Gravity perception disturbance in patients with unilateral Meniere disease.

Objective: To investigate gravity perception disturbance (GPD) in patients with Meniere disease (MD), we classified GPD type based on the results of the head-tilt perception gain (HTPG) and the head-upright subjective visual vertical (HU-SVV) evaluated by the head-tilt SVV (HT-SVV) test in patients with unilateral MD. Methods: We conducted the HT-SVV test on 115 patients with unilateral MD and 115 healthy controls. Among the 115 patients, the period from the first vertigo episode to the examination (PFVE) was known for 91 patients. Results: The HT-SVV test classified 60.9% and 39.1% of patients with unilateral MD as GPD and non-GPD, respectively. GPD was classified according to HTPG/HU-SVV combinations as follows: Type A GPD (21.7%, normal HTPG/abnormal HU-SVV), Type B GPD (23.5%, abnormal HTPG/normal HU-SVV), and Type C GPD (15.7%, abnormal HTPG/abnormal HU-SVV). As the PFVE became longer, patients with non-GPD and Type A GPD decreased; however, those with Types B and C GPD increased. Conclusion: This study provides novel information on unilateral MD from the perspective of gravity perception by classifying GPD based on the results of the HT-SVV test. This study's findings suggest that overcompensation for vestibular dysfunction in patients with unilateral MD exhibited by large HTPG abnormalities may be strongly associated with persistent postural-perceptual dizziness. Level of Evidence: 3b.

Results of subjective visual vertical tests in patients with vertigo/dizziness.

OBJECTIVE: We previously established the head-tilt subjective visual vertical (HT-SVV) test to evaluate head-tilt perception gain (HTPG) in addition to the original head-upright SVV (HU-SVV) test (Wada-Y et al.: Laryngoscope Investig Otolaryngol, 2020). In this study, we aimed to investigate the HU-SVV and HT-SVV abnormality rates among patients with vertigo/dizziness. METHODS: Between July 2014 and December 2020, 357 patients were hospitalized for examining the HU-SVV and HT-SVV at our vertigo/dizziness center. Among these patients, 120 had Meniere's disease (MD), 99 had unilateral vestibular disease (UVD), 76 had benign paroxysmal positional vertigo (BPPV), 14 had vestibular migraine (VM), 13 had orthostatic dysfunction (OD), 12 had bilateral vestibular disease (BVD), 12 had central dizziness (CD), 7 had vestibular schwannoma (VS), and 4 had psychogenic dizziness (PD). We determined the reference values of the absolute HU-SVV (<2.5°) and HTPG (0.80-1.25) for the sitting position and used these for calculating the HU-SVV and HT-SVV abnormality rates in each type of vertigo/dizziness. RESULTS: Among the 357 patients, 111 had abnormal HU-SVV results (31.1%), 132 had abnormal HT-SVV results (37.0%), and 185 had abnormal HU-SVV and/or HT-SVV results (51.8%). The modified HT-SVV test in combination with the original HU-SVV test could detect gravity perception disturbance in patients with vertigo/dizziness significantly better than the original test alone (chi-square: p=0.00019). The HU-SVV, HT-SVV, and HU-SVV and/or HT-SVV abnormality rates were significantly higher in patients with peripheral vestibular diseases, i.e., MD, UVD, BPPV, and BVD than in those with other types of vertigo/dizziness, i.e., VM, OD, CD, VS, and PD (chi-square: p=0.010, p=0.020, and p=0.0025, respectively). CONCLUSION: These findings suggest that the combined HT-SVV and HU-SVV test could be a powerful neuro-otologic examination for detecting pathologies in the vestibular otolithic pathway.

Left parietal involvement in motion sickness susceptibility revealed by multimodal magnetic resonance imaging.

