Rapidly progressive bilateral postmeningitic deafness in children: Diagnosis and management

ObjectivesTo determine the diagnostic approach to severe or profound bilateral postmeningitic deafness and to propose management guidelines.Material and methodsA retrospective review of five patients (two adolescents and three infants) with rapidly progressive severe bilateral deafness following an episode of meningitis managed between 2004 and 2010.ResultsThe two adolescents presented Neisseria meningitidis meningitis and the three infants presented Streptococcus pneumoniae meningitis. Acquired bilateral deafness was diagnosed by audiometry an average of 68.8 days (range: 9–210) after the episode of meningitis. Behavioural audiological testing, adapted to age and state of health, was performed in all patients. Deafness was confirmed by Auditory Brainstem Response tests. All five patients were assessed by computed tomography (CT) and magnetic resonance imaging (MRI) within ten days. T2-weighted MRI sequences showed endolymph changes in four patients. CT scan demonstrated ossification in only one patient. Bilateral cochlear implant was performed in all patients, with complete electrode array insertion for eight implants and partial insertion for two implants (20 and 21 out of 22 electrodes inserted). Good results were obtained with cochlear implants in four cases.ConclusionsBilateral deafness can occur immediately or several months after bacterial meningitis, regardless of the micro-organism responsible, justifying screening by behavioural audiological testing adapted to age for two years following bacterial meningitis. Auditory Brainstem Response testing can confirm audiometric findings. When severe or profound bilateral deafness is observed, MRI must be performed urgently to detect endolymph inflammation or ossification. Early bilateral cochlear implantation is recommended in the presence of ossification.     

Evaluación de las coberturas de vacunación en pacientes con implante coclear de un hospital de referencia del norte de España

Background and objectiveThe 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 methodsPatients 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.ResultsOf 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.ConclusionsVaccination 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.     

Implantation of the common cavity malformation may prevent meningitis

Abstract

Objectives and importance

Children with certain congenital malformations of the inner ear, including those with a common cavity defect, have a higher incidence of spontaneous cerebrospinal fluid (CSF) leak and resulting meningitis. However, they may also benefit from cochlear implantation. We suggest that surgical management may be possible that both prevents meningitis and provides hearing rehabilitation during the same procedure.

Clinical presentation

A 2-year-old girl with bilateral common cavity defects who had previously undergone cochlear implantation developed contralateral CSF leak resulting in meningitis.

Intervention

After resolution of the infection, cochlear implantation was performed at the same time as definitive CSF leak repair. Simultaneous cochlear implantation and repair of the CSF leak successfully decreased the chance of recurrent meningitis in this case. She has been deriving hearing benefit from the bilateral implants.

Conclusion

This case suggests a role for cochlear implantation to be combined with simultaneous CSF leak repair in children with a cochlear malformation. Furthermore, bilateral cochlear implantation at an early age may be warranted in these patients before CSF leaks and meningitis have occurred.     

Double challenge: cochlear implantation in the only hearing ear with progressive hearing loss following meningitis and vestibular dysfunction after implantation

ObjectiveVestibular dysfunction associated with cochlear implantation is rare. It is usually seen in patients with otosclerosis due to spread of electrical activity throughout the demineralized bone. A 17-year old female with progressive hearing loss 2 years after meningitis and vestibular dysfunction in the implanted ear is presented in this study.FindingsThe patient had mild hearing loss in the right ear and total hearing loss on the left side because of complete ossification of the cochlea following meningitis. She had to have cochlear implantation in the right ear because of progression of hearing loss. She had successful implantation but she experienced vestibular dysfunction following activation of cochlear electrodes. Closure of two electrodes caused disruption of auditory programming. Then the patient was subjected to long term vestibular rehabilitation program.ConclusionTiming for implantation before the completion of cochlear ossification is crucial not to miss the chance for hearing restoration. However, difficulties in hearing rehabilitation due to extensive ossification can be doubled by vestibular problems triggered by stimulation of the vestibular nerve by cochlear electrodes. Attempts to reduce the balance problem will complicate auditory programming. Vestibular rehabilitation for long term helps to carry on hearing progress.     

