The authors developed a new disease-specific patient-reported outcome measure to capture the multifaceted impacts of vestibular schwannoma on daily life, the Vestibular Schwannoma Quality of Life (VSQOL) Index, which contains 40 items grouped into eight categories: hearing problems; dizziness and imbalance; pain, discomfort, and tinnitus; problems with face or eyes; impact on physical, emotional, and social well-being; difficulty with thinking and memory; satisfaction or regret; and impact on employment. 1 The VSQOL Index was developed in English, although the availability of this instrument in other languages can improve access to quality of life (QOL) research worldwide with enhanced racial, ethnic, and geographic representation. The authors partnered with FACITtrans, a component of the Functional Assessment of Chronic Illness Therapy (FACIT) group with more than 25 years of experience in translation, cultural adaptation, and linguistic validation of patient-reported outcome measures, to translate the VSQOL Index to Arabic using a rigorous translation methodology. 2–5 The translation of the VSQOL Index presented at the end of this article may be used for noncommercial research, clinical, or educational purposes without seeking written permission from the authors. By providing a suite of translations in this digital supplement of the Journal of Neurosurgery , the authors hope to increase the reach and breadth of QOL research and facilitate international collaborations.
Spanish translation of the Mayo Clinic Vestibular Schwannoma Quality of Life Index
The authors developed a new disease-specific patient-reported outcome measure to capture the multifaceted impacts of vestibular schwannoma on daily life, the Vestibular Schwannoma Quality of Life (VSQOL) Index, which contains 40 items grouped into eight categories: hearing problems; dizziness and imbalance; pain, discomfort, and tinnitus; problems with face or eyes; impact on physical, emotional, and social well-being; difficulty with thinking and memory; satisfaction or regret; and impact on employment. 1 The VSQOL Index was developed in English, although the availability of this instrument in other languages can improve access to quality of life (QOL) research worldwide with enhanced racial, ethnic, and geographic representation. The authors partnered with FACITtrans, a component of the Functional Assessment of Chronic Illness Therapy (FACIT) group with more than 25 years of experience in translation, cultural adaptation, and linguistic validation of patient-reported outcome measures, to translate the VSQOL Index to Spanish using a rigorous translation methodology. 2–5 The translation of the VSQOL Index presented at the end of this article may be used for noncommercial research, clinical, or educational purposes without seeking written permission from the authors. By providing a suite of translations in this digital supplement of the Journal of Neurosurgery , the authors hope to increase the reach and breadth of QOL research and facilitate international collaborations.
Japanese translation of the Mayo Clinic Vestibular Schwannoma Quality of Life Index
The authors developed a new disease-specific patient-reported outcome measure to capture the multifaceted impacts of vestibular schwannoma on daily life, the Vestibular Schwannoma Quality of Life (VSQOL) Index, which contains 40 items grouped into eight categories: hearing problems; dizziness and imbalance; pain, discomfort, and tinnitus; problems with face or eyes; impact on physical, emotional, and social well-being; difficulty with thinking and memory; satisfaction or regret; and impact on employment. 1 The VSQOL Index was developed in English, although the availability of this instrument in other languages can improve access to quality of life (QOL) research worldwide with enhanced racial, ethnic, and geographic representation. The authors partnered with FACITtrans, a component of the Functional Assessment of Chronic Illness Therapy (FACIT) group with more than 25 years of experience in translation, cultural adaptation, and linguistic validation of patient-reported outcome measures, to translate the VSQOL Index to Japanese using a rigorous translation methodology. 2–5 The translation of the VSQOL Index presented at the end of this article may be used for noncommercial research, clinical, or educational purposes without seeking written permission from the authors. By providing a suite of translations in this digital supplement of the Journal of Neurosurgery , the authors hope to increase the reach and breadth of QOL research and facilitate international collaborations.
A Multi-Institutional Analysis of Device Failures in a Recent Cochlear Implant Series
Objective To assess Advanced Bionics (AB) HiRes Ultra and Ultra 3D initial version (V1) cochlear implant electrode failures over time at four large cochlear implant programs. Study Design Retrospective cohort. Setting Four tertiary referral centers. Patients Patients receiving AB HiRes Ultra and Ultra 3D initial version (V1) devices as of December 31, 2022. Main Outcome Measures Failure rate, revision surgery, speech recognition scores. Results Over a span of 7 years, 205 (42.6%) of 483 implanted V1 devices have failed. Device failure rate varied across institutions from 32 to 67%. Of the 205 detected failures, 163 (79%) have undergone revision surgery, with 94% of revisions being performed with Advanced Bionics devices. Average time from implantation to diagnosis of device failure was 2.7 ± 1.2 years. Most patients (89.8%) with available testing were matched or exceeded their best prefailure speech performance after implant revision. After revision, patients had an average CNC score improvement of 24.7 percentage points over their most recent pre-revision scores and demonstrated average datalogging of 12.7 ± 4.1 h/d at most recent evaluation. Conclusions Comparison of patients across multiple high-volume implant centers confirms the presence of ongoing device failures. There is variability across institutions in the rate of revision surgery once a patient is diagnosed with a V1 device failure, as well as in the rate of device failure detection. Inter-institutional variability in failure rates may be explained by the variation in the routine use of electrical field imaging. Reimplantation with a new device typically results in a return to prefailure peak performance. Professional Practice Gap & Educational Need To our knowledge, a comparison of AB HiRes (V1) device failures across multiple institutions has not been conducted. Learning Objective To identify device failure rate across multiple institutions with different testing protocols. Desired Result Providers will have an improved understanding of the trajectory of device failures for HiRes (V1) devices over time. Level of Evidence Level IV—Historical cohort or case-controlled studies. Indicate IRB or IACUC IRB #230017; IRB #22-000183; IRB #STU-032018-085; IRB #H-49479.
