Recurrence Rate and Risk Factors of Recurrence in Benign Paroxysmal Positional Vertigo: a Single-Center Long-Term Prospective Study With a Large Cohort.

OBJECTIVE: This study aimed to assess the long-term recurrence rate and correlations between recurrence and potential risk factors in patients with benign paroxysmal positional vertigo (BPPV). DESIGN: A total of 548 consecutive patients who demonstrated typical posterior or horizontal BPPV between January 2010 and December 2012 were included in this prospective study. All patients were contacted by phone every 6 months for 5 years and were asked to revisit the clinic when they experienced positional vertigo to be reexamined for recurrence. Recurrence of BPPV was defined as having positional vertigo and nystagmus confirmed following a symptom-free period of at least 7 days after complete resolution. We assessed the 5-year recurrence rate of BPPV, and the time point of recurrence in all patients as well as the risk factors of BPPV recurrence, including the clinical characteristics, therapeutic results of BPPV, and various comorbidities. RESULTS: Among the 548 patients, 121 (22.1 %) had at least one recurrence. Of these, 78 patients (54.5%) had only one recurrence within 5 years, while 43 (45.5%) patients experienced two or more recurrences. A recurrence occurred within 1 year in 82 patients (67.8%). The Cox proportional hazard ratio analysis found that head trauma (p = 0.015), Meniere's disease (p = 0.016), the number of canalith repositioning procedures performed (p = 0.037), and the number of previous vertigo attacks (p = 0.038) were significant risk factors of BPPV recurrence as opposed to hypertension or hyperlipidemia. CONCLUSIONS: The recurrence rate of BPPV was 22.1% at 5 years after the initial treatment. About 70% of recurred patients had a recurrence within 1 year. Head trauma, ipsilateral Meniere's disease, the number of canalith repositioning procedures performed, and the number of previous vertigo attacks were significant risk factors of BPPV recurrence.

A multicenter randomized double-blind study: comparison of the Epley, Semont, and sham maneuvers for the treatment of posterior canal benign paroxysmal positional vertigo.

We evaluated the short-term efficacy of Epley, Semont, and sham maneuvers for resolving posterior canal benign paroxysmal positional vertigo (BPPV) in a prospective multicenter randomized double-blind controlled study. Subjects were randomly divided into three groups: Epley (36 patients), Semont (32 patients), and sham (Epley maneuver for the unaffected side, 31 patients). Out of 14 institutes which participated in this study, 5 institutes had previous experience of the Epley but not the Semont maneuver and the other 9 had previous experience of both maneuvers. Each maneuver was repeated twice if there was still positional vertigo or nystagmus on day 0, and the presence of nystagmus and vertigo on positional testing were evaluated immediately, 1 day, and 1 week after treatment. After the first maneuver, the Epley group showed a significantly higher resolution rate of positional nystagmus than the Semont or sham groups (63.9, 37.5, and 38.7%, respectively). After the second maneuver, the resolution rate (83.3%) of the Epley group was significantly higher than that (51.6%) of the sham group. At 1 day and 1 week after treatment, the resolution rate of the Epley group was significantly higher than those of the other groups. Similar results were seen for the resolution of positional vertigo. The Epley maneuver showed persistent resolution rates of positional vertigo and nystagmus without a fatigue phenomenon. The Epley maneuver was significantly more effective per maneuver than Semont or sham maneuvers for the short-term treatment of posterior canal BPPV. The Semont maneuver showed a higher success rate than the sham maneuver, but it was not significantly different.

Vitamin D supplementation in preventing the recurrence of benign paroxysmal positional vertigo.

Objective: To evaluate the effect of vitamin D supplementation on the recurrence rate of benign paroxysmal positional vertigo (BPPV). Methods: A single-center, prospective, double-blind, placebo-controlled, parallel-group randomized controlled trial was conducted between November 2018 and May 2020. After successful treatment with canalith repositioning maneuvers, patients diagnosed with BPPV were randomized to either the vitamin D (n = 20) or placebo (n = 18) group. Only patients with serum vitamin D levels <20 ng mL-1 were included. The vitamin D group received 7000 IU of vitamin D weekly for a year, while the placebo group received a matching placebo drug. The final endpoint was the BPPV recurrence rate and correlation with serum vitamin D levels after 6 and 12 months in both groups. Results: Among 38 patients, 37 were followed up for 6 months and 30 for 12 months. Significantly higher serum vitamin D levels were observed in the vitamin D group compared to the placebo group at both the 6-month and 1-year follow-ups (p < .001 at each timepoint). The recurrence rate was lower in the vitamin D group than in the placebo group after 6 months (p = .008) and 1 year (p = .003). Conclusion: Vitamin D supplementation, in the absence of calcium, may be beneficial for patients prone to recurrent BPPV episodes, particularly when serum vitamin D levels are suboptimal (PRE20181024-001, Clinical Research Information Service, South Korea). Level of Evidence: 1b.

