Pediatric Benign Paroxysmal Positional Vertigo: Degree of Nystagmus and Concurrent Dizziness Differs from Adult BPPV.

Background: Benign paroxysmal positional vertigo (BPPV) is characterized by brief, intense episodes of vertigo triggered by abrupt changes in head position. It is generally accepted as being most common in adults, while it is regarded as rare in children. It is necessary to compare the disease between pediatric and adult patients for a better understanding of the disease's characteristics and its natural history. This study aimed to identify the clinical characteristics of BPPV in children and compare them with those of adult BPPV patients. Methods: All children ≤ 18 years old who were diagnosed with BPPV were selected by searching the electronic database of our hospital. Clinical features were identified by medical record review. For adult patients, we collected data from patients > 19 years of age. Results: A total of 30 pediatric (13.65 ± 4.15 years old) and 264 adult patients (60.86 ± 13.74 years old) were included in the study. Among pediatric patients, the lateral canals were involved in 80% and the posterior canals in 16.67%. In adult patients, the lateral and posterior canals were involved similarly (p = 0.007). The degree of nystagmus in pediatric patients was 6.82 ± 12.09, while in adults it was 15.58 ± 20.90 (p < 0.001). The concurrent dizziness disorder was higher in the pediatric group and recurrence was higher in the adult group. In the regression analysis, it was found that adult patients had a stronger nystagmus with a value of 6.206 deg/sec, and the risk of concurrent dizziness disorder was found to be 5.413 times higher in the pediatric group (p < 0.05). Conclusions: BPPV occurs in pediatric patients with lower prevalence, but it cannot be overlooked. In the pediatric group, a relatively high proportion of patients demonstrated lateral canal involvement, weaker nystagmus, and additional dizziness disorder.

Consensus Statements on the Definition, Classification, and Diagnostic Tests for Tinnitus: A Delphi Study Conducted by the Korean Tinnitus Study Group.

BACKGROUND: Tinnitus is a bothersome condition associated with various symptoms. However, the mechanisms of tinnitus are still uncertain, and a standardized assessment of the diagnostic criteria for tinnitus is required. We aimed to reach a consensus on diagnosing tinnitus with professional experts by conducting a Delphi study with systematic review of the literature. METHODS: Twenty-six experts in managing tinnitus in Korea were recruited, and a two-round modified Delphi study was performed online. The experts evaluated the level of agreement of potential criteria for tinnitus using a scale of 1-9. After the survey, a consensus meeting was held to establish agreement on the results obtained from the Delphi process. Consensus was defined when over 70% of the participants scored 7-9 (agreement) and fewer than 15% scored 1-3 (disagreement). To analyze the responses of the Delphi survey, the content validity ratio and Kendall's coefficient of concordance were evaluated. RESULTS: Consensus was reached for 22 of the 38 statements. For the definition of tinnitus, 10 out of 17 statements reached consensus, with three statements achieving complete agreement including; 1) Tinnitus is a conscious perception of an auditory sensation in the absence of a corresponding external stimulus, 2) Tinnitus can affect one's quality of life, and 3) Tinnitus can be associated with hearing disorders including sensorineural hearing loss, vestibular schwannoma, Meniere's disease, otosclerosis, and others. For the classification of tinnitus, 11 out of 18 statements reached consensus. The participants highly agreed with statements such as; 1) Vascular origin is expected in pulse-synchronous tinnitus, and 2) Tinnitus can be divided into acute or chronic tinnitus. Among three statements on the diagnostic tests for tinnitus only Statement 3, "There are no reliable biomarkers for sensory or emotional factors of tinnitus." reached consensus. All participants agreed to perform pure-tone audiometry and tinnitus questionnaires, including the Tinnitus Handicap Inventory and Tinnitus Questionnaire. CONCLUSION: We used a modified Delphi method to establish a consensus-based definition, a classification, and diagnostic tests for tinnitus. The expert panel reached agreement for several statements, with a high level of consensus. This may provide practical information for clinicians in managing tinnitus.

