Quality of Life after Sequential Bilateral Cochlear Implantation.

Objective Assess psychometric properties of the Comprehensive Cochlear Implant Questionnaire (CCIQ) as a tool for assessing changes in health-related quality of life (HRQoL) after receiving a second cochlear implant (CI2). Study Design Prospective study. Setting Academic cochlear implant center. Subjects and Methods The CCIQ is a 29-item questionnaire assessing the physical and psychosocial benefits of a CI2 based on a 5-point Likert scale. The CCIQ was administered with the Nijmegen Cochlear Implant Questionnaire and the Short Form-12 Patient Questionnaire (SF-12) to patients with a CI2. Speech perception was tested with the consonant-nucleus-consonant (CNC) word test and AzBio test. Results Of 56 patients, 32 (57.1%) completed the instruments sent by mail. Of the 32 patients, 22 (68.8%) completed retest CCIQs 6 weeks later. CCIQ scores demonstrated significantly increased HRQoL in all domains. Internal consistency was very good overall (Cronbach's α = 0.90), with all subdomains exceeding an alpha value of 0.70. Test-retest reliability was good, with an overall intraclass correlation of 0.62. The CCIQ showed a moderate correlation with the Nijmegen Cochlear Implant Questionnaire and a low correlation with the SF-12. Average CNC and AZBio scores significantly improved by 31% ± 29% and 34% ± 33%, respectively. Audiometric data were not significantly correlated with the CCIQ. Conclusion The CCIQ shows (1) good reliability and evidence of construct validity, (2) a significant increase in HRQoL and significantly improved speech perception after CI2, and (3) greater sensitivity at detecting CI2 improvements to HRQoL. This promising measure is quick and easy to administer and provides subjective assessments of HRQoL specifically for those with a CI2.

Dexamethasone's effect in the retrocochlear auditory centers of a noise-induced hearing loss mouse model.

OBJECTIVE: Examine prophylactic effects of dexamethasone (Dex) in retrocochlear auditory centers in a noise-induced hearing loss (NIHL) mouse model. STUDY DESIGN: Prospective animal study. SETTING: Academic research center. SUBJECTS AND METHODS: Thirty-two mice were divided into control, untreated, saline (2 and 10 µL), and Dex (2 and 10 µL) groups. Dex was applied intratympanically (IT) prior to 110 to 120 dB noise over 6 hours. Auditory brainstem response (ABR) and distortion product otoacoustic emission (DPOAE) were performed at 1 day, 1 week, 1 month, and 2 months. Retrocochlear neuronal cells were labeled with FluoroGold and counted. Hair cells of the organ of Corti were labeled with fluorescein isothiocyanate-conjugated phalloidin and counted. RESULTS: Auditory brainstem response thresholds of untreated NIHL, 2 and 10 µL IT saline, and 2 and 10 µL IT Dex were 21.7 ± 2.9 dB, 20 ± 0 dB, 20 ± 5 dB, 18.3 ± 2.9 dB, and 18.3 ± 2.9 dB, respectively. At 1-day post NIHL, all groups demonstrated profound hearing loss. At 2 weeks, 2 and 10 µL Dex thresholds improved to 47.5 ± 3.5 dB and 48.8 ± 18.9 dB, respectively, whereas the untreated and saline groups remained unchanged. Mean cell counts in the cochlear nucleus (CN), superior olivary complex (SOC), and lateral lemniscus (LL) of control mice were 1483 ± 190, 2807 ± 67, and 112 ± 20, respectively. After acoustic trauma, the untreated, saline, and 2 µL Dex groups yielded decreased neuronal counts in the SOC. In contrast, the 10 µL Dex group had 1883 ± 186 (CN), 2774 ± 182 (SOC), and 166 ± 18 (LL). There was sporadic hair cell loss for all traumatized groups. CONCLUSION: Our NIHL mouse model demonstrated dose-dependent Dex pretreatment otoprotection against NIHL with preservation of retrocochlear auditory neurons.

A new comprehensive cochlear implant questionnaire for measuring quality of life after sequential bilateral cochlear implantation.

