Peripheral neurostimulation for control of intractable occipital neuralgia

An Update on Non-Pharmacological Neuromodulation for the Acute and Preventive Treatment of Migraine

OBJECTIVE

To review current neuromodulation treatments available for migraine therapy, both in the acute and preventive setting.

METHODS

The published literature was reviewed for studies reporting the effects of different neuromodulation strategies in migraine with and without aura. The use of non-invasive: single pulse transcranial magnetic stimulation, non-invasive vagal nerve stimulation, supraorbital nerve stimulation, and transcranial direct current stimulation, as well as invasive methods such as occipital nerve stimulation and sphenopalatine ganglion stimulation, are assessed.

RESULTS

The available evidence shows that non-invasive techniques represent promising treatment strategies, whereas an invasive approach should only be used where patients are refractory to other preventives, including non-invasive methods.

CONCLUSIONS

Neuromodulation is emerging as an exciting approach to migraine therapy, especially in the context of failure of commonly used medicines or for patients who do not tolerate common side effects. More studies with appropriate blinding strategies are needed to confirm the results of these new treatment opportunities.

Novel technique for trialing peripheral nerve stimulation: ultrasonography-guided StimuCath trial

OBJECTIVE

Peripheral nerve stimulation (PNS) has been used for the treatment of neuropathic pain for many decades. Despite the specific indications for PNS, clinicians often have difficulty screening for candidates likely to have a good or fair outcome. Given the expense of a permanent implant, most insurance companies will not pay for the implant without a successful PNS trial. And since PNS has only recently been approved by the US Food and Drug Administration, many insurance companies will not pay for a conventional trial of PNS. The objective of this study is to describe a short low-cost method for trialing and screening patients for peripheral nerve stimulator implantation. Additionally, this study demonstrates the long-term efficacy of PNS in the treatment of chronic neuropathic pain and the relative effectiveness of this novel screening method.

METHODS

The records of all patients who had undergone trialing and implantation of a PNS system for chronic refractory pain at the authors' institution over a 1-year period (August 1, 2012–July 31, 2013) were examined in this retrospective case series. The search revealed 17 patients, 13 who had undergone a novel in-office ultrasonography-guided StimuCath screening technique and 4 who had undergone a traditional week-long screening procedure. All 17 patients experienced a successful PNS trial and proceeded to permanent PNS system implantation. Patients were followed up for a mean duration of 3.0 years. Visual analog scale (VAS) pain scores were used to assess pain relief in the short-term (< 6 weeks), at 1 year, and at the last follow-up. Final outcome was also characterized as good, fair, poor, or bad.

RESULTS

Of these 17 patients, 10 were still using their stimulator at the last follow-up, with 8 of them obtaining good relief (classified as ≥ 50% pain relief, with an average 81% reduction in the VAS score) and 2 patients attaining fair relief (< 50% relief but still using stimulation therapy). Among the remaining 7 patients, the stimulator had been explanted in 4 and there had been no relief in 3. Excluding explanted cases, follow-up ranged from 14 to 46 months, with an average of 36 months. Patients with good or fair relief had experienced pain prior to implantation for an average of 5.1 years (range 1.8–15.2 years). A longer duration of pain trended toward a poorer outcome (bad outcome 7.6 years vs good outcome 4.1 years, p = 0.03). Seven (54%) of the 13 patients with the shorter trial experienced a good or fair outcome with an average 79% reduction in the VAS score; however, all 4 of the bad outcome cases came from this group. Three (75%) of the 4 patients with the longer trial experienced a good or fair outcome at the last follow-up, with an average 54% reduction in the VAS score. There was no difference between the trialing methods and the proportion of favorable (good or fair) outcomes (p = 0.71).

CONCLUSIONS

Short, ultrasonography-guided StimuCath trials were feasible in screening patients for permanent implantation of PNS, with efficacy similar to the traditional week-long screening noted at the 3-year follow-up.

Review of Recent Advances in Peripheral Nerve Stimulation (PNS)

Peripheral nerve stimulation (PNS) for the treatment of chronic pain has become an increasingly important field in the arena of neuromodulation, given the ongoing advances in electrical neuromodulation technology since 1999 permitting minimally invasive approaches using an percutaneous approach as opposed to implantable systems. Our review aims to provide clinicians with the recent advances and studies in the field, with specific emphasis on clinical data and indications that have been accumulated over the last several years. In addition, we aim to address key basic science studies to further emphasize the importance of translational research outcomes driving clinical management.

Unilateral occipital nerve stimulation for bilateral occipital neuralgia: a case report and literature review

OBJECTIVES

The aim of this study is to present a case of successful relief of bilateral occipital neuralgia (ON) using unilateral occipital nerve stimulation (ONS) and to discuss the possible underlying mechanisms.

MATERIALS AND METHODS

We present the case of a 59-year-old female patient with severe bilateral ON treated with unilateral ONS. We systematically reviewed previous studies of ONS for ON, discussing the possible mechanisms of ONS in the relief of ON.

RESULTS

The patient reported complete pain relief after consistent unilateral ONS during the follow-up period. The underlying mechanisms may be linked to the relationship between pain and several brain regions, including the pons, midbrain, and periaqueductal gray.

