Distinct cerebral metabolic patterns related to high pain sensitivity in episodic or chronic migraine patients and healthy volunteers
D'Ostilio, Kevin ; Lisicki Martinez, Marco ; Schoenen, Jean 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 . 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 . Central sensitization is thought to be the culprit . 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: 11 (0 ULg)
Cerebral metabolism before and after external trigeminal nerve stimulation in episodic migraine
MAGIS, Delphine ; D'Ostilio, Kevin ; Thibaut, Aurore et al
in Cephalalgia : An International Journal of Headache (2016)Detailed reference viewed: 15 (2 ULg)
Anodal transcranial direct stimulation (tDCS) targeting the anterior cingulate gyrus for the preventive treatment of chronic cluster headache: a proof of concept trial.
MAGIS, Delphine ; D'Ostilio, Kevin ; 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: 33 (2 ULg)
Non-invasive vagus nerve stimulation with the gammaCore® in healthy subjects: is there electrophysiological evidence for activation of vagal afferents ?
Schoenen, Jean ; NONIS, Romain ; D'Ostilio, Kevin 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: 50 (1 ULg)
Noninvasive neurostimulation methods for migraine therapy: The available evidence
SCHOENEN, Jean ; ; MAGIS, Delphine et al
in Cephalalgia : An International Journal of Headache (2016)
Abstract Background: Migraine is one of the most disabling neurological disorders. The current pharmacological armamentarium is not satisfying for a large proportion of patients because the responder rate ... [more ▼]
Abstract Background: Migraine is one of the most disabling neurological disorders. The current pharmacological armamentarium is not satisfying for a large proportion of patients because the responder rate does not exceed 50% on average and the most effective drugs often induce intolerable side effects. During recent years, noninvasive central and peripheral neuromodulation methods have been explored for migraine treatment. Overview: A review of the available evidence suggests that noninvasive neuromodulation techniques could be beneficial for migraine patients. The transcranial stimulation methods allow modulating selectively cortical activity and can thus be curtailed to the patient’s pathophysiological profile, while transcutaneous stimulation of pericranial nerves likely modulates central pain control centers. Occipital single-pulse transcranial magnetic stimulation and transcutaneous supraorbital stimulation have the strongest evidence respectively for acute and preventive treatment. Transcranial direct current stimulation and repetitive magnetic stimulation are promising in pilot studies, but large sham-controlled trials are not yet available. Conclusions: The noninvasive neurostimulation methods are promising for migraine treatment and devoid of serious adverse effects allowing their combination with drug therapies. Their application in clinical practice will depend on the industry’s capacity to develop portable and user-friendly devices, and on the scientists’ capacity to prove their efficacy in randomized sham-controlled trials. [less ▲]Detailed reference viewed: 16 (1 ULg)
Invasive occipital nerve stimulation for refractory chronic cluster headache: what evolution at long-term? Strengths and weaknesses of the method.
MAGIS, Delphine ; ; Schoenen, Jean
in Journal of Headache & Pain (2016)
BACKGROUND: Invasive Occipital Nerve Stimulation (iONS) is a costly technique which appears effective in drug-refractory chronic cluster headache (drCCH) management. Available data on long-term ... [more ▼]
BACKGROUND: Invasive Occipital Nerve Stimulation (iONS) is a costly technique which appears effective in drug-refractory chronic cluster headache (drCCH) management. Available data on long-term effectiveness and safety of iONS in this indication are scarce, though they could be useful to neurologists and patients in daily practice. The purpose of this short report is to discuss the very long-term outcome of a drCCH cohort, including adverse events. FINDINGS: Previously, favourable results were obtained with iONS in 15 drCCH patients: 80 % were significantly improved and 60 % were pain free. We report here the very long-term follow-up (up to nine years) of 10 patients belonging to this cohort. Meanwhile 5 patients had to be definitively explanted because of device infection (3) or paresthesia intolerance (2). Four patients (40 %) evolved to an episodic form of CH. Six remained chronic but their attack frequency was decreased by 70 % on average. Intake of preventive drugs is still necessary in 80 % of patients. All patients needed at least one battery replacement. CONCLUSIONS: Up to nine years after implantation, iONS is still effective in most patients with drCCH. Concomitant preventive drugs remain often necessary. Forty percent of patients reverse to episodic CH, possibly by natural history. iONS is not a benign procedure but device-related complications appear similar to those reported with other invasive neurostimulators. [less ▲]Detailed reference viewed: 11 (2 ULg)
Highlights in migraine electrophysiology: are controversies just reflecting disease heterogeneity?