Susceptibility to motion sickness varies greatly across individuals. However, the neural mechanisms underlying this susceptibility remain largely unclear. To address this gap, the current study aimed to identify the neural correlates of motion sickness susceptibility using multimodal MRI. First, we compared resting-state functional connectivity between healthy individuals who were highly susceptible to motion sickness (N = 36) and age/sex-matched controls who showed low susceptibility (N = 36). Seed-based analysis revealed between-group differences in functional connectivity of core vestibular regions in the left posterior Sylvian fissure. A data-driven approach using intrinsic connectivity contrast found greater network centrality of the left intraparietal sulcus in high- rather than in low-susceptible individuals. Moreover, exploratory structural connectivity analysis uncovered an association between motion sickness susceptibility and white matter integrity in the left inferior fronto-occipital fasciculus. Taken together, our data indicate left parietal involvement in motion sickness susceptibility.

Bilateral Asymmetry in Ocular Counter-Rolling Reflex Is Associated With Individual Motion Sickness Susceptibility.

Accumulating evidence suggests that individual variations in vestibular functions are associated with motion sickness (MS) susceptibility. We investigated whether vestibular functions in the reflex and cortical pathways could predict the susceptibility of individuals to MS. MS-susceptible and control adults were recruited according to the Motion Sickness Susceptibility Questionnaire (MSSQ) score. Otolith reflex and cortical functions were assessed using the ocular counter rolling test and the head-tilt subjective visual vertical (HT-SVV) test, respectively. The bilateral asymmetry of each function was compared between the MS-susceptible and the control groups. Although the two tests for otolith functions were conducted using the same stimulation (lateral head tilt), bilateral asymmetry of otolith reflex rather than cortical function was significantly associated with MS susceptibility. Our data suggests that bilateral asymmetry in the otolith reflex pathway is capable of predicting susceptibility to MS to some extent. Our data also suggest that the association between vestibular function and MS susceptibility can vary based on the vehicle types. Future vehicles, such as self-driving cars, will make us aware of other vestibular functions associated with MS susceptibility.

Vestibular Morphological Asymmetry Associated With Motion Sickness Susceptibility.

Sensory conflicts leading to motion sickness can occur not only between but also within sensory modalities. The vestibular organs are located in both left and right inner ears, and their misalignment can be a source of self-motion related sensory conflicts. In the current study, using inner ear magnetic resonance imaging, we examined whether morphological asymmetry of the bilateral vestibular organs was associated with motion sickness susceptibility. The results showed a larger position asymmetry of bilateral vestibular organs in individuals with high rather than low susceptibility. In addition, vestibular position asymmetry was associated with reciprocal interaction (negative resting state functional connectivity) between vestibular and visuocortical regions in lowly, but not highly, susceptible individuals. In conclusion, these findings suggest that vestibular morphological asymmetry can be a source of sensory conflicts in individuals with dysfunctional reciprocal visuo-vestibular interactions, a putative neural mechanism for resolving sensory conflicts.

Head Roll-Tilt Subjective Visual Vertical Test in the Diagnosis of Persistent Postural-Perceptual Dizziness.

OBJECTIVE: To examine the validity of head roll-tilt subjective visual vertical (HT-SVV) in diagnosing persistent postural-perceptual dizziness (PPPD). STUDY DESIGN: Retrospective review. SETTING: Tertiary referral center. PATIENTS: Sixty-one patients with PPPD, 10 with unilateral vestibular hypofunction (UVH), and 11 with psychogenic dizziness (PD), showing chronic vestibular symptoms for >3 months. INTERVENTIONS: Head-tilt perception gain (HTPG, i.e., mean perceptual gain [perceived/actual tilt angle]) during right or left head tilt of approximately 30° (HT-SVV) and conventional head-upright SVV (UP-SVV) were measured. Bithermal caloric testing, cervical and ocular vestibular-evoked myogenic potentials (cVEMP and oVEMP), and posturography were conducted. MAIN OUTCOME MEASURES: Multiple comparisons were performed for the HT-SVV and other vestibular tests among the disease groups. A receiver operating characteristic curve was created to predict PPPD using HTPG. RESULTS: HTPG was significantly greater in the PPPD group than in the UVH and PD groups. There were no significant differences in UP-SVV, cVEMP, oVEMP, and posturography (foam ratio and Romberg ratio on foam) among the disease groups, while the UVH group had the highest canal paresis compared to the other two groups. The area under the curve of the receiver operating characteristic curve for predicting PPPD was 0.764, and the HTPG value of 1.202 had a specificity of 95.2% for diagnosing PPPD. CONCLUSIONS: While conventional vestibular tests including UP-SVV, VEMPs, and posturography did not show abnormalities in PPPD, high HTPG in the HT-SVV test, an excessive perception of head tilt, can be a specific marker for discriminating PPPD from other chronic vestibular diseases.