Nationwide Prevalence of Video Head Impulse Test Abnormality and its Risk Factors in South Korea.

OBJECTIVE: To identify the prevalence of and relevant information for video head impulse test (vHIT) abnormality in a large population. STUDY DESIGN: A cross-sectional design. SETTING: Korean National Health and Nutrition Examination Survey, 2021. METHODS: The sample was representative of the Korean population, with 2237 participants aged ≥40 years. A vHIT was performed to evaluate vestibular function. The vestibulo-ocular reflex (VOR) gain and the presence of reproducible catch-up saccades was assessed in a vHIT. Participants also completed questionnaires for demographics, socioeconomic status, and basic information regarding systemic diseases and dizziness and underwent hearing tests with automated pure-tone audiometry. RESULTS: The prevalence of vHIT abnormality was 22.5%, with unilateral (14.3%) being more common than bilateral (8.2%). The prevalence of vHIT abnormality increased significantly with age, with the highest rate observed in individuals aged >70 years (42.5%). Both hearing and VOR gain deteriorated with age, but the patterns of age-related progression were different. While hearing loss (HL) deteriorated gradually and progressively throughout adulthood, VOR gain deterioration was markedly evident after 70 years of age. CONCLUSION: Considering the high prevalence of vHIT abnormality, appropriate social and medical policies are needed to prevent associated injuries and improve patients' quality of life. The distinct age-related changes in HL and objective findings of vestibular dysfunction indicate the need for different approaches to address these social problems in aging countries.

Feasibility of an inertial measurement unit sensor-based guiding system for benign paroxysmal positional vertigo treatment: A pilot study.

Performing an accurate canalith repositioning procedure (CRP) is important for treating benign paroxysmal positional vertigo, because inadequate rotational head angles can result in ineffective otolith mobilization and consequent treatment failure. Specialists-guided Epley maneuver reportedly had mean errors of 13.7°-24.4° while they were significantly larger (40.0°-51.5°) when self-administered. Similar results were obtained for the Barbeque maneuver: mean errors were 9.2°-13.0° by the specialists while they were significantly larger (22.9°-28.6°) when self-administered. Our study aimed to validate the feasibility of an inertial measurement unit sensor-based CRP (IMU-CRP) by analyzing the differences in accuracy in the rotational angles, comparing them with education-based conventional CRP (EDU-CRP). A pilot validation was also performed by analyzing the treatment success rate of IMU-CRP in patients with BPPV. This single-institution prospective, comparative effectiveness study examined 19 participants without active vertigo or prior knowledge of benign paroxysmal positional vertigo and CRP. Participants conducted the Epley and Barbeque roll maneuvers without and with auditory guidance (EDU-CRP vs. IMU-CRP, respectively) twice, and head rotation accuracies were compared. Differences in target angles based on the American Academy of Otolaryngology-Head and Neck Surgery guidelines were considered errors. For BPPV participants, treatment success was assessed based on the presence or absence of nystagmus, vertigo, and dizziness. For all the Epley and Barbeque roll maneuvers steps, the absolute errors were smaller for IMU- than for EDU-CRPs, with significant differences in steps 2-4 and 3-6 of the Epley and Barbeque roll maneuvers, respectively. A learning effect was found in steps 4 and 5 of the Barbeque roll maneuver but not in the Epley maneuver. The treatment success rates after 1 h were 71.4% and 100% for the Epley and Barbeque roll maneuvers, respectively. Real-time feedback on head rotation angles induced more appropriate movements in the Epley and Barbeque roll maneuvers. A guiding device based on head monitoring providing real-time auditory feedback may increase the self-administered CRP success rates in treating benign paroxysmal positional vertigo.

Circulatory disturbance of the cochlear spiral modiolar artery in a type 2 diabetic mouse model.

