Cochlear implantation is a treatment for patients with severe sensorineural hearing loss/deafness, who get no help from ordinary hearing aids. The cochlear implant is surgically placed under the skin near the ear and a very thin electrode array is introduced into the cochlea of the inner ear, where it stimulates the remaining nerve fibers (1,2). The operation is complicated; it is performed with the aid of a microscope, and involves drilling very close to vital vessels and important nerves. The method was introduced in Sweden in 1984 by Professor Göran Bredberg, then at Stockholm Söder Hospital. High resolution computed tomography (CT) of the temporal bone is a part of the preoperative evaluation preceding cochlear implantation. It is a method for visualizing the bony structures of the middle and inner ear - to diagnose pathology and to describe the anatomy. In Stockholm, these examinations have usually been performed at the Radiology Department of Stockholm Söder Hospital. Examinations of cochlear implant candidates from other parts of Sweden and from abroad are also sent there for special reviewing. The first work concerns CT of the temporal bone and cochlear implant surgery in children with CHARGE association. This is a rare condition with multiple congenital abnormalities, sometimes lethal. Children with CHARGE have different combinations of disabilities, of which impairments of vision and hearing, as well as balance problems and facial palsy can lead to developmental delay. There have been few reports of radiological temporal bone changes and none of cochlear implant surgery for this group. The work includes a report of the findings on preoperative CT and at surgery, as well as post-implant results in two children. A review of the latest diagnostic criteria of CHARGE and the temporal bone changes found in international literature is also included. The conclusion was that certain combinations of temporal bone changes in CHARGE are, if not specific, at least extremely rare in other materials. CT can visualize these changes and be used as a diagnostic tool. This is important, since some of the associated disabilities are not so obvious from the start. Early treatment is vital for the child's development. This work also shows that cochlear implantation may help some of these often very isolated children to communicate. The second work is a radioanatomic study of one of the structures of the inner ear - the bony canal for the cochlear nerve. It involves measurements of the dimensions of the canal on 117 silicone rubber casts of the temporal bone (from a unique collection of casts at Uppsala temporal bone laboratory) and on 50 clinical CT-studies (100 ears). The purpose was to show the normal variation, which is of use in the appraisal of congenital temporal bone malformations on CT. Based on our results we propose that if the canal is less than 1.4 mm, as measured on CT, the possibility of cochlear nerve abnormality should be considered. This is of interest since aplasia of the cochlear nerve is a contraindication to cochlear implantation. If the canal is wider than 3.0 mm, then other anomalies may coexist, with the risk of CSF gusher when a cochleostomy or stapedectomy is performed.
There are currently no agreed-upon criteria to establish candidacy for bilateral cochlear implants (CIs). This study categorized practice patterns for establishing bilateral CI candidacy.
A postal survey was sent to all practices performing CIs in the United States and Canada. The survey queried centers regarding candidacy criteria for bilateral implantation, testing parameters, definition of 'best aided condition', use of testing in noise, localization, and quality-of-life questionnaires. The survey was resent to non-responding centers 4 weeks after the initial mailing.
The overall response rate was 40%. 'Best aided condition' (70%) and hearing in noise (52%) were used to establish bilateral candidacy, while 45% of centers offered bilateral implants to all candidates. The majority of respondents defined 'best aided' as hearing aids only (57% non-exclusive) or CI and hearing aid together (57%). Only 25% considered a CI alone as best aided. Nearly 5% considered no aiding to be the best aided. Sound localization was used by 8% of respondents for candidacy assessment. Reimbursement affected candidacy decision for 45%. There was variability in stimulus levels (60, 50, 45, and 55 dB), signal-to-noise ratios, and speaker orientations used.
There are no consistent criteria to assess patients for bilateral CIs. This practice variation makes comparing outcomes across centers challenging and leaves open the possibility of having external standards imposed by regulators or payors. Standardization of candidacy assessment is necessary to develop best practices for bilateral cochlear implantation both to optimize patient outcomes and to ensure the continuity of coverage for these services.
INTRODUCTION: Hearing loss affects 1.5 of newborns in Denmark. New research estimates that genetic factors account for 60% of hearing loss present at birth or in early childhood. The growing knowledge of the genetic causes of hearing loss provides new potential in the diagnostic process, either as prenatal diagnostics (PND) by means of placenta biopsy or amniocentesis or as a supplement to the existing audiologic screening. The purpose of this study was to shed light on the attitude towards PND among the parents of 22 children who received a cochlear implant in the cochlear implant centre of Western Denmark. MATERIALS AND METHODS: The parents received a questionnaire with questions on demographics and general attitudes and personal views regarding PND. RESULTS: In total, 42 persons received a questionnaire, 18 replied (41%). There was generally a positive attitude towards attaining early knowledge about the child's hearing status. The most significant reason for this attitude was that it would make it possible to prepare for having a deaf child. Only 6% thought that the obtained knowledge would lead to termination of pregnancy. CONCLUSION: In consistency with these parents' point of view, audiologic testing was implemented in Denmark in 2004. In future, screening for hearing loss would benefit from the addition of molecular genetic testing to detect late-onset hearing loss.
