References of "Lisicki Martinez, Marco"
     in
Bookmark and Share    
Full Text
See detailDeterminants and consequences of abnormal visual cortex responsiveness in migraine without aura
Lisicki Martinez, Marco ULiege

Doctoral thesis (2018)

La migraine est une maladie multifactorielle complexe, qui résulte de l'interaction entre une prédisposition génétique et un environnement facilitant. La majeure partie de l' information venant de notre ... [more ▼]

La migraine est une maladie multifactorielle complexe, qui résulte de l'interaction entre une prédisposition génétique et un environnement facilitant. La majeure partie de l' information venant de notre entourage nous atteint via le système visuel, ce qui fait de la vision la modalité sensorielle la plus développée chez l'Homme et celle qui met en jeu les aires cérébrales les plus tendues. Un faisceau de données cliniques et expérimentales a montré que les patients migraineux sont hyper-réactifs à la stimulation visuelle, mais les déterminants de ce phénomène restent méconnus. De plus, bien qu'étroitement associée à la migraine, l‟hyper-réactivité visuelle n'est ni suffisante, ni nécessaire pour développer la, maladie ce qui suggère l'existence de mécanismes physiopathologiques additionnels. Dans cette thèse nous avons analysé des facteurs environnementaux, métaboliques, anatomo-fonctionnels, et neurochimiques liés à la réactivité visuelle chez les migraineux, et la possible implication de leur interaction dans la pathogénie de la maladie. Pour ce faire, nous avons réalisé une série d‟études neurophysiologiques et de neuroimagerie qui explorent des aspects distincts de la physiologie du cerveau. Les résultats montrent que (1) une part de la variabilité interindividuelle de la réactivité visuelle peut être expliquée par des influences environnementales; (2) l‟hyper-réactivité visuelle dans la migraine est le résultat d'un déséquilibre complexe entre les mécanismes qui favorisent une perception renforcée, et ceux qui protègent contre une surcharge sensorielle; (3) la réserve métabolique au niveau cortical est insuffisante face à la demande énergétique accrue due à l'hyper-réactivité visuelle. Ces résultats illustrent la complexité des mécanismes responsables de l'hyperréactivité visuelle dans la migraine, améliorent notre compréhension de la physiopathologie de cette maladie, et ouvrent la voie à des axes de recherche innovants. [less ▲]

Detailed reference viewed: 37 (4 ULiège)
Full Text
Peer Reviewed
See detailEvidence of an increased neuronal activation-to-resting glucose uptake ratio in the visual cortex of migraine patients: a study comparing 18FDG-PET and visual evoked potentials
Lisicki Martinez, Marco ULiege; D'Ostilio, Kevin; Coppola, Gianluca et al

in Journal of Headache and Pain (2018)

Background: Migraine attacks might be triggered by a disruption of cerebral homeostasis. During the interictal period migraine patients are characterized by abnormal sensory information processing, but ... [more ▼]

