Neurophysiological correlates of clinical improvement after greater occipital nerve (GON) block in chronic migraine: relevance for chronic migraine pathophysiology.

BACKGROUND: Therapeutic management of Chronic Migraine (CM), often associated with Medication Overuse Headache (MOH), is chiefly empirical, as no biomarker predicting or correlating with clinical efficacy is available to address therapeutic choices. The present study searched for neurophysiological correlates of Greater Occipital Nerve Block (GON-B) effects in CM. METHODS: We recruited 17 CM women, of whom 12 with MOH, and 19 healthy volunteers (HV). Patients had no preventive treatment since at least 3 months. After a 30-day baseline, they received a bilateral betamethasone-lidocaine GON-B of which the therapeutic effect was assessed 1 month later. Habituation of visual evoked potentials (VEP) and intensity dependence of auditory evoked potentials (IDAP) were recorded before and 1 week after the GON-B. RESULTS: At baseline, CM patients had a VEP habituation not different from HV, but a steeper IDAP value than HV (p = 0.01), suggestive of a lower serotonergic tone. GON-B significantly reduced the number of total headache days per month (- 34.9%; p = 0.003). Eight out 17CM patients reversed to episodic migraine and medication overuse resolved in 11 out of 12 patients. One week after the GON-B VEP habituation became lacking respect to baseline (p = 0.01) and to that of HV (p = 0.02) like in episodic migraine, while the IDAP slope significantly flattened (p < 0.0001). GON-B-induced reduction in headache days positively correlated with IDAP slope decrease (rho = 0.51, p = 0.03). CONCLUSIONS: GON-B may be effective in the treatment of CM, with or without MOH. The pre-treatment IDAP increase is compatible with a weak central serotonergic tone, which is strengthened after GON-B, suggesting that serotonergic mechanisms may play a role in CM and its reversion to episodic migraine. Since the degree of post-treatment IDAP decrease is correlated with clinical improvement, IDAP might be potentially useful as an early predictor of GON-B efficacy.

Neuroanatomical, Clinical and Cognitive Correlates of Post-Stroke Dysphagia.

BACKGROUND AND PURPOSE: About half of the dysphagic stroke patients have persistent swallowing dysfunction after 7 days from symptom onset. The aim of the study was to evaluate incidence, prognosis, clinical and neuroradiological correlates of post-stroke dysphagia. METHODS: We prospectively examined consecutive patients with acute ischemic or hemorrhagic stroke. Patients' clinical and neuroradiological data were collected. Swallowing function was assessed by the water swallow test upon admission and after 14 days; patients were then classified as persistent dysphagic, non-persistent dysphagic or non-dysphagic. RESULTS: We recruited 275 patients, 121 of whom were dysphagic upon admission and 254 patients attended follow-up at 14 days; 141 never presented dysphagia, 21 had a non-persistent pattern of dysphagia and 92 had a persistent one. Stroke type, leukoaraiosis degree, previous cognitive impairment and stroke severity upon admission independently predicted the occurrence of dysphagia after stroke and its persistence as well. At receiver operating characteristic (ROC) analysis, the National Institutes of Health Stroke Scale (NIHSS) score of 11.5 was the best predictive value of persistent dysphagia, with a specificity of 90.1% and a sensitivity of 72.4%. CONCLUSION: Stroke severity is an important predictor of a persistent pattern of dysphagia, with a suggested NIHSS cutoff value of ≥12. An independent correlation was observed with leukoaraiosis and with previous cognitive impairment.

Exploring the Therapeutic Potential of Quadripulse rTMS over the Visual Cortex: A Proof-of-Concept Study in Healthy Volunteers and Chronic Migraine Patients with Medication Overuse Headache.

In chronic migraine with medication overuse (CM-MOH), sensitization of visual cortices is reflected by (i) increased amplitude of stimulus-evoked responses and (ii) habituation deficit during repetitive stimulation. Both abnormalities might be mitigated by inhibitory transcranial neurostimulation. Here, we tested an inhibitory quadripulse repetitive transcranial magnetic stimulation (rTMS-QPI) protocol to decrease durably visual cortex excitability in healthy subjects (HS) and explored its therapeutic potential in CM-MOH patients. Pattern-reversal visual evoked potentials (VEP) were used as biomarkers of effect and recorded before (T1), immediately after (T2), and 3 h after stimulation (T3). In HS, rTMS-QPI durably decreased the VEP 1st block amplitude (p < 0.05) and its habituation (p < 0.05). These changes were more pronounced for the P1N2 component that was modified already at T2 up to T3, while for N1P1 they were significant only at T3. An excitatory stimulation protocol (rTMS-QPE) tended to have an opposite effect, restricted to P1N2. In 12 CM-MOH patients, during a four-week treatment (2 sessions/week), rTMS-QPI significantly reduced monthly headache days (p < 0.01). In patients reversing from CM-MOH to episodic migraine (n = 6), VEP habituation significantly improved after treatment (p = 0.005). rTMS-QPI durably decreases visual cortex responsivity in healthy subjects. In a proof-of-concept study of CM-MOH patients, rTMS-QPI also has beneficial clinical and electrophysiological effects, but sham-controlled trials are needed.

Occupational Therapy in Fatigue Management in Multiple Sclerosis: An Umbrella Review.

Background. Fatigue is one of the most invalidant symptoms of Multiple Sclerosis (MS) that negatively affects occupational and work performance and social participation. Occupational therapy (OT) assessment and treatment of impairments related to fatigue can have a significant and positive impact on the quality of life. Methods. An umbrella review has been carried out to provide rehabilitative decision makers in healthcare with insight into the role of OT in fatigue management in Multiple Sclerosis. The question is, what type of treatment provided by occupational therapist is more effective in reducing fatigue in Multiple Sclerosis? A search of literature published until June 2018 was undertaken by three independent reviewers using PubMed, PEDro, and Cochrane Library database including systematic reviews and meta-analyses of the last 10 years. Results. 10 studies were selected (5 systematic reviews, 1 meta-analysis, 3 reviews, and 1 guideline). Conclusions. Fatigue management programs have moderate evidence; other strategies such as OT strategies and telerehabilitation show low evidence.