Otoneurologic Dysfunctions in Migraine Patients With or Without Vertigo

Association between central sensitization, pain sensitivity and balance control in patients with migraine

BACKGROUND

Balance alterations are prevalent among pain conditions, including migraine. The mechanisms explaining the association between pain and balance are unclear, as well as whether levels of pain sensitivity correlate with impaired balance. Our aim was therefore to investigate the association between balance, central sensitization symptoms and pain sensitivity in patients with migraine.

METHODS

This cross-sectional study included 50 patients and demographic, clinical information, central sensitization inventory (CSI) and pain catastrophizing (PCS) scores were obtained. Patients underwent a standardized protocol evaluating balance and pain thresholds for cold (CPT), heat (HPT), mechanical (MPT) and pressure (PPT) in trigeminal (V1) and extra-trigeminal (C6) dermatomes. Data were analysed using Person's correlation, linear regression models and contrasting the presence and absence of central sensitization symptoms through T-tests.

RESULTS

Mild-to-moderate correlations were observed between balance and MPT in V1 (r = -0.24, p = 0.046) and C6 (r = -0.41, p = 0.002), CPT in V1 (r = 0.31, p = 0.026), CSI scores (r = 0.27, p = 0.029) and migraine frequency (r = 0.25, p = 0.040). Balance was explained by CPT and MPT (R2 = 0.32, p = 0.001). The variance of CSI was explained by PCS scores and balance (R2 = 0.28, p = 0.001). Patients with symptoms of central sensitization presented an increased balance impairment (p = 0.044) and higher catastrophizing levels (p = 0.001) in contrast to patients without symptoms.

CONCLUSION

Balance impairment is associated with reduced pain thresholds and higher CSI scores. These results may help to elucidate the aetiology of balance alterations among chronic pain conditions.

SIGNIFICANCE

For the first time, it has been shown that balance alterations can reflect greater pain sensitivity and signs of central sensitization in patients with migraine. This opens up perspectives for future studies to understand the mechanisms and further factors associated with balance and pain sensitivity in migraine.

Episodic Vertigo: A Narrative Review Based on a Single-Center Clinical Experience

(1) Background: Usually, the majority of patients suffering from vertigo and dizziness can be identified in four major categories: acute spontaneous vertigo, episodic (recurrent) vertigo, recurrent positional vertigo, and chronic imbalance. Our purpose is to retrospectively evaluate the main causes of episodic vertigo and to find indications for a reliable clinical suspicion useful for a definitive diagnosis, comparing patients affected by different presenting symptomatology (acute vertigo, recurrent episodic vertigo, and imbalance). (2) Methods: we retrospectively evaluated the clinical records in a population of 249 consecutive patients observed for vertigo in our tertiary referral center in the period 1 January 2019-31 January 2020. On the basis of the reported clinical history, patients were divided into three groups: patients with their first ever attack of vertigo, patients with recurrent vertigo and dizziness, and patients with chronic imbalance. (3) Results: On the basis of the results of the instrumental examination, we arbitrarily divided (for each type of symptoms) the patients in a group with a normal vestibular instrumental examination and a group of patients in which the clinical-instrumental evaluation showed some pathological results; a highly significant difference (p: 0.157) was found between recurrent and acute vertigo and between recurrent vertigo and imbalance. (4) Conclusions: Patients with recurrent vertigo more frequently exhibit a negative otoneurological examination since they are often examined in the intercritical phase. A precise and in-depth research of the patient's clinical history is the key to suspect or make a diagnosis together with the search for some instrumental or clinical hallmark, especially in cases where the clinical picture does not fully meet the international diagnostic criteria.

Vestibular and Oculomotor Findings in Vestibular Migraine Patients

BACKGROUND

Vestibular migraine (VM) is the most frequent etiology of recurrent spontaneous episodic vertigo. Vestibular and oculomotor abnormalities have been described in VM; however, the diagnosis is currently based on symptoms. The objective of this study was to determine the most frequent abnormalities in videonystagmography (VNG), caloric testing (Cal) and video head impulse test (vHIT) in patients with VM.

METHODS

A retrospective cohort study was conducted, including all VM and probable VM patients seen from January 2021 to July 2022. Demographics, auditory symptoms and results via VNG, Cal and vHIT were evaluated. VNG results were compared with a control group.

RESULTS

Sixty patients, 81.7% with VM and 18.3% with probable vestibular migraine, were included. VNG revealed the following abnormalities: 21.7% spontaneous nystagmus; 33.3% positional nystagmus, mostly central; 26.7% optokinetic nystagmus; 56.7% smooth pursuit abnormalities and 70% saccade test abnormalities, mostly velocity and latency. An abnormal unilateral caloric response was seen in 22.9%, while vHIT revealed a low gain in at least one canal in 21.7%, and saccades were seen in at least one canal with normal gains in 18.3%. Concordant results between Cal and lateral vHIT were seen in 77.1% of cases.

CONCLUSIONS

Although VM is a clinical diagnosis, vestibular and oculomotor abnormalities are commonly seen. The most frequent oculomotor findings were an abnormal saccade test, abnormal smooth pursuit and central positional nystagmus.

Balance disorders and migraine

BACKGROUND

Migraine is associated with motion sensitivity symptoms such as kinetosis, vestibular symptoms and balance alterations. While focus is given to headache management, addressing these symptoms is often neglected, although they are related to additional migraine burden and increased disability.

