ABSTRACT
INTRODUCTION: Cochlear implantation is a recent approach proposed to treat single-sided deafness (SSD) and asymmetric hearing loss (AHL). Several cohort studies showed its effectiveness on tinnitus and variable results on binaural hearing. The main objective of this study is to assess the outcomes of cochlear implantation and other treatment options in SSD/AHL on quality of life. METHODS: This prospective multicenter study was conducted in 7 tertiary university hospitals and included an observational cohort study of SSD/AHL adult patients treated using contralateral routing of the signal (CROS) hearing aids or bone-anchored hearing systems (BAHSs) or who declined all treatments, and a randomized controlled trial in subjects treated by cochlear implantation, after failure of CROS and BAHS trials. In total, 155 subjects with SSD or AHL, with or without associated tinnitus, were enrolled. After 2 consecutive trials with CROS hearing aids and BAHSs on headband, all subjects chose any of the 4 treatment options (abstention, CROS, BAHS, or cochlear implant [CI]). The subjects who opted for a CI were randomized between 2 arms (CI vs. initial observation). Six months after the treatment choice, quality of life was assessed using both generic (EuroQoL-5D, EQ-5D) and auditory-specific quality-of-life indices (Nijmegen Cochlear implant Questionnaire [NCIQ] and Visual Analogue Scale [VAS] for tinnitus severity). Performances for speech-in-noise recognition and localization were measured as secondary outcomes. RESULTS: CROS was chosen by 75 subjects, while 51 opted for cochlear implantation, 18 for BAHSs, and 11 for abstention. Six months after treatment, both EQ-5D VAS and auditory-specific quality-of-life indices were significantly better in the "CI" arm versus "observation" arm. The mean effect of the CI was particularly significant in subjects with associated severe tinnitus (mean improvement of 20.7 points ± 19.7 on EQ-5D VAS, 20.4 ± 12.4 on NCIQ, and 51.4 ± 35.4 on tinnitus). No significant effect of the CI was found on binaural hearing results. Before/after comparisons showed that the CROS and BAHS also improved significantly NCIQ scores (for CROS: +7.7, 95% confidence interval [95% CI] = [4.5; 10.8]; for the BAHS: +14.3, 95% CI = [7.9; 20.7]). CONCLUSION: Cochlear implantation leads to significant improvements in quality of life in SSD and AHL patients, particularly in subjects with associated severe tinnitus, who are thereby the best candidates to an extension of CI indications.
Subject(s)
Cochlear Implantation , Cochlear Implants , Deafness , Hearing Loss, Unilateral , Hearing Loss , Speech Perception , Adult , Deafness/surgery , Hearing Loss, Unilateral/surgery , Humans , Prospective Studies , Quality of Life , Treatment OutcomeABSTRACT
OBJECTIVES: To describe the treatment choice in a cohort of subjects with single-sided deafness (SSD) and asymmetric hearing loss (AHL). To assess the reliability of the treatment trials. DESIGN: In this national, multicentre, prospective study, the choice of subjects was made after two consecutive trials of Contralateral Routing Of the Signal (CROS) hearing aids and a Bone Conduction Device (BCD) on a headband. Subjects could proceed with one of these two options, opt for cochlear implantation or decline all treatments. SETTING: Seven tertiary university hospitals. PARTICIPANTS: One hundred fifty-five subjects with SSD or AHL fulfilling the candidacy criteria for cochlear implantation, with or without associated tinnitus. MAIN OUTCOME MEASURES: After the two trials, the number of subjects choosing each option was described. Repeated assessments of both generic and auditory-specific quality of life were conducted, as well as hearing assessments (speech recognition in noise and horizontal localization). RESULTS: CROS was chosen by 75 subjects, followed by cochlear implantation (n = 51), BCD (n = 18) and abstention (n = 11). Patients who opted for cochlear implantation had a poorer quality of life (P = .03). The improvement of quality of life indices after each trial was significantly associated with the final treatment choice (P = .008 for generic indices, P = .002 for auditory-specific indices). The follow-up showed that this improvement had been overestimated in the CROS group, with a long-term retention rate of 52.5%. CONCLUSIONS: More than one third of SSD/AHL subjects are unsatisfied after CROS and BCD trials. Repeated quality of life assessments help counselling the patient for his/her treatment choice.