CONCLUSION

ONS is an effective and safe option for treating ON. Future studies will be required to clarify the mechanisms by which unilateral occipital stimulation provided relief for bilateral neuralgia in this case.

Safety and Efficacy of Occipital Nerves Stimulation for the Treatment of Chronic Migraines: Randomized, Double-blind, Controlled Single-center Experience

BACKGROUND

A recent multicenter study presented 52-week safety and efficacy results from an open-label extension of a randomized, sham-controlled trial for patients with chronic migraine (CM) undergoing peripheral nerve stimulation of the occipital nerves. We present the data from a single center of 20 patients enrolled at the Cleveland Clinic's Pain Management Department.

METHODS

In this single center, 20 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 (AEs).

RESULTS

Headache days per month were reduced by 8.51 (±9.81) days (P < 0.0001). The proportion of patients who achieved a 30% and 50% reduction in headache days and/or pain intensity was 60% and 35%, respectively. MIDAS and Zung PAD were reduced for all patients. Fifteen (75%) of the 20 patients at the site reported at least one AE. A total of 20 AEs were reported from the site.

CONCLUSION

Our results support the 12-month efficacy of 20 CM patients receiving peripheral nerve stimulation of the occipital nerves in this single-center trial.

Trigemino-Cervical Neuropathic Pain Relieved by Serially Repeated Peripheral Nerve Field Stimulation Without Tolerance: Case Report

BACKGROUND

With its relative simplicity and safety, peripheral nerve field stimulation (PNFS; PENS) is contributing to the re-emergence of peripheral nerve stimulation as an effective therapy for neuropathic pain (NPP).

CASE PRESENTATION

A 70-year-old woman had developed severe, medically refractory NPP unilaterally in the scalp and face 20 years earlier, following a maxillofacial surgical procedure. PNFS gave substantial relief of the pain and allodynia and was repeated successfully on a further 25 occasions over the subsequent five years. Tolerance did not develop.

CONCLUSION

Serially repeated PNFS can provide sustained relief of NPP over long periods, without tolerance, where a permanent implant may be inappropriate, unavailable, or declined.

Occipital nerve stimulation improves the quality of life in medically-intractable chronic cluster headache: Results of an observational prospective study

Background Occipital nerve stimulation (ONS) has been proposed to treat chronic medically-intractable cluster headache (iCCH) in small series of cases without evaluation of its functional and emotional impacts. Methods We report the multidimensional outcome of a large observational study of iCCH patients, treated by ONS within a nationwide multidisciplinary network ( https://clinicaltrials.gov NCT01842763), with a one-year follow-up. Prospective evaluation was performed before surgery, then three and 12 months after. Results One year after ONS, the attack frequency per week was decreased >30% in 64% and >50% in 59% of the 44 patients. Mean (Standard Deviation) weekly attack frequency decreased from 21.5 (16.3) to 10.7 (13.8) ( p = 0.0002). About 70% of the patients responded to ONS, 47.8% being excellent responders. Prophylactic treatments could be decreased in 40% of patients. Functional (HIT-6 and MIDAS scales) and emotional (HAD scale) impacts were significantly improved, as well as the health-related quality of life (EQ-5D). The mean (SD) EQ-5D visual analogic scale score increased from 35.2 (23.6) to 51.9 (25.7) ( p = 0.0037). Surgical minor complications were observed in 33% of the patients. Conclusion ONS significantly reduced the attack frequency per week, as well as the functional and emotional headache impacts in iCCH patients, and dramatically improved the health-related quality of life of responders.

Cluster headache and other TACs: Pathophysiology and neurostimulation options

BACKGROUND

The trigeminal autonomic cephalalgias (TACs) are highly disabling primary headache disorders. There are several issues that remain unresolved in the understanding of the pathophysiology of the TACs, although activation of the trigeminal-autonomic reflex and ipsilateral hypothalamic activation both play a central role. The discovery of the central role of the hypothalamus led to its use as a therapeutic target. After the good results obtained with hypothalamic stimulation, other peripheral neuromodulation targets were tried in the management of refractory cluster headache (CH) and other TACs.

METHODS

This review is a summary both of CH pathophysiology and of efficacy of the different neuromodulation techniques.

RESULTS

In chronic cluster headache (CCH) patients, hypothalamic deep brain stimulation (DBS) produced a decrease in attack frequency of more than 50% in 60% of patients. Occipital nerve stimulation (ONS) also elicited favorable outcomes with a reduction of more than 50% of attacks in around 70% of patients with medically intractable CCH. Stimulation of the sphenopalatine ganglion (SPG) with a miniaturized implanted stimulator produced a clinically significant improvement in 68% of patients (acute, preventive, or both). Vagus nerve stimulation (VNS) with a portable device used in conjunction with standard of care in CH patients resulted in a reduction in the number of attacks. DBS and ONS have been used successfully in some cases of other TACs, including hemicrania continua (HC) and short-lasting unilateral headache attacks (SUNHA).

CONCLUSIONS

DBS has good results, but it is a more invasive technique and can generate serious adverse events. ONS has good results, but frequent and not serious adverse events. SPG stimulation (SPGS) is also efficacious in the acute and prophylactic treatment of refractory cluster headache. At this moment, ONS and SPG stimulation techniques are recommended as first line therapy in refractory cluster patients. New recent non-invasive approaches such as the non-invasive vagal nerve stimulator (nVNS) have shown efficacy in a few trials and could be an interesting alternative in the management of CH, but require more testing and positive randomized controlled trials.