Factors Predicting Subjective Satisfaction for Successful Hearing Aid Adaptation.

(1) Background: For successful hearing aid (HA) use during daily life, an objective parameter reflecting the subjective satisfaction is required. We explored the aided hearing status, hearing in noise test (HINT) scores, and subjective outcomes to predict performance improvements in everyday living. (2) Methods: A total of 406 patients with hearing loss (HL) who were prescribed HAs were included and were divided into two groups according to the symmetricity of HL. The relationship between audiometric data and subjective questionnaires under unaided and aided (3 months) conditions were investigated. (3) Results: Patients with symmetric HL showed a significant HINT signal-to-noise ratio (SNR) change and significant increase in their subjective satisfaction questionnaire score under the bilateral HA condition. On the other hand, the HINT SNR change and subjective questionnaire score showed various significances according to the side of HA (better or worse hearing) in asymmetric HL HINT SNR and was significantly correlated with the subjective questionnaire score in symmetric HL patients and AHL patients with unilateral HA in their better ear. (4) Conclusions: The HINT SNR improvement after long-term HA use could be an effective tool for predicting the subjective satisfaction of HA use and HA validation.

Objective and subjective efficacy of hearing aids in patients with mild-to-moderate unilateral hearing loss: a prospective study.

PURPOSE: In patients with unilateral sensorineural hearing loss (USNHL), we explored both objective functional audiological gains and subjective satisfaction, indicating when a unilateral hearing aid is valuable. METHODS: Thirty-seven patients with mild-to-moderate USNHL (mean pure-tone thresholds between 25 and 70 dB) were prescribed unilateral hearing aids. Functional gain, the aided speech discrimination score (SDS), the Hearing in Noise Test (HINT) score, and the sound localization test score were collected, and a questionnaire (the Hearing Handicap Inventory for the Elderly, HHIE) completed after 1, 2, and 3 months of hearing aid use. We classified the participants as having 'no handicap' (HHIE < 17), 'mild-to-moderate handicap' (17-42), and 'significant handicap' (> 42). RESULTS: The decrease in handicap afforded by unilateral hearing aids was largest in the 'significant handicap' group (the HHIE total score fell from 59.1 to 37.2; P = 0.007). There were no between-group differences in either functional gain or the aided SDS. Only the 'significant handicap' group evidenced an improved HINT score; the composite signal-to-noise ratio (SNR) fell from - 1.5 to - 2.2 dB [S/N] (P = 0.023). The HHIE usefully indicated when a hearing aid alleviated the discomfort of USNHL; patients with unaided HHIE scores ≥ 20 evidenced significant decreases in the composite SNR (- 1.7 to - 2.0 dB [S/N]; P = 0.045). CONCLUSIONS: When considering whether to prescribe a unilateral hearing aid for patients with mild-to-moderate USNHL, it is helpful to use the HHIE to evaluate discomfort. If the total score is ≥ 20, a hearing aid is appropriate.

Abnormal Cholesterol Metabolism and Lysosomal Dysfunction Induce Age-Related Hearing Loss by Inhibiting mTORC1-TFEB-Dependent Autophagy.