Audiovestibular neuropathy in an immunocompetent man with cryptococcal meningitis

IntroductionCryptococcus spp. is a fungus responsible for 600,000 deaths per year worldwide, mainly in immunosuppressed subjects. However, 20% of cases occur in immunocompetent subjects. Neuropathic disorders involving the auditory nerve have been reported, but vestibular disorders have never been described in detail. We report the case of an immunocompetent man, who presented audiovestibular disorders leading to a diagnosis of cryptococcal meningitis.Case reportA 39-year-old man was referred for balance disorders and right sensorineural hearing loss. He presented right vestibulo-saccular impairment and bilateral absence of auditory brainstem responses. Brain MRI was suggestive of cryptococcal meningitis. A cystic lesion in the right flocculus compressed the vestibulocochlear nerve. During monthly follow-up, pure tone audiometry gradually improved and speech audiometry in silence returned to normal. Partial resynchronization of the auditory afferent pathways was observed only on the contralateral side to vestibulocochlear nerve compression, while complete recovery of saccular function was observed.DiscussionCryptococcal meningitis in immunocompetent subjects may be accompanied by lesions of the auditory and vestibular afferent pathways. Recovery of hearing and balance was observed in response to medical treatment and early vestibular rehabilitation.     

Auditory performance after cochlear reimplantation

AimThe aim of this study was to evaluate the impact of cochlear reimplantation (CR) on hearing performance in children and adults with severe to profound hearing loss.Material and MethodsRetrospective observational study.ObjectivesThe main objective of this study was to determine whether there was a difference in hearing performance before and after CR. Secondary objectives were to analyze reasons for CR; to assess correlations between auditory performance and complete electrode reinsertion during CR, age, gender, explantation-to-CR interval, and interval between first implantation and CR; and to assess difference in APCEI score and the French evaluation protocol for implanted patients before and after CR.ResultsComparison of speech perception scores before and after explantation-reimplantation showed no significant difference (P > 0.005) at 1 year or at 2 years after CR. In 80% of cases, reimplantation was due to hard implant failure. In other cases, it was undertaken for soft failure (diminished performance but no abnormalities on integrity testing) (8%), medical reasons (6%), or undetermined reasons (6%). There was no significant correlation between auditory performance at 1 or 2 years and complete or incomplete reinsertion of electrodes, age, gender, explantation-to-CR interval, or interval between first implantation and CR (P > 0.005). For the adult subgroup, the French evaluation protocol scores did not differ after reimplantation (P = 0.62). Likewise, for the child sub-group, APCEI and CAP results did not deteriorate after reimplantation.ConclusionReimplantation had no negative impact on hearing and speech perception, but provided performance equivalent to or better than after initial implantation.     

Cochlear implantation of solid organ transplant patients receiving immunosuppressive therapy

ObjectiveTo evaluate the incidence of infectious complications and healing problems in cochlear implant (CI) patients receiving immunosuppressive therapy following solid organ transplant.Study designIRB-approved retrospective chart review of implanted patients.SettingTertiary care children's hospital.MethodsSeven patients of the more than 1000 implanted during the time period between 1991 and 2014 underwent cochlear implantation while on immunosuppressive therapy after having received a solid organ transplant. Their charts were reviewed for demographic and medical information pre- and post-implantation. The 4 males and 3 females ranged in age at CI from 2.4 to 18.8 years, with a mean of 9.0 years. Postimplant follow-up averaged 3.9 years (range: 0.1–13.1). Main outcome measures were occurrence of wound healing, infectious complications, whether open-set word recognition was achieved, and communication mode(s).ResultsNo wound infections or delayed healing, mastoiditis, or bacterial meningitis occurred after cochlear implantation. All seven patients had received at least one pneumococcal vaccination prior to implantation. Five of 6 (83%) developed open-set speech perception, of whom 4 (67%) use only oral communication.ConclusionIn our series of patients receiving immunosuppressive therapy following solid organ transplantation, none developed wound healing or infectious complications after cochlear implantation. History of solid organ transplantation alone should not be a contraindication to cochlear implant candidacy which would deprive the child of the potential benefits of hearing, including language development.     

Case report: Staphylococcus aureus biofilm formation on an explanted cochlear implant demonstrated using an ultrasonication technique

Abstract

Relevance

Biofilm forming microorganisms are responsible for the infection of a number of different indwelling medical devices including cochlear implants. The current definitive technique for proving biofilm infection is the use of scanning electron microscopy that is expensive and of limited availability.

Clinical presentation

A persistently infected cochlear implant was explanted. At operation it was surrounded by a fibrous capsule containing a glue-like substance, characteristic of biofilm formation that yielded Staphylococcus aureus after ultrasonication of the device.

