Complicaciones y fallos de la implantación coclear

The Risk of Meningitis After Cochlear Implantation: A Systematic Review and Meta-Analysis

OBJECTIVE

This study aims to estimate the rate of postoperative meningitis (both immediate and long-term) in patients following cochlear implants (CIs). It aims to do so through a systematic review and meta-analysis of published studies tracking complications after CIs.

DATA SOURCES

MEDLINE, Embase, and Cochrane Library.

REVIEW METHODS

This review was performed in line with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies tracking complications following CIs in patients were included. Exclusion criteria included non-English language studies and case series reporting <10 patients. Bias risk was evaluated using the Newcastle-Ottawa Scale. Meta-analysis was performed through DerSimonian and Laird random-effects models.

RESULTS

A total of 116/1931 studies met the inclusion criteria and were included in the meta-analysis. Overall, there were 112 cases of meningitis in 58,940 patients after CIs. Meta-analysis estimated an overall rate of postoperative meningitis of 0.07% (95% confidence interval [CIs], 0.03%-0.1%; I2  = 55%). Subgroup meta-analysis showed this rate had 95% CIs crossing 0% in implanted patients who received the pneumococcal vaccine, antibiotic prophylaxis, those with postoperative acute otitis media (AOM), and those implanted less than 5 years.

CONCLUSION

Meningitis is a rare complication following CIs. Our estimated rates of meningitis after CIs appear lower than prior estimates based on epidemiological studies in the early 2000s. However, the rate still appears higher than the baseline rate in the general population. The risk was very low in implanted patients who received the pneumococcal vaccine, antibiotic prophylaxis, received unilateral or bilateral implantations, developed AOM, those implanted with a round window or cochleostomy techniques, and those under 5 years.

Infected Cochlear Implant and Re-implantation in a Pediatric Case

Cochlear implant (CI) surgery is relatively safe, however reports of complications and failure following cochlear implant surgery are higher nowadays due to the increasing number of patients with CI. Herein, we report a case of infected cochlear implant 10 months after surgery. A three-year-six-month-old girl underwent right cochlear implantation for bilateral profound sensorineural hearing loss. From day one until six months after the surgery, it was uneventful and the wound healed well. However, at 10 months post-surgery, she presented with a chronic discharging wound over the previous surgical site. Despite being on IV antibiotics for six weeks and daily dressing, the wound over the implant site keep discharging and eventually the implant was removed two months later. She was later re-implanted with a cochlear implant on the same side at the age of five years 10 months old. Currently, she is showing good speech improvement with the right CI. Her aided hearing threshold is at 30-40 dB at all frequencies. Early diagnosis is crucial, and the proper course of action should be taken as soon as possible if implant failure is suspected. Prior to implant surgery, any potential risk factors that could lead to implant failure should be identified and addressed appropriately to reduce the risk of an infected cochlear implant.

A modified surgical technique for the Jarvik 2000 using a postauricular approach

The Jarvik 2000, with a postauricular cable, is a left ventricular assistance device with a driveline that is passed to the postauricular region subcutaneously. A titanium pedestal base that holds a 3-pin connector is fixed to the parietal bone, posterior to the auricle. Essentially, the device is fixed in the same position as a cochlear implant; however, the disadvantages include continuous mechanical stress on the cable by neck rotations, and the visibility of the apparatus. To improve such concerns, we adjusted the location of the pedestal of the lower parietal bone to just above the transverse sinus and closer to the mastoid process. To reach this point, the internal cable was passed through the retromastoid pathway commonly used in ventriculoperitoneal shunting. The thickness of the skull at this location is sufficient for safe fixation; however, preoperative evaluation by a neurosurgeon using CT is necessary.

Complications of Cochlear Implant Surgery: A Public Implant Centre Experience

Objectives:

To determine the prevalence of complications of cochlear implant surgery in children with congenital profound sensorineural hearing loss.

Methods:

This study retrospectively & consecutively reviewed charts of children who underwent cochlear implantation from July 2015 to July 2019 at Cochlear Implant Centre of Otolaryngology Department of Capital Hospital, Islamabad Pakistan. These included cases of both genders aged one to 12 years operated at least one year before the time of data collection. Basic demographic data, complications including major and minor complications and treatment received was noted and statistically analyzed using SPSS-23. Results were presented using descriptive statistics.