Background: Migraine attacks might be triggered by a disruption of cerebral homeostasis. During the interictal period migraine patients are characterized by abnormal sensory information processing, but this functional abnormality may not be sufficient to disrupt the physiological equilibrium of the cortex unless it is accompanied by additional pathological mechanisms, like a reduction in energetic reserves. The aim of this study was to compare resting cerebral glucose uptake (using positron emission tomography (18fluorodeoxyglucose-PET)), and visual cortex activation (using visual evoked potentials (VEP)), between episodic migraine without aura patients in the interictal period and healthy volunteers. Methods: Twenty episodic migraine without aura patients and twenty healthy volunteers were studied. 18FDG-PET and VEP recordings were performed on separate days. The overall glucose uptake in the visual cortex-to-VEP response ratio was calculated and compared between the groups. Additionally, PET scan comparisons adding area under the VEP curve as a covariate were performed. For case-wise analysis, eigenvalues from a specific region exhibiting significantly different FDG-PET signal in the visual cortex were extracted. Standardized glucose uptake values from this region and VEP values from each subject were then coupled and compared between the groups. Results: The mean area under the curve of VEP was greater in migraine patients compared to healthy controls. In the same line, patients had an increased neuronal activation-to-resting glucose uptake ratio in the visual cortex. Statistical parametric mapping analysis revealed that cortical FDG-PET signal in relation to VEP area under the curve was significantly reduced in migraineurs in a cluster extending throughout the left visual cortex, from Brodmann’s areas 19 and 18 to area 7. Within this region, case-wise analyses showed that a visual neuronal activation exceeding glucose uptake was present in 90% of migraine patients, but in only 15% of healthy volunteers. Conclusion: This study identifies an area of increased neuronal activation-to-resting glucose uptake ratio in the visual cortex of migraine patients between attacks. Such observation supports the concept that an activity-induced rupture of cerebral metabolic homeostasis may be a cornerstone of migraine pathophysiology. This article has been selected as the winner of the 2018 Enrico Greppi Award. The Enrico Greppi Award is made to an unpublished paper dealing with clinical, epidemiological, genetic, pathophysiological or therapeutic aspects of headache. Italian Society for the Study of Headaches (SISC) sponsors this award, and the award is supported through an educational grant from Teva Neuroscience. This article did not undergo the standard peer review process for The Journal of Headache and Pain. The members of the 2018 Enrico Greppi Award Selection Committee were: Francesco Pierelli, Paolo Martelletti, Lyn Griffiths, Simona Sacco, Andreas Straube and Cenk Ayata. [less ▲]

Detailed reference viewed: 66 (7 ULiège)
Full Text
Peer Reviewed
See detailBrain correlates of single trial visual evoked potentials in migraine: more than meets the eye.
Lisicki Martinez, Marco ULiege; D’Ostilio, Kevin; Coppola, Gianluca et al

in Frontiers in Neurology (2018)

Background: Using conventional visual evoked potentials (VEPs), migraine patients were found to be hyperresponsive to visual stimulus. Considering that a significant portion of neuronal activity is lost ... [more ▼]

Background: Using conventional visual evoked potentials (VEPs), migraine patients were found to be hyperresponsive to visual stimulus. Considering that a significant portion of neuronal activity is lost for analysis in the averaging process of conventional VEPs, in this study we investigated visual evoked responses of migraine patients and healthy volunteers using a different approach: single trial analysis. This method permits to preserve all stimulus-induced neuronal activations, whether they are synchronized or not. In addition, we used MRI voxel-based morphometry to search for cortical regions where gray matter volume correlated with single trial (st) VEP amplitude. Finally, using resting-state functional MRI, we explored the connectivity between these regions. Results: stVEP amplitude was greater in episodic migraine patients than in healthy volunteers. Moreover, in migraine patients it correlated positively with gray matter volume of several brain areas likely involved in visual processing, mostly belonging to the ventral attention network. Finally, resting state functional connectivity corroborated the existence of functional interactions between these areas and helped delineating their directions. Conclusions: st-VEPs appear to be a reliable measure of cerebral responsiveness to visual stimuli. Mean st-VEP amplitude is higher in episodic migraine patients compared to controls. Visual hyper-responsiveness in migraine involves several functionally-interconnected brain regions, suggesting that it is the result of a complex multi-regional process coupled to stimulus driven attention systems rather than a localized alteration. [less ▲]

Detailed reference viewed: 41 (2 ULiège)
Full Text
Peer Reviewed
See detailIncreased functional connectivity between the right temporo-parietal junction and the temporal poles in migraine without aura
Lisicki Martinez, Marco ULiege; D'Ostilio, Kevin; Coppola, Gianluca et al

in Cephalalgia Reports (2018)

Rather than a localized alteration, increased visual reactivity in migraine patients seems to result from a complex interaction between several brain structures, mostly involving the ventral attention ... [more ▼]

