Regional homogeneity abnormalities affected by depressive symptoms in migraine patients without aura: a resting state study

Background

Bidirectional relationship between migraine and depression suggests that there might be some etiological risk factors shared. However, few studies investigated resting state abnormalities affected by depressive symptoms in migraine patients without aura (MWoA).

Materials and Methods

According to their self-rating depression scale (SDS) score, MWoA were divided into twenty in the SDS (+) (SDS > 49) group and 20 in the SDS (−) (SDS ≤ 49) group. Regional homogeneity (ReHo) method were employed to assess local features of spontaneous brain activity between 1) all MWoA and healthy controls, 2) each subgroup and healthy controls, and 3) SDS (−) group and SDS (+) group.

Results

Compared with healthy controls, decreased ReHo in similar regions were shown in the MWoA group and subgroups. It is noteworthy that the caudate showed increased ReHo in the SDS (−) group compared with healthy controls and the SDS (+) group. Moreover, the average ReHo values of the caudate in SDS (−) group were significantly positively correlated with duration of migraine.

Conclusions

Our results suggested that ReHo patterns in migraine patients may be affected by depressive symptoms and serve as a biomarker to reflect depression severity in MWoA.

Alterations of regional spontaneous neuronal activity and corresponding brain circuit changes during resting state in migraine without aura

Although previous resting-state studies have reported abnormal functional cerebral changes in patients with migraine without aura (MwoA), few have focused on alterations in both regional spontaneous neuronal activity and corresponding brain circuits in MwoA patients during rest. Eighteen MwoA patients and 18 age- and gender-matched healthy controls (HC) were recruited in the current study. Baseline cerebral alterations were investigated using amplitude of low-frequency fluctuation (ALFF) and region of interest (ROI)-based functional connectivity (FC) analyses. Compared with HC, MwoA patients showed decreased ALFF values in the left rostral anterior cingulate cortex (rACC) and bilateral prefrontal cortex (PFC) as well as increased ALFF values in the right thalamus. FC analysis also revealed abnormal FCs associated with these ROIs. In addition, ALFF values of the left rACC correlated with duration of disease in MwoA. Our findings could lead to a better understanding of intrinsic functional architecture of baseline brain activity in MwoA, providing both regional and brain circuit spontaneous neuronal activity properties.

Structural and functional abnormalities in migraine patients without aura

Migraine is a primary headache disorder characterized by recurrent attacks of throbbing pain associated with neurological, gastrointestinal and autonomic symptoms. Previous studies have detected structural deficits and functional impairments in migraine patients. However, researchers have failed to investigate the functional connectivity alterations of regions with structural deficits during the resting state. Twenty-one migraine patients without aura and 21 age- and gender-matched healthy controls participated in our study. Voxel-based morphometric (VBM) analysis and functional connectivity were employed to investigate the abnormal structural and resting-state properties, respectively, in migraine patients without aura. Relative to healthy comparison subjects, migraine patients showed significantly decreased gray matter volume in five brain regions: the left medial prefrontal cortex (MPFC), dorsal anterior cingulate cortex (dACC), right occipital lobe, cerebellum and brainstem. The gray matter volume of the dACC was correlated with the duration of disease in migraine patients, and thus we chose this region as the seeding area for resting-state analysis. We found that migraine patients showed increased functional connectivity between several regions and the left dACC, i.e. the bilateral middle temporal lobe, orbitofrontal cortex (OFC) and left dorsolateral prefrontal cortex (DLPFC). Furthermore, the functional connectivity between the dACC and two regions (i.e. DLPFC and OFC) was correlated with the duration of disease in migraine patients. We suggest that frequent nociceptive input has modified the structural and functional patterns of the frontal cortex, and these changes may explain the functional impairments in migraine patients.

Intrinsic brain network abnormalities in migraines without aura revealed in resting-state fMRI

BACKGROUND

Previous studies have defined low-frequency, spatially consistent intrinsic connectivity networks (ICN) in resting functional magnetic resonance imaging (fMRI) data which reflect functional interactions among distinct brain areas. We sought to explore whether and how repeated migraine attacks influence intrinsic brain connectivity, as well as how activity in these networks correlates with clinical indicators of migraine.