Long-term outcomes of occipital nerve stimulation for chronic migraine: a cohort of 53 patients

Background

Chronic migraine affects up to 2 % of the general population and has a substantial impact on sufferers. Occipital nerve stimulation has been investigated as a potentially effective treatment for refractory chronic migraine. Results from randomised controlled trials and open label studies have been inconclusive with little long-term data available.

Methods

The long-term efficacy, functional outcome and safety of occipital nerve stimulation was evaluated in an uncontrolled, open-label, prospective study of 53 intractable chronic migraine patients.

Results

Fifty-three patients were implanted in a single centre between 2007 and 2013. Patients had a mean age of 47.75 years (range 26–70), had suffered chronic migraine for around 12 years and had failed a mean of 9 (range 4–19) preventative treatments prior to implant. Eighteen patients had other chronic headache phenotypes in addition to chronic migraine. After a median follow-up of 42.00 months (range 6–97) monthly moderate-to-severe headache days (i.e. days on which pain was more than 4 on the verbal rating score and lasted at least 4 h) reduced by 8.51 days (p < 0.001) in the whole cohort, 5.80 days (p < 0.01) in those with chronic migraine alone and 12.16 days (p < 0.001) in those with multiple phenotypes including chronic migraine. Response rate of the whole group (defined as a >30 % reduction in monthly moderate-to-severe headache days) was observed in 45.3 % of the whole cohort, 34.3 % of those with chronic migraine alone and 66.7 % in those with multiple headache types. Mean subjective patient estimate of improvement was 31.7 %. Significant reductions were also seen in outcome measures such as pain intensity (1.34 points, p < 0.001), all monthly headache days (5.66 days, p < 0.001) and pain duration (4.54 h, p < 0.001). Responders showed substantial reductions in headache-related disability, affect scores and quality of life measures. Adverse event rates were favourable with no episodes of lead migration and only one minor infection reported.

Conclusions

Occipital nerve stimulation may be a safe and efficacious treatment for highly intractable chronic migraine patients even after relatively prolonged follow up of a median of over 3 years.

Electronic supplementary material

The online version of this article (doi:10.1186/s10194-016-0659-0) contains supplementary material, which is available to authorized users.

Long-Term Clinical Outcome of Peripheral Nerve Stimulation for Chronic Headache and Complication Prevention

Background

Subcutaneous peripheral nerve stimulation (PNS) has emerged as a useful tool in the treatment of intractable headaches. However, complications such as skin erosion, infection and lead migration have adversely affected clinical outcome, and occasionally led to treatment cessation.

Objectives

Here we report the results of peripheral nerve stimulator implantation performed on 24 patients with various chronic headaches at our center over a period of 9 years. We describe the complications of the procedure and their prevention with a modified surgical technique.

Patients and Methods

We searched our database for patients with chronic refractory headaches who had undergone PNS. Patients were assessed before being considered for PNS, and their pain characteristics were reviewed. Following a successful trial, patients were implanted with a permanent peripheral nerve stimulator. Selection of target nerves was based on headache diagnosis and head pain characteristics. Patients were followed for an average of 4.9 years. Headache characteristics before and after treatment were compared.

Results

Twenty four patients were included in the study. All patients reported on improvement in head pain intensity, duration and frequency three months after permanent device implantation Mean total pain index (TPI) decreased significantly, from 516 ± 131 before the procedure to 74.8 ± 61.6 at the last follow up (P < 0.00001). There were no acute post-operative infections. Three patients had their stimulator removed. The self-rated treatment satisfaction was excellent in 54% of the patients, very good or good in 42%, and fair in 4%.

Conclusions

Our results support the use of PNS in some patients with refractory chronic headaches. Appropriate surgical planning and technique are important to achieve good clinical outcome and to minimize complications.

Long-term outcomes of intradural cervical dorsal root rhizotomy for refractory occipital neuralgia

OBJECT Occipital neuralgia (ON) causes chronic pain in the cutaneous distribution of the greater and lesser occipital nerves. The long-term efficacy of cervical dorsal root rhizotomy (CDR) in the management of ON has not been well described. The authors reviewed their 14-year experience with CDR to assess pain relief and functional outcomes in patients with medically refractory ON. METHODS A retrospective chart review of 75 ON patients who underwent cervical dorsal root rhizotomy, from 1998 to 2012, was performed. Fifty-five patients were included because they met the International Headache Society's (IHS) diagnostic criteria for ON, responded to CT-guided nerve blocks at the C-2 dorsal nerve root, and had at least one follow-up visit. Telephone interviews were additionally used to obtain data on patient satisfaction. RESULTS Forty-two patients (76%) were female, and the average age at surgery was 46 years (range 16-80). Average follow up was 67 months (range 5-150). Etiologies of ON included the following: idiopathic (44%), posttraumatic (27%), postsurgical (22%), post-cerebrovascular accident (4%), postherpetic (2%), and postviral (2%). At last follow-up, 35 patients (64%) reported full pain relief, 11 (20%) partial relief, and 7 (16%) no pain relief. The extent of pain relief after CDR was not significantly associated with ON etiology (p = 0.43). Of 37 patients whose satisfaction-related data were obtained, 25 (68%) reported willingness to undergo repeat surgery for similar pain relief, while 11 (30%) reported no such willingness; a single patient (2%) did not answer this question. Twenty-one individuals (57%) reported that their activity level/functional state improved after surgery, 5 (13%) reported a decline, and 11 (30%) reported no difference. The most common acute postoperative complications were infections in 9% (n = 5) and CSF leaks in 5% (n = 3); chronic complications included neck pain/stiffness in 16% (n = 9) and upper-extremity symptoms in 5% (n = 3) such as trapezius weakness, shoulder pain, and arm paresthesias. CONCLUSIONS Cervical dorsal root rhizotomy provides an efficacious means for pain relief in patients with medically refractory ON. In the appropriately selected patient, it may lead to optimal outcomes with a relatively low risk of complications.

