Cochlear implant soft failures consensus development conference statement.
Explore the source record for details and available documents.
Cochlear Implants↗
Biomedical subjects
T J Balkany
Publications and source records attributed to T J Balkany.
Caspases, the enemy within, and their role in oxidative stress-induced apoptosis of inner ear sensory cells.
This review covers the general roles of members of the cysteine protease family of caspases in the process of apoptosis (programmed cell death) looking at their participation in both the "extrinsic" cell death receptor and the "intrinsic" mitochondrial cell death pathways. It defines the difference between initiator and effector caspases and shows the progression of caspase activations that ends up in the apoptotic cell death and elimination of a damaged cell. The review then presents what is currently know about the participation of caspases in the programmed cell death of inner ear sensory cells during the process of normal development and maturation of the inner ear and their importance in this process as illustrated by the results of caspase-3 gene knockout experiments. The participation of specific caspases and the sequence of their activation in the elimination (apoptosis) of damaged sensory cells from adult inner ears after an injury that generates oxidative stress are reviewed. Both the possibility and the potential efficacy of caspase inhibition with a broad-spectrum pancaspase inhibitor as an interventional therapy to treat and rescue oxidative stress-damaged inner ear sensory cells from apoptosis are presented and discussed.
Adult↗
Cochlear implants in children.
Cochlear implants are electronic prostheses that provide a high quality sense of hearing to severely and profoundly deaf children and adults. As improvements in surgical technique and device performance have occurred, indications for implantation have expanded.
Child↗
Octreotide scintigraphy for the detection of paragangliomas.
Paragangliomas are neuroendocrine tumors located primarily in the head and neck region, but they can also occur at other sites. Confirming the preoperative diagnosis and detecting synchronous tumors may be difficult in some patients. Octreotide is a somatostatin analog that, when coupled to a radioisotope, produces a scintigraphic image of tumors expressing somatostatin type 2 receptors. Paragangliomas, like many neuroendocrine tumors, have been found to have a high density of somatostatin type 2 receptors on the cell surface. This study compared the results of preoperative octreotide scintigraphy with the histopathology in 21 patients who underwent surgery for presumed head and neck paragangliomas. Octreotide scan findings were positive in 16 patients with paragangliomas and negative in 3 patients with other pathology. One false-positive and 1 false-negative result were obtained. Thus, this test had an accuracy of 90%, a sensitivity of 94%, and a specificity of 75%. Previously unidentified synchronous tumors were identified in 5 patients. On the basis of this series of patients, octreotide scintigraphy appears to be a reliable test to detect paragangliomas and may be quite helpful in preoperative planning.
Female↗
Novel intracochlear electrode positioner: effects on electrode position.
Spiral ganglion cells, located in the cochlear modiolus, are widely thought to be the neural elements stimulated by cochlear implants (CIs). Positioning CI electrodes adjacent to the modiolus may allow delivery of more focused, discrete fields of electrical stimulation, reducing both current requirements and the channel interaction associated with simultaneous stimulation. In order to provide greater consistency in positioning CI electrodes against the modiolus, Advanced Bionics Corporation has designed a silicone intracochlear positioner that is inserted alongside the electrode. Placed against the outer wall of the scala tympani, it directs the electrode array toward the modiolus. Five fresh-frozen temporal bones were studied to validate enhanced electrode placement. Electrode position was documented with image-enhanced digital fluoroscopy, and the distance to the modiolus was measured with computer-assisted morphometrics. The electrode positioner was highly effective in positioning the electrodes closer to the modiolus (p < .001).
Adult↗
Borderline pediatric cochlear implant candidates: preoperative and postoperative results.
Explore the source record for details and available documents.
Adolescent↗
Changes in stimulation levels over time in nucleus 22 cochlear implant users.
The purpose of this study was to evaluate changes that occur over time in the electrical stimulation levels of cochlear implant users. A retrospective review of program summaries for 26 postlingually deafened adult Nucleus cochlear implant users was completed. Program summaries were used to assess changes in electrical stimulation at threshold (T) and maximum comfort (C) levels. Comparisons were made at intervals including the subject's initial stimulation and 2-week, 3-month, 6-month, 1-year, and most recent programming sessions. Five patients had 5 years or more of implant use; 8 patients had 3 to 5 years or more of implant use; and the remainder had been using their implant for 2 to 3 years. No patient with less than 2 years of implant use was included. Results indicated that changes in stimulation levels occur gradually over time. Although the changes in stimulation levels from one programming session to the next were not significant, the changes in current requirements for both T and C levels were found to be significant when we compared the 6-month and most recent programming intervals.
Adult↗
Comparison of language ability in children with cochlear implants placed in oral and total communication educational settings.
Explore the source record for details and available documents.
Child, Preschool↗
Speech perception results in children with cochlear implants: contributing factors.
