Cochlear implantation in Pendred syndrome

Abstract

Objective

The objective of this study was to examine the anatomical, audiological, and surgical factors that can affect the hearing outcome in Pendred syndrome cochlear implant recipients. Patients with Pendred syndrome represent challenging cochlear implant candidates, combining goiter, severe-to-profound hearing loss, and inner-ear dysplasias. The hearing outcome and further relevant parameters in such patients have not been adequately evaluated yet.

Material and methods

Retrospective study in a tertiary referral cochlear implant centre. Data of patients with Pendred syndrome, who had undergone cochlear implantation in the 10-year period 1999–2008, were evaluated.

Results

Five cochlear implant recipients with Pendred syndrome were identified, four unilateral and one bilateral. The average postoperative follow-up duration for these patients was 4.8 years. Enlarged vestibular aqueduct and Mondini dysplasia were the most common anatomical findings. Although these anatomical variances did not affect the electrode insertion, they prolonged the duration of the surgery. Cerebrospinal fluid gusher was the most common intraoperative complication. All patients enjoyed satisfactory hearing rehabilitation.

Discussion

Cochlear implantation is the proper method for optimal hearing rehabilitation in patients with Pendred syndrome. Although the precise pathogenetic mechanism and the genetic background of deafness in Pendred syndrome have not been completely understood, the preexisting hearing experience represents a positive factor for satisfying hearing outcome. The inner-ear malformations can cause mild surgical difficulties and extended surgery duration. The cochlear implant surgeon should be aware of these difficulties to avoid complications.     

Evaluation of the Digisonic® SP cochlear implant: patient outcomes and fixation system with titanium screws

Cochlear implants have revolutionized the way patients affected by severe hearing loss experience the world. Neurelec developed a fixation system with two titanium screws that requires no skull bone drilling.ObjectiveTo describe the outcomes and procedure-related details of a series of patients implanted with the Digisonic® SP cochlear implant.MethodThis retrospective study analyzed patients submitted to cochlear implant placement within a period of 18 months. All patients had postlingual hearing impairment. Data was collected from patient charts and standard questionnaires answered by the surgeons in charge of carrying out the procedures.ResultsThe six patients offered the Digisonic® SP cochlear implants were operated by experienced surgeons. The procedures took 95 to 203 minutes (mean = 135') to be completed, which is less time than what has been described for other fixation approaches. No complications were recorded and hearing improvement was satisfactory.ConclusionThe Digisonic® SP cochlear implant developed by Neurelec offered good audiological results for adult patients, shorter surgery time, and no surgical or postoperative complications.     

The reliability of hearing implants: report on the type and incidence of cochlear implant failures

Objectives: This study presents the data collected through a database on the type and incidence of cochlear implant device failures and major complications and quantifies the risk of failures across time based on the Association for the Advancement of Medical Instrumentation (AAMI) CI86:2017 standard.

Methods: Information on reliability of MED-EL cochlear implants was collected from the MED-EL complaint database between 2003 and2013. Explants were categorized and device reliability was calculated according to the AAMI CI86:2017 standard principles.

Results: Data were collected for 11662 devices (5462 children, 6200 adults). The mean duration of follow up was 46.16 months. The total failure rate for all devices and all subjects was 2.41%. Medical related explants (MRE) were significantly worse for children than for adults with the ceramic implants, C40+ (p?=?0.008) and PULSAR (p?=?0.020). Device failure explants (DFE) were significantly worse for children than for adults with all four devices in the study, the C40+ (p?<?0.001), PULSAR (p?<?0.001), SONATA (p?<?0.001), and CONCERTO (p?=?0.023). The mean annual failure rate for all subjects and devices was 0.63% (1.03% for children, 0.28% for adults). The mean annual failure rate was 0.90% for the C40+; 0.57% for the PULSAR; 0.46% for the SONATA; and 0.39% for the CONCERTO.

Conclusions: Compared to adults, children had significantly worse MRE and DFE due to a higher risk of head trauma and more vulnerable skull anatomy. Further, the authors conclude that the AAMI standard will ensure a more comprehensive and transparent evaluation of cochlear implant reliability in the future.     