Cholesterol is a risk factor for age-related hearing loss (ARHL). However, the effect of cholesterol on the organ of Corti during the onset of ARHL is unclear. We established a mouse model for the ARHL group (24 months, n = 12) and a young group (6 months, n = 12). Auditory thresholds were measured in both groups using auditory brainstem response (ABR) at frequencies of 8, 16, and 32 kHz. Subsequently, mice were sacrificed and subjected to histological analyses, including transmission electron microscopy (TEM), H&E, Sudan Black B (SBB), and Filipin staining, as well as biochemical assays such as IHC, enzymatic analysis, and immunoblotting. Additionally, mRNA extracted from both young and aged cochlea underwent RNA sequencing. To identify the mechanism, in vitro studies utilizing HEI-OC1 cells were also performed. RNA sequencing showed a positive correlation with increased expression of genes related to metabolic diseases, cholesterol homeostasis, and target of rapamycin complex 1 (mTORC1) signaling in the ARHL group as compared to the younger group. In addition, ARHL tissues exhibited increased cholesterol and lipofuscin aggregates in the organ of Corti, lateral walls, and spiral ganglion neurons. Autophagic flux was inhibited by the accumulation of damaged lysosomes and autolysosomes. Subsequently, we observed a decrease in the level of transcription factor EB (TFEB) protein, which regulates lysosomal biosynthesis and autophagy, together with increased mTORC1 activity in ARHL tissues. These changes in TFEB and mTORC1 expression were observed in a cholesterol-dependent manner. Treatment of ARHL mice with atorvastatin, a cholesterol synthesis inhibitor, delayed hearing loss by reducing the cholesterol level and maintaining lysosomal function and autophagy by inhibiting mTORC1 and activating TFEB. The above findings were confirmed using stress-induced premature senescent House Ear Institute organ of Corti 1 (HEI-OC1) cells. The findings implicate cholesterol in the pathogenesis of ARHL. We propose that atorvastatin could prevent ARHL by maintaining lysosomal function and autophagy by inhibiting mTORC1 and activating TFEB during the aging process.

Nasal Transcriptome and Epigenome Analysis Identifies the Pathogenic Features of Aspirin-Exacerbated Respiratory Disease.

Dysregulation of the arachidonic acid metabolic pathway is the most widely known pathomechanism of aspirin-exacerbated respiratory disease (AERD). This study aimed to perform integrative analysis of transcriptomic and epigenomic profiling with network analysis to determine the novel pathogenic features of AERD. Ten patients with asthma including 5 patients with AERD and another 5 patients with aspirin tolerant asthma (ATA) were enrolled. Nasal scraping was performed and nasal mucosa was used in omics profiling. Peripheral eosinophil counts, sputum eosinophil counts, fractional exhaled nitric oxide levels, and pulmonary function test results were evaluated. Differentially expressed genes (DEGs), differentially methylated probes (DMPs) and differentially correlated genes (DCGs) between patients with AERD and those with ATA were analyzed. Network analysis using ingenuity pathway analysis (IPA) was performed to determine the gene connection network and signaling pathways. In total, 1,736 DEGs, 1,401 DMPs, and 19 pairs for DCGs were identified. Among DCGs, genes related to vesicle transport (e.g., RAB3B and STX2) and sphingolipid dysregulation (e.g., SMPD3) were found to be hypo-methylated and up-regulated in AERD. Using the canonical pathway analysis of IPA with 78 asthma-related DEGs, signaling pathways of T helper cell differentiation/activation and Fcε receptor I were generated. Up-regulation of RORγt and FcER1A were noted in AERD. Gene expression levels of RAB3B, SYNE1, STX2, SMPD3 and RORγt were significantly associated with sputum eosinophil counts. Quantitative real-time polymerase chain reaction was performed and mRNA expression levels of STX2, SMPD3, RORγt, and FcER1A were significantly higher in AERD compared to ATA. Distinct pathogenic features were identified by using integrative multi-omics data analysis in patients with AERD.

Determination of Tympanostomy Tube Types for Otitis Media with Effusion in Patients with Cleft Palate: Comparison between Paparella Type 1 and Type 2 Tubes.

