Frequency-to-Place Mismatch Impacts Cochlear Implant Quality of Life, But Not Speech Recognition.

OBJECTIVE: To retrospectively compare frequency-place mismatch among adult cochlear implant (CI) recipients with lateral wall (LW) and perimodiolar/Mid Scala (PM/MS) arrays, and to quantify the impact of these factors on early post-activation (3 months) speech recognition abilities and CI-specific quality of life. METHODS: One hundred and twenty-six adult participants were separated into two groups: (1) 83 participants who underwent CI with a PM/MS array and 43 patients who underwent CI with a LW array. All participants completed the Cochlear Implant Quality of Life Profile (CIQOL-35 Profile) instrument. Angular insertion depth and semitone mismatch, which contribute to frequency-place mismatch, were assessed using post-operative CT scans. Word and speech recognition in quiet were determined using the Consonant-Nucleus-Consonant (CNC) and the AzBio tests, respectively (n = 82 patients). RESULTS: LW arrays were more deeply inserted and exhibited less semitone mismatch compared to PM/MS arrays. No significant relationship was found between semitone mismatch and early post-operative speech perception scores for either PM/MS or LW arrays. However, greater degrees of semitone mismatch were associated with lower CIQOL-35 profile scores for PM/MS arrays. CONCLUSIONS AND RELEVANCE: The results of this study indicate that both the degree of frequency-place mismatch, and its impact on CI-specific quality of life, vary by CI array design. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:2898-2905, 2024.

Short Postoperative Length of Stay After Lateral Cerebrospinal Fluid Leak Repair.

OBJECTIVE: To characterize the short-term outcomes of patients undergoing surgical repair of lateral skull base cerebrospinal fluid (CSF) leaks followed by a shortened length of stay (LOS) protocol. STUDY DESIGN: Retrospective study. SETTING: Tertiary medical center. METHODS: A total of 156 adult patients from July 2016 to December 2022 who underwent repair of CSF leaks via transmastoid (TM), middle cranial fossa (MCF), or combined (TM/MCF) approaches were included. Data collected included: LOS, presentation to the emergency department (ED), need for readmission, major neurologic complications (stroke, seizure, and meningitis), and CSF leak recurrence. RESULTS: Approximately half of patients underwent a TM repair (49.4%), whereas the other half underwent either an MCF (3.8%) or combined TM/MCF repair (46.8%). No peri-/postoperative lumbar drains were used and only 2 (1.3%) patients were admitted to the intensive care unit after surgery. Mean LOS for the cohort was 1.1 ± 0.7 days and was longer for surgeries involving MCF (1.3 ± 0.6) compared to TM (0.8 ± 0.7). Ninety-two percent of TM cases were discharged within 24 hours (32% on the same day) while for cases involving an MCF approach, 72.2% of patients were discharged within 24 hours. Of the patients in the study, 6 (3.8%) presented to an ED for minor complications and no patient required readmission. Revision surgery was required for 3 (1.9%) patients for recurrent CSF leak. CONCLUSION: Our findings suggest that short LOS after surgical repair of lateral skull base defects in the treatment of CSF leak is safe and effective.

Elevated Body Mass Index Associated with Cerebrospinal Fluid Leak after Lateral Skull Base Surgery: A Systematic Review and Meta-analysis.