Cochlear implant revision surgeries in children

IntroductionThe surgery during which the cochlear implant internal device is implanted is not entirely free of risks and may produce problems that will require revision surgeries.ObjectiveTo verify the indications for cochlear implantation revision surgery for the cochlear implant internal device, its effectiveness and its correlation with certain variables related to language and hearing.MethodsA retrospective study of patients under 18 years submitted to cochlear implant surgery from 2004 to 2015 in a public hospital in Brazil. Data collected were: age at the time of implantation, gender, etiology of the hearing loss, audiological and oral language characteristics of each patient before and after cochlear implant surgery and any need for surgical revision and the reason for it.ResultsTwo hundred and sixty-five surgeries were performed in 236 patients. Eight patients received a bilateral cochlear implant and 10 patients required revision surgery. Thirty-two surgeries were necessary for these 10 children (1 bilateral cochlear implant), of which 21 were revision surgeries. In 2 children, cochlear implant removal was necessary, without reimplantation, one with cochlear malformation due to incomplete partition type I and another due to trauma. With respect to the cause for revision surgery, of the 8 children who were successfully reimplanted, four had cochlear calcification following meningitis, one followed trauma, one exhibited a facial nerve malformation, one experienced a failure of the cochlear implant internal device and one revision surgery was necessary because the electrode was twisted.ConclusionThe incidence of the cochlear implant revision surgery was 4.23%. The period following the revision surgeries revealed an improvement in the subject's hearing and language performance, indicating that these surgeries are valid in most cases.     

Hyperbaric oxygen therapy as a therapeutic option in cochlear implants extrusion treatment in infected wounds

Abstract

Background: Cochlear implant extrusion as a result of infection is an uncommon, but serious complication, which can lead to implant removal as the ultimate solution.

Objectives: (1) to identify the incidence of cochlear implant extrusion and its causes, (2) to report our management of patients presenting skin complications after cochlear implant surgery (3) to propose new therapeutical options with hyperbaric oxygen therapy (HBOT).

Materials and methods: A retrospective analysis of medical documentation of 1250 patients who were operated on with cochlear implants in our department between 1993 and 2015. The medical charts of 25 patients were selected due to reported skin flap complications resulting in CI extrusion. Five of those patients were subsequently removed from the study because of no infection signs.

Results: Non-traumatic cochlear implant extrusion occurred in 1.6% of implanted patients, and secondary treatment was effective in 90% of all cases (18 of 20 patients). HBOT as additional treatment was applied in 9 patients.

Conclusions: Hyperbaric oxygen therapy can be considered as safe adjuvant treatment option in individual cases of proceeding with cochlear implant extrusion with signs of wound infection.

Significance: HBOT may contribute to reducing the need for cochlear implant explantation due to infectious skin flap complication.     

Postoperative Complications in implanted patients in the Cochlear Implant Program of Rio Grande do Norte - Brazil

Cochlear implant surgery is regarded as safe for the auditory rehabilitation of individuals suffering from profound/severe hearing loss. Complications may arise from the surgery. The complications of implant cochlear surgery reflect the operation complexity, the skill of the surgical team and the inherent risks of the procedure itself.AimTo establish and discuss the postoperative complications in implanted patients from the Cochlear Implant Program of Rio Grande do Norte - Brazil.Study designRetrospective analysis.Materials and methodsThis paper discusses the clinical records of 250 patients implanted between August 2000 to December 2008. All patients were implanted by the same surgeon. The postoperative complications were classified in minor as those that resolved with minimal or no treatment and major as those requiring additional surgery or hospitalization.ResultsIn our sample, 33 patients (13.2%) had postoperative complications. Minor complications affected 20 cases (8.0%), while major complications occurred in 13 cases (5.2%). Hematomas, device failures and infections had the highest clinical relevance.ConclusionThis review reinstates the safety of the surgical procedure in relation to the possible occurrence of postoperative complications and emphasizes the need for continuous surgeon education and training.     

The outcome of our modified double-flap technique for cochlear implantation: A case series of 342 consecutive patients

Abstract

Objectives

A lazy S-shaped postauricular incision with a modified double-flap technique has been used for cochlear implant surgery at our institution for the past 10 years. The postoperative surgical complications, morbidity, and outcome of this technique were evaluated.