Large abdominal purpura of neonatal retroperitoneal kaposiform hemangioendothelioma.

Large abdominal purpuras may be caused by retroperitoneal kaposiform hemangioendothelioma with consumptive coagulopathy. Clinicians should perform serial ultrasonography studies to detect the sings of tumor until the final diagnosis is confirmed.

Effects of Vestibular Rehabilitation on Physical Activity and Subjective Dizziness in Patients With Chronic Peripheral Vestibular Disorders: A Six-Month Randomized Trial.

Introduction: The present study aimed to determine whether supervised vestibular rehabilitation therapy (VRT) by physical therapists (PTs) affects subjective dizziness in patients with chronic vestibular disorders, and whether supervised VRT-induced changes in subjective dizziness are related to the changes in physical activity levels in daily life. Methods: Patients (n = 47) with chronic peripheral vestibular disorders were randomly divided into the VRT group (n = 25) and control group (n = 22). Patients in the VRT group received weekly supervised visits from PTs for a period of 6 months. Every other month, both groups were advised by neuro-otologists to increase the amount of activity in their daily life. All patients wore an accelerometer device, which recorded their physical activity for seven successive days before the end of the intervention. Patients also completed the dizziness and unsteadiness questionnaires before and after the intervention. Results: Subjective dizziness decreased significantly regardless of whether supervised VRT was administered; however, dizziness evoked by social activity and head and body movements improved more significantly in the VRT group than in the control group. In the VRT group, there was a significant negative correlation between the increase in sedentary behavior and improvement in subjective dizziness, and a significant positive correlation between the increase in light physical activity and improvement in subjective dizziness at the second month of intervention. The VRT group showed a significantly higher rate of increase in light physical activity than the control group, after 6 months of intervention. Conclusion: Supervised VRT could be highly effective in treating subjective dizziness in patients with chronic peripheral vestibular disorders. We believe frequent (weekly) and medium-term (6 months) PT-guided interventions may be highly effective in enhancing physical activity in daily life, and may subsequently improve subjective dizziness in these patients. Trial registration: This clinical study was registered with University hospital Medical Information Network (identification number: 000028832). https://www.umin.ac.jp/.

Changes in the Results of the Subjective Visual Vertical Test After Endolymphatic Sac Drainage for Intractable Meniere's Disease.

OBJECTIVE: To investigate otolithic function before and after endolymphatic sac drainage (ELSD) for Meniere's disease (MD) by using the subjective visual vertical test (SVV) in the upright and tilted positions. METHODS: Eighteen patients with definite unilateral MD diagnosed in accordance with the American Academy of Otolaryngology Head and Neck Surgery criteria in 1995 and Barany Society criteria in 2015 were included. SVV in the upright position and the head-tilt position was performed preoperatively and on postoperative days 1, 5, 8, 28, and 112. Changes in the results of SVV in the upright position (UP-SVV) and head-tilt perception gain (HTPG) after surgery were measured. RESULTS: The average UP-SVV values significantly changed from 0.05° by the affected side before surgery to 2.5° by the unaffected side on the fifth postoperative day, followed by recovery to the normal range by the eighth postoperative day. The HTPG values for the unaffected side showed the maximum increase on postoperative day 5 during the present study period, although the values in the affected side did not alter significantly. CONCLUSION: ELSD for MD is a surgical treatment that involves less risk of otolith function damage and abnormalities in gravitational cognition. SVV in the head-tilt position could be one of the neuro-otologic examinations used to easily understand the vestibular compensatory process.