Technique

The explanted cochlear implant was placed in a nutrient broth in an ultrasonic water bath. The implant was ultrasonicated for 5 minutes and the broth cultured on blood agar, incubated aerobically and anaerobically for 48 hours, and then incubated in air on Maconkey agar for 24 hours. This produced a heavy, confluent growth of S. aureus, in contrast to previous aspirates from a blister that lay over the infected implant that grew a coliform organism and Pseudomonas sp.

Conclusion

Ultrasonication is a widely available and relatively inexpensive technique that can be used to improve the recovery of biofilm-associated organisms from explanted cochlear implants.     

Reading skills in Persian deaf children with cochlear implants and hearing aids

ObjectivesReading skills are necessary for educational development in children. Many studies have shown that children with hearing loss often experience delays in reading. This study aimed to examine reading skills of Persian deaf children with cochlear implant and hearing aid and compare them with normal hearing counterparts.MethodThe sample consisted of 72 s and third grade Persian-speaking children aged 8–12 years. They were divided into three equal groups including 24 children with cochlear implant (CI), 24 children with hearing aid (HA), and 24 children with normal hearing (NH). Reading performance of participants was evaluated by the “Nama” reading test. “Nama” provides normative data for hearing and deaf children and consists of 10 subtests and the sum of the scores is regarded as reading performance score.ResultsResults of ANOVA on reading test showed that NH children had significantly better reading performance than deaf children with CI and HA in both grades (P < 0.001). Post-hoc analysis, using Tukey test, indicated that there was no significant difference between HA and CI groups in terms of non-word reading, word reading, and word comprehension skills (respectively, P = 0.976, P = 0.988, P = 0.998).ConclusionConsidering the findings, cochlear implantation is not significantly more effective than hearing aid for improvement of reading abilities. It is clear that even with considerable advances in hearing aid technology, many deaf children continue to find literacy a challenging struggle.     

Cochlear helix and duct length identification – Evaluation of different curve fitting techniques

Objective: Within the field of cochlear implantation (CIs), the role of utilizing patient-specific cochlear anatomy for choosing the optimal implant electrode is becoming increasingly important. Unfortunately, performing detailed anatomical measurements of a cochlea using clinical imaging data is rather time consuming and hence difficult to implement into the clinical routine. In order to accelerate clinical cochlear anatomy evaluations, previously developed mathematical models can be adjusted to the patient-specific anatomy by measuring just a few overall cochlear dimensions. However, the accuracy of model-based cochlear anatomy estimations is unclear, and incorrect evaluations may lead to false conclusions regarding the suitability of specific implant electrodes.

Methods: Based on 10 cochleae, an error evaluation of various commonly used curve fitting approaches for cochlear shape and duct length approximation was conducted. Spline tracings of the cochlear contours were used as reference values for the various approximations.

Results: Parameterized average cochlear helix models and two of five analytical approaches were found to be suitable for reconstructing the cochlear helical shape and estimating its length.

Discussion: Spline curve reconstructions are the most accurate and reliable method for assessing patient-specific cochlear geometry, especially in the case of anatomical irregularities. The most accurate results within the group of model-based evaluations still resulted in mean overall cochlear length deviations of approximately 5%.

Conclusion: Spline curve reconstructions appear to be the best option for anatomical diagnostics in clinical practice. Retrospective studies can be performed to further evaluate model-based evaluations.     

Optimizing pneumococcal vaccination for paediatric cochlear implant recipients using the cochlear implant pneumococcal vaccination flowchart

Abstract

Introduction

Cochlear implant recipients are known to be at an increased risk of meningitis. It is routine practice to check that pneumococcal vaccinations have been received prior to surgery. Recent changes in United Kingdom national guidelines mean that children who were previously thought to be fully immunized may in fact not be optimally protected. We present a simple, robust audit tool that can be used in both primary care and tertiary centres to identify those children at risk.

Methods

The pneumococcal immunization status of 63 paediatric cochlear implant recipients was assessed using a unique and comprehensive flowchart-style audit tool. The data collected included age at implantation, details of previous immunizations, and whether or not further vaccinations were required.

Results

Fifty-four per cent of children were not optimally immunized prior to implantation. Seventy per cent of children required further vaccinations following surgery. The commonest reason for an incomplete immunization history was failure to administer the 23-valent vaccine after the second birthday.

Conclusion

The pneumococcal immunization schedule for high-risk children is complicated and nationally available guidance can be difficult to interpret. There are multiple types of vaccines and their use is not standardized across the UK. Cochlear implant programmes may find that a large proportion of their patients are in fact not optimally vaccinated, particularly in light of recent changes in the national guidelines. Our audit tool allows health professionals, in both primary care and implant centres, to accurately assess the status and immunization requirements for both new and old patients.     