OBJECTIVE: To develop a comprehensive cochlear implant questionnaire (CCIQ) as a tool for assessing changes in quality of life (QoL) after receiving a second cochlear implant (CI2) and to correlate the QoL with speech perception changes after CI2. STUDY DESIGN: Retrospective case series with planned data collection. SETTING: Academic cochlear implant center. PATIENTS: Ninety-eight English-speaking adults who received CI2 between 2000 and 2011. INTERVENTION: CCIQ is a 28-item, 5-point Likert-scale questionnaire that assesses the physical and psychosocial benefits of CI2. MAIN OUTCOME MEASURES: Test-retest reliability and Cronbach's alpha internal consistency were used to assess the reliability of the CCIQ. Speech perception was tested using CNC and HINT. RESULTS: Fifty-four patients completed the CCIQ, and 26 were retested. Respondents reported a subjective improvement in all domains. Test-retest reliability was satisfactory, with 64% of items achieving an intraclass correlation coefficient of greater than 0.6. Internal consistency reliability was excellent for the overall measure and was satisfactory for 6 of 9 subdomains. Speech perception data were available for 22 patients. Average CNC scores improved 13 ± 16%, and HINT scores improved 42 ± 16%. No statistically significant correlation was found between QoL scores and audiometric data or duration of CI2 use. CONCLUSION: Our preliminary data indicate that this CCIQ is a promising tool in assessing QoL specific to CI2 patients. Overall, patients reported improved QoL, independent of speech perception scores. Further refinements of the questionnaire with larger patient numbers are needed to strengthen the CCIQ.

Connexin 43 and hearing: possible implications for retrocochlear auditory processing.

OBJECTIVES/HYPOTHESIS: To examine the relationship between hearing and connexin 43, a dominant gap junctional protein in the central nervous system. STUDY DESIGN: Original research. METHODS: Connexin 43 heterozygous mice are used to assess its mutational effect on hearing. Results are compared to controls consisting of connexin 43, wild type and CBA/J mice. Hearing is assessed using auditory brainstem response and distortion product otoacoustic emissions tests. Distribution of connexin 43 in the organ of Corti and the retrocochlear auditory centers (eight nerve, cochlear nucleus, olivary complex, lateral lemniscus, inferior colliculus, respectively) is examined. Fluorescent markers are used to elucidate cell types. RESULTS: Mean click auditory brainstem response threshold for the young connexin 43 heterozygous mice (3-4 months) was 36.7 ± 12.6 dB compared to 25 ± 0 dB for control mice (P < 0.05). Mean threshold difference became more pronounced (68 ± 7.5 dB vs. 31 ± 2.2 dB) at 10 months (P < 0.05). Tonal auditory brainstem response testing showed elevated thresholds (>60 dB) at all frequencies (4-32 kHz) compared to the controls. Distortion product otoacoustic emissions (DPOAE) were present in all the mice, although the older connexin 43 heterozygous mice responded at higher thresholds. The pattern of connexin 43 immunoreactivity was distinctive from connexin 26 and 30, showing minimal presence in the organ of Corti but robustly present in the retrocochlear centers. CONCLUSION: Connexin 43 heterozygous mice demonstrated greater degree of hearing loss compared to age-matched controls. It is abundantly found in the retrocochlear auditory centers. The mechanism of hearing loss in these mice does not appear to be related to hair cell loss.

Efficacy of clobazam as add-on therapy for refractory epilepsy: experience at a US epilepsy center.

RATIONALE: Clobazam (CLB) has proven efficacy against multiple seizure types. Although available in many countries, it is not approved by the US Food and Drug Administration. The objective of this study was to evaluate the usage patterns, efficacy, tolerability, and 1-year retention of CLB in patients with refractory epilepsy seen at a tertiary US epilepsy center. METHODS: We retrospectively reviewed the use of CLB, 1 measure of efficacy (6-month seizure freedom), 1-year retention, and tolerability in patients with epilepsy who were prescribed CLB as part of their antiepileptic drug regimen at the Columbia Comprehensive Epilepsy Center over a 5-year period. RESULTS: Two hundred fifty-one patients were prescribed CLB, of which 62 were newly started on CLB at our center during this period (29 male and 33 female subjects; mean age, 43.9 years; range, 8-88 years). Clobazam dose ranged from 5 to 60 mg/d (mean, 23.9 mg/d). The mean number of previous antiepileptic drug trials per patient was 7.7. Of the 62 patients newly started on CLB, 7 patients (11.3%) became seizure-free for at least 6 months after introduction of CLB. Binary logistic regression was unable to identify any significant predictors of seizure freedom or CLB retention. Four patients remained seizure-free on CLB for more than 18 months. The Kaplan-Meier 12-month retention curve (n = 54 eligible patients) showed a 1-year retention rate of 61%. CONCLUSIONS: In this population of patients with highly refractory epilepsy at a US center, 11% of patients became seizure-free for at least 6 months after addition of CLB, and the 1-year retention rate was 61%.