Results:

Current study included a sample of N=251 having a mean age of 4.05±2.15 years including 154(61.4%) males and 97(38.6%) females revealed a prevalence of complications of 16(6.4%) with 4(1.6%) major and 12(4.8%) minor complications. Wound infection and acute otitis media with frequency of 3(1.2%) each were the commonest complications, followed by , facial nerve twitching, tinnitus and vertigo, infection and extrusion; and device failure in 2(0.8%) each. However, there was no significant association of complications with age group and gender with P=0.344 and P=0.519 respectively.

Conclusion:

Present public sector implant program is characterized with a very low prevalence of complications of 16(6.4%) with 4(1.6%) major and 12(4.8%) minor complications. Wound infection and acute otitis media were the commonest complications.

Cochlear Implant Reliability: On the Reporting of Rates of Revision Surgery

The aim of this study was to determine the magnitude of the risks associated with cochlear implantation. Results from a pool of thirty clinical studies involving cochlear implantation in over 6300 children were obtained from an internet search. The relevant data were transformed to a common time base (patient time) to allow an evaluation of events following implantation. The main outcome measure was cumulative survival probability for all-cause revision surgery. Over 10 years this was estimated to be 0.71. Thus, at 10 years post-implantation close to 30% of children with unilateral implants will have undergone revision surgery. This figure is considerably greater than that commonly reported for overall revision rates and illustrates the importance of interpreting results with respect to the relevant time frame. When non and low-use is incorporated into the analysis the above figure rises to about 37% of children affected. The findings raise concerns about the information provided to both individuals and regulatory bodies regarding the risks associated with cochlear implantation. The consequences for bilateral implantation are apparent. Our recommendations are i) a full disclosure to parents and children of the true magnitude of the risks and ii) for a body with significant expertise in reliability and systems engineering, and no conflicts of interest, to play a major role in the regulatory management of this service.

Evaluation of vaccination coverage in cochlear implant patients at a referral hospital in Northern Spain

BACKGROUND AND OBJECTIVE

The risk of bacterial meningitis increases in cochlear implant patients. Therefore, pneumococcal, influenza and Haemophilus influenzae type b vaccination is indicated in this group. The aim of this study was to determine compliance with the vaccination calendar in patients implanted in a referral hospital.

MATERIALS AND METHODS

Patients with cochlear implant operated between 2005 and 2015 were included. Vaccine coverage for seasonal influenza, Haemophilus influenzae type b and pneumococcal conjugate 13-serotypes and pneumococcal polysaccharide 23-serotypes was evaluated. The sample was divided into 2 age groups (<14 years and≥14 years). A univariate and bivariate analysis was performed.

RESULTS

Of the 153 patients studied (28.01% 0-13 years old and 71.9%≥14), only 2 (5.71%) had 100% adherence to the vaccination schedule, while 65.71% had compliance of 50% or less. Overall, vaccination coverage against the sequential pneumococcal pattern was 48.57%. The paediatric population exceeded 90% coverage for the vaccine against Haemophilus influenzae type b and pneumococcal conjugate 13-serotypes while in those over 14 years of age it barely exceeded 50%. Influenza coverage was less than 40%. An inverse correlation was obtained between age and compliance, although not statistically significant.

CONCLUSIONS

Vaccination coverage in patients with cochlear implant is lower than expected. Close collaboration between Otolaryngology departments and the Vaccination Units is proposed as the main strategy for improvement.

Evaluation of the Facial Recess and Cochlea on the Temporal Bone of Stillbirths regarding the Percutaneous Cochlear Implant