Immediate activation after cochlear implantation: Preliminary Study

ObjectiveTo assess the feasibility of immediate activation of cochlear implants.Material and methodsA retrospective study compared speech audiometry results at 6 months post-implantation, implant fitting data and complications, on Student test, between 19 patients receiving day-1 implant activation (immediate activation: IA) and 10 patients with activation at 2 weeks (classical activation: CA).ResultsMean speech comprehension, using Fournier bisyllabic word lists at 60 dB 6 months after implantation, was 61.58% in IA and 71% in CA (P > 0.05). Mean intelligibility thresholds for 50% word-recognition were respectively 39.74 dB and 36.5 dB (P > 0.05). Speech audiometry results at 6 months were not affected by immediate versus classical activation. Comfort-level settings at 1 month in IA were not significantly different (Student test: P > 005) from intraoperative neural response thresholds: i.e., were practically stable. One IA patient required delayed activation at 1 month because of hematoma interfering between the external and internal parts of the implant. There were no other complications. The mean number of fitting sessions during the first year was 6.05 in the IA group and 6.55 in the CA group (P > 0.05).ConclusionGiven certain precautions during follow-up, immediate activation after cochlear implantation was feasible, and did not impair audiometric results.     

Tone and sentence perception in young Mandarin-speaking children with cochlear implants

ObjectivesThe purpose of this study was to examine the outcomes of cochlear implantation in young children in terms of (1) perception of lexical tones in quiet, (2) perception of sentences in quiet and in noise, (3) the effects of five demographic variables (i.e., preoperative hearing level, age at implantation, duration of cochlear implants use, maternal educational level, and whether a child underwent a hearing aid trial before implantation) on lexical tone perception and sentence perception, and (4) the relationship between lexical tone perception and sentence perception.Methods96 participants, aged from 2.41 years to 7.09 years, were recruited in mainland China. The children exhibited normal cognitive abilities and received unilateral implants at an average age of 2.72 years, with ages ranging from 0.69 to 5 years of age.ResultsThe mean score for tone identification was 77% (SD = 13%; chance level = 50%). Tone 2/tone 3 was the most difficult tone contrast to identify. Children with a longer duration of CI use and whose mothers had more years of education tended to perform better in sentence perception in quiet and in noise. Having undergone a hearing aid trial before implantation and more residual hearing were additional factors contributing to better sentence perception in noise. The only demographical variable that related to tone perception in quiet was duration of CI. In addition, while there was a modest correlation between tone perception and sentence perception in quiet (r_s = 0.47, p < 0.001), the correlation between tone perception in quiet and sentence perception in noise was much weaker (r_s = −0.28, p < 0.05).ConclusionsThe findings suggested that most young children who had been implanted before 5 years of age and had 1–3 years of implant use did not catch up with their aged peers with normal hearing in tone perception and sentence perception. The weak to moderate correlation between tone perception in quiet and sentence perception might imply that the improvement of tone perception in quiet may not necessarily contribute to sentence perception, especially in noise condition.     

The influence of obesity on operating room time and perioperative complications in cochlear implantation

ObjectiveThe rising incidence of obesity in the United States is associated with increased healthcare expenditures and resource allocation. Obesity has been associated with prolonged operating times during surgical procedures. The primary objective of this study is to compare body mass index (BMI) to length of surgery during cochlear implantation.MethodsA retrospective case control study from a tertiary academic referral center was performed. Patients included were adults who underwent primary, single-sided cochlear implantation with documented BMI and operating room (OR) times from January 2009 to July 2015. The following data were collected: BMI, total operating room time (TORT), surgical operating room time (SORT), ASA status, perioperative and postoperative complications, age, and gender.ResultsTwo hundreds and thirty-four patients were included and stratified into obese (BMI >30) and non-obese (BMI < 30) categories. Statistical analysis was performed comparing TORT against the obesity category along with other variables. Independent sample t-test demonstrated that obesity increases TORT and SORT by 16.8 min (P = 0.0002) and 9.3 min (P = 0.03), respectively, compared to the non-obese group. Multivariate linear regression analysis demonstrated no statistically significant impact of gender, or ASA status on total operating or surgical time. Obesity was associated with increased perioperative complications (odds ratio [OR], 6.21; 95% CI, 1.18–32.80; P = 0.03) and postoperative complications (OR, 3.97; 95% CI, 1.29–12.26; P = 0.02).ConclusionsObesity leads to longer TORT and SORT during primary cochlear implant surgery. Obesity is also associated with increased perioperative and postoperative complications compared to non-obese patients. These data have implications with utilization of operating room resources.     

