Occipital nerve stimulation for medically refractory hypnic headache

The effect of TENS on sleep: A pilot study

BACKGROUND

Insomnia is the second most common neuropsychiatric disorder, but the current treatments are not very effective. There is therefore an urgent need to develop better treatments. Transcutaneous electrical nerve stimulation (TENS) may be a promising means of treating insomnia.

OBJECTIVE

This work aims to explore whether and how TENS modulate sleep and the effect of stimulation waveforms on sleep.

METHODS

Forty-five healthy subjects participated in this study. Electroencephalography (EEG) data were recorded before and after four mode low-frequency (1 Hz) TENS with different waveforms, which were formed by superimposing sine waves of different high frequencies (60-210 Hz) and low frequencies (1-6 Hz). The four waveform modes are formed by combining sine waves of varying frequencies. Mode 1 (M1) consists of a combination of high frequencies (60-110 Hz) and low frequencies (1-6 Hz). Mode 2 (M2) is made up of high frequencies (60-210 Hz) and low frequencies (1-6 Hz). Mode 3 (M3) consists of high frequencies (110-160 Hz) and low frequencies (1-6 Hz), while mode 4 (M4) is composed of high frequencies (160-210 Hz) and low frequencies (1-6 Hz). For M1, M3 and M4, the high frequency portions of the stimulus waveforms account for 50%, while for M2, the high frequency portion of the waveform accounts for 65%. For each mode, the current intensities ranged from 4 mA to 7 mA, with values for each participant adjusted according to individual tolerance. During stimulation, the subjects were stimulated at the greater occipital nerve by the four mode TENS.

RESULTS

M1, M3, and M4 slowed down the frequency of neural activity, broadened the distribution of theta waves, and caused a decrease in activity in wakefulness-related regions and an increase in activity in sleep-related regions. However, M2 has the opposite modulation effect.

CONCLUSION

These results indicated that low-frequency TENS (1 Hz) may facilitate sleep in a waveform-specific manner. Our findings provide new insights into the mechanisms of sleep modulation by TENS and the design of effective insomnia treatments.

An unusual case of lead migration in occipital nerve stimulation: A case report and literature review

Background:

Lead migration is a complication associated with occipital nerve stimulation (ONS). We present a rare case in which fibrosis in the stress relief loop caused lead migration in the treatment of occipital neuralgia.

Case Description:

A 30-year-old woman with a 5-year history of refractory occipital neuralgia, who had been under ONS therapy for 2 months, presented with a sudden onset of typical occipital neuralgia pain associated with cervical muscles spasms and myoclonus. A skull radiography showed lead migration. The patient underwent surgery for lead repositioning. During surgery, we identified extensive fibrosis throughout the stress relief loop that produced several constriction points. The fibrosis in the stress relief loop increased tension on the lead during head-and-neck movement, causing progressive migration of the lead.

Conclusion:

Although lead migration is a common complication of ONS, its association with fibrosis in the stress relief loop has not, to the best of our knowledge, been reported before. Lead migration can directly affect treatment outcome and it is, therefore, important to fully understand the possible mechanisms that can cause it and how to promptly manage them.

[Peripheral neurostimulation in headache treatment]

According to rough estimates, at least one third of the population in developed countries suffers, to varying degrees, from certain forms of primary headache, the modern pharmacotherapy of which is not always effective and has a number of limitations. The non-pharmacological treatment of headache can be an alternative to the prescription of pharmacological agents and the only possible assistance option for patients developing drug-resistant cephalalgias. This review describes various methods of electrical neuromodulation that are used for the management of primary headaches. The authors provide information on current stages in implementation of implantable and non-invasive equipment into clinical practice, which makes possible electrical stimulations of peripheral nerves and of the sphenopalatine ganglion, as well as allows transcranial magnetic stimulation. Also the appearance and usage of portable electrical devices available on the world market are described, and mechanisms that can underlie anticephalgic action of neuromodulation therapy are discussed. Special attention is paid to the methods that are applied for electrostimulation of the vagus nerve and occipital nerves.

