Effects of Glycerol Test on Resonance Frequency in Patients with Ménière’s Disease
Objective: To evaluate resonance frequency (RF) values via dehydration effects in the inner ear caused by the glycerol test, which is used as a diagnostic method for Ménière’s disease (MD). Methods: Twenty adult patients with unilateral MD were included in the study. Before, and then at 1, 2, and 3 h after administration of glycerol (1 g/kg), pure-tone hearing levels (125–8,000 k
Hz) and multifrequency tympanometry tests were performed. As a control, the RF values of the ears of 25 healthy subjects (i.e., 50 ears) were compared to the affected and unaffected ears in the 20 MD patients. Results: There was a significant difference between the RF values of affected and healthy ears before glycerol administration (p = 0.047). The RF values before and after glycerol administration into affected ears were compared. The average RF values decreased significantly from 748.0 ± 402.1 to 808.0 ± 410.1 Hz at 1 h after glycerol intake, and this value increased during the subsequent hours. There were no statistically significant differences between the pure-tone levels before and 1 h after glycerol administration, but a significant decrease was observed at 3 h. Conclusion: We suggest that MD has different inner-ear dynamics and normal RF values when compared to healthy ears. Furthermore, decreased inner ear pressure causes reduction of the mass effect and a stiffening of the annular ligament. We conclude that pre- and post-RF tests should be added to the test battery for diagnosis of MD.
BalanCI: Head-Referenced Cochlear Implant Stimulation Improves Balance in Children with Bilateral Cochleovestibular Loss
01-11-2019 – NE Wolter,KA Gordon,JL Campos,LD Vilchez Madrigal,DD Pothier,CO Hughes,BC Papsin,SL Cushing
Introduction: To determine the impact of a head-referenced cochlear implant (CI) stimulation system, Balan
CI, on balance and postural control in children with bilateral cochleovestibular loss (BCVL) who use bilateral CI. Methods: Prospective, blinded case-control study. Balance and postural control testing occurred in two settings: (1) quiet clinical setting and (2) immersive realistic virtual environment (Challenging Environment Assessment Laboratory CEAL, Toronto Rehabilitation Institute). Postural control was assessed in 16 and balance in 10 children with BCVL who use bilateral CI, along with 10 typically developing children. Children with neuromotor, cognitive, or visual deficits that would prevent them from performing the tests were excluded. Children wore the Balan
CI, which is a head-mounted device that couples with their CIs through the audio port and provides head-referenced spatial information delivered via the intracochlear electrode array. Postural control was measured by center of pressure (COP) and time to fall using the Wii
TM (Nintendo, WA, USA) Balance Board for feet and the Balan
CI for head, during the administration of the Modified Clinical Test of Sensory Interaction in Balance (CTSIB-M). The COP of the head and feet were assessed for change by deviation, measured as root mean square around the COP (COP-RMS), rate of deviation (COP-RMS/duration), and rate of path length change from center (COP-velocity). Balance was assessed by the Bruininks-Oseretsky Test of Motor Proficiency 2, balance subtest (BOT-2), specifically, BOT-2 score as well as time to fall/fault. Results: In the virtual environment, children demonstrated more stable balance when using Balan
CI as measured by an improvement in BOT-2 scores. In a quiet clinical setting, the use of Balan
CI led to improved postural control as demonstrated by significant reductions in COP-RMS and COP-velocity. With the use of Balan
CI, the number of falls/faults was significantly reduced and time to fall increased. Conclusions: Balan
CI is a simple and effective means of improving postural control and balance in children with BCVL who use bilateral CI. Balan
CI could potentially improve the safety of these children, reduce the effort they expend maintaining balance and allow them to take part in more complex balance tasks where sensory information may be limited and/or noisy.
Is Early Cochlear Implant Device Activation Safe for All on-the-Ear and off-the-Ear Sound Processors?
