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C Fugain

Publications and source records attributed to C Fugain.

At least 19 recordsLinked to original sources
PubMed1995

Clinical results for the DIGISONIC multichannel cochlear implant.

The DIGISONIC is a digitized 15-channel cochlear implant. A special version of this implant has been designed for use in the totally obstructed cochlea. This device has 10 separate electrodes that may be inserted, one by one, into 10 different holes drilled in the bony cochlea. The device's 128-point Fast Fourier Transform analysis supplies the patient with the entire set of the sound information between 100 and 7800 Hz. The stimulation rhythm is set at a programmable frequency among 125 and 400 Hz or slaved to the fundamental pitch frequency. The flexibility of the microprocessor makes it possible to select the best width and mean value of each frequency band for each electrode. Many speech-coding strategies may be easily programmed as a function of scientific desiderata. The authors present clinical results for the first 28 patients they treated with this cochlear implant.

Adolescent↗
PubMed1995

Speech coding strategies of the digisonic fully digitized cochlear implant.

The Digisonic is a fully digitized cochlear implant. Because of its articulated array, its 15 electrodes can be inserted in the cochlea. Each electrode is recessed in a special silastic compartment of the array and has a very large stimulation area thanks to its large microrelief surface area. The small volume of its implanted receiver (flat cylinder diam 29 mm, 6.9 mm thick) allows it to be placed in 2-year-old children. The 128 point FFT of this device supply the patient with a full set of sound information between 64 and 7800 Hz. Electrode stimulation mode is sequential and stimulation rhythm is programmable. Electric crosstalk is decreased by the shape of the electrode array, and optionally by special programming of the neighboring electrodes. The speech therapist may select the width and peak value of each frequency band handled by each functional electrode. Because the versatility of this digitized emitter, many speech coding strategies can be easily programmed as a function of electrode responses or particular scientific considerations. A special version of this device, consisting of 10 separate electrodes, has been designed for use in patients with total obstruction of the cochlea. These insulated wires may be inserted one by one in the inner ear in 10 different recesses gently drilled in the bony cochlea. This device was placed in 46 patients between 1992 and 1994, including 8 young children (aged 2-9 years, mean 5 years) and 9 patients with total cochlear obstruction.

Child↗
PubMed1995

[Signal processing and clinical results with the French cochlear implant Digisonic].

The Digisonic is a totally digitised multichannel cochlear implant remarkable for the versatility of its sound signal processing. Owing to its flexible and articulated array, its 15 electrodes are usually introduced in the scala tympani. A special version of this device has been designed to be used in case of total obstructed cochlea. It consists of separated electrodes which may be inserted one by one in the inner ear in different holes gently drilled in the bony cochlea. The possibilities of the microprocessor allow the speech therapist to carefully select the best width and mean value of each frequency band respectively devoted to each functional electrode. These parameters may be adapted to progressively improve the patient's hearing performances as a function of his phonemic discrimination and or the number and the tonotopy of his functional electrodes. Moreover, owing to the versatility of this digitised emitter a lot of speech coding strategies may be easily programmed as a function of eventual desiderata. Its high miniaturisation leads this implant to be particularly useful for young children. Results of our 38 first implanted patients (age 2-74; mean 42) including 7 cases of totally obstructed cochlea are reported.

Adolescent↗
PubMed1995

[Cochlear implants and total cochlear obstruction].

Total cochlea obstruction is not a contraindication for cochlear implant. We report our experience owing to the single channel cochlear implant Monosonic (9 cases), partial insertion of the electrodes-array (3 cases: 1 Digisonic and 2 minisystem) and, more recently the separate electrodes version of the Digisonic (6 cases). This new device is encouraging because it supplies 2/5 patients with telephone use.

Adolescent↗
PubMed1995

[Evaluation protocol of cochlear implants in children under 5 years of age].

Special tests are necessary to assess the cochlear implant efficacy on a prelingually deaf child implanted before age 5 y. We propose to quantify comportment, comprehension, auditory perception and expression as percentage of a same age normally hearing child's scores. The particular items are detailed.

Age Factors↗
PubMed1992

[Improvement of clinical results by digitalization of a single channel cochlear implant].

For 1973 we have been among the first to claim the multichannel cochlear implant superiority regarding single channel efficacy. However we actually thing that single channel cochlear implant is indispensable in case of total ossified cochlea, and very useful when efficacy/coast ratio must be considered. In order to narrow the gap between multi and single channel device efficacy, we used the new microprocessors possibilities to digitalize the analogic emietter of the single channel system, which we designed in 1987. Owing to a PC keyboard the new emietter allows the speech therapist to select the frequency band width of the input signal, and to determine the threshold level and the dynamic value as a function of six steps values of the stimulus wave frequency. These improvements supply the patient with a better speech intelligibility excepted for vowels discrimination. Comparison of clinical results obtained through the two analogic and digital systems are reported on 4 post lingually and 4 pre lingually deaf patients.

Adolescent↗
PubMed1992

[Indications and results of cochlear implants in young children].

In order to determine the criteria for patient selection and the preoperative prognostic factors for hearing recovery after cochlear implants in young totally dead children, the results of hearing rehabilitation were studied in 15 children who had undergone cochlear implantation at from 2 to 9 years of age. The choice of implant is determined by the permeability of the cochlear duct. A multi-system should be used, except when the cochlea is totally ossified. The reliability and efficacy of mono and multi system implants make it possible to offer a solution to the urgent therapeutic problems posed by total deafness in the young child.

Age Factors↗
PubMed1991

[The choice between mono- and multielectrode implants in rehabilitation of total deafness in young children].