PURPOSE

Our aim is to disseminate the current understanding of the motion sensitivity symptoms among patients with migraine, with focus on balance impairments. We discuss the susceptibility of migraine to motion sensitivity, its suggested mechanisms, the balance alterations during quiet standing, mobility tasks and reactions to external perturbations. The role of migraine subdiagnosis, implications for clinical practice and future perspectives are also acknowledged.

IMPLICATIONS

Balance disorders are one of the signs reflecting a broader and complex spectrum of motion sensitivity, which are present even between attacks. Migraineurs are especially inherent to these symptoms probably due to brain hyperexcitability and to shared pathophysiological mechanisms. Patients, especially with aura and chronic migraine, exhibit balance instability during quiet standing under different surface and visual input conditions. Migraineurs demonstrated reduced limits of stability and lower performance on walk, transposing obstacles and sit to stand tasks. Only patients with aura present impairment of motor control reactions following external perturbations. Balance alterations are associated with falls and are influenced by aura, migraine frequency and psychosocial aspects, but not by vestibular symptoms or vestibular migraine diagnosis. There is a high demand for high quality of evidence regarding the assessment and care of motion sensitivity symptoms in migraineurs, considering approaches to manage not just the pain, but its associated symptoms.

Benign Paroxysmal Positional Vertigo Is Associated with an Increased Risk for Migraine Diagnosis: A Nationwide Population-Based Cohort Study

Previous studies reported an increased risk of benign paroxysmal positional vertigo (BPPV) in patients with migraine. Hence, we aimed to assess the risk of migraine in patients with BPPV. This cohort study was conducted using the Taiwan National Health Insurance Research Database. The BPPV cohort consisted of patients aged <45 years with a diagnosis of BPPV between 2000 and 2009. An age- and sex-matched comparison group free from a history of BPPV or migraine was selected. All cases were followed up from 1 January 2000 to 31 December 2010 or until death or a diagnosis of migraine. The baseline demographic characteristics in both groups were compared using Student's t-test and the chi-square test. Cox proportional hazards regression analysis was used to estimate the hazard ratio for migraine in the BPPV cohort compared with the comparison group after adjustment for age, sex, and comorbidities. Notably, 117 of the 1386 participants with BPPV and 146 of the 5544 participants without BPPV developed migraine. After adjustment for age, sex, and comorbidities, BPPV showed an adjusted hazard ratio indicating a 2.96-fold increased risk of migraine (95% confidence interval: 2.30-3.80, p < 0.001). We found that BPPV is associated with an increased risk of a migraine diagnosis.

Migraine and balance impairment: Influence of subdiagnosis, otoneurological function, falls, and psychosocial factors

OBJECTIVE

To assess the balance sensory organization among patients with migraine, considering the influence of migraine subdiagnosis, otoneurological function, falls, and psychosocial factors.

BACKGROUND

Migraine has been associated with vestibular symptoms and balance dysfunction; however, neither comprehensive balance assessment nor associated factors for greater impairment have been addressed thus far.

METHODS

Patients from a tertiary headache clinic with a diagnosis of episodic migraine with aura (MWA), without aura (MWoA), and chronic migraine (CM) were included for this cross-sectional study (30 patients per group). Thirty headache-free controls (CG) were recruited. Participants underwent a comprehensive evaluation protocol, including the Sensory Organization Test (SOT) and otoneurological examination. Questionnaires about fear of falls, dizziness disability, and kinesiophobia were administered.

RESULTS

All migraine groups presented lower composite SOT scores than controls (CG: 82.4 [95% confidence interval (CI): 79.5-85.3], MWoA: 76.5 [95% CI: 73.6-79.3], MWA: 66.5 [95% CI: 63.6-69.3], CM: 69.1 [95% CI: 66.3-72.0]; p < 0.0001). Compared to controls and to MWoA, MWA and CM groups exhibited greater vestibular (CG: 75.9 [95% CI: 71.3-80.4], MWoA: 67.3 [95% CI: 62.7-71.8], MWA: 55.7 [95% CI: 51.2-60.3], CM: 58.4 [95% CI: 53.8-63.0]; p < 0.0001) and visual functional impairment (CG: 89.6 [95% CI: 84.2-94.9], MWoA: 83.2 [95% CI: 77.9-88.6], MWA: 68.6 [95% CI: 63.3-74.0], CM: 71.9 [95% CI: 66.5-77.2], p < 0.0001). Fall events during the assessment were documented more often among patients with migraine (CG: 0.0, interquartile range [IQR], 0.0, 0.0); MWoA: 1.0 [IQR: 1.0, 1.0], MWA: 2.0 [IQR: 1.8, 4.3], CM: 1.0 [IQR: 1.0, 2.0]; p = 0.001). The SOT scores correlated with fear of falls (r = -0.44), dizziness disability (r = -0.37), kinesiophobia (r = -0.38), and migraine frequency (r = -0.38). There was no significant influence of the vestibular migraine diagnosis in the study outcomes when used as a covariate in the analysis (composite score [F = 3.33, p = 0.070], visual score [F = 2.11, p = 0.149], vestibular score [F = 1.88, p = 0.172], somatosensory score [F = 0.00, p = 0.993]).

CONCLUSIONS

Aura and greater migraine frequency were related to falls and balance impairment with sensory input manipulation, although no otoneurological alterations were detected. The diagnosis of vestibular migraine does not influence the balance performance. The vestibular/visual systems should be considered in the clinical examination and treatment of patients with migraine.

