Effectiveness and tolerability of eptinezumab in treating patients with migraine resistant to conventional preventive medications and CGRP (receptor) antibodies: a multicentre retrospective real-world analysis from Germany.

BACKGROUND: Eptinezumab is a monoclonal antibody that targets calcitonin gene-related peptide (CGRP mAb) and is used for migraine prophylaxis. Efficacy data are mainly from clinical trials, real-world data are hardly available yet. Reimbursement policy in Germany leads to eptinezumab mainly being used in patients having failed pre-treatment with other CGRP mAb. To date, it is unclear whether eptinezumab is efficacious and well tolerated in this population and how the treatment response differs from patients who are naive to CGRP mAbs. METHODS: We analysed clinical routine data of 79 patients (episodic migraine (EM): n = 19; chronic migraine (CM): n = 60) from four different centres in Germany. All patients were treated with eptinezumab (100mg). Differences in monthly headache (MHD), migraine (MMD) and acute medication days (AMD) after three months were analysed. The correlation of response with the number of CGRP mAb failures was evaluated. Significance level has been corrected (alpha = 0.017). RESULTS: After three months MHD, MMD and AMD were significantly reduced. In EM, the median reduction for MHD was 4.0 days (IQR: -6.5 to -1.0; p = 0.001), for MMD 3.0 days (IQR: -5.5 to -1.5; p < 0.001) and for AMD 2.0 days (IQR: -5.0 to -0.5; p = 0.006). In CM, median reduction of MHD was 4 days (IQR: -8.0 to 0.0; p < 0.001), 3.0 days (IQR: -6.0 to-1.0; p < 0.001) for MMD and 1.0 day (IQR: -5.0 to 0.0; p < 0.001) for AMD. All patients were resistant to conventional preventive therapies and most to CGRP mAbs. Fourteen patients had never received a CGRP mAb and 65 patients had received at least one mAb without sufficient effectiveness and/or intolerability (one: n = 20, two: n = 28, three: n = 17). There was a significant association between the number of prior therapies and the 30% MHD responder rate (none: 78.6%, one: 45.0%, two: 32.1%, three: 23.5%, p = 0.010). Regarding tolerability, 10.4% (8/77) reported mild side effects. CONCLUSIONS: The effectiveness of eptinezumab is significantly reduced in patients who have not previously responded to other CGRP mAbs. However, limitations such as the retrospective nature of the analysis, the small sample size and the short treatment period with only the lower dose of eptinezumab must be considered when interpreting the results.

Cognitive deficits in patients with peripheral vestibular dysfunction.

BACKGROUND AND PURPOSE: Previous studies demonstrated cognitive deficits in patients with peripheral vestibulopathy (PVP) with dysfunction of spatial navigation and orientation, but also documented cognitive decline in nonspatial abilities. This study evaluates cognitive deficits in patients with unilateral vestibulopathy (UVP) as well as bilateral vestibulopathy (BVP) in multiple cognitive domains using common screening tests to reliably detect these deficits in clinical practice. METHODS: This prospective study compared patients with UVP and BVP to age- and sex-matched healthy controls (HC). Tests included the Alzheimer's Disease Assessment Scale (ADAS), Mini-Mental Status Examination (MMSE), Trail Making Test Part A and B, Clock Drawing Task, Executive Interview-25 (EXIT25), Dementia Detection (DemTect), and the Judgment of Line Orientation (JLO). The Montgomery-Åsberg Depression Rating Scale was used to control for depression. Videonystagmography objectively reconfirmed PVP. The Vertigo Symptoms Scale and the Dizziness Handicap Inventory were used to assess for symptom severity and restrictions of activities of daily living. RESULTS: Eighty-one patients (65 UVP, 16 BVP) were compared to 55 HC. Patients showed impairment in ADAS, MMSE, DemTect, EXIT25, and JLO. No differences between UVP and BVP were detected. The relative risk (RR) estimates of developing cognitive deficits following PVP were increased. The RR for the ADAS was higher in BVP (RR = 4.91, 95% confidence interval [CI] = 1.87-12.9, p = 0.001) than in UVP (RR = 3.75, 95% CI = 1.65-8.51, p = 0.002), but was similar for the MMSE and DemTect between groups. CONCLUSIONS: Patients with PVP showed deficits in multiple cognitive domains including nonspatial cognitive abilities. Vestibulopathy could be a risk factor for the development of cognitive impairment.