Subject(s)
Hearing Loss, Unilateral/rehabilitation , Bone Conduction , Choice Behavior , Cochlear Implants , Female , France , Hearing Aids , Humans , Male , Middle Aged , Prospective Studies , Quality of Life , Speech Reception Threshold TestABSTRACT
HYPOTHESIS: Evaluate the benefit of preoperative surgical planning using computed tomography (CT) for atraumatic cochlear implantation. BACKGROUND: The surgical technique has a direct impact on hearing and structure preservation. Much interest has been given to depth of electrode insertion. We focused on electrode diameter depending on exposure of round window membrane (RWM) as calculated on preoperative CT. METHODS: Measurements were calculated radiologically and anatomically on 10 temporal bones. Results were compared with CT scans of a control population. Thereafter, preoperative CT scan measurements were applied to seven additional temporal bones that underwent cochlear implantation with the insertion of two electrodes of different diameters (14 implantations) to validate radiological analysis. RESULTS: RWM size was 1.5â±â0.2âmm on CT and 1.2â±â0.2âmm during dissection; posterosuperior bony overhang of round window niche was 1.1â±â0.1âmm on CT and 1.3â±â0.2âmm during dissection. There was no statistically significant difference between radiological and anatomical measurements and between radiological measurements of cadaveric temporal bones and control population (pâ>â0.05 for both). Also, preoperative surgical planning was reliable in the seven temporal bones implanted with two electrode types (accuracy 93%, sensitivity 85.7%, specificity 100%) yielding no damage to intracochlear structures. CONCLUSION: Difficulties to access RWM could be predicted on preoperative CT of temporal bones and control population, which correlated well with anatomical dissections and surgical findings during cochlear implantation. According to CT planning, electrode insertion through RWM was feasible in most patients, with or without drilling posterosuperior bony overhang of round window niche. Promontory cochleostomy could be recommended when electrode apical diameter exceeded maximal RWM exposure. There was no case of intracochlear trauma on microdissections.
Subject(s)
Cochlear Implantation/methods , Surgery, Computer-Assisted/methods , Temporal Bone/diagnostic imaging , Temporal Bone/surgery , Tomography, X-Ray Computed/methods , Cochlea/surgery , Cochlear Implants , Female , Humans , Male , Round Window, Ear/diagnostic imaging , Round Window, Ear/surgeryABSTRACT
OBJECTIVES: To assess the feasibility of using cone-beam computed tomography (CBCT) in young children with cochlear implants (CIs) and study the effect of intracochlear position on electrophysiological and behavioral measurements. METHODS: A total of 40 children with either unilateral or bilateral cochlear implants were prospectively included in the study. Electrode placement and insertion angles were studied in 55 Cochlear® implants (16 straight arrays and 39 perimodiolar arrays), using either CBCT or X-ray imaging. CBCT or X-ray imaging were scheduled when the children were leaving the recovery room. We recorded intraoperative and postoperative neural response telemetry threshold (T-NRT) values, intraoperative and postoperative electrode impedance values, as well as behavioral T (threshold) and C (comfort) levels on electrodes 1, 5, 10, 15 and 20. RESULTS: CBCT imaging was feasible without any sedation in 24 children (60%). Accidental scala vestibuli insertion was observed in 3 out of 24 implants as assessed by CBCT. The mean insertion angle was 339.7°±35.8°. The use of a perimodiolar array led to higher angles of insertion, lower postoperative T-NRT, as well as decreased behavioral T and C levels. We found no significant effect of either electrode array position or angle of insertion on electrophysiological data. CONCLUSION: CBCT appears to be a reliable tool for anatomical assessment of young children with CIs. Intracochlear position had no significant effect on the electrically evoked compound action potential (ECAP) threshold. Our CBCT protocol must be improved to increase the rate of successful investigations.