Brain Processing of Visual Self-Motion Stimuli in Patients With Migraine: An fMRI Study

OBJECTIVE

To investigate the behavioral and neuronal responses of patients with migraine to a visual simulation of self-motion through a virtual roller coaster ride in comparison to controls.

METHODS

Twenty consecutive patients with migraine from a university-based hospital headache clinic and 20 controls were included. Participants underwent an experiment where a visually displayed self-motion paradigm was presented based on customized roller coaster videos during fMRI. Within each video, blocks of motion stimulation were interleaved with low-speed upward motion in a random order. In the scanning intervals and after the experiment, participants rated their perceived level of vestibular symptoms and motion sickness during the videos. We hypothesized that patients with migraine will perceive more motion sickness and that it correlates with different central processing and brain responses.

RESULTS

Compared to controls, patients with migraine reported more dizziness (65% vs 30%; p = 0.03) and motion sickness (Simulator Sickness Questionnaire score 47.3 [95% confidence interval (CI), 37.1, 57.5] vs 24.3 [95% CI, 18.2, 30.4]) as well as longer symptom duration (01:19 minutes [95% CI, 00:51, 01:48] vs 00:27 minutes [95% CI, 00:03, 00:51]) and intensity (visual analogue scale score 0-100, 22.0 [95% CI, 14.8, 29.2] vs 9.9 [95% CI, 4.9, 14.7]) during the virtual roller coaster ride. Neuronal activity in patients with migraine was more pronounced in clusters within the superior (contrast estimate 3.005 [90% CI, 1.817, 4.194]) and inferior occipital gyrus (contrast estimate 1.759 [90% CI, 1.062, 2.456]), pontine nuclei (contrast estimate 0.665 [90% CI, 0.383, 0.946]), and within the cerebellar lobules V/VI (contrast estimate 0.672 [90% CI, 0.380, 0.964]), while decreased activity was seen in the cerebellar lobule VIIb (contrast estimate 0.787 [90% CI, 0.444, 1.130]) and in the middle frontal gyrus (contrast estimate 0.962 [90% CI, 0.557, 1.367]). These activations correlated with migraine disability (r = -0.46, p = 0.04) and motion sickness scores (r = 0.32, p = 0.04). We found enhanced connectivity between the pontine nuclei, cerebellar areas V/VI, and interior and superior occipital gyrus with numerous cortical areas in patients with migraine but not in controls.

CONCLUSIONS

Migraine is related to abnormal modulation of visual motion stimuli within superior and inferior occipital gyrus, middle frontal gyrus, pontine nuclei, and cerebellar lobules V, VI, and VIIb. These abnormalities relate to migraine disability and motion sickness susceptibility.

Vestibular Migraine and Its Comorbidities

Vestibular migraine (VM) is one of the most common neurologic causes of vertigo. Symptoms and International Classification of Headache Disorders criteria are used to diagnose VM because no objective tests, imaging or audiologic, have been shown to reliably diagnose this condition. Central auditory, peripheral, and central vestibular pathway involvement has been associated with VM. Although the interaction between migraine and other vestibular disorders can be a challenging scenario for diagnosis and treatment, there are data to show that vestibular rehabilitation and a variety of pharmacologic agents improve reported symptoms and vertigo frequency.

Clinical, oculographic, and vestibular test characteristics of vestibular migraine

BACKGROUND

We characterise the history, vestibular tests, ictal and interictal nystagmus in vestibular migraine.

METHOD

We present our observations on 101 adult-patients presenting to an outpatient facility with recurrent spontaneous and/or positional vertigo whose final diagnosis was vestibular migraine (n = 27) or probable vestibular migraine (n = 74). Ictal and interictal video-oculography, caloric and video head impulse tests, vestibular-evoked myogenic potentials and audiometry were performed.

RESULTS

Common presenting symptoms were headache (81.2%), spinning vertigo (72.3%), Mal de Débarquement (58.4%), and motion sensitivity (30.7%). With fixation denied, ictal and interictal spontaneous nystagmus was observed in 71.3 and 14.9%, and purely positional nystagmus in 25.8 and 55.4%. Spontaneous ictal nystagmus was horizontal in 49.5%, and vertical in 21.8%. Ictal spontaneous and positional nystagmus velocities were 5.3 ± 9.0°/s (range 0.0-57.4), and 10.4 ± 5.8°/s (0.0-99.9). Interictal spontaneous and positional nystagmus velocities were <3°/s in 91.8 and 23.3%. Nystagmus velocities were significantly higher when ictal (p < 0.001/confidence interval: 2.908‒6.733, p < 0.001/confidence interval: 5.308‒10.085). Normal lateral video head impulse test gains were found in 97.8% (mean gain 0.95 ± 0.12) and symmetric caloric results in 84.2% (mean canal paresis 7.0 ± 23.3%). Air- and bone-conducted cervical-vestibular-evoked myogenic potential amplitudes were symmetric in 88.4 and 93.4% (mean corrected amplitude 1.6 ± 0.7, 1.6 ± 0.8) with mean asymmetry ratios of 13.0 and 9.0%. Air- and bone-conducted ocular-vestibular-evoked myogenic potentials were symmetric in 67.7 and 97.2% (mean amplitude 9.2 ± 6.4 and 20.3 ± 12.8 µV) with mean asymmetry ratios of 15.7 and 9.9%. Audiometry was age consistent and symmetric in 85.5%.