Rather than a localized alteration, increased visual reactivity in migraine patients seems to result from a complex interaction between several brain structures, mostly involving the ventral attention network. The hub of this network is the right temporo-parietal junction. In this report, complementing our previous findings, we describe the differences in seed to-voxel resting-state functional connectivity seeded in the right temporo-parietal junction (right angular gyrus) between migraine patients and healthy controls. Resting-state functional MRIs of episodic migraine without aura patients in the interictal period (n ¼ 19) and matched healthy controls (n ¼ 19) were analysed. With the seed placed in the right temporo-parietal junction (right angular gyrus), seed-to-voxel connectivity was compared between groups. Electrophysiological, voxel-based morphometry (both groups) and specific region of interest (ROI)-to-ROI functional connectivity (migraine patients) data have already been published. Migraine patients showed a higher positive interaction between the right temporo-parietal junction and both temporal poles and a higher negative interaction between this same region and bilateral areas of the visual cortex. On the basis of our results, and because of their established properties as multisensory integration hubs, it is likely that the right temporo-parietal junction and both temporal poles are involved in the altered processing of sensory stimulus commonly observed in migraine patients. Therefore, more attention should be paid to these regions for migraine research in the future. [less ▲]

Detailed reference viewed: 50 (7 ULiège)
Full Text
Peer Reviewed
See detailMigraine triggers and habituation of visual evoked potentials
Lisicki Martinez, Marco ULiege; Ruiz-Romagnoli, Emiliano; Piedrabuena, Raul et al

in Cephalalgia (2018)

Background: Identifying specific subsets of patients within the clinical spectrum of migraine could help in personalizing migraine treatment. Profiling patients by combining clinical characteristics and ... [more ▼]

Background: Identifying specific subsets of patients within the clinical spectrum of migraine could help in personalizing migraine treatment. Profiling patients by combining clinical characteristics and neurophysiological biomarkers is largely unexplored. We studied the association between migraine attack triggers and habituation of visual evoked potentials. Methods: We personally interviewed 25 patients about their migraine triggers following a structured list, and measured the N1-P1 habituation slope over six blocks of 100 averaged pattern-reversal VEP afterwards. Results: The mean number of triggers per patient was 4.52 1.42. Habituation slopes differed significantly between subjects who reported stress as a migraine trigger (deficient VEP habituation) and subjects who did not (preserved VEP habituation). For the remaining categories, the mean amplitude slope was always positive, indicating deficient habituation, and was not significantly different between subgroups. Conclusions: Migraine patients not reporting perceived stress as a trigger for their attacks might constitute a distinct clinic-physiological subset within the migraine spectrum. [less ▲]

Detailed reference viewed: 75 (6 ULiège)
Full Text
Peer Reviewed
See detailSunlight irradiance and habituation of visual evoked potentials in migraine: The environment makes its mark
Lisicki Martinez, Marco ULiege; D'Ostilio, Kevin; Erpicum, Michel ULiege et al

in Cephalalgia (2017)

Background Migraine is a complex multifactorial disease that arises from the interaction between a genetic predisposition and an enabling environment. Habituation is considered as a fundamental adaptive ... [more ▼]

Background Migraine is a complex multifactorial disease that arises from the interaction between a genetic predisposition and an enabling environment. Habituation is considered as a fundamental adaptive behaviour of the nervous system that is often impaired in migraine populations. Given that migraineurs are hypersensitive to light, and that light deprivation is able to induce functional changes in the visual cortex recognizable through visual evoked potentials habituation testing, we hypothesized that regional sunlight irradiance levels could influence the results of visual evoked potentials habituation studies performed in different locations worldwide. Methods We searched the literature for visual evoked potentials habituation studies comparing healthy volunteers and episodic migraine patients and correlated their results with levels of local solar radiation. Results After reviewing the literature, 26 studies involving 1291 participants matched our inclusion criteria. Deficient visual evoked potentials habituation in episodic migraine patients was reported in 19 studies. Mean yearly sunlight irradiance was significantly higher in locations of studies reporting deficient habituation. Correlation analyses suggested that visual evoked potentials habituation decreases with increasing sunlight irradiance in migraine without aura patients. Conclusion Results from this hypothesis generating analysis suggest that variations in sunlight irradiance may induce adaptive modifications in visual processing systems that could be reflected in visual evoked potentials habituation, and thus partially account for the difference in results between studies performed in geographically distant centers. Other causal factors such as genetic differences could also play a role, and therefore well-designed prospective trials are warranted. [less ▲]

