Bruno Frachet

A middle ear implant, the symphonix Vibrant soundbridge: Retrospective study of the first 125 patients implanted in France

Objective The Vibrant Soundbridge is an active semi-implantable middle ear implant for the rehabilitation of patients with a sensorineural hearing loss who are not able to derive adequate benefit from conventional hearing aids. A retrospective study was performed to assess the overall level of satisfaction of implanted patients and to investigate the potential determinants of postoperative success. Study Design A retrospective survey of audiological data from repeated measures and subjective data from self-assessment scales administered postoperatively was conducted to determine the degree of benefit and satisfaction for Vibrant Soundbridge implantees. Setting Twenty-one tertiary referral and teaching hospitals. Subjects The first 125 VSB implantees implanted in France between August 1997 and May 2001 were included in the study. Results No clinically significant change was observed for residual hearing postoperatively. Most patients (83%) reported they were either satisfied or very satisfied with the Vibrant Soundbridge. Analysis of correlation revealed a moderate correlation (Pearson coefficient r = 0.59) between the degree of benefit reported via the patient survey and the degree of benefit reported via the Glasgow Benefit Inventory. A moderate correlation (Pearson coefficient r = 0.66) was observed between speech comprehension scores in quiet for the preoperative unaided condition and the postoperative aided Vibrant Soundbridge condition. No correlation was observed between subjective reports of satisfaction postoperatively and performance on preoperative objective tests or patient characteristics. Conclusion The results indicate a high level of satisfaction with the VSB as a treatment of sensorineural hearing impairment in patients with a wide range of characteristics. Preoperative scores for unaided speech comprehension tests in quiet may be a potential indicator of success on aided Vibrant Soundbridge speech comprehension tests postoperatively but do not reflect patient satisfaction with the device reported on self-assessment scales.

Improvement of cognitive function after cochlear implantation in elderly patients

IMPORTANCEnThe association between hearing impairment and cognitive decline has been established; however, the effect of cochlear implantation on cognition in profoundly deaf elderly patients is not known.nnnOBJECTIVEnTo analyze the relationship between cognitive function and hearing restoration with a cochlear implant in elderly patients.nnnDESIGN, SETTING, AND PARTICIPANTSnProspective longitudinal study performed in 10 tertiary referral centers between September 1, 2006, and June 30, 2009. The participants included 94 patients aged 65 to 85 years with profound, postlingual hearing loss who were evaluated before, 6 months after, and 12 months after cochlear implantation.nnnINTERVENTIONSnCochlear implantation and aural rehabilitation program.nnnMAIN OUTCOMES AND MEASURESnSpeech perception was measured using disyllabic word recognition tests in quiet and in noise settings. Cognitive function was assessed using a battery of 6 tests evaluating attention, memory, orientation, executive function, mental flexibility, and fluency (Mini-Mental State Examination, 5-word test, clock-drawing test, verbal fluency test, d2 test of attention, and Trail Making test parts A and B). Quality of life and depression were evaluated using the Nijmegen Cochlear Implant Questionnaire and the Geriatric Depression Scale-4.nnnRESULTSnCochlear implantation led to improvements in speech perception in quiet and in noise (at 6 months: in quiet, 42% score increase [95% CI, 35%-49%; Pu2009<u2009.001]; in noise, at signal to noise ratio [SNR] +15 dB, 44% [95% CI, 36%-52%, Pu2009<u2009.001], at SNR +10 dB, 37% [95% CI 30%-44%; Pu2009<u2009.001], and at SNR +5 dB, 27% [95% CI, 20%-33%; Pu2009<u2009.001]), quality of life, and Geriatric Depression Scale-4 scores (76% of patients gave responses indicating no depression at 12 months after implantation vs 59% before implantation; Pu2009=u2009.02). Before cochlear implantation, 44% of the patients (40 of 91) had abnormal scores on 2 or 3 of 6 cognition tests. One year after implant, 81% of the subgroup (30 of 37) showed improved global cognitive function (no or 1 abnormal test score). Improved mean scores in all cognitive domains were observed as early as 6 months after cochlear implantation. Cognitive performance remained stable in the remaining 19% of the participants (7 of 37). Among patients with the best cognitive performance before implantation (ie, no or 1 abnormal cognitive test score), 24% (12 of 50) displayed a slight decline in cognitive performance. Multivariate analysis to examine the association between cognitive abilities before implantation and the variability in cochlear implant outcomes demonstrated a significant effect only between long-term memory and speech perception in noise at 12 months (SNR +15 dB, Pu2009=u2009.01; SNR +10 dB, Pu2009<u2009.001; and SNR +5 dB, Pu2009=u2009.02).nnnCONCLUSIONS AND RELEVANCEnRehabilitation of hearing communication through cochlear implantation in elderly patients results in improvements in speech perception and cognitive abilities and positively influences their social activity and quality of life. Further research is needed to assess the long-term effect of cochlear implantation on cognitive decline.