CONCLUSION

Vestibular migraine is characterised by low velocity ictal spontaneous nystagmus, which can be horizontal, vertical, or torsional, and normal audiovestibular test results.

Episodic Spontaneous Dizziness

PURPOSE OF REVIEW

Conditions causing recurrent spontaneous episodes of dizziness or vertigo span several medical specialties, making it challenging for clinicians to gain confidence in evaluating and managing the spectrum of episodic vestibular disorders. Patients are often asymptomatic and have normal examinations at the time of evaluation. Thus, diagnosis depends heavily on eliciting key features from the history. Overreliance on symptom quality descriptions commonly leads to misdiagnosis. The goal of this article is to provide the reader with a straightforward approach to the diagnosis and management of conditions that cause episodic spontaneous dizziness.

RECENT FINDINGS

Consensus diagnostic criteria have been established for vestibular migraine, Ménière disease, vestibular paroxysmia, and hemodynamic orthostatic dizziness/vertigo. Vertigo has been recognized as a common symptom in vertebrobasilar ischemia, cardiogenic dizziness, and orthostatic hypotension. Treatment recommendations for vestibular migraine still lack high-quality evidence, but controlled trials are occurring.

SUMMARY

The evaluation should start with a detailed description of the episodes from the patient and any observers. Rather than focusing first on whether the symptom quality is most consistent with vertigo, dizziness, lightheadedness, or unsteadiness, the clinician should clarify the timing (episode frequency and duration), possible triggers or circumstances (eg, position changes, upright posture), and accompanying symptoms. History should identify any auditory symptoms, migraine features, posterior circulation ischemic symptoms, vascular risk factors, clues for anxiety, and potentially relevant medications. Carefully selected testing can help secure the diagnosis, but excessive and indiscriminate testing can lead to more confusion. Treatments for these conditions are vastly different, so an accurate diagnosis is critical.

The integration of multisensory motion stimuli is impaired in vestibular migraine patients

BACKGROUND

Vestibular migraine (VM) is a relatively recently acknowledged vestibular syndrome with a very relevant prevalence of about 10% among patients complaining of vertigo. The diagnostic criteria for VM have been recently published by the Bárány Society, and they are now included in the latest version of the International Classification of Headache Disorders, yet there is no instrumental test that supports the diagnosis of VM.

OBJECTIVE

In the hypothesis that the integration of different vestibular stimuli is functionally impaired in VM, we tested whether the combination of abrupt vestibular stimuli and full-field, moving visual stimuli would challenge vestibular migraine patients more than controls and other non-vestibular migraineurs.

METHODS

In three clinical centers, we compared the performance in the functional head impulse test (fHIT) without and with an optokinetic stimulus rotating in the frontal plane in a group of 44 controls (Ctrl), a group of 42 patients with migraine (not vestibular migraine, MnoV), a group of 39 patients with vestibular migraine (VM) and a group of 15 patients with vestibular neuritis (VN).

RESULTS

The optokinetic stimulation reduced the percentage of correct answers (%CA) in all groups, and in about 33% of the patients with migraine, in as many as 87% of VM patients and 60% of VN patients, this reduction was larger than expected from controls' data.

CONCLUSIONS

The comparison of the fHIT results without and with optokinetic stimulation unveils a functional vestibular impairment in VM that is not as large as the one detectable in VN, and that, in contrast with all the other patient groups, mainly impairs the capability to integrate different vestibular stimuli.

Video head impulse test in vestibular migraine

Introduction

Vestibular migraine as an entity was described in 1999 and its pathophysiology is still not established. Simultaneously with research to better understand vestibular migraine, there has been an improvement in vestibular function assessment. The video-head impulse test is one of the latest tools to evaluate vestibular function, measuring its vestibular-ocular reflex gain.

Objective

To evaluate vestibular function of vestibular migraine patients using video-head impulse test.

Methods

Cross-sectional case-control study homogeneous by age and gender with vestibular migraine patients according to the 2012–2013 Barany Society/International Headache Society diagnostic criteria submitted to video-head impulse test during intercrisis period.

Results

31 vestibular migraine patients were evaluated with a predominantly female group (90.3%) and mean age of 41 years old. Vestibular function was normal in both patient and control groups. Gain values for horizontal canals were similar between the two groups, but gain values for vertical canals were higher in the group with vestibular migraine (p < 0.05). Patients with vestibular migraine felt more dizziness while performing the video-head impulse test than control subjects (p < 0.001).

Conclusions

Patients with vestibular migraine present normal vestibular function during intercrisis period when evaluated by video-head impulse test. Vertical canals, however, have higher gains in patients with vestibular migraine than in control subjects. Vestibular migraine patients feel dizziness more often while conducting video-head impulse test.

Physical therapy and migraine: musculoskeletal and balance dysfunctions and their relevance for clinical practice

BACKGROUND

Migraine is a primary headache with high levels of associated disability that can be related to a variety of symptoms and comorbidities. The role of physical therapy in the management of migraine is largely unknown. Therefore, the aim of this review is to highlight and critically discuss the current literature and evidence for physical therapy interventions in individuals with migraines.

METHODS

A narrative review of the literature was performed.

RESULTS

Physical therapists assessing and treating patients with migraine should focus on two primary aspects: (1) musculoskeletal dysfunctions, and (2) vestibular symptoms/postural control impairment. Signs and symptoms of musculoskeletal and/or vestibular dysfunctions are prevalent among individuals with migraines and different disability levels can be observed depending on the presence of aura or increment of the migraine attacks.

