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PubMed2004

Being all ears: a systemic perspective on the role of the psychologist in cochlear implantation.

For those hearing-impaired individuals who do not derive any benefit from hearing amplification, cochlear implantation sometimes provides a useful alternative. Recently cochlear implant teams started to incorporate psychological services, mainly as a means to evaluate candidates as to their suitability to receive implants. This paper shows that cochlear implants can have serious and wide-ranging repercussions for the implantee and/or for the family, sometimes necessitating psychotherapeutic services. A case study is provided to illustrate the need for a much wider role for psychotherapeutic services and to also demonstrate how the adoption of a systems perspective can be of value to the therapeutic process.

Adaptation, Psychological↗

PubMed2005

Advantages of magnetic resonance imaging over computed tomography in preoperative evaluation of pediatric cochlear implant candidates.

OBJECTIVES: To compare magnetic resonance imaging (MRI) to high-resolution computed tomography (HRCT) in the preoperative evaluation of pediatric cochlear implant candidates. METHODS: The charts of pediatric cochlear implant candidates evaluated between July 1, 2000 and November 30, 2003 with an MRI scan of the inner ear were included in the study. Fifty-six patients were included. Associated HRCT scans were examined. Abnormalities of the cochlea, cochlear nerve, endolymphatic sac, endolymphatic duct, vestibule, and modiolus were noted. A pediatric neuroradiologist gave an opinion as to whether patients with anomalies seen with MRI but without associated HRCT would have been identified by HRCT. RESULTS: Of the 112 temporal bones imaged with MRI, the following abnormalities were encountered: 32% (36/112) had abnormalities of the cochlear turns, 30% (34/112) had abnormal signal in the modiolus, 23% (26/112) had abnormal vestibulae, 16% (18/112) had abnormal endolymphatic ducts, 15% (17/112) had abnormal endolymphatic sacs, 12% (13/112) had abnormalities of the cochlear nerves, 29% (17/56) had abnormalities of the brain. HRCT cannot directly evaluate the cochlear nerve. Available HRCT findings were combined with radiologic opinion and compared with MRI findings. The percentages of abnormalities identifiable by HRCT when compared with those seen with MRI are cochlea 42% (15/36), modiolus 35% (12/34), vestibulae 88% (23/26), endolymphatic duct 100% (18/18), and endolymphatic sac 6% (1/17). CONCLUSION: MRI is more sensitive and specific in diagnosing soft tissue abnormalities in the inner ear than HRCT in cochlear implant candidates (Fig. 4). Moreover, the abnormalities detected with MRI are more likely to influence the implantation process (e.g., asymmetric nerve aplasia, cochlear obstruction). (Figure is included in full-text article).

Child↗

PubMed2005

[The development of auditory capability for infants after cochlear implantation].

OBJECTIVE: The purpose of this study is to analyze the auditory capability of infants before and after cochlear implantation by using IT-MAIS questionnaire. METHOD: Eighty-six prelingually deaf patients participated in this study. They received a cochlear implant at the age of 1 to 3 yr. The audiologists who were trained for the research used the IT-MAIS questionnaire. Audiologists asked for the parents' answers face to face and recorded all the information about the patient's spontaneous auditory behavioural responses including vocalization, behaviour, spontaneous alerting to sound and deriving meaning from sound. The evaluation was performed before operation and 1 month, 3 months, 6 months, 1 year after switch-on. RESULT: The scores of question 1 were significantly different between pre-operation and 1, 3, 6, 12 months after switch-on (P = 0.000, 0.000, 0.000, 0.000). The scores of question 2 were significantly different between pre-operation and 6, 12 months after switch-on (P = 0.000, 0.000). The scores of question 3 were significantly different between pre-operation and 3, 6, 12 months after switch-on (P = 0.001, 0.000, 0.000). The scores of question 4 were significantly different between pre-operation and 3, 6, 12 months after switch-on (P = 0.002, 0.000, 0.000). The scores of question 5 were significantly different between pre-operation and 1, 3, 6, 12 months after switch-on (P = 0.046, 0.00, 0.000, 0.000, 0.000). The scores of question 6 were significantly different between pre-operation and 3, 6, 12 months after switch-on (P = 0.037, 0.000, 0.000). The scores of question 7 were significantly different between pre-operation and 3, 6, 12 months after switch-on ( P = 0.000, 0.000, 0.000). The scores of question 8 were significantly different between pre-operation and 6, 12 months after switch-on (P = 0.001, 0.001). The scores of question 9 were significantly different between pre-operation and 3, 6, 12 months after switch-on ( P = 0.023, 0.000, 0.000). The scores of question 10 were significantly different between pre-operation and 12 months after switch-on (P = 0.048). CONCLUSION: Most of the patients showed no consistent response to sound in everyday life before implantation. After cochlear implantation, a significant increase in auditory capability occurred. The children demonstrated faster development of vocalization behaviour and spontaneous alerting to sound than deriving meaning from sound.

