Faculty Bibliography

OBJECTIVE: Perimodiolar electrode arrays were developed to improve stimulation of specific neural populations and to decrease power consumption. Postoperative radiographs suggest that some arrays are more tightly coiled than others. The purpose of this study was to evaluate whether the degree of modiolar coil correlates with electrical threshold and/or performance measures postimplantation with the Nucleus CI24RCS (Contour) device. STUDY DESIGN: Retrospective review. SETTING: Cochlear implant center and a tertiary care hospital. PATIENTS: Twenty-eight adult cochlear implant recipients with normal cochlear anatomy who underwent implantation with the Nucleus C124RCS perimodiolar electrode and are at least 1 year postimplantation. INTERVENTIONS: Therapeutic. MAIN OUTCOME MEASURES: Radiologic degree of perimodiolar electrode placement (determined by a computer algorithmic analysis) compared with electrical thresholds and standard speech perception outcome measures at 1 year postcochlear implantation. RESULTS: No significant correlations were found between the degree of modiolar coiling of the electrode array and electrical thresholds and speech perception outcome measures at 1 year postcochlear implantation. CONCLUSIONS: The degree of coiling of a modiolar hugging electrode array was not directly correlated with the level of electrical thresholds or postoperative speech perception outcome measures. Appearance of coil tightness on postoperative radiographs could reflect either differences in array placement or intrinsic variations in cochlear anatomy, and variations in speech perception performance can be influenced by other factors, including length of deafness

OBJECTIVE: To document oral language proficiency in a group of prelingually deaf bilingual children with a cochlear implant. DESIGN: Using a repeated-measures paradigm, oral language skills in the first and second language were evaluated at 2 yearly intervals after implantation. Language data were compared with normative data from children with normal hearing. SUBJECTS: Twelve deaf children between the ages of 20 months and 15 years who had received a cochlear implant before the age of 3 years. OUTCOME MEASURE: First-language skills were assessed using 1 of 2 standardized tests, either the Oral and Written Language Scales or the Reynell Developmental Language Scales, depending on the child's age. Second-language proficiency was assessed using the Student Oral Language Observation Matrix. RESULTS: Average standard scores in the first language fell solidly within the average range of normal-hearing peers. Second-language skills showed steady improvement from year 1 to year 2, along a continuum that reflected the amount and intensity of exposure of the child to the second language and the length of experience with the implant. CONCLUSION: A cochlear implant can make oral proficiency in more than 1 language possible for prelingually deaf children

Hearing aids and cochlear implants are two major hearing enhancement technologies but yet share little in research and development. The purpose of this study was to determine whether hearing aid directional microphones and noise reduction technologies could enhance cochlear implant users' speech understanding and ease of listening. Digital hearing aids serving as preprocessors were programmed to omni-directional microphone, directional microphone, and directional microphone plus noise reduction conditions. Three groups of subjects were tested with the hearing aid processed speech stimuli. Results indicated that hearing aids with directional microphones and noise reduction algorithms significantly enhanced speech understanding and listening comfort. (C) 2004 Acoustical Society of America

OBJECTIVE: The development of oral language in children with a cochlear implant is dependent on numerous factors. Although baseline achievements have been established, ceiling attainment levels have yet to be explored. One indicator of a higher capability level is the ability of children with implants to learn to communicate orally using a second language. The purpose of this research was to explore 1) the feasibility of children with cochlear implants developing oral fluency in a second language and 2) the factors that affect the development. STUDY DESIGN: Retrospective study of children fulfilling the criteria. SETTING: University medical center. PATIENTS: Eighteen profoundly hearing-impaired children who were reported to be bilingual. INTERVENTION: Cochlear implantation at age 5 or younger. MAIN OUTCOME MEASURES: The subjects were evaluated using standard speech perception and receptive and expressive language measures. RESULTS: The data revealed the ability of some pediatric cochlear implant recipients to develop competency in a second spoken language in addition to their primary language. Equally as important is the fact that the majority showed age-appropriate receptive and/or expressive language abilities in their primary language commensurate with normal-hearing children. CONCLUSION: High levels of achievement including the learning of a second spoken language are possible after implantation in the pediatric population. Variables include speech perception postimplantation, the linguistic environment, type of intervention, and educational placement

