Occipital nerve stimulation for chronic migraine: already advised?

Changes in peripheral and central sensitization in patients undergoing occipital nerve stimulation

Introduction

Central sensitization and impaired conditioned pain modulation (CPM) response have been reported to contribute to migraine progression. Migraine patients can present with allodynia possibly attributed to increased sensitivity of peripheral ends of nociceptors with both peripheral and central sensitization. Occipital nerve stimulation (ONS) works by stimulating the distal branches of C1, C2 and C3 possibly altering the nociceptive traffic to the trigemino-cervical complex, brainstem and supranuclear connections.

Aims

This observational study explores peripheral and central sensitization in patients undergoing percutaneous ONS.

Methods

Following local regulatory approval, 13 patients undergoing ONS with dual Octrode 90 cm leads and rechargeable implantable pulse generator (IPG) (St Jude) were recruited to have quantitative sensory testing (QST) pre- and post-procedure 2 weeks, 1, 3, 6 and 12 months.

Results

Patients with intractable migraine demonstrated impaired CPM (mean baseline pressure pain thresholds (PPTs): 61.98 kPa vs 48.01 kPa cuff inflated) prior to ONS, reverting to an efficient CPM response within 2 weeks following ONS implant (68.9 kPa vs 104.5 kPa cuff inflated) and continuing positively over the next 12 months. In contrast, no statistical difference was observed in PPTs.

Conclusion

This is the first reported observation highlighting the effects on central sensitization following ONS. A consistent and sustained improvement in CPM was observed in contrast to PPT's where there was no difference. Normalisation of the CPM response following ONS indicates that the treatment may reduce central sensitization in the migraine population.

Botulinum toxin A (BT-A) versus low-level laser therapy (LLLT) in chronic migraine treatment: a comparison

OBJECTIVE

The aim of this work was to evaluate patients with chronic migraine treated with botulinum toxin A (BT-A) and compare this with low level laser therapy (LLLT), referencing: pain days, pain intensity, intake of drugs/self-medication, anxiety and sleep disorders.

METHODS

Patients were randomized into two groups: BT-A group (n = 18) and LLLT group (n = 18). Each patient kept three pain diaries: one before (baseline) (30 days), one during treatment (30 days) and one after the post-treatment phase (30 days). Repeated ANOVA plus the Bonferroni post-test, Student's t test, and factorial analysis were applied, and p < 0.05 was accepted as significant.

RESULTS

Our data showed that both treatments were able to reduce headache days, acute medication intake and decrease the intensity of pain. Anxiety was reduced in the BT-A group, while sleep disturbance was reduced in the LLLT group.

CONCLUSION

Our data showed that both treatments can be used to treat chronic migraine, without notable differences between them.

Efficacy of Pulsed Radiofrequency on Cervical 2-3 Posterior Medial Branches in Treating Chronic Migraine: A Randomized, Controlled, and Double-Blind Trial

Objective. The aim of this study was to examine the efficacy and safety of pulsed radiofrequency (PRF) in the treatment of chronic migraine (CM) on cervical 2-3 posterior medial branches. Methods. This randomized, double-blind, and controlled clinical trial included 40 subjects with CM, who were randomly divided into two groups: treatment (treated by PRF) and sham (treated by sham treatment). Pain intensity, headache duration (days), the Migraine Disability Assessment Questionnaire (MIDAS), and aspirin dose taken by patients were evaluated at 1, 2, and 6 months after the intervention. Side effects were observed from the time of treatment and throughout the follow-up period. Results. During the follow-up, pain intensity, headache duration (days), disability score, and the analgesic dose were significantly improved in the treatment group compared to the sham group (P < 0.001) and the baseline (P < 0.001) at all measured time points after intervention. No serious complications were reported. Conclusion. PRF on the cervical 2-3 posterior medial branches could provide satisfactory efficacy in the treatment of CM without obvious adverse effects.

Occipital Nerve Stimulation for Migraine: A Systematic Review

Patients who suffer from migraines often report impaired quality of life. Occipital nerve stimulation (ONS) is a novel treatment modality for migraines, although few systematic reviews have evaluated whether this therapy is efficacious. The objective of this study was to evaluate the clinical efficacy and safety of ONS for treating migraine through a literature review. We performed a literature search to identify studies that investigated ONS for migraine treatment. Evidence levels of these studies were assessed by recommendations set by the University of Oxford Centre for Evidence-Based Medicine. Five randomized controlled trials, 4 retrospective studies, and one prospective study met the inclusion criteria. Results from the retrospective studies and case series indicated that ONS significantly reduced the pain intensity and the number of days with headache in patients with migraine. However, the evidence of ONS efficacy established by randomized controlled trials was limited. Improvement in the migraine disability assessment (MIDAS) score was more dramatic than improvement in the SF-36 score at follow-up. The mean complication incidence of ONS was 66% for the reviewed studies. Future clinical studies should optimize and standardize the ONS intervention process and identify the relationship among the surgical process, efficacy, and complications resulting from the procedure.