Audiometry, Speech↗

PubMed2003

[Multi-channel cochlear implantation in patients with common cavity malformation].

OBJECTIVE: To report the multi-channel cochlear implantation in patients with Common cavity malformation, including surgeries, pre and postoperative hearing assessments as well as outcomes of speech recognition. METHOD: Multi-channel cochlear implantation surgeries have been performed in 6 cases with common cavity malformation in our hospital from May 1995 to May 2002. The transmastoid lateral semicircular canal approach was used in these cases. The postoperative outcomes of these cases are compared with 6 cases of non-malformed cochlea as a control group. RESULT: Among the 6 cases, All 32 electrodes were inserted in 3 cases, 28 electrodes in 1 cases, 26 electrodes in 1 cases, 22 electrodes in 1 cases. The intra and postoperative complications of the surgeries have no significant difference compared with the surgeries of normal cochlea. The intraoperative "Ozze" occurred in 2 cases, the small CSF flowing occurred in 3 cases and no CSF flowing occurred in 1 case. Postoperative threshold in sound field were 30-40 dB recovery for all cases, and similar to the normal cochlea cases. Most of them received the similar hearing and speech recovery, compared with the result of non-malformed group. Only a few had a higher hearing threshold. The remote effect will be evaluated by long-term follow-up. CONCLUSION: Multi-channel cochlear implantation could be performed in the cases with common cavity malformation, but preoperative hearing assessments and proper images should be done.

Child↗

PubMed2003

[Electrically evoked compound action potential thresholds of pediatric cochlear implant recipients and its clinical application].

OBJECTIVE: To investigate the possibility of using pediatric cochlear implant mapping protocol, to estimate the psychophysical levels based on the electrically evoked compound action potential (ECAP) threshold measured with the neural response telemetry (NRT) capabilities of cochlear corporation's CI24M device. METHODS: ECAP amplitude growth functions were regressed via NRT 3.0 software to determine ECAP threshold. 6 pediatric cochlear implant recipients' ECAP thresholds 1, 2 and 3 months after surgery were compared, meanwhile, intraoperative and postoperative ECAP thresholds in 7 pediatric recipients were compared. RESULTS: The ECAP amplitude growth functions were not linear when ECAP was close to threshold or saturation. There were no significant difference among the ECAP thresholds 1, 2 and 3 months after surgery. The average intraoperative ECAP threshold of 22 electrodes was 15 CL greater than postoperative threshold. It showed high relationship between them (R2 = 0.9154). CONCLUSION: ECAP threshold should be determined by regression of data from linear part of amplitude growth function. Only one NRT trial should be assessed when mapping protocol based on ECAP threshold to estimate pediatric map parameter. The intraoperative ECAP threshold can act as C-level at the initial mapping. Key words cochlear implant, electrically evoked compound action potential, mapping.

Action Potentials↗

PubMedDate not supplied

Audiological results with two single channel cochlear implants.

