Uncommon areas of electrical stimulation for pain relief

Assessment of Changes in Laryngeal Configuration and Voice Parameters Among Different Frequencies of Neuromuscular Electrical Stimulation (NMES) and Cumulative Effects of NMES in a Normophonic Subject: A Pilot Study

INTRODUCTION

Neuromuscular electrical stimulation (NMES) is a complementary resource to voice therapy that can be used for the treatment of hypofunctional voice disorders. Although positive clinical studies have been reported, neutral and even potentially harmful effects of NMES are also described in the literature. Furthermore, in the studies examined by the authors, the use of different methods of NMES have been identified, which further contributes to the inconsistent results found among studies. Moreover, limited rationale is provided for the chosen NMES parameters such as electrode placement, frequency of NMES and length of treatment. The aims of this pilot study were to investigate the a) impact of different frequencies of NMES on glottal configuration and vocal fold vibration patterns and b) changes in laryngeal configuration and vocal output across 12 minutes of NMES.

METHOD

Three experiments were carried out looking at changes in laryngeal configuration and voice output using different imaging techniques (fibreoptic nasolaryngoscopy and high-speed video), acoustical analysis (F0, formant analysis, SPL, CPPS and LHSR values), electroglottography (EGG) and Relative Fundamental Frequency (RFF) analyses. Glottal parameters and acoustical measures were recorded before, during, and after stimulation. Data was collected at rest and during phonation.

RESULTS

Overall the results showed global changes in laryngeal configuration from normal to hyperfunctional (ie, increased RFF, SPL, CQ, and stiffness). Changes were more pronounced for lower frequencies