Patients with vertigo/dizziness of unknown origin during follow-ups by general otolaryngologists at outpatient town clinic.

OBJECTIVES: The purpose of this study was to access the contribution of vertigo/dizziness-related patients' interview and examinations during short-term hospitalization in determining the accurate final diagnosis of vertigo/dizziness of unknown origin. METHODS: We reviewed 1905 successive vertigo/dizziness patients at the Vertigo/Dizziness Center of Nara Medical University, who were introduced from general otolaryngologists at outpatient town clinic from May 2014 to April 2020. However, 244 patients were diagnosed with vertigo/dizziness of unknown origin (244/1905; 12.8%). Of these patients, 240 were hospitalized and underwent various examinations, including caloric test (C-test), video head impulse test (vHIT), vestibular evoked cervical myogenic potentials (cVEMP), subjective visual vertical (SVV), inner ear magnetic resonance imaging (ieMRI), Schellong test (S-test), and self-rating questionnaires of depression score (SDS). RESULTS: According to the examination data, together with interviewed vertigo/dizziness characteristics and daily changeable nystagmus findings, the final diagnoses were as follows: benign paroxysmal positional vertigo (BPPV: 107/240; 44.6%), orthostatic dysregulation (OD: 56/240; 23.3%), vestibular peripheral disease (VPD: 25/240; 10.4%), vestibular migraine (VM: 14/240; 5.8%), Meniere's disease (MD: 12/240; 5.0%), gravity perception disturbance (GPD: 10/240; 4.2%), psychogenic vertigo (Psycho: 10/240; 4.2%), and unknown (Unknown: 6/240; 2.5%). Supporting factors of final diagnosis was seen in gender, evoked dizziness, and positional nystagmus as BPPV; in evoked dizziness, S-test, and hypertension as OD; in evoked dizziness, head shaking after nystagmus, C-test, and vHIT as VPD; in gender, headache, and S-test as VM; in ear fullness and ieMRI as MD; in gender, evoked dizziness, and SVV as GPD; and in SDS as Psycho. To sum up, the ratios of Unknown were significantly reduced by this short-term hospitalization (244/1905→6/240). CONCLUSIONS: The answer lists for vertigo/dizziness of unknown origin obtained in the present study may be helpful for future general otolaryngologists at outpatient town clinic to better attain an accurate final diagnosis.

Effect of head roll-tilt on the subjective visual vertical in healthy participants: Towards better clinical measurement of gravity perception.

OBJECTIVE: Gravity perception is an essential function for spatial orientation and postural stability; however, its assessment is not easy. We evaluated the head-tilt perception gain (HTPG, that is, mean perceptual gain [perceived/actual tilt angle] during left or right head roll-tilt conditions) and head-upright subjective visual vertical (SVV) using a simple method developed by us to investigate the characteristics of gravity perception in healthy participants. METHODS: We measured the SVV and head roll-tilt angle during head roll-tilt within ±30° of vertical in the sitting and standing positions while the participant maintained an upright trunk (sitting, 434 participants; standing, 263 participants). We evaluated the head-upright SVV, HTPG, and laterality of the HTPG. RESULTS: We determined the reference ranges of the absolute head-upright SVV (<2.5°), HTPG (0.80-1.25), and HTPG laterality (<10%) for the sitting position. The head-upright SVV and HTPG laterality were not influenced by sex or age. However, the HTPG was significantly greater in women than in men and in middle-aged (30-64 years) and elderly (65-88 years) participants than in young participants (18-29 years). The HTPG, but not the head-upright SVV or HTPG laterality, was significantly higher in the standing vs sitting position. CONCLUSION: The HTPG is a novel parameter of gravity perception involving functions of the peripheral otolith and neck somatosensory systems to the central nervous system. The HTPG in healthy participants is influenced by age and sex in the sitting position and immediately increases after standing to reinforce the righting reflex for unstable posture, which was not seen in the head-upright SVV, previously considered the only parameter. LEVEL OF EVIDENCE: 4.