Objective: This study aimed to identify significant differences in cochlea microvessel size between a diabetic mouse model (db/db) and normal mice using three-dimensional (3D) quantitative analysis. Methods: Six control heterozygote db/+ as well as 18 male B6/BKS(D)-Leprdb/J (db/db) mice aged 14 (n = 9) and 28 (n = 9) weeks were examined. After clearing the cochlea, we reconstructed the 3D volumes of the spiral modiolar artery (SMA) in the cochlea using light-sheet microscopy and analyzed vessel wall thickness, cross-sectional area, short and long diameter, and vessel height. Results: The average SMA-wall thickness in the db/db-mouse group (3.418 ± 0.328 µm) was greater than that in the control group (2.388 ± 0.411 µm). The average cross-sectional outer area, short diameter, and long diameter of the SMA in db/db mice were significantly larger than those in control mice (all p < 0.001). The cross-sectional areas increased with age (control: 221.782 ± 121.230 µm, 14 weeks; 294.378 ± 151.008 µm, and 28 weeks; 312.925 ± 147.943 µm). Conclusion: The db/db mice had thicker and larger proximal-SMA vessel walls and diameters than control mice, respectively, thus potentially inducing increased blood viscosity or vascular insufficiency and aggravating hearing loss in type 2 diabetes mellitus. Level of Evidence: IIb.

Unusual Foreign Body, a Spoon, in the Esophagus of a Middle-Aged Female: A Case Report and Review of the Literature.

In adults, a large metal foreign body in the esophagus is rarely seen and is usually caused accidentally. Here, we have described an unusual case of foreign body (spoon) in the esophagus of an adult patient. A 48-year-old woman initially presented to the emergency department with marked dysphagia, drooling, and radiating pain to the chest. She had swallowed a spoon while trying to vomit because of feeling sick. Radiological images revealed a spoon stuck in the esophagus. The edge of the spoon was grabbed with forceps and safely extracted under hypnic anesthesia. No esophageal perforation was detected on evaluation with esophagography using Gastrografin on the next day. This case highlights an unusual situation in an adult patient showing long nonfood-type foreign body in the esophagus. It is important that an appropriate workup and removal of foreign body is performed according to the location and type.

Saccular Pathology Is Most Commonly Found in Patients With General Vestibular Disorders.

OBJECTIVES: The first purpose of this study was to investigate the difference in the frequency of involvement of the superior vestibular nerve (SVN) and inferior vestibular nerve (IVN) territories in general vestibular disorders, and to identify which IVN territory was more commonly involved in patients with IVN lesions. The second purpose was to investigate the correlation of the degree of each saccular and posterior semicircular canal (PSCC) dysfunction, as represented by the parameters of cervical vestibular evoked myogenic potential (cVEMP) and video head impulse test (vHIT), in patients with pathology of the IVN territory. METHODS: In total, 346 patients with dizziness who underwent the caloric test, cVEMP, and vHIT were enrolled. Canal weakness in the caloric test, interaural amplitude difference (IAD) of cVEMP, and vestibulo-ocular reflex gain of the vestibulo-ocular reflex gain of the posterior semicircular canal (p-VOR) in vHIT were analyzed. RESULTS: Among the enrolled patients, 15.6% had total vestibular nerve dysfunction, 14.5% had solely SVN dysfunction, and 29.5% had solely IVN dysfunction. Isolated saccular pathology was most common in patients with IVN pathology, followed by those with total IVN dysfunction and PSCC dysfunction. IAD and p-VOR were statistically well correlated, and the correlation was strongest in patients with both pathologic IAD and pathologic p-VOR (n=23, r=0.944), followed by patients with normal IAD and pathologic p-VOR (n=27, r=0.762) and patients with pathologic IAD and normal p-VOR (n=106, r=0.339). CONCLUSION: Abnormal results were more common in vestibular tests investigating the IVN than in vestibular tests investigating the SVN in patients with general vestibular disorders. Isolated saccular pathology was more frequent than PSCC or combined pathology in patients with IVN dysfunction. Patients with abnormal p-VOR in vHIT had a higher probability of having both saccular and PSCC pathologies than patients with an abnormal IAD. This study describes the characteristics of vestibular-system subregions and provides guidance for clinically interpreting the combination of cVEMP and vHIT results.

Pou3f4 deficiency causes defects in otic fibrocytes and stria vascularis by different mechanisms.