Detailed reference viewed: 53 (9 ULiège)
Full Text
Peer Reviewed
See detailFamilial history of migraine influences habituation of visual evoked potentials
Lisicki Martinez, Marco ULiege; Ruiz-Romagnoli, Emiliano; D'Ostilio, Kevin ULiege et al

in Cephalalgia (2017)

Background: Lack of habituation of visual evoked potentials (VEP) is a common finding in migraine patients between attacks. Previous studies have suggested an electrophysiological familial aggregation ... [more ▼]

Background: Lack of habituation of visual evoked potentials (VEP) is a common finding in migraine patients between attacks. Previous studies have suggested an electrophysiological familial aggregation pattern associated with migraine. The aim of this study was to evaluate the influence of a positive familial history of migraine on VEP amplitude and habituation. Methods: We recorded six blocks of 100 VEP during continuous pattern-reversal stimulation in 30 patients with migraine between attacks (MO) and in 30 healthy volunteers, of whom 15 had a first-degree relative suffering from migraine (HVm) and 15 had not (HV). Results: Both MO and HVm had a significant deficit of VEP habituation and similarly reduced N1-P1 first block amplitudes, compared to HV (habituation slope: MO ¼ 0.033, HVm ¼ 0.021, HV ¼ 0.025, HV vs. MO p ¼ 0.002, HV vs. HVm p ¼ 0.036; mean N1-P1 amplitude in the first block: MO ¼ 9.08 mV, HVm ¼ 9.29 mV, HV ¼ 12.19 mV. HV vs. MO p ¼ 0.041, HV vs. HVm p ¼ 0.076). The first block N1-P1 amplitude was negatively correlated with the habituation slope for both MO (r ¼ .44, p ¼ 0.015) and HVm (r ¼ .56, p ¼ 0.031) while no significant correlation was found in HV (r ¼ .17, p ¼ 0.53). There were no differences in VEP latencies between the groups. Conclusions: Our study suggests that lack of habituation of visual evoked potentials is probably a genetically determined endophenotypic trait that is associated with both migraine and migraine susceptibility. We hypothesize that genetic diversity of populations could account for some of the discrepancies between electrophysiological studies performed in migraine and for interindividual variations among the subgroups. [less ▲]

Detailed reference viewed: 47 (10 ULiège)
Full Text
Peer Reviewed
See detailDistinct cerebral metabolic patterns related to high pain sensitivity in episodic or chronic migraine patients and healthy volunteers
D'Ostilio, Kevin ULiege; Lisicki Martinez, Marco ULiege; Schoenen, Jean ULiege et al

in Frontiers in Aging Neuroscience (2016, July)

Introduction Allodynia, i.e. pain evoked by a non-painful stimulus, is prevalent in chronic pain and in migraine where it augments with disease severity and chronicity [1]. Central sensitization is ... [more ▼]