No structural brain alterations in new daily persistent headache - a cross sectional VBM/SBM study.

OBJECTIVE: To identify grey matter alterations in patients suffering new daily persistent headache to enrich the pathophysiological concept of this rare headache disorder characterised by a distinct, clearly remembered onset and its instant chronification. METHOD: Magnetic resonance-based voxel-based and surface-based morphometry was used to investigate 23 patients suffering from new daily persistent headache and 23 age- and gender-matched healthy controls with 1.5 Tesla MRI.Independent statistical analysis was performed at three sites using statistical parametric mapping, as well as FSL(FMRIB Software Library)-based approaches. RESULTS: No grey matter changes were detected using this sophisticated and cross-checked method. CONCLUSION: The absence of structural brain changes in patients with new daily persistent headache contribute to the recent discussion regarding structural alterations in primary headache disorders in general and does not provide evidence for grey matter changes being associated with the pathophysiology of new daily persistent headache. Future research will have to determine the underlying pathophysiological mechanisms of this disorder.

Prevalence and risk factors of migraine and non-migraine headache in older people - results of the Heinz Nixdorf Recall study.

BACKGROUND: The prevalence of migraine and non-migraine headache declines with age. METHODS: Data from the third visit (2011-2015) of the population-based Heinz Nixdorf Recall study were analysed (n = 2038, 51% women, 65-86 years). Possible risk factors for headache activity (obesity, education, smoking, sports, alcohol, partnership status, living alone, having children, sleep quality, depression, hypertension, diabetes mellitus, stroke, coronary heart disease, medication), and headache symptoms were assessed. We estimated the lifetime prevalence and the prevalence of current active headache of migraine with and without aura, and non-migraine headache. The associations between possible risk factors and headache activity (active vs. inactive) were estimated by age and sex-adjusted odds ratios and 95% confidence intervals (OR [95% CI]) using multiple logistic regression. RESULTS: The lifetime prevalence of migraine was 28.6% (n = 584). One hundred and ninety-two (9.4%) had still-active migraine, 168 (3.5%) had migraine with aura, and 416 (5.9%) had migraine without aura. One hundred and sixty-eight (8.2%) had "episodic infrequent migraine, 0-8 headache days/month", 10 (0.5%) had "episodic frequent migraine, 9-14 headache days/month", and five (0.2%) had "chronic migraine, ≥15 headache days/month". Overall, 10 (0.5%) had "chronic headache, any headache on ≥15 days/month". Female gender and younger age were the most important associated migraine risk factors. Depression (1.62 [1.06; 2.47]) and poor sleep (1.06 [1.00; 1.12]) were associated with migraine and headache activity in general. Antihypertensives were associated with headache remission (0.80 [0.64; 1.00]). Additionally, undertaking less sports (0.72 [0.51; 1.03]) was associated with higher migraine activity. CONCLUSIONS: Headaches and migraines are not rare in the older population. They are related to mood and sleep disturbance, and migraine even to less physical activity. Antihypertensives are related to headache remission.

Sensitized rotatory motion perception and increased susceptibility to motion sickness in vestibular migraine: A cross-sectional study.

