Three-Dimensional Distribution of Cochlear Macrophages in the Lateral Wall of Cleared Cochlea

Objectives: Resident macrophages are well known to be present in the cochlea, but the exact patterns thereof in spiral ligaments have not been discussed in previous studies. We sought to document the distribution of macrophages in intact cochleae using three-dimensional imaging. Methods: Cochleae were obtained from C-X3-C motif chemokine receptor 1+/GFP mice, and organ clearing was performed. Three-dimensional images of cleared intact cochleae were reconstructed using two-photon microscopy. The locations of individual macrophages were investigated using 100-μm stacked images to reduce bias. Cochlear inflammation was then induced by lipopolysaccharide (LPS) inoculation into the middle ear through the tympanic membrane. Four days after inoculation, three-dimensional images were obtained. Results: Macrophages were scarce in areas adjacent to the stria vascularis, particularly the area just beneath it even though many have suspected macrophages to be abundant in this area. This finding remained consistent upon LPS-induced cochlear inflammation, despite a significant increase in the number of macrophages, compared to non-treated cochlea. Conclusion: Resident macrophages in spiral ligaments are scarce in areas adjacent to the stria vascularis.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

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

고주파 스퍼터링법으로 증착한 ZnO 박막의 응력 형성과 박막 특성에 미치는 영향

학위논문(석사)--서울대학교 대학원 :무기재료공학과,2000.Maste

Concurrent Presence of Vestibulae Schwannoma and Adenoma

Vestibular schwannoma and pituitary adenoma are intracranial tumors with different histological characteristics, and coexistence of these tumors is very rare. The concurrent presence case of these tumors firstly reported in the literature at 1985 by Gorman. Over the years, there have been a few case-reports for concurrent presence of these tumors. However, the association between these tumors have not been established. Here, we report a 53 years-old male patient case who was diagnosed with vestibular schwannoma and coexistence of pituitary adenoma.ope

Is Early Progression to Bilateral Involvement in Menière's Disease a Poor Prognostic Indicator?

OBJECTIVE: To investigate differences in the clinical features of bilateral Menière's disease (BMD) with early and late bilateral involvement. STUDY DESIGN: A retrospective case-comparison study. SETTING: Tertiary referral center. PATIENTS: In total, 25 patients with definite BMD were enrolled. Patients with bilateral involvement with a transition interval shorter than 1 month were considered to have synchronous BMD, whereas the others had metachronous BMD. INTERVENTIONS: We investigated differences in prognosis as defined by changes in the number of vertigo attacks after treatment, demographics, comorbidities, and inner ear function according to the transition interval from unilateral to bilateral involvement. MAIN OUTCOME MEASURE: We investigated other appropriate cut-off values in the interval from first- to second-ear involvement to predict poor prognosis. RESULTS: Receiver operating characteristic curve analysis revealed that a cut-off value of  0.05). None of the patients exhibited systemic autoimmune disease. CONCLUSION: BMD with early bilateral progression exhibited poorer prognosis compared with late bilateral progression.restrictio

Effects of Saccular Function on Recovery of Subjective Dizziness After Vestibular Rehabilitation

OBJECTIVE: We attempted to investigate whether the integrity of saccular function influences the severity of subjective dizziness after vestibular rehabilitation in vestibular neuritis. STUDY DESIGN: Retrospective analysis. SETTING: Tertiary referral center. PATIENTS: Forty-six patients with acute unilateral vestibular neuritis were included. INTERVENTIONS: Diagnostic, therapeutic, and rehabilitative. MAIN OUTCOME MEASURES: All the patients completed vestibular rehabilitation therapy until their computerized dynamic posturography and rotary chair test results were significantly improved. The rehabilitation patients were classified into the normal to mild subjective dizziness and moderate to severe subjective dizziness groups according to the dizziness handicap inventory score (cutoff of 40). Differences between the two groups were analyzed. RESULTS: After rehabilitation, 32.6% of the patients still complained of moderate to severe dizziness. Age, sex distribution, the presence of comorbidities, caloric weakness, pre- and postrehabilitation gain values in rotary chair test, postrehabilitation composite scores in posturography, and the duration of rehabilitation were not significantly different between the two groups. However, initial dizziness handicap inventory (DHI) score and composite score in dynamic posturography were worse and the proportion of patients with absent cervical vestibular-evoked myogenic potential in the moderate to severe group was much higher (93.3% vs. 35.5%, p < 0.001). After multiple regression analysis of those factors, initial DHI score and absent cervical vestibular-evoked myogenic potential response were identified as being associated with higher postrehabilitation DHI score. CONCLUSION: Saccular dysfunction in acute vestibular neuritis can contribute to persistent subjective dizziness, even after the objective parameters of vestibular function tests have been improved by vestibular rehabilitation.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

Porcine As a Training Module for Head and Neck Microvascular Reconstruction

Live models that resemble surgical conditions of humans are needed for training free-flap harvesting and anastomosis. Animal models for training purposes have been available for years in many surgical fields. We used the female (because they are easy to handle for the procedure) Yorkshire pigs for the head and neck reconstruction by harvesting the deep inferior epigastric artery perforator or the superior epigastric artery perforator flap. The anastomosis site (neck skin defect or tracheal wall defect) was prepared via the dissection of the common carotid artery and the internal jugular vein, in which 3.5× loupe magnification was used for anastomosis as we use on human cases in real life. This procedure demonstrates a new training method using a reliable learning model and provides a detailed anatomy in a live scenario. We focused on the ischemia time, harvesting, vessel anastomosis, and designing the flap to fit the defect site. This model improves tissue handling and with the use of proper instruments can be repeated many times so that the surgeon is fully confident before starting the surgery on humans.restrictio