Audiologic Status of Children with Confirmed Cytomegalovirus Infection: a Case Series

Background: Congenital cytomegalovirus (CMV) infection is the most common non-genetic cause of sensorineural hearing loss (SHNL) in children. Only about 10% to 15% of children with congenital CMV are symptomatic, and most are not diagnosed at birth. About 7% to 15% of clinically asymptomatic patients may develop later complications, including SNHL, which is the most common sequela in clinically asymptomatic patients. In this study, hearing status was investigated in children with confirmed CMV infection and neonatal hearing screening (NHS) histories were reviewed to explore hearing loss caused by CMV. Methods: The medical records of 58 children who were diagnosed with confirmed CMV infection were reviewed for clinical symptoms and signs of CMV infection. Hearing status was evaluated with age-appropriate audiological test batteries. Results: A total of 58 children (M:F = 32:26 patients; age at study: mean, 5.62 years, range, 1-10 years) were diagnosed serologically with CMV infection (14 patients, 21.1%), or diagnosed via PCR of serum (5, 7.9%) and/or PCR from urine (19, 26.8%). Hearing loss was confirmed in 11 children (19.0%), being bilateral in 6 (54.5%), and unilateral in 5 (45.5%). Note that 7 of 17 ears with hearing loss passed NHS and were diagnosed only after re-evaluation when CMV infection was identified. Conclusion: Hearing loss is a serious complication of CMV infection in children. Our results highlight the importance of timely audiological evaluation in children with clinically symptomatic CMV infection even if they pass NHS.ope

Limitation of Conventional Audiometry in Identifying Hidden Hearing Loss in Acute Noise Exposure

Purpose: The concept of hidden hearing loss can explain the discrepancy between a listener's perception of hearing ability and hearing evaluation using pure tone audiograms. This study investigated the utility of the suprathreshold auditory brainstem response (ABR) for the evaluation of hidden hearing loss in noise-exposed ear with normal audiograms. Materials and methods: A total of 15 patients (24 ears) with normal auditory thresholds and normal distortion product otoacoustic emissions were included in a retrospective analysis of medical records of 80 patients presenting with histories of acute noise exposure. The control group included 12 subjects (24 ears) with normal audiograms and no history of noise exposure. Pure tone audiometry and suprathreshold ABR testing at 90 dB peSPL were performed. The amplitudes and latencies of ABR waves I and V were compared between the noise-exposed and control groups. Results: We found no significant difference in the wave I or V amplitude, or the wave I/V ratio, between the two groups. The latencies of ABR wave I, V, and I-V interpeak interval were compared, and no significant intergroup difference was observed. Conclusion: The results suggest that either hidden hearing loss may not be significant in this cohort of patients with acute noise exposure history, or the possible damage by noise exposure is not reflected in the ABRs. Further studies are needed to inquire about the role of ABR in identification of hidden hearing loss.ope

Relationship of Vertigo and Postural Instability in Patients With Vestibular Schwannoma

OBJECTIVES: Growth of vestibular schwannomas (VS) causes progressive vestibular symptoms and postural instability. Since the tumor grows slowly, compensation of decaying vestibular input may decrease subjective symptoms of dizziness. This study aims to estimate the relationship of subjective vestibular symptoms and objective postural instability in patients with VS. METHODS: A retrospective review of 18 patients newly diagnosed with VS and with subjective vertigo symptoms was performed. The results of vestibular function tests including the sensory organization test (SOT) using computerized dynamic posturography, caloric test, and self-report measures of subjective dizziness handicap (Dizziness Handicap Inventory) and visual analogue scale were compared according to the onset of vertigo symptoms. RESULTS: In VS patients, SOT showed decreased equilibrium score for all vestibular function related conditions, condition (C) 5 and 6, and composite (COMP) score. COMP scores were not correlated with visual analogue scale or Dizziness Handicap Inventory scores. Acute onset group included six patients and insidious onset group, 12 patients. Equilibrium scores for C5 and C6, and COMP scores were lower for insidious onset group, but the difference was not statistically significant. CONCLUSION: Our findings confirmed postural instability is prevalent in VS patients. SOT parameters did not differ significantly between acute onset and insidious onset groups, but increased tumor size and canal weakness were noted in the insidious onset group. Clinicians should consider that postural instability is likely present even in patients who do not complain of acute vertigo, and appropriate counseling should be discussed with the patients.ope

Importance of High-Frequency Vestibular Function in the Prognosis of Bilateral Vestibulopathy