Subject(s)
Cochlear Implants , Cone-Beam Computed Tomography/methods , Scala Tympani/diagnostic imaging , Scala Vestibuli/diagnostic imaging , Child, Preschool , Cochlear Implantation , Electric Impedance , Electrophysiological Phenomena , Female , Humans , Infant , Male , Postoperative Period , Treatment OutcomeABSTRACT
The quality of the prosthetic-neural interface is a critical point for cochlear implant efficiency. It depends not only on technical and anatomical factors such as electrode position into the cochlea (depth and scalar placement), electrode impedance, and distance between the electrode and the stimulated auditory neurons, but also on the number of functional auditory neurons. The efficiency of electrical stimulation can be assessed by the measurement of e-CAP in cochlear implant users. In the present study, we modeled the activation of auditory neurons in cochlear implant recipients (nucleus device). The electrical response, measured using auto-NRT (neural responses telemetry) algorithm, has been analyzed using multivariate regression with cubic splines in order to take into account the variations of insertion depth of electrodes amongst subjects as well as the other technical and anatomical factors listed above. NRT thresholds depend on the electrode squared impedance (ß = -0.11 ± 0.02, P < 0.01), the scalar placement of the electrodes (ß = -8.50 ± 1.97, P < 0.01), and the depth of insertion calculated as the characteristic frequency of auditory neurons (CNF). Distribution of NRT residues according to CNF could provide a proxy of auditory neurons functioning in implanted cochleas.
Subject(s)
Auditory Threshold/physiology , Cochlear Implants , Models, Neurological , Neurons/physiology , Adolescent , Adult , Electrodes, Implanted , Humans , Linear Models , Male , Middle Aged , Multivariate Analysis , Young AdultABSTRACT
OBJECTIVES: With cochlear implantation now a routine procedure, reimplantation is becoming more commonplace for medical/surgical complications or device malfunctions. This study investigated the indications for reimplantation and the auditory outcomes following reimplantation surgery in prelingually-deafened children. METHODS: Of the 539 prelingually deafened children implanted between 1990 and 2013, 45 were reimplanted (8.3% of implantations). Causes of reimplantation, type of device and angle of insertion at initial implantation were recorded, as well as type of implant reinserted, number of electrodes inserted and angle of insertion (calculated on cone beam computed tomography) on reimplantation, and finally any surgical findings. Speech perception test scores (phonetically balanced kindergarten (PBK) words, open-set sentence testing in quiet and in noise (S/N+ 10 dB SNR), and speech tracking scores) were obtained 1, 2 and 3 years after reimplantation, and compared against the best speech recognition score obtained with the first implant before failure. RESULTS: Medical reasons for reimplantation were found in 10 cases (22.2%). A malfunctioning device had occurred in 35 cases (77.7%) including hard failure in 24 and soft failure in 11. Complete insertion was achieved in the scala tympani in 42 cases and in the scala vestibuli in one case; partial insertion occurred in the remaining two cases. In two cases, one or two electrode rings snatched off from the electrode array during removal. The mean insertion angle was 330.5° before surgery and 311.8° after reimplantation (no statistical difference p=0.48). The postoperative speech perception outcome measures showed no significant difference to the best score before reimplantation. Angle of insertion, type of device and etiology of deafness did not influence the results. The PBK performance improved over 10% in 43.2% of children, was similar in 40.5%, and showed a more than 10% decrease in 16.2% of children after reimplantation. The latter decline in performance was explained for some children by a partial insertion. CONCLUSIONS: Reimplantation has no negative effect on auditory outcome. In rare cases, speech perception outcome may not improve, requiring a specific rehabilitation program.
Subject(s)
Cochlear Implantation/methods , Cochlear Implants , Deafness/surgery , Speech Perception , Adolescent , Child , Child, Preschool , Cochlear Implantation/instrumentation , Deafness/etiology , Deafness/rehabilitation , Female , Humans , Male , Phonetics , Prosthesis Failure , Reoperation , Young AdultABSTRACT
HYPOTHESIS: To evaluate the feasibility and the results of insertion of two types of electrode arrays in a robotically assisted surgical approach. BACKGROUND: Recent publications demonstrated that robot-assisted surgery allows the implantation of free-fitting electrode arrays through a cochleostomy drilled via a narrow bony tunnel (DCA). We investigated if electrode arrays from different manufacturers could be used with this approach. METHODS: Cone-beam CT imaging was performed on five-cadaveric heads after placement of fiducial screws. Relevant anatomical structures were segmented and the DCA trajectory, including the position of the cochleostomy, was defined to target the center of the scala tympani while reducing the risk of lesions to the facial nerve. Med-El Flex 28 and Cochlear CI422 electrodes were implanted on both sides, and their position was verified by cone-beam CT. Finally, temporal bones were dissected to assess the occurrence of damage to anatomical structures during DCA drilling. RESULTS: The cochleostomy site was directed in the scala tympani in 9 of 10 cases. The insertion of electrode arrays was successful in 19 of 20 attempts. No facial nerve damage was observed. The average difference between the planned and the postoperative trajectory was 0.17 ± 0.19 mm at the level of the facial nerve. The average depth of insertion was 305.5 ± 55.2 and 243 ± 32.1 degrees with Med-El and Cochlear arrays, respectively. CONCLUSIONS: Robot-assisted surgery is a reliable tool to allow cochlear implantation through a cochleostomy. Technical solutions must be developed to improve the electrode array insertion using this approach.