Longitudinal Trends in Cochlear Implant Programming from a Single-Institution Review of Over 400 Adult Implant Recipients: Evidence to Support Selective De-Escalation of Device Programming
Objective To examine comfort (C) and threshold (T) levels in adult cochlear implant (CI) recipients over the first 18 months postactivation. Study Design Retrospective review of longitudinal CI programming data. Setting Tertiary academic center. Patients A total of 480 CIs among 428 adult CI recipients. Interventions Cochlear implantation with Cochlear Ltd. devices with subsequent programming to behavioral standards using Custom Sound® fitting software. Main Outcome Measures Charge levels needed to achieve C and T levels were measured longitudinally using Custom Sound®, from time of activation to a minimum of 6 and a maximum of 18 months postactivation. Charge (nC) levels were calculated as the product of pulse width (μs) and current amplitude (μA) to standardize among implant models. Changes in C and T charge levels over time were evaluated using repeated-measures analysis of variance. Results When considering the entire electrode, the largest increases were seen at 1 month postactivation, and C and T charge levels did not increase significantly after 6 and 12 months, respectively. These findings were consistent across patient age at implantation and sex. When considering proximal electrodes only, C and T levels did not increase significantly after 6 months. In distal electrodes only, C levels did not increase significantly after 6 months, but T levels continued to demonstrate small, but statistically significant increases up to 18 months postactivation. Conclusions Across the entire electrode, we observed the largest changes in C and T charge levels at 1 month postactivation. Small increases in C and T levels continued out to 6 and 12 months, respectively, but may be of limited clinical significance. The stability of programming levels over time may support selective de-escalation of CI follow-up after the initial postactivation period, but, given small yet persistent increases with time, most notably in the distal electrodes, alternatives for follow-up or remote programming may still be encouraged.
Detection of Extracochlear Electrodes Using Electrical Field Imaging (EFI)
Objective To analyze the use of electrical field imaging (EFI) in the detection of extracochlear electrodes in cochlear implants (CI) Study Design Retrospective cohort study Setting Tertiary academic medical center Methods EFI patterns from 6 recipients with extracochlear electrodes were compared with 10 recipients with all intracochlear electrodes to identify differences in EFI patterns between these two groups. For the extracochlear group, EFI patterns were analyzed using two methods: visual inspection and calculation of the average impedance difference (AID) between specific EFI curves. These results were then compared with information from CT and plain film imaging, surgical notes, and audiology tests to confirm the placement of the electrodes in each recipient. Results An average AID of 0.06 kΩ was calculated from the EFI patterns for recipients with complete electrode insertion, whereas an average AID of 0.15 kΩ was calculated from the EFI curves measured for the extracochlear electrodes. Visual analysis of the EFI impedance curves for extracochlear electrodes showed a distinct separation from those measured for intracochlear electrodes. Based on AID analysis and visual inspection the EFI, patterns were in close agreement with the number of extracochlear electrodes detected based on either imaging, intraoperative surgical note, or audiological findings. Conclusion EFI is a noninvasive, inexpensive, and time-efficient measurement that can be used to detect extracochlear electrodes and monitor electrode migration from the cochlea.
How Does Deep Neural Network-Based Noise Reduction in Hearing Aids Impact Cochlear Implant Candidacy?
Background/Objectives: Adult hearing-impaired patients qualifying for cochlear implants typically exhibit less than 60% sentence recognition under the best hearing aid conditions, either in quiet or noisy environments, with speech and noise presented through a single speaker. This study examines the influence of deep neural network-based (DNN-based) noise reduction on cochlear implant evaluation. Methods: Speech perception was assessed using AzBio sentences in both quiet and noisy conditions (multi-talker babble) at 5 and 10 dB signal-to-noise ratios (SNRs) through one loudspeaker. Sentence recognition scores were measured for 10 hearing-impaired patients using three hearing aid programs: calm situation, speech in noise, and spheric speech in loud noise (DNN-based noise reduction). Speech perception results were compared to bench analyses comprising the phase inversion technique, employed to predict SNR improvement, and the Hearing-Aid Speech Perception Index (HASPI v2), utilized to predict speech intelligibility. Results: The spheric speech in loud noise program improved speech perception by 20 to 32% points as compared to the calm situation program. Thus, DNN-based noise reduction can improve speech perception in noisy environments, potentially reducing the need for cochlear implants in some cases. The phase inversion method showed a 4–5 dB SNR improvement for the DNN-based noise reduction program compared to the other two programs. HASPI v2 predicted slightly better speech intelligibility than was measured in this study. Conclusions: DNN-based noise reduction might make it difficult for some patients with significant residual hearing to qualify for cochlear implantation, potentially delaying its adoption or eliminating the need for it entirely.