European multi-centre study of the Nucleus Hybrid L24 cochlear implant

Abstract Objectives: To investigate the preservation of residual hearing in subjects who received the Nucleus Hybrid L24 cochlear implant. To investigate the performance benefits up to one year post-implantation in terms of speech recognition, sound quality, and quality of life. Design: Prospective, with sequential enrolment and within-subject comparisons. Post-operative performance using a Freedom Hybrid sound processor was compared with that of pre-operative hearing aids. Study sample: Sixty-six adult hearing-impaired subjects with bilateral severe-to-profound high frequency hearing loss. Results: Group median increase in air-conduction thresholds in the implanted ear for test frequencies 125–1000 Hz was < 15 dB across the population; both immediately and one year post-operatively. Eighty-eight percent of subjects used the Hybrid processor at one year post-op. Sixty-five percent of subjects had significant gain in speech recognition in quiet, and 73% in noise (≥ 20 percentage points/2 dB SNR). Mean SSQ subscale scores were significantly improved (+ 1.2, + 1.3, + 1.8 points, p < 0.001), as was mean HUI3 score (+ 0.117, p < 0.01). Combining residual hearing with CI gave 22−26 %age points mean benefit in speech recognition scores over CI alone (p < 0.01). Conclusions: Useful residual hearing was conserved in 88% of subjects. Speech perception was significantly improved over preoperative hearing aids, as was sound quality and quality of life.

Middle ear adenoma. A tumor displaying mucinous and neuroendocrine differentiation.

Middle ear adenoma (MEA) is a distinctive, rare entity that appears to be derived from the lining epithelium of the middle ear mucosa. We report four cases of MEA displaying the typical histologic growth pattern. Two distinct tumor cell immunophenotypes were identified in all cases; the first type exhibited positivity with antiepithelial membrane antigen and anti-keratin antibodies, and the second type showed immunoreactivity with antikeratin, anti-vimentin, and anti-neuron-specific enolase antibodies. Ultrastructural studies revealed bidirectional mucinous and neuroendocrine differentiation, demonstrated by the presence of two distinct cell types containing apically located mucous granules and basally concentrated neuroendocrine granules, respectively. The presence of neuroendocrine differentiation was supported by the immunohistochemical detection of vasoactive intestinal polypeptide in the tumor cells in one case and neuronspecific enolase in three cases. These findings suggests that the potential for mixed mucinous/neuroendocrine differentiation described in other endodermally derived tumors also exists in middle ear mucosa. We also believe that the rare lesions diagnosed as primary carcinoid tumors of the middle ear might in fact be MEA with predominant or only neuroendocrine differentiation. The clinical course of our four cases and our review of the pertinent literature confirm the benign nature of MEA and indicate that these tumors should be treated by complete local excision without additional therapy.