DFN3, the most prevalent X-linked hearing loss, is caused by mutations in the POU3F4 gene. Previous studies in Pou3f4 knockout mice suggest that defective otic fibrocytes in the spiral ligament of the cochlear lateral wall may underlie the hearing loss in DFN3. To better understand the pathological mechanisms of the DFN3 hearing loss, we analyzed inner ears of Pou3f4-deficient mice during development. Our results indicate that compartmentalization of the spiral ligament mesenchyme setting up boundaries for specific otic fibrocytes occurs normally in Pou3f4-deficient cochlea. However, differentiation of the compartmentalized mesenchyme into specific otic fibrocytes was blocked in the absence of Pou3f4 function. In addition, we found that stria vascularis in the cochlear lateral wall was also affected in Pou3f4-deficient cochlea. Unlike the otic fibrocytes, differentiation of stria vascularis was completed in the absence of Pou3f4 function, yet expression of Kir4.1 channels in the strial intermediate cells, essential for the sound transduction, was lost afterwards. These results suggest that Pou3f4 deficiency causes defects in both otic fibrocytes and stria vascularis at different developmental stages and by different pathological mechanisms, which may account for the progressive nature of DFN3 hearing loss.

Clinical Implications of Horizontal Beating Nystagmus Induced by Dix-Hallpike Test in the Diagnosis of Horizontal Canal Benign Paroxysmal Positional Vertigo.

OBJECTIVES: The purpose of this study was to identify the diverse patterns of nystagmus during the Dix-Hallpike test (DHT) and analyze their clinical significance in horizontal canal benign paroxysmal positional vertigo (HC-BPPV). STUDY DESIGN: Retrospective medical records review. PATIENTS: Two hundred ninety-five patients diagnosed with HC-BPPV. METHODS: Various nystagmus patterns identified during the DHT in patients with HC-BPPV were analyzed. The correlation between the affected side of HC-BPPV and the direction of the horizontal beating nystagmus (HBN) during the DHT was also analyzed. RESULTS: The nystagmus pattern during the DHT in 128 patients with geotropic HC-BPPV demonstrated, direction-changing positional nystagmus on both sides in 48 (37.5%) patients, HBN toward one side in 25 (19.6%) patients, and no nystagmus in 55 (42.9%) patients. In 144 patients with apogeotropic HC-BPPV, 54 (37.5%) patients presented with direction-changing positional nystagmus on both sides, 27 (18.8%) patients presented with HBN toward one side, and 63 (43.7%) patients did not show nystagmus during the DHT. The direction of HBN provoked by the DHT was significantly correlated with the affected side in each subtype of HC-BPPV (geotropic type, p = 0.049; apogeotropic type, p = 0.040; respectively). CONCLUSION: More than half of the patients with HC-BPPV (56.6%) showed HBN during the DHT. When HBN was present during the DHT, it may provide a clue for determining the subtype and affected side in diagnosis of HC-BPPV before performing the supine roll test.

Therapeutic efficacy of super-high-dose steroid therapy in patients with profound sudden sensorineural hearing loss: a comparison with conventional steroid therapy.

BACKGROUND: In patients with sudden sensorineural hearing loss (SSNHL), steroid therapy is an optional treatment method, but there is controversy about its dose. OBJECTIVE: We aimed to compare the efficacy of super-high-dose steroid therapy with that of conventional steroid therapy in patients with profound SSNHL (pSSNHL). MATERIAL AND METHODS: Fifty-two patients diagnosed with pSSNHL between March 2010 and May 2017 were divided into the following groups based on their steroid regimen: a conventional steroid regimen (prednisolone at 1.0 mg/kg/day for 10 days) was applied in Group 1, and a super-high-dose steroid regimen (prednisolone at 1.5 mg/kg/day for 14 days) was applied in Group 2. The treatment outcomes were compared between the groups at 2 and 4 weeks after the initial treatment by use of Siegel's criteria. RESULTS: Of the 52 patients, 31 were classified into Group 1 and 21 into Group 2. When comparing the proportion of patients in complete or partial recovery by Siegel's criteria, the recovery rate was significantly higher in Group 2 than in Group 1 (19% vs 0%, p = .022 at 2 weeks; 35.7% vs 7.4%, p = 0.035 at 4 weeks). CONCLUSIONS AND SIGNIFICANCE: Patients with pSSNHL treated using the super-high-dose steroid regimen demonstrated better recovery rates to serviceable hearing than did those treated using the conventional steroid regimen without significant complications.

