Thomas P. Nikolopoulos

Age at Implantation: Its Importance in Pediatric Cochlear Implantation

Objective: To assess the influence of age at implantation on speech perception and speech intelligibility following pediatric cochlear implantation.

Categories of Auditory Performance: Inter-User Reliability

Categories of Auditory Performance (CAP) describes a scale used to rate outcomes from paediatric cochlear implantation in everyday life. It differs from more technical measures by being readily applied and easily understood by non-specialist professionals and by parents. Being based on subjective assessments, there is a need to establish whether ratings by different persons are comparable. Therefore, an analysis of inter-user reliability was undertaken using ratings from 23 children followed up at various intervals after implantation. Analysis relating scores by local teachers of the deaf and the teachers of the deaf at the implant centre revealed very high inter-user reliability (correlation coefficient 0.97). This result establishes the reliability of CAP as an outcome measure for use in cochlear implant programmes.

The development of auditory perception in children following cochlear implantation

The time course for the development of auditory perception in prelingually deaf children following cochlear implantation may extend over many years, thus making long-term studies necessary to evaluate any such outcome. However, few such studies exist in the literature. We prospectively followed-up a consecutive group of 133 prelingually deaf children up to 6 years following implantation. All children were prelingually deaf with age at onset of deafness < 3 years and age at implantation < 8 years. The aetiology of deafness was meningitis for 45 children (34%), congenital deafness for 77 children (58%) and other causes for 11 children (8%). All were implanted with a Nucleus-22 multi-channel cochlear implant and followed the same rehabilitation programme. No child was lost to follow-up and there were no exclusions from the study. Prelingually deaf children showed significant improvement in the auditory perception with implant experience. 82% of children who reached the 6-year interval could understand conversation without lip-reading. The respective percentage in the 4-year interval was 70%. The long-term results of cochlear implantation reveal that the majority of prelingually deaf children, when implanted before the age of 8 years, will develop significant auditory perception.

Approach to communication, speech perception and intelligibility after paediatric cochlear implantation.

Abstract The aim of this study was to explore the relationship between approach to communication, speech perception and speech intelligibility after cochlear implantation of young children with profound early deafness. A prospective speech perception and speech intelligibility assessment was undertaken on a consecutive group of implanted children. There were 46 children at the three-year, 26 at the four-year and 20 at the five-year intervals. All had been born deaf or deafened before the age of three and received cochlear implants before the age of seven. Their speech perception ability and the intelligibility of their speech were measured before cochlear implantation and annually thereafter. The childrens communication had been classified by their teachers of the deaf at each interval into one of two categories: those using an oral approach and those using a signing approach. Results revealed that at all intervals, those children classified as using oral communication significantly exceeded those using signed communication on measures of speech perception and intelligibility (p<0.05). When those children who had changed from signed to oral communication were compared at the three-year interval with those who used oral communication throughout, there was no significant difference in their results. However, it remains to be explored whether children use oral communication after cochlear implantation because they are doing well, or whether they do well because they are using oral communication.

Is there a correlation between vascular loops and unilateral auditory symptoms

Objectives: To assess whether contact of a vascular loop formed by the anterior inferior cerebellar artery (AICA) with the eighth cranial nerve correlated with unilateral auditory symptoms so as to produce a “vascular compression syndrome.” Study Design: Prospective evaluation of patients with unilateral auditory symptoms using magnetic resonance imaging (MRI) scans to identify contact of a vascular loop with the eighth cranial nerve. Methods: One hundred twelve patients with idiopathic unilateral auditory symptoms (42 women and 70 men, mean age of 51 years) were evaluated with MRI. Location of the vascular loop and contact with the eighth cranial nerve were assessed in each case. The asymptomatic contralateral ears of the patients were used as controls. A power analysis had determined the size of the sample to be studied. Results: The arterial loop was found to be in contact with the eighth cranial nerve in 28 (25%) of the 112 symptomatic ears and in 24 (21.4%) of the asymptomatic (control) ears. The statistical analysis revealed that the difference was not statistically significant. Conclusion: The results suggest that radiologic demonstration of contact between a vascular loop formed by the AICA and the eighth cranial nerve on MRI scans should be considered a normal anatomic finding and should not, on its own, be used to support the diagnosis of a “vascular compression syndrome.” Laryngoscope, 108:1739–1742, 1998

Cochlear implantation in children with large vestibular aqueduct syndrome and a review of the syndrome.

OBJECTIVE Children with Large Vestibular Aqueduct Syndrome (LVAS) frequently develop speech and language skills prior to deterioration of their hearing. Operations designed to halt the progression of hearing loss have largely failed so the question of Cochlear Implantation in these children has arisen. It had been suggested that there would be technical difficulties in implanting these patients and, therefore, there had been an initial reluctance to proceed to implantation. The aim of the present paper is to assess surgical and functional outcomes in implanted children with LVAS and review the related literature. MATERIAL AND METHODS From the 170 children assessed by MRI in the Nottingham Paediatric Cochlear Implant Programme, seven (4%) were identified as having LVAS. Four of these children were implanted and had at least 12 months follow up. Two of the children are on the waiting list for implantation and one child was not implanted because of absence of the cochlear nerve. Operative findings, complications and outcome measures were recorded. The auditory skills of the children were assessed before implantation and 1 year following implantation. A literature search was done to identify other series with experience in implanting children with LVAS. RESULTS Full insertion of the electrode array was achieved in all our cases. After cochleostomy two patients experienced a mild CSF leak that was easily controlled by the muscle graft. On the first day post-operation two patients were nauseous and one had an episode of vomiting, however, all were discharged within 24 h of surgery. Initial outcome measures at 12 months post-implantation were encouraging showing significant progress in childrens auditory skills. CONCLUSIONS The results of the present study and the review of the literature suggest that LVAS is not a contraindication to implantation as initial concerns about severe perilymph leaks and surgical complications have proved to be unfounded. The post-operative progress of these children in listening skills also suggest that these children are suitable for cochlear implantation

Educational placement of deaf children following cochlear implantation.

This study examined the educational placements, before cochlear implantation, of 121 deaf children, and the educational placements, two years after implantation, of the 48 children who had reached that stage, looking at the influence of age at implantation and duration of deafness on the placement of these children. In addition, it compared the educational placements of those given implants prior to schooling, and those given implants when already in an educational setting. Categories used were pre-school, school for the deaf, unit or resource base within a mainstream school and full-time mainstream provision. Age at implantation and duration of deafness were found to be significant predictors of placement two years after implantation. The duration of deafness of children in schools for the deaf or units was twice that of children in mainstream education. Fifty-three per cent of children who were in pre-school at the time of implantation were in mainstream schools two years after implantation, whereas only 6% of those who were already in educational placements at the time of implantation were in mainstream education. This difference was statistically significant. The results indicate that children who are given implants early, before an educational decision has been made, are more likely to go to mainstream schools than those given implants when already in an educational setting.