Introduction Allodynia, i.e. pain evoked by a non-painful stimulus, is prevalent in chronic pain and in migraine where it augments with disease severity and chronicity [1]. Central sensitization is thought to be the culprit [2]. It is not known, however, which central areas are involved. The aim of the present study was to evaluate whether brain metabolism in subjects that are more sensitive to pain is different between migraine patients and healthy controls. Subjects and methods Quantitative heat sensory testing on the forehead and 18FDG-PET were performed in 55 subjects: 20 healthy volunteers (HV, 21-59 years, 5M), 21 patients with episodic migraine in the interictal phase (MO, age range: 20-63 years, 5M) and 14 patients with chronic migraine (CM, age range: 22-62 years, 1M). The 3 cohorts were subdivided according to the median heat pain threshold into subgroups with low and high pain thresholds. PET results were compared between these subgroups in each cohort. Data analyses were restricted to areas of the pain/salience matrix. Results There was no significant difference in heat pain thresholds between HV (median: 43.7 °C), MO median: 44.2°C) and CM (median: 43.3°C) (p=0.64). In an SPM-ANOVA, a contrast modelling the potential gradual effect of increased differences in pain sensitivity in relation to disease severity showed significant metabolic changes in bilateral thalamus and midbrain (p < 0.001). Additional analyses revealed that hypometabolic areas in subgroups with a low heat pain threshold differed between HV (anterior cingulate and somatosensory cortices), MO (lower pons and somatosensory cortex) and CM (midbrain and thalamus) (Figure 1). Conclusion Overall migraine patients do not have reduced heat pain thresholds. However, hypometabolic areas related to high thermal pain sensitivity are strictly cortical in HV, but comprise the pons in episodic migraine and are restricted to midbrain and thalamus in chronic migraine. The distinct central correlates of heat pain sensitivity in migraine patients might therefore represent a biomarker of migraine and its chronification. Legend to figure Figure 1. Hypometabolic areas in low pain threshold subgroups in HV (green), MO (orange) and CM (red). p < 0.01 for display purpose. Résumé en Français: Titre: Métabolisme cérébral distinct en relation avec la sensibilité à la douleur entre sujets sains, migraine épisodique et migraine chronique. Les migraineux ont une sensibilité anormale à la douleur. Les mécanismes cérébraux en sont inconnus. Nous avons comparé le métabolisme cérébral chez des sujets sains et chez des migraineux épisodiques ou chroniques et correlé les résultats avec le seuil douloureux. Les aires cérébrales hypométaboliques liées à un seuil douloureux bas diffèrent entre groupes: régions corticales chez les sujets sains, aires corticales et sous-corticales dans la migraine épisodique, régions sous-corticales dans la migraine chronique .Le contrôle central de la douleur semble modifié distinctement dans les formes de migraine, ce qui pourrait en constituer un biomarqueur et avoir des implications thérapeutiques. [less ▲]

Detailed reference viewed: 123 (2 ULiège)
Peer Reviewed
See detailAnodal transcranial direct stimulation (tDCS) targeting the anterior cingulate gyrus for the preventive treatment of chronic cluster headache: a proof of concept trial.
MAGIS, Delphine ULiege; D'Ostilio, Kevin ULiege; Cosseddu, Anna et al

Poster (2016, April)

Background There is a need for better treatments in chronic cluster headache (CCH). In responders to percutaneous occipital nerve stimulation, the subgenual anterior cingulate gyrus (sACG) was found ... [more ▼]

Background There is a need for better treatments in chronic cluster headache (CCH). In responders to percutaneous occipital nerve stimulation, the subgenual anterior cingulate gyrus (sACG) was found hypermetabolic (Magis et al. 2011). We reasoned that activation of this area by transcranial neurostimulation could be effective in CCH. Aim To explore the preventive effect of anodal (i.e. activating) transcranial direct current stimulation (tDCS) targeting the anterior cingulate gyrus in CCH patients. Method & subjects Difficult-to-treat CCH patients with a stable preventive drug regimen applied tDCS (2mA) interictally in 20-minute daily sessions for 4 weeks with the anode positioned over the forehead (FpZ), the cathode over the C7 spinous process. Therapeutic effects were monitored with paper diaries. Results Nineteen patients were enrolled up to now. In 13 patients who completed the trial, mean weekly attack frequency decreased by 38% after 4 weeks of daily stimulation (W-test: p = 0.002). The 50% responder rate was 54%. Patients (n=12) reported an improvement in headache impact, as shown by 5-point decrease in the mean HIT-6 score (from 67 to 62, p = 0.02). In 10 patients who were followed up after the treatment period, the benefit remained stable up to 4 weeks after the last stimulation. The first 3 enrolled patients had superficial skin burns under the adhesive cathode electrode. Sponge electrodes were therefore used in all subsequent patients without any adverse effect. Conclusion Anodal tDCS targeting the anterior cingulate gyrus seems promising for the preventive treatment of chronic cluster headache as suggested by this ongoing proof-of-concept trial. Use of adhesive electrodes is not recommended. [less ▲]