The effect of surgical timing on functional outcomes of traumatic facial nerve paralysis.

BACKGROUND: The optimal timing for surgical exploration of traumatic facial paralysis to best preserve facial function is currently controversial. This article reviews the final outcomes of facial function in patients with traumatic intratemporal facial nerve injury according to the timing of surgical exploration. METHODS: We performed a retrospective review of 58 patients with complete facial nerve paralysis caused by temporal bone fractures as a result of head trauma between 1998 and 2007. Patients were divided into three groups according to the type of trauma. The only difference between patients in each group was the timing of the surgical exploration. Characteristics assessed in the study included type of trauma, location of facial nerve injury, timing of surgical intervention, audiometric findings, surgical approach, and long-term follow-up of recovery of facial nerve function, as assessed by two facial nerve grading systems. RESULTS: The final functional gains in early-operated patients were 3.7 +/- 0.59 on the House-Brackmann (HB) scale and 75.6 +/- 10.88 on the Sunnybrook scale. The outcome in late-operated patients was 2.17 +/- 0.52 on the HB scale and 34.7 +/- 16.95 on the Sunnybrook scale, and that of nonoperated patients was 2.0 +/- 0.63 on the HB scale and 26.8 +/- 6.27 on the Sunnybrook scale. CONCLUSION: This study demonstrated that some patients with traumatic facial nerve paralysis who had nerve conduction studies consistent with a poor prognosis regained considerable facial function after early surgical intervention. However, late exploration after facial nerve paralysis did not result in positive outcomes, regardless of the type of temporal bone fracture or the site of injury, and no difference was observed compared with conservative treatment.

Optimal reassessment time for treatment response in posterior canal benign paroxysmal positional vertigo.

OBJECTIVES/HYPOTHESIS: The present study aimed to evaluate the optimal reassessment time for treatment response in posterior canal benign paroxysmal positional vertigo (PC-BPPV) following the initial Epley maneuver. STUDY DESIGN: Prospective, single-blinded, randomized study. METHODS: One hundred eight patients with PC-BPPV agreed to participate. These patients received a single modified Epley maneuver (recommended by the 2008 American Academy of Otolaryngology-Head and Neck Surgery guidelines) daily until positional nystagmus disappeared during the Dix-Hallpike maneuver 24 hours after the treatment. Repeated Dix-Hallpike testing to reassess the treatment response was performed at 1 hour (post-1 hour), every 24 hours (post-24 hours) until the positional nystagmus resolved, 1 week (post-1 week), and 1 month (post-1 month) following the therapeutic maneuver. The difference in the resolution rates at post-1 hour and post-24 hours reassessment was analyzed, and the recurrence rates at post-1 week and post-1 month were evaluated. RESULTS: The resolution rate was 67.6% at post-1 hour, which increased to 79.6% at post-24 hours reassessment. There was a statistically significant difference in the results of the Dix-Hallpike test between post-1 hour and post-24 hours follow-up. After complete resolution, nine out of 108 patients (8.3%) demonstrated recurrence within 1 month. CONCLUSIONS: Reassessment after 24 hours following the initial Epley maneuver is more advantageous than a 1-hour follow-up in patients with PC-BPPV. This information may be helpful for clinicians in deciding the appropriate follow-up period after treatment for PC-BPPV. LEVEL OF EVIDENCE: 1b Laryngoscope, 130:496-499, 2020.

Double-blind randomized controlled trial on efficacy of cupulolith repositioning maneuver for treatment of apogeotropic horizontal canal benign paroxysmal positional vertigo.

Backgrounds: Although various therapeutic maneuvers have been proposed, it is still unclear which maneuver is better to treat apogeotropic horizontal canal benign paroxysmal positional vertigo (HC-BPPV).Objectives: This study aimed to assess the therapeutic efficacy of the cupulolith repositioning maneuver (CuRM) in apogeotropic HC-BPPV in comparison with the therapeutic head-shaking maneuver and modified Lempert maneuver.Materials and Method: This is double-blind randomized prospective study. Forty-nine consecutive patients diagnosed with apogeotropic HC-BPPV were allocated randomly to CuRM (n = 18), therapeutic head-shaking (n = 16), or modified Lempert maneuver (n = 15). The presence of nystagmus and vertigo on positional testing were evaluated at 30 min, on 1 day, and 1 week after treatment.Results: There were no significant differences in any clinical characteristics between the three groups at randomization. After a single trial of therapeutic maneuvers on the initial visit day, the CuRM (38.9%) and therapeutic head shaking maneuver (12.5%) did not show differences compared to modified Lempert maneuver (33.3%). The therapeutic effects on the 2nd day and at 1 week after treatment also did not differ between the three groups.Conclusions: Although the CuRM is theoretically considered to be a better therapeutic method, the therapeutic efficacy of CuRM was not statistically different compared to the other two maneuvers.