CONCLUSION

A proper physical examination and interview of the patients will lead to a tailored treatment plan. The primary aim regarding musculoskeletal dysfunctions is to reduce pain and sensitization, and physical therapy interventions may include a combination of manual therapy, exercise therapy, and education. The aim regarding postural control impairment is to optimize function and reduce vestibular symptoms, and interventions should include balance exercises and vestibular rehabilitation. However, consistent evidence of benefits is still lacking due to the lack of and therefore need for tailored and pragmatic clinical trials with high methodological quality.

A case-control study of visually evoked postural responses in childhood with primary headaches

BACKGROUND

Disorientation, nausea, confusion, dizziness, and displacement are frequently complained by headache-suffering children. Anyhow, the cause of these symptoms is still unclear, and a dysfunction of vestibular pathways or their alteration due to central pain pathways hyper-activation, has been proposed. The aim of this study is to use posturography to explore the balance function of headache-suffering children during pain-free periods.

METHODS

Posturography was performed on 19 migraineurs, 11 tension-type headache sufferers, and 20 healthy controls. Posturographic measures were performed during headache-free periods under different conditions: with eyes opened, eyes closed, and during right and left optokinetic stimulation. The last 2 conditions were used to mimic unreliable visual signals that can confound vestibular system.

RESULTS

During eyes-closed conditions, headache-suffering children displayed higher displacements than healthy controls, since statokinesiogram surface was higher in tension-type headache sufferers and migraineurs compared with controls (P value = 0.0095). Romberg's index, indicating the overall stability of the subject, was lower in healthy controls than in headache sufferers (P = 0.0139), thus suggesting a vestibular impairment in the seconds. Moreover, both during right and left optokinetic stimulation, the statokinesiogram length was higher in headache-suffering children (P < 0.0001). Thereafter, statokinesiogram surface was higher in migraineurs during right optokinetic stimulation (P = 0.0388) than in tension-type headache sufferers when stimulation was directed on the opposite side (P = 0.0249).

CONCLUSIONS

These results suggest a central alteration of vestibular pathways in headache-suffering children, that makes balance function more dependent from visual inputs than healthy subjects, even in inter-ictal phases.

Vestibular Migraine

The term vestibular migraine designates recurrent vertigo that is caused by migraine. Vestibular migraine presents with episodes of spontaneous or positional vertigo lasting seconds to days that are accompanied by migraine symptoms. Because headache is often absent during acute attacks, other migraine features have to be identified by thorough history taking. In contrast, vestibular testing serves mainly for the exclusion of other diagnoses. Treatment still lacks solid evidence. It is targeted at the underlying migraine and comprises explanation and reassurance, lifestyle modifications, and drugs.

Vestibular migraine: An update on current understanding and future directions

BACKGROUND

Vestibular migraine is among the most common causes of recurrent vertigo in the general population. Despite its prevalence and high impact on healthcare cost and utilization, it has remained an under-recognized condition with largely unknown pathophysiology. In the present article, we aim to provide an overview of the current understanding of vestibular migraine.

METHODS

We undertook a narrative literature review on the epidemiology, presentations, clinical and laboratory findings, pathophysiology, and treatments of vestibular migraine.

RESULTS

Currently, the diagnosis of vestibular migraine relies solely on clinical symptoms since clinical tests of vestibular function are typically normal, or difficult to interpret based on inconsistent results reported in earlier studies. The challenges related to diagnosis of vestibular migraine lie in its relatively broad spectrum of manifestations, the absence of typical migraine headaches with vestibular symptoms, and its very recent definition as a distinct entity. Here, we highlight these challenges, discuss common vestibular symptoms and clinical presentations in vestibular migraine, and review the current aspects of its clinical diagnosis and evaluation. The concepts related to the pathophysiology and treatment of vestibular migraine are also discussed.

CONCLUSION

Vestibular migraine is still underdiagnosed clinically. Future studies are needed to address the pathophysiological mechanisms and investigate effective treatment regimens.

Definition of Balance and Cognition Related to Disability Levels in Vestibular Migraine Patients

Objective

To compare the balance and cognition of vestibular migraine (VM) patients with migraineurs without vertigo history and healthy subjects, and to examine the effects of disability level on these functions.

Material-method

The study consisted of 32 VM patients, 32 migraineurs and 31 healthy subjects with similar sex and age. Balance functions were assessed with Balance Evaluation Systems Test (BEST), dizziness and headache severity with Visual Analogue Scale (VAS), disability related to dizziness with Dizziness Handicap Inventory (DHI), cognition with Stroop test.

Results

There was no statistical significant difference among the three groups in terms of age, gender, height, weight, marital status and education levels (p>0.05). Headache severity was higher in migraineurs than vestibular migraineurs and healthy subjects, also dizziness severity was higher in vestibular migraineurs than migraineurs and healthy subjects (p<0.0167). The outcomes of BEST 4, 5, 6 and BEST-total were significantly impaired in VM patients than migraineurs and healthy subjects, and worse in migraineurs rather than healthy subjects (p<0.0167). Stroop effect of cognitive examination was worse in VM and migraine patients rather than healthy subjects (p<0.0167). There was no significantly difference between VM and migraineurs (p>0.0167). There was a negative correlation between Stroop effect and BEST-total in VM patients significantly (r=-0.509, p=0.003), and no significant correlation in migraineurs (p>0.05). Disability levels of VM patients were low in 38.7%, mild in 51.6% and severe in 9.7% related to DHI. There was no significant difference between balance and cognition function in terms of disability levels (p>0.05).