Safety and efficacy of peripheral nerve stimulation of the occipital nerves for the management of chronic migraine: long-term results from a randomized, multicenter, double-blinded, controlled study

BACKGROUND

Recent studies evaluated short-term efficacy and safety of peripheral nerve stimulation (PNS) of the occipital nerves for managing chronic migraine. We present 52-week safety and efficacy results from an open-label extension of a randomized, sham-controlled trial.

METHODS

In this institutional review board-approved, randomized, multicenter, double-blinded study, patients were implanted with a neurostimulation system, randomized to an active or control group for 12 weeks, and received open-label treatment for an additional 40 weeks. Outcomes collected included number of headache days, pain intensity, migraine disability assessment (MIDAS), Zung Pain and Distress (PAD), direct patient reports of headache pain relief, quality of life, satisfaction and adverse events. Statistical tests assessed change from baseline to 52 weeks using paired t-tests. Intent-to-treat (ITT) analyses of all patients (N = 157) and analyses of only patients who met criteria for intractable chronic migraine (ICM; N = 125) were performed.

RESULTS

Headache days were significantly reduced by 6.7 (±8.4) days in the ITT population (p < 0.001) and by 7.7 (±8.7) days in the ICM population (p < 0.001). The percentages of patients who achieved a 30% and 50% reduction in headache days and/or pain intensity were 59.5% and 47.8%, respectively. MIDAS and Zung PAD scores were significantly reduced for both populations. Excellent or good headache relief was reported by 65.4% of the ITT population and 67.9% of the ICM population. More than half the patients in both cohorts were satisfied with the headache relief provided by the device. A total of 183 device/procedure-related adverse events occurred during the study, of which 18 (8.6%) required hospitalization and 85 (40.7%) required surgical intervention; 70% of patients experienced an adverse event.

CONCLUSION

Our results support the 12-month efficacy of PNS of the occipital nerves for headache pain and disability associated with chronic migraine. More emphasis on adverse event mitigation is needed in future research.

TRIAL REGISTRATION

Clinical trials.gov (NCT00615342).

Neurostimulators for the treatment of primary headaches

Neurostimulation techniques have increased our therapeutic armamentarium, providing additional options for the treatment of patients with drug-resistant headache. Occipital nerve stimulation can be considered in drug-resistant chronic cluster headache and, with more caution, in drug-resistant chronic migraine. Approximately 12 years after its introduction, hypothalamic stimulation is a valid option for drug-resistant chronic cluster headache to be considered when occipital nerve stimulation fails. Several other peripheral stimulation approaches (in addition to occipital nerve stimulation) have been introduced in recent years; however, for the most part, appropriate studies supporting their efficacy are lacking. Transcranial magnetic stimulation, transcutaneous supraorbital nerve stimulation, sphenopalatine ganglion stimulation and vagal nerve stimulation have all been tried, but results are not wholly convincing, and more extensive evaluations are required.

Transient localized wave patterns and their application to migraine

Transient dynamics is pervasive in the human brain and poses challenging problems both in mathematical tractability and clinical observability. We investigate statistical properties of transient cortical wave patterns with characteristic forms (shape, size, duration) in a canonical reaction-diffusion model with mean field inhibition. The patterns are formed by ghost behavior near a saddle-node bifurcation in which a stable traveling wave (node) collides with its critical nucleation mass (saddle). Similar patterns have been observed with fMRI in migraine. Our results support the controversial idea that waves of cortical spreading depression (SD) have a causal relationship with the headache phase in migraine and, therefore, occur not only in migraine with aura (MA), but also in migraine without aura (MO), i.e., in the two major migraine subtypes. We suggest a congruence between the prevalence of MO and MA with the statistical properties of the traveling waves' forms according to which two predictions follow: (i) the activation of nociceptive mechanisms relevant for headache is dependent upon a sufficiently large instantaneous affected cortical area; and (ii) the incidence of MA is reflected in the distance to the saddle-node bifurcation. We also observed that the maximal instantaneous affected cortical area is anticorrelated to both SD duration and total affected cortical area, which can explain why the headache is less severe in MA than in MO. Furthermore, the contested notion of MO attacks with silent aura is resolved. We briefly discuss model-based control and means by which neuromodulation techniques may affect pathways of pain formation.