This study examined the effects of different types of tympanostomy tubes in pediatric patients undergoing cleft palate (CP) surgery in order to provide guidance for the proper insertion of tympanostomy tubes in the management of otitis media with effusion (OME). A total of 101 ears with middle ear effusion in 51 patients with CP were included in this study. Patients underwent palatoplasty and tympanostomy tube surgery at the same time. The type of tube inserted (Paparella type 1 or 2), the severity of CP, and types of palatoplasty surgeries were investigated. All patients were followed up for at least 6 months, and recurrence rates, complications, and reinsertion surgery were evaluated. The rate of OME recurrence after spontaneous tube extrusion was significantly higher in the type 1 group than in the type 2 group (44.3% vs. 19.4%, respectively, p = 0.016). Persistent eardrum perforation was more common in the type 2 group than in the type 1 group (41.9% vs. 12.9%, respectively, p = 0.001). The tube reinsertion rate was higher in the type 1 group than in the type 2 group (22.9% vs. 3.2%, respectively, p = 0.015). The tube reinsertion rate decreased to 8.6% in cases of palatoplasty with Sommerlad's technique, even with type 1 tube insertion, which was not significantly different from the reinsertion rate in the type 2 group (3.7%, p = 0.439). The Paparella type 1 tube would be a better choice in cases of palatoplasty performed using Sommerlad's technique, particularly considering the higher rate of persistent eardrum perforation after extrusion associated with the Paparella type 2 tube. Alternatively, a larger size type 2 tube may be considered in other surgeries to decrease the frequency of recurrence and tube reinsertion.

Which is Better for Ossiculoplasty Following Tympanomastoidectomy: Polycel® or Titanium?

OBJECTIVES: The purpose of this study was to compare the surgical outcomes of Polycel® and titanium in ossiculoplasty following tympanomastoidectomy (TM). METHODS: A total of 221 patients underwent ossiculoplasty following TM by a single surgeon using either Polycel® or titanium as prosthesis. Hearing was tested preoperatively and postoperatively at 6 months by pure-tone audiometry. Successful surgery was defined if postoperative air-bone gap (ABG) was <20 dB, the gain in air conduction (AC) hearing was >15 dB HL, or postoperative AC was <30 dB HL. Multiple linear regression was conducted to identify the factors associated with the surgical outcomes. RESULTS: In canal wall up mastoidectomy (CWUM), both Polycel® and titanium showed favorable successful rates if partial ossicular replacement prosthesis (PORP) was used (64.3% of Polycel® and 67.6% in titanium). If total ossicular replacement prosthesis (TORP) was used, both represented similar outcomes (54.5% of Polycel® and 75.0% in titanium). In canal wall down mastoidectomy (CWDM), significant ABG reductions were observed only in the titanium group (5.2 ± 14.7 dB of Polycel® [P = .083] and 7.0 ± 14.2 dB of titanium [P = .002] in PORP; 4.6 ± 13.5 dB of Polycel® [P = .097] and 9.5 ± 11.2 dB of titanium [P < .001] in TORP). In multivariate analysis, titanium had a positive effect on the reduction of postoperative AC thresholds (B: -4.772; 95% CI: -8.706--0.838). CONCLUSIONS: Both Polycel® and titanium showed favorable surgical outcomes for ossiculoplasty following CWUM. Titanium prosthesis is recommended for surgery after CWDM.

Dexamethasone Effect on Sudden Hearing Loss is Validated in Stress-induced Animal Models: Hypothetical Study.

BACKGROUND: Stress could be a contributing cause of sudden hearing loss. This study intended to develop an animal model of stress-induced sudden hearing loss and to evaluate the effects of dexamethasone. METHODS: Two stress models (I and II) for rats were designed using various stressors and modified by adjusting the stress protocol to increase the threshold significantly. For the stress model with a significant increase in threshold after stress exposure, changes in cortisol levels according to stress exposure were measured. The threshold shift and the change in the cellular structure associated with stress exposure and dexamethasone administration were analyzed. RESULTS: While hearing thresholds increased only at 16 kHz in rats of stress model I (n=10), the thresholds increased at 16 and 32 kHz in rats of stress model II (n=16). Cortisol level increased after stress exposure (P = .015) in stress model II. Among stress model II rats (stress only and stress+dexamethasone groups), the threshold shift at 16 kHz significantly decreased 1 day after dexamethasone injection in the stress+dexamethasone group (n=8). Histologically, the cochlear cellularity of the stress+dexamethasone group was more compact than that of the stressonly group (n=8). CONCLUSION: Our preliminary study presented the development of an animal model of stress-induced sudden hearing loss and the positive results of steroids in terms of hearing recovery.