Subject(s)
Cochlear Implantation/methods , Cochlear Implants , Otologic Surgical Procedures/methods , Robotics , Bone Screws , Cadaver , Cone-Beam Computed Tomography , Electrodes, Implanted , Feasibility Studies , Humans , Scala Tympani/diagnostic imaging , Scala Tympani/surgery , Surgical Instruments , Treatment OutcomeABSTRACT
Frequency-place mismatch often occurs after cochlear implantation, yet its effect on speech perception outcome remains unclear. In this article, we propose a method, based on cochlea imaging, to determine the cochlear place-frequency map. We evaluated the effect of frequency-place mismatch on speech perception outcome in subjects implanted with 3 different lengths of electrode arrays. A deeper insertion was responsible for a larger frequency-place mismatch and a decreased and delayed speech perception improvement by comparison with a shallower insertion, for which a similar but slighter effect was noticed. Our results support the notion that selecting an electrode array length adapted to each individual's cochlear anatomy may reduce frequency-place mismatch and thus improve speech perception outcome.
Subject(s)
Cochlea/diagnostic imaging , Cochlear Implants , Deafness/rehabilitation , Pitch Perception , Speech Perception , Adolescent , Adult , Cochlea/surgery , Cochlear Implantation/methods , Female , Humans , Male , Middle Aged , Tomography, X-Ray Computed , Treatment Outcome , Young AdultABSTRACT
OBJECTIVE: To demonstrate the feasibility and reliability of simultaneous binaural recording of auditory steady-state responses (ASSR) in young children using narrow-band CE-Chirps as stimuli. DESIGN: Prospective cohort study comparing ASSR thresholds to four frequency stimuli (0.5, 1, 2, and 4 kHz), with click-evoked auditory brainstem responses (ABR) and behavioral response audiometry. STUDY SAMPLE: Thirty-two young children (mean age 7.4 ± 5.2 months) referred for auditory assessment were evaluated. RESULTS: The mean duration for ABR recordings was 13.3 ± 7.2 min versus 22.9 ± 15.8 min for ASSR (p < 0.01). ASSR (means of 2 and 4 kHz thresholds) were highly correlated with ABR thresholds (R2 = 0.935, p < 0.001), though significantly different (3 ± 10.7 dB, p = 0.02). ASSR (means of 0.5, 1, 2, and 4 kHz thresholds) were highly correlated with mean behavioral response audiometry thresholds (R2 = 0.968, p < 0.001). ASSRs were highly and significantly correlated with behavioral response audiometry at 0.5, 1, 2, and 4 kHz (R2 = 0.845, 0.907, 0.929, and 0.859 respectively, p < 0.001). 87.5% and 90.7% ASSR thresholds were within a ± 10 dB range around their corresponding ABR and mean behavioral response audiometry thresholds. CONCLUSIONS: Narrow-band CE-Chirps allow a fast and reliable assessment of auditory thresholds in children, especially in the low-frequency range, by comparison with other stimuli.
