A. M. Brown

Factors predicting postoperative sentence scores in postlinguistically deaf adult cochlear implant patients

A sample of 64 postlinguistically profoundly to totally deaf adult cochlear implant patients were tested without lipreading by means of the Central Institute for the Deaf (CID) sentence test 3 months postoperatively. Preoperative promontory stimulation results (thresholds, gap detection, and frequency discrimination), age, duration of profound deafness, cause of deafness, lipreading ability, postoperative intracochlear thresholds and dynamic ranges for electrical stimulation, depth of insertion of the electrode array into the scala tympani, and number of electrodes in use were considered as possible factors that might be related to the postoperative sentence scores. A multiple regression analysis with stepwise inclusion of independent variables indicated that good gap detection and frequency discrimination during preoperative promontory testing, larger numbers of electrodes in use, and greater dynamic ranges for intracochlear electrical stimulation were associated with better CID scores. The CID scores tended to decrease with longer periods of profound deafness.

Telephone use by a multi-channel cochlear implant patient. An evaluation using open-set CID sentences.

A totally deaf person with a multiple-channel cochlear prosthesis obtained open-set speech discrimination using the telephone. CID Everyday Sentences were presented by telephone to the patient, who repeated an average of 21 per cent of key words correctly on the first presentation, and 47 per cent when a repeat of the sentences was permitted. This result is consistent with the patients reports of telephone usage.

Speech processing studies using an acoustic model of a multiple‐channel cochlear implant

The speech perception of two multiple-channel cochlear implant patients was compared with that of three normally hearing listeners using an acoustic model of the implant for 22 different speech tests. The tests used included a minimal auditory capabilities battery, both closed-set and open-set word and sentence tests, speech tracking and a 12-consonant confusion study using nonsense syllables. The acoustic model represented electrical current pulses by bursts of noise and the effects of different electrodes were represented by using bandpass filters with different center frequencies. All subjects used a speech processor that coded the fundamental voicing frequency of speech as a pulse rate and the second formant frequency of speech as the electrode position in the cochlea, or the center frequency of the bandpass filter. Very good agreement was found for the two groups of subjects, indicating that the acoustic model is a useful tool for the development and evaluation of alternative cochlear implant speech processing strategies.

Perception of Connected Speech Without Lipreading, Using a Multi-channel Hearing Prosthesis

Four of 13 totally deaf patients implanted with the Nucleus multi-channel hearing prosthesis at the University of Melbourne have demonstrated the ability to understand connected speech without lipreading or other visual cues. These patients were able to repeat verbatim unknown material read by a tester at rates of up to 35 words per minute. They were also able to understand an average of 78% of key words in everyday sentences in ideal acoustic conditions and 51% of equivalent material over the telephone. These results show that with a good proportion of postlingually deaf patients, the multi-channel hearing prosthesis can not only act as an aid to lipreading, but also restore effective speech understanding without lipreading.

Results in children using the 22‐electrode cochlear implant

This is an abstract of a paper presented at the 9th National Conference of the Audiological Society of Australia , Thredbo, NSW , 26- 29 April 1990.The Cochlear Implant Clinic, The Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne, Victoria 3052, Australia Five children (aged 6.0 to 14.8 years) out of a group of nine implanted with the 22‐electrode cochlear implant (Cochlear Pty. Ltd.) have achieved substantial open‐set speech recognition scores for monosyllabic word (30% to 72% for phonemes) and sentence (26% to 74% for words in sentences) tests using hearing without lipreading. Four of these five children were implanted during preadolescence and the fifth, who had a progressive loss, was implanted during adolescence. The remaining children who did not demonstrate open‐set recognition were implanted during adolescence after a long duration of profound deafness. Post‐operative performance on closed‐set speech perception tests was better than preoperative performance for the group of five children with open‐set recognition. Improvements in speech and language assessments were also noted for these children. The results are discus...

Clinical results with a hearing aid and a single-channel vibrotactile device for profoundly deaf adults

The speech perception of a group of 19 adults with post-lingual profound to total hearing loss was tested with nine closed-set speech tests without lipreading, two open-set tests without lipreading and two open-set speech tests with lipreading. The subjects were all prospective cochlear implant patients participating in a clinical trial of the implant and the results reported here were obtained as part of the pre-operative assessment. They were divided into groups on the basis of their prior experience with the aid(s), their speech detection thresholds with the two aids and their personal preferences. Seven of the subjects used a hand-held single-channel vibrotactile device and the other 12 used a powerful conventional hearing aid. Subjects from each group scored significantly better than chance on the closed set tests without lipreading. Training or regular hearing aid use was correlated with good performance on the closed-set tests. No subject showed a significant improvement of the lipreading score when the aid was used as a supplement. The use of sophisticated wearable tactile devices and extensive training may allow a better result, but in this clinical program, neither a hearing aid nor a single-channel vibrotactile device greatly benefited the postlingually profoundly deaf adults.

Governing the quality and safety of healthcare: A conceptual framework

Recent research has advanced understanding of corporate governance of healthcare quality, highlighting the need for future empirical work to develop beyond a focus on board composition to a more detailed exploration of the internal workings of governance that influence board engagement and activities. This paper proposes a conceptual framework to guide empirical research examining the work of board and senior management in governing healthcare quality. To generate this framework, existing conceptual approaches and key constructs influencing effectiveness are identified in the governance literature. Commonalities between governance and team effectiveness literature are mapped and suggest a number of key constructs in the team effectiveness literature are applicable to, but not yet fully explored, within the governance literature. From these we develop a healthcare governance conceptual framework encompassing both literatures, that outlines input and mediating factors influencing governance. The mapping process highlights gaps in research related to board dynamics and external influences that require further investigation. Organizing the multiple complex factors that influence governance of healthcare quality in a conceptual framework brings a new perspective to structuring theory-led research and informing future policy initiatives.