Hearing optimisation in neurofibromatosis type 2: A systematic review.

BACKGROUND: It is common for patients with neurofibromatosis type 2 to develop bilateral profound hearing loss hearing loss, and this is one of the main determinants of quality of life in this patient group. OBJECTIVES: The aim of this systematic review was to review the current literature regarding hearing outcomes of treatments for vestibular schwannomas in neurofibromatosis type 2 including conservative and medical management, radiotherapy, hearing preservation surgery and auditory implantation in order to determine the most effective way of preserving or rehabilitating hearing. SEARCH STRATEGY: A MESH search in PubMed using search terms (('Neurofibromatosis 2' [Mesh]) AND 'Neuroma, Acoustic'[Mesh]) AND 'Hearing Loss' [Mesh] was performed. A search using keywords was also performed. Studies with adequate hearing outcome data were included. With the exception of the cochlear implant studies (cohort size was very small), case studies were excluded. EVALUATION METHOD: The GRADE system was used to assess quality of publication. Formal statistical analysis of data was not performed because of very heterogenous data reporting. RESULTS: Conservative management offers the best chance of hearing preservation in stable tumours. The use of bevacizumab probably improves the likelihood of hearing preservation in growing tumours in the short term and is probably more effective than hearing preservation surgery and radiotherapy in preserving hearing. Of the hearing preservation interventions, hearing preservation surgery probably offers better hearing preservation rates than radiotherapy for small tumours but recurrence rates for hearing preservation surgery were high. For patients with profound hearing loss, cochlear implantation provides significantly better auditory outcomes than auditory brainstem implantation. Patients with untreated stable tumours are likely to achieve the best outcomes from cochlear implantation. Those who have had their tumours treated with surgery or radiotherapy do not gain as much benefit from cochlear implantation than those with untreated tumours. CONCLUSIONS: This review summarises the current literature related to hearing preservation/rehabilitation in patients with NF2. Whilst it provides indicative data, the quality of the data was low and should be interpreted with care. It is also important to consider that the management of vestibular schwannomas in NF2 is complex and decision-making is determined by many factors, not just the need to preserve hearing.

Predictors of audiological outcome following cochlear implantation in adults.

The objective of this study was to examine variables that may predict open set speech discrimination following cochlear implantation. It consisted of a retrospective case review conducted in a tertiary referral centre with a cochlear implant programme. The patients were 117 postlingually deafened adult cochlear implant recipients. The main outcome measures were Bench, Kowal, Bamford (BKB) sentence scores recorded nine months following implant activation. The variables studied were age at the time of surgery, sex, duration of hearing loss, aetiology of hearing loss, residual hearing, implant type, speech processor strategy, number of active electrodes inserted. Variables found to have a significant effect on BKB following univariate analysis were entered into a multivariate analysis to determine independent predictors. Multivariate ordinal regression analysis gave an odds ration of 1.09 for each additional year of deafness prior to implantation (confidence interval 1.06-1.13; p < 0.001). Duration of deafness prior to implantation is an independent predictor of implant outcome. It accounted for 9% of the variability. Other factors must influence implant performance.

Self-reported benefits from successive bilateral cochlear implantation in post-lingually deafened adults: randomised controlled trial.

Adult users of unilateral Nucleus CI24 cochlear implants with the SPEAK processing strategy were randomised either to receive a second identical implant in the contralateral ear immediately, or to wait 12 months while they acted as controls for late-emerging benefits of the first implant. Twenty four subjects, twelve from each group, completed the study. Receipt of a second implant led to improvements in self-reported abilities in spatial hearing, quality of hearing, and hearing for speech, but to generally non-significant changes in measures of quality of life. Multivariate analyses showed that positive changes in quality of life were associated with improvements in hearing, but were offset by negative changes associated with worsening tinnitus. Even in a best-case scenario, in which no worsening of tinnitus was assumed to occur, the gain in quality of life was too small to achieve an acceptable cost-effectiveness ratio. The most promising strategies for improving the cost-effectiveness of bilateral implantation are to increase effectiveness through enhanced signal processing in binaural processors, and to reduce the cost of implant hardware.

Cochlear implant outcomes and quality of life in the elderly: Manchester experience over 13 years.