OBJECTIVE: To determine if body mass index (BMI) increases the risk of cerebrospinal fluid (CSF) leak after lateral skull base surgery. DATA SOURCES: CINAHL, PubMed, and Scopus were searched from January 2010 to September 2022 for articles published in English. STUDY SELECTION: Articles that reported BMI or obesity with and without CSF leaks after lateral skull base surgery were included. DATA EXTRACTION: Two reviewers (F.G.D. and B.K.W.) independently performed study screening, data extraction, and risk of bias assessment. DATA SYNTHESIS: A total of 11 studies and 9,132 patients met inclusion criteria. Meta-analysis of mean difference (MD), odds ratio (OR), proportions, and risk ratio (RR) were calculated using RevMan 5.4 and MedCalc 20.110. BMI for patients with CSF leak after lateral skull base surgery (29.39 kg/m 2 , 95% confidence interval [CI] = 27.75 to 31.04) was significantly greater than BMI for patients without CSF leak after lateral skull base surgery (27.09 kg/m 2 , 95% CI = 26.16 to 28.01) with an MD of 2.21 kg/m 2 (95% CI = 1.09 to 3.34, p = 0.0001). The proportion of patients with BMI ≥ 30 kg/m 2 that had a CSF leak was 12.7%, and the proportion of patients with BMI < 30 kg/m 2 (control) that had a CSF leak was 7.9%. The OR for CSF leak after lateral skull base surgery in patients with BMI ≥ 30 kg/m 2 was 1.94 (95% CI = 1.40 to 2.68, p < 0.0001), and the RR was 1.82 (95% CI = 1.36 to 2.43, p < 0.0001). CONCLUSION: Elevated BMI increases the risk of CSF leak after lateral skull base surgery. LEVEL OF EVIDENCE: IIa.

Why Do Candidates Forgo Cochlear Implantation?

OBJECTIVE: Identify barriers and facilitating factors in cochlear implant (CI) utilization by comparing functional measures between CI candidates who undergo or forgo implantation. METHODS: Forty-three participants were separated into two groups: (1) 28 participants who underwent CI and (2) 15 participants who elected not to proceed with CI despite meeting eligibility criteria (no-CI). Prior to implantation, all participants completed the CI Quality of Life (CIQOL)-35 Profile and CIQOL-Expectations instrument. They were also surveyed on factors contributing to their decision to either undergo or forgo CI. Word and speech recognition were determined using the Consonant-Nucleus-Consonant (CNC) and the AzBio tests, respectively. RESULTS: CIQOL-Expectations scores were indistinguishable between groups, but there were substantial differences in baseline CIQOL-35 Profile scores. Compared to the CI group, the no-CI group exhibited higher pre-CI scores in the Emotional (Cohen's d [95% CI] = 0.8 [0.1, 1.5]) and Entertainment (Cohen's d [95% CI] = 0.8 [0.1, 1.5]) domains. Survey data revealed that the most commonly reported barriers to pursuing CI in the no-CI cohort were fear of surgical complications (85%), cost associated with implantation (85%), and perception that hearing was not poor enough for CI surgery (85%). CONCLUSIONS AND RELEVANCE: The results of this study indicate that functional outcome expectations are similar between candidates who elect to receive or forgo CI, yet those who forgo CI have higher baseline CI-specific QOL abilities. LEVEL OF EVIDENCE: 4 Laryngoscope, 133:3548-3553, 2023.

Neurophysiological profiles of responders and nonresponders to hypoglossal nerve stimulation: a single-institution study.

STUDY OBJECTIVES: Hypoglossal nerve stimulation (HGNS) is an effective alternative treatment for obstructive sleep apnea that acts by opening the airway via selective stimulation of nerve fibers that innervate tongue muscles that protrude (genioglossus) and stiffen the tongue (transverse and vertical) while avoiding nerve fibers that innervate tongue muscles that retract the tongue (styloglossus and hyoglossus). There remains a subset of postoperative patients who fail to adequately respond to HGNS, in some cases due to mixed activation of muscles that simultaneously protrude and retract the tongue. This study aims to characterize the relationship between neurophysiological data from individual tongue muscle activation during intraoperative electromyographic recordings and postoperative apnea-hypopnea index responses to HGNS. METHODS: A single-institution review of 46 patients undergoing unilateral HGNS implantation for obstructive sleep apnea. Patients were separated into responders and nonresponders through comparison of pre and postoperative apnea-hypopnea index. Neurophysiological data included electromyographic responses of the genioglossus, styloglossus/hyoglossus, intrinsic/vertical, and hyoglossus (neck) muscles to intraoperative stimulation using unipolar (- to - and o to o) and bipolar (+ to +) settings. RESULTS: The overall treatment success rate was 61% as determined by a postoperative apnea-hypopnea index < 20 events/h with a greater than 50% AHI reduction. We observed no statistically significant relationships between treatment response and individual muscle responses. However, we did note that increasing body mass index was correlated with worse postoperative responses. CONCLUSIONS: Although we noted a significant subgroup of clinical nonresponders to HGNS postoperatively, these patients were not found to exhibit significant inclusion of tongue retractors intraoperatively on neurophysiological analysis. Further research is needed to delineate additional phenotypic factors that may contribute to HGNS treatment responses. CITATION: Wang D, Modik O, Sturm JJ, et al. Neurophysiological profiles of responders and nonresponders to hypoglossal nerve stimulation: a single-institution study. J Clin Sleep Med. 2022;18(5):1327-1333.