MAGIS, Delphine ; Lisicki Martinez, Marco ;
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: 16 (4 ULg)
Transcranial direct current stimulation and transcutaneous occipital nerve stimulation in chronic migraine: a pilot-comparison of therapeutic and electrophysiological effects.
Schoenen, Jean ; D'Ostilio, Kevin ; et al
Poster (2016)Detailed reference viewed: 25 (1 ULg)
Non-invasive vagus nerve stimulation for PREVention and Acute treatment of chronic cluster headache (PREVA): A randomised controlled study.
; ; et al
in Cephalalgia : An International Journal of Headache (2015)
Background: Chronic cluster headache (CH) is a debilitating disorder for which few well-controlled studies demonstrate effectiveness of available therapies. Non-invasive vagus nerve stimulation (nVNS) was ... [more ▼]
Background: Chronic cluster headache (CH) is a debilitating disorder for which few well-controlled studies demonstrate effectiveness of available therapies. Non-invasive vagus nerve stimulation (nVNS) was examined as adjunctive prophylactic treatment of chronic CH. Methods: PREVA was a prospective, open-label, randomised study that compared adjunctive prophylactic nVNS (n=48) with standard of care (SoC) alone (control (n=49)). A two-week baseline phase was followed by a four-week randomised phase (SoC plus nVNS vs control) and a four-week extension phase (SoC plus nVNS). The primary end point was the reduction in the mean number of CH attacks per week. Response rate, abortive medication use and safety tolerability were also assessed. Results: During the randomised phase, individuals in the intent-to-treat population treated with SoC plus nVNS (n=45) had a significantly greater reduction in the number of attacks per week vs controls (n=48) (-5.9 vs -2.1, respectively) for a mean therapeutic gain of 3.9 fewer attacks per week (95% CI: 0.5, 7.2; p=0.02). Higher #50% response rates were also observed with SoC plus nVNS (40% (18/45)) vs controls (8.3% (4/48); p<0.001). No serious treatment-related adverse events occurred. Conclusion: Adjunctive prophylactic nVNS is a well-tolerated novel treatment for chronic CH, offering clinical benefits beyond those with SoC. [less ▲]Detailed reference viewed: 22 (7 ULg)
Cerebral FDG uptake changes with supraorbital transcutaneous electrical stimulation for episodic migraine prevention
D'Ostilio, Kevin ; Thibaut, Aurore ; Laureys, Steven et al
Conference (2015, May)
Background: A recent multicentre RCT has shown that supraorbital transcutaneous stimulation (STS) targeting branches of the ophtalmic nerve with the Cefaly® device is effective as a preventive therapy for ... [more ▼]
Background: A recent multicentre RCT has shown that supraorbital transcutaneous stimulation (STS) targeting branches of the ophtalmic nerve with the Cefaly® device is effective as a preventive therapy for migraine (Schoenen et al., Neurology 2013). However, the mechanisms of action in the central nervous system remain unknown. Here, we conducted voxel-based analyses of FDG-PET to evaluate metabolic changes immediately after the first STS session and after 3 months of treatment in patients with migraine. Methods: Twenty-eight subjects participated in the experiment: 14 patients with episodic migraine (ICHD3 beta criteria) and 14 age-matched controls. Healthy volunteers underwent only one FDG-PET scan whereas patients were scanned at baseline, directly after a first session of STS and after 3 months of daily treatment. Results: Compliant patients showed a significant decrease in the number of attacks (p = 0.03). When compared to controls, patients (n = 14) at baseline were hypometabolic in the fronto-temporal regions (p < 0.001), especially in the orbitofrontal (OFC) and perigenual anterior cingulate cortex. OFC hypometabolism was not correlated with medication intake. In compliant patients, daily STS for 3 months was followed by a normalization of the fronto-temporal hypometabolism (p< 0.001; OFC: pFWE<0.01). Conclusion: Our study suggests that the OFC is hypoactive in episodic migraine. STS with the Cefaly° device is able to normalize this hypoactivity. This indicates that STS exerts its beneficial effect via slow neuromodulatory mechanisms, as also previously shown for percutaneous occipital nerve stimulation in refractory cluster headache (Magis et al., BMC Neurology 2011). [less ▲]Detailed reference viewed: 144 (5 ULg)
Targeting pericranial nerve branches to treat migraine: Current approaches and perspectives.
; ; MAGIS, Delphine et al
in Cephalalgia : An International Journal of Headache (2015)Detailed reference viewed: 30 (5 ULg)
Diagnosis, pathophysiology and management of chronic migraine: a proposal of the Belgian Headache Society.