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 < 18-month interval exhibited maximum sensitivity and specificity for predicting poor prognosis. According to this value, we categorized patients into the early bilateral involvement group (EBIG, < 18 months' interval) and the late bilateral involvement group (LBIG, ≥ 18 months' interval). Patients with synchronous BMD and patients in the EBIG group exhibited poorer prognosis compared with patients with metachronous BMD and those in LBIG (p = 0.011 and p ≤ 0.001). Demographics, hearing threshold, vestibular deficit, and comorbidities were not significantly different between the two groups (p > 0.05). None of the patients exhibited systemic autoimmune disease. CONCLUSION: BMD with early bilateral progression exhibited poorer prognosis compared with late bilateral progression.

Typical sensory organization test findings and clinical implication in acute vestibular neuritis.

OBJECTIVE: Sensory organization test (SOT) is used to evaluate postural instability. We wanted to characterize the SOT findings in patients with acute vestibular neuritis (VN). METHODS: Eighty-seven patients with VN were enrolled. The bithermal caloric and SOT were performed, and the results were compared with those from the dizziness handicap inventory (DHI). Abnormal SOT patterns were classified: severe, visual vestibular, vestibular, inconsistent, or normal patterns. The results were also analyzed by sensory analysis (somatosensory, visual, vestibular, and visual preference) and composite scores. RESULTS: Sixty-one patients (70%) showed abnormal findings for conditions 5 and/or 6 (vestibular pattern), and half (30 of 61, 49%) of them showed additional abnormal results in more than conditions 5 and 6. In pattern analysis, the vestibular pattern (abnormal in conditions 5 and 6) was the most common pattern (36%), and the visual vestibular pattern (abnormal in conditions 4, 5, and 6) was the second most common (24%). In sensory analysis, vestibular dysfunction was observed in 59 patients (68%), visual dysfunction in 37 (43%), visual preference in 17 (20%), and somatosensory dysfunction in 5 (6%). Composite scores of SOT showed a significant correlation with the DHI scores, though no correlation was observed between DHI and caloric results (p<0.05). CONCLUSION: VN can adversely influence on postural instability, with more severe patterns as well as classical vestibular patterns, indicating that abnormal vestibular inputs can influence postural stability in all SOT conditions and subjective symptom in patients with acute VN is more closely associated with the postural instability rather than canal dysfunction.

Progressive hearing loss in vitamin A-deficient mice which may be protected by the activation of cochlear melanocyte.

Vitamin A deficiency (VAD) produces various pathologic phenotypes in humans and animals. However, evidence regarding the effect of VAD on hearing function has been inconsistent. In this study, we evaluated the effect of VAD on hearing function in two mouse models of VAD. Hearing ability was evaluated on the basis of auditory brainstem response from 3 to 20 weeks after birth in C57BL/6 (pigmented) and imprinting control region (albino) mice. The two mice strains were divided into the VAD (purified vitamin A-free diet from 7 days after pregnancy) and control (normal diet) groups. Albino VAD mice exhibited hearing loss after 6 weeks and became deaf at 18 weeks. Histological findings revealed degenerative changes in outer hair cells and neuronal loss in the spiral ganglion in albino VAD mice. In contrast, pigmented VAD mice, except those with middle-ear infection, showed no significant hearing loss. Interestingly, pigmented VAD mice exhibited melanocyte activation in the stria vascularis and upregulation of tyrosinase. Recovery of hearing after noise exposure was poorer in pigmented VAD mice than in control mice. In conclusion, complete VAD might be related to age-related or noise-induced hearing loss in mice, protection against which might involve melanocyte activation.

Vibration-induced nystagmus in patients with vestibular schwannoma: Characteristics and clinical implications.