We tested six patients with single channel cochlear implants on several tests from the Minimal Auditory Capabilities battery and the Iowa Cochlear Implant Tests. All patients were able to discriminate some everyday sounds and to identify the number of syllables in the words presented. Five patients were able to identify speaker sex reliably. Surprisingly, some patients had difficulty discriminating between a modulated noise and a voice or between a question and a statement or identifying the accented word in a sentence. On several audiovisual tests, an improvement was observed for the sound plus vision condition compared to the vision only condition. This was particularly true for sentence tests, but was not uniform across patients or across tests.

Adult↗

PubMed2006

Cochlear implantation in postirradiated ears: outcomes and challenges.

OBJECTIVES: Radiotherapy to head and neck tumors can potentially damage the auditory pathways. This has relevance in cochlear implants and there is a need for clinical studies to confirm the feasibility of cochlear implantation in these patients. METHODS: The records of all patients who had received cochlear implants at our institution were reviewed in this retrospective study and those who had prior irradiation for head and neck tumors were further studied. Case controls consisted of comparable cochlear implant recipients who did not have prior radiotherapy. RESULTS: Four of 230 patients met the criteria for further study. They had received radiotherapy for nasopharyngeal carcinoma 11 to 28 years ago and the postimplant follow-up period ranged from 9 to 46 months. The implanted ear of each patient had favorable preoperative promontory stimulation results. Postimplant, all patients were satisfied with their hearing outcomes and the improvement in speech discrimination scores was comparable to the controls. These cases also illustrated specific clinical concerns, including 1) radiation-induced endocrine dysfunction was common and, if overlooked, could result in increased anesthetic risks, and 2) irreversible eustachian tube dysfunction led to chronic middle ear problems, which complicated surgery; the use of modified surgical techniques overcame these difficulties. CONCLUSIONS: Deafened postirradiated patients with nasopharyngeal carcinoma were able to achieve good postimplant hearing outcomes comparable to those of nonirradiated patients. Should cochlear implantation be indicated in patients who have had prior radiation to the head and neck, specific preoperative, intraoperative, and postoperative issues have to be addressed.

Aged↗

PubMed1999

Amplitude mapping and phoneme recognition in cochlear implant listeners.

OBJECTIVE: Speech and other environmental sounds must be compressed to accommodate the small electric dynamic range in cochlear implant listeners. The objective of this paper is to study whether and how amplitude compression and dynamic range reduction affect phoneme recognition in quiet and in noise for cochlear implant listeners. DESIGN: Four implant listeners using the Nucleus-22 SPEAK speech processor participated in this study. The amount of compression was varied by manipulating the Q-value in the SPEAK processor. The size of the dynamic range was systematically reduced by increasing the threshold level and decreasing the comfortable level in the processor. Both female- and male-talker vowel and consonant materials were used to evaluate speech recognition performance in quiet and in noise. Speech-spectrum-shaped noise was mixed with the speech signal and presented continuously to the speech processor through a direct electric connection. Signal to noise ratios were changed over a 30 to 40 dB range, within which phoneme recognition increased from chance to asymptotic performance. Phoneme recognition scores were obtained as the number of active electrodes was reduced from 20 to 10 to 4. For purposes of comparison, phoneme recognition data also were collected in four normal-hearing listeners under comparable laboratory conditions. RESULTS: In both quiet and noise, the amount of amplitude compression did not significantly affect phoneme recognition. The reduction of dynamic range marginally affected phoneme recognition in quiet, but significantly degraded phoneme recognition in noise. Generally, the 20- and 10-electrode processors produced similar performance, whereas the 4-electrode processor produced significantly poorer performance. Compared with normal-hearing listeners, cochlear-implant listeners required higher signal to noise ratios to achieve comparable recognition performance and produced significantly lower recognition scores at the same signal to noise ratios. CONCLUSIONS: The amount of amplitude compression does not significantly affect phoneme recognition, whereas reducing dynamic range significantly lowers phoneme recognition, particularly in noise and for vowels. Because the SPEAK processor extracts mostly spectral peaks, the present conclusions may not be applied to other types of processors extracting temporal envelope cues. The present results also suggest that more than four electrodes are required to optimize speech recognition in multiple-talker and noise conditions. A significant performance gap in speech recognition still remains between cochlear implant and normal-hearing listeners at the same signal to noise ratios. Improved cochlear implant designs and fitting procedures are required to narrow and, hopefully, close this performance gap.