OBJECTIVE: Since 1987, when the use of multichannel cochlear implants was initiated in children, candidacy has expanded; many thousands of children have received these devices, and results have revealed a wide range of performance. However, few long-term studies exist on a large population of these children. There have been concerns expressed that cochlear implant function might degrade over time, that devices and electrodes might migrate and extrude in the growing child, or that there might even be a deleterious effect of long-term stimulation of the cochlear nerve. The purpose of this study was to explore the long-term effects of implantation as a function of performance over time, reimplantation, and educational factors. STUDY DESIGN AND SETTING: We studied 81 children who received implants at a major academic medical center and were followed for 5 to 13 years. RESULTS: Results revealed significant gains in speech perception, use of oral language, and ability to function in a mainstream environment. There was no decrease in performance over time and no significant incidence of device or electrode migration or extrusion, and device failure did not cause a deterioration in long-term outcome. CONCLUSIONS: Multichannel cochlear implants in children provide perception, linguistic, and educational advantages, which are not adversely affected by long-term electrical stimulation

OBJECTIVE: To determine the efficacy of cochlear implants with current processing strategies in children and adults with long-term congenital deafness, and to determine whether the growth of auditory perceptual skills in these patients is similar to the data reported for patients who have undergone implantation with earlier devices and coding strategies. STUDY DESIGN: A prospective study of children and adults fulfilling the study inclusion criteria. SETTING: University medical center. PATIENTS: Thirty-five congenitally deaf children who received implants after the age of 8 years and 14 congenitally deaf adults who received implants as adults participated in this study. Length of device use ranged from 6 months to 3 years. MAIN OUTCOME MEASURES: Open set phoneme, word recognition tests, and sentence recognition tests were administered in quiet and noise auditory only conditions preoperatively and postoperatively. Changes in test scores were examined by paired t tests, and differences between groups were compared by Student's t tests. Spearman correlation coefficients were calculated to identify associations between scores and subject characteristics. A two-sided alpha of less than 0.05 was considered statistically significant. RESULTS: The results indicated significant improvement in open set speech perception skills in the children after implantation; the adults demonstrated improved mean scores on both word and sentence recognition. A shorter length of deafness correlated with better postoperative performance, but all subjects continued to improve over time. The improvement in test scores was similar between the devices, and no significant differences were detected between the different processing strategies. CONCLUSION: Children and adults with long-term congenital deafness can obtain considerable open set speech understanding after implantation. Length of deafness (age at implantation), length of device use, and mode of communication contribute to outcome

OBJECTIVE: The study investigated the hypothesis that threshold and comfortable levels recorded from cochlear implant patients would reduce, and dynamic range increase, as distance of the electrode from the modiolar wall (radial distance) decreases. Two groups of cochlear implant patients participated; one group using the Nucleus' 24 Contour electrode array, and one group using the Nucleus standard straight (banded) array. The Nucleus 24 Contour array has been shown in temporal bone studies to lie closer to the modiolus than the banded array. The relationship of electrode impedance and radial distance is also investigated. DESIGN: The study, conducted at three centers, evaluated 21 patients using the Contour array, and 36 patients using the banded array. For each patient, threshold, comfortable levels and dynamic range were measured at four time points. Common ground electrode impedance was recorded clinically from each patient, at time intervals up to 12 wk. An estimate of the radial distance of the electrode from the modiolus was made by analysis of Cochlear view x-rays. RESULTS: Threshold and comfortable levels were significantly lower for the Nucleus 24 Contour array than for the banded array. However, dynamic range measurements did not show the predicted increase. In a majority of subjects, a significant correlation was found between the estimated radial distance of the electrode from the modiolus and the measured threshold and comfortable levels. This trend was not observed for dynamic range. The analysis indicates that other factors than radial distance are involved in the resultant psychophysical levels. Clinical impedance measures (common ground) were found to be significantly higher for the Contour array. However, the electrodes on the Contour array are half-rings, which are approximately only half the geometric size of the full rings as electrodes of the standard array. When the geometric electrode area in the two array designs are normalized, the trends in the electrode impedance behavior are similar. CONCLUSIONS: The results support the hypothesis that the relationship between the radial distance of the electrode and the psychophysical measures are influenced by patterns of fibrous tissue growth and individual patient differences, such as etiology and neural survival. Impedance measures for the Nucleus 24 Contour electrode array were higher than the banded electrode array, but this is primarily due to the reduction in electrode surface area. The different outcomes in impedance over time suggest differences in the relative contributions of the components of impedance with the two arrays