Comparison of three types of French speech­in­noise tests: A multi­center study

Abstract Objective: To compare results on the everyday sentence test ‘FIST’, the new closed-set sentence test ‘FrMatrix’, and the digit triplet screening test ‘FrDigit3’. Design: First, the FrMatrix was developed and normative values were obtained. Subsequently, speech reception thresholds (SRTs) for the three types of tests were gathered at four study centers representing different geographic regions in Belgium and France. Study sample: Fifty-seven normal-hearing listeners took part in the normative study of the FrMatrix, and 118 subjects, with a wide range of hearing thresholds, participated in the comparative study. Results: Homogenizing the individual words of the FrMatrix with regard to their intelligibility resulted in a reference SRT of −6.0 (±0.6) dB SNR and slope at the SRT of 14.0 %/dB. The within-subject variability was only 0.4 dB. Comparison of the three tests showed high correlations between the SRTs mutually (>0.81). The FrMatrix had the highest discriminative power, both in stationary and in fluctuating noise. For all three tests, differences across the participating study centers were small and not significant. Conclusions: The FIST, the FrMatrix, and the FrDigit3 provide similar results and reliably evaluate speech recognition performance in noise both in normal-hearing and hearing-impaired listeners.

The French digit triplet test: A hearing screening tool for speech intelligibility in noise

Abstract A French speech intelligibility screening test in noise that applies digit triplets as stimuli has been developed and evaluated for both telephone and broadband headphone use. After optimizing the speech material based on the intelligibility of the individual digits, norms for normal-hearing subjects were established. speech reception thresholds (SRTs) of −6.4 ± 0.4 and −10.5 ± 0.3 dB SNR, and slopes of 17.1 and 27.1 %/dB were obtained for telephone and broadband headphone presentation, respectively. The French digit triplet test by telephone was then implemented as an automatic self-screening test by home telephone, and further evaluated in normal-hearing and hearing-impaired listeners. A test-retest variability of 0.7 dB was found and the correlation between SRT and pure-tone average (PTA0.5,1,2,4) was 0.77. One month after launching the test, 20 000 calls were registered. It can be concluded that both versions of the newly developed test have steep slopes and small SRT differences across normal-hearing listeners. The screening test by telephone is highly reliable and proves to fulfill the need for an easily accessible and objective hearing screening. Sumario Se desarrolló y evaluó una prueba de tamiz de inteligibilidad del lenguaje en ruido, utilizando ternas de dígitos como estímulo, tanto para teléfono como para auriculares de banda ancha. Después de optimizar el material lingüístico basado en la inteligibilidad de los dígitos individuales, se establecieron las normas para los sujetos normoyentes. Se obtuvieron umbrales de recepción del lenguaje (SRTs) de -6.4 ± 0.4 y -10.5 ± 0.3dB SNR y pendientes de 17.1 y 27.1%/dB para teléfono y auriculares de banda ancha, respectivamente. Se implementó la prueba de terna de dígitos en francés por teléfono como una prueba de tamiz autoaplicable por teléfono en casa y después se evaluó en normoyentes e hipoacúsicos. Se encontró una variabilidad de test-re-test de 0.7 dB y la correlación entre SRT y el promedio de tonos puros (PTA0.5,1,2,4) fue de 0.77. Un mes después de lanzar la prueba, se registraron 20,000 llamadas. Se puede concluir que ambas versiones de la prueba recientemente desarrollada tiene pendientes pronunciadas y pequeñas diferencias del SRT entre los normoyentes. La prueba de tamiz por teléfono es altamente confiable y demuestra que satisface las necesidades de una prueba de tamiz auditivo fácil, accesible y objetiva.

Expression of NMDA, AMPA and GABAA receptor subunit mRNAs in the rat auditory brainstem. I. Influence of early auditory deprivation

Impact of early post-natal deafening on auditory pathways was investigated in newborn rats deafened by daily amikacin injections from P7 to P16 inducing a complete destruction of the organ of Corti. The expression of mRNAs encoding N-methyl-D-aspartate (NMDA), alpha-amino-3-hydroxy-5-methyl-4-isoxazole (AMPA) and gamma-aminobutyric acid type A (GABA(A)) receptor subunits was then studied by in situ hybridization in the dorsal and ventral cochlear nucleus and in the central nucleus of the inferior colliculus (CNIC). Early post-natal deafening decreased bilaterally the expression of mRNAs encoding NR1, NR2a, NR2b and flop isoforms of AMPA receptors. On the contrary, it increased the expression of mRNAs encoding some GABA(A) subunits (alpha1, beta1, gamma2) and flip isoforms of AMPA receptors. These changes were more pronounced in cochlear nuclei than in CNIC. They suggest that auditory sensation is essential in the normal development of central auditory pathways.