; ; MAGIS, Delphine et al
in Acta Neurologica Belgica (2015), 35(5), 437-442
This is a review of the pathophysiology of chronic migraine and of available therapies with a proposal for an algorithm of management.Detailed reference viewed: 32 (0 ULg)
Neuromodulation in migraine: state of the art and perspectives.
in Expert review of medical devices (2015)
Migraine is a highly prevalent and disabling disease. The drugs prescribed for migraine prophylaxis can have intolerable side effects or can be ineffective. Neuromodulation techniques are increasingly ... [more ▼]
Migraine is a highly prevalent and disabling disease. The drugs prescribed for migraine prophylaxis can have intolerable side effects or can be ineffective. Neuromodulation techniques are increasingly used in neurology. Transcutaneous supraorbital nerve stimulation is effective in episodic migraine prevention, whereas vagus nerve stimulation provides interesting results in acute migraine therapy. Transcranial stimulation techniques gave variable, and sometimes contradictory, results. The visual cortex is the target of choice in migraine: studies in migraine prevention and aura acute treatment are encouraging. These noninvasive therapies appear safe with a low rate of side effects. Available studies of invasive occipital nerve stimulation in chronic migraine gave modest results; but invasive occipital nerve stimulation offers a new hope to highly disabled patients who failed to respond to any other treatment. In the future, neuromodulation will probably take an increasing place in migraine treatment, as add-on therapy or alternative to medications, especially because of its attractive safety profile. [less ▲]Detailed reference viewed: 30 (1 ULg)
Neuromodulation in cluster headache.
; ; MAGIS, Delphine et al
in Advances and technical standards in neurosurgery (2015), 42
Medically refractory chronic cluster headache (CH) is a severely disabling headache condition for which several surgical procedures have been proposed as a prophylactic treatment. None of them have been ... [more ▼]
Medically refractory chronic cluster headache (CH) is a severely disabling headache condition for which several surgical procedures have been proposed as a prophylactic treatment. None of them have been evaluated in controlled conditions, only open studies and case series being available. Destructive procedures (radiofrequency lesioning, radiosurgery, section) and microvascular decompression of the trigeminal nerve or the sphenopalatine ganglion (SPG) have induced short-term improvement which did not maintain on long term in most of the patients. They carried a high risk of complications, including severe sensory loss and neuropathic pain, and consequently should not be proposed in first intention.Deep brain stimulation (DBS), targeting the presumed CH generator in the retro-hypothalamic region or fibers connecting it, decreased the attack frequency >50 in 60 % of the 52 patients reported. Complications were infrequent: gaze disturbances, autonomic disturbances, and intracranial hemorrhage (2).Occipital nerve stimulation (ONS) was efficient (decrease of attack frequency >50 %) in about 70 % of the 60 patients reported, with a low risk of complications (essentially hardware related). Considering their respective risks, ONS should be proposed first and DBS only in case of ONS failure.New on-demand chronically implanted SPG stimulation seemed to be efficient to abort CH attacks in a pilot controlled trial, but its long-term safety needs to be further studied. [less ▲]Detailed reference viewed: 21 (2 ULg)
Refractory chronic migraine: a consensus statement on clinical definition from the European Headache Federation.
; ; et al
in The journal of headache and pain (2014), 15
The debate on the clinical definition of refractory Chronic Migraine (rCM) is still far to be concluded. The importance to create a clinical framing of these rCM patients resides in the complete ... [more ▼]
The debate on the clinical definition of refractory Chronic Migraine (rCM) is still far to be concluded. The importance to create a clinical framing of these rCM patients resides in the complete disability they show, in the high risk of serious adverse events from acute and preventative drugs and in the uncontrolled application of therapeutic techniques not yet validated.The European Headache Federation Expert Group on rCM presents hereby the updated definition criteria for this harmful subset of headache disorders. This attempt wants to be the first impulse towards the correct identification of these patients, the correct application of innovative therapeutic techniques and lastly aim to be acknowledged as clinical entity in the next definitive version of the International Classification of Headache Disorders 3 (ICHD-3 beta). [less ▲]
Diagnosis, pathophysiology and management of chronic migraine: a proposal of the Belgian Headache Society.