OBJECTIVES: To objectively evaluate the clinical and functional outcomes of cochlear implantation in an elderly population. DESIGN: Retrospective comparative study. SETTING: Neurotology unit at Manchester Royal Infirmary, a supraregional tertiary referral centre in collaboration with Adult Cochlear Implant Programme at The University of Manchester. PARTICIPANTS: All cochlear implant procedures (38) undertaken on post-lingually deafened elderly patients (age range at the time of implantation 65-80 years, n = 34) in the period from 1989 to 2002. MAIN OUTCOME MEASURES: Medical and surgical outcomes. Audiological performance outcomes for isolated words, words in sentences in quiet and noise. Functional outcome measures used are self-reported measures of the social, psychological and emotional aspects of quality of life, and the differences between expectations for functional outcomes and the realization of functional outcomes. They included expectation profiles, Glasgow Benefit inventory (GBI) and Glasgow Health Status Inventory Questionnaire (GHSI). RESULTS: There was statistically significant improvement post-implantation of both open and closed set test scores (P < 0.01). Eighty-two percentage of patients were completely satisfied with their cochlear implants. Patients judged that implantation restored half the loss of quality of life that they had experienced as a result of severe-profound deafness with a highly significant (P < 0.001) improvement in overall quality of life after implantation. The commonest post-operative observation was transient mild pyrexia. CONCLUSIONS: The age of a cochlear implant candidate should not be a factor in the candidacy decision-making process. The quality of life of our elderly recipients was significantly improved after cochlear implant.

Device nonuse among adult cochlear implant recipients.

OBJECTIVE: To examine the causes and prevalence of previous and current device nonuse among adults who have received cochlear implants. STUDY DESIGN: Retrospective case review. SETTING: Adult tertiary referral center for cochlear implantation. METHODS: Two hundred fourteen consecutively implanted adult patients. The length of implant use ranged from 1 month to 14 years. MAIN OUTCOME MEASURE: A period of 4 consecutive weeks of nonuse of cochlear implant, including both obligatory and elective nonuse. RESULTS: Twenty-nine adults (13.6% of implantees) were identified as having at some stage not used their device for a period of more than 4 consecutive weeks. The main reason was device failure (n = 11). Ten adults are current nonusers (4.7% of implantees). Reasons include surgical complication necessitating explantation (n = 3), comorbid illness (n = 3), elective nonuse (n = 2), audiologic complication (n = 1), and device failure (n = 1). CONCLUSION: The overall prevalence of device nonuse was noted to increase slowly with time. The role of psychologic factors in contributing to the decision of an individual to elect to opt out of device use remains unproven.

Trends and outcomes in the Manchester adult cochlear implant series.

The adult cochlear implant programme in Manchester was established in 1988, initially using funding obtained from the HEAR (Help Ear and Allied Research: charity number: 519784) charity before government resources became available in the mid-1990s. Manchester was the first centre in the UK to implant multichannel devices on a regular basis. To date, over 250 adults have been implanted, including nine bilateral and eight deaf-blind patients. All the patients have a postlingual onset of severe-profound hearing loss; 73% (n = 175) of the implants performed used a Nucleus multichannel implant and 24% (n = 58) used a Medel multichannel implant. In addition, the team has implanted three Medel single channel devices, two Ineraid devices and one Clarion High Focus II device. This study is a retrospective analysis of the trends and outcomes in implant fitting during the first 14 years (1988-2002) of the programme. The paper describes the patient demographics and audiological complications for 240 implantations performed on 214 patients. Speech perception outcomes are reported for a subset of the patients. The average score for the Bench, Kowal, Bamford sentence test at the post-18-month stage of implant use is 66% and for Arthur Boothroyd words 53%. Trends in the series are analysed with respect to the change in criteria for adult implantation, the move towards bilateral implantation and the rate of uptake of cochlear implants by different ethnic groups.

Non-auditory stimulation in adult cochlear implant users.