BACKGROUND AND PURPOSE: Vestibular migraine (VM) patients are ictally and interictally hypersensitive for self-motion and visual perception. Increased cortical excitability of the vestibular system represented by lowered motion perception thresholds might play an important role in the pathophysiology of VM. We aimed to compare motion perception thresholds and the vegetative response to rotatory motion, as well as the vestibulo-ocular reflex (VOR) during rotation in VM patients compared to healthy controls (HC). METHODS: In this cross-sectional study, 28 female VM patients in the interictal state and 33 age- and gender-matched HC were investigated sitting in a motorized rotary chair shielded regarding visual and acoustic stimuli for 20 min with slowly increasing velocity (maximum = 72°/s). The motion perception threshold was indicated by the participants by pushing a button. During and after rotation, participants rated the presence and extent of motion sickness using a sickness rating scale. RESULTS: We detected lower motion perception thresholds (7.54°/s vs. 23.49°/s; p < 0.001) in VM patients compared to HC but no difference at the basic VOR thresholds. Furthermore, the patients showed enhanced susceptibility to motion sickness during and after the rotation. CONCLUSIONS: We provide evidence for decreased motion perception thresholds and pronounced susceptibility to motion sickness in VM patients in the interictal state, which could indicate alterations in higher levels of vestibular processing. Future studies should determine whether this could be the pathophysiological hallmark of VM either as a unique disease entity or in differentiation from other forms of migraine.

Reduced vestibular perception thresholds in persistent postural-perceptual dizziness- a cross-sectional study.

BACKGROUND: Persistent postural-perceptual dizziness (PPPD) is the most common functional vestibular disorder. A multisensory mismatch altered by psychological influences is considered to be an important pathophysiological mechanism. Increased cortical and subcortical excitability may play a role in the pathophysiology of PPPD. We hypothesized that decreased motion perception thresholds reflect one mechanism of the abnormal vestibular responsiveness in this disorder. We investigated the vestibular perception thresholds and the vestibular ocular reflex with a rotatory chair experiment to gain insights in the processing and adaption to vestibular provocation. METHODS: In this cross-sectional study 26 female PPPD patients and 33 healthy female age matched controls (HC) were investigated sitting in a motorized rotary chair shielded regarding visual and acoustic stimuli. The chair was rotated for 20 minutes with slowly increasing velocity to a maximum of 72°/s. We functionally tested motion perception thresholds and vegetative responses to rotation as well as vestibular-ocular reflex thresholds. We additionally investigated several psychological comorbidities (i.e. depression, anxiety, somatosensory amplification) using validated scores. Conventional dizziness scores were obtained to quantify the experienced dizziness and impact on daily life. RESULTS: PPPD patients showed a significant reduced vestibulo-perceptual threshold (PPPD: 10.9°/s vs. HC: 29.5°/s; p<0.001) with increased motion sensitivity and concomitant vegetative response during and after the chair rotation compared to healthy controls. The extent of increased vestibular sensitivity was in correlation with the duration of the disease (p=0.043). No significant difference was measured regarding nystagmus parameters between both groups. CONCLUSION: PPPD patients showed increased vegetative response as well as decreased vestibulo-perceptual thresholds which are related to disease duration. This is of interest as PPPD might be sustained by increased vestibular excitability leading to motion intolerance and induction of dizziness when exposed to movement.

Preventive treatment with CGRP monoclonal antibodies restores brain stem habituation deficits and excitability to painful stimuli in migraine: results from a prospective case-control study.