Detailed reference viewed: 69 (4 ULiège)
Peer Reviewed
See detailNon-invasive vagus nerve stimulation with the gammaCore® in healthy subjects: is there electrophysiological evidence for activation of vagal afferents ?
Schoenen, Jean ULiege; NONIS, Romain ULiege; D'Ostilio, Kevin ULiege et al

Poster (2016, April)

Abstract: Background Non-invasive vagus nerve stimulation (nVNS) with the gammaCore® improves migraine and cluster headache. Animal experiments suggest that nVNS acts via stimulation of vagal afferents ... [more ▼]

Abstract: Background Non-invasive vagus nerve stimulation (nVNS) with the gammaCore® improves migraine and cluster headache. Animal experiments suggest that nVNS acts via stimulation of vagal afferents, but proof in humans is lacking. Vagal somatosensory evoked potentials (vSEP) are identified after invasive VNS or transcutaneous stimulation of auricular vagal branches, but late components could be muscle artifacts. Objective To search in healthy volunteers for reliable vSEP during nVNS with the gammaCore® Methods In 12 healthy subjects (7males) evoked potentials were recorded at A1/A2 (ref Cz) and C3/C4 (ref F3/F4) during 2-minute stimulation over left/right cervical vagus nerve with the gammaCore® (25Hz, 6-24V) and during stimulation over the inner tragus with a monopolar stimulator (2Hz, 50 stimuli, mean intensity 8mA). Results We identified 3 reproducible peaks P1, N1, P2 in 10 patients on the side of the gammaCore® stimulation at mean latencies of 2.05ms, 5.20ms and 9.13ms. P1-N1 amplitude increased significantly (p<0.01) with increasing voltage from 0.04μV to 0.52μV (C3/C4) and from 0.13µV to 2.04μV (A1/A2) respectively at 10V and 30V. Inner tragus stimulation elicited P1, N1, P2 peaks with shorter mean latencies (2.21ms, 3.72ms, 5.71ms) and a mean P1-N1 amplitude (A1/A2) of 5.0µV. When the gammaCore® was placed over the sternocleidomastoid muscle, there were no reproducible evoked potentials. Conclusion Non-invasive transcutaneous stimulation of the cervical vagus nerve with the gammaCore® elicits evoked potentials similar to those found with implanted electrodes or stimulation of Arnold’s nerve in the outer ear. The gammaCore®-evoked potentials increase in amplitude with stimulation intensity and disappear when the stimulator is positioned over neck muscles, suggesting that they are not muscle artifacts. Their short latency is compatible with their generation at the level of the foramen jugulare. The therapeutic effects reported with the gammaCore® in primary headaches can thus be mediated by genuine activation of vagus nerve afferents. [less ▲]

Detailed reference viewed: 129 (4 ULiège)
Full Text
Peer Reviewed
See detailMETABOLIC CHANGES IN THE MIGRAINE BRAIN IN RELATION TO AGEING AND DISEASE LOAD
D'Ostilio, Kevin ULiege; Lisicki Martinez, Marco ULiege; NONIS, Romain ULiege et al

in Cephalalgia (2016), 36(1S), 59

Introduction: Migraine prevalence tends to decrease with advancing age. Morphological and functional brain changes occuring in migraine could be secondary to repeated attacks and/or to abnormal sensory ... [more ▼]