Mismatch negativity: a tool for the assessment of stimuli discrimination in cochlear implant subjects

OBJECTIVESnThe performance of cochlear implants varies among users. This variability may be due to the ability to process auditory information. The mismatch negativity should provide an index of discrimination in cochlear implantees (Kraus N, McGee T, Carrell T, Sharma A. Neurophysiologic bases of speech discrimination. Ear Hear. 1995;16:19-37). Our aim was to analyze MMN in cochlear implant (Digisonic) subjects to assess electrode discrimination and to study the relationship between MMN and speech performance.nnnMETHODSnThe mismatch was determined by stimulating three pairs of different electrodes. Two sessions were performed with both standard and deviant stimuli reversed. Speech recognition abilities were evaluated using 4 speech tests. The statistics included the results of 6 subjects. They indicated that MMN may be obtained when stimulating two different electrodes. A difference occurred between standard and deviant stimuli within a session but also when the response to the deviant stimulus was compared to the response of the same stimulus in a standard condition, validating the discrimination process. MMN latency was about 140 ms, and amplitude about -2.8 microV. No differences were shown with respect to electrode spacing. No relationship between MMN and speech performance was found. A clinical application of this method might be to assess the auditory processing of electrical stimuli in congenitally deaf subjects at the pre-implantation stage.

Auditory rehabilitation with cochlear implantation in patients with neurofibromatosis type 2.

Conclusions: New technological developments will most probably improve the efficiency of auditory brainstem implantation (ABI). Meanwhile, cochlear implantation in patients who have undergone prior reductive surgery, and who have maintained a positive electric stimulation, is an excellent alternative for rehabilitating complete and bilateral hearing loss in patients with neurofibromatosis type 2 (NF2). Auditory results are far better than those reported after ABI. Long-term follow-up will be necessary to demonstrate the validity of this strategy. Objectives: ABIs restore some degree of auditory perception in NF2 patients with bilateral and complete hearing loss, but results are often inadequate for maintaining social and professional activities. The aim of this study was to report the results of auditory rehabilitation by cochlear implantation in three cases of NF2. Patients and methods: This was a retrospective study undertaken in a tertiary referral center. The first patient had undergone previous surgery for a left grade III vestibular schwannoma (VS) and then underwent irradiation for a right grade I VS. Two years after irradiation, he suddenly lost his remaining hearing. Electric promontory stimulation was positive and cochlear implantation was performed. The second patient had undergone surgery for a left grade III VS and followed for a right grade II VS. She suddenly lost her remaining hearing. A cytoreductive surgery was performed and the cochlear nerve was preserved. Postoperative electric stimulation was positive. She was then implanted with a cochlear implant. The third patient presented with a right stage III and a left stage I VS. She first underwent a subtotal removal of the left VS with immediate cochlear implantation. She then underwent removal of the right VS stage III with no possible preservation of the cochlear nerve. Results: All three patients had excellent postoperative speech performance and were back to work 3 months after implantation. Imaging follow-ups at 4, 2, and 1 year, respectively, do not show any evolution of the tumor.

Interactive evolution for cochlear implants fitting

Cochlear implants (CI) are devices that become more and more sophisticated and adapted to the need of patients, but at the same time they become more and more difficult to parameterize. After a deaf patient has been surgically implanted, a specialised medical practitioner has to spend hours during months to precisely fit the implant to the patient. This process is a complex one implying two intertwined tasks: the practitioner has to tune the parameters of the device (optimisation) while the patient’s brain needs to adapt to the new data he receives (learning). This paper presents a study that intends to make the implant more adaptable to environment (auditive ecology) and to simplify the process of fitting. Real experiments on volunteer implanted patients are presented, that show the efficiency of interactive evolution for this purpose.