[Vertigo/Dizziness as a Common Disease: Thinking in Terms of Risk].

Vertigo and dizziness are among the most common chief complaints in the neurology and emergency departments. Benign, self-limiting peripheral causes such as benign positional paroxysmal vertigo or vestibular neuropathy, Ménière's disease are the majority, but dangerous underlying conditions such as cerebrovascular or cardiovascular diseases are still overlooked. In this paper, the anatomy of the vestibular network from peripheral to central and the classification based on "triggers and timing" rather than the analysis of patient's word (rotational versus dizzy) are presented. Based on these, I classify various causes of vertigo and dizziness into three groups, i.e. highly dangerous, less dangerous but cautionary, and benign self-limiting ones, and explain them focusing on isolated vertigo or isolated vestibular syndrome.

[Application of the holism of body-qi-spirit in needle knife treatment for cervical vertigo].

This paper introduces Professor WANG Haidong's approach to treat cervical vertigo with needle knife based on the holism of body-qi-spirit. Professor WANG Haidong, considering the etiology and pathogenesis of cervical vertigo, starting from the holism of body-qi-spirit, based on the anatomical structure, employs the "seven-neck points" technique to improve local blood supply and address the physical issue; guided by the Jingjin theory, he utilizes the "knot releasing technique" to disperse knots and relax sinews, thereby regulating qi. In addition, he uses the "bone puncturing technique at governor vessel" to uplift yang-qi and nourish the brain, thereby nurturing the spirit.

The First 100 Children Treated in a Newly Established Pediatric Vertigo Center.

BACKGROUND: Correctly diagnosing dizziness in children is essential for appropriate management; nevertheless, healthcare professionals face challenges due to children's limited ability to describe their symptoms and their cooperation during physical examination. The objective of this study is to describe the first 100 patients seen at a newly established pediatric vertigo center. METHODS: This is a retrospective review of a consecutive series of 100 patients seen at our pediatric vertigo clinic in a tertiary referral center from August 2019 until June 2022. Comprehensive clinical data were collected. The diagnoses were established by 2 pediatric otolaryngologists based on validated diagnostic criteria. Trends in diagnosis, investigation, and treatment of these patients were analyzed. RESULTS: A total of 100 children were included in the study. Vestibular migraine was the most common diagnosis (20%) followed by benign paroxysmal vertigo of childhood (14%). Eleven patients had combined pathologies. Fifteen out of 70 children (21%) had abnormal audiograms, 30 out of 48 children (62.5%) had abnormal vestibular testing, and 6 out of 31 (19%) patients had abnormal imaging. Fifty-one children received medical treatment, 23 received vestibular physiotherapy, and 9 patients had particle repositioning maneuvers; moreover, 17 of these patients received multimodal treatment. CONCLUSIONS: Our analysis suggests that imaging and audiology testing have relatively low yield in the assessment of pediatric vertigo. On the other hand, vestibular testing detected a high proportion of abnormalities, such as saccadic pursuit, vertical nystagmus, central positional nystagmus, and abnormal directional preponderance, particularly associated with vestibular migraine. Given the complexity of diagnosing vertigo in children, it is critical to establish multidisciplinary specialized centers capable of providing accurate diagnosis and treatment for these children.

Feasibility of gamified visual desensitisation for visually-induced dizziness.

Visually-induced dizziness (visual vertigo) is a core symptom of Persistent Perceptual Postural Dizziness (PPPD) and occurs in other conditions and general populations. It is difficult to treat and lacks new treatments and research. We incorporated the existing rehabilitation approach of visual desensitisation into an online game environment to enhance control over visual motion and complexity. We report a mixed-methods feasibility trial assessing: Usage and adherence; rehabilitation potential; system usability and enjoyment; relationship with daily dizziness. Participants played online with (intervention, N = 37) or without (control, N = 39) the visual desensitisation component for up to 5-10 min, twice daily for 6 weeks. Dropout was 45%. In the intervention group, N = 17 played for the recommended time while N = 20 played less. Decreases in visual vertigo symptoms, anxiety and depression correlated with playtime for the intervention but not control. System usability was high. Daily symptoms predicted playtime. Qualitative responses broadly supported the gamified approach. The data suggest gamified visual desensitisation is accessible, acceptable and, if adherence challenges can be overcome, could become a useful addition to rehabilitation schedules for visually-induced dizziness and associated anxiety. Further trials are needed.