Introduction: Migraine prevalence tends to decrease with advancing age. Morphological and functional brain changes occuring in migraine could be secondary to repeated attacks and/or to abnormal sensory processing. In normal ageing, brain modifications could traduce a progressive refinement to cope with the environment, associated with a reduction in the complexity of brain connections. We hypothesized that metabolism in various brain regions might be differentially modified by age in migraine patients. Materials and methods: Forty-one subjects underwent a FDG-PET scan: 21 patients with interictal episodic migraine without aura (MO, age range: 20–63 years, 5M) and 20 healthy controls (HV, 21–59 years, 5 M). Results: In MO vs. HV, the overall FDG uptake was reduced in the left visual cortex, left medial frontal gyrus and bilaterally in the insula, somatosensory and motor cortices. Metabolisms of the posterior thalamus, brainstem including the periaqueductal gray (PAG), visual cortex, and (para)hippocampus, strongly increased with age in MO patients but not in HV. Disease duration positively correlated with PAG, (para)hippocampus and rostral anterior cingulate cortex (rACC) metabolisms in MO. Conclusion: Migraine patients, compared to HV, have a decreased resting metabolism in several areas belonging to the ‘‘pain/salience matrix’’, which is in line with previous neuroimaging studies. Metabolism of the rACC is specifically related to disease load whereas metabolism of other sensory processing regions is more affected by age. Whether these functional changes are due to repeated stereotyped attack-related stimulations and to a learning process with complexity reduction of neuronal connections and/or compensatory age-related hyperactivity, remains to be demonstrated [less ▲]

Detailed reference viewed: 27 (2 ULiège)
Full Text
Peer Reviewed
See detailA MACHINE-LEARNING CLASSIFIER FOR EPISODIC MIGRAINE BASED ON VISUAL EVOKED GAMMA BAND ACTIVITY
D'Ostilio, Kevin ULiege; Lisicki Martinez, Marco ULiege; SCHOENEN, Jean ULiege et al

in Cephalalgia (2016), 36(1S), 56

Introduction: Objective and reliable biomarkers of migraine may be of interest for diagnosis and research purposes. Neuroimaging-based machine-learning classifiers are promising but hampered by ... [more ▼]

Introduction: Objective and reliable biomarkers of migraine may be of interest for diagnosis and research purposes. Neuroimaging-based machine-learning classifiers are promising but hampered by availability and cost issues. Conversely, evoked potential are of easy access and affordable. They have provided increasing evidence that sensory information processing is impaired in migraine. We have used gamma band oscillations (GBOs) of visual evoked potentials (VEPs) to compute a machine-learning neural network classifier in episodic migraine. Materials and methods: We analyzed GBOs from VEPs (6x100 responses). Recordings were performed in two matched samples: a training sample composed of 43 migraine patients (EM) and 20 healthy volunteers (HV) and a validating sample of 18 EM and 10 HV. A logistic regression model of the training sample was performed to evaluate the relevance of the predictor variables. Ten neural networks were automatically generated based on late component frequency, n3-p4 and p4-n4 slopes, 1st block n1-p2 amplitude and age. Results: The logistic regression model of the training sample reached a significant classification rate of 79% (EM: 88%; HV: 60%, p¼0.002). The best neural network was able to classify the groups with an accuracy of 73% in the training phase and 89% in the subsequent validation (success rate HV: 90%; EM: 88%). The mean global accuracy within the training and validating samples were 69% (63–78%) and 84% (82–89%). Conclusions: This machine-learning neural network classifier based on visual GBOs provides an accurate and costefficient tool for objective migraine diagnosis. Further training and validation studies with new cohorts are warranted [less ▲]