Intraoperative Electrical Stapedius Reflex Testing to Monitor Cochlear Nerve Integrity during Simultaneous Vestibular Schwannoma Resection and Cochlear Implantation
Objective To compare the utility of intraoperative electrically evoked auditory brainstem response (eABR) and electrically evoked stapedial reflex testing (eSRT) for cochlear nerve integrity monitoring during simultaneous translabyrinthine resection of vestibular schwannoma (VS) and cochlear implantation. Study design Historical cohort study. Setting Tertiary academic referral center. Patients Eleven patients (12 cases) who underwent translabyrinthine tumor resection with simultaneous placement of a standard, unmodified cochlear implant (CI). Intervention A CI placed at the beginning of the operation before tumor resection to facilitate intraoperative cochlear nerve monitoring through a CI-delivered electrical stimulus. Main outcome measure Correlation of intraoperative monitoring outcomes with postoperative CI performance. Results Among the 12 cases (median age, 47 years), eABR waveforms were present at the conclusion of tumor resection in 10, including 6 that achieved open set speech perception. Of the 2 cases with negative eABR, 1 achieved open set speech perception. By contrast, of the 8 cases with a positive eSRT response, 7 achieved open set speech perception. Of the 4 cases with a negative eSRT response, none achieved open set speech perception. The 3 cases that did not receive auditory stimulation included 2 with positive and 1 with negative eABR; all 3 had a negative eSRT response. Conclusions Intraoperative eSRT using an unmodified CI is a promising new method for monitoring the integrity of the cochlear nerve during simultaneous VS resection. eSRT response at the conclusion of tumor resection strongly correlated with CI open set speech capacity. Although still useful, eABR was less reliable at predicting postoperative hearing outcomes in this series.
A Novel Algorithm to Analyze Multi-Frequency Electrocochleography Measurements to Monitor Electrode Placement During Cochlear Implant Surgery
Objectives: During cochlear implant (CI) electrode placement, single low-frequency (e.g., 500 Hz) cochlear microphonics (CM) measurements are used to monitor hair-cell function and provide feedback to avert insertion trauma. However, it can be difficult to differentiate between trauma and the electrode’s progression through the cochlea when monitored with a single frequency. Multi-frequency CM measurements, while more complex to analyze, can provide more accurate feedback by measuring CM from various locations along the basilar membrane. Methods: A new algorithm was developed to analyze multi-frequency CM tracings by comparing amplitude and phase changes across different test frequencies. The new algorithm was evaluated as to its ability to identify drop-alarm instances with the multi-frequency approach, as compared to single-frequency 500 Hz tracings. Results: The algorithm presented in this manuscript uses the relationship between CM amplitude and phase changes across frequencies to provide real-time feedback during CI electrode placement. The results show that multi-frequency CM tracings raised an alarm only 0.5 times, as compared to 2.8 instances of alarm raised for the single-frequency 500 Hz CM measurements. Conclusions: Multi-frequency CM tracings can help reduce the number of alarms which may be false positives prompting unnecessary electrode manipulations, thereby minimizing the risk of insertion trauma.
Pathophysiology of Facial Nerve Stimulation and Its Implications for Electrical Stimulation in Cochlear Implants
Objectives A small number of cochlear implant (CI) users experience facial nerve stimulation (FNS), which can manifest as facial twitching. In some patients, this can be resolved by adjusting the electrical stimulation parameters. However, for others, facial stimulation can significantly impair CI outcomes or even prevent its use. The exact mechanisms underlying FNS are unclear and may vary among patients. Design Transimpedance measurements were used to assess lateral and longitudinal spread of current within 15 cochlea of nucleus CI recipients with FNS (13 unilateral recipients and 1 bilateral recipient). We compared the transimpedance measurements with programming parameters from clinical visits and pre- and postoperative temporal bone computed tomography (CT) scans to identify factors that may contribute to FNS in each CI ear. Results In nine ears, transimpedance curves showed inflection, which suggests a localized current sink within the cochlea. This indicates a low-impedance pathway through which current exits the cochlea and stimulates the labyrinthine segment of the facial nerve canal. Electrodes near this current sink were disabled or underfit to minimize facial stimulation. In the other seven ears, current flow peaked toward the basal end of the cochlea, suggesting that current exits through the round window or other structures near the basal end of the cochlea, stimulating the tympanic segment of the facial nerve. Conclusions Objective transimpedance measurements can be used to elucidate the mechanisms of FNS and to develop strategies for optimizing electrical stimulation parameters and speech coding to minimize or eliminate FNS in a small subset of CI users.