BACKGROUND & OBJECTIVES: Calcitonin gene-related peptide ligand/receptor (CGRP) antibodies effectively reduce headache frequency in migraine. It is understood that they act peripherally, which raises the question whether treatment merely interferes with the last stage of headache generation or, alternatively, causes secondary adaptations in the central nervous system and might thus possess disease modifying potential. This study addresses this question by investigating the nociceptive blink reflex (nBR), which is closely tied to central disease activity, before and after treatment with CGRP antibodies. METHODS: We enrolled 22 patients suffering episodic migraine (21 female, 46.2 ± 13.8 years of age) and 22 age-/gender-matched controls. Patients received assessments of the nBR (R2 component, 10 trials, 6 stimuli/trial) before (V0) and three months (V3) after treatment with CGRP antibodies started, controls were assessed once. The R2 area (R2a) and habituation (R2h; gradient of R2a against stimulus order) of the stimulated/non-stimulated side (_s/_ns) following repeated supraorbital stimulation provide a direct readout of brainstem excitability and habituation as key mechanisms in migraine. RESULTS: All patients showed a substantial reduction of headache days/month (V0: 12.4±3.3, V3: 6.6 ± 4.9). R2a_s (Fglobal=5.86, p<0.001; block 1: R2a_s: -28%, p<0.001) and R2a_ns (Fglobal=8.22, p<0.001, block 1: R2a_ns: -22%, p=0.003) were significantly decreased, and R2h_ns was significantly enhanced (Fglobal=3.07, p<0.001; block 6: R2h_ns: r=-1.36, p=0.007) from V0 to V3. The global test for changes of R2h_s was non-significant (Fglobal=1.46, p=0.095). Changes of R2h significantly correlated with improvement of headache frequency (R2h_s, r=0.56, p=0.010; R2h_ns: r=0.45, p=0.045). None of the nBR parameters assessed at baseline predicted treatment response. DISCUSSION: We provide evidence that three months of treatment with CGRP antibodies restores brain stem responses to painful stimuli and thus might be considered disease modifying. The nociceptive blink reflex may provide a biomarker to monitor central disease activity. Future studies should evaluate the blink reflex as a clinical biomarker to predict treatment response at baseline and to establish the risk of relapse after treatment discontinuation. TRIAL REGISTRATION: This trial was prospectively registered at clinicaltrials.gov (ID: NCT04019496, date of registration: July 15, 2019).

Efficacy and safety of fremanezumab in clinical trial participants aged ≥60 years with episodic or chronic migraine: pooled results from 3 randomized, double-blind, placebo-controlled phase 3 studies.

BACKGROUND: Although migraine is less common in older people, preventive treatment of migraine in these individuals may be more challenging due to the presence of multiple comorbidities and polypharmacy. Additionally, evidence for migraine treatment efficacy, safety, and tolerability is limited in this population. We evaluated efficacy, safety, and tolerability of fremanezumab, a fully humanized monoclonal antibody (IgG2Δa) that selectively targets calcitonin gene-related peptide (CGRP), in clinical trial participants aged ≥60 years with episodic migraine (EM) or chronic migraine (CM). METHODS: This analysis included data from 3 randomized, double-blind, placebo-controlled phase 3 studies: the HALO EM study, HALO CM study, and FOCUS study in participants with EM or CM and prior inadequate response to 2-4 migraine preventive medication classes. Participants in all studies were randomized 1:1:1 to receive 12 weeks of subcutaneous treatment with quarterly fremanezumab (Months 1/2/3: EM/CM, 675 mg/placebo/placebo), monthly fremanezumab (Months 1/2/3: EM, 225 mg/225 mg/225 mg; CM, 675 mg/225 mg/225 mg), or matched monthly placebo. RESULTS: These pooled analyses included 246 participants aged ≥60 years. Reductions in monthly migraine days from baseline over 12 weeks were significantly greater with fremanezumab (least-squares mean change from baseline [standard error]: quarterly fremanezumab, - 4.3 [0.59]; monthly fremanezumab, - 4.6 [0.54]) versus placebo (placebo, - 2.3 [0.57]; both P < 0.01 vs placebo). As early as Week 1, significant reductions from baseline in weekly migraine days were observed with fremanezumab versus placebo (both P < 0.01). With fremanezumab treatment versus placebo, a significantly higher proportion of participants achieved ≥50% reduction in monthly migraine days, and significant improvements in disability and quality-of-life outcomes were observed (P < 0.05). Proportions of participants experiencing serious adverse events and adverse events leading to discontinuation were low and similar in the fremanezumab and placebo groups. Efficacy and safety results were comparable to the overall pooled population (N = 2843). CONCLUSIONS: This pooled subgroup analysis demonstrates that fremanezumab treatment is efficacious and well-tolerated over 12 weeks in participants aged ≥60 years with EM or CM. These data may help healthcare providers with clinical decision making and preventive treatment selection for older patients with migraine. TRIAL REGISTRATION: ClinicalTrials.gov identifiers: HALO CM: NCT02621931 ; HALO EM: NCT02629861 ; FOCUS: NCT03308968 .