Conclusion

The balance and cognition in VM patients and migraineurs were impaired rather than healthy subjects. The patient groups differed from each other in terms of vertiginous complaints rather than cognition. Solving the functional limitations with further longitudinal examinations can facilitate the treatment. The appropriate physiotherapy programs and patient education methods can be planned for these various issues.

Contribution of intravestibular sensory conflict to motion sickness and dizziness in migraine disorders

Migraine is associated with enhanced motion sickness susceptibility and can cause episodic vertigo [vestibular migraine (VM)], but the mechanisms relating migraine to these vestibular symptoms remain uncertain. We tested the hypothesis that the central integration of rotational cues (from the semicircular canals) and gravitational cues (from the otolith organs) is abnormal in migraine patients. A postrotational tilt paradigm generated a conflict between canal cues (which indicate the head is rotating) and otolith cues (which indicate the head is tilted and stationary), and eye movements were measured to quantify two behaviors that are thought to minimize this conflict: suppression and reorientation of the central angular velocity signal, evidenced by attenuation ("dumping") of the vestibuloocular reflex and shifting of the rotational axis of the vestibuloocular reflex toward the earth vertical. We found that normal and migraine subjects, but not VM patients, displayed an inverse correlation between the extent of dumping and the size of the axis shift such that the net "conflict resolution" mediated through these two mechanisms approached an optimal value and that the residual sensory conflict in VM patients (but not migraine or normal subjects) correlated with motion sickness susceptibility. Our findings suggest that the brain normally controls the dynamic and spatial characteristics of central vestibular signals to minimize intravestibular sensory conflict and that this process is disrupted in VM, which may be responsible for the enhance motion intolerance and episodic vertigo that characterize this disorder.

Abnormal Tilt Perception During Centrifugation in Patients with Vestibular Migraine

Vestibular migraine (VM), defined as vestibular symptoms caused by migraine mechanisms, is very common but poorly understood. Because dizziness is often provoked in VM patients when the semicircular canals and otolith organs are stimulated concurrently (e.g., tilting the head relative to gravity), we measured tilt perception and eye movements in patients with VM and in migraine and normal control subjects during fixed-radius centrifugation, a paradigm that simultaneously modulates afferent signals from the semicircular canals and otoliths organs. Twenty-four patients (8 in each category) were tested with a motion paradigm that generated an inter-aural centrifugal force of 0.36 G, resulting in a 20° tilt of the gravito-inertial force in the roll plane. We found that percepts of roll tilt developed slower in VM patients than in the two control groups, but that eye movement responses, including the shift in the eye's rotational axis, were equivalent in all three groups. These results demonstrate a change in vestibular perception in VM that is unaccompanied by changes in vestibular-mediated eye movements and suggest that either the brain's integration of canal and otolith signals or the dynamics of otolith responses are aberrant in patients with VM.

Vestibular migraine

During the last decades a new vestibular syndrome has emerged that is now termed vestibular migraine (VM). The main body of evidence for VM is provided by epidemiologic data demonstrating a strong association between migraine and vestibular symptoms. Today, VM is recognized as one of the most common causes of episodic vertigo. The clinical presentation of VM is heterogeneous in terms of vestibular symptoms, duration of episodes, and association with migrainous accompaniments. Similar to migraine, there is no clinical or laboratory confirmation for VM and the diagnosis relies on the history and the exclusion of other disorders. Recently, diagnostic criteria for VM have been elaborated jointly by the International Headache Society and the Bárány Society. Clinical examination of patients with acute VM has clarified that the vast majority of patients with VM suffer from central vestibular dysfunction. Findings in the interval may yield mild signs of damage to both the central vestibular and ocular motor system and to the inner ear. These interictal clinical signs are not specific to VM but can be also observed in migraineurs without a history of vestibular symptoms. How migraine affects the vestibular system is still a matter of speculation. In the absence of high-quality therapeutic trials, treatment is targeted at the underlying migraine.

Subclinical vestibular dysfunction in migraine patients: a preliminary study of ocular and rectified cervical vestibular evoked myogenic potentials

Background

Many studies have identified various vestibular symptoms and laboratory abnormalities in migraineurs. Although the vestibular tests may be abnormal, the changes may exist without vestibular symptoms. To date, vestibular-evoked myogenic potential (VEMP) has been the easiest and simplest test for measuring vestibular function in clinical practice. Cervical VEMP (cVEMP) represents a vestibulo-collic reflex, whereas ocular VEMP (oVEMP) reflects a vestibulo-ocular pathway. Therefore, we determined whether ocular and rectified cervical VEMPs differed in patients with migraine or tension type headache (TTH) and compared the results to controls with no accompanying vestibular symptoms.

Methods

The present study included 38 females with migraine without aura, 30 with episodic TTH, and 50 healthy controls without vestibular symptoms. oVEMP and cVEMP using a blood pressure manometer were recorded during a headache-free period. From the VEMP graphs, latency and amplitude parameters were analyzed, especially following EMG rectification in cVEMP.