Response to Occipital Nerve Block is Not Useful in Predicting Efficacy of Occipital Nerve Stimulation

Occipital nerve stimulation (ONS) may be effective for the treatment of headaches that are recalcitrant to medical therapy. The objective of this study was to determine if response to occipital nerve block (ONB) predicts response to ONS in patients with chronic, medically intractable headaches. We evaluated 15 patients who underwent placement of occipital nerve stimulators for the treatment of chronic headaches. Data were collected regarding analgesic response to ONB and to ONS. Nine of 15 patients were ONS responders (≥50% reduction in headache frequency or severity). Thirteen patients had ONB prior to stimulator implantation. Ten of 13 who had ONB had significant relief of head pain lasting at least 24 h, and three were ONB non-responders. Of the three ONB non-responders, two were ONS responders. Of the two patients who did not have ONB prior to ONS, one was an ONS responder and one was an ONS non-responder. In conclusion, analgesic response to ONB may not be predictive of the therapeutic effect from ONS in patients with medically refractory chronic headaches.

Endoventricular Deep Brain Stimulation of the Third Ventricle

BACKGROUND:

The third ventricle (3rd V) is surrounded by centers related to satiety, homeostasis, hormones, sleep, memory, and pain. Stimulation of the wall of the 3rd V could be useful to treat disorders related to dysfunction of the hypothalamus.

OBJECTIVE:

To assess safety and efficacy of endoventricular electrical stimulation of the hypothalamus using a floating deep brain stimulation (DBS) lead laid on the floor of the 3rd V to treat refractory cluster headaches (CH).

METHODS:

Seven patients, aged 24 to 60 years, experiencing chronic CH (mean chronic duration 5.8 ± 2.5 years) were enrolled in this pilot, prospective, open study assessing the safety and potential efficacy of chronic DBS of the 3rd V. Number of attacks was collected during baseline and was compared with those occurring at 3, 6, and 12 months postoperation. Any side effects that occurred during or after surgery were reported. Effect on mood was assessed using the Hospital Anxiety and Depression scale during baseline and at 6 and 12 months postoperation.

RESULTS:

Insertion of the lead into the posterior 3rd V and chronic stimulation was feasible and safe in all patients. The voltage ranged from 0.9 to 2.3 volts. The most common side effect was transient trembling vision during stimulation. At 12 months, 3 of 7 patients were pain free, 2 had 90% improvement, 1 of 7 had 75% improvement, and 1 of 7 was not significantly improved.

CONCLUSION:

This proof of concept demonstrates the feasibility, safety, and potential efficacy of 3rd V DBS using an endoventricular road that could be applied to treat various diseases involving hypothalamic areas.

Neuralgias of the Head: Occipital Neuralgia

Occipital neuralgia is defined by the International Headache Society as paroxysmal shooting or stabbing pain in the dermatomes of the greater or lesser occipital nerve. Various treatment methods exist, from medical treatment to open surgical procedures. Local injection with corticosteroid can improve symptoms, though generally only temporarily. More invasive procedures can be considered for cases that do not respond adequately to medical therapies or repeated injections. Radiofrequency lesioning of the greater occipital nerve can relieve symptoms, but there is a tendency for the pain to recur during follow-up. There also remains a substantial group of intractable patients that do not benefit from local injections and conventional procedures. Moreover, treatment of occipital neuralgia is sometimes challenging. More invasive procedures, such as C2 gangliotomy, C2 ganglionectomy, C2 to C3 rhizotomy, C2 to C3 root decompression, neurectomy, and neurolysis with or without sectioning of the inferior oblique muscle, are now rarely performed for medically refractory patients. Recently, a few reports have described positive results following peripheral nerve stimulation of the greater or lesser occipital nerve. Although this procedure is less invasive, the significance of the results is hampered by the small sample size and the lack of long-term data. Clinicians should always remember that destructive procedures carry grave risks: once an anatomic structure is destroyed, it cannot be easily recovered, if at all, and with any destructive procedure there is always the risk of the development of painful neuroma or causalgia, conditions that may be even harder to control than the original complaint.

Occipital Nerve Stimulation for the Treatment of Patients With Medically Refractory Occipital Neuralgia: Congress of Neurological Surgeons Systematic Review and Evidence-Based Guideline

BACKGROUND

Occipital neuralgia (ON) is a disorder characterized by sharp, electrical, paroxysmal pain, originating from the occiput and extending along the posterior scalp, in the distribution of the greater, lesser, and/or third occipital nerve. Occipital nerve stimulation (ONS) constitutes a promising therapy for medically refractory ON because it is reversible with minimal side effects and has shown continued efficacy with long-term follow-up.