METHODS/PRINCIPAL FINDINGS

Resting-state fMRI data in twenty-three patients with migraines without aura (MwoA) and 23 age- and gender-matched healthy controls (HC) were analyzed using independent component analysis (ICA), in combination with a "dual-regression" technique to identify the group differences of three important pain-related networks [default mode network (DMN), bilateral central executive network (CEN), salience network (SN)] between the MwoA patients and HC. Compared with the HC, MwoA patients showed aberrant intrinsic connectivity within the bilateral CEN and SN, and greater connectivity between both the DMN and right CEN (rCEN) and the insula cortex - a critical region involving in pain processing. Furthermore, greater connectivity between both the DMN and rCEN and the insula correlated with duration of migraine.

CONCLUSIONS

Our findings may provide new insights into the characterization of migraine as a condition affecting brain activity in intrinsic connectivity networks. Moreover, the abnormalities may be the consequence of a persistent central neural system dysfunction, reflecting cumulative brain insults due to frequent ongoing migraine attacks.

Prostaglandin E(2) induces immediate migraine-like attack in migraine patients without aura

BACKGROUND

Prostaglandin E(2) (PGE(2)) has been suggested to play an important role in the pathogenesis of migraine. In the present experiment we investigated if an intravenous infusion of PGE(2) would induce migraine-like attacks in patients with migraine.

METHODS

Twelve patients with migraine without aura were randomly allocated to receive 0.4 µg/kg/min PGE(2) (Prostin(®)E2, dinoprostone) or placebo over 25 minutes in a two-way, crossover study. Headache intensity was recorded on a verbal rating scale, middle cerebral artery blood flow velocity (V(MCA)) was measured by transcranial Doppler (TCD) and diameter of the superficial temporal artery (STA) was obtained by c-series scan (Dermascan C).

RESULTS

In total, nine migraine patients (75%) experienced migraine-like attacks after PGE(2) compared to none after placebo (p = 0.004). Seven out of 9 (58%) patients reported the migraine-like attacks during the immediate phase (0-90 min) (p = 0.016). Only two patients experienced the delayed migraine-like attacks several hours after the PGE(2) infusion stop (p = 0.500). The V(MCA) decreased during the PGE(2) infusion (p = 0.005) but there was no significant dilatation of the STA (p = 0.850).

CONCLUSION

The migraine-like attacks during, and immediately after, the PGE(2) infusion contrast with those found in previous provocation studies, in which the other pharmacological compounds triggered the delayed migraine-like attacks several hours after the infusion. We suggest that PGE(2) may be one of the important final products involved in the generation of migraine attacks.

Regional homogeneity abnormalities in patients with interictal migraine without aura: a resting-state study

Previous studies have provided evidence of structural and task-related functional changes in the brains of patients with migraine without aura. Resting-state brain activity in patients with migraine provides clues to the pathophysiology of the disease. However, few studies have focused on the resting-state abnormalities in patients with migraine without aura. In the current study, we employed a data-driven method, regional homogeneity (ReHo), to analyze the local features of spontaneous brain activity in patients with migraine without aura during the resting state. Twenty-six patients with migraine without aura and 26 age-, education- and gender-matched healthy volunteers participated in this study. Compared with healthy controls, patients with migraine without aura showed a significant decrease in ReHo values in the right rostral anterior cingulate cortex (rACC), the prefrontal cortex (PFC), the orbitofrontal cortex (OFC) and the supplementary motor area (SMA). In addition, we found that ReHo values were negatively correlated with the duration of disease in the right rACC and PFC. Our results suggest that the resting-state abnormalities of these regions may be associated with functional impairments in pain processing in patients with migraine without aura. We hope that our results will improve the understanding of migraine.

Detection and discrimination of flicker contrast in migraine

AIMS

Flickering light is strongly aversive to many individuals with migraine. This study was designed to evaluate other abnormalities in the processing of temporally modulating visual stimulation.

METHODS

We measured psychophysical thresholds for detection of a flickering target and for the discrimination of suprathreshold flicker contrasts (increment thresholds) in 14 migraineurs and 14 healthy controls with and without prior adaptation to high-contrast flicker. Visual discomfort (aversion) thresholds were also assessed.