Results

With respect to oVEMP, the migraine group exhibited significantly longer mean latencies of bilateral n1 and left p1 than the other groups (p < 0.05). Amplitudes of n1-p1 were lower than in other groups, but the difference did not reach statistical significance. In regards to cVEMP, p13 and n23 latencies and amplitudes after rectification did not differ significantly among groups.

Conclusions

An abnormal interictal oVEMP profile was associated with subclinical vestibular dysfunction in migraineurs, suggesting pathology within the vestibulo-ocular reflex. oVEMP is a more reliable measure than cVEMP to evaluate vestibular function in migraineurs, although results from the two tests in patients with migraine are complementary.

Central Integration of Canal and Otolith Signals is Abnormal in Vestibular Migraine

Vestibular migraine (VM), a common cause of vestibular symptoms within the general population, is a disabling and poorly understood form of dizziness. We sought to examine the underlying pathophysiology of VM with three studies, which involved the central synthesis of canal and otolith cues, and present preliminary results from each of these studies: (1) VM patients appear to have reduced motion perception thresholds when canal and otolith signals are modulated in a co-planar manner during roll tilt; (2) percepts of roll tilt appear to develop more slowly in VM patients than in control groups during a centrifugation paradigm that presents conflicting, orthogonal canal and otolith cues; and (3) eye movement responses appear to be different in VM patients when studied with a post-rotational tilt paradigm, which also presents a canal–otolith conflict, as the shift of the eye’s rotational axis was larger in VM and the relationship between the axis shift and tilt suppression of the vestibulo-ocular reflex differed in VM patients relative to control groups. Based on these preliminary perceptual and eye movement results obtained with three different motion paradigms, we present a hypothesis that the integration of canal and otolith signals by the brain is abnormal in VM and that this abnormality could be cerebellar in origin. We provide potential mechanisms that could underlie these observations, and speculate that one of more of these mechanisms contributes to the vestibular symptoms and motion intolerance that are characteristic of the VM syndrome.

Migraine and dizziness

PURPOSE OF REVIEW

Awareness of the importance of migraine in patients with symptoms of vestibular dysfunction is increasing. This article gives an overview of the multiple facets of the link between migraine and vestibular dysfunction.

RECENT FINDINGS

The vestibular and the headache community have published a consensual definition of vestibular migraine, which is an important step to promote research on the topic and the awareness of clinicians. Vestibular migraine is considered the most common cause of spontaneous recurrent vertigo. So far, the evidence for vestibular migraine has been mainly epidemiological, but the recent follow-up of a cohort over 9 years could show the robustness of the diagnosis over time.Additionally, migraine and vestibular dysfunction have multiple potential interactions and links through a range of comorbidities such as Menière's disease, benign paroxysmal positional vertigo, anxiety and motion sickness, which go beyond the diagnostic entity of vestibular migraine.

SUMMARY

The further refinement and wider acceptance of the diagnostic entity of vestibular migraine is an important development as it is one the most common vestibular disorders. But the relationship between migraine and vestibular dysfunction is complex and has many aspects beyond vestibular migraine.

Vestibular functioning and migraine: comparing those with and without vertigo to a normal population

Objective:

This study compared vestibular functioning in a migrainous vertigo group, a migraine without vertigo group and a control group. It was hypothesised that the migrainous vertigo group would perform worse in tests of vestibular function and gait than the other groups during a non-migrainous period.

Methods:

Sixty-six participants (22 per group) were assessed using the head shake sensory organisation test, the gaze stabilisation test, the dynamic visual acuity test and the functional gait assessment. Separate analyses of variance and planned pair-wise comparisons (alpha = 0.05) were performed.

Results:

There was a difference between the results of the non-migraine group and the two migraine groups for the gaze stabilisation pitch test (p < 0.003), in which the control group showed faster head movement. There were also group differences in functional gait (p < 0.0001); the control group scored highest and the migrainous vertigo group scored lowest. There were no differences in the vestibular spinal reflex and balance tests.

Conclusion:

These findings indicate underlying differences in the vestibular ocular reflexes and function of migraine sufferers compared with those who do not suffer migraines, but the difference is most pronounced for those with migrainous vertigo. This suggests that vestibular rehabilitation for migrainous vertigo should focus on vestibular ocular reflexes and functional retraining.

Clinical factors associated with prolonged recovery after superior canal dehiscence surgery

OBJECTIVE

To identify clinical factors associated with prolonged recovery after superior canal dehiscence surgery.

STUDY DESIGN

Retrospective review.

SETTING

Tertiary care academic medical center.

PATIENTS

Thirty-three patients that underwent surgery for SCDS were identified from a database of 140 patients diagnosed with SCD (2000-2010) at the Massachusetts Eye and Ear Infirmary (U.S.A.). The diagnosis of SCDS was based on clinical signs and symptoms, audiometric and vestibular testing and high-resolution temporal bone computed tomography.

INTERVENTION

For the primary repair, the superior canal was plugged in 31 patients through a middle fossa craniotomy approach and in 1 patient through a transmastoid approach. In 1 patient, the SCD was resurfaced through a middle fossa craniotomy approach.

MAIN OUTCOME MEASURES

Postoperative clinical signs and symptoms and factors that may influence duration of disequilibrium after surgery.

RESULTS

Thirty-three patients (15-71 yr; mean, 43 yr) underwent surgery for SCDS on 35 ears (2 bilateral). Mean follow-up was 28.7 months (range, 3 mo to 10 yr); 33 of 33 (100%) patients experienced initial improvement of the chief complaint. Three patients required revision surgery, improving symptoms in 2 patients. Six patients had dizziness lasting more than 4 months postoperatively, and all had bilateral SCD, migraines, and a dehiscence of 3 mm or greater.