Postoperative Late Hearing Deterioration in Cholesteatoma with Labyrinthine Fistulas.

A labyrinthine fistula is a severe complication of middle ear cholesteatoma that can cause profound sensorineural hearing loss and vertigo. However, there is no consensus regarding the transition to postoperative hearing. Although hearing deteriorates gradually with a delay in some cases of labyrinthine fistula, insufficient consideration has been given to this point. We examined perioperative changes in cases of middle ear cholesteatoma with labyrinthine fistulas. We retrospectively reviewed the medical records of 578 patients with middle ear cholesteatoma who underwent tympanoplasty at our hospital between 2016 and 2021. Patients with labyrinthine fistulas were selected; their perioperative bone-conduction hearing was assessed. Fistula depth was determined following the classification reported by Dornhoffer et al. The hearing was compared preoperatively, early postoperatively (3-6 months), and 1 year postoperatively. Forty-eight patients (8.3%) had labyrinthine fistulas. Regarding depth, 21 cases were type I, 14 were type IIa, 3 were type IIb, and 10 were type III. Preoperative bone-conduction hearing was significantly poor in invasion type IIb or deeper cases. Cases with type IIb or deeper fistulas, multiple fistulas, or vertigo deteriorated postoperatively. Type III cases or those with multiple fistulas deteriorated further from the early postoperative period to 1 year postoperatively. Concerning frequency, 500 and 2000 Hz showed a delayed deterioration. This is a valuable report of delayed hearing loss after surgery in patients with a labyrinthine fistula. This change is associated with the labyrinthine fistula's depth and multiple fistulas-this is important during preoperative counseling of patients undergoing surgery.

Cervical and Ocular Vestibular Evoked Myogenic Potentials in Fibromyalgia Syndrome Patients.

BACKGROUND:  Fibromyalgia syndrome (FMS) is a chronic pain condition that may be associated with dysfunction in the central nervous system. OBJECTIVE: The aim of this study was to assess the vestibulo-spinal reflex (VSR) and vestibulo-ocular reflex (VOR) in FMS using the cervical vestibular evoked myogenic potential (cVEMP) and ocular vestibular evoked myogenic potential (oVEMP) tests, respectively, and to evaluate their relation to disease severity. METHODS:  This study included 30 female FMS patients and 30 well-matched healthy controls. They underwent full history taking and assessment of the severity of dizziness/vertigo using the Dizziness Handicap Inventory; assessment of the severity of FMS symptoms using the Revised Fibromyalgia Impact Questionnaire; bedside examination of the dizzy patient; videonystagmography, cVEMP, and oVEMP tests; basic audiologic evaluation; and uncomfortable loudness level (UCL) testing. RESULTS:  Dizziness was reported in 46.6% and vertigo in 11.1% of patients. Abnormalities in cVEMP (50%) and oVEMP (63.3%) were mostly unilateral, irrespective of FMS severity. Disease duration affected only the oVEMP amplitude. Fibromyalgia syndrome patients had a statistically significant lower UCL and narrower dynamic range compared to controls. CONCLUSION:  The VSR and VOR are commonly affected in FMS patients, and findings suggest central sensitization involving the brain stem. We recommend routine cVEMP and oVEMP testing to assess brainstem function in FMS patients.

[The VeSFADS structural classification of vestibular disorders].