Preliminary study to determine an optimal mode for favorable residual hearing at low frequencies: Full electrical stimulation, electric acoustic stimulation, and electrical complement.

Objective: In this prospective study, each subject experienced three modes electric acoustic stimulation (EAS), full electrical stimulation (FES), and electrical complement (EC), and the performance of each mode and subject preference were evaluated. Methods: Eight ears (seven patients) with successfully preserved residual hearing after cochlear implantation (CI) were included. EAS, FES, and EC programs were set up on each patient's device, and each mode was used for at least 1 h per day for a month. The Speech Intelligibility test, the Speech, Spatial and Qualities of Hearing Scale, and the Hearing in Noise test (HINT) results in each stimulation mode. Results: The mean monosyllabic word score (EAS: 90.3 ± 4.0; FES: 81.2 ± 16.1) and the mean sentence score (EAS: 98.3 ± 1.7; FES: 95.0 ± 3.0) were significantly higher in the EAS mode than in the FES mode. The mean bisyllabic word score (EAS: 95.6 ± 5.6; EC: 90.1 ± 5.6) was higher in the EAS mode than in the EC mode. In HINT, the signal-to-noise ratios under the noise front (EAS: 4.7 ± 2.5; FES: 7.9 ± 4.4) and noise composite conditions (EAS: 4.2 ± 2.7; FES: 6.6 ± 4.0) were significantly smaller in the EAS mode than in the FES mode. After trials of the three modes, five subjects preferred EAS, one preferred EC, and two preferred FES. Conclusion: Among the three stimulation modes, EAS produced slightly better results, and subjects generally preferred EAS (five of seven patients, 71.4%). The use of hearing aids before CI was considered an important factor in mode preference. FES may be preferred when CI was performed at a young age and subjects had little experience with hearing aids. However, adults may prefer EC over EAS if there was little or no hearing-aid use before CI.

Effect of statin on age-related hearing loss via drug repurposing.

Hearing loss in the elderly cause communication difficulties, decreased quality of life, isolation, loneliness and frustration. The aim of our study was to investigate the effect of drug repurposing candidates in aging mouse. The selected candidate drugs for age-related hearing loss (ARHL) included atorvastatin (AS) and sarpogrelate. Monotherapy or fixed dose combination (FDC) products were administered via oral gavage for 6 consecutive months. Auditory outcomes showed significant hearing preservation in AS-treated aging mice compared to aging control, especially in the early stages of ARHL in both 8 and 16 kHz frequencies. However, none of the FDC products were able to prevent ARHL regardless of AS involvement. In aging mice, damage and dysfunction of mitochondria was noted as well as reactive oxygen species overproduction leading to oxidative stress and intrinsic apoptosis. These processes of ARHL were significantly prevented with administration of AS. Normal structures of mitochondria were maintained, and antioxidant activity were proceeded by activation of HSF1/Sirt1 pathway. Our study suggests that AS is a promising drug repurposing candidate to delay the progression of ARHL.

Development of Intracorporeal Differentiation of Stem Cells to Induce One-Step Mastoid Bone Reconstruction during Otitis Media Surgeries.

Mastoidectomy is a surgical procedure for the treatment of chronic otitis media. This study investigated the ability of rat stromal vascular fraction cells (rSVF) in combination with polycaprolactone (PCL) scaffolds and osteogenic differentiation-enhancing blood products to promote the regeneration of mastoid bone defect. Twenty male Sprague Dawley rats were randomly divided according to obliteration materials: (1) control, (2) PCL scaffold only, (3) rSVFs + PCL, (4) rSVFs + PCL + platelet-rich plasma, and (5) rSVFs + PCL + whole plasma (WP). At 7 months after transplantation, the rSVFs + PCL + WP group showed remarkable new bone formation in the mastoid. These results indicate that SVFs, PCL scaffolds, and blood products accelerate bone regeneration for mastoid reconstruction. Autologous SVF cells with PCL scaffolds and autologous blood products are promising composites for mastoid reconstruction which can be easily harvested after mastoidectomy. With this approach, the reconstruction of mastoid bone defects can be performed right after mastoidectomy as a one-step procedure which can offer efficiency in the clinical field.