OBJECTIVES/HYPOTHESIS: The most common indication for cochlear reimplantation is device failure. Other, less frequent indications consist of 'upgrades' (e.g., single to multichannel), infection, and flap breakdown. Although the percentage of failures has decreased over time, an occasional patient requires reimplantation because of device malfunction. The varying designs of internal receiver/stimulators and electrode arrays mandate an examination of the nature and effects of reimplantation for the individual designs. The purpose of the current study was to investigate the reimplantation of several implant designs and to determine whether differences in surgical technique, anatomical findings, and postoperative performance exist. STUDY DESIGN: Retrospective chart review. METHODS: The subjects were 33 of 618 severely to profoundly deaf adults and children who had implantation at the New York University Medical Center (New York, NY) between February 1984 and December 2000. The subjects had previously had implantation with either a single-channel 3M/House (House Ear Institute, Los Angeles, CA) or 3M/Vienna (Technical University of Vienna, Vienna, Austria) device or with one of the multichannel Clarion (Advanced Bionics, Sylmar, CA), Ineraid (Smith & Nephew Richards, TN), or Nucleus (including the Contour) devices (Cochlear Corp., Englewood, CO) before reimplantation. RESULTS: Length of use before reimplantation ranged from 1 month to 13 years and included traumatic and atraumatic (electronic) failures, as well as device extrusion or infection. Results indicated that postoperative performance was either equal to or better than scores before failure. None of the devices explanted caused damage that precluded the implantation of the same or an upgraded device. These findings support the efficacy and safety of internal implant designs as related to the maintenance of a functional cochlea for the purpose of reimplantation. CONCLUSIONS: Cochlear reimplantation can be performed safely and without decrement to performance. The number of implanted electrodes at reinsertion were either the same or greater in all cases

The use of traditional electrocautery is prohibited in revision or replacement cochlear implant surgery because of the concern for end organ tissue damage. Additionally, electrical current spread to the malfunctioning device could interfere with an accurate cause-of-failure analysis. Clinical reports have confirmed the utility of the Shaw scalpel for dermatologic, ophthalmic, and head and neck surgery. The Shaw scalpel is a thermally activated cutting blade that provides a bloodless field through immediate capillary and small vessel hemostasis. Avoidance of wound and flap complications is of primary concern in cochlear implant surgery. The long-term wound healing compared favorably to that of other surgical cutting instruments in several experimental reports. We have routinely used the Shaw scalpel in revision cochlear implant surgery and in primary surgery whenever electrocautery was contraindicated. We have retrospectively evaluated 22 cases in which the Shaw scalpel was used for cochlear implant revision and primary surgery. The chart review included patient demographics, the indication for surgery, the contraindication for electrocautery, intraoperative surgical notes, the wound healing evaluation, the evaluation for alopecia, and postoperative speech understanding. No significant complications occurred intraoperatively, and the long-term wound healing results were no different from those obtained with conventional surgical techniques. The explanted devices were undamaged, and valuable diagnostic information could be obtained. All patients performed at or better than their preoperative levels on speech recognition testing. Our results indicate that the Shaw scalpel is a relatively safe, easy-to-use, and effective instrument