Methods

A retrospective case review was conducted in a tertiary referral teaching center. A total of 342 patients with profound sensory hearing loss (173 female and 169 male subjects; age range, 11 months to 52 years) who underwent cochlear implantation using the double-flap postauricular transmastoid surgical approach during a 5-year period (2005 through 2009) with at least 5 years' follow-up were retrospectively evaluated. Postoperative wound complications were identified. Major complications included flap necrosis, wound infection requiring surgical intervention, and wound dehiscence with or without implant exposure. Swelling over the implant and superficial wound infections treated medically were considered minor complications. Other non-wound-related complications, surgical time, and number of electrodes inserted were also recorded.

Results

The surgical approach was accomplished in all the patients with four minor wound complications. The mean surgical time was 1.4 hours, and the mean time between surgery and the programming process was 2 weeks.

Conclusion

This modified double-flap technique was easy to perform and appeared to reduce the incidence of wound complications in cochlear implant surgery. It allowed programming of the implant after a shorter period of time.     

Cochlear implant fixation: are sutures really necessary?

The objective of this study was to evaluate retrospectively the risk of cochlear implant migration and complications related to the here presented alternative surgical fixation technique of the receiver/stimulator without any foreign body materials. Fixation of the implant was achieved by an “L-shaped” muscle-periosteal flap and an exactly shaped bony well. Between January 2006 and December 2009, 247 consecutive primary cochlear implantations have been performed with the described technique in the Department of Otorhinolaryngology, Head and Neck surgery of the University of Cologne (tertiary referral center). Devices from different manufacturers have been implanted. Implantation age ranged from 6 months to 78 years (mean age: 24.50 years). Follow-up time ranged from 12 to 60 months. Neither implant dislocations nor migrations were observed in our patients. In four very young children (1.6 %), additional suture fixation of the implant was performed. Postoperative complications, i.e. seroma or hematoma were observed in a total of six cases (2.4 %). The here presented surgical fixation technique is a sufficient and reliable way for fixation of cochlear implants independent of the device type.     

Exploring the experiences of teenagers with cochlear implants

Objectives: Teenage cochlear implant users’ perceptions of deafness, surgery, fitting of the device and life as a cochlear implant wearer were explored in order to gain a more comprehensive understanding of teenagers’ experiences of living with the device.

Methods: Semi-structured in-depth interviews were undertaken and analysed using thematic analysis. Ten teenagers aged 14–16 years with at least one cochlear implant were interviewed.

Results: Seven teenagers experienced great pre-operative anxiety and two reported significant post-operative pain. Four of the teenagers described a mismatch between their expectations and the disappointing reality of adjusting to the device. However, all the teenagers reported an enhanced sense of well-being as a result of being able to interact more easily with their world around them. The teenagers differed in the extent to which they identified with the hearing and deaf world.

Discussion: Despite the early challenges, over time the teenagers experienced many functional and psychosocial benefits. Most felt their lives were now easier as a result of the cochlear implant(s). They described complex, flexible identities.

Conclusions: By giving prominence to the teenagers’ voices this study has added new knowledge concerning their experience of surgery. The findings also more fully revealed the challenges of adjusting to the device and the impact of having a cochlear implant on the teenagers’ identities. Clinical recommendations are made to address the gaps in service highlighted by these findings.     

Remote programming of cochlear implants in users of all ages

Background: Remote programming for adult cochlear implant (CI) users is feasible, safe, and effective. Limited evidence, however, exists on if remote CI programming can also be productively done with paediatric CI users.

Aims/objectives: To assess the safety and feasibility of remote CI programming in CI users for all ages.

Materials and methods: Forty-six (25 children, 21 adults) experienced CI users were fit locally and remotely. The results of these two fitting sessions were compared in terms of safety, Impedance Field Telemetry (IFT), Maximum Comfortable Levels (MCL), Threshold Levels (THR), audiometry, fitting duration, and speech understanding.