CONCLUSION

Surgical plugging of SCD is an effective management option to provide long-term improvement of the chief complaint in SCDS patients. Patients with bilateral SCD, a history of migraines, and larger defects may be at risk of prolonged recovery and should be appropriately counseled.

Dynamic tilt thresholds are reduced in vestibular migraine

Vestibular symptoms caused by migraine, referred to as vestibular migraine, are a frequently diagnosed but poorly understood entity. Based on recent evidence that normal subjects generate vestibular-mediated percepts of head motion and reflexive eye movements using different mechanisms, we hypothesized that percepts of head motion may be abnormal in vestibular migraine. We therefore measured motion detection thresholds in patients with vestibular migraine, migraine patients with no history of vestibular symptoms, and normal subjects using the following paradigms: roll rotation while supine (dynamically activating the semicircular canals); quasi-static roll tilt (statically activating the otolith organs); and dynamic roll tilt (dynamically activating the canals and otoliths). Thresholds were determined while patients were asymptomatic using a staircase paradigm, whereby the peak acceleration of the motion was decreased or increased based on correct or incorrect reports of movement direction. We found a dramatic reduction in motion thresholds in vestibular migraine compared to normal and migraine subjects in the dynamic roll tilt paradigm, but normal thresholds in the roll rotation and quasi-static roll tilt paradigms. These results suggest that patients with vestibular migraine may have enhanced perceptual sensitivity (e.g. increased signal-to-noise ratio) for head motions that dynamically modulate canal and otolith inputs together.

The point prevalence of dizziness or vertigo in migraine--and factors that influence presentation

OBJECTIVE

To ascertain and characterize the point prevalence of dizziness or vertigo in migraineurs presenting for routine appointments at a specialty headache clinic.

BACKGROUND

Migraine, dizziness, and vertigo are all common in the general population, affecting 13%, 20-30%, and 5-10% respectively. Thereby, chance concurrence of migraine with either dizziness or vertigo would be expected in roughly 4% of the general population. It is the authors' clinical impression that severe attacks of migraine are far more commonly associated with these complaints than chance would predict.

METHODS

This is a prospective, cross-sectional study of 462 consecutive patients who presented for consultation at a specialty headache clinic over a 4-month period of time. During routine check-in procedures, patients were asked to report their headache pain on a 1-10 Likert scale. Patients were also asked to report if they were currently experiencing dizziness or vertigo. Responses to these questions were recorded along with vital signs. Diagnosis of migraine with or without aura was made by headache medicine specialists in accordance with International Classification of Headache Disorders--second edition criteria. Chi-square analysis was used to examine the prevalence of vertigo or dizziness in subjects with varying intensity of headache, and by history of aura.

RESULTS

Of the 425 evaluable subjects, 28% experienced aura. Subjects' average age was 43.8 years (range 15 to 76 years); 89.5% were female. At the time of evaluation, 72.4% of subjects reported some degree of ongoing headache pain and 15.7% reported concurrent dizziness or vertigo. The prevalence of dizziness or vertigo was twice as high (24.5% vs 12.1%) in migraine with aura compared to migraine without aura (P < .01), and prevalence increased with age (P < .05). There was a strong correlation between migraine pain and subjective complaint of vertigo (P < .001). When migraine pain was present at an intensity of 7 or greater (on a scale of 1-10), almost half of the subjects (47.5%) reported concomitant dizziness or vertigo.

CONCLUSIONS

Subjective complaints of dizziness or vertigo appear to be relatively common accompaniments of migraine, particularly migraine with aura, and prevalence increases with age. Disequilibrium symptoms have a strong and positive association with the severity of migraine pain. With co-occurrence higher than expected by chance, the relationship either reflects comorbidity or these symptoms may be part of the migraine presentation. With a point prevalence of 15.7%, and factors that link expression both to the intensity of migraine pain and to migraine aura, the authors believe that the true relationship may prove to be the latter.

Vestibular sensitivity in vestibular migraine: VEMPs and motion sickness susceptibility

Background: Vestibular migraine (VM) has gained recognition as a distinct clinical entity in recent years. The pathophysiology is unclear. Vestibular evoked myogenic potential (VEMP) is a validated method to test the vestibulocollic reflex and peripheral vestibular hypersensitivity to noise. The aim of our study was to evaluate the vestibular function and sensitivity in a series of VM patients in comparison to ordinary migraine (M) patient and healthy controls.

Methods: Thirty-seven patients diagnosed with VM according to the Neuhauser criteria, 32 migraineurs, and 30 healthy persons underwent VEMP testing (response and sound intensity threshold) and a motion sickness susceptibility questionnaire.

Results: We found absence of unilateral or bilateral VEMP response at 90  dB normal hearing level (nHL) in 44% of the VM patients, in 25% of the migraineurs, as compared to in 3% of the healthy controls ( p  =  0.001). The sound intensity threshold and latencies were similar in all the groups. Migraineurs (VM > M) reported more motion sickness than healthy controls ( p  =   0.006).

Conclusion: The results indicate more pathology in the VEMP circuitry in migraineurs than in healthy controls. We did not find support for peripheral vestibular hypersensitivity in terms of lower VEMP threshold among VM patients, but they are more sensitive for motion triggers than other migraineurs.