30-10-2019 – MO Batuk,M Yarali,BC Cinar,AP Kocabay,MD Bajin,G Sennaroglu,L Sennaroglu
Background: Cochlear implantation (CI) is an effective treatment option for patients with severe-to-profound hearing loss. When CI first started, it was recommended to wait until at least 4 weeks after the CI surgery for the initial activation because of possible complications. Advances in the surgical techniques and experiences in fitting have made initial activation possible within 24 h. Objectives: To compare the complaints and complications after early activation between behind-the-ear (BTE) and off-the-ear (OTE) sound processors and to show the impact of early activation on the electrode impedance values. Method: CI surgeries performed between March 2013 and July 2018 were retrospectively analyzed from the database. In total, 294 CI users were included in the present study. The impedance measurements were analyzed postoperatively at the initial activation prior to the stimulation, and 4 weeks after the initial activation in the first-month follow-up visit. A customized questionnaire was administered in the first-month follow-up fitting session to caregivers and/or patients who were using CI at least for 6 months. Medical records were also reviewed to identify any postoperative complications. Results: In the early activation group, impedance values were significantly lower than in the control group (p #x3c; 0.05) at first fitting. At the first-month follow-up, no significant difference was found between the groups (p #x3e; 0.05). The most common side effects were reported to be edema (6.1%) and pain (5.7%) in the early activation group. In patients with OTE sound processors, the rate of side effects such as skin infection, wound swelling, skin hyperemia, and pain was higher than in patients with BTE sound processors; however, a statistical significance was only observed in wound swelling (p = 0.005). Selecting the appropriate magnet was defined as a problem for the OTE sound processors during the initial activation. Conclusion: This study revealed that early activation of CI was clinically safe and feasible in patients with BTE sound processors. When using OTE sound processors, the audiologists should be careful during the activation period and inform patients of possible side effects. The first fitting should be delayed for 4 weeks after CI for OTE sound processors. This current study is the first to report this finding with 5 years of experience in a large cohort.
Cochlear Dead Regions in Sporadic Unilateral Vestibular Schwannomas Using the Threshold-Equalizing Noise Test
30-10-2019 – H Byun,YS Cho,SH Hong,IJ Moon
Background: Vestibular schwannoma (VS) is a benign intracranial neoplasm originating in the Schwann cells of the vestibular nerve. Despite its origin, the most common symptom is sensorineural hearing loss which is presented in more than 90% of patients. The underlying pathophysiology of this hearing loss has not been fully understood. Objective: To assess the in vivo function of cochlear inner hair cells and spiral ganglion neurons in VS, cochlear dead regions (DRs) were evaluated via the threshold-equalizing noise (TEN) test in untreated VS patients. Method: Untreated patients diagnosed with sporadic unilateral VS and normal contralesional hearing were enrolled from July 2011 to June 2016. Audiometric evaluation including TEN tests were performed. Based on the magnetic resonance findings, characteristics of individual tumors were assessed. Results: The average pure-tone threshold (word recognition score WRS) of 23 enrolled patients was 42.7 d
B (76.1%). Nineteen DRs (11.8% of 161 tested frequencies) were found in 8 patients (34.8% of enrolled cases). Among the intracanalicular (IAC) tumors, 6 out of 10 ears (60%) carried DRs, while 2 of 13 (15.4%) showed DRs among the cerebellopontine angle (CPA) lesions (p = 0.039). Pure-tone thresholds and WRS were not different between the two groups. Logistic regression analysis showed that the tumor location, IAC versus CPA, was significantly associated with DRs (p = 0.041, Nagelkerke R2 = 0.471), whereas age, sex, tumor size, distance from the tumor to the cochlea, T2-weighted hypointensity on the MRI and pure-tone thresholds showed no significance. Conclusions: Cochlear DRs are detected in hearing losses associated with unilateral sporadic VS using the TEN test. Individual DRs were detected variously in high, mid, or low frequencies. In our preliminary data, IAC tumors showed a higher number of DRs than CPA tumors despite similar average hearing thresholds. Further studies including longitudinal follow-up of hearing as well as change in DRs may provide useful information about VS patients.