Results: The subjects’ safety was not compromised during any of the fitting procedures. No significant difference was found for IFT, MCL, THR, audiometry, or speech understanding for either remote or local fitting. Remote fittings took slightly longer than local fittings when only the fitting time itself was measured.

Conclusions and significance: Remote follow-up fitting is as safe, feasible, and effective as local fitting for CI users of all ages. A more extensive adoption of remote fitting may allow many CI users greater access to clinics and therefore increased benefit from CI use.     

Clinical validation of percutaneous cochlear implant surgery: initial report

Objective: Percutaneous cochlear implant surgery consists of a single drill path from the lateral mastoid cortex to the cochlea via the facial recess. We sought to clinically validate this technique in patients undergoing traditional cochlear implant surgery. Study Design: Prospective clinical trial. Methods: After institutional regulatory board‐approved protocols, five ears were studied via the following steps. 1) In the clinic under local anesthesia, bone‐implanted anchors were placed surrounding each mastoid. 2) Temporal‐bone computed tomography (CT) scans were obtained. 3) On the CT scans, paths were planned from the lateral mastoid cortex, through the facial recess, to the basal turn of the cochlea both “manually” and “automatically” using computer software. 4) Customized microstereotactic frames were rapid‐prototyped to serve as drill guides constraining the drill to follow the appropriate path. 5) During cochlear implant surgery, after drilling of the facial recess, drill guides were mounted on the bone‐implanted anchors. 6) Accuracy of paths was assessed via intraoperative photodocumentation. Results: All surgical paths successfully traversed the facial recess and hit the basal turn of the cochlea. Distance in millimeters (average ± SD) from the midpoint of the drill to the facial nerve was 1.18 ± 0.68 for the “manual” path and 1.24 ± 0.44 mm for the “automatic” path and for the chorda tympani 0.986 ± 0.48 for the “manual” path and 1.22 ± 0.62 for the “automatic” path. Conclusions: Percutaneous cochlear implant access using customized drill guides based on preoperative CT scans and image‐guided surgery technology can be safely accomplished.     

Cochlear implantation in an animal model documents cochlear damage at the tip of the implant

IntroductionElectrocochleography has recently emerged as a diagnostic tool in cochlear implant surgery, purposing hearing preservation and optimal electrode positioning.ObjectiveIn this experimental study, extra-cochlear potentials were obtained during cochlear implant surgery in guinea pigs. The aim was to determine electrophysiological changes indicating cochlear trauma after cochleostomy and after electrode implantation in different insertion depths.MethodsNormal-hearing guinea pigs (n = 14) were implanted uni- or bilaterally with a multichannel electrode. The extra-cochlear cochlear nerve action potentials were obtained in response to acoustic stimuli at specific frequencies before and after cochleostomy, and after introduction of the electrode bundle. After the electrophysiological experiments, the guinea pigs were euthanized and microtomography was performed, in order to determine the position of the electrode and to calculate of the depth of insertion. Based on the changes of amplitude and thresholds in relation to the stimulus frequency, the electrophysiological data and the position obtained by the microtomography reconstruction were compared.ResultsCochleostomy promoted a small electrophysiological impact, while electrode insertion caused changes in the amplitude of extra-cochlear electrophysiological potentials over a wide range of frequencies, especially in the deepest insertions. There was, however, preservation of the electrical response to low frequency stimuli in most cases, indicating a limited auditory impact in the intraoperative evaluation. The mean insertion depth of the apical electrodes was 5339.56 μm (±306.45 – 6 inserted contacts) and 4447.75 μm (±290.23 – 5 inserted contacts).ConclusionsThe main electrophysiological changes observed during surgical procedures occurred during implantation of the electrode, especially the deepest insertions, whereas the cochleostomy disturbed the potentials to a lesser extent. While hearing loss was often observed apical to the cochlear implant, it was possible to preserve low frequencies after insertion.     

Simultaneous cochlear implantation in children: the Great Ormond Street experience

Abstract

Objectives

To analyse the surgical aspects and safety of bilateral simultaneous cochlear implantation in children.