Introduction  The literature shows that there are anatomical changes on the temporal bone anatomy during the first four years of life in children. Therefore, we decided to evaluate the temporal bone anatomy regarding the cochlear implant surgery in stillbirths between 32 and 40 weeks of gestational age using computed tomography to simulate the trajectory of the drill to the scala timpani avoiding vital structures. Objectives  To measure the distances of the simulated trajectory to the facial recess, cochlea, ossicular chain and tympanic membrane, while performing the minimally invasive cochlear implant technique, using the Improvise imaging software (Vanderbilt University, Nashville, TN, US). Methods  An experimental study with 9 stillbirth specimens, with gestational ages ranging between 32 and 40 weeks, undergoing tomographic evaluation with individualization and reconstruction of the labyrinth, facial nerve, ossicular chain, tympanic membrane and cochlea followed by drill path definition to the scala tympani. Improvise was used for the computed tomography (CT) evaluation and for the reconstruction of the structures and trajectory of the drill. Results  Range of the distance of the trajectory to the facial nerve: 0.58 to 1.71 mm. to the ossicular chain: 0.38 to 1.49 mm; to the tympanic membrane: 0.85 to 1.96 mm; total range of the distance of the trajectory: 5.92 to 12.65 mm. Conclusion  The measurements of the relationship between the drill and the anatomical structures of the middle ear and the simulation of the trajectory showed that the middle ear cavity at 32 weeks was big enough for surgical procedures such as cochlear implants. Although cochlear implantation at birth is not an indication yet, this study shows that the technique may be an option in the future.

One-stage coclear implantation via a facial recess approach in children with otitis media with effusion

Objective

To investigate surgical indications, operative techniques, complications and auditory and speech rehabilitation for cochlear implant (CI) in children with otitis media with effusion (OME).

Material and methods

This is a retrospective review of records of 24children with bilateral profound sensorineural hearing loss and OME who were implanted during January 2011 to November 2014 in the Department of Otorhinolaryngology and Head and Neck Surgery at the PLA Hospital, using one-stage implantation via the facial recess approach and round window insertion. The incus was removed in 8 cases during the implantation procedure. Local infiltration of dexamethasone and adrenaline in the middle ear was also performed. Postoperative complications were examined. Preoperative and postoperative questionnaires including Categories of Auditory Performance (CAP), Speech Intelligibility Rating (SIR), and the Meaningful Auditory Integration Scale (MAIS) were collected.

Results

All electrodes were implanted successfully without any immediate or delayed complications. Inflammatory changes of middle ear mucosa with effusion were noted in all implanted ears. The scores of post-implant CAP and SIR increased significantly in all 24 cases (t = −25.95 and −14.09, respectively for CAP and SIR, p < 0.05).

Conclusions

One-stage CI via the facial recess approach with round window insertion is safe and effective in cochlear implant candidates with OME, as seen in the 24 children in our study who achieved improved auditory performance and speech intelligibility after CI.

Outcomes of cochlear reimplantation in adults

OBJECTIVE

To determine the indications for, and auditory outcomes following, cochlear reimplantation in adults and investigate factors influencing outcome.

STUDY DESIGN

Retrospective case series.

SETTING

Cochlear implant program in a tertiary care hospital.

PATIENTS

Thirty adults (32 ears) who have undergone cochlear reimplantation in the ipsilateral ear.

INTERVENTION(S)

Explantation and reimplantation of cochlear implant.

MAIN OUTCOME MEASURE(S)

Speech discrimination as measured using Bamford-Kowal Bench sentence testing in quiet (BKBq) and noisy (BKBn) environments.

RESULTS

Best BKBq improved from 58.5% to 71.4% (p = 0.0242), and BKBn improved from 60.9% to 67.2% (p = 0.826) after reimplantation. Device failure was the most common indication for reimplantation. There was no significant difference in failure rate or outcome between implant manufacturers. The mean time to reimplantation was 4.7 years, and this was not related to auditory outcome. Otosclerosis and Ménière's disease may predispose to a worse auditory outcome after reimplantation.

CONCLUSION

Cochlear reimplantation does not have a detrimental effect on auditory outcomes and in some cases results in improved speech perception.

Acute Mastoiditis in Children with Cochlear Implants

Objective

Acute mastoiditis is an uncommon but challenging condition when it occurs in children with cochlear implant. The literature is scarce as to the management of this condition with regards to explantation. The objective of the study is to determine the need for explantation in patients with cochlear implants who suffer from acute mastoiditis.

Data Sources

Online medical databases—PubMed, Ovid Medline, Ovid Medline in process, Embase, Cochrane Library, CINAHL, Biosis, Google Scholar, and Scopus.