Erenumab in highly therapy-refractory migraine patients: First German real-world evidence.

BACKGROUND: Calcitonin gene related peptide (CGRP) monoclonal antibodies (mAB) are the first specific migraine prophylactic medication. Erenumab is the only CGRP mAB targeting the CGRP receptor. Clinical data regarding efficacy and tolerability of erenumab in highly therapy-refractory patients are not available, yet, although many patients treated with CGRP mAB under real world conditions can be considered as highly therapy-refractory. METHODS: Clinical routine data of highly therapy-refractory migraine patients treated with erenumab 70 mg for 3 months between November 2018 and December 2019 in the West German Headache Center, University Hospital Essen, Germany, were analysed. Monthly migraine days (MMD), monthly headache days (MHD) and days of acute medication intake (AMD) were assessed. Statistical analysis was performed using the Wilcoxon test. Descriptive statistics were performed to evaluate changes of vegetative symptoms, acute medication response, side effects, as well as treatment satisfaction. RESULTS: Complete clinical data were available for 26 episodic (EM) and 74 chronic (CM) migraineurs. Sixty-six % (n = 49) of CM patients had an additional medication overuse headache (MOH). After 3 months 57.7% of EM patients and 41.9% of CM patients had a 50% or greater reduction of MMD. The mean number of MMD was reduced by 3.43 (SE 1.26) in EM, and by 4.72 (SE 0.87) in CM. Thirty-nine patients (52.7%) returned from chronic to episodic course of migraine. After 3 months, 23 patients (46.9%) were not suffering from a MOH anymore. CONCLUSIONS: Erenumab seems to be a promising therapeutic option in highly therapy-refractory migraine patients. TRIAL REGISTRATION: Retrospective registered.

Polarity-specific modulation of pain processing by transcranial direct current stimulation - a blinded longitudinal fMRI study.

BACKGROUND: To enrich the hitherto insufficient understanding regarding the mechanisms of action of transcranial direct current stimulation (tDCS) in pain disorders, we investigated its modulating effects on cerebral pain processing using functional magnetic resonance imaging (fMRI). METHODS: Thirteen right-handed healthy participants received 20 min of 1.5 mA tDCS applied over the primary motor cortex thrice and under three different stimulation pattern (1.anodal-tDCS, 2.cathodal-tDCS, and 3.sham-tDCS) in a blinded cross-over design. After tDCS neural response to electric trigeminal-nociceptive stimulation was investigated using a block designed fMRI. RESULTS: Pain stimulation showed a distinct activation pattern within well-established brain regions associated with pain processing. Following anodal tDCS increased activation was detected in the thalamus, basal ganglia, amygdala, cingulate, precentral, postcentral, and dorsolateral prefrontal cortex, while cathodal t-DCS showed decreased response in these areas (pFWE < 0.05). Interestingly the observed effect was reversed in both control conditions (visual- and motor-stimulation). Behavioral data remained unchanged irrespective of the tDCS stimulation mode. CONCLUSIONS: This study demonstrates polarity-specific modulation of cerebral pain processing, in reconfirmation of previous electrophysiological data. Anodal tDCS leads to an activation of the central pain-network while cathodal tDCS does not. Results contribute to a network-based understanding of tDCS's impact on cerebral pain-processing.