What diagnosis should we make for long-lasting vertiginous sensation after acute peripheral vertigo?

BACKGROUND: Differential diagnosis of persistent vertigo/dizziness in patients with a past history of vestibular neuritis (VN) and sudden deafness with vertigo (SDV) could sometimes be difficult for physicians due to variable vertiginous symptoms from rotatory to floating sensation. OBJECTIVES: The main purpose of the present study was to examine the associations between the findings of otology/neurotology examinations in patients at the chronic stage after VN and SDV. MATERIAL AND METHODS: We encountered 1789 successive vertigo/dizziness patients at the Vertigo/Dizziness Center in Nara Medical University between 2014 and 2018. Eighty-five patients were diagnosed as showing VN and 60 showed SDV according to the diagnostic guideline . The VN and SDV patients included 75 and 45 patients with chronic-stage of persistent vertigo/dizziness, of which 55 and 40 were enrolled into the present study. RESULTS: Persistent vertigo/dizziness after VN was attributable to delayed vestibular compensation (dVC: 33/55; 60.0%), secondary benign paroxysmal positional vertigo (sBPPV: 20/55; 36.4%), and secondary endolymphatic hydrops (sEH: 2/55; 3.6%), while that after SDV was attributable to sBPPV (20/40; 50.0%), sEH (16/40; 40.0%), and dVC (4/40; 10.0%). CONCLUSION AND SIGNIFICANCE: The present results could allow to simplify differential diagnosis of persistent vertigo/dizziness after VN and SDV such diseases as dVC, sBPPV, or sEH.

Postural stability against full-field dynamic visual disturbance in archery players.

 Objectives : The effects of full-field dynamic visual disturbance on body sway were examined in archery players (n = 24), ball game players (n = 35), and untrained subjects (n = 34). Methods : Participants were asked to stand on a platform surrounded a box, the inside of which was randomly dotted. After the box suddenly began to swing and continued to swing back and forth at a frequency of 0.42 Hz for 60 seconds in a damped sinusoidal waveform, the body center sway was recorded using a stabilometer. Results : Standard deviation (SD) of body center sway in the anterior-posterior direction suddenly increased just after the box began to swing, and gradually decreased as the box swung in a damped sinusoidal waveform. After a sudden initial increase in SD of body center sway, it significantly decreased in archery players, compared with that of ball game players 20 seconds or untrained subjects 15 and 20 seconds after the onset of the box motion. Conclusion : Archery players showed higher stability against visual disturbance, compared with ball game players and untrained subjects, suggesting that they rely on proprioceptive inputs to maintain balance, and that their training re-weights sensorimotor dominance from vision to proprioception for posture regulation to increase shooting accuracy. J. Med. Invest. 67 : 67-69, February, 2020.

Combination of head-up sleep and vertical recognition training may cure intractable motion-evoked dizziness with unknown origin.