RESULTS

In the baseline (no adaptation) conditions, detection and discrimination thresholds did not differ significantly between groups. Following adaptation, flicker detection thresholds were elevated equivalently in both groups; however, discrimination thresholds were more strongly affected in migraineurs than in controls, showing greater elevation at moderate contrasts and greater threshold reduction (sensitisation) at high contrast (70%). Migraineurs also had significantly elevated discomfort scores, and these were significantly correlated with number of years with migraine.

DISCUSSION

We conclude that visual flicker not only causes discomfort but also exerts measurable effects on contrast processing in the visual pathways in migraine. The findings are discussed in the context of the existing literature on habituation, adaptation and contrast-gain control.

Patients with migraine with aura have increased flow mediated dilation

BACKGROUND

Endothelium-derived nitric oxide (NO) mediates the arterial dilation following a flow increase (i.e. flow-mediated dilation, FMD), easily assessed in the brachial artery. NO is also involved in cerebral hemodynamics and it is supposed to trigger vascular changes occurring during migraine. This study aimed at investigating whether migraine patients present an altered response to NO also in the peripheral artery system.

METHODS

We enrolled 21 migraineurs (10 with aura [MwA], 11 without aura [MwoA]), and 13 controls. FMD was evaluated with ultrasound in all subjects by measuring the percentage increase of the brachial artery diameter induced by hyperaemia reactive to sustained cuff inflation around the arm above systolic pressure. FMD values were then normalized for shear stress.

RESULTS

Normalized FMD values were higher in patients with MwA (28.5 10-2%.s) than in controls (9.0 10-2%.s) and patients with MwoA (13.7 10-2%.s) (p < 0.001). FMD was over the median value (19%) in 23.1% of controls, in 45.5% of the MwoA patients, and in 90% of the MwA patients.

CONCLUSIONS

Migraineurs with aura present an excessive arterial response to hyperaemia, likely as an effect of an increased sensitivity to endothelium-derived nitric oxide. This phenomenon observed peripherally might reflect similar characteristics in the cerebral circulation.

Somatosensory evoked potentials in children with migraine with aura and without aura

BACKGROUND

The Interictal abnormalities of cerebral information processing in migraine were found by studying different modality-specific evoked and event related potentials, mostly visual and auditory. In this study we focused on short-latency somatosensory evoked potentials (SEP) in children and adolescents suffering from migraine with and without aura.

MATERIAL AND METHODS

The study group consisted 111 of children and adolescents at the age of 7-18 years: 27 of them suffered from migraine with aura, 36 of them suffered from migraine without aura, 48 subjects have episodic tension-type headache. SEPs was performed interictally at least two days after the last headache attack.

RESULTS

There were no significant differences in the latency averages of SEP components between all migraneurs and tension-type headache subjects. However, N9 and N13 latency averages were significantly shorter in migraine without aura group compared with migraine with aura and tensiom type headaches. We did not find any significant correlations for either headache type between evoked potentials parametrs and illness duration, unilateral localisation of pain, migraine in family and aura.

CONCLUSIONS

In concert with similar studies in adult migraineurs, our findings showed no disturbances of somatosensory information processing in children with migraine with aura and without aura. The diagnosis of migraine in children actually remains predominantly based on medical history. However, electrophysiological techniques allow the study of some of the structures in vivo and enlarge our knowledge on controversial aspects of migraine pathophysiology.

Increased baroreflex sensitivity and heart rate variability in migraine patients

OBJECTIVES

We investigated whether spontaneous baroreflex sensitivity and heart rate variability (HRV) are different in migraine patients compared to healthy controls.

MATERIAL AND METHODS

Sixteen female migraine patients without aura aged 18-30 years and 14 age-matched healthy female controls were included. Continuous finger blood pressure and ECG were measured supine during paced breathing in the laboratory. Continuous finger blood pressure was measured the following 24-h period. Spontaneous baroreflex sensitivity (time-domain cross correlation baroreflex sensitivity) as well as HRV parameters were calculated.

RESULTS

Spontaneous baroreflex sensitivity measured in the 24-h period was increased in patients (20.6 ms/mmHg) compared to controls (15.7 ms/mmHg, P = 0.031). HRV parameters were increased during paced breathing in patients (P < 0.045).

CONCLUSIONS

The results suggest that central hypersensitivity in migraine also includes cardiovascular reactivity and may be important for the understanding of the mechanisms for the effect of antihypertensive drugs for migraine prophylaxis.