Comparison of surgical results between 'atticosinuplasty' and canal wall up mastoidectomy for early-stage cholesteatoma.

BACKGROUND: We devised a surgical technique called 'atticosinuplasty' (AS) for the treatment of early-stage cholesteatoma. OBJECTIVE: This study analyzed the adequacy and applicability of AS compared to canal wall-up mastoidectomy (CWU) in patients treated for early-stage cholesteatoma. MATERIALS AND METHODS: A total of 187 patients with either AS (n = 89) or CWU (n = 98) were compared in terms of postoperative hearing outcome, recurrence and re-operation rate, and radiologic outcome. RESULTS: Hearing gain was significant in the AS group (p < 0.001) but not in the CWU group. Air conduction change, air-bone gap (ABG) change, and ABG closure did not significantly differ between the two groups. The frequencies of cholesteatoma recurrence and revision ossiculoplasty were also similar. Of the 32 patients in the AS group with only attic/sinus involvement preoperatively, 20 (62.5%) showed no haziness and 6 (18.8%) had haziness extending to the mastoid postoperatively. Among the 67 patients in the CWU group who had haziness extending to the mastoid preoperatively, in 54 (80.6%) there was no change postoperatively. CONCLUSIONS AND SIGNIFICANCE: AS is a surgical technique worth trying in patients with early stage of attic/sinus cholesteatoma in terms of the rate of recurrence and hearing improvement.

Effect of Age at Cochlear Implantation in Educational Placement and Peer Relationships.

OBJECTIVES: The education and school life of children who have undergone cochlear implantation (CI) is very important and should be monitored continuously. This study assessed auditory performance in children with cochlear implants over time, along with educational placement and peer relationship, and compared the results based on the age at CI and the presence of additional disabilities. DESIGN: In total, 77 children who had undergone CI at the Hearing Center in Ajou University Hospital at less than 10 years old and who were presently attending school or had already graduated from school within 3 years were enrolled in this study. All children had congenital bilateral severe or profound hearing loss at the diagnosis. They were classified based on the age at which they received CI: the "early-implanted group," younger than 3.5 years (n = 38), and the "late-implanted group," between 3.5 and 10 years old (n = 39). RESULTS: The early-implanted group had worse short-term auditory performance than the late group, but after 2 years of the implant use, auditory performance was similar in both groups. The early and late groups did not differ significantly in terms of the proportions of children who were enrolled in a regular school (94.7% and 89.7%, respectively). However, the early-implanted group had a larger proportion of children who were enrolled in a regular school without additional needs (73.0%), compared with the late group (48.6%) (p = .034). Children with multiple disabilities showed poorer performance (word score of 57.7% and sentence score of 44.7%) than children with hearing disability only (91.8% and 87.2%, respectively), which affected full-time enrollment in regular schools. With regard to peer relationships, 19.0% of children in the early-implanted group required close observation and assistance, and 9.5% even required help and counseling. Children who underwent early CI had a high tendency toward social restraint, apathy, and over-commitment. No correlations were observed between audiological factors and the aspects of peer relationships assessed in this study. CONCLUSIONS: Early CI and the absence of other disabilities were the two main factors that increased the likelihood of full-time enrollment in mainstream classes at regular schools. Nevertheless, many children who underwent earlier CI still encountered difficulties in peer relationships.

BCL2 Interacting Protein 3-like/NIX-mediated Mitophagy Plays an Important Role in the Process of Age-related Hearing Loss.

