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.

The limitations of coronary angiography: identification of a critical coronary stenosis using intravascular ultrasound.

Coronary angiography is considered the gold standard method of imaging coronary stenoses. Quantitative coronary angiography (QCA) has helped to provide information about the degree of stenosis which is used as a surrogate to indicate impaired flow in a coronary bed. QCA however can underestimate disease severity. In this case intravascular ultrasound identifies a critical coronary stenosis not seen on angiography.

Cochlear implantation for progressive hearing loss.

The concept of neural plasticity and the early natural abilities of hearing children to acquire speech and language without instruction have led many authorities to advocate cochlear implantation before the age of 5 years in congenital deafness. Older children therefore become lower priority for scarce public funds because they are perceived to have passed the "window of opportunity" to learn speech, even if hearing is restored, and continue to rely on sign language. This paper shows that a subgroup of congenitally deaf children exists, who, having made good progress with conventional hearing aids, suffer a sudden or progressive hearing deterioration which arrests the speech development. Sixty children have been implanted in the Cambridge Programme, half for meningitis or other acquired losses and half for congenital prelingual deafness. Six of this latter group were congenital but progressive; their progress, deterioration, and improvement after implantation are summarised.

Paediatric cochlear implantation--the balance between professional caution and urgency of treatment.

There is a constant pressure to reduce the age of cochlear implantation in profoundly deaf children and thereby improve the auditory verbal language development in implantees. We effected a change in the regimen for the assessment of new referrals, and show how this has shortened the time taken in Cambridge to complete assessment and offer implantation in appropriate cases. We achieved a reduction in the duration of assessment of 2.8 months (which was not, however, statistically significant) by simple reorganization, while, we believe, maintaining the standards of assessment.

Surgical removal of 11 cochlear implants--lessons from the 11-year-old Cambridge programme.

This is a retrospective study of 10 patients (11 ears) out of 132 cochlear implant patients of the Cambridge cochlear implant programme. These patients have all been explanted. Individual problems have been studied, relevant literature reviewed and the pitfalls of implant surgery re-examined in the light of our experience.

Patient performance over eighteen months with the Ineraid intracochlear implant.

We present our results with an 18-month follow-up for 15 adult patients treated with the Ineraid (formerly Symbion) four-channel intracochlear implant. All were postlingually deaf with profound or total hearing loss. Performance was tested in lipreading, implant only, and combined lipreading and implant modes using Boothroyd word lists, Bamford-Kowal-Bench (BKB) sentences, and Connected Discourse Tracking. Assessments were made after 10 hours of training and again at 9 and 18 months postimplantation. Mean scores at 18 months in the implant only mode were for Boothroyd word lists 39%, for BKB sentences 47%, and for connected discourse tracking 31 words per minute. In the combined implant and lipreading mode the mean scores were for Boothroyd word lists 85%, for BKB sentences 96%, and for connected discourse tracking 75 words per minute. A profile of implant performance against time shows that after 10 hours' training, 12 of the 15 subjects had some speech discrimination in the implant only mode for all three tests. When using their implant combined with lipreading, all 15 subjects improved their speech discrimination scores over those obtained with lipreading alone after 10 hours' training. By 9 months, all subjects had some speech discrimination in the implant only mode on all three tests. Between 9 and 18 months there was a slight trend toward improvement in implant performance, both when the implant was used alone and when it was combined with lipreading.

Cochlear implant results: a comparison of live-voice and videotaped tests.

The Cambridge Cochlear Implant Programme has so far implanted the Ineraid multichannel cochlear implant in 16 profoundly deaf adult patients; there has been a 9-month or longer follow-up period with these patients. We have evaluated these patients by open-set Bamford-Kowal-Bench (BKB) Standard Sentence List testing in two different delivery strategies, live-speaker testing by the same speaker and high-resolution videotaped testing. The performance in lip reading both before and 9 months after implantation has been tested, as well as performance with the implant alone and with the implant in conjunction with lip reading at the 9-month stage. We have compared the performance in these two delivery strategies and have found a significantly better performance in the live-speaker tests that is attributable to slower and perhaps more sympathetic delivery. We have also found evidence of a ceiling effect in the performance of the implant with lip reading in the live-speaker mode and, of greater importance, a floor effect in the performance of the implant alone with the videotaped test. These results and the implications for a complementary role of these two test-delivery modes are discussed.

Maintaining the Ineraid cochlear implant.

Managing a patient with acquired profound deafness with a cochlear implant involves a lifetime commitment to rehabilitation and also to maintaining the device in a functioning condition. This paper describes the Cambridge experience of maintaining the Ineraid cochlear implant in a series of 25 patients over a 4 year period. On average, maintenance (repair of replacement) of components was required every 2.3 months of implant use, although some minor variations were noted between patients, and between component type. This rate of failure is sufficient to cause an Implant Centre to consider provision for repairs and holding of spare stock. It should be remembered that each breakdown returns the patient to a deafened state, albeit temporarily, but this can cause significant distress.

Profound deafness treated by the Ineraid multichannel intracochlear implant.

Twelve deaf adults and two deaf children were treated with the Ineraid (formerly Symbion) four channel intracochlear implant between September 1989 and October 1991 at Addenbrooke's Hospital in Cambridge. All were post-lingually totally deaf and had found themselves beyond the reach of hearing aids. The effect of the implant upon the patients ability to lip-read was tested with the speech tracking test, BKB sentences (comparable to CID sentences) and Boothroyd word lists (comparable to NU6 word lists). All patients showed an improvement in their ability to understand speech with the help of the implant. Discrimination of speech without lip-reading was tested with Boothroyd word lists and BKB sentences, eight patients (57 per cent) demonstrated some 'open set' speech discrimination. The acceptability of the carbon percutaneous pedestal is discussed from the patient's, audiologist's and surgeon's points of view.