Migraine presenting as chronic facial pain

We report the case of a 44-year-old woman with chronic facial pain. She was treated with several analgesics, prophylactic medications and infiltrations, but all treatment modalities were ineffective. Finally, the diagnosis of medication-overuse headache complicating migraine without aura was made and an appropriate treatment was initiated. Migraine is a very common primary headache and rarely presents as isolated facial pain. Stimulation of the dura with activation of the trigeminovascular system can result in pain in any of the three divisions of the trigeminal nerve. This is the anatomic basis of migraine pain presenting as referred pain to the second division of the trigeminal nerve. The atypical presentation of migraine pain can easily lead to inappropriate treatment regimens.

Visual evoked potential and spatial frequency in migraine: a longitudinal study

OBJECTIVES

Reduced habituation of visual evoked potentials (VEP) has been reported in migraine. We aimed to study if preattack excitability changes were related to check size using a paired longitudinal design.

MATERIALS AND METHODS

Magnocellular and parvocellular functions were studied with monocular 31 and 62 checks in 33 adult migraine patients without aura (MwoA), 8 with aura (MA) and 31 controls. VEP was recorded in four blocks of 50 stimuli. N1P1 and P1N2 amplitudes were measured. Sessions were classified as preattack or interictal.

RESULTS

MA patients had significantly higher P1N2 and N1P1 amplitude than the controls and MwoA. VEP amplitude habituation was not found in controls. Migraine patients had significantly higher P1N2 amplitude before the attack compared with a paired interictal recording for large checks.

CONCLUSIONS

Cortical excitability is high in MA. Headache severity affects visual excitability. Increased P1N2 VEP amplitude before the attack suggests a cyclic decreased intracortical inhibition in extrastriate magnocellular pathways in migraine.

Jactatio extra-capitis and migraine suppression

Sleep often terminates migraine headaches, and sleep disorders occur with greater prevalence in individuals with chronic or recurrent headaches. Rhythmic head, limb or body movements are common in children before falling asleep, but they very rarely persist into adolescence and adulthood, or appear de novo later in life as sleep-related rhythmic movement disorders. A 22-year-old female with migraine without aura and history of early childhood pre-dormital body rocking (jactatio) discovered that unilateral slow rhythmic movements of her right foot greatly facilitated falling sound asleep while reclining. Sleep served every time to terminate her migraine attack. Rhythmic movements may serve on occasion as a therapeutic hypnotic maneuver in migraine sufferers.

[The mechanism of peripheral and central sensitization in migraine. A literature review]

Migraine attacks are characterized by unilateral throbbing, pulsating headache associated with nausea, vomiting, photophobia, phonophobia and allodynia. Peripheral sensitization is an acute, chemical-induced form of functional plasticity, which converts high-threshold nociceptors into low-threshold sensory neurons. This form of sensitization occurs when the nerve terminals (meningeal nociceptors) of the neurons of the trigeminal ganglion are soaked with the "inflammatory" soup (prostaglandin E2, bradykinin, serotonin and cytokines) along the vasculature of the cerebral dura mater. Peripheral sensitization in migraine attacks is explained clinically by intracranial hypersensitivity (the headache worsens during coughing or physical activity) and by a throbbing element in the pain of migraine (sensitized nociceptors become hyperresponsive to the otherwise innocuous and unperceived rhythmic fluctuation in intracranial pressure produced by normal arterial pulsation). The essence of central sensitization is that the second-order neurons in the trigeminocervical complex become hyperexcitable. The altered behavior of the second-order neurons is based on the increased glutamate sensistivity of the NMDA receptors and the neuronal nitric oxide synthase activity stimulated by nitric oxide. This process is explained clinically by face and scalp ollodynia and by neck stiffness (extracranial tenderness).

The middle meningial artery during a migraine attack: 3T magnetic resonance angiography study

We performed 3T magnetic resonance angiography (MRA) during a spontaneous migraine attack. The patient was a 42-year-old woman migraineur diagnosed by the IHS criteria. The change of the middle meningial artery (MMA) was measured on the axial brain images using MATLAB for three phases (attack-free period, during an attack, a period after medication). There were no dramatic changes of vasodilation in the MMA during the attack (2.0 mm), attack-free period (diameter 1.9 mm), or period after medication (1.7 mm), resembling extrapolations of observations in experimental animal models. This finding suggests that the dramatic vasomotion might not be associated with migraine pathophysiology.