Objectives: The aim of this study was to investigate whether preserved vestibular function in the high-frequency range influences the prognosis of patients with bilateral vestibulopathy (BVP) after vestibular rehabilitation. Methods: Twenty-four patients followed up with vestibular rehabilitation were recruited. The enrolled patients were divided into two groups according to the preservation of the high-frequency vestibulo-ocular reflex (VOR) based on the video head impulse test (vHIT). The results of computerized dynamic posturography and the Dizziness Handicap Inventory (DHI) survey collected at baseline and at the 6-month follow-up after vestibular rehabilitation therapy were analyzed. Results: Both groups showed significantly increased composite and DHI scores after follow-up with vestibular rehabilitation. The group with preserved high-frequency VOR showed a better composite score (p=0.064) and vestibular score (p= 0.008) than the group with lost high-frequency VOR at the 6-month follow up. The DHI score significantly decreased only in the group with lost high-frequency VOR (p=0.047). Among the three vestibular function tests (caloric test, rotary chair test, and vHIT) used to diagnose BVP, only vHIT showed a significant correlation (p=0.015) with a favorable prognosis (composite score ≥70). Conclusion: Better treatment outcomes are likely in patients with BVP with preserved vestibular function in response to high-frequency stimulation, as measured by the vHIT.ope

Prognostic Factors Affecting Surgical Outcomes in Squamous Cell Carcinoma of External Auditory Canal

OBJECTIVES: Carcinomas of the external auditory canal (EAC) are rare, and management remains challenging. Previous studies seeking prognostic factors for EAC cancers included cancers other than carcinomas. In this study, we analyzed the treatment outcomes of, prognostic factors for, and survival rates associated with specifically squamous cell carcinoma (SCC) of the EAC. METHODS: A retrospective review of 26 consecutive patients diagnosed with SCCs of the EAC in a 10-year period was performed in terms of clinical presentation, stage, choice of surgical procedure, and adjunct therapy. Overall survival (OS) and recurrence-free survival (RFS) were calculated and univariate analysis of prognostic factors was performed. RESULTS: The median age of the 26 patients with SCCs of the EAC was 63 years (range, 40 to 72 years), and 16 males and 10 females were included. According to the modified University of Pittsburgh staging system, the T stages were T1 in 11, T2 in six, T3 in four, and T4 in five cases. The surgical procedures employed were wide excision in three cases, lateral temporal bone resection (LTBR) in 17, and extended LTBR in four, and subtotal temporal bone resection in two. Two patients underwent neoadjuvant chemotherapy, and two underwent adjuvant chemotherapy. One patient received preoperative radiation therapy, and eleven received postoperative radiation therapy. Of the possibly prognostic factors examined, advanced preoperative T stage and advanced overall stage were significant predictors of RFS, but not of OS. CONCLUSION: The advanced T stage and overall stage were associated with decreased survival after surgical treatment in patients with SCC of the EAC, highlighting the importance of clinical vigilance and early detection.ope

Relationship between Hearing Loss and Dementia Differs According to the Underlying Mechanism

Background and purpose: The associations between hearing loss (HL) and the mechanisms underlying cognitive impairment (CI) remain unclear. We evaluated the effects of clinical factors, vascular magnetic resonance imaging (MRI) markers, and CI mechanisms on HL. Methods: In total, 112 patients with CI (59% demented) and subjective HL prospectively underwent MRI, amyloid positron-emission tomography (PET), hearing evaluations, and neuropsychological tests including a language comprehension test. Patients were categorized into pure-Alzheimer's disease-related CI (ADCI), pure-Lewy-body disease-related CI (LBCI), mixed-ADCI/LBCI, and non-ADCI/LBCI groups based on clinical features and PET biomarkers. Results: The risk of peripheral HL [defined as a pure-tone average (PTA) threshold >40 dB] was higher in the pure-LBCI group than in the pure-ADCI and mixed-ADCI/LBCI groups, and lower in the presence of ADCI. The non-ADCI/LBCI group had the most-severe vascular MRI markers and showed a higher risk of peripheral HL than did the pure-ADCI and mixed-ADCI/LBCI groups. While the pure-LBCI group had a higher risk of comprehension dysfunction than the pure-ADCI group regardless of the PTA and the score on the Korean version of the Mini Mental State Examination (K-MMSE), those in the pure-LBCI group even with a better K-MMSE score had a risk of comprehension dysfunction comparable to that in the mixed-ADCI/LBCI group due to a worse PTA. Conclusions: Peripheral HL could be associated with the absence of significant β-amyloid deposition in patients with CI and characteristic of the pure-LBCI and non-ADCI/LBCI groups.ope

Pathophysiologic Findings in the Human Endolymphatic Sac in Endolymphatic Hydrops: Functional and Molecular Evidence