The issuing of International Classification of Vestibular Disorders（ICVD） by Brny society（2015） greatly facilitates the progress of vestibular medicine. The syndromic classification of vestibular disorders by ICVD enable the physician to narrow the spectrum of differential diagnosis for the vestibular disorder in clinical practice. However, the division of vestibular pathway, especially the central vestibular system, has not be classified yet in the ICVD（2015）. Central vertigo, being a group of heterogeneous disorders, may present diverse clinical spectrums. The misdiagnosis of central vestibular as well as peripheral vestibular disorders have been reported in the clinic practice. Therefore, the author by review study proposes a structural classification of vestibular disorders combined the Vestibular System Functional Anatomy Division with Syndromes（VeSFADS）. The VeSFADS classification of vestibular disorders could help the physician in clinical practice to narrow the spectrum of vestibular disorders, in addition to the syndromic classification, by the clinical feature of vestibular disorders from different division of vestibular system. And the VeSFADS classification of vestibular disorders may facilitate to clarify the clinical features of vestibular disorders at different Division of vestibular pathway.

Cervical vertigo due to rotational fixation of atlantoaxial joint combined with benign paroxysmal positional vertigo: A case report and literature review.

INTRODUCTION: Vertigo is the most common clinical complaint, misdiagnosed patients are not rare, so it is very important to exclude and identify vertigo. For vertigo caused by multiple causes, including cervical vertigo with atlantoaxial rotation fixation combined with benign paroxysmal positional vertigo (BPPV), tuina can correct joint misalignment. The reduction technique will return the fallen otolith to the correct position. The use of massage and reduction can improve clinical symptoms and improve quality of life and may be a simple, safe, and effective treatment strategy for this disease. PATIENT CONCERNS: We report on a patient with both cervical vertigo due to atlantoaxial rotational fixation and BPPV, including his imaging examination, clinical manifestations, and treatment methods. DIAGNOSIS: Cervical vertigo (atlantoaxial rotatory fixation) and BPPV. INTERVENTION: Tuina combined with atlantoaxial directional inverted reduction technique and reduction manipulation. OUTCOMES: The patient's vertigo symptoms improved significantly, nystagmus disappeared, cervical occipital pain, nausea, head distension, and other symptoms disappeared, and cervical motion rotation reached 60°. CONCLUSION: This study proved the effectiveness of massage combined with a reduction in the treatment of cervical vertigo and BPPV, as well as the importance of vertigo diagnosis and differential diagnosis, and provided a new treatment idea for the future diagnosis and treatment of vertigo caused by a variety of causes.

[Metrology analysis and thoughts of literatures on tinnitus associated with sudden deafness based on CiteSpace].

Objective: To explore the incidence of sudden deafness accompanied with tinnitus, the selection of examination protocols and treatment, and to provide reference for the establishment of new guidelines for sudden deafness. Methods: CiteSpace software was used for analysis and data mining to analyze and summarize the computer-retrieved articles on diagnostic examination and treatment of sudden deafness accompanied with tinnitus collected from CNIC, Wanfang and Web of Science databases from 2011 to 2021. Results: A total of 207 randomized controlled studies were retrieved in this study, including 121 in Chinese and 86 in English. Finally, 74 Chinese literatures and 16 English literatures were included. Among the 74 valid Chinese literatures, 64 (86.5%) were accompanied with tinnitus, 58 (78.4%) with dizziness/vertigo, 25 (33.8%) with aural fullness, 10 (13.5%) with headache, 4 (5.4%) with insomnia, 4 (5.4%) with a mixture of dizziness and tinnitus, and 2 (2.7%) with vomiting. Among the 16 English literatures, 15 (93.8%) were accompanied with tinnitus, 12 (75.0%) with vertigo, 1 (6.3%) with aural fullness, and 1 (6.3%) with a mixture of various symptoms. Among the 64 Chinese articles mentioning tinnitus, only 9 mentioned tinnitus matching tests, and 1 mentioned that the treatment for tinnitus accompanying symptoms was sound therapy and psychological counseling. The incidence rates of tinnitus accompanying four different types of sudden deafness, from low to high, are as follows: low-to-mid frequency, 82.4%; mid-to-high frequency, 90.7%; complete deafness, 92.4%; and flat type, 92.8%. Conclusion: Tinnitus is the most common accompanying symptom of sudden deafness, and tinnitus matching test is an effective evaluation method. When establishing a scientific, comprehensive, and systematic diagnosis and treatment system or guidelines for sudden deafness, attention should be paid to the diagnosis and treatment of tinnitus symptoms and their adverse psychological reactions, in order to reduce the incidence of tinnitus patients in the later stage of recovery from sudden deafness.