Background: It has been reported that head-up sleep (HUS) prevents free-floating otoliths from entering canals and that vertical recognition training (VRT) promotes vestibular compensation.Aims/objectives: We would like to assess HUS and VRT for intractable motion-evoked dizziness, including possible benign paroxysmal positional vertigo (BPPV).Materials and methods: 162 patients diagnosed with intractable motion-evoked dizziness of unknown origin were enrolled and randomly divided into the following four groups: HUS-/VRT-, HUS+/VRT-, HUS-/VRT+, and HUS+/VRT+. The at-home interventions comprised HUS with an upper head position of 45° when lying down and VRT with a right down-left down 30° head inclination while watching the vertical index.Results: At the post-treatment 6th month, visual analogue scale (VAS) scores for vertiginous sensation were significantly lower in the HUS+/VRT + group than in the HUS+/VRT - and HUS-/VRT + groups, which were in turn significantly lower than those in the HUS-/VRT - group. VAS scores in the HUS-/VRT + group of patients with abnormal subjective visual vertical (SVV) were significantly lower than those in the HUS+/VRT - group, while those in the HUS+/VRT - group of patients with normal SVV were significantly lower than those in the HUS-/VRT + group.Conclusions: HUS and/or VRT is a good initial treatment for patients with intractable undiagnosed motion-evoked dizziness, including possible BPPV.

Results in caloric test, video head impulse test and inner ear MRI in patients with Ménière's disease.

OBJECTIVE: Our aim was to elucidate relationships between results from the caloric test (c-test), video Head Impulse Test (vHIT) and inner ear gadolinium-enhanced MRI (ieMRI) in patients with endolymphatic hydrops (EH), especially patients with Ménière's disease (MD). METHODS: We managed 1789 successive patients at the Vertigo/Dizziness Center in Nara Medical University from May 2014 to December 2018. After providing informed consent for vertigo/dizziness examinations, 281 patients were hospitalized to check their inner ear function for proper diagnosis and treatment. Then 76 participants underwent the c-test, vHIT and ieMRI. Among these 76 cases, 20 were diagnosed with MD (20/76; 26.3%) and 56 were non-MD (56/76; 73.7%) according to the 2015 diagnostic guideline of the International Classification of Vestibular Disorders. The MD group included 15 unilateral and 5 bilateral cases. The non-MD group included 22 benign paroxysmal positional vertigo, 10 vestibular neuritis, 8 sudden deafness with vertigo, 6 orthostatic dysregulation, 4 vestibular neuropathy and 6 others. Results in these examinations in the side of an active lesioned inner ear were representative in each peripheral case. RESULTS: Twenty-nine of the 76 patients (38.1%) showed discrepant results between the c-test (outside of normal range) and vHIT (within normal range). Twenty-two of 76 patients (28.9%) had a positive EH sign on ieMRI. The c-test/vHIT discrepancy percentage in MD (14/20; 70.0%) was significantly higher than that in non-MD (15/56; 26.8%) (p=0.00179). The positive EH sign in ieMRI percentage in MD (15/20; 75.0%) was significantly higher than that in non-MD (7/56; 12.5%) (p=0.0015). There was a significant positive relationship between the c-test/vHIT discrepancy and the positive EH sign (p=0.00058) in all 76 cases combined. However, there was no significant relationship between c-test/vHIT discrepancy and positive EH sign (p=0.13) in the 20 MD cases. Considering the 15 unilateral and 5 bilateral MD cases, the c-test/vHIT discrepancy was observed in 14 of the 25 affected ears. Positive signs of vestibular EH herniation into the cupula in the lateral semicircular canal was seen in 14 of the 25 MD ears. There was significant relationship between the c-test/vHIT discrepancy and EH herniation (p=0.0012) in MD ears. CONCLUSION: The present results suggest that patients with MD could have inner ear EH significantly more often than those with non-MD. In cases with MD, a positive EH sign on ieMRI did not always indicate a c-test/vHIT discrepancy; both findings may occur due to herniation of vestibular EH adjacent to the lateral semicircular canal.

Head-Up Sleep May Cure Patients With Intractable Benign Paroxysmal Positional Vertigo: A six-Month Randomized Trial.