Detailed reference viewed: 65 (3 ULiège)
Full Text
Peer Reviewed
See detailTRANSCUTANEOUS OCCIPITAL NERVE STIMULATION AND TRANSCRANIAL DIRECT CURRENT STIMULATION IN CHRONIC MIGRAINE: A PILOT COMPARISON OF THERAPEUTIC AND ELECTROPHYSIOLOGICAL EFFECTS
MAGIS, Delphine ULiege; D'Ostilio, Kevin ULiege; Baschi et al

in Cephalalgia (2016), 36(1S), 31

Background: Management of chronic migraine (CM) is often challenging. There is a need for more effective and better-tolerated preventive therapies. Among non-invasive neurostimulation procedures ... [more ▼]

Background: Management of chronic migraine (CM) is often challenging. There is a need for more effective and better-tolerated preventive therapies. Among non-invasive neurostimulation procedures, transcutaneous occipital nerve stimulation (tONS) would act via central pain modulation, while transcranial direct current stimulation (tDCS) would modify cortical excitability that is abnormal in CM. Objectives: In this pilot trial we compared the clinical effects of tDCS and tONS in refractory CM and their ability to modify nociception and cortical responsiveness. Methods: Forty-three CM patients (17 with history of drug overuse) applied either 2mA tDCS during 2 months (N¼20, cathode over visual cortex, anode over left DLPFC), or tONS during 3 months (N¼23, Cefaly Kit ArnoldTM), both in daily 20 min-sessions. Visual evoked potentials (VEP), nociceptive blink reflexes (nBR) and quantitative sensory testing were recorded before and after treatment. Results: During the last stimulation month, total headache days decreased in both groups ( 16.4% for tDCS, 17% for tONS, p<0.05). Migraine days were reduced by 21.4% (p¼0.06) and 22% (p<0.05) respectively, while 30% responder rates were 47% and 42%. Medication intake was significantly reduced after tONS ( 43%). There was no significant change of nBR in either group. VEP habituation reversed to an episodic migraine pattern, i.e. a deficit, after tONS but not after tDCS. Conclusion: tONS and inhibitory tDCS of the visual cortex are interesting non-invasive options for the treatment of CM, but these results have to be confirmed in a randomized controlled trial. tONS was able to induce recordable changes in visual cortex responsiveness [less ▲]

Detailed reference viewed: 120 (1 ULiège)
Full Text
Peer Reviewed
See detailHighlights in migraine electrophysiology: are controversies just reflecting disease heterogeneity?
MAGIS, Delphine ULiege; Lisicki Martinez, Marco ULiege; Coppola, Gianluca

in Current Opinion in Neurology (2016), 29(3)

PURPOSE OF REVIEW: In migraine, the brain is 'hyperresponsive', which refers to a deficit of habituation to repeated sensory stimuli between attacks. This deficit normalizes in peri-ictal and ictal phases ... [more ▼]

PURPOSE OF REVIEW: In migraine, the brain is 'hyperresponsive', which refers to a deficit of habituation to repeated sensory stimuli between attacks. This deficit normalizes in peri-ictal and ictal phases. A decreased cortical preactivation of thalamo-cortical origin and an impaired intracortical inhibition are probably involved in its pathophysiology. RECENT FINDINGS: The reality of a habituation deficit of visual evoked potentials, a neurophysiological 'hallmark' of interictal migraine, has been questioned. Blinding may be an issue, but some genetic, environmental, or behavioural differences could also exist between populations. A habituation deficit is found interictally in other sensory modalities, and strongly depends on the time of the recordings within the migraine cycle. An impaired thalamocortical drive is demonstrated in interictal phase, and normalizes in ictal phase as well as in chronic migraine, where a strength enhancement of primary cortical activation is observed. An interictal dysexcitability, of subcortical or primary cortical origin, is suggested by magnetic stimulation. These phenomena could occur in varying degrees depending on patients and on the migraine cycle, and account for the heterogeneity of electrophysiological results. SUMMARY: Finding a reliable electrophysiological biomarker for such a multifaceted and cycling disease as migraine is still a challenge. A better standardization of protocols would be worthwhile. [less ▲]

Detailed reference viewed: 32 (4 ULiège)