Biomedical subjects

Martin Kompis

Publications and source records attributed to Martin Kompis.

7 recordsLinked to original sources

PubMed2003

Scuba diving with cochlear implants.

We report on a patient with bilateral cochlear implants (a Med-El Combi40 and a Med-El Combi40+), as well as considerable experience in scuba diving with both of his implants. After having been exposed to 68 and 89 dives, respectively, in depths of up to 43 m, both cochlear implants are in working order and the patient continues to receive excellent speech recognition scores with both cochlear implant systems. The presented data show that scuba diving after cochlear implantation is possible over a considerable number of dives without any major negative impact on the implants.

Cochlear Implants↗

PubMed2003

Valuable use of computer-aided surgery in congenital bony aural atresia.

Congenital aural atresia repair is difficult owing to unpredictable anatomy. Benefits may be gained from computer-aided surgery (CAS), but its exact role has yet to be clearly defined. This is a retrospective study of 18 patients with bony type C (Schuknecht classification) congenital atresia. In the first group (n = 9), repair was performed with CAS while in the second group (n = 9), similar intervention was applied without CAS. Intra- and post-operative clinical and audiological findings were compared. CAS computed tomography (CT) images correlated well with intra-operative findings giving the surgeon more security and reducing operative time by 25 minutes. In our estimation, CAS is valuable for type C congenital aural atresia repair. It serves as an educational tool and as a guide for the experienced surgeon in critical situations where anatomical landmarks are distorted and where access is limited.

Abnormalities, Multiple↗

PubMed2002

Changes of voice and articulation in children with cochlear implants.

OBJECTIVE: The different speech sounds are formed by the primary voice signal and by the shape of the articulation tract. With this mechanism, specific overtones, the formants, are generated for each vowel. The objective of this study was to investigate the fundamental frequency (F0) of the voice signal and the first three formants (F1-F3) as a parameter of the articulation in prelingually deafened children at different timepoints after cochlear implantation (CI) compared with children with normal speech development. METHODS: Using the Kay CSL 4300B, the fundamental frequency and the formants F1-F3 of the Swiss-German vowel /a/ were investigated at different timepoints after CI in 20 prelingually deafened children aged 3.8-10.2 years by means of spectrographic and linear predictive coding (LPC) analysis. RESULTS: Children who had been operated before their fourth birthday showed no significant deviation in their fundamental frequency from age- and sex-matched peers, whereas a significant difference was documented in children who were older at the time of implantation. The first formant was very stable in every child and showed only discrete deviations from the normal range. The second and third formants, however, developed a broader scatter, but there was no systematic deviation of these formants to higher or lower values. The F1:F2 ratio was normal in children who were implanted at the age of up to 4 years and more centralized in children who were older at the time of implantation, as is known from the hearing impaired. CONCLUSIONS: Our results indicate that prelingually deaf children who receive a cochlear implant before their fourth birthday attain a better acoustic control over their speech, normalizing their fundamental frequencies and improving their articulatory skills.

Articulation Disorders↗

PubMed2002

Electromagnetic interference of bone-anchored hearing aids by cellular phones revisited.

The electromagnetic interference of the recently introduced bone-anchored hearing aid (BAHA) model "BAHA Compact" by digital cellular phones is investigated and compared with that of the older "BAHA Classic 300" model. Measurements with two different digital cellular phones in a laboratory setting indicated that the noise level due to electromagnetic interference was at least 10 dB lower for the BAHA Compact device than for the BAHA Classic 300. To compare the experience of patients using the BAHA Compact with those using a BAHA Classic 300 in an earlier study, a survey was performed. Six users of a BAHA Compact who used digital cellular phones participated in the survey. Four patients did not hear any noise associated with the use of a digital cellular phone. Two patients reported hearing quiet sounds when they were on the telephone, but not when somebody else in the vicinity used a digital cellular phone. These findings confirm that the susceptibility to electromagnetic interference of the BAHA Compact device is low.

Cell Phone↗

PubMed2002

Evaluation of a noise reduction system for the assessment of click-evoked otoacoustic emissions.

A recently proposed noise reduction system intended to facilitate the assessment of click-evoked otoacoustic emission (CEOAE) in noisy environments [Comput. Biol. Med. 30, 341 (2000)] is evaluated using 13 normally hearing ears and 9 ears with a sensorineural hearing loss. The noise reduction system is based on an adaptive noise canceller design using an additional noise-only reference microphone and intended to reduce externally generated noise. The system is tested in quiet and at different levels of white noise. The three main design parameters of the noise reduction system (adaptation time constant, length of the adaptive filter, and position of the noise reference microphone) are varied systematically in different experiments. With the noise reduction system active, CEOAE can be assessed correctly at noise levels which are 5 to 9 dB higher than without the noise reduction system. For the range of adaptation time constants considered (65.6 to 656 ms), no statistically significant effect on the amount of noise reduction is observed. Noise reduction is highest when the reference microphone is positioned close to the ear probe. Using this reference microphone position and adaptive filters of 6.56 ms in length, average noise reductions of 7.17 to 8.50 dB are achieved.

Acoustic Stimulation↗

PubMed2002

Intra- and intersubject comparison of cochlear implant systems using the Esprit and the Tempo+ behind-the-ear speech processor.

A patient with bilateral profound deafness was implanted with a Nucleus CI24M cochlear implant (CI) and used an Esprit behind-the-ear (BTE) speech processor. Thirteen months later, the implant had to be removed because of a cholesteatoma. As the same electrode could not be reinserted, a Medel combi40s CI was implanted in the same ear, and the patient used a Tempo+ BTE processor. After 1 year of use of the Combi40s/Tempo+ system, speech recognition was better and was rated better subjectively than with the CI24M/Esprit system. Speech recognition and subjective ratings were also assessed for two matched groups of nine CI users each, using either an Esprit or a Tempo+ processor. On average, speech recognition scores were higher for the group of Tempo+ users, but the difference was not statistically significant. Users of the Esprit processors rated their device higher in terms of cosmetic appearance and comfort of wearing.

Acoustic Stimulation↗

PubMedDate not supplied

Assessment of auditory skills in 140 cochlear implant children using the EARS protocol.

Auditory performance of cochlear implant (CI) children was assessed with the Listening Progress Profile (LiP) and the Monosyllabic-Trochee-Polysyllabic-Word Test (MTP) following the EARS protocol. Additionally, the 'initial drop' phenomenon, a recently reported decrease of auditory performance occurring immediately after first fitting, was investigated. Patients were 140 prelingually deafened children from various clinics and centers worldwide implanted with a MEDEL COMBI 40/40+. Analysis of LiP data showed a significant increase after 1 month of CI use compared to preoperative scores (p < 0.01). No initial decrease was observed with this test. Analysis of MTP data revealed a significant improvement of word recognition after 6 months (p < 0.01), with a significant temporary decrease after initial fitting (p < 0.01). With both tests, children's auditory skills improved up to 2 years. Amount of improvement was negatively correlated with age at implantation.

Adolescent↗