[Vertigo and dizziness in child: a clinical analysis in 120 cases].

Objective: To investigate the disease composition, clinical features, diagnosis, and treatment characteristics of vertigo in children. Methods: A total of 120 children with vertigo diagnosed and treated in the Department of Otorhinolaryngology, Children's Hospital, Capital Institute of Pediatrics in Beijing from February 2018 to February 2022 were retrospectively analyzed to explore the clinical characteristics of common peripheral vertigo in children and to summarize the experience of diagnosis and treatment. Results: The etiological composition of 120 cases of vertigo in children are as follows: 63 (52.5%) cases of vestibular migraine of childhood (VMC), 19 (15.8%) of recurrent vertigo of childhood (RVC), 11 (9.2%) of probable vestibular migraine of childhood (PVMC), 10 (8.3%) of secretory otitis media (SOM), 6 (5.0%) of persistent postural-perceptual dizziness (PPPD), 4 (3.3%) of benign paroxysmal positional vertigo (BPPV), 2 (1.7%) of vestibular neuritis (VN), 2 (1.7%) of Meniere's disease (MD), 2 (1.7%) of inner ear malformation (IEM), and 1 (0.8%) of vestibular paroxysmal syndrome (VP).The major cause of vertigo in children of different ages was different. SOM was the most important cause in preschool children, followed by RVC and VMC; VMC was the most important cause in school-age children, followed by RVC; and MD and BPPV were exclusive found in adolescents. The incidence rate of PPPD was higher in adolescents than in preschool and school-age children. Children with vertigo had good prognosis in general. Conclusions: VMC, RVC and SOM are the most common causes in vertigo in children, and their proportion was different in different aged children. Transforming abstract feelings into specific information is the skill required for collecting medical history of children with vertigo. Considering the age and cooperation of children, appropriate hearing and vestibular examination techniques are recommended. We should pay more attention to the mental health of children with vertigo and their parents.

[Correlation between parameters of suppression head impulse paradigm and changesin DHI score in acute vestibular neuritis].

Objective:To explore the correlation between the parameters of suppression head impulse paradigm（SHIMP） and changes in dizziness handicap inventory（DHI） scores. Additionally, to evaluate the degree of vertigo and prognosis of patients with acute vestibular neuritis through SHIMP parameters. Methods:Thirty-three patients with acute vestibular neuritis were enrolled for DHI evaluation, vHIT and SHIMP. A secondary DHI score were evaluated after after two weeks, once patients no longer exhibited spontaneous nystagmus. The decrease in the second DHI score was used as the efficacy index（EI）. All patients were divided into significantly effective group, effective group and ineffective group based on EI. Differences of the VOR gain values of SHIMP and the anti-compensatory saccade were compared among the three groups. Results:There were 13 cases in the significant effective group, 11 cases in the effective group, and 9 cases in the ineffective group. ①The mean gain of the horizontal semicircular canal in the significant effective group, the effective group, and the ineffective group was（0.50±0.11）, （0.44±0.12）, and（0.34±0.08）, respectively. The difference between the significant effective group and the ineffective group was statistically significant（P<0.01）. The gain of horizontal semicircular canal was positively correlated with EI（r=0.538 5, P<0.01） 。②The occurrence rate of the anti-compensatory saccade in the significant effective group, the effective group, and the ineffective group was（51.23±19.59）, （33.64±17.68）, and（13.78±11.81）, respectively. Pairwise comparisons between each group showed statistical significance（P<0.05）. The occurrence rate of anti-compensatory saccade was positively correlated with EI（r=0.658 2, P<0.01）. Conclusion:The horizontal semicircular canal gain and the occurrence rate of the anti-compensatory saccade in SHIMP for patients with acute vestibular neuritis were closely correlated with decrease in DHI score.