OBJECTIVE

To conduct a systematic literature review and provide treatment recommendations for the use of ONS for the treatment of patients with medically refractory ON.

METHODS

A systematic literature search was conducted using the PubMed database and the Cochrane Library to locate articles published between 1966 and April 2014 using MeSH headings and keywords relevant to ONS as a means to treat ON. A second literature search was conducted using the PubMed database and the Cochrane Library to locate articles published between 1966 and June 2014 using MeSH headings and keywords relevant to interventions that predict response to ONS in ON. The strength of evidence of each article that underwent full text review and the resulting strength of recommendation were graded according to the guidelines development methodology of the American Association of Neurological Surgeons/Congress of Neurological Surgeons Joint Guidelines Committee.

RESULTS

Nine studies met the criteria for inclusion in this guideline. All articles provided Class III Level evidence.

CONCLUSION

Based on the data derived from this systematic literature review, the following Level III recommendation can be made: the use of ONS is a treatment option for patients with medically refractory ON.

A good preoperative response to transcutaneous electrical nerve stimulation predicts a better therapeutic effect of implanted occipital nerve stimulation in pharmacologically intractable headaches

Occipital nerve stimulation (ONS) is a surgical approach to treat patients with medically intractable chronic headache disorders. However, no preoperative test has been yet validated to allow candidates to be selected for implantation. In this study, the analgesic efficacy of transcutaneous electrical nerve stimulation (TENS) was tested for 1 to 3 months in 41 patients with pharmacologically intractable headache disorders of various origins, using a new technique of electrode placement over the occipital nerve. ONS electrodes were subsequently implanted in 33 patients (occipital neuralgia [n=15], cervicogenic headache [n=7], cluster headache [n=6], chronic migraine [n=5]) who had responded at least moderately to TENS. Assessment was performed up to five years after implantation (three years on average), based on the mean and maximum daily pain intensity scored on a 0-10 visual analogue scale and the number of headache days per month. Both TENS and chronic ONS therapy were found to be efficacious (57-76% improvement compared to baseline on the various clinical variables). The efficacy of ONS was better in cases of good or very good preoperative response to TENS than in cases of moderate response to TENS. Implanted ONS may be a valuable therapeutic option in the long term for patients with pharmacologically intractable chronic headache. Although we cannot conclude in patients with poor or no response to TENS, a good or very good response to TENS can support the indication of ONS therapy. This preoperative test could particularly be useful in patients with chronic migraine, in whom it may be difficult to indicate an invasive technique of cranial neurostimulation.

Implantable Neurostimulation for Headache Disorders: Effect on Healthcare Utilization and Expenditures

OBJECTIVES

Chronic daily headache is a considerable source of morbidity for patients and also carries an enormous economic burden. Patients who fail standard medication regimens lack well-defined therapies, and neurostimulation is an emerging option for these patients. The purpose of this study was to analyze the cost utility of implantable neurostimulation for treatment of headache.

METHODS

We utilized the Thompson Reuters Marketscan Data base to identify individuals diagnosed with headache disorders who underwent percutaneous neurostimulation. Healthcare expenditures for individuals who subsequently received permanent, surgically implanted neurostimulatory devices were compared to those who did not. Only individuals who sought implantable neurostimulation were included to account for headache severity. The cohorts were adjusted for comorbidity and prior headache-related expenses. Costs were modeled longitudinally using a generalized estimating equation.

RESULTS

A total of 579 patients who underwent percutaneous trial of neurostimulation were included, of which 324 (55.96%) converted to permanent neurostimulation within one year. Unadjusted expenditures were greater for patients who underwent conversion to the permanent neurostimulation device, as expected. Costs grew at a lower rate for patients who converted to permanent device implantation. Cost neutrality for patients receiving the permanent device was reached in less than five years after the enrollment date. The mean cost of conversion to a permanent implantation was $18,607.53 (SD $26,441.34).

CONCLUSIONS

Our study suggests that implantable neurostimulation reduces healthcare expenditures within a relatively short time period in patients with severe refractory headache.

New therapeutic approaches for the prevention and treatment of migraine

The management of patients with migraine is often unsatisfactory because available acute and preventive therapies are either ineffective or poorly tolerated. The acute treatment of migraine attacks has been limited to the use of analgesics, combinations of analgesics with caffeine, ergotamines, and the triptans. Successful new approaches for the treatment of acute migraine target calcitonin gene-related peptide (CGRP) and serotonin (5-hydroxytryptamine, 5-HT1F) receptors. Other approaches targeting the transient receptor potential vanilloid (TRPV1) receptor, glutamate, GABAA receptors, or a combination of 5-HT1B/1D receptors and neuronal nitric oxide synthesis have been investigated but have not been successful in clinical trials thus far. In migraine prevention, the most promising new approaches are humanised antibodies against CGRP or the CGRP receptor. Non-invasive and invasive neuromodulation approaches also show promise as both acute and preventive therapies, although further studies are needed to define appropriate candidates for these therapies and optimum protocols for their use.