Subject(s)
Acoustic Stimulation/methods , Audiometry, Evoked Response/methods , Auditory Threshold/physiology , Evoked Potentials, Auditory/physiology , Cohort Studies , Evoked Potentials, Auditory, Brain Stem/physiology , Feasibility Studies , Female , Humans , Infant , Infant, Newborn , Male , Prospective Studies , Reproducibility of ResultsABSTRACT
A major component of minimally invasive cochlear implantation is atraumatic scala tympani (ST) placement of the electrode array. This work reports on a semiautomatic planning paradigm that uses anatomical landmarks and cochlear surface models for cochleostomy target and insertion trajectory computation. The method was validated in a human whole head cadaver model (n = 10 ears). Cochleostomy targets were generated from an automated script and used for consecutive planning of a direct cochlear access (DCA) drill trajectory from the mastoid surface to the inner ear. An image-guided robotic system was used to perform both, DCA and cochleostomy drilling. Nine of 10 implanted specimens showed complete ST placement. One case of scala vestibuli insertion occurred due to a registration/drilling error of 0.79 mm. The presented approach indicates that a safe cochleostomy target and insertion trajectory can be planned using conventional clinical imaging modalities, which lack sufficient resolution to identify the basilar membrane.
Subject(s)
Cochlea/surgery , Cochlear Implantation/methods , Minimally Invasive Surgical Procedures/methods , Surgery, Computer-Assisted/methods , Basilar Membrane/pathology , Basilar Membrane/surgery , Cochlea/pathology , Humans , SoftwareABSTRACT
To evaluate the performance of the video head impulse test (VHIT) in assessing vestibular deficit in vestibular neuritis. Test validation study was conducted in Tertiary referral center. Twenty-nine patients, referred for vestibular neuritis between October 2009 and March 2012, were included. We recorded age, gender, values of caloric deficit (caloric testing), and deficits in semicircular function (VHIT) at initial presentation and at the follow-up visit (1-3 months). Multivariate linear regression analysis was performed to determine variables associated with values of caloric testing at the follow-up visit. Diagnostic values of VHIT were compared with caloric testing data using the receiver-operating characteristic (ROC) curve and subsequent statistical analysis. At the follow-up visit, complete recovery occurred in 31% of cases according to caloric evaluation, and VHIT normalized in 51.8%. Multivariate regression showed that a higher caloric deficit at the follow-up visit was associated with elevated age (p = 0.012) and high caloric deficit at initial presentation (p = 0.042). A lower caloric deficit was associated with normal VHIT results at the follow-up visit (p < 0.001). The ROC curve showed that specificity and sensitivity of VHIT were 100% when the caloric deficit was respectively lower than 40% or higher than 62.5%. At the caloric testing value of 30%, specificity was 100%, sensitivity 68.84%, positive predictive value 100% and negative predictive value 62.5%. VHIT is a fast, convenient and specific test to detect vestibular deficits in vestibular neuritis. However, VHIT lacks sensitivity by comparison with caloric testing, especially for moderate vestibular lesions.
Subject(s)
Head Impulse Test/methods , Vertigo/diagnosis , Vestibular Neuronitis/diagnosis , Adolescent , Adult , Age Factors , Aged , Caloric Tests/methods , Cohort Studies , Female , Humans , Linear Models , Male , Middle Aged , Multivariate Analysis , Prospective Studies , ROC Curve , Recovery of Function/physiology , Sensitivity and Specificity , Vertigo/etiology , Vertigo/physiopathology , Vestibular Neuronitis/complications , Vestibular Neuronitis/physiopathology , Video Recording/methods , Young AdultABSTRACT
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.