Evaluating the impact of COVID-19 on vertigo and hearing impairment: A post-recovery analysis.

The COVID-19 pandemic, caused by the novel coronavirus SARS-CoV-2, has manifested with respiratory symptoms and a spectrum of extra-pulmonary complications. Emerging evidence suggests potential impacts on the auditory and vestibular systems, but the extent and nature of these effects in recovered individuals remain unclear. This study aimed to investigate the prevalence and severity of vertigo and hearing impairment in individuals who have recovered from COVID-19 and to identify potential risk factors associated with these sensory symptoms. A cohort of 250 recovered COVID-19 patients was assessed. Standardized questionnaires, including the Dizziness Handicap Inventory and the Vertigo Symptom Scale, were used to evaluate vertigo. Hearing assessment was conducted using pure-tone audiometry, speech audiometry, tympanometry, and oto-acoustic emissions testing. Logistic regression analysis was performed to assess the association between COVID-19 severity and the occurrence of sensory symptoms, controlling for confounding variables such as age and comorbidities. Of the participants, 10% reported vertigo, varying severity. Hearing assessments revealed that most participants had normal hearing, with an average speech discrimination score of 94.6. Logistic regression analysis indicated a significant association between severe COVID-19 and an increased likelihood of vertigo (OR 2.11, 95% CI 1.02-4.35, P = .043) and hearing impairment (OR 3.29, 95% CI 1.60-6.78, P = .002). This study suggests a significant association between COVID-19 severity and vertigo and hearing impairment prevalence. The findings underscore the importance of sensory symptom assessment in the post-recovery phase of COVID-19, highlighting the need for comprehensive healthcare approaches to manage long-term sequelae.

[Nape seven needles combined with pressing moxibustion for cervical vertigo: a randomized controlled trial].

OBJECTIVE: To observe the clinical effect of nape seven needles combined with pressing moxibustion for cervical vertigo (CV). METHODS: A total of 70 patients with CV were randomized into an observation group and a control group, 35 cases in each group. In the observation group, nape seven needles combined with pressing moxibustion was delivered, once a day, 6 times a week, for consecutive 2 weeks. In the control group, betahistine hydrochloride tablet and aceclofenac dispersible tablet were given orally, for 2 weeks and 3 days respectively. Before and after treatment, the evaluation scale for cervical vertigo (ESCV) score was observed, the plasma levels of neuropeptide Y (NPY), endothelin-1 (ET-1) and calcitonin gene related peptide (CGRP) were detected, the hemorheologic and hemodynamic indexes were measured, and the clinical efficacy was evaluated after treatment in the two groups. RESULTS: After treatment, the scores of dizziness, daily life and work ability, psychological and social adaptability, and headache, as well as the total scores of ESCV were increased compared with those before treatment (P<0.01, P<0.05) in the two groups, and the score and total score of neck and shoulder pain of ESCV was increased compared with that before treatment (P<0.01) in the observation group; each sub-item score and total score of ESCV in the observation group were higher than those in the control group (P<0.01, P<0.05). After treatment, the plasma levels of NPY and ET-1 were decreased compared with those before treatment (P<0.01), while the plasma levels of CGRP were increased compared with those before treatment (P<0.01, P<0.05) in the two groups; the plasma levels of NPY and ET-1 in the observation group were lower than those in the control group (P<0.01), the plasma level of CGRP in the observation group was higher than that in the control group (P<0.01). After treatment, the whole blood high shear viscosity, plasma viscosity and whole blood low shear viscosity were decreased compared with those before treatment (P<0.01, P<0.05), the mean velocity of basilar artery (BA), left vertebral artery (LVA) and right vertebral artery (RVA) were increased compared with those before treatment (P<0.05) in the two groups; the whole blood high shear viscosity, plasma viscosity and whole blood low shear viscosity in the observation group were lower than those in the control group (P<0.01), and the mean velocity of BA, LVA and RVA in the observation group were higher than those in the control group (P<0.05). The total effective rate in the observation group was 91.4% (32/35), which was superior to 71.4% (25/35) in the control group (P<0.05). CONCLUSION: Nape seven needles combined with pressing moxibustion can effectively alleviate the clinical symptoms, and improve the hemorheology and hemodynamics in CV patients.