OBJECTIVES: The aim of the present study was to assess head-position management for intractable idiopathic benign paroxysmal positional vertigo (BPPV) when lying down. We hypothesized that head-up sleep (HUS) could prevent free-floating otoliths from entering the semicircular canals. STUDY DESIGN: A prospective two-arm multicenter randomized controlled trial. METHODS: BPPV was diagnosed in 611 patients (611/1,520; 40.2%) according to the 2015 diagnostic guidelines issued by the International Classification of Vestibular Disorders. Among them, 201 patients were intractable (201/611; 32.9%), 88 of whom were idiopathic and subsequently enrolled in the study. Patients randomly received intervention with HUS at greater than 45° (n = 44) or head-down sleep (HDS; n = 44) when lying down. Before treatment, they completed several examinations, including subjective visual vertical (SVV). The specific diagnoses for the 88 patients with BPPV included horizontal type cupula (n = 40), horizontal type canal (n = 13), posterior type (n = 26), and probable and/or atypical BPPV (n = 9). RESULTS: Patient backgrounds did not differ significantly between the HUS and HDS groups. Visual analog scale (VAS) scores of vertiginous sensation were significantly lower in the HUS group than in the HDS group at both the third month and sixth month post-treatment. Positional/positioning nystagmus observed just before treatment disappeared significantly more often in the HUS group than in the HDS group until the sixth post-treatment month. Further, especially in HUS group, VAS scores in SVV- group (n = 24) were significantly lower than those in the SVV+ group (n = 20) sixth month post-treatment. CONCLUSIONS: Controlling free-floating otoliths is not easy due to aging of the otolith organs. Repeatedly returning the endless free-floating debris from the canals to the utricle through physical means is not a good strategy. Therefore, HUS when lying down at home could be recommended as an initial treatment for patients with intractable idiopathic BPPV. LEVEL OF EVIDENCE: 1b.

Idiopathic benign paroxysmal positional vertigo with persistent vertigo/dizziness sensation is associated with latent canal paresis, endolymphatic hydrops, and osteoporosis.

OBJECTIVE: The aim of the present study was to examine the association of neuro-otological examination, blood test, and scoring questionnaire data with treatment-resistant intractability in idiopathic benign paroxysmal positional vertigo (BPPV) patients. METHODS: We experienced 1520 successive vertigo/dizziness patients at the Vertigo/Dizziness Center in Nara Medical University during May 2014 to April 2018. Six hundred and eleven patients were diagnosed as BPPV (611/1520; 40.2%) according to the diagnostic guideline of the International Classification of Vestibular Disorder in 2015. Among BPPV patients, there were 201 intractable patients (201/611; 32.9%), 66 of whom were idiopathic and enrolled to be hospitalized and receive neuro-otological examinations, including the caloric test (C-test), vestibular evoked cervical myogenic potentials (cVEMP), subjective visual vertical (SVV), glycerol test (G-test), electrocochleogram (ECoG), inner ear magnetic resonance imaging (ieMRI), blood tests including anti-diuretic hormone (ADH) and bone alkaline phosphatase (BAP), and self-rating questionnaires of depression score (SDS). Sixty-six patients were diagnosed as horizontal type cupula (hBPPVcu; n=30), horizontal type canal (hBPPVca; n=10), posterior type (n=20), and probable and/or atypical BPPV (n=6). Data are presented as ratios (+) of the number of idiopathic BPPV patients with examination and questionnaire data outside of the normal range. RESULTS: The ratio (+) data were as follows: C-test=21.2% (14/66), cVEMP=24.2% (16/66), SVV=48.5% (32/66), G-test=18.2% (12/66), ECoG=18.2% (12/66), ieMRI=12.1% (8/66), ADH=9.1% (6/66), BAP=13.6% (9/66), and SDS=37.9% (25/66). Multivariate regression analysis revealed that the periods of persistent vertigo/dizziness were significantly longer in BPPV patients with hBPPVcu, C-test (+), endolymphatic hydrops (+), and BAP (+) compared with those with negative findings. CONCLUSION: Although patients with idiopathic BPPV are usually treatable and curable within 1 month, the presence of hBPPVcu, canal paresis, endolymphatic hydrops, and elevated BAP may make the disease intractable, and thus require additional treatments.