Review Methods

A systematic review of all publications addressing the treatment of mastoiditis in cochlear implant children prior to November 2013 was conducted. Data were collected from online medical databases—PubMed, Ovid Medline, Ovid Medline in process, Embase, Cochrane Library, CINAHL, Biosis, Google Scholar, and Scopus. The review was performed in 3 phases; an initial screening review of abstracts was performed, followed by a detailed review of full articles based on inclusion and exclusion criteria, and lastly a final review to extract data from selected articles.

Results

Twelve articles were found eligible for this systematic review including a total of 43 patients. Subperiosteal abscess was present in 14.3%. All patients received intravenous antibiotics as an initial treatment, and if needed, surgical intervention was performed. Only 1 patient required explantation (2.3%).

Conclusion

Prompt, aggressive medical and if needed surgical therapy can help in saving the implant and result in a favorable outcome.

Rates of revision and device failure in cochlear implant surgery: a 30-year experience

OBJECTIVES/HYPOTHESIS

To characterize revision cochlear implant surgery and quantify rates of revision and device failure.

STUDY DESIGN

Retrospective review of 235 cases of revision cochlear implant surgery performed at the Sydney Cochlear Implant Center over a period of 30 years, between January 1982 and June 2011.

METHODS

Patient demographics and characteristics of revision surgery were retrospectively extracted from a centralized database. Analyses of overall and cumulative rates were performed.

RESULTS

During the study period, 2,827 primary cochlear implantations were performed in 2,311 patients, with 201 primary implants in 191 patients of this cohort (109 children and 82 adults) undergoing 235 revision surgeries. The most common indication for revision surgery was device failure (57.8%), followed by migration/extrusion (23.4%), infection/wound complication (17.0%), and poor outcome/secondary pathology (6.4%). The majority of revision surgeries were reimplantations. Overall revision and device failure rates were 8.3% and 4.8%, respectively. The cumulative revision rate for primary implants at all ages increased linearly by 1% per year. The cumulative revision rate was significantly higher in children, and decreased with more recently performed implantations and with newer generations of implants.

CONCLUSIONS

The cumulative revision rate for primary implants suggests an ongoing linear relationship between the time of postprimary implantation and the need for revision surgery. We have formed an evidence base that characterizes the nature and frequency of revision surgery in a high-volume setting, allowing clinicians to effectively counsel prospective patients and clinics to understand the burden of revision surgery and device failure.

Cerebrospinal fluid gusher in cochlear implantation

OBJECTIVES

To share our experience of cerebrospinal fluid (CSF) gusher in cochlear implantation.

METHODS

Demographic, radiological, and surgical results of patients with CSF gusher in 523 consecutive cochlear implant recipients including children and adults as well as our management technique were evaluated and a review of the literature has been included.

RESULTS

Fifteen (2.87%) cases had CSF gusher. Two patients (13.3%) were adults with post-lingual hearing loss and the rest 12 (86.7%) were children with congenital hearing loss. Twelve patients (80%) had various types of inner ear malformation. Three patients (20%) had no predictable risk of CSF gusher from history or pre-operative imaging. In all patients, CSF gushers were controlled with our technique of packing the electrode entrance site with no additional measures.

CONCLUSION

CSF gusher may occur with post-lingual hearing loss and in children with apparently unremarkable imaging and history. Thus, surgeons should always be ready to manage it. Management of CSF gusher can be mainly performed during the initial surgery by precise tight packing of the electrode entrance site. Furthermore, non-surgical or surgical measures are rarely required to stop a persistent leak. Our results show that our management technique may be recommended as well.

Digisonic SP® Binaural cochlear implant: the coronal tunneled approach

Cochlear implants represent a significant breakthrough in the treatment of hearing loss. Evidence indicates bilateral hearing brings significant benefits to patients, particularly when binaural hearing is offered.

Objective

To describe the first case of implantation of a Digisonic SP^® Binaural Neurelec device in Brazil (the third implant placed in the Americas, after Mexico and Colombia) and the chosen surgical approach.

Method

Description of a surgical approach.

Results

The procedure was successfully completed.

Discussion

The squelch effect, binaural summation, location of the sound source, and the shadow effect of the head are listed among the reasons to explain the superiority of binaural rehabilitation. Cost of treatment must be considered in the development of public health policies.