Use of botulinum toxin injections to treat peripheral stimulator induced facial muscle twitching: a case report

Background

Facial pain can be a management challenge. Peripheral nerve/field stimulation may be an effective option for refractory cases, but direct muscle stimulation with facial twitching may result. Botulinum toxin injections have been used for blepharospasm and may be effective when facial stimulation results in unacceptable facial muscle twitching due to peripheral stimulation.

Case presentation

A 53-year old female suffered with chronic, refractory facial pain and migraines. Her facial pain began after a root canal of a left upper molar. She was trialed and then permanently implanted with a 1 × 8 sub-compact percutaneous stimulator lead, resulting in improved pain control and reduced medication use. However, she experienced blepharospasm whenever the amplitude was above 2.75 A. Therefore, she was treated with botulinum toxin injections into her bilateral cheek, face, temple and occiput. This treatment provided excellent relief of the facial spasms, allowing her to use her stimulator at high amplitudes, and thereby maximizing her pain relief. She received two subsequent treatments of botulinum toxin injections at 5-month intervals with similar results.

Conclusion

Peripheral nerve/field stimulation is being used for headaches and facial pain. An undesirable side effect of this emerging therapy is direct muscle stimulation. Botulinum toxin injections may be an effective treatment modality when stimulation techniques provide pain relief but also causes muscle twitching.

Transcutaneous Supraorbital Nerve Stimulation (t-SNS) with the Cefaly® Device for Migraine Prevention: A Review of the Available Data

So far, among the different non-invasive neurostimulation methods, only transcutaneous supraorbital nerve stimulation (t-SNS) with the Cefaly® (Cefaly Technology sprl, Herstal, Belgium) device has randomized controlled trial-based evidence for safety and efficacy and obtained American Food and Drug Administration approval for the prevention of episodic migraine. In a double-blinded, randomized, sham-controlled trial on 67 episodic migraine patients (mean pre-treatment migraine days/month: 6.9), the 50% responder rate after 3 months was significantly higher in the active group (38.2%) than in the sham group (12.1%); attack frequency and total headache days were also significantly reduced, but not headache severity. Acute anti-migraine drug intake was reduced by 36.7% in the active group. Statistical sub-analysis suggested that t-SNS was more effective in patients with a higher attack frequency. In a large survey on 2313 Cefaly users about safety and satisfaction only 4.3% of subjects reported side effects, all of which were minor and fully reversible, the most frequent being intolerance to the paresthesia feeling and the most severe an allergic skin reaction to the electrode gel. The efficacy/safety ratio of the Cefaly device was therefore most favorable, especially when compared to preventive anti-migraine drugs. The therapeutic efficacy of t-SNS with Cefaly with low-frequency migraine (≤5 attacks/month) was recently confirmed in an open randomized trial. No published data are available in chronic migraine. According to preliminary results of a fluorodeoxyglucose-positron emission tomography study, Cefaly might exert its effect in migraine by increasing activity in crucial areas of the limbic system and salience matrix such as orbitofrontal and anterior cingulate cortices.

Concordant occipital and supraorbital neurostimulation therapy for hemiplegic migraine; initial experience; a case series

INTRODUCTION

Hemiplegic migraine is a particularly severe form of the disease that often evolves to a debilitating chronic illness that is resistant to commonly available therapies. Peripheral neurostimulation has been found to be a beneficial therapy for some patients among several diagnostic classes of migraine, but its potential has not been specifically evaluated for hemiplegic migraine.

MATERIALS AND METHODS

Four patients with hemiplegic migraine were treated with concordant, combined occipital and supraorbital neurostimulation over periods ranging 6-92 months. The clinical indicators followed included assessments of headache frequency and severity, frequency of hemiplegic episodes, functional impairment, medication usage, and patient satisfaction.

RESULTS

All reported a positive therapeutic response, as their average headache frequency decreased by 92% (30 to 2.5 headache days/month); Visual Analog Score by 44% (9.5 to 5.3); frequency of hemiplegic episodes by 96% (7.5 to 0.25 hemiplegic episodes/month); headache medication usage by 96% (6 to 0.25 daily medications); and Migraine Disability Assessment score by 98% (249 to 6). All were satisfied and would recommend the therapy, and all preferred combined occipital-supraorbital neurostimulation to occipital neurostimulation alone.

CONCLUSIONS

Concordant combined occipital and supraorbital neurostimulation may provide effective therapy for both the pain and motor aura in some patients with hemiplegic migraine.

The appropriate use of neurostimulation: stimulation of the intracranial and extracranial space and head for chronic pain. Neuromodulation Appropriateness Consensus Committee

INTRODUCTION

The International Neuromodulation Society (INS) has identified a need for evaluation and analysis of the practice of neurostimulation of the brain and extracranial nerves of the head to treat chronic pain.

METHODS

The INS board of directors chose an expert panel, the Neuromodulation Appropriateness Consensus Committee (NACC), to evaluate the peer-reviewed literature, current research, and clinical experience and to give guidance for the appropriate use of these methods. The literature searches involved key word searches in PubMed, EMBASE, and Google Scholar dated 1970-2013, which were graded and evaluated by the authors.