Magnetic resonance imaging in patients with meningitis induced hearing loss

The aim of this multicentre study was to compare T1 with T2 weighted MRI scans of the labyrinth after meningitis and to investigate whether waiting with scanning improved the reliability of diagnosing an ongoing process such as cochlear osteogenesis. Forty-five patients were included who suffered from meningitis induced hearing loss (radiological imaging <1 year after meningitis). Twenty-one gadolinium enhanced T1 and 45 T2 weighted MRI scans were scored by two radiologists regarding the condition of the labyrinth. These radiological observations were compared with the condition of the cochlea as described during cochlear implantation. A higher percentage of agreement with surgery was found for T2 (both radiologists 73%) than for T1 weighted MRI scans (radiologist 1: 62%, radiologist 2: 67%), but this difference is not significant. There was no significant difference between early (0–3 months) and late (>3 months) scanning, showing that radiological imaging soon after meningitis allows early diagnosis without suffering from a lower agreement with surgical findings.     

Patients' involvement in choosing a cochlear implant

Abstract

Objective

The study describes the procedure followed by the South of England Cochlear Implant Centre, Southampton in involving the patients in their choice of device and it also describes the reasons given by patients for choosing a particular device.

Methods

A retrospective service evaluation of 43 adults and 19 children was carried out and the data was analysed.

Results

A wide range of reasons for choosing a particular device were reported. However, it is notable that the single most common reason for choosing a particular device was related to the aesthetics.

Discussion

The data suggest that the main reason for choosing a particular device related more to the aesthetics and comfort of the device irrespective of the technical aspects.     

Meningitis and a safe dexamethasone-eluting intracochlear electrode array

Abstract

Objectives

To evaluate the potential risk of pneumococcal meningitis associated with the use of a dexamethasone-eluting intracochlear electrode array as compared with a control array.

Methods

In two phases, adult Hooded–Wistar rats were implanted via the middle ear with an intracochlear array and were inoculated with Streptococcus pneumoniae 5 days post-surgery. Phase I created a dosing curve by implanting five groups (n = 6) with a control array, then inoculating 5 days later with different numbers of S. pneumoniae: 0 CFU, 10³ CFU, 10⁴ CFU, 10⁴ CFU repeated, or 10⁵ CFU (colony forming units). A target infection rate of 20% was aimed for and 10⁴ CFU was the closest to this target with 33% infection rate. In phase II, we implanted two groups (n = 10), one with a dexamethasone-eluting array, the other a control array, and both groups were inoculated with 10⁴ CFU of S. pneumoniae 5 days post-surgery.

Results

The dexamethasone-eluting array group had a 40% infection rate; the control array group had a 60% infection rate. This difference was not statistically significant with a P value of ≥0.5.

Conclusion

The use of a dexamethasone-eluting intracochlear electrode array did not increase the risk of meningitis in rats when inoculated with S. pneumoniae via the middle ear 5 days following implantation.     

A practical,single-view alternative to Stenver's for plain radiographic unilateral and bilateral post-cochlear implant position check

Abstract

Introduction: ‘Stenver's’ is the standard plain radiograph view to check the electrode position after cochlear implantation. However, a reproducible alignment for intra-individual comparison of electrode position using a true Stenver's alignment is not always straightforward to achieve, particularly for inexperienced radiographers, or on non-compliant children. In addition, two ionizing exposures in two different positions are required for bilateral cochlear implants.

Aims: To assess the efficacy of other, more simple, single-exposure radiographs for the assessment of electrode position.

Methods: Dummy electrodes and receiver units were bilaterally implanted into a cadaver. Plain radiographs in Stenver's views, and plain antero-posterior (AP) midline radiographic single views incorporating both implants were obtained with the tube at a range of angles tilted caudal and cranial to the perpendicular. Five internationally renowned cochlear implant surgeons were each asked if each radiograph gave adequate information for unilateral and for bilateral implants and they were asked to list in order of their favoured top three views.

Results: No surgeon thought that a single-exposure Stenver's view was adequate for assessment of the contra-lateral side. Consensus was that all AP views were fit for the purpose, with no preference given between each of the AP views. The ipsi-lateral Stenver's was considered to give better depth of insertion information.

Conclusion: There is no apparent advantage of caudal and cranial tilt angles over a straight perpendicular AP. A single-view AP radiograph is an alternative to Stenver's view for a post-unilateral and post-simultaneous bilateral cochlear implant check.