No Pattern Alteration in Single Nocturnal Melatonin Secretion in Patients With Hypnic Headache: A Case-Control Study.

OBJECTIVE: To investigate headache-related serum melatonin levels and melatonin excretion rhythmicity in patients with hypnic headache (HH). BACKGROUND: Strict sleep dependency of headache attacks is a pathognomonic feature of HH. Changes in melatonin levels, a marker for circadian rhythm, are assumed to play a pivotal role in the pathophysiology of HH. METHODS: Serum melatonin levels were acquired in nine patients with HH and nine age- and gender-matched healthy controls over a 20-hour time period (12 pm, 4 pm, 7 pm, 10 pm, time of headache, and 8 am). RESULTS: No significant changes of melatonin levels could be detected comparing HH patients and healthy controls. Melatonin excretion rhythmicity was not significantly altered in patients with HH (Mean melatonin level in ng/mL ± SD, patients vs controls at 12 pm: 21.5 ± 9.5 vs 13.6 ± 6.3 [P = .077], 4 pm: 18.4 ± 8.4 vs 14.0 ± 4.7 [P = .222], 7 pm: 19.4 ± 5.1 vs 15.1 ± 4.5 [P = .094], 10 pm: 59.5 ± 45.0 vs 29.4 ± 12.7 [P =.136], headache time: 96.9 ± 68.3 vs 49.1 ± 22.8 [P = .94], and 8 am: 31.6 ± 18.3 vs 26.7 ± 15.6 [P = .489]). CONCLUSION: This study is not able to confirm a significant role of melatonin concentration changes in the pathophysiology of HH and vetoes that melatonin deficiency plays a major role in the pathophysiology of the disorder.

Short Latency Gray Matter Changes in Voxel-Based Morphometry following High Frequent Visual Stimulation.

Magnetic resonance imaging studies using voxel-based morphometry (VBM) detected structural changes in the human brain within periods of months or weeks. The underlying molecular mechanisms of VBM findings remain unresolved. We showed that simple visual stimulation by an alternating checkerboard leads to instant, short-lasting alterations of the primary and secondary visual cortex detected by VBM. The rapidness of occurrence (i.e., within 10 minutes) rather excludes most of the proposed physiological mechanism such as neural or glial cell genesis/degeneration or synapse turnover. We therefore favour cerebral fluid shifts to be the underlying correlate of the here observed VBM gray matter changes. Fast onset gray matter changes might be one important explanation for the inconsistency of VBM study results that often raise concern in regard to the validity of presented data. This study shows that changes detectable by VBM may occur within a few minutes after physiological stimulation and must be considered in future VBM experiments to avoid misinterpretation of results.

Vestibular migraine.

BACKGROUND: The combination of vertigo, dizziness and balance disturbance with migraine is called vestibular migraine. Although it is estimated that up to 1% of the population suffers from this disease, it is still widely unknown and often underdiagnosed. Recently, the International Headache Society and the Báràny Society published the first joint document with mutually accepted diagnostic criteria for vestibular migraine. METHOD: This review summarizes current knowledge on vestibular migraine with regard to epidemiology, clinical presentation, pathophysiology, differential diagnosis and therapeutic options. RESULTS: Approximately 30-50% of patients with migraine report vertigo, dizziness or balance disturbances with at least one migraine attack. Vestibular migraine often appears in a temporal delay to the first onset of migraine headache. In some patients the symptom of sudden onset disequilibrium was the main complaint and more worrisome than the accompanying migraine headache. The duration of attacks varies from a few seconds up to few days. The underlying pathophysiology of vestibular migraine is still widely unknown. As an important differential diagnosis, Ménière's disease has to be considered and excluded. CONCLUSION: As randomized controlled treatment trials are still missing in vestibular migraine, the therapeutic recommendations for vestibular migraine are currently based on the guidelines of migraine.

Pathophysiology of hypnic headache.