Adult↗

PubMed2000

[91 dB hearing loss--the threshold for cochlear implant?]].

BACKGROUND AND OBJECTIVE: Recent indications for cochlear implant in children are bilateral total cochlear deafness and an age of 2 or more. Reports on successful implantations in adults with residual hearing pose the question of whether this indication might be expanded to children with residual hearing. PATIENTS/METHODS: In a retrospective analysis of 106 hearing-impaired children with binaural amplification, we were able to ask parents in 90 cases about their children's education. The pure-tone average of the frequencies of 1-4 kHz was correlated to education. RESULTS: The results showed that all children except one with a pure-tone average of < or = 90 dB could successfully attend regular school or kindergarten. However, those with a pure-tone average of > or = 91 dB had to be educated in special units for children with impaired hearing. CONCLUSIONS: Our results indicate that amplification in children with profound hearing loss (pure-tone average > or = 91 dB) is not sufficiently effective to enable them to attend regular schools or kindergarten. We conclude that the only chance to integrate these children into the world of hearing might be cochlear implantation.

Adult↗

PubMed1991

[Cochlear implants in children: acquisitions and controversies].

This paper analyzes the main difficulties encountered in cochlear implants in children. Neurophysiological data indicate that cochlear implants should be put during the first 3-4 years of life. The principal controversies concern: the indications of cochlear implants, the type of implant (mono or multichannel), surgical problems, problems of implant set-up, strategy of rehabilitation.

Age Factors↗

PubMed2005

Surgical considerations in cochlear implantation in children and adults: a review of 342 cases in Vienna.

CONCLUSIONS: Our data represent the experience of the largest cochlear implant program in Austria. In conclusion, cochlear implantation is a safe procedure, associated with a low rate of intra- and postoperative complications. Nevertheless, patients should be informed about possible problems and especially about the risk of a reoperation due to device failure. OBJECTIVES: To evaluate the cause of deafness, the intraoperative findings and the complication rate for all cochlear implant operations performed consecutively between 1994 and 2003 at Vienna General Hospital. MATERIAL AND METHODS: Including all surgeries for bilateral implantation and revision, a series of 342 operations performed on 164 adults (age range 14.5-81 years; mean age 50.79 years) and 128 children (age range 0.75-14 years; mean age 5.00 years) was retrospectively analyzed. RESULTS: The etiology of deafness was predominantly congenital or progressive (66.89%). The routine mastoidectomy approach was chosen in 300 patients (87.72%) and the suprameatal approach in 42 (12.28%). Intraoperatively, 4 children (2.53%) had a cerebrospinal fluid fistula and 35 patients (10.23%) showed cochlear ossification. Three adults (1.63%) and two children (1.27%) had facial nerves with an aberrant course. The overall complication rate was 12.2%, the rate of major complications was 4.97% and the rate of minor complications was 4.09%. There were no cases of either postoperative meningitis or facial nerve palsy. Both flap necrosis and electrode dislocation occurred in one adult patient (0.54%), but in none of the children. Formation of cholesteatoma was found in one adult (0.54%) and one child (0.63%). The rate of device failure was 7.07% for adults and 13.92% for children.

Adolescent↗

PubMed1996

Successful revision of failed cochlear implants in severe labyrinthitis ossificans.