Ménière's disease with unremitting floating sensation is associated with canal paresis, gravity-sensitive dysfunction, mental illness, and bilaterality.

OBJECTIVE: The aim of the present study was to evaluate the association of neuro-otological examination, blood tests, and scoring questionnaire data with treatment-resistant intractability of persistent dizziness in Ménière's disease. METHODS: We managed 1520 successive vertigo/dizziness patients at the Vertigo/Dizziness Center in Nara Medical University from May 2014 to April 2018. Five hundred and twenty-two patients were diagnosed with Ménière's disease (522/1520; 34.3%) according to the 2015 diagnostic guideline of the International Classification of Vestibular Disorders. Among the patients with Ménière's disease there were 102 with intractable rotatory vertigo attacks for more than 3-6 months (102/522; 19.5%), including 20 bilateral cases (20/102; 19.6%), and 88 with intractable unremitting floating sensation rather than rotatory vertigo attacks for more than 3-6 months (88/522; 16.9%), including 28 bilateral cases (28/88; 31.8%). Sixty out of 88 cases with intractable unremitting floating sensation were unilateral and were enrolled for hospitalization to undergo neuro-otological examinations including pure-tone audiometry (PTA), the caloric test (C-test), vestibular evoked cervical myogenic potentials (cVEMP), subjective visual vertical (SVV) test, glycerol test (G-test), electrocochleogram (ECoG), inner ear magnetic resonance imaging (ieMRI), blood tests including anti-diuretic hormone (ADH) and bone alkaline phosphatase (BAP), and self-rating questionnaires of depression score (SDS). Data are presented as positive (+) ratios of the number of patients with examination and questionnaire data outside of the normal range. RESULTS: The ratios (+) were as follows: C-test=33.3% (20/60), cVEMP=25.0% (15/60), SVV=50.0% (30/60), G-test=55.0% (33/60), ECoG=63.3% (38/60), ieMRI=86.7% (52/60), ADH=35.0% (21/60), BAP=11.7% (7/60), and SDS=40.0% (24/60). Multivariate regression analysis revealed that the periods of persistent dizziness were significantly longer in unilateral Ménière's patients with C-test(+), SVV(+), and SDS(+) compared with those with negative findings. Additionally, the periods in bilateral cases were significantly longer than those in unilateral ones. CONCLUSIONS: Although approximately 70% of patients with Ménière's disease are usually treatable through the appropriate conservative medical therapy, the presence of canal paresis, gravity-sensitive dysfunction, neurosis/depression, and bilaterality may make the persistent dizziness intractable and may thus require additional treatments.

Wrist-Worn Electrodermal Activity as a Novel Neurophysiological Biomarker of Autonomic Symptoms in Spatial Disorientation.

Background: Spatial disorientation is one of the most frequent causes of aircraft accidents, and is thus a major problem affecting air safety. Although a number of studies have examined spatial disorientation, the precise physiological changes occurring as a direct result of spatial disorientation and motion sickness remain unclear. The present study sought to investigate electrodermal activity (EDA) and subjective autonomic symptoms during spatial disorientation training, and to develop an indicator of physiological changes for pilot candidates. Methods: In the current study, we investigated changes in EDA measured using a wrist-worn device, and subjective autonomic nervous system symptoms during spatial disorientation training for pilot candidates. We then used the Graybiel diagnostic criteria to develop a novel physiological biomarker. Results: We found that maximum EDA change and peak amplitude were significantly increased in participants with a Graybiel score of ≥3 points compared with those who scored < 2 points. Furthermore, for symptoms of cold sweating and saliva secretion (from the seven Graybiel diagnostic criteria), the maximum EDA change in participants with scores ≥1 point was significantly higher than that of participants scoring 0 points. Conclusion: Our results indicate that EDA data measured with a wrist-worn device could provide a useful method for objective evaluation of the severity of spatial disorientation and motion sickness.