This is a retrospective case review of all 163 adults to have received multichannel cochlear implants on the Manchester University/Manchester Royal Infirmary programme between 1988 and 1998. The aims were to investigate the incidence of unwanted non-auditory effects of electrical stimulation (NAS) of the cochlea, and to try to identify any factors that seemed to be related to these effects. The effectiveness of programming strategies in eliminating unwanted effects was also studied. Most of the devices were Nucleus CI 22M or CI 24M. The remainder were Med-el Combi 40 or Combi 40+. NAS occurred in 23.9% of implantees. There were 20 cases of facial nerve stimulation (12.3%), 18 cases of pain in the ear or throat (11.0%) and one case of vestibulospinal spinal stimulation (0.6%). Two aetiologies were significantly associated with NAS. Otosclerosis tended to be associated with facial nerve stimulation and skull base fracture was associated with pain. Pain was associated with electrodes stimulated in the base turn of the cochlea and facial nerve stimulation tended to occur with more distally situated electrodes, close to labyrinthine segment of the nerve. There was no association with one particular make of device. The T and C levels for the rogue electrodes were in the normal range. It is concluded that the unwanted effects result from shorting of current through areas of low electrical resistance in the temporal bone. A number of different strategies were employed to prevent the effect, including alteration of current levels, removal of electrodes from the map and changing the stimulation mode, and this was successfully achieved in all cases. There was no difference between the performance of patients who had had NAS and those who had not, as assessed on open-set BKB sentence scores.

Cochlear implantation in the presence of chronic suppurative otitis media.

Nine patients are presented who underwent cochlear implantation in the presence of chronic suppurative otitis media. Four had a simple tympanic membrane perforation, four had a pre-existing mastoid cavity and one had cholesteatoma in the ear chosen for implantation. Patients with a simple perforation had a staged procedure with myringoplasty followed by cochlear implantation after an interval of three months. Patients with cholesteatoma or with an unstable mastoid cavity were also staged. A mastoidectomy or revision mastoidectomy was performed with obliteration of the middle ear and mastoid using a superiorly pedicled temporalis muscle flap and blind sac closure of the external meatal skin. After a further six months a second stage procedure was performed to confirm that the middle-ear cleft was healthy and to insert the implant. Patients presenting with a stable mastoid cavity underwent obliteration of the cavity and implantation of the electrode as a one-staged procedure. To date there have been no serious problems such as graft breakdown, recurrence of disease or implant extrusion, and all patients are performing well.

Cochlear implantation in otosclerosis: a unique positioning and programming problem.

A case is reported in which a Nucleus 22 channel cochlear implant was inserted into the basal turn of the cochlea of a patient with advanced otosclerosis. It then passed out of the anterior end of the basal turn into an otospongiotic cavity related to the cochlea. Seven electrodes were located in the basal turn and it was possible to map them sufficiently well for the patient to derive considerable benefit from the implant. The problem of implant induced facial nerve stimulation in otospongiosis is also discussed.

An audit of the cochlear implant service in Manchester.

The adult cochlear implant programme in Manchester was established in 1988 and the evaluation of the cochlear implant service involved the first 58 implants users (mean age = 51.65 years, range 19-75 years). Questionnaires were sent to implant users and their partners to evaluate the service with regard to provision of information, clinical care during in-patient assessments, waiting times, operation for cochlear implant and post-operative rehabilitation. The results show that the majority of patients (78 per cent) felt that the implant gave them as much or more benefit than expected. Areas identified for improvements include provision of more written information about cochlear implants; reduction in waiting times for first appointments; more information about the surgical risks and more instruction about home auditory training exercises for family and friends. As a consequence of the audit results the clinical practice and service provision for cochlear implantation in Manchester has been modified.

Explantation of a nucleus multichannel cochlear implant and re-implantation into the contralateral ear. A case report of a new strategy.

We present a unique case in which a multichannel cochlear implant device was explanted and the same device was re-implanted into the contralateral ear. A patient with bilateral total deafness secondary to head injury received an implant in his left ear but developed severe facial nerve stimulation. Because this stimulation could not be eliminated effectively with change of programming, it was decided to implant the contralateral ear. Since the device itself was functioning well, it was explanted from the left ear and re-implanted successfully into the right ear. Facial nerve stimulation was minimal in this ear and the patient demonstrated very good speech discrimination. To our knowledge, this is the first description of this strategy.