Clearance of dysfunctional mitochondria via mitophagy is essential for cell survival and cochlear functions. However, it is not clear which genes are significantly involved in this process. Here, we investigated the changes in mitophagy and mitophagy-associated genes in mouse auditory cells to determine a possible correlation between mitophagy and age-related hearing loss (ARHL). Here, we show that most transcripts associated with mitophagy were downregulated in an age-dependent manner. We identified one significant differentially expressed gene associated with mitophagy, BCL2 interacting protein 3-like (BNIP3L)/NIX. Mitophagy-inhibited cells with BNIP3L/NIX knockdown showed hyperresponsiveness to oxidative stress resulting in cell senescence with increased levels of TOMM20 and LC3B. Overexpression of BNIP3L/NIX promotes the degradation of TOMM20 and LC3B during premature cell senescence. In conclusion, BNIP3L/NIX may play an important role in mitochondria degradation maintaining cochlear cell homeostasis during the aging process of hearing.

Changes in Vestibular Symptoms and Function After Cochlear Implantation: Relevant Factors and Correlations With Residual Hearing.

OBJECTIVES: The aim of this study was to evaluate vestibular function loss after cochlear implantation (CI) and the relationship between vestibular function and hearing changes. METHODS: Seventy-five patients with CI were enrolled and divided into those with normal preoperative caloric function (group I) and those with a normal preoperative waveform in cervical vestibular evoked myogenic potential (c-VEMP) testing (group II). The relationship between hearing and changes in the vestibular system was analyzed preoperatively and at 3 and 6 months postoperatively. RESULTS: In group I, unilateral weakness on the implanted side was detected in five (7.7%) and eight (12.3%) patients at 3 and 6 months post-CI, respectively. By 3 months post-CI, the total slow-phase velocity (SPV; warm and cold stimulations) was significantly different between the implanted and non-implanted sides (P=0.011), and the shift in total SPV from pre- to post-CI was significantly correlated with the average hearing threshold at 6 months post-CI. In group II, an abnormal c-VEMP was detected on the implanted side in six patients (16.2%) at 3 months post-CI, and in six patients (16.2%) at 6 months post-CI. Significant changes were noticed in the P1 and N1 amplitude at 3 months postCI (P=0.027 and P=0.019, respectively). CONCLUSION: Vestibular function and residual hearing function should be afforded equal and simultaneous consideration in terms of preservation.

Cochlear Implantation via the Transmeatal Approach in an Adolescent with Hunter Syndrome-Type II Mucopolysaccharidosis.

Type II mucopolysaccharidosis (MPS II) commonly known as Hunter syndrome, is a rare X-linked lysosomal storage disorder caused by iduronate-2-sulfatase deficiency, which in turn causes otorhinolaryngological manifestations, including sensorineural hearing loss (SNHL). Previously, the median survival age of patients with MPS was approximately 13.4 years. However, in the era of enzyme replacement therapy and other multidisciplinary care modalities, the life expectancy has increased. Herein, we report a rare case of an adolescent with MPS II who underwent SNHL treatment with cochlear implantation (CI). Based on unexpected findings of mastoid emissary veins and overgrowth of the vessels around the temporal bone, CI was performed using the transmeatal approach instead of the conventional transmastoid method, to avoid damage to the vessels. The average hearing threshold after CI was 35 dB and no surgical complications were encountered. Adolescent MPS II may present vessel abnormalities, which can reduce the success rate of surgery. In patients with MPS II with SNHL, CI should be performed under careful monitoring of vessel overgrowth. Moreover, with regard to feasibility of CI in adolescent patients with MPS II with SNHL, surgical techniques such as the transmeatal approach should be selected based on adequate assessment of the case.

A New CT Parameter for Predicting Residual Hearing Preservation in Cochlear Implantation: The "Basal Turn-Facial Ridge Angle".