Speech perception test results were obtained from a group of 40 pediatric cochlear implant users. Half of the children participated in oral-only habilitation programs, which included both traditional oral and auditory-verbal approaches, and half participated in programs that used a combination of oral and manual communication referred to as total communication (TC). Analysis of the scores showed that children enrolled in oral-only habilitation programs scored significantly higher on the speech perception measures than did children who were enrolled in total communication based programs. These results were inconsistent with those of other reports, which suggested that communication methods had little effect on implant outcomes. To further examine the reasons for the differences in performance, we analyzed 7 additional factors, including length of implant use, age at surgery, device type, socioeconomic status, bilingualism, school setting, and participation in private therapy, which may affect implant performance. Multiple-regression analysis again showed communication mode to be the factor most highly correlated with speech perception abilities among this group of children.
Adolescent↗
Effects of cis-platinum chemotherapy on otoacoustic emissions: the development of an objective screening protocol. Third place--Resident Clinical Science Award 1998.
To develop an objective, fast, and simply performed screening protocol for cis -platinum (CP) ototoxicity, we compared the efficacy of screening with distortion-product otoacoustic emissions (DPOAEs) with the outcome of both conventional and ultra-high-frequency (UHF) audiometry. Baseline audiometric and DPOAE testing was performed in 66 patients, 33 of whom met criteria for inclusion in the final database. Comparisons were made between baseline measurements and those recorded before subsequent CP infusions. Outcomes were analyzed clinically and with paired repeated-measures analysis of variance. Results indicated that DPOAEs and UHF were better measures than conventional audiometry. Further, DPOAEs may be better suited for screening older patients receiving CP chemotherapy because DPOAEs are as sensitive as UHF and are present in a greater number of these patients. Screening with DPOAEs may be enhanced by testing only in the 3- to 5.2-kHz range, thus decreasing testing time. Higher time averages to increase the signal-to-noise ratio and use of this narrower bandwidth might also allow for accurate bedside testing.
Adult↗
Cochlear reimplantation.
OBJECTIVE: A small number of multichannel cochlear implant (CI) recipients require reimplantation. This study describes the causes of failure, surgical technique, and hearing outcomes in a consecutive series of 16 patients undergoing reimplantation of multichannel devices. We hypothesize that reimplantation is safe and that hearing results are at least as good as those measured following primary implantation. STUDY DESIGN: Retrospective analysis of consecutive clinical series. METHODS: Chart analysis of 191 consecutive CI operations performed at the University of Miami Ear Institute between 1990 and 1997 revealed 16 patients who received a second multichannel device. All but one had a minimum follow-up of 1 year after reimplantation. Ten of these patients had initial implantation performed by us, and six were initially operated on elsewhere. Main outcomes of the initial procedure were compared with those of the reimplantation, including electrode insertion length, number of channels programmed, and audiometric results. In addition, cause of failure and relevant surgical findings at the second procedure are described. RESULTS: There were no surgical complications after reimplantation surgery. Device failure was the most frequent cause for reimplantation. Time between initial implantation and failure ranged from 0 to 46 months (mean, 22.4 mo; median, 23 mo). Common intraoperative findings include mastoid fibrosis, bone growth at the cochleostomy, and skin flap breakdown. Following reimplantation, mean length of insertion, number of channels actively programmed, and speech recognition scores were at least as good as findings before initial implant failure. CONCLUSION: CI reimplantation is safe and effective.
Adolescent↗
Surgical technique for the CLARION cochlear implant.
This paper describes a technique for implantation of the CLARION Multi-Strategy Cochlear Implant based upon the authors' surgical experience with the device. Although much of the procedure is similar to many commonly performed otologic operations, including implantation of other cochlear prostheses, several device-specific modifications are highlighted. Those modifications include a substantial bony seat, facial recess, and cochleostomy, and the use of an electrode insertion tool.
Cochlea↗
Using the CLARION cochlear implant in cochlear ossification.
This paper is a retrospective review of 5 patients with various degrees of cochlear ossification who were implanted with the CLARION Multi-Strategy Cochlear Implant. Preoperative computed tomography scans, intraoperative findings, surgical technique, and hearing outcomes are discussed in a case report format. Full implantation was achieved in all cases by a systematic approach that included drill-through of proximal obstruction (2 cases), scala vestibuli insertion (2 cases), and complete drill-out (1 case). The only complication was delayed wound healing in a patient with sickle cell disease, chronic active hepatitis, and steroid dependency on antimetabolite therapy. Early results show that the 4 patients with at least 3 months of experience have a mean open-set sentence recognition score of 55% and a mean open-set word recognition score of 24%. The conclusion is that implantation of the Clarion device in ossified cochleas can be successful in all degrees of ossification and can provide significant hearing benefit.