Peripheral Nerve Stimulation for Painful Mononeuropathy Secondary to Leprosy: A 12-Month Follow-Up Study

OBJECTIVE

Leprosy affects approximately 10-15 million patients worldwide and remains a relevant public health issue. Chronic pain secondary to leprosy is a primary cause of morbidity, and its treatment remains a challenge. We evaluated the feasibility and safety of peripheral nerve stimulation (PNS) for painful mononeuropathy secondary to leprosy that is refractory to pharmacological therapy and surgical intervention (decompression).

METHODS

Between 2011 and 2013 twenty-three patients with painful mononeuropathy secondary to leprosy were recruited to this prospective case series. All patients were considered to be refractory to optimized conservative treatment and neurosurgical decompression. Pain was evaluated over the course of the study using the neuropathic pain scale and the visual analog scale for pain. In the first stage, patients were implanted with a temporary electrode that was connected to an external stimulator, and were treated with PNS for seven days. Patients with 50% or greater pain relief received a definitive implantation in the second stage. Follow-ups in the second stage were conducted at 1, 3, 6, and 12 months.

RESULTS

After seven days of trial in the first stage, 10 patients showed a pain reduction of 50% or greater. At 12-month follow-up in the second stage, 6 of the 10 patients who underwent permanent device implantation showed a pain reduction of 50% or greater (75% reduction on average), and two patients showed a 30% reduction in pain. Two patients presented with electrode migration that required repositioning during the 12-month follow-up period.

CONCLUSIONS

Our data suggest that PNS might have significant long-term utility for the treatment of painful mononeuropathy secondary to leprosy. Future studies should be performed in order to corroborate our findings in a larger population and encourage the clinical implementation of this technique.

Inhibitory effect of high-frequency greater occipital nerve electrical stimulation on trigeminovascular nociceptive processing in rats

Electrical stimulation of the greater occipital nerve (GON) has recently shown promise as an effective non-pharmacological prophylactic therapy for drug-resistant chronic primary headaches, but the neurobiological mechanisms underlying its anticephalgic action are not elucidated. Considering that the spinal trigeminal nucleus (STN) is a key segmental structure playing a prominent role in pathophysiology of headaches, in the present study we evaluated the effects of GON electrical stimulation on ongoing and evoked firing of the dura-sensitive STN neurons. The experiments were carried out on urethane/chloralose-anesthetized, paralyzed and artificially ventilated male Wistar rats. Extracellular recordings were made from 11 neurons within the caudal part of the STN that received convergent input from the ipsilateral facial cutaneous receptive fields, dura mater and GON. In each experiment, five various combinations of the GON stimulation frequency (50, 75, 100 Hz) and intensity (1, 3, 6 V) were tested successively in 10 min interval. At all parameter sets, preconditioning GON stimulation (250 ms train of pulses applied before each recording) produced suppression of both the ongoing activity of the STN neurons and their responses to electrical stimulation of the dura mater. The inhibitory effect depended mostly on the GON stimulation intensity, being maximally pronounced when a stimulus of 6 V was applied. Thus, the GON stimulation-induced inhibition of trigeminovascular nociceptive processing at the level of STN has been demonstrated for the first time. The data obtained can contribute to a deeper understanding of neurophysiological mechanisms underlying the therapeutic efficacy of GON stimulation in primary headaches.

Hypnic headache: A review of clinical features, therapeutic options and outcomes

Background

Hypnic headache (HH), first reported in 1988, is a rare sleep-related headache disorder. In 2013 a new diagnostic criteria was proposed for HH in the International Classification of Headache Disorders, the third version beta (ICHD-3β).

Purpose

This review aimed to update the clinical characteristics, therapeutic options and clinical outcomes in patients with HH and also validate the new diagnostic criteria.

Methods

Based on a literature search in the major medical databases, we analyzed all case reports or case series on HH that have been published since the first description by Raskin. Except for symptomatic patients, all reported patients were included regardless of which diagnostic criteria were adopted. Four studies that reported the field-testing results of the ICHD-2 criteria were selected to validate the new ICHD-3β criteria.

Results

In total, 250 adult and five childhood patients are described in this review. The majority of patients were elderly and their ages of onset were typically more than 50 years old (92%). Approximately 7.7% of patients had some trigeminal autonomic features, which are not permitted in the ICHD-3β criteria. Compared with the ICHD-2 criteria, the diagnostic rate under the new criteria increased from 65% to 85% in recently reported cases. Randomized control trials both for acute and prophylactic treatment are lacking. Based on observational studies, the most effective acute treatment is caffeine and prophylactic medications in use are lithium, caffeine and indomethacin. Without treatment, the disease course is usually protracted but spontaneous remission did occur in 12 patients (4.8%). In those treated with prophylactic agents, no recurrence was noted in 43% of patients, even following withdrawal of medication.