BACKGROUND: Hypnic headache (HH) is a rare primary headache disorder that is characterized by strictly sleep related headache attacks. PURPOSE: The underlying pathophysiology of HH is mainly enigmatic but some clinical characteristics such as circadian rhythmicity and caffeine responsiveness may point toward possible underlying mechanisms. METHOD: Current studies that deal with the pathophysiology of HH are summarized. Data on cerebral imaging, sleep, electrophysiology studies, effectiveness of drugs, and symptomatic headache types are discussed to illuminate underlying pathophysiologic mechanisms. CONCLUSION: HH can be clearly differentiated by its clinical presentation as well as imaging and electrophysiological study results from other primary headaches such as migraine or cluster headache. The underlying pathophysiology is still enigmatic but a hypothalamic involvement seems to be likely.

Central vestibular system modulation in vestibular migraine.

BACKGROUND: Vestibular migraine affects 1% of the general population, and 30%-50% of all migraine patients describe occasionally associated vertigo or dizziness. We aimed to identify brain regions altered in vestibular migraine in order to evaluate the connection between migraine and the vestibular system. METHODS: Seventeen patients with definite vestibular migraine were compared to 17 controls using magnetic resonance imaging-based voxel-based morphometry. RESULTS: We found grey matter (GM) volume reduction in the superior, inferior and middle (MT/V5) temporal gyrus as well as in the mid. cingulate, dorsolateral prefontal, insula, parietal and occipital cortex. A negative correlation of disease duration and GM volume was observed in areas associated with pain and vestibular processing. Moreover, there was a negative correlation between headache severity and prefrontal cortex volume. CONCLUSION: Alterations identified in vestibular migraine resemble those previously described for migraine, but also extend to areas involved in multisensory vestibular control and central vestibular compensation possibly representing the pathoanatomic connection between migraine and the vestibular system.

Structural imaging in cluster headache.

Cluster headache is a rare primary headache disorder and the most common trigeminal-autonomic cephalalgia. Even though it has been extensively studied, its pathophysiology remains nebulous. Over the last two decades, cerebral imaging has increasingly been used to aid the investigation of pain and headache disorders. Pioneering work using magnetic resonance-based, voxel-based morphometry depicted an isolated increase of grey matter in the posterior hypothalamus and thereby reconfirmed the most commonly accepted pathophysiological concept. More recent works demonstrate structural changes across multiple structures related to pain processing, sensory integration, and emotional evaluation. These changes do not seem to be static, but rather appear to be dynamic in nature as they change over the course of the disease. This was interpreted as a reflection of the plasticity of the human brain and should guide future thoughts towards a more complex pathophysiological model involving a maladaptive pain modulatory network.

Patient-conducted anodal transcranial direct current stimulation of the motor cortex alleviates pain in trigeminal neuralgia.

BACKGROUND: Transcranial direct current stimulation (tDCS) of the primary motor cortex has been shown to modulate pain and trigeminal nociceptive processing. METHODS: Ten patients with classical trigeminal neuralgia (TN) were stimulated daily for 20 minutes over two weeks using anodal (1 mA) or sham tDCS over the primary motor cortex (M1) in a randomized double-blind cross-over design. Primary outcome variable was pain intensity on a verbal rating scale (VRS 0-10). VRS and attack frequency were assessed for one month before, during and after tDCS. The impact on trigeminal pain processing was assessed with pain-related evoked potentials (PREP) and the nociceptive blink reflex (nBR) following electrical stimulation on both sides of the forehead before and after tDCS. RESULTS: Anodal tDCS reduced pain intensity significantly after two weeks of treatment. The attack frequency reduction was not significant. PREP showed an increased N2 latency and decreased peak-to-peak amplitude after anodal tDCS. No severe adverse events were reported. CONCLUSION: Anodal tDCS over two weeks ameliorates intensity of pain in TN. It may become a valuable treatment option for patients unresponsive to conventional treatment.