Healthcare Costs due to Dizziness/Vertigo in Korea: Analyses Using the Public Data of Health Insurance Review & Assessment Service.

BACKGROUND: Dizziness/vertigo is one of the most common symptoms for which people seek healthcare. However, the healthcare expenditure attributable to dizziness/vertigo in South Korea remains poorly understood. We investigated the healthcare costs due to six major disorders causing dizziness/vertigo using claims data. METHODS: The healthcare costs were evaluated using all the claims data submitted to the Health Insurance Review and Assessment Service from January 1 to December 31, 2022. The six major vestibular disorders included for analysis were benign paroxysmal positional vertigo (BPPV), psychogenic/persistent postural perceptual dizziness (PPPD), vascular vertigo/dizziness (VVD), vestibular migraine (VM), Meniere's disease (MD), and vestibular neuritis (VN). RESULTS: During the 1-year study period, 4.1% of adults aged 20 or older visited hospitals due to dizziness/vertigo in South Korea. Compared to the general population, the patients with dizziness/vertigo were more often elderly, female, and residents of small towns. The total healthcare cost for the six major vestibular disorders was ₩547.8 billion (approximately $406.5 million). BPPV incurred the highest annual healthcare cost (₩183.5 billion, 33.5%), followed by VVD (₩158.8 billion, 29.0%), MD (₩82.2 billion, 15.0%), psychogenic/PPPD (₩60.3 billion, 11.0%), VN (₩32.9 billion, 6.0%), and VM (₩30.1 billion, 5.5%). The mean healthcare cost per hospital visit due to dizziness/vertigo was ₩96,524 (95% confidence interval, ₩96,194-₩96,855), 30% higher than the average (₩73,948) of the overall healthcare cost per hospital visit over the same period. CONCLUSION: Owing to higher healthcare costs for dizziness/vertigo and increased prevalence of dizziness/vertigo in the aged population, healthcare costs due to dizziness/vertigo will increase rapidly in South Korea. Thus, a guideline for cost-effective management of dizziness/vertigo should be established to reduce the healthcare costs due to these common symptoms.

Vestibular Migraine and Recurrent Vertigo in Children: A Diagnostic Focus From a Tertiary Hospital Study.

BACKGROUND: To improve diagnostic precision in pediatric vertigo, particularly in Vestibular Migraine of Childhood (VMC), probable VMC (pVMC), Recurrent Vertigo of Childhood (RVC), and unspecified categories, by delineating clinical characteristics and prevalence to refine diagnostics and treatments. METHODS: Retrospective analysis of 102 pediatric patients (five to 18 years; 46 females, 56 males) at the Dizziness Center of the Otolaryngology Department in a tertiary-level hospital from January 2019 to December 2023. Patients were classified into VMC, pVMC, RVC, and indeterminate groups. Evaluations included audiometry and vestibular tests (video head impulse test [vHIT] or caloric testing), conducted in the audiology unit and vestibular testing laboratory. Data were analyzed using IBM SPSS 20.0. RESULTS: Diagnoses were 8.8% VMC, 31.4% pVMC, 51.0% RVC, and 8.8% indeterminate. Nausea and vomiting were common in VMC and pVMC; cochlear symptoms like tinnitus and hearing loss predominated in VMC. Although vestibular testing showed no significant group differences, VMC had more vHIT abnormalities and RVC had more caloric test anomalies. CONCLUSIONS: This study highlights the need for comprehensive diagnostics in pediatric vestibular disorders, revealing unique and overlapping traits across VMC, pVMC, and RVC. Insights call for further research to refine diagnostic criteria and improve treatment methods.