OBJECTIVES: We suggest a simple measurement, called the "basal turn-facial ridge (BT-FR) angle," for determining the electrode insertion axis using preoperative temporal bone computed tomography (CT) to predict hearing preservation (HP) in cochlear implantation (CI). STUDY DESIGN: Retrospective chart review. SETTING: Tertiary referral center. PATIENTS: Eighty-two ears that underwent CI between 2010 and 2018 were included. Ears with preoperative thresholds less than or equal to 80 dB HL at 125, 250, and 500 Hz were enrolled and grouped using the criteria of Skarzynski et al.: Group 1, complete or partial HP; Group 2, minimal HP or complete hearing loss. INTERVENTION: All subjects underwent CI with soft surgery techniques through the round window approach. MAIN OUTCOME MEASURES: The BT-FR angle is the angle between the basal turn line (BT-line), which is a straight line passing through the center of the longitudinal axis of the BT, and the facial ridge line, which is a straight line running from the endpoint of the BT-line to a point just above the facial ridge. RESULTS: The BT-FR angle was 2.5 ±â€Š2.9 degrees in Group 1 and -0.3 ±â€Š2.7 degrees in Group 2 (p = 0.003). The angle and hearing loss showed a significant negative correlation (r = -0.401, p = 0.002). In multiple linear regression, "age at operation" (ß coefficient 0.260; p = 0.001) and the "BT-FR angle" (-1.967; p = 0.001) were significant variables affecting the degree of residual hearing loss. CONCLUSIONS: The BT-FR angle, which can be measured simply, may be useful to predict residual HP after CI.

Atorvastatin prevents hearing impairment in the presence of hyperlipidemia.

It is known that hyperlipidemia is a risk factor for sensorineural hearing loss. However, the biological mechanisms underlying hyperlipidemia and hearing impairment have not been completely elucidated in the cochlea. Based on our previous study of human subjects, elderly people taking drugs for hyperlipidemia showed better hearing than those not taking any medications. We hypothesized that drugs for hyperlipidemia, such as statins, may have the potential to prevent hearing impairment. The aim of this study was to investigate the correlation between hyperlipidemia and hearing impairment and the hearing preservation effect of atorvastatin using a hyperlipidemic mouse model with diet-induced obesity (DIO). Here, we demonstrate that DIO mice had a significant hearing impairment as well as increased levels of reactive oxygen species (ROS) and hair cell death due to reduced levels of pAKT and superoxide dismutase 2 (SOD2). However, these changes were significantly prevented by atorvastatin. Oxidative stress-induced intrinsic apoptosis was decreased by the high expression of Nrf2 and antioxidant genes, which improved mitochondrial function and ROS via activation of the PI3K-pAKT pathway by atorvastatin. Therefore, atorvastatin has the potential to prevent hearing impairment via redox balance in the presence of hyperlipidemia.

Suppressed expression of LDHB promotes age-related hearing loss via aerobic glycolysis.

Age-dependent decrease of mitochondrial energy production and cellular redox imbalance play significant roles in age-related hearing loss (ARHL). Lactate dehydrogenase B (LDHB) is a key glycolytic enzyme that catalyzes the interconversion of pyruvate and lactate. LDH activity and isoenzyme patterns are known to be changed with aging, but the role of LDHB in ARHL has not been studied yet. Here, we found that LDHB knockout mice showed hearing loss at high frequencies, which is the typical feature of ARHL. LDHB knockdown caused downregulation of mitochondrial functions in auditory cell line, University of Bristol/organ of Corti 1 (UB/OC1) with decreased NAD+ and increased hypoxia inducing factor-1α. LDHB knockdown also enhanced the death of UB/OC1 cells with ototoxic gentamicin treatment. On the contrary, the induction of LDHB expression caused enhanced mitochondrial functions, including changes in mitochondrial respiratory subunits, mitochondrial membrane potentials, ATP, and the NAD+/NADH ratio. Thus, we concluded that suppression of LDHB activity may be closely related with the early onset or progression of ARHL.