Subject(s)
Cochlear Implantation/instrumentation , Cochlear Implants , Correction of Hearing Impairment/instrumentation , Hearing Loss, Sensorineural/rehabilitation , Persons With Hearing Impairments/rehabilitation , Adult , Aged , Aged, 80 and over , Audiometry, Pure-Tone , Audiometry, Speech , Auditory Threshold , Europe , Female , Hearing , Hearing Loss, Sensorineural/diagnosis , Hearing Loss, Sensorineural/physiopathology , Hearing Loss, Sensorineural/psychology , Humans , Male , Middle Aged , Noise/adverse effects , Perceptual Masking , Persons With Hearing Impairments/psychology , Prospective Studies , Prosthesis Design , Quality of Life , Recognition, Psychology , Severity of Illness Index , Speech Intelligibility , Speech Perception , Time Factors , Young AdultABSTRACT
OBJECTIVES: We describe the various molecular and cellular pathways that lead to early and delayed loss of residual hearing after cochlear implantation. METHODS: We performed a systematic review using the Medline database with the key words cochlear implant, residual hearing, inflammation, apoptosis, and necrosis. RESULTS: The mechanisms underlying the loss of residual hearing after cochlear implantation are multiple. Early hearing loss may be provoked by the surgical access to the inner ear spaces and by trauma caused by insertion of the electrode array. After the initial trauma, an acute inflammatory response promotes elevated levels of cytokines and reactive oxygen species, which in turn promote sensory cell loss by apoptosis, necrosis, and necrosis-like programmed cell death. Treatments that counteract such an inflammatory reaction, production of reactive oxygen species, and apoptosis are effective at preventing hair cell degeneration. However, delayed hearing loss appears to be a consequence of chronic inflammation with development of fibrotic tissue. The mechanisms that lead to fibrosis are poorly understood, and standard antiinflammatory drugs are insufficient for preventing its development. CONCLUSIONS: Cochlear implantation is followed by an inflammatory response involving several pathways that lead to either short-term or long-term sensory hair cell degeneration. Future studies should focus on revealing the precise molecular mechanisms induced by cochlear implantation to allow the discovery of new targets for the effective prevention and treatment of loss of residual hearing.
Subject(s)
Cochlear Implants , Hearing Loss , Apoptosis , Audiometry, Pure-Tone , Auditory Threshold/physiology , Hearing , Hearing Loss/metabolism , Hearing Loss/pathology , Hearing Loss/surgery , HumansABSTRACT
Transtympanic promontory stimulation test (TPST) has been suggested to be a useful tool in predicting postoperative outcomes in patients at risk of poor auditory neuron functioning, especially after a long auditory deprivation. However, only sparse data are available on this topic. This study aimed at showing correlations between the auditory nerve dynamic range, evaluated by TPST, the electrical dynamic range of the cochlear implant and speech perception outcome. We evaluated 65 patients with postlingual hearing loss and no residual hearing, implanted with a Nucleus CI24 cochlear implant device for at least 2 years and with a minimum of 17 active electrodes. Using the TPST, we measured the threshold for auditory perception (T-level) and the maximum acceptable level of stimulation (M-level) at stimulation frequencies of 50, 100 and 200 Hz. General linear regression was performed to correlate 1/speech perception, evaluated using the PBK test 1 year after surgery, and 2/cochlear implant electrical dynamic range, with the age at time of implantation, the duration of auditory deprivation, the etiology of the deafness, the duration of cochlear implant use and auditory nerve dynamic range. Postoperative speech perception outcome correlated with etiology, duration of auditory deprivation and implant use, and TPST at 100 and 200 Hz. The dynamic range of the cochlear implant map correlated with duration of auditory deprivation, speech perception outcome at 6 months and TPST at 100 and 200 Hz. TPST test can be used to predict functional outcome after cochlear implant surgery in difficult cases.
Subject(s)
Cochlear Implants , Electric Stimulation , Hearing Loss/physiopathology , Hearing Loss/surgery , Speech Perception/physiology , Tympanic Membrane/physiology , Auditory Threshold/physiology , Cochlear Nerve/physiopathology , Electrodes , Female , Humans , Male , Middle Aged , Retrospective StudiesABSTRACT
OBJECTIVES: We compare the evolution of electrode impedance values (IVs) following either conventional cochlear implantation or implantation by the soft surgery (SS) technique. METHODS: We performed a retrospective chart review of 20 consecutive adult patients who underwent implantation with the Nucleus CA 24 device between 2004 and 2007. Five patients with preoperative residual hearing at the frequencies 256, 512, and 1,024 Hz underwent implantation by an SS cochlear implantation technique (SS group), and the 15 other patients underwent a conventional implantation technique (conventional cochleostomy [CC] group). The active electrodes were classified as distal (17 to 22), middle (10 to 16), or proximal (3 to 9) according to their position in relation to the tip of the electrode array. Their IVs were collected at 1, 3, 12, 24, and 36 months after implantation. Changes in auditory thresholds at 3 and 24 months were reported for patients in the SS group. RESULTS: The postoperative IVs of both the CC and SS groups decreased significantly between 1 and 3 months after implantation (p < 0.05) and then remained stable. The IVs after 12 months were significantly lower (p < 0.05) in the SS group than in the CC group. CONCLUSIONS: Patients who underwent the SS technique displayed lower long-term electrode IVs than did their counterparts in the CC group. If electrode IVs are indeed an indirect representation of cochlear fibrosis, the use of the SS technique in lieu of the CC technique could reduce fibrotic development.