We underline the necessity to supply a prelingually totally deaf patient with some sound information before the critical age of about 5-8 years, which we had previously experimentally demonstrated on the guinea pig. Multichannel cochlear implant is the most efficient and must be placed most of cases. However, specially in case of total ossified cochlea, single channel cochlear implant is the only usefull. The respective indications of these two different systems are discussed as a function of pronostic preoperative data, cochlear total ossification, and financial considerations. The decision to supply a young totally deaf child with a cochlear implant must be considered as an emergency.

Age Factors↗
PubMed1990

["Monosonic" one canal digital implant].

In order to decrease the gap between the single and multichannel cochlear implant efficacy we tried to improve the speech coding strategy of the Monomac, the constant current single channel system which we designed in 1987. Owing to a research computerized system, different strategies have been successively studied in the laboratory on 12 new implanted patients during the first weeks of the post-operative period to avoid habituation differences. Results led us to design a miniaturized digital emitter, the Monosonic. This emitter allows the speech therapist to program the frequency band wideness (80-1000 Hz) of the transmitted information, and the threshold level and dynamic range of the stimulating square wave as a function of its frequency. Other strategies are discussed, which have not been yet studied, but may be also programmed.

Acoustic Stimulation↗
PubMed1990

[Presentation of a French language protocol for the evaluation of communication improvement in the deaf following implantation].

We have been led to drawing up a procedure of assessment of communication as restored by implantation. This procedure is simple, and can be used by all teams, however complex the material implanted is. It can be implemented for children as well as adults, and for both pre- and post-speech deafness. Our staging allows integrating the implanted patient into the classical description of deafness, while retaining the specific features of electrical stimulation.

Auditory Perception↗
PubMed1990

[Results and indications of cochlear implant in 19 cases of total pre-speech deafness].

From June, 1987, to January, 1900, 19 patients aged 3 to 56 years have been rehabilitated for total deafness occurring prior to the acquisition of speech, ie. before age 2, whatever its cause. Some degree of hearing was achieved in all cases. However, the rate and steadiness of progress in auditory recognition, the daily period of use of the device and the changes in the behavior were inversely proportional to the patient's age. This leads to proposing cochlear implants for all patients, especially children, and all the more largely as they are young.

Adolescent↗
PubMed1988

[The monochannel Monomac and multichannel Minimac cochlear implants].

Monomac monochannel and Minimac multichannel cochlear implants bring to the remaining hearing fibers sound information that is previously converted into adequate electric signals. Both function at constant currents. The Monomac monocanal system possesses only one electrode implanted either inside or outside the cochlea and sends off sound of basic laryngeal rythm to all the nervous fibers. The Minimac is entirely numerical and sends off the whole of the sound information by splitting it into 15 frequency tracks, to 15 electrodes inserted within the scala tympani by means of an electrode-holder. Programming allows for selecting specific values from each frequency track and thus regulating the needed compression individually. Both these implants (Monomac and Minimac) work no conflictlessly but complementarily to each other because they answer different, well-defined clinical needs.

Cochlear Implants↗
PubMed1988

[Operative indications of total deafness].

Rehabilitation of patients with total hearing loss through surgical implantation of intracochlear devices is warranted only in cases for which deafness is absolutely not relieved by conventional hearing prostheses. Furthermore, it is required that the patient respond positively to the electrostimulation test of the round window, be strongly motivated, as well as present a high index of socialization. These three parameters will also determine the type of implant to be used, i.e. mono- or multielectrode, as well as particular indications relating to children.

Acoustic Stimulation↗
PubMed1988

[Changes in the speaking fundamental frequency after cochlear implantation].

Speaking fundamental frequency (Fo) changes have been studied in 12 patients suffering from total post-lingual deafness and having been supplied with the multichannel cochlear implant CHORIMAC-12. Fo is significantly lower after implantation. But Fo variance changes depend on the laryngeal associated pathology.

Cochlear Implants↗
PubMed1988

[Clinical results of the multielectrode cochlear implant in the rehabilitation of 27 cases of acquired total deafness].

Multi-electrode cochlear implants allow verbal discrimination without lip reading in a manner dependent directly on the liminal threshold value during the preoperative electrical stimulation of round window test, and the quality of socialization and motivation of the patient. Overall auditory performances of 27 patients rehabilitated in this way are reviewed and compared with those obtained by other teams and other apparatuses.

Adult↗
PubMed1987

Indications for multi- or single-channel cochlear implant for rehabilitation of total deafness.

Only totally deaf patients who do not experience improvement when using classical hearing aids are candidates for a cochlear implant. Preoperative assessment of potential benefits of a cochlear implant may improve selection of patients with pre- or postlingual total deafness, so that the most appropriate system can be implanted. The psychological status of potential candidates for implantation is particularly important because the results of postoperative re-education depends on motivation of the patient. The Round Window electrical stimulation test supplies us with important and measurable data (electrical threshold level, tone decay test). The duration of deafness, the degree of the deafness, and the cochlear tomodensitometry do not affect the decision to implant a cochlear device, (i.e., since the socialization level of the patient is a considerable factor). Preoperative assessment of the patient is very useful. As a result of our experience in 115 implanted cases suffering from pre- and postlingual deafness, we are now able to predict the good or bad results in our patients. Therefore, in patients who have many adverse factors for recovery, it seems to us more reasonable and cheaper to implant a single-channel system instead of a multichannel system, which must be reserved for patients who should do well. In very young children, the most appropriate system seems to be extra cochlear single-channel implant.

Cochlear Implants↗