Restoring the High-Frequency Dynamic Visual Acuity with a Vestibular Implant Prototype in Humans
29-10-2019 – D Starkov,N Guinand,F Lucieer,M Ranieri,S Cavuscens,M Pleshkov,JP Guyot,H Kingma,S Ramat,A Perez-Fornos,R van de Berg
Introduction: The vestibular implant could become a clinically useful device in the near future. This study investigated the feasibility of restoring the high-frequency dynamic visual acuity (DVA) with a vestibular implant, using the functional Head Impulse Test (f
HIT). Methods: A 72-year-old female, with bilateral vestibulopathy and fitted with a modified cochlear implant incorporating three vestibular electrodes (MED-EL, Innsbruck, Austria), was available for this study. Electrical stimulation was delivered with the electrode close to the lateral ampullary nerve in the left ear. The high-frequency DVA in the horizontal plane was tested with the f
HIT. After training, the patient underwent six trials of f
HIT, each with a different setting of the vestibular implant: (1) System OFF before stimulation; (2) System ON, baseline stimulation; (3) System ON, reversed stimulation; (4) System ON, positive stimulation; (5) System OFF, without delay after stimulation offset; and (6) System OFF, 25 min delay after stimulation offset. The percentage of correct f
HIT scores for right and left head impulses were compared between trials. Results: Vestibular implant stimulation improved the high-frequency DVA compared to no stimulation. This improvement was significant for “System ON, baseline stimulation” (p = 0.02) and “System ON, positive stimulation” (p #x3c; 0.001). f
HIT scores changed from 19 to 44% (no stimulation) to maximum 75–94% (System ON, positive stimulation). Conclusion: The vestibular implant seems capable of improving the high-frequency DVA. This functional benefit of the vestibular implant illustrates again the feasibility of this device for clinical use in the near future.
A Novel Pathogenic Variant in the CABP2 Gene Causes Severe Nonsyndromic Hearing Loss in a Consanguineous Iranian Family
29-10-2019 – M Koohiyan,MR Noori-Daloii,M Hashemzadeh-Chaleshtori,M Salehi,H Abtahi,MA Tabatabaiefar
Background and Objectives: Hereditary hearing loss (HL) can originate from mutations in one of many genes involved in the complex process of hearing. CABP2 mutations have been reported to cause moderate HL. Here, we report the whole exome sequencing (WES) of a proband presenting with prelingual, severe HL in an Iranian family. Methods: A comprehensive family history was obtained, and clinical evaluations and pedigree analysis were performed in the family with 2 affected members. After excluding mutations in the GJB2 gene and 7 other most common autosomal recessive nonsyndromic HL (ARNSHL) genes via Sanger sequencing and genetic linkage analysis in the family, WES was utilized to find the possible etiology of the disease. Results: WES results showed a novel rare variant (c.311G#x3e;A) in the CABP2gene.
This missense variant in the exon 4 of the CABP2gene meets the criteria of being pathogenic according to the American College of Medical Genetics and Genomics (ACMG) interpretation guidelines. Conclusions: Up to now, 3 mutations have been reported for the CABP2gene to cause moderate ARNSHL in different populations. Our results show that CABP2variantsalso cause severe ARNSHL, adding CABP2to the growing list of genes that exhibit phenotypic heterogeneity. Expanding our understanding of the mutational spectrum of HL genes is an important step in providing the correct clinical molecular interpretation and diagnosis for patients.
Are There Cochlear Dead Regions Involved in Hearing Loss after Cisplatin Ototoxicity?
29-10-2019 – C Schultz,PH Pecora Liberman,MV Schmidt Goffi-Gomez
Background: The most common complaint of patients affected by chemotherapy-induced hearing loss is difficulty understanding speech in noisy environments despite the use of hearing aids. Cochlear dead regions, those areas with damaged or absent inner hair cells and dendrites, may account for this type of hearing loss. However, it is unknown whether this condition is associated with cisplatin agents. Objective: The aim of this study was to determine whether cisplatin is associated with hearing loss and cochlear dead regions. Methods: This prospective cross-sectional study was conducted in patients participating in routine audiological monitoring during and after chemotherapy treatment. Adults undergoing audiological evaluation who had completed chemotherapy treatment were invited to participate. Patients were divided into 3 groups according to pure tone thresholds. Group 1 patients had thresholds over 70 d
B (HL) at 2,000 Hz and higher frequencies. Group 2 patients had thresholds below 70 d
B (HL) up to 2,000 Hz. Patients in the control group had normal thresholds at all frequencies. The threshold equalizing noise test (TENHL) was used to identify cochlear dead regions by repeating thresholds in the presence of TEN noise played from a compact disc. The presence of cochlear dead regions was established when the masked threshold was 10 d
B or greater above the TEN level and 10 d
B or greater above the absolute threshold at any frequency. Results: Twelve patients were included in study group 1, 10 patients in study group 2, and 7 patients in the control group. Cochlear dead regions were present in all patients with hearing loss and in none of the control group. For groups 1 and 2, mean differences between absolute and masked thresholds were 21 and 16 d
B at 500 Hz; 22 and 15 d
B at 1,000 Hz; 31 and 17 d
B at 2,000 Hz; 32 and 20 d
B at 3,000 Hz; and 31 and 21 d
B at 4,000 Hz, respectively. Nevertheless, analysis of variance testing with Bonferroni analysis showed a difference between groups 1 and 2 only at 2,000, 3,000, and 4,000 Hz. Conclusion: We found unresponsive or dead cochlear regions in patients who had undergone cisplatin chemotherapy even among patients with mild to moderate hearing loss.