Labyrinthitis ossificans may complicate the insertion of a multichannel cochlear implant in patients deafened after meningitis. Two children who initially underwent partial insertion of a 22-channel cochlear implant because of severe cochlear ossification required revision surgery after several months of unsuccessful device use. At the time of revision, resection of the car canal, tympanic membrane, malleus, and incus provided access to the lateral wall of the cochlea, permitting extensive drilling of the basal turn and a circumodiolar placement of the electrode. Functional integrity of the electronic components of the original device was documented intraoperatively, avoiding the expense of a new receiver-stimulator. Complete insertion of the active electrodes was accomplished in both cases, and electrophysiologic responsiveness to the implant was documented using intraoperative electrically evoked auditory brainstem response recordings. Postoperative performance has been similar to that of cochlear implant patients with nonossified ears. Experience with these two cases suggests that efforts to optimize electrode insertion at the original surgical procedure are appropriate and may help to avoid the disappointment of an unsuccessful cochlear implant.

Child↗

PubMed2006

Complication rate of minimally invasive cochlear implantation.

OBJECTIVES: To assess the complication rate of minimally invasive cochlear implantation (MICI). STUDY DESIGN AND SETTING: Data for this study were obtained via a retrospective analysis of records at the Ear Medical Group, San Antonio, TX, after IRB approval at the University of Texas Health Science Center at San Antonio. The surgical complications of MICI were recorded in a spreadsheet format; 176 patients were included in the study. RESULTS: A total of 22 (12.5%) complications were noted in the study. There were 0 life-threatening, 7 major, and 15 minor complications. Of the 7 major complications, 3 were device failures, 2 developed delayed mastoiditis, 1 required receiver/stimulator repositioning, and 1 involved facial paralysis. CONCLUSIONS: MICI is as safe as standard cochlear implantation (SCI) and affords with it other benefits. Eliminating the scalp flap avoids devascularization and minimizes the opportunity of flap infection or necrosis. Complications not related to the flap are similar to SCI. EBM RATING: C-4.

Adolescent↗

PubMed1996

Differences in children's sound production when speaking with a cochlear implant turned on and turned off.

Twenty children who have worn a Cochlear Corporation cochlear implant for an average of 33.6 months participated in a device-on/off experiment. They spoke 14 monosyllabic words three times each after having not worn their cochlear implant speech processors for several hours. They then spoke the same speech sample again with their cochlear implants turned on. The utterances were phonetically transcribed by speech-language pathologists. On average, no difference between speaking conditions on indices of vowel height, vowel place, initial consonant place, initial consonant voicing, or final consonant voicing was found. Comparisons based on a narrow transcription of the speech samples revealed no difference between the two speaking conditions. Children who were more intelligible were no more likely to show a degradation in their speech production in the device-off condition than children who were less intelligible. In the device-on condition, children sometimes nasalized their vowels and inappropriately aspirated their consonants. Their tendency to nasalize vowels and aspirate initial consonants might reflect an attempt to increase proprioceptive feedback, which would provide them with a greater awareness of their speaking behavior.

Child↗

PubMed2002

Cochlear implantation in prelingually deafened children with residual hearing.

OBJECTIVE: The purpose of this study was to examine the speech perception skills of prelingually deafened French children with preoperative residual hearing who received multichannel cochlear implants. DESIGN: The design of the study incorporated a within-subject, repeated measures design for assessing speech perception skills. SETTING: Montpellier, Toulouse and Lyon Pediatric Cochlear Implant Centers. SUBJECTS: Seven prelingually deafened children demonstrating marginal benefit from conventional amplification prior to implantation with a Nucleus multichannel cochlear implant, served as subjects for the speech perception assessment (a speech recognition score less than 30% defines marginal benefit from acoustic amplification on open set materials). The mean age at implantation was 7 years, 9 months. OUTCOME MEASURES: Speech perception skills were assessed using open set materials and the MUSS and MAIS questionnaires. RESULTS: Open-set speech recognition averaged 21.4% before implantation, and 83.6% after 1 year's cochlear implant experience. All children demonstrated an open-set score over 60% after 12 months of CI use. MAIS test scores averaged 18.1/40 before implantation and 35.1/40 after 9 months of CI use. MUSS test scores averaged 24.4/40 before implantation and 34.1/40 after 9 months of CI use. CONCLUSIONS: Cochlear implantation should be considered for prelingually hearing impaired children demonstrating marginal benefit from hearing aids, with a speech recognition score less than 30% on open set materials, in order to improve their speech discrimination skills.