The effects of magnesium prophylaxis in migraine without aura

There are inconsistent findings about the efficacy of magnesium in the prophylaxis of migraine attacks and there is no study of magnesium prophylaxis focused on migraine subtypes without aura. In this double blind, randomized, placebo controlled study; we tried to evaluate the prophylactic effects of oral magnesium in migraine patients without aura. The prophylactic effects of 600 mg/day oral magnesium citrate supplementation were assessed by means of clinical evaluation, visual evoked potential and statistical parametric mapping of brain single photon emission computerized tomography before and after a 3 month treatment period. The results of 30 patients with migraine without aura (20-55 years old with 2-5 migraine attacks per month) on magnesium treatment were compared with those of 10 patients with similar properties on placebo treatment. Migraine attack frequency, severity and P1 amplitude in visual evoked potential examination decreased after magnesium treatment with respect to pretreatment values (p < 0.001). In a comparison of the effects of magnesium treatment with those of placebo, post/pretreatment ratios of migraine attack frequency, severity and P1 amplitude in Mg treatment group were found to be significantly lower than those in placebo treatment group (attack frequency p = 0.005, attack severity p < 0.001, P1 amplitude p < 0.05). Cortical blood flow in inferolateral frontal (p < 0.001), inferolateral temporal (p = 0.001) and insular regions (p < 0.01) increased significantly after magnesium treatment with respect to the pretreatment; while such significant changes of cortical blood flow were not observed with placebo treatment. These results have made us think that magnesium is a beneficial agent in prophylaxis of migraine without aura and might work with both vascular and neurogenic mechanisms.

Clinical correlates of phosphene perception in migraine without aura: An Asian study

INTRODUCTION

Although controversy exists with regard to the presence of hypoexcitability versus hyperexcitability of the visual cortex in migraine patients, there remain a group who do not perceive phosphenes (P-). However, its clinical implications have not been systematically addressed. In this study, we hypothesize that P- patients classified as migraine without aura (MO) have distinct clinical features.

METHODS

Twenty-nine Asian MO patients (7 men; mean age: 44; median: 45; range: 25 to 65) were consecutively entered into the study. Visual cortex transcranial magnetic stimulation (TMS) was performed in the migraine interictum.

RESULTS

Of the 19 patients, 19 (66%) were able to perceive phosphenes (P+), while 10 (34%) were not able to after repeated TMS (P-). P- patients had significantly higher headache frequency (p=0.008) and pain score (p=0.002) compared with P+ patients. In addition, there was significant positive correlation of phosphene threshold with pain score (r=0.52, p=0.02) in P+ patients. There was no significant difference between P+ and P- patients in terms of age (t-test, p=0.6).

CONCLUSIONS

Our study is inkeeping with the hypothesis that interictal visual cortex excitability is reduced in relation to the severity of migraine in Asian MO patients, and lack of phosphene perception may be related to significantly elevated thresholds beyond the output of TMS stimulators.

Massaging over the greater occipital nerve reduces the intensity of migraine attacks: evidence for inhibitory trigemino-cervical convergence mechanisms

Activation of the trigemino-cervical system constitutes one of the first steps in the genesis of migraine. The objective of this study was to confirm the presence of trigemino-cervical convergence mechanisms and to establish whether such mechanisms may also be of inhibitory origin. We describe a case of a 39-years-old woman suffering from episodic migraine who showed a significant improvement in her frontal headache during migraine attacks if the greater occipital nerve territory was massaged after the appearance of static mechanical allodynia (cortical sensitization). We review trigemino-cervical convergence and diffuse nociceptive inhibitory control (DNIC) mechanisms and suggest that the convergence mechanisms are not only excitatory but also inhibitory.

[Observation on the therapeutic effect of ear point combined therapy on common migraine at the remission stage and effects on plasma CGRP and ET in the patient]

OBJECTIVE

To probe into the therapeutic effect of ear point combined therapy on common migraine at the remission stage and the mechanism.