Methods

A retrospective case series at a tertiary paediatric centre in the United Kingdom. Surgical times, analgesia and antiemetic use, and complications were analysed for the first 25 bilateral simultaneous cochlear implants performed at Great Ormond Street Hospital for Children between September 2007 and December 2009. These were compared with a consecutive group of sequentially implanted children whose second implant was performed during the same period.

Results

Total time for simultaneous implantation was significantly less than the cumulative time required for sequential implantation (P < 0.05). In addition, the number of paracetamol, non-steroidal anti-inflammatory, and antiemetic doses was significantly less for simultaneous implantation than for sequential implantation (P < 0.001). Furthermore, the number of doses of analgesia and antiemetic required for simultaneous implantation were no higher than for single-side surgery (P > 0.05). No difference in complication rates was seen between the groups.

Discussion

Bilateral simultaneous cochlear implantation in children is safe and results in a reduction in total theatre time when compared with the cumulative time required for sequential implantation. Simultaneous implantation also reduces total analgesia and antiemetic requirements and length of stay to levels comparable with single-side implantation.     

Accuracy of intraoperative electrophysiological testing in confirming correct cochlear implant electrode positions

Objective: To investigate the accuracy of intraoperative electrophysiological studies in detecting incorrectly positioned electrodes in cochlear implant surgery.

Study design: A retrospective chart review.

Setting: Tertiary referral centre.

Patients: In total, 104 consecutive patients with a mean age of 5 years underwent cochlear implant surgery at our centre between January 2012 and December 2013. All patients were implanted with Cochlear Nucleus Freedom implants.

Method: A retrospective study to compare intraoperative neural response telemetry (NRT), impedance and electrode position using Stenver’s transorbital plain X-ray view.

Results: Intraoperative electrophysiological tests for patients with Cochlear Nucleus Freedom implants showed 97% sensitivity and 100% specificity compared with postoperative X-ray imaging.

Conclusion: NRT results for the position of cochlear implants were very accurate when checked by X-ray imaging showing that this technique is sufficient in most cases. Stenver’s plain X-ray view is needed in complicated cases with abnormal NRT testing or difficult electrode insertion.     

Feasibility of hearing preservation for residual hearing with longer cochlear implant electrodes

Abstract

Background: Hearing preservation is thought to be achievable following atraumatic surgery with thin cochlear implant electrodes; therefore, the surgical approach and implant electrode design are crucial considerations.

Objective: To assess the feasibility of hearing preservation with long electrodes for patients meeting the criteria for conventional cochlear implantation.

Methods: One hundred and two patients (132 ears) who underwent cochlear implant surgery were analyzed. Inclusion criteria included measurable residual hearing in the low frequency before implantation and not meeting the criteria for electric acoustic stimulation (EAS).

Results: Of the 18 patients with residual hearing in the low frequency enrolled, 17 subjects (94.4%) retained low frequency hearing. A younger age at surgery tended to contribute to better hearing preservation than that observed in older patients. There was no clear trend regarding the influence of insertion depth angle of the electrode on hearing preservation.

Conclusion: It is possible to achieve hearing preservation in the lower frequency by the use of longer electrodes. This study underscores the importance of atraumatic surgery, even for patients with only limited residual hearing, and longer electrodes should be adopted for EAS.     

Cochlear implantation in early deafened,late implanted adults: Do they benefit?

Objectives: The aim of this study was to quantify the benefit gained from cochlear implantation in pre- or peri-lingually deafened patients who were implanted as adults Methods: This was a retrospective case-control study. Auditory (BKB/CUNY/3AFC/Environmental sounds), quality of life (GBI/HUI3) and cognitive (customized questionnaire) outcomes in 26 late implanted pre- or peri-lingually deafened adults were compared to those of 30 matched post-lingually deafened, traditional cochlear implant users.

Results: There was a statistically significant improvement in all scores in the study group following cochlear implantation. BKB scores for cases was 49.8% compared to 83.6% for controls (p=0.037). CUNY scores for cases was 61.7% compared to 90.3% for controls (p=0.022). The 3AFC and environmental sounds scores were also better in controls compared to cases but the difference was not statistically significant. Quality of life scores improved following implantation in cases and controls but the improvement was only statistically significant in the controls. There was a 7.7% non-user rate in the cases. There were no non-users in the control group.