Adolescent↗
Using electrically evoked auditory reflex thresholds to fit the CLARION cochlear implant.
This paper describes a method for measuring electrically elicited auditory reflex thresholds (EARTs) in young children who use the CLARION Multi-Strategy Cochlear Implant. The EART is an objective measure that can guide the fitting of a cochlear implant in individuals who are unable to perform behavioral tasks required to program the device. Reflexes were obtained in 11 of 17 pediatric Clarion users. The EART current level indicated a point at which an auditory percept was present and the sound was loud, but not uncomfortable. The EART then was used as a basis for conditioning behavioral responses, and as a guideline for setting most comfortable loudness levels.
Cochlear Implantation↗
Speech recognition after implantation of the ossified cochlea.
OBJECTIVE: Insertion of complex, multichannel cochlear implant (CI) electrode arrays into ossified cochleas is now performed routinely. This study describes the hearing results obtained in a consecutive series of 21 patients with obstructed cochleas and compares these results to those in patients with open cochleas. The purpose of this study was to determine whether patients with ossification have speech perception results that are inferior to those of patients with no evidence of cochlear bone formation. STUDY DESIGN: Retrospective analysis of consecutive clinical series. METHODS: CI database review of 191 CI procedures at the University of Miami Ear Institute between 1990 and 1997 showed that 24 (13%) procedures were performed on patients with ossified cochleas. Open-set speech recognition scores obtained on the 11 pediatric and 7 adult English-speaking patients are compared to scores of 51 adult and 61 pediatric English-speaking CI patients with open scala. RESULTS: Results of open-set speech recognition measures in adults and children with ossified cochleas were not significantly different from those of the reference groups. CONCLUSION: Speech recognition results of patients with ossified cochleas are essentially equal to those of patients with open cochleas. Degree of obstruction appears to have less effect on outcome than other factors such as duration of profound deafness or communication methodology in children among this group.
Adolescent↗
Visual-vestibular habituation and balance training for motion sickness.
BACKGROUND AND PURPOSE: This case report describes physical therapy for motion sickness in a 34-year-old woman. The purpose of the report is twofold: (1) to provide an overview of the literature regarding motion sickness syndrome, causal factors, and rationale for treatment and (2) to describe the evaluation and treatment of a patient with motion sickness. CASE DESCRIPTION AND OUTCOMES: The patient initially had moderate to severe visually induced motion sickness, which affected her functional abilities and prevented her from working. Following 10 weeks of a primarily home-based program of visual-vestibular habituation and balance training, her symptoms were alleviated and she could resume all work-related activities. DISCUSSION: Although motion sickness affects nearly one third of all people who travel by land, sea, or air, little documentation exists regarding prevention or management.
Adult↗
Distortion-product otoacoustic emission monitoring of cochlear blood flow.
Distortion-product otoacoustic emissions (DPOAEs) have been shown to be ideally sensitive to interruptions of the cochlear blood flow. However, a 15- to 30-second latency typically occurs between cessation of circulation and measurable DPOAE level changes. DPOAEs can also be characterized by phase measures. The aim of the present study was to determine in 10 rabbits the effects on DPOAE phase of repetitively compressing the internal auditory artery. In contrast to the delays measured by DPOAE level, phase changes were detected 1 to 5 seconds after internal auditory artery compression. These data suggest that the essentially "real time" monitoring of cochlear function with DPOAE phase can be used to ensure hearing preservation during surgery involving the porus acousticus and skull base.
Acoustic Stimulation↗
Electrical middle ear muscle reflex: use in cochlear implant programming.
Programming of multichannel cochlear implants (CIs) requires subjective responses to a series of sophisticated psychophysical percepts. It is often difficult for young prelinguistically deaf children to provide adequate responses for device fitting. This is especially true in setting levels of maximum comfortable loudness, whereby failure to indicate growth of loudness may result in elevation of stimulus levels to the threshold of pain. The acoustic or stapedial muscle reflex has been used previously to provide objective confirmation of acoustic stimulation, and there have been attempts to use the reflex in hearing aid fitting. It has also been suggested that electrically elicited middle ear muscle reflexes (eMEMR) may have applicability in confirming and quantifying electrical stimulation through a CI. To assess the relationship between eMEMR characteristics and levels of loudness perception with CIs, determine reliability of the response, and investigate potential use of eMEMR in CI programming, 25 postlinguistically deafened adult CI users were evaluated. Reflexes have also been attempted on 40 children, with responses present in 31 (71%). Comfort levels predicted by eMEMR were highly correlated with those obtained through subjective judgments in the adult subjects. The eMEMR provides an objective, accurate, and rapid method of estimating maximum comfortable loudness levels, which may be useful in the initial programming of young implant recipients.
Acoustic Stimulation↗