OBJECTIVE: To investigate the clinical significance of vibration-induced nystagmus (VIN) in unilateral vestibular asymmetry and vestibular schwannoma. METHODS: Thirteen patients with vestibular schwannoma underwent the VIN test, in which stimulation was applied to the mastoid processes and sternocleidomastoid (SCM) muscles on the ipsilateral and contralateral sides of lesions. Preoperative VIN was measured, and changes in VIN were followed up for 6months after tumor removal. Significance of VIN was determined by evaluation of its sensitivity, correlation with vestibular function tests and tumor volume, and postoperative changes. RESULTS: The overall pre and postoperative sensitivities of VIN were 92.3% and 100%, respectively, considering stimulation at all four sites. Maximum slow-phase velocity (MSPV) of VIN was linearly correlated with caloric weakness and tumor volume, especially when stimulation was applied to the SCM muscle. Postoperative MSPV of VIN exhibited stronger linear correlation with postoperative changes in canal paresis value and inverse correlation with tumor size upon stimulation of the ipsilateral SCM muscle than upon stimulation of other sites. During the 6-month follow-up period, persistence of VIN without changes in MSPV was observed even after vestibular compensation. CONCLUSIONS: Evoking VIN by stimulation of the mastoid processes and SCM muscles is effective for detecting vestibular asymmetry. It could also help determine the degree of vestibular asymmetry and volume of vestibular schwannoma if stimulation is applied to the SCM muscle. SIGNIFICANCE: The results of this study could provide clues for the basic application of VIN in patients with vestibular loss and vestibular schwannoma.

Prevalence of vestibular and balance disorders in children and adolescents according to age: A multi-center study.

OBJECTIVES: Children differ from adults in the expression of dizziness symptoms and the causes of dizziness. In several studies, benign paroxysmal vertigo of childhood (BPVC) and vestibular migraine (VM) were seen exclusively in children with vertigo, but the age threshold used to define 'children' varies, and there are few reported studies about adolescents with dizziness. In this study, we investigated the prevalence of vestibular and balance disorders according to age category in a multi-center study (otolaryngology departments of 11 hospitals) of children and adolescents. METHODS: Children and adolescents aged under 18 who visited the otolaryngology departments of 11 hospitals for dizziness were included. We classified the patients into three categories: preschool (up to and including 6-year-olds), school age (7- to 12-year-olds), and adolescents (13- to 18-year-olds). These patients were reviewed retrospectively based on their clinical charts. RESULTS: In the preschool age group, BPVC was most common, followed by VM. In the school-age group, BPVC and VMs were most common, followed by psychogenic vertigo and benign paroxysmal positional vertigo (BPPV). In adolescents, VM was the most common, and Ménière's disease, cardiogenic vertigo, and BPVC, which are seen primarily in adults, were also seen in some adolescents. CONCLUSION: In children and adolescents with dizziness, VM and BPVC were the most common diseases, and prevalence of disease by age showed differing distributions. These findings will help in diagnosing and managing children and adolescents with vertigo.

The effect of allergen provocation on the nasal cycle estimated by acoustic rhinometry.

CONCLUSION: The overall duration and reciprocity of the nasal cycle were not changed after allergen provocation. The duration of immediate response was 38 min, but the amplitude of the nasal cycle was increased significantly after allergen provocation. OBJECTIVE: Nasal airflow is asymmetrical and subjected to spontaneous reciprocal changes which are referred to as the nasal cycle. Limited information is available on how this is affected by allergens. The purpose of this study was to evaluate the effects of allergen provocation on the nasal cycle. MATERIALS AND METHODS: This study was performed on 25 patients with allergic rhinitis and 25 subjects in a control group with no symptoms of allergic rhinitis. Acoustic rhinometry was used to test patients before and after allergen provocation. The patients underwent acoustic rhinometry at 15-min intervals for evaluation of nasal cycle and 3-min intervals for immediate response. RESULTS: With the allergic patients, 21 of the 25 patients (84.0%) showed a nasal cycle and they still had a nasal cycle after the allergen provocation. In the study on the changes in the immediate responses, the average recovery time was 38 min and the reduction rate of the non-patent side was higher than that of the patent side. Also, the average period of the nasal cycle was 153 min before the allergen provocation and 140 min on average after the allergen provocation; there were no statistical differences. The amplitude of each nasal cycle increased after allergen provocation and the difference had statistical meaning.