This study documents child, family and educational characteristics of a large representative sample of 8- to 9-yr-old prelingually deaf children who received a cochlear implant by 5 yr of age. Because pre-existing factors such as the child's gender, family characteristics, additional handicaps, age at onset of deafness and at implant, may affect postimplant outcomes, these variables must be accounted for before the impact of educational factors on performance with an implant can be adequately determined. Classroom variables that may affect postimplant outcomes include placement in public or private, mainstream or special education, oral or total communication environments. Other intervention variables include type and amount of individual therapy, experience of the therapist and parent participation in therapy. Documenting these characteristics for a large representative sample of implanted children can provide clinicians and researchers with insight regarding the types of families who sought early cochlear implantation for their children and the types of educational programs in which they placed their children after implantation. It is important to undertake studies that control for as many of these factors as possible so that the relative benefits of specific educational approaches for helping children to get the most benefit from their cochlear implant can be identified.
Over a 4-yr period, 181 children from across the US and Canada, accompanied by a parent, attended a cochlear implant research camp. Parents completed questionnaires in which they reported the child's medical and educational history, characteristics of the family, and their participation in the child's therapy. The parent listed names and addresses of clinicians who had provided individual speech/language therapy to the child and signed permission for these clinicians to complete questionnaires describing this therapy.
To the extent that this sample is representative of those families seeking a cochlear implant for their child, especially during the initial period of device availability, this population can be characterized as follows. Most parents had normal hearing, were of majority (white) ethnicity and had more education and higher incomes than the general population. The families tended to be intact with both a mother and a father who involved their hearing-impaired child in family activities on a regular basis. The children were enrolled in the full range of educational placements available across the United States and Canada. Fairly even distributions of children from public and private schools, special education and mainstream classes and oral and total communication methodologies were represented. Educational placement changed as children gained increased experience with a cochlear implant. They received an increased emphasis on speech and auditory skills in their classroom settings and tended to move from private school and special education settings to public school and mainstream programs. These data support the position that early cochlear implantation is a cost effective procedure that allows deaf children to participate in a normal school environment with hearing age mates.
In July 2002, a cluster of bacterial meningitis (BM) cases was identified among European cochlear implant recipients (CIRs), prompting Health Canada to conduct a retrospective cohort study to determine the rate of BM infection among Canadian CIRs and to identify risk factors for acquiring BM.
A survey was mailed to 1,432 Canadian CIRs who had received implants during January 1995-July 2002 to assess occurrence of postimplant BM infection. Data collection included demographics, episodes of meningitis, and vaccination status.
A total of 1,024 (72%) surveys were completed. Median age of CIRs at implantation was 16 years (range: 7 months-81 years). Five (0.5%) cases of BM infection were reported (two pneumococcal, one meningococcal, and two of unknown etiology); one CIR died. Four cases occurred among children aged or =18 years and 2.9 among those aged
To present the results of a survey administered to a group of early-deafened cochlear implants adults and to report the level of perceived benefit.
Large tertiary referral centre.
A 47-item questionnaire designed to evaluate cochlear implant use and benefit was sent to 42 early-deafened adult cochlear implant users. The questionnaire can be divided into seven subcategories: time of use, associated symptoms, communication, employment status and function, socialization, perceived benefit, and the impact on quality of life. Responses from 30 patients were received.
The majority of our patients use their cochlear implant all of their waking hours. The majority of patients continue to depend on lip-reading and hearing as their main mode of communication, although they reported improved lip-reading skills with their cochlear implant. Twenty-three patients (76.7%) were employed. Eleven patients had a change in employment subsequent to cochlear implantation, nine (81.8%) of whom attributed this to their cochlear implant. Our patients als reported greater independence, a greater sense of safety in their environment, and an improved social life. Twenty-nine patients (96.7%) said that they were satisfied with their implant, 28 (93.3%) said that they would go through the same process again, and 27 (90%) said that they would recommend it to a friend in a similar situation. Twenty-nine patients (96.7%) stated that the cochlear implant has had a positive effect on their quality of life. Family and peer support, prior auditory-verbal therapy, and a positive attitude were the most commonly cited factors in successful cochlear implant use.
Early-deafened adult cochlear implant users perceive significant benefit from cochlear implantation. Importantly, family and peer support, prior auditory-verbal therapy, and a positive attitude are considered important factors in maximizing this benefit.