Audiometry↗

PubMed1992

Young cochlear implant users' response to delayed auditory feedback.

This investigation determined whether the signal provided by the Cochlear Corporation Nucleus cochlear implant can convey enough speech information to induce a response to delayed auditory feedback (DAF), and whether prelingually deafened children who received a cochlear implant relatively late in their speech development are susceptible. Ten children with the Nucleus cochlear implant spoke simple phrases, first without and then with DAF. Three prelingually deafened subjects and the only two postlingually deafened subjects demonstrated longer phrase durations when speaking with DAF than without it. Two of the prelingually deafened subjects who demonstrated a response received their cochlear implants at the age of 5 years.

Attention↗

PubMed2004

Speech recognition in noise for cochlear implant listeners: benefits of residual acoustic hearing.

The purpose of this study was to explore the potential advantages, both theoretical and applied, of preserving low-frequency acoustic hearing in cochlear implant patients. Several hypotheses are presented that predict that residual low-frequency acoustic hearing along with electric stimulation for high frequencies will provide an advantage over traditional long-electrode cochlear implants for the recognition of speech in competing backgrounds. A simulation experiment in normal-hearing subjects demonstrated a clear advantage for preserving low-frequency residual acoustic hearing for speech recognition in a background of other talkers, but not in steady noise. Three subjects with an implanted "short-electrode" cochlear implant and preserved low-frequency acoustic hearing were also tested on speech recognition in the same competing backgrounds and compared to a larger group of traditional cochlear implant users. Each of the three short-electrode subjects performed better than any of the traditional long-electrode implant subjects for speech recognition in a background of other talkers, but not in steady noise, in general agreement with the simulation studies. When compared to a subgroup of traditional implant users matched according to speech recognition ability in quiet, the short-electrode patients showed a 9-dB advantage in the multitalker background. These experiments provide strong preliminary support for retaining residual low-frequency acoustic hearing in cochlear implant patients. The results are consistent with the idea that better perception of voice pitch, which can aid in separating voices in a background of other talkers, was responsible for this advantage.

Adult↗

PubMed1999

Central nervous system metabolic activity after cochlear implantation in the feline neonatal model.

OBJECTIVE: To determine the effects of deafening and cochlear implant stimulation on central nervous system (CNS) metabolic activity in the feline neonate model. BACKGROUND: Deafening of fetal animals has been shown to result in acute, profound depression of CNS glucose metabolism, in both auditory structures and the cerebral hemispheres. Preliminary studies have suggested that electrical stimulation of the auditory system may increase central nervous metabolic activity after deafening. The purpose of this study was to investigate this possibility. METHODS: This was a prospective, randomized, blinded, and controlled animal study of 13 random-source newborn kittens. It was set in an animal research facility for otologic disorders. OUTCOME: Deoxyglucose metabolism (assessed with autoradiograph densitometry) of brain cross-sections of normal, deafened, and deafened and cochlear-implanted animals after 6 weeks of auditory stimulation or deprivation. RESULTS: Chronic deafening did not result in a profound reduction in CNS metabolic activity. Cochlear implantation and electrical stimulation did not significantly raise the level of CNS metabolic activity within either auditory pathways or the cerebral hemispheres. CONCLUSIONS: Deafening is not associated with significant chronic reduction in CNS metabolic activity. Other parameters of CNS activity and maturation may be necessary to assess the effects of cochlear implantation and stimulation in animal models.

Animals↗