Discussion: Early deafened,,late implanted patients can benefit audiologically from cochlear implantation and in this study the improvement in speech discrimination scores was greater than expected perhaps reflecting careful selection of patients. Nevertheless, audiological benefits are limited compared to traditional cochlear implant recipients with the implant acting as an aid to lip reading in most cases.

Conclusion: With careful selection of candidates, cochlear implantation is beneficial in early deafened, late implanted patients.     

Establishing the standard method of cochlear implant in Rongchang pig

Conclusions: In this investigation, a large mammal, Rongchang pigs were used to successfully establish a research platform for cochlear implant study on the routine use of it in clinic.

Objective: The aim of this study was to establish a standard method of cochlear implant in a large mammal—pig.

Methods: Rongchang pigs were selected, then divided into two groups: normal-hearing group (Mitf?+/+) and mutation group with hearing loss (Mitf ?/?). Cochlear implants were used and ABR and EABR were recorded. The implanted electrodes were observed by X-ray and HE stains.

Results: The success with cochlear implant and the best electrode position could be defined in all animals, the coiling of the cochlea reached 1.5–1.75 turns. Immediately after the operation of cochlear implants, the ABR threshold of the operated ear (right) could not be derived for each frequency at 120?dB SPL. Moreover, 7 days after surgery, the low-frequency ABR threshold of the operated ear (right) could be derived partly at 100?dB SPL, but the high-frequency ABR threshold could not be derived at 120?dB SPL. Immediately or 1 week after cochlear implants, the EABR threshold was 90?CL in the Mitf?+/+?group. This was obviously lower than the 190?CL in the Mitf ?/? group.     

Language and speech perception of young children with bimodal fitting or bilateral cochlear implants

Abstract

Objectives

This paper compares language development and speech perception of children with bimodal fitting (a cochlear implant in one ear and a hearing aid in the opposite ear) or bilateral cochlear implantation.

Methods

Participants were children enrolled in the Longitudinal Outcomes of Children with Hearing Impairment study. Language development was assessed at 3 years of age using standardized tests. Speech perception was evaluated at 5 years of age. Speech was presented from a frontal loudspeaker, and babble noise was presented either from the front or from both sides.

Results

On average, there was no significant difference in language outcomes between 44 children with bimodal fitting and 49 children with bilateral cochlear implants; after controlling for a range of demographic variables. Earlier age at cochlear implant activation was associated with better outcomes. Speech perception in noise was not significantly different between children with bimodal fitting and those with bilateral cochlear implants. Compared to normal-hearing children, children with cochlear implants required a better signal-to-noise ratio to perform at the same level, but demonstrated spatial release from masking of a similar magnitude.

Conclusions

This population-based study found that language scores for children with bilateral implants were higher than those with bimodal fitting or those with unilateral implants, but neither reached significance level.     

Surgical complications in 550 consecutive cochlear implantation

Cochlear implantation is a safe and reliable method for auditory restoration in patients with severe to profound hearing loss.ObjectiveTo describe the surgical complications of cochlear implantation.Materials and MethodsInformation from 591 consecutive multichannel cochlear implant surgeries were retrospectively analyzed. All patients were followed-up for at least one year. Forty-one patients were excluded because of missing data, follow-up loss or middle fossa approach.ResultsOf 550 cochlear implantation analyzed, 341 were performed in children or adolescents, and 209 in adults. The mean hearing loss time was 6.3 ± 6.7 years for prelingual loss and 12.1 ± 11.6 years for postlingual. Mean follow-up was 3.9 ± 2.8 years. Major complications occurred in 8.9% and minor in 7.8%. Problems during electrode insertion (3.8%) were the most frequent major complication followed by flap dehiscence (1.4%). Temporary facial palsy (2.2%), canal-wall lesion (2.2%) and tympanic membrane lesion (1.8%) were the more frequent minor complications. No death occurred.ConclusionThere was a low rate of surgical complications, most of them been successfully managed. These results confirm that cochlear implant is a safe surgery and most surgical complications can be managed with conservative measures or minimal intervention.