Conclusion

The cost of cochlear implants has been one of the main impediments to bilateral rehabilitation. The Digisonic SP^® Binaural Neurelec device addresses this issue and exposes patients to less risk through a minimally invasive implantation procedure.

Endocochlear inflammation in cochlear implant users: case report and literature review

OBJECTIVES

Cochlear implantation is a relatively safe procedure with a low complication rate. The overall rate of complications among cochlear implant patients ranges from 6% to 20%. Major complications are those that are life-threatening or require surgery, whereas minor complications are those that can be medically treated. Nonetheless, certain complications, even if highly rare, may require specific investigations and treatments. Among these rare complications are those with endocochlear involvement, such as cochleitis or labyrinthitis, with fibrosis or ossification that could lead to explantation. The aims of the present study were to report a particular case of post-operative cochleitis and to review the rate of complications after cochlear implantation, emphasising those conditions with proven endocochlear involvement.

METHODS

We refer to the case of an eight-year-old Italian boy affected by the sudden onset of headache, ipsilateral otalgia and facial paresis, who presented to our clinic for inexplicable worsening of the performance of his implant and his residual hearing, six years after surgery. A complete investigation including (clinical history, routine, autoimmune and serological blood tests, electrophysiological measurements from the cochlear implant and neuroimaging) was performed and is herein described. Additionally, a comprehensive review of the literature was conducted using internet search engines; 274 papers were selected, 88 of which were best suited to our purposes.

RESULTS

In our case, the progression of the symptoms and the performance decrement required explantation, followed by a complete recovery. Reviewing the literature revealed only three reports concerning cases of proven endocochlear phlogosis that required revision surgery. Wound swelling/infection and vertigo remain the two most common complications of cochlear implantation. Failure of the device is the third most frequent complication (10.06% of all complications and 1.53% of cochlear implantations). Other rare conditions (such as granulating labyrinthitis with cochlear fibrosis, ossification and erosion, silicone allergy and the formation of a biofilm around the internal device) are possible and unpredictable. Although rare (approximately 1%), such cases may require explantation.

CONCLUSIONS

Despite efforts by both surgeons and manufacturers, device-related and surgical complications still occur. These and other rare conditions demand specific management, and their frequency may be underestimated. Further studies are needed to assess more realistic rates of complications and devise more efficient strategies for early diagnosis and treatment.

Comparison of complications by technique used in cochlear implants

INTRODUCTION

Complications are a very sensitive indicator of the usefulness of a surgical technique. In cochlear implant surgery, there are 3 principal approaches: the classic approach uses the facial recess (FR), the suprameatal approach (SMA) does not require mastoidectomy and uses the creation of a tunnel over the facial nerve to enter the middle ear, and the endomeatal approach (EMA) is based on the completion of a groove in the posterior wall of external auditory canal.

MATERIAL AND METHODS

A multicentre review of 208 patients with cochlear implants, comparing the different techniques. The complications were classified into major and minor.

RESULTS

Among the 208 implanted patients, 10.5% (22 of 208) had complications. Of these, 2.88% (6 of 208) were major complications and 7.69% (16 of 208) were minor complications. Comparing the results obtained by the different approaches, the FR technique had the lowest rate of major complications (1.1%), followed by the EMA technique with 2.38% and SMA with 3.75%. As for minor complications, operations in the SMA group had the lowest rate (6.25%), followed by the EMA group (7.14%) and the group operated on using the FR technique presented the highest (10%).

CONCLUSIONS

The 3 techniques described show very similar rates of complications. Consequently, we can conclude that they are safe and are alternatives.

Foreign body reaction after cochlear implantation

Cochlear implantation is a widely accepted, safe procedure for patients with severe to profound sensorineuronal hearing loss. While complications are rare, revision surgeries are required for complications like device failure, misplaced electrode, flap necrosis, and wound infection. Foreign body reaction is a rare complication following cochlear implantation. We experienced a case of foreign body reaction after cochlear implantation treated by device removal. Foreign body reaction has to be considered as one of several causes in cochlear implantation cases that show symptoms mimicking recurrent wound infection or delayed extrusion. We report a case of foreign body reaction with a literature review.