Otology: Vertigo.

Vertigo, an unexpected feeling of self-motion, is no longer characterized simply by symptom quality but by using triggers and timing. Evaluating vertigo by triggers and timing not only distinguishes serious central causes from benign peripheral causes, but also narrows the differential diagnosis by further classifying vertigo as spontaneous episodic vestibular syndrome, triggered episodic vestibular syndrome, or acute vestibular syndrome. A targeted physical examination can then be used to further delineate the cause within each of these three vestibular categories. Neuroimaging and vestibular testing are not routinely recommended. In the management of vertigo, vestibular hypofunction can be treated with vestibular rehabilitation, which can be self-administered or directed by a physical therapist. Pharmacotherapy sometimes is indicated for vertigo based on triggers, timing, and the specific condition, but it is not always beneficial and is used more often for symptom reduction than as a cure. Transtympanic corticosteroid or gentamicin injections are recommended for patients who do not benefit from nonablative therapy. Surgical ablative therapy is reserved for patients who have not benefited from less definitive therapy and have nonusable hearing.

Inner ear decompression sickness after a routine dive and recompression chamber drill.

Inner ear decompression sickness (IEDCS) is an uncommon diving-related injury affecting the vestibulocochlear system, with symptoms typically including vertigo, tinnitus, and hearing loss, either in isolation or combination. Classically associated with deep, mixed-gas diving, more recent case series have shown that IEDCS is indeed possible after seemingly innocuous recreational dives, and there has been one previous report of IEDCS following routine hyperbaric chamber operations. The presence of right-to-left shunt (RLS), dehydration, and increases in intrathoracic pressure have been identified as risk factors for IEDCS, and previous studies have shown a predominance of vestibular rather than cochlear symptoms, with a preference for lateralization to the right side. Most importantly, rapid identification and initiation of recompression treatment are critical to preventing long-term or permanent inner ear deficits. This case of a U.S. Navy (USN) diver with previously unidentified RLS reemphasizes the potential for IEDCS following uncomplicated diving and recompression chamber operations - only the second reported instance of the latter.

Effects of sodium bicarbonate solution on hypergravity-induced Fos expression in neurons of the amygdala in rats: Implication of sodium bicarbonate therapy for vertigo.

OBJECTIVE: In Japan, intravenous injection of a 7 % solution of sodium bicarbonate (NaHCO3) had been originally developed to inhibit motion sickness and then have long been used to treat vertigo. Previously, we reported that Fos-positive neurons appear in the amygdala after hypergravity stimulation in rats. In the present study, we examined whether injection of 7 % NaHCO3 inhibits hypergravity-induced Fos expression in the neurons in the central nucleus of the amygdala in rats. METHODS: Rats were exposed to 2 G hypergravity in an animal centrifuge device for 3 h. A solution of 7 % NaHCO3 at a dose of 4 mM/kg was injected intraperitoneally before 2 G hypergraviy. Fos-positive neurons in the amygdala were stained immunohistochemically. RESULTS: The number of Fos-positive neurons in the central nucleus of the amygdala was significantly increased after 2 G hypergravity in rats that received no drugs or saline, compared to that in rats exposed only to the noise of the centrifuge and received 7 % NaHCO3 solution. The number of Fos-positive neurons in the central nucleus of the amygdala after 2 G hypergravity was significantly decreased in rats that received 7 % NaHCO3 solution, compared to that in rats that received no drugs or saline. CONCLUSION: Since Fos expression is a marker of activated neurons, the present findings suggest that hypergravity activates the amygdala and that administration of 7 % NaHCO3 suppresses hypergravity-induced activation of the amygdala. Hypergravity disturbs spatial orientation to produce motion sickness and the amygdala is involved in fear response. Recently, Ziemann et al. suggested that fear-evoking stimuli reduce the pH in the amygdala to activate it, leading to induction of fear behavior and that administering HCO3- attenuates fear behavior [Cell 2009; 139: 1012-1021]. Therefore, it is possible that hypergravity reduces the pH in the amygdala to activate it, thereby inducing the fear associated with motion sickness and that administration of 7 % NaHCO3 increases the brain pH thereby suppressing hypergravity-induced activation of the amygdala and inhibiting the fear associated with motion sickness. In patients with vertigo, 7 % NaHCO3 therapy may increase the brain pH thereby suppressing the activation of the amygdala and inhibiting the fear associated with vertigo to elicit a beneficial clinical effect.