Subject(s)
Cochlear Implantation/methods , Cochlear Implants , Hearing Loss/therapy , Adult , Aged , Auditory Threshold , Cicatrix/etiology , Cicatrix/prevention & control , Cochlear Implantation/adverse effects , Electric Impedance , Equipment Failure , Female , Humans , Male , Middle Aged , Retrospective Studies , Treatment Outcome , Young AdultABSTRACT
Loss of hair cells in the mammalian cochlea leads to permanent sensori-neural hearing loss. Hair cells degenerate and their places are taken by phalangeal scars formed by non-sensory supporting cells. Current data indicate that early postnatal post-mitotic supporting cells can proliferate and differentiate into hair cell-like cells in culture. In this study, we used GFAP and nestin promoter-GFP transgenic mice in combination with other stem cell markers to characterize supporting cell subtypes in the postnatal day-3 (P3) and adult organs of Corti with potential stem/progenitor cell phenotype. In P3 organ of Corti, we show GFAP-GFP signal in all the supporting cell subtypes while the nestin-GFP was restricted to the supporting cells in the inner hair cell area. At this stage, GFAP and selected stem/progenitor markers displayed overlapping expression pattern in the supporting cell population. In the adult, GFAP expression is down-regulated from the supporting cells in the outer hair cell area and nestin expression is down-regulated in the supporting cells of the inner hair cell area. Sox2 and Jagged1 expression is maintained in the mature supporting cells, while Abcg2 was down-regulated in these cells. In contrast, GFAP and Abcg2 expression was up-regulated in the inner sulcus limbal cells outside the mature organ of Corti's area. Using quantitative reverse transcription-PCR, we found a decrease in transcripts for Jagged1 and Sox2 in adult cochleae. Our findings suggest that the loss of regenerative capacity of the adult organ of Corti is related to down-regulation of stem/progenitor key-markers from the mature supporting cells.
Subject(s)
Cochlea/cytology , Gene Expression , Hair Cells, Auditory, Inner/cytology , Stem Cells/cytology , Animals , Biomarkers , Green Fluorescent Proteins/analysis , Green Fluorescent Proteins/genetics , Hair Cells, Auditory, Inner/metabolism , Intermediate Filament Proteins/analysis , Intermediate Filament Proteins/genetics , Mice , Mice, Transgenic , Nerve Tissue Proteins/analysis , Nerve Tissue Proteins/genetics , Nestin , Organ of Corti/cytologyABSTRACT
CONCLUSIONS: The results support bilateral sequential implantation for patients who are not completely satisfied after implantation of one side. OBJECTIVE: To evaluate the benefit of bilateral Vibrant Soundbridge middle ear implantation as compared with unilateral implantation in quiet and noisy environments. METHODS: This was a multicentric and retrospective study of 15 patients with symmetrical sensorineural hearing loss who were implanted sequentially in both ears. The performance of each subject was compared under three conditions: with the right implant activated, with the left implant activated, and with both implants activated. Audiometric tests were compared with self-assessment subjective evaluation by questionnaire. RESULTS: Both qualitative and quantitative assessments demonstrated improvement in speech intelligibility, especially in background noise, but also for low voice intensity in quiet.