RESULTS

The NACC found that evidence supports extracranial stimulation for facial pain, migraine, and scalp pain but is limited for intracranial neuromodulation. High cervical spinal cord stimulation is an evolving option for facial pain. Intracranial neurostimulation may be an excellent option to treat diseases of the nervous system, such as tremor and Parkinson's disease, and in the future, potentially Alzheimer's disease and traumatic brain injury, but current use of intracranial stimulation for pain should be seen as investigational.

CONCLUSIONS

The NACC concludes that extracranial nerve stimulation should be considered in the algorithmic treatment of migraine and other disorders of the head. We should strive to perfect targets outside the cranium when treating pain, if at all possible.

Treatment of cervicogenic headache with cervical epidural steroid injection

Cervicogenic headache (CGH) is defined as referred pain from various cervical structures innervated by the upper three cervical spinal nerves. Such structures are potential pain generators, and include the atlanto-occipital joint, atlantoaxial joint, C2-3 zygapophysial joint, C2-3 intervertebral disc, cervical myofascial trigger points, as well as the cervical spinal nerves. Various interventional techniques, including cervical epidural steroid injection (CESI), have been proposed to treat this disorder. And while steroids administered by cervical epidural injection have been used in clinical practice to provide anti-inflammatory and analgesic effects that may alleviate pain in patients with CGH, the use of CESI in the diagnosis and treatment of CGH remains controversial. This article describes the neuroanatomy, neurophysiology, and classification of CGH as well as a review of the available literature describing CESI as treatment for this debilitating condition.

Novel High-Frequency Peripheral Nerve Stimulator Treatment of Refractory Postherpetic Neuralgia: A Brief Technical Note

OBJECTIVES

The study aims to describe an ultrasound (US)-guided peripheral nerve stimulation implant technique and describe the effect of high-frequency peripheral nerve stimulation on refractory postherpetic neuralgia.

MATERIALS AND METHODS

Following a cadaver pilot trial using US and confirmatory fluoroscopic guidance, a 52-year-old man with refractory left supraorbital neuralgia underwent combined US and fluoroscopic-guided supraorbital peripheral nerve stimulator trial. The patient was subsequently implanted with a percutaneous lead over the left supraorbital and supratrochlear nerve utilizing a high-frequency stimulation paradigm.

RESULTS

At 9 months follow-up, the pain intensity had declined from a weekly average of 8/10 to 1/10 on the pain visual analog scale (VAS). After implant, both nerve conduction and blink reflex studies were performed, which demonstrated herpetic nerve damage and frequency-specific peripheral nerve stimulation effects. The patient preferred analgesia in the supraorbital nerve distribution accomplished with high-frequency paresthesia-free stimulation (HFS) at an amplitude of 6.2 mA, a frequency of 100-1200 Hz, and a pulse width of 130 μsec, to paresthesia-mediated pain relief associated with low-frequency stimulation.

CONCLUSION

We report the implant of a supraorbital peripheral nerve stimulating electrode that utilizes a high-frequency program resulting in sustained suppression of intractable postherpetic neuralgia.

Targeting pericranial nerve branches to treat migraine: Current approaches and perspectives

BACKGROUND

Migraine is a highly prevalent neurological disorders and a major individual and societal burden. Migraine is not curable at the present time, but it is amenable to acute symptomatic and preventive pharmacotherapies.

SUMMARY

Since the latter are frequently unsatisfactory, other treatment strategies have been used or are being explored. In particular, interventions targeting pericranial nerves are now part of the migraine armamentarium. We will critically review some of them, such as invasive and noninvasive neurostimulation, therapeutic blocks and surgical decompressions.

CONCLUSIONS

Although current knowledge on migraine pathophysiology suggests a central nervous system dysfunction, there is some evidence that interventions targeting peripheral nerves are able to modulate neuronal circuits involved in pain control and that they could be useful in some selected patients. Larger, well-designed and comparative trials are needed to appraise the respective advantages, disadvantages and indications of most interventions discussed here.

Diagnosis, pathophysiology and management of chronic migraine: a proposal of the Belgian Headache Society

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.

Neuromodulation in migraine: state of the art and perspectives

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.

Occipital nerve stimulation

Occipital nerve stimulation (ONS) is a form of neuromodulation therapy aimed at treating intractable headache and craniofacial pain. The therapy utilizes neurostimulating electrodes placed subcutaneously in the occipital region and connected to a permanently implanted programmable pulse generator identical to those used for dorsal column/spinal cord stimulation. The presumed mechanisms of action involve modulation of the trigeminocervical complex, as well as closure of the physiologic pain gate. ONS is a reversible, nondestructive therapy, which can be tailored to a patient's individual needs. Typically, candidates for successful ONS include those patients with migraines, Chiari malformation, or occipital neuralgia. However, recent MRSA infections, unrealistic expectations, and psychiatric comorbidities are generally contraindications. As with any invasive procedure, complications may occur including lead migration, infection, wound erosion, device failure, muscle spasms, and pain. The success of this therapy is dependent on careful patient selection, a preimplantation trial, meticulous implantation technique, programming strategies, and complication avoidance.

Neuromodulation in cluster headache

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.

The surgical technique of occipital nerve stimulation

BACKGROUND

Occipital nerve stimulation is increasingly used in the treatment of primary headache disorders. We describe a surgical technique applying preoperative fluoroscopy and intraoperative tactile orientation designed to reduce radiation exposure and provide reproducible results.

