Graeme Clark Collection

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    Speech perception in implanted children: influence of preoperative residual hearing on outcomes [Abstract]
    Cowan, R. S. C. ; Barker, E. J. ; Pegg, P. ; Dettman, S. ; Rennie, M. ; Galvin, K. ; Meskin, T. ; Rance, G. ; Cody, K. ; Sarant, J. ; Larratt, M. ; Latus, K. ; HOLLOW, RODNEY ; Rehn, C. ; Dowell, R. C. ; Pyman, B. ; Gibson, W. P. R. ; Clark, Graeme M. ( 1998)
    Since the first child was implanted with the Nucleus 22-channel prosthesis in Melbourne in 1985, several thousand children world-wide have now benefitted from this technology. More effective paediatric assessment and management procedures have now been developed, allowing cochlear implants to be offered to children under the age of 2 years. Improvements in speech processing strategy have also been implemented in the Nucleus implant system, resulting in increased mean speech perception benefits for implanted adults. Although a range of performance on formal measures of hearing, speech or language has been reported for children using implants, results from the first decade of implant experience consistently show that significant benefits are available to children receiving their implant at an early age. Reported speech perception results for implanted children show that a considerable proportion (60%) of paediatric patients in the Melbourne and Sydney clinics are able to understand some open-set speech using electrical stimulation alone. These results, and the upward trend of mean speech perception benefits shown for postlinguistically deafened adults have raised questions as to whether severely, or severely-to-profoundly deaf children currently using hearing aids would in fact benefit more from a cochlear implant. To investigate the potential influence of the degree of preoperative residual hearing on postoperative speech perception, results for all implanted children in the Melbourne and Sydney cochlear implant programs were analysed. Results showed that as a group, children with higher levels of preoperative residual hearing were consistently more likely to achieve open-set speech perception benefits. Potential factors in this finding could be higher levels of ganglion cell survival or greater patterning of the auditory pathways using conventional hearing aids prior to implantation. Conversely, children with the least preoperative residual hearing were less predictable, with some children achieving open-set perception, and others showing more limited closed-set benefits to perception. For these children, it is likely that preoperative residual hearing is of less significance than other factors in outcomes.
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    Results for children and adolescents using the multichannel cochlear prosthesis [Abstract]
    Dowell, Richard C. ; Clark, Graeme M. ; Dettman, Shani J. ; Dawson, Pamela W. ( 1992)
    The first adolescent to use the 22-electrode cochlear prosthesis was Implanted In Melbourne in 1985 and the first child (less than 10 years), the following year. Since then, over 100 children have received the cochlear prosthesis in Australia and over 1200 worldwide. Detailed assessment of 200 children in the U.S.A., Australia and Germany lead to the market approval of the prosthesis by the U.S. Food and Drug Administration in July 1990. The analysis of results for these children has proven to be difficult due to the use of different tests in different places, the lack of appropriate assessment tools for young children, the wide range of performance, and the problems of cooperation for young children. Despite these problems, some trends are beginning to emerge in the speech perception results for implanted children. Children with a greater amount of auditory experience before becoming profoundly deaf tend to perform better, as do children with more experience with the cochlear prosthesis. Those with a greater number of electrodes in use also perform better, a result supported by adult studies. Although older prelinguistically deafened children do not perform as well as postlinguistically deafened adults, there appears to be little difference between results for pre-and post-linguistically deafened young children. These trends In speech perception results will be discussed in more detail.
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    Speech perception results in children using the 22-electrode cochlear implant [Abstract]
    Dawson, P. W. ; Blamey, P. J. ; Rowland, L.C. ; Dettman, S. J. ; Altidis, P. M. ; Clark, Graeme M. ; Busby, P. A. ; Brown, A. M. ; Dowell, R. C. ; Rickards, F. W. ( 1990)
    Twenty-one profoundly hearing impaired children ranging in age from 3 to 20 years have been implanted with the 22-electrode cochlear implant (Cochlear Pty ltd) at the University of Melbourne Cochlear Implant Clinic. Five children (aged 6.0 to 14.8 years) have achieved substantial scores on open set speech tests using hearing without lipreading. Phoneme scores in monosyllabic words ranged from 30% to 72%. Word scores in sentences ranged from 26% to 74%. Four of these five children were implanted during preadolescence and the fifth who had a progressive loss, was implanted during adolescence. Eight children (aged 3.0 to 11 years), have either been implanted recently or are too young for detailed assessments. However some have shown using closed set speech perception tests or vowel imitation tasks, that they are beginning to use the auditory input provided by the implant. The remaining children (aged 13.11 to 20.1 years) have not demonstrated open set recognition but are all full time users of the device. This group was implanted during adolescence after a long duration of profound deafness. The results will be discussed with reference to a number of variables which may contribute to successful implant use; such as age of onset of deafness, duration of deafness. age of implantation, educational program and type of training.
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    Results in children using the 22 electrode cochlear implant [Abstract]
    Dawson, Pam W. ; Blamey, Peter J. ; Clark, Graeme M. ; Busby, P. A. ; Rowland, L.C. ; Dettman, S. J. ; Brown, A. M. ; Dowell, Richard C. ; Rickards, Field W. ; Alcantara, Joseph I. ( 1989)
    Abstract not available due to copyright.