Comparative Performance of Lateral Wall and Perimodiolar Cochlear Implant Arrays.

OBJECTIVE: The physical shape of cochlear implant (CI) arrays may impact hearing outcomes. The goal of this study was to compare post-operative speech and melody perception between patients with lateral wall (LW) and perimodiolar (PM) electrode arrays across a range of lengths and manufacturers. STUDY DESIGN: Retrospective chart review. SETTING: Tertiary Care Hospital. PATIENTS: 119 adult patients with post-lingual hearing loss who underwent cochlear implantation. MAIN OUTCOME MEASURES: A total of seven different electrodes were evaluated including 5 different LW electrodes (CI422 [Cochlear American], 1J [Advanced Bionics], Medium [Med El], Standard [Med El], Flex28 [Med El]) and 2 PM electrodes (Contour [Cochlear American], MidScala [Advanced Bionics]). Speech perception outcomes (n = 119 patients) were measured by Consonant-Nucleus-Consonant (CNC) scores collected 3, 6, 12 and 24 months after implantation. Melody perception outcomes (n = 35 CI patients and n = 6 normal hearing patients) were measured by Melodic Contour Identification (MCI). RESULTS: CNC scores increased over time after implantation across all array designs. PM designs exhibited higher CNC scores compared to LW electrodes, particularly 6-months after implantation. Pre-operative pure tone averages did not correlate with post-operative CNC scores. PM arrays outperformed LW electrodes in terms of MCI scores. CONCLUSIONS: The physical shape of cochlear implant electrode arrays may impact hearing performance. Compared to LW designs, PM arrays appear to offer superior speech perception during the first 6 months after implantation, with performance equalizing between groups by 24 months. Compared to LW designs, PM arrays also appear to afford superior melody perception.

Comparison of Speech Performance in Bimodal versus Bilateral Cochlear Implant Users.

OBJECTIVE: To assess whether listening with two cochlear implants (bilateral) offers significant benefits in terms of speech perception over listening with one cochlear implant and one hearing aid (bimodal). METHODS: Retrospective review of bilateral cochlear implant recipients (24 pediatric and 26 adult). Bimodal listening was compared to bilateral listening in terms of speech perception performance at 1-year post second implant under three listening conditions: 50 dBHL, 35 dBHL, and 50 dBHL+5 SNR. Changes in speech performance from bimodal (before second implant) to bilateral (after second implant) listening were determined within subjects and compared to a separate control group of bimodal users matched for age of first implantation who never received a second implant (10 pediatric and 20 adult). RESULTS: In the pediatric group, compared to bimodal listening prior to a second implant, speech perception scores with bilateral implants increased significantly when measured at 50 dBHL, 35 dBHL, and 50 dBHL+5 SNR. By contrast, pediatric bimodal controls who never received a second implant failed to demonstrate similar improvement over 1 year's time. In the adult group, compared to bimodal listening prior to a second implant, speech perception scores with bilateral implants increased when measured at 50 dBHL, but were not significantly different at 35 dBHL and 50 dBHL + 5 SNR. Adult bimodal controls who never received a second implant failed to demonstrate significant improvement in all conditions over 1 year's time. CONCLUSION: Bilateral listening with two cochlear implants improved speech perception performance relative to bimodal listening in the pediatric population. Improvement in the adult population was not as significant. LEVEL OF EVIDENCE: 4, Retrospective Chart Review. Laryngoscope, 131:E1322-E1327, 2021.