METHOD

Under general anesthesia and in the supine position, the C1-C2 transition is identified fluoroscopically and marked with an electrocardiogram (ECG) electrode prior to surgery. During electrode placement, the ECG electrodes are used for tactile orientation of electrode direction and depth.

CONCLUSIONS

The use of tactile orientation solely during surgery reduces radiation exposure and decreases the duration of surgery. This technique allows reproducible results of final electrode position.

A systematic review of peripheral nerve interventional treatments for chronic headaches

OBJECTIVE

This study aimed to systematically compare the outcomes of different types of interventional procedures offered for the treatment of headaches and targeted toward peripheral nerves based on available published literature.

BACKGROUND

Multiple procedural modalities targeted at peripheral nerves are being offered to patients for the treatment of chronic headaches. However, few resources exist to compare the effectiveness of these modalities. The objective of this study was to systematically review the literature to compare the published outcomes and effectiveness of peripheral nerve surgery, radiofrequency (RF) therapy, and peripheral nerve stimulators for chronic headaches, migraines, and occipital neuralgia.

METHODS

A broad literature search of the MEDLINE and CENTRAL (Cochrane) databases was undertaken. Relevant studies were selected by 2 independent reviewers and these results were narrowed further by the application of predetermined inclusion and exclusion criteria. Studies were assessed for quality, and data were extracted regarding study characteristics (study type, level of evidence, type of intervention, and number of patients) and objective outcomes (success rate, length of follow-up, and complications). Pooled analysis was performed to compare success rates and complications between modality types.

RESULTS

Of an initial 250 search results, 26 studies met the inclusion criteria. Of these, 14 articles studied nerve decompression, 9 studied peripheral nerve stimulation, and 3 studied RF intervention. When study populations and results were pooled, a total of 1253 patients had undergone nerve decompression with an 86% success rate, 184 patients were treated by nerve stimulation with a 68% success rate, and 131 patients were treated by RF with a 55% success rate. When compared to one another, these success rates were all statistically significantly different. Neither nerve decompression nor RF reported complications requiring a return to the operating room, whereas implantable nerve stimulators had a 31.5% rate of such complications. Minor complication rates were similar among all 3 procedures.

CONCLUSIONS

Of the 3 most commonly encountered interventional procedures for chronic headaches, peripheral nerve surgery via decompression of involved peripheral nerves has been the best-studied modality in terms of total number of studies, level of evidence of published studies, and length of follow-up. Reported success rates for nerve decompression or excision tend to be higher than those for peripheral nerve stimulation or for RF, although poor study quantity and quality prohibit an accurate comparative analysis. Of the 3 procedures, peripheral nerve stimulator implantation was associated with the greatest number of complications. Although peripheral nerve surgery seems to be the interventional treatment modality that is currently best supported by the literature, better controlled and normalized high-quality studies will help to better define the specific roles for each type of intervention.

Spinal cord stimulation for neuropathic pain: current perspectives

Neuropathic pain constitutes a significant portion of chronic pain. Patients with neuropathic pain are usually more heavily burdened than patients with nociceptive pain. They suffer more often from insomnia, anxiety, and depression. Moreover, analgesic medication often has an insufficient effect on neuropathic pain. Spinal cord stimulation constitutes a therapy alternative that, to date, remains underused. In the last 10 to 15 years, it has undergone constant technical advancement. This review gives an overview of the present practice of spinal cord stimulation for chronic neuropathic pain and current developments such as high-frequency stimulation and peripheral nerve field stimulation.

Occipital neuralgia

Occipital pain is a common complaint amongst patients with headache, and the differential can include many primary headache disorders such as cervicogenic headache or migraine. Occipital neuralgia is an uncommon cause of occipital pain characterized by paroxysmal lancinating pain in the distribution of the greater, lesser or third occipital nerves. Greater occipital nerve blockade with anesthetics and/or corticosteroids can aid in confirming the diagnosis and providing pain relief. However, nerve blocks are also effective in migraine headache and misdiagnosis can result in a false positive. Physical therapy and preventive medication with antiepileptics and tricyclic antidepressants are often effective treatments for occipital neuralgia. Refractory cases may require intervention with pulsed radiofrequency or occipital nerve stimulation.

Peripheral neuromodulation: a review

Peripheral nerve stimulation (PNS) is likely the most diverse and rapidly expanding area of neuromodulation. Its expansion has become possible due to both technological and clinical advances in pain medicine. The first implantable systems were surgically placed. However, it is currently commonplace to use percutaneous leads, as this approach has become instrumental in its expansion. The first percutaneous peripheral nerve stimulators were reported in 1999. Cylindrical leads were implanted to stimulate the greater occipital nerve to manage intractable headache. It has been expanded into other individual nerves or nerve plexuses to treat neuropathic, visceral, cardiac, abdominal, low back and facial pain. The use of PNS in modulating organ function in treatment of syndromes such as epilepsy, incontinence and obesity with vagal, tibial and gastric stimulation is under extensive investigation. New technologies that allow easier and safer electrode placement are expected to further expand the uses of PNS. A noninvasive stimulation will open this treatment modality to more clinicians of varying backgrounds.