Cochlear Place of Stimulation Is One Determinant of Cochlear Implant Sound Quality
29-10-2019 – MF Dorman,S Cook Natale,L Baxter,DM Zeitler,ML Carlson,JH Noble
Objective: Our aim was to determine the effect of acute changes in cochlear place of stimulation on cochlear implant (CI) sound quality. Design: In Experiment 1, 5 single-sided deaf (SSD) listeners fitted with a long (28-mm) electrode array were tested. Basal shifts in place of stimulation were implemented by turning off the most apical electrodes and reassigning the filters to more basal electrodes. In Experiment 2, 2 SSD patients fitted with a shorter (16.5-mm) electrode array were tested. Both basal and apical shifts in place of stimulation were implemented. The apical shifts were accomplished by current steering and creating a virtual place of stimulation more apical that that of the most apical electrode. Results: Listeners matched basal shifts by shifting, in the normal-hearing ear, the overall spectrum up in frequency and/or increasing voice pitch (F0). Listeners matched apical shifts by shifting down the overall frequency spectrum in the normal-hearing ear. Conclusion: One factor determining CI voice quality is the location of stimulation along the cochlear partition.
Influence of Cochlear Implantation on Postural Control and Risk of Falls
22-10-2019 – J Louza,C Rösel,R Gürkov,E Krause,F Ihler
Background: Cochlear implantation is an important method of hearing rehabilitation. Earlier studies have shown the influence of implantation on the vestibular system. However, until now, the effect of hearing rehabilitation with cochlear implants (CI) on postural control and body stability has not been sufficiently studied. Objective: To analyse the effect of hearing rehabilitation with activated CI and different sound inputs (music, speech text, and white noise) on postural control and risk of falls after implantation. Methods: This was a prospective clinical trial that included 33 adult patients with at least 6 months’ use of a CI (mean time after implantation = 23 months). All patients underwent a standard or geriatric (for patients #x3e;60 years) balancing deficit test protocol with a mobile posturography system (Verti
Guard®) in different situations (CI deactivated/activated and different sound inputs). As the main outcome measure, the risk of falls (%) after each protocol was calculated by evaluating body sway both forward to backward and side to side (°/s). Results: With the CI deactivated, the mean risk of falls was 45.5%. After activation of the CI, there was a small decrease in the mean risk of falls, but it was statistically significant. With an additional sound input (music or speech text) this decrease was more pronounced: 42.0 and 42.4%, respectively. This effect seems to be more pronounced in older patients. Regarding the individual patients, 72% had an improvement in the risk of falls with an activated CI, and 28% had a slight deterioration. An activated CI accompanied by sound input (music) further improved the individual risk of falls. Conclusions: Compared with prior research, this study found that the risk of falls after implantation decreased over a longer time period. Furthermore, the use of a CI and different sound inputs had a positive effect on postural control. These findings support the need for optimal hearing rehabilitation, especially in elderly patients. Although this effect is relatively small, it is important to consider for further studies that rehabilitation with CI may reduce the risk of falls. While the auditory system supposedly contributes to postural control only to a small degree and the mechanism is still poorly understood, further studies with bigger samples are warranted to clarify these effects.