; ; MAGIS, Delphine et al
in Acta neurologica Belgica (2014)
Chronic migraine (CM) is a disabling neurological condition affecting 0.5-2 % of the population. In the current third edition of the International Classification of Headache Disorders, medication overuse ... [more ▼]
Chronic migraine (CM) is a disabling neurological condition affecting 0.5-2 % of the population. In the current third edition of the International Classification of Headache Disorders, medication overuse is no longer an exclusion criterion and CM is diagnosed in patients suffering from at least 15 headache days per month of which at least eight are related to migraine. CM is difficult to treat, and preventive treatment options are limited. We provide a pathogenetic model for CM, integrating the latest findings from neurophysiological and neuroimaging studies. On behalf of the Belgian Headache Society, we present a management algorithm for CM based on the international literature and adapted to the Belgian situation. Pharmacological treatment options are discussed, and recent data on transcranial and invasive neuromodulation studies in CM are reviewed. An integrated multimodal treatment programme may be beneficial to refractory patients, but at present, this approach is only supported by a limited number of observational studies and quite variable between centres. [less ▲]Detailed reference viewed: 32 (1 ULg)
Effects of visual cortex activation on the nociceptive blink reflex in healthy subjects.
; ; MAGIS, Delphine et al
in PloS one (2014), 9(6), 100198
Bright light can cause excessive visual discomfort, referred to as photophobia. The precise mechanisms linking luminance to the trigeminal nociceptive system supposed to mediate this discomfort are not ... [more ▼]
Bright light can cause excessive visual discomfort, referred to as photophobia. The precise mechanisms linking luminance to the trigeminal nociceptive system supposed to mediate this discomfort are not known. To address this issue in healthy human subjects we modulated differentially visual cortex activity by repetitive transcranial magnetic stimulation (rTMS) or flash light stimulation, and studied the effect on supraorbital pain thresholds and the nociceptive-specific blink reflex (nBR). Low frequency rTMS that inhibits the underlying cortex, significantly decreased pain thresholds, increased the 1st nBR block ipsi- and contralaterally and potentiated habituation contralaterally. After high frequency or sham rTMS over the visual cortex, and rMS over the right greater occipital nerve we found no significant change. By contrast, excitatory flash light stimulation increased pain thresholds, decreased the 1st nBR block of ipsi- and contralaterally and increased habituation contralaterally. Our data demonstrate in healthy subjects a functional relation between the visual cortex and the trigeminal nociceptive system, as assessed by the nociceptive blink reflex. The results argue in favour of a top-down inhibitory pathway from the visual areas to trigemino-cervical nociceptors. We postulate that in normal conditions this visuo-trigeminal inhibitory pathway may avoid disturbance of vision by too frequent blinking and that hypoactivity of the visual cortex for pathological reasons may promote headache and photophobia. [less ▲]Detailed reference viewed: 32 (2 ULg)
Analysis and clinical correlates of 20 Hz photic driving on routine EEG in migraine.
; Gérard, Paul ; et al
in Acta neurologica Belgica (2014)
Enhanced photic driving (PD) during high-frequency flicker stimulation, the so-called H response, is a classical feature of migraine patients between attacks, but is thought to be of poor clinical utility ... [more ▼]
Enhanced photic driving (PD) during high-frequency flicker stimulation, the so-called H response, is a classical feature of migraine patients between attacks, but is thought to be of poor clinical utility. Visual inspection of the EEG for its detection may not be reliable, however, data on its possible correlations with clinical features and migraine pathophysiology are scarce. We have compared visual inspection and EEG spectral analysis to detect abnormal PD in 280 consecutive migraine patients of our headache clinic (episodic migraine without aura, n = 171; chronic migraine, n = 48; migraine with aura, n = 61) and in a group of 24 non-migrainous neurological controls. Spectral frequency analyses were performed blindly by one of us (YF). On visual inspection, 50.4 % of migraineurs were thought to have increased 20 Hz PD. After spectral analysis, only 62.4 % of them had PD power superior to the mean + 95 % CI of the control group. Sensitivity of visually identified PD was 82.24 %, specificity 69.36 %. Increased PD on spectral analysis was more prevalent in episodic migraine than in chronic migraine, in patients with low attack frequency, in those with ictal autonomic symptoms in addition to nausea and in those with a strong family history of migraine. We confirm therefore that 20 Hz photic driving is of little diagnostic utility and its prevalence in migraine overestimated on visual inspection. Its presence on spectral analysis of the EEG, however, might be of pathophysiological interest, as it identifies subgroups of migraineurs of whom the common denominator could be lack of habituation of cortical responses during repetitive stimulation. [less ▲]Detailed reference viewed: 16 (0 ULg)
Neurostimulation for Headaches: Where Are We? Where Are We Going?
in May, Arne; Baron, Ralf (Eds.) Headache and Pain (2014)Detailed reference viewed: 16 (0 ULg)
Variabilité du spectre clinique des céphalées trigéminales autonomes: 2 cas illustratifs
in Revue Neurologique (2014), 170Detailed reference viewed: 33 (4 ULg)