Conclusions

The new ICHD-3β criteria are more sensitive and exhaustive for HH than the ICHD-2 criteria. Prophylactic treatment provides better outcomes; however, randomized controlled studies for treatment are needed to further verify the efficacy of the different drugs.

Supraorbital and supratrochlear stimulation for trigeminal autonomic cephalalgias

Trigeminal autonomic cephalalgias (TAC) is a rare primary headache disorder with challenging and limited treatment options for those unfortunate patients with severe and refractory pain. This article will review the conventional pharmacologic treatments as well as the new neuromodulation techniques designed to offer alternative and less invasive treatments. These techniques have evolved from the treatment of migraine headache, a much more common headache syndrome, and expanded towards application in patients with TAC. Specifically, the article will discuss the targeting of the supratrochlear and supraorbital nerves, both terminal branches of the trigeminal nerve.

Clinical utility of implantable neurostimulation devices in the treatment of chronic migraine

Chronic migraine is a disabling disorder that is costly to individuals and society. Occipital nerve stimulation has been used to treat refractory cases of primary headache disorders including drug-resistant chronic cluster headaches and chronic migraine. The Food and Drug Administration (FDA) off-labeled application of equipment used for peripheral nerve (occipital) stimulation is borrowed from FDA-labeled spinal cord stimulation. Manufacturer-sponsored randomized trials include a feasibility study (ONSTIM-Medtronic) and a safety and efficacy study (St Jude). A non-industry sponsored prospective, randomized crossover study by Serra and Marchiotretto suggests improved quality of life and a significant reduction in medication use. Though preliminary studies suggest occipital nerve stimulation is safe and efficacious in treating chronic migraine headache, complication rates, including lead migration, lead fracture, and surgical site infections remain high. Further studies are needed to demonstrate long-term outcomes, while improved surgical techniques and site-specific equipment are needed to minimize complications.

Hypnic headache

Background

Hypnic headache (HH) is a rare primary headache disorder that is characterised by strictly sleep-related headache attacks.

Purpose

Because of the low prevalence of this headache disorder, disease information is mainly based on case reports and small case series. This review summarises current knowledge on HH in regard to clinical presentation, pathophysiology, symptomatic causes and therapeutic options.

Method

We review all reported HH cases since its first description in 1988 by Raskin. Broadened diagnostic criteria were applied for patient selection that slightly deviate from the current ICHD-II criteria. Patients were allowed to describe the headache character to be other than dull. Additionally, accompanying mild trigemino-autonomic symptoms were permitted.

Conclusions

Mainly elderly patients are affected, but younger patients and even children might also suffer from HH. Headache attacks usually last between 15 and 180 minutes, but some patients report headache attacks up to 10 hours. Almost all patients report motor activity during headache attacks. Cerebral MRI and 24-hour blood pressure monitoring should be performed in the diagnostic work-up of HH. Other primary headache disorders such as migraine and cluster headache may also present with sleep-related headache attacks and should be considered first. Caffeine taken as a cup of strong coffee seems to be the best acute and prophylactic treatment option.

Hypnic headache: a review of 2012 publications

Hypnic headache is a rare primary headache disorder affecting middle age and above with a dull pain exclusively at nighttime. This article aims to review and discuss the most recent articles published in the year 2012 regarding hypnic headache. We will also discuss specific cases of pharmacological and nonpharmacologic successes in treating this rare disorder.

Neuromodulation for cephalgias

Headaches (cephalgias) are a common reason for patients to seek medical care. There are groups of patients with recurrent headache and craniofacial pain presenting with malignant course of their disease that becomes refractory to pharmacotherapy and other medical management options. Neuromodulation can be a viable treatment modality for at least some of these patients. We review the available evidence related to the use of neuromodulation modalities for the treatment of medically refractory craniofacial pain of different nosology based on the International Classification of Headache Disorders, 2(nd) edition (ICHD-II) classification. This article also reviews the scientific rationale of neuromodulation application in management of cephalgias.