Subject(s)
Ear, Middle/surgery , Hearing Aids , Hearing Loss, Bilateral/rehabilitation , Hearing Loss, Sensorineural/rehabilitation , Prosthesis Implantation , Social Environment , Speech Perception , Adult , Aged , Audiometry, Pure-Tone , Auditory Threshold , Female , Humans , Male , Middle Aged , Noise , Patient Satisfaction , Retrospective Studies , Speech Reception Threshold TestABSTRACT
OBJECTIVE: To investigate the educational and employment achievements of prelingually deaf children who undergo cochlear implantation. DESIGN: Prospective study. Data were examined within groups defined by current age and additional disabilities. Multivariate analyses were used to identify variables influencing grade failure and communication mode. SETTING: Tertiary referral center. PARTICIPANTS: One hundred prelingually deaf children who received cochlear implants before 6 years of age and who also had at least 4 years of follow-up. INTERVENTION: Interview of parents using a standardized questionnaire. MAIN OUTCOME MEASURES: The type of schooling, form of communication, employment status, age at which the child learned to read and write, number of grade failures, and educational support required. RESULTS: Mainstream schooling, regardless of educational level, was the standard experience for children without additional disabilities (16 of 24 [67%] in the 12- to 15-year age group to 20 of 24 [83%] in the 8- to 11-year age group). Four of 8 participants older than 18 years (50%) had a university-level education; the remainder had vocational training. Delayed reading and writing skills were experienced by 19 of 74 participants (26%) and, depending on the age group, 42% to 61% of participants (10 of 24 in the 8- to 11-year age group to 11 of 18 in the 16- to 18-year age group) had failed a grade. The number of grade failures was associated with communication mode at the time of the survey. Age at implantation, preoperative communication mode, and educational support influenced the final communication mode. In children with additional disabilities, the level of academic achievement and employment status varied. CONCLUSIONS: Despite significant differences in the grade failure rate between the children with cochlear implants and the general population, the participants in the present study ultimately achieved educational and employment levels similar to those of their normal-hearing peers. To minimize these delays and improve academic success in mainstream education, early oral education and early cochlear implantation are important.
Subject(s)
Child Development , Cochlear Implants , Deafness/therapy , Education, Special , Employment , Adolescent , Age Factors , Child , Child, Preschool , Cochlear Implantation , Deafness/complications , Deafness/psychology , Educational Status , Follow-Up Studies , Humans , Sign Language , Young AdultABSTRACT
OBJECTIVE: The purpose of this study was to examine prognostic factors of cochlear implantation and to evaluate the impact of early implantation on linguistic development in deaf children. STUDY DESIGN: Retrospective study. SETTING: Tertiary referral center. PATIENTS: Seventy-four prelingually deafened children implanted before the age of 5 years. INTERVENTION: Annual follow-up after cochlear implantation. MAIN OUTCOME MEASURES: Speech perception, intelligibility, and expressive and receptive language scores from age 3 to 8 years were globally compared between 4 subgroups of children. Significant differences were further explored by intergroup comparisons. Stepwise logistic linear regression was performed using the following variables: age at implantation, duration of cochlear implant (CI) use, preoperative hearing levels, age of hearing aid (HA) fitting, and age at time of the evaluation. Preoperative data were not available. RESULTS: Between group comparisons displayed significant differences according to age at implantation. Multivariate analysis demonstrated the positive impact of early implantation on receptive language. Moreover, duration of CI use and preoperative hearing levels were statistically correlated with performance on speech perception, intelligibility, and expressive and receptive language. Age of HA fitting was associated with speech intelligibility. CONCLUSION: Age at implantation, duration of CI, preoperative hearing levels, and age of HA fitting may each be useful in predicting linguistic success after cochlear implantation. Other factors such as preoperative linguistic development may also influence postoperative outcomes, but the lack of tests suitable for use with very young children makes such a hypothesis difficult to confirm.
Subject(s)
Cochlear Implantation/psychology , Deafness/psychology , Deafness/surgery , Language Development , Aging/psychology , Audiology , Child , Child, Preschool , Female , Follow-Up Studies , Humans , Linear Models , Male , Retrospective Studies , Speech , Speech Intelligibility/physiology , Speech Perception/physiologyABSTRACT
OBJECTIVES: Here, we evaluate the risks of amplified music for disc-jockeys (DJs) working in nightclubs. DESIGN: Sound level measurements were performed within the DJ mixing booths. A questionnaire was used to obtain exposure to noise and length of time in the profession. Audiograms and tinnitus pitch matching was also performed. RESULTS: The DJs' audiograms showed the expected noise-induced hearing loss at 6 KHz, but also low frequency losses at 125-500 Hz. Three quarters of them have tinnitus with a frequency corresponding to hearing loss. CONCLUSIONS: This study highlights the risk of amplified music on hearing and tinnitus.