, into the cochlea: this response was initially diffuse throughout the cochlea and later localized to the scala tympani of the basal turn by 56-days post-CI. Fibrosis was evident in the scala tympani adjacent to the electrode array. Mice fed PLX5622 chow showed reduced macrophage infiltration throughout the implanted cochleae across all timepoints. However, scala tympani fibrosis was not reduced relative to control diet subjects. Further, mice treated with PLX5622 showed increased electrode impedances compared to controls. Finally, treatment with PLX5622 decreased SGN survival in implanted and contralateral cochleae.DiscussionThe data suggest that macrophages play an important role in modulating the intracochlear tissue response following CI and neural survival.

Project description:Cochlear implants (CIs) allow individuals with profound hearing loss to understand speech and perceive sounds. However, not all patients obtain the full benefits that CIs can provide and the cause of this disparity is not fully understood. One possible factor for the variability in outcomes after cochlear implantation, is the development of fibrotic scar tissue around the implanted electrode. It has been hypothesised that limiting the extent of fibrosis after implantation may improve overall CI function, and longevity of the device. Currently, histology is often used to quantify the extent of intracochlear tissue growth after implantation however this method is labour intensive, time-consuming, often involves significant user bias, and causes physical distortion of the fibrosis. Therefore, this study aimed to evaluate x-ray micro computed tomography (μCT) as a method to measure the amount and distribution of fibrosis in a guinea pig model of cochlear implantation. Adult guinea pigs were implanted with an inactive electrode, and cochleae harvested eight weeks later (n = 7) and analysed using μCT, to quantify the extent of tissue reaction, followed by histological analysis to confirm that the tissue was indeed fibrotic. Cochleae harvested from an additional six animals following implantation were analysed by μCT, before and after contrast staining with osmium tetroxide (OsO4), to enhance the visualisation of soft tissues within the cochlea, including the tissue reaction. Independent analysis by two observers showed that the quantification method was robust and provided additional information on the distribution of the response within the cochlea. Histological analysis revealed that μCT visualised dense collagenous material and new bone formation but did not capture loose, areolar fibrotic tissue. Treatment with OsO4 significantly enhanced the visible tissue reaction detected using μCT. Overall, μCT is an alternative and reliable method that can be used to quantify the extent of the CI-induced intracochlear tissue response and will be a useful tool for the in vivo assessment of novel anti-fibrotic treatments.

Project description:BackgroundAdults with single sided deafness (SSD) have lost binaural function, which limits sound source localization, speech understanding in noise, and quality of life. For SSD patients, restoration of bilateral auditory input is possible only with a cochlear implant (CI). In this study, cortical auditory evoked potentials (CAEPs) and behavioral performance were measured in left-implanted (SSD-CI-L) and right-implanted (SSD-CI-R) patients before and after cochlear implantation. We hypothesized that improvements in behavioral performance would be accompanied by changes in CAEPs after cochlear implantation.DesignProspective longitudinal study.SettingTertiary referral center.MethodNine right-handed adult SSD CI patients participated in the study. CAEPs were recorded before cochlear implantation and at 6 and 12 months post-implantation. CAEPs were elicited using speech stimuli (/ba/) delivered in sound field at 70 dBA. Global field power (GFP) latency and amplitude were calculated for P1, N1 and P2 peaks at each test session. CAEP were analyzed at frontocentral (Cz) and temporal (P7, P8, T7 and T8) and mastoid electrodes (M1 and M2) contralateral to the CI ear. Behavioral measures (sentence recognition in noise, with and without spatial cues) were collected at the same test sessions as for CAEPs. Speech performance and CAEPs were also measured in a control group of normal-hearing (NH) subjects.ResultsWhile increased N1 amplitude was observed in the scalp potential maps for GFP and Cz for SSD-CI-L patients after implantation, the changes were not statistically significant. Peak CAEP amplitude at electrodes to contralateral to the CI ear increased after cochlear implantation for all SSD-CI patients, but significant increases were observed only for mastoid sites. Peak latencies for some components at temporal and mastoid sites remained significantly longer than for the NH control group, even after cochlear implantation. For SSD-CI-R patients, P2 peak amplitude for baseline GFP and Cz was significantly lower than for the NH control group. A significant improvement for speech understanding in noise was observed at 12 months post-implantation when speech was presented to the CI ear and noise to the non-implanted ear.ConclusionAfter cochlear implantation, speech understanding significantly improved when speech and noise were spatially separated. The increased N1 amplitude for SSD-CI-L patients and the increased bilateral activation for all SSD-CI patients may reflect cortical reorganization and restoration of binaural function after one year of experience with the CI. However, because of the limited number of SSD patients, significant changes in cortical activity after cochlear implantation were often difficult to observe.

Dataset Information

An Improved Technique of Subtotal Cochleoectomy for Removal of Intracochlear Schwannoma and Single-stage Cochlear Implantation.

Publications

An Improved Technique of Subtotal Cochleoectomy for Removal of Intracochlear Schwannoma and Single-stage Cochlear Implantation.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets