Phase I trial of caudate deep brain stimulation for treatment-resistant tinnitus.

OBJECTIVE: The objective of this open-label, nonrandomized trial was to evaluate the efficacy and safety of bilateral caudate nucleus deep brain stimulation (DBS) for treatment-resistant tinnitus. METHODS: Six participants underwent DBS electrode implantation. One participant was removed from the study for suicidality unrelated to brain stimulation. Participants underwent a stimulation optimization period that ranged from 5 to 13 months, during which the most promising stimulation parameters for tinnitus reduction for each individual were determined. These individual optimal stimulation parameters were then used during 24 weeks of continuous caudate stimulation to reach the endpoint. The primary outcome for efficacy was the Tinnitus Functional Index (TFI), and executive function (EF) safety was a composite z-score from multiple neuropsychological tests (EF score). The secondary outcome for efficacy was the Tinnitus Handicap Inventory (THI); for neuropsychiatric safety it was the Frontal Systems Behavior Scale (FrSBe), and for hearing safety it was pure tone audiometry at 0.5, 1, 2, 3, 4, and 6 kHz and word recognition score (WRS). Other monitored outcomes included surgery- and device-related adverse events (AEs). Five participants provided full analyzable data sets. Primary and secondary outcomes were based on differences in measurements between baseline and endpoint. RESULTS: The treatment effect size of caudate DBS for tinnitus was assessed by TFI [mean (SE), 23.3 (12.4)] and THI [30.8 (10.4)] scores, both of which were statistically significant (Wilcoxon signed-rank test, 1-tailed; alpha = 0.05). Based on clinically significant treatment response categorical analysis, there were 3 responders determined by TFI (≥ 13-point decrease) and 4 by THI (≥ 20-point decrease) scores. Safety outcomes according to EF score, FrSBe, audiometric thresholds, and WRS showed no significant change with continuous caudate stimulation. Surgery-related and device-related AEs were expected, transient, and reversible. There was only one serious AE, a suicide attempt unrelated to caudate neuromodulation in a participant in whom stimulation was in the off mode for 2 months prior to the event. CONCLUSIONS: Bilateral caudate nucleus neuromodulation by DBS for severe, refractory tinnitus in this phase I trial showed very encouraging results. Primary and secondary outcomes revealed a highly variable treatment effect size and 60%-80% treatment response rate for clinically significant benefit, and no safety concerns. The design of a phase II trial may benefit from targeting refinement for final DBS lead placement to decrease the duration of the stimulation optimization period and to increase treatment effect size uniformity.Clinical trial registration no.: NCT01988688 (clinicaltrials.gov).

TeleAudiology in the Veterans Health Administration.

OBJECTIVE: To assess effectiveness of TeleAudiology for hearing aid services. STUDY DESIGN: Retrospective case-control. SETTING: Ambulatory Veterans Health Administration and Community-Based Outpatient Clinics (CBOCs). PATIENTS: 42,697 veterans who received hearing aids from January through September, 2014. INTERVENTION(S): TeleAudiology (TA) and conventional in-person (IP) audiology care. MAIN OUTCOME MEASURE(S): International Outcome Inventory for Hearing Aids (IOI-HA) outcomes data. The IOI-HA is a 7-item survey used to assess hearing aid effectiveness. Scored from 7 to 35 points, higher scores are more favorable. RESULTS: Among veterans nationwide who received hearing aids and completed the IOI-HA survey, 1,009 received TA and 41,688 received IP care. TA and IP groups have comparable mean IOI-HA values (TA = 29.6, SD = 3.9; IP = 28.7, SD = 4.2). Although comparison showed a statistically significant difference (p < 0.0001, t test), principally because of large sample size, the distinction is not clinically meaningful.Subgroup analysis of veterans from San Francisco and six affiliated CBOCs showed 169 received TA and 338 received IP care. TA and IP groups have similar mean age (TA = 74, SD = 9.8; IP = 76, SD = 10.3) and sex distribution (TA male = 100%; IP male = 96%) with statistically significant (p < 0.01, t test) but clinically insignificant differences. Mean IOI-HA scores (TA = 30.7, SD = 3.6; IP = 30.5, SD = 3.1) are not different between groups (p > 0.05, t test). CONCLUSION: TA and IP encounters to provide hearing aid services to veterans are comparable, as both are highly effective based on IOI-HA results. The noninferiority of TA suggests its adoption to non-veterans may improve access while preserving high satisfaction. Financial impact of migration to TA will require future econometric analysis.

Validation of a screening test of auditory function using the telephone.

BACKGROUND: Several European countries have demonstrated successful use of telephone screening tests for auditory function. The screening test consists of spoken three-digit sequences presented in a noise background. The speech-to-noise ratios of the stimuli are determined by an adaptive tracking method that converges on the level required to achieve 50% correct recognition. PURPOSE: A version of the three-digit telephone screening protocol for the United States was developed: the US National Hearing Test (NHT). The objective of the current study was to determine the sensitivity and specificity as well as the feasibility of the NHT for use within the Department of Veterans Affairs (VA). Research Design and Study Sample: Using a multisite study design with convenience sampling, we used the NHT to collect data from 693 participants (1379 ears) from three geographical areas of the United States (Florida, Tennessee, and California). DATA COLLECTION AND ANALYSIS: The NHT procedures were as follows: the participants (1) called a toll-free telephone number, (2) entered their assigned ear-specific identification code, (3) listened to 40-sets of digit triplets presented in speech-spectrum background noise, and (4) entered in the numbers that they heard on the telephone key pad. The NHT was performed on each ear, either at home or in a VA clinic. In addition to collecting data from the experimental task, we gathered demographic data and the data from other standard-of-care tests (i.e., audiometric thresholds and speech recognition tests in quiet and in noise). RESULTS: A total of 505 participants completed the NHT at a VA clinic, whereas 188 completed the test at home. Although the ear-specific NHT and mean pure-tone threshold all correlated significantly (p < 0.001), there were more modest correlations in the low- and high-frequency ranges with the highest correlation seen with the 2000 Hz mean pure-tone threshold. When the NHT 50% point or threshold was compared with the three-frequency PTA at 500, 1000, and 2000 Hz, the sensitivity was 0.87 and specificity was 0.54. When comparing the NHT with the four-frequency PTA at 500, 1000, 2000, and 4000 Hz, the sensitivity was 0.81 and specificity increased to 0.65. The NHT also correlated strongly with other speech-in-noise measures. CONCLUSIONS: The NHT was found to correlate with other audiometric measures, including pure-tone thresholds and speech recognition tests in noise, at sufficiently high correlation values to support its use as a screening test of auditory function.