BACKGROUND: The endolymphatic sac (ES) is a cystic structure situated on the posterior fossa dura and is connected to the luminal space of the vestibular organ through the endolymphatic duct, which branches into the utricular and saccular ducts. Unlike the cochlea and vestibule, the ES does not contain sensory epithelium in its luminal space, and a single layer of epithelial cells line the luminal surface area. The ES in the inner ear is thought to play a role in the regulation of inner ear homeostasis, fluid volume, and immune reaction. If these functions of the ES are disrupted, dysfunction of the inner ear may develop. The most well-known pathology arising from dysfunction of the ES is endolymphatic hydrops, characterized by an enlarged endolymphatic space due to the accumulation of excessive endolymphatic fluid. Although, molecular identities and functional evidence for the roles were identified in animal studies, basic studies of the human ES are relatively uncommon compared with those using animal tissues, because of limited opportunity to harvest the human ES. METHODS: In this study, molecular and functional evidence for the role of the human ES in the development of endolymphatic hydrops are reviewed. RESULTS AND CONCLUSIONS: Although evidence is insufficient, studies using the human ES have mostly produced findings similar to those of animal studies. This review may provide a basis for planning further studies to investigate the pathophysiology of disorders with the finding of endolymphatic hydrops.restrictio

Meta-analysis of Delayed Facial Palsy Following Middle Ear Surgery

OBJECTIVE: Delayed facial palsy has been reported following various types of otologic surgery. However, the exact characteristics of this disease have not been fully elucidated because of its low incidence. This study analyzed case series studies on delayed facial palsy to increase the sample size and outline credible disease characteristics. DATA SOURCES: PubMed, Embase, and Cochrane Library databases were searched on October 10, 2018. STUDY SELECTION: Delayed facial palsy case series covered in English in which the intervention was typical tympanoplasty, mastoidectomy, stapedectomy, or cochlear implantation including a statement of sample size. DATA EXTRACTION: Evaluated according to the Joanna Briggs Institute Critical Appraisal Checklist for Case Series. DATA SYNTHESIS: Fourteen case series studies were included. Incidence rate, onset time, prognosis were evaluated with meta-analysis. Etiology and treatment were discussed with systematic review. CONCLUSIONS: The overall incidence rate of delayed facial palsy after middle ear surgery was 0.65%; however, it differed depending on the type of surgery. The mean onset time of facial palsy was 8.47 ± 3.98 days after surgery, and 95.3% of the patients completely recovered. The disease seems to have multiple etiologies. Facial palsy occurring 2 to 20 days after surgery is suggested to be considered delayed facial palsy.restrictio

Momentum effects based on style comovement

학위논문(석사) - 한국과학기술원 : 경영공학부, 2014.2, [ iii, 42 p. ]한국 주식시장에는 개별 종목의 모멘텀 효과로 향후의 초과 수익률을 올릴 수 없다는 것이 정설이다. 하지만, 본 연구에는 스타일 단위의 모멘텀 효과가 존재한다는 것과 개별 종목의 스타일 동조화 경향 (Style comovement) 이 평균 회귀 성질 (Mean-reverting property) 을 가진다는 것을 이용하여 주식시장에 있는 종목들 중 모멘텀을 가질 종목들을 선별해낼 수 있음으로 보이고, 이를 이용하여 수익성 있는 투자 전략을 수립하는 것이 가능함을 확인한다.한국과학기술원 : 경영공학부

Clinical Experience of Vibroplasty With Direct Coupling to the Oval Window Without Use of a Coupler

Objectives/hypothesis: To investigate the efficacy of direct implantation of a Vibrant Soundbridge (VSB) implant in the oval window (OW) without the use of an OW coupler in patients with severe mixed hearing loss. Study design: Retrospective chart review METHODS: A total of 62 patients underwent VSB implantation between July 2016 and December 2018 at Severance Hospital in Seoul, South Korea. Among them, eight patients (nine ears) with moderate-to-severe mixed hearing loss were implanted with a VSB directly in the OW. A floating mass transducer (FMT) was attached to the stapes footplate and covered with tragal cartilage. The outcomes were evaluated using pure-tone audiogram and speech audiogram preoperatively and postoperatively. Word recognition score (WRS; % correct) were measured at the most comfortable loudness (MCL) level to evaluate speech perception. Results: All cases posed difficulty with round window vibroplasty during surgery, and eventually, an FMT was appropriately placed in the OW without a coupler. Preoperative and postoperative bone conduction thresholds were not different. VSB-aided threshold improved in terms of functional and effective gains. Interestingly, four cases showed improved air conduction thresholds without the use of a VSB. In addition, MCL level with a VSB was significantly lower than that with a hearing aid, and VSB-aided WRS improved over time. Conclusions: Direct implantation of a VSB in the OW without the use of a coupler showed favorable hearing outcomes, and the OW vibroplasty was safe. Direct OW vibroplasty without a coupler is a reliable procedure and can be a good option for hearing rehabilitation in patients with severe mixed hearing loss. Level of evidence: 4 Laryngoscope, 2020.restrictio