The altered functional status in vestibular migraine: A meta-analysis.

PURPOSE: Vestibular migraine (VM) is a disorder with prominent vestibular symptoms that are causally correlated with migraine and is the most prevalent neurological cause of episodic vertigo. Nevertheless, the functional underpinnings of VM remain largely unclear. This study aimed to reveal concordant alteration patterns of functional connectivity (FC) in VM patients. METHODS: We searched literature measuring resting-state FC abnormalities of VM patients in PubMed, Embase, Cochrane, and Scopus databases before May 2023. Furthermore, we applied the anisotropic effect size-signed differential mapping (AES-SDM) to conduct a whole-brain voxel-wise meta-analysis to identify the convergence of FC alterations in VM patients. RESULTS: Nine studies containing 251 VM patients and 257 healthy controls (HCs) were included. Relative to HCs, VM patients showed reduced activity in the left superior temporal gyrus and left midcingulate/paracingulate gyri, and increased activity in the precuneus, right superior parietal gyrus, and right middle frontal gyrus. Jackknife's analysis and subgroup analysis further supported the generalization and robustness of the main results. Furthermore, meta-regression analyses indicated that the Dizziness Handicap Inventory (DHI) ratings were positively correlated with the activity in the precuneus, while higher Headache Impact Test-6 and DHI scores were associated with lower activity within the left midcingulate/paracingulate gyri. CONCLUSIONS: The study indicates that VM is associated with specific functional deficits of VM patients in crucial regions involved in the vestibular and pain networks and provides further information on the pathophysiological mechanisms of VM.

Latent class analysis of migraine associated vestibular-auditory symptoms.

OBJECTIVE: This study aimed to identify the potential subgroups of migraines based on the patterns of migraine associated symptoms, vestibular and auditory symptoms using latent class analysis and to explore their characteristics. METHOD: A total of 555 patients with migraine participated in the study. Symptoms such as nausea, vomiting, photophobia, phonophobia, osmophobia, visual symptoms, vestibular symptoms (dizziness, vertigo), and auditory symptoms (tinnitus, hearing loss, aural fullness) were assessed. Latent class analysis was performed to identify subgroups of migraines. Covariates such as gender, age of migraine onset, frequency of migraine attacks per month, and family history were also considered. RESULTS: The analysis revealed four latent classes: the Prominent Vestibular; Prominent Nausea; Presenting Symptoms but not prominent or dominant; and Sensory Hypersensitivity groups. Various covariates, such as gender, age of migraine onset, and frequency of migraine attacks, demonstrated significant differences among the four groups. The Sensory Hypersensitivity group showed the presence of multiple sensory symptoms, earlier age of migraine onset, and higher proportion of females. The Prominent Vestibular group had the highest probability of dizziness or vertigo but lacked the presence of auditory symptoms. The Prominent Nausea group exhibited prominent nausea. The Presenting Symptoms but not prominent or dominant group comprised individuals with the highest migraine attacks per month and proportion of chronic migraine. CONCLUSION: This study identifies four subgroups of migraines based on the patterns of symptoms. The findings suggest potential different but overlapped mechanisms behind the vestibular and auditory symptoms of migraine. Considering the different patterns of migraine-related symptoms may provide deeper insights for patients' prognosis and clinical decision-making.