METHODS

Thirty-two cases of common migraine at the remission stage were treated with ear point combined therapy, including blood-letting at ear back, injection of autoblood into Fengchi (GB 20), Yanglingquan (GB 34), and pricking at ear points Nie, Yi-dan (pancreas and gallbladder), Shenmen, etc.. Clinical therapeutic effect was evaluated at the end of one therapeutic course, and calcitonin gene-related peptide (CGRP) and endotheline (ET) were detected before and after treatment, and the CGRP and ET contents were compared with those in 22 normal persons.

RESULTS

The effective rate was 78.1% (P<0.001), CGRP and ET contents had very significant changes after treatment (P<0.01), and CGRP and ET showed negative correlativity (P<0.05).

CONCLUSION

The ear point combined therapy can regulates the balance between the plasma CGRP and ET in the patient of common migraine and improve vasodilative, vasoconstrictive and endothelial fuctions in the brain, hence stopping pain.

Effects of remote cutaneous pain on trigeminal laser-evoked potentials in migraine patients

The present study aimed to evaluate heat pain thresholds and evoked potentials following CO(2) laser thermal stimulation (laser-evoked potentials, LEPs), during remote application of capsaicin, in migraine patients vs. non-migraine healthy controls. Twelve outpatients suffering from migraine without aura were compared with 10 healthy controls. The LEPs were recorded by 6 scalp electrodes, stimulating the dorsum of the right hand and the right supraorbital zone in basal condition, during the application of 3% capsaicin on the dorsum of the left hand and after capsaicin removal. In normal subjects, the laser pain and the N2-P2 vertex complex obtained by the hand and face stimulation were significantly reduced during remote capsaicin application, with respect to pre-and post-capsaicin conditions, while in migraine LEPs and laser pain were not significantly modified during remote painful stimulation. In migraine a defective brainstem inhibiting control may coexist with cognitive factors of focalised attention to facial pain, less sensitive to distraction by a second pain.

Impairment in Color Perception in Migraine With and Without Aura

OBJECTIVE

To assess visual perception in 40 patients suffering from migraine with aura (MA), 40 patients suffering from migraine without aura (MO), and 40 controls.

BACKGROUND

Visual perception abnormalities are a common feature in both MA and MO.

METHODS

We performed luminance and color central perimetry. Black and white pattern reversal visual-evoked potentials were also assessed.

RESULTS

Luminance perimetry was similar in patients and controls. Color perimetry instead revealed an impairment in the perception of red ("quantitative perception index") in migraine patients; this impairment was more pronounced in patients with MA (P < .001) than in those with MO (P < .05) and was related to the degree of photophobia recorded before testing. A subgroup of MO patients who had a migraine attack shortly after being tested also displayed a marked impairment in the perception of blue. This subgroup of patients had a statistically significant (P < .001) lower perception of blue than the rest of the MO patients, who had a migraine attack later; they also had a high degree of unpleasant perceptions after testing. Black and white visual evoked potentials were similar in patients and controls.

CONCLUSION

The impairment in visual perception of red, which was more marked in MA than in MO patients, may be related to the degree of photophobia recorded before testing. The reduced perception of blue, which only occurred in a subgroup of MO patients in the premonitory phase of the migraine attack, probably occurs through mechanisms that involve dopaminergic function. We cannot exclude the possibility that the visual stimulations induced the migraine attack in this subgroup of MO patients shortly after they were tested.

Transcranial direct current stimulation reveals inhibitory deficiency in migraine

The issue of interictal excitability of cortical neurons in migraine patients is controversial: some studies have reported hypo-, others hyperexcitability. The aim of the present study was to observe the dynamics of this basic interictal state by further modulating the excitability level of the visual cortex using transcranial direct current stimulation (tDCS) in migraineurs with and without aura. In healthy subjects anodal tDCS decreases, cathodal stimulation increases transcranial magnetic stimulation (TMS)-elicited phosphene thresholds (PT), which is suggested as a representative value of visual cortex excitability. Compared with healthy controls, migraine patients tended to show lower baseline PT values, but this decrease failed to reach statistical significance. Anodal stimulation decreased phosphene threshold in migraineurs similarly to controls, having a larger effect in migraineurs with aura. Cathodal stimulation had no significant effect in the patient groups. This result strengthens the notion of deficient inhibitory processes in the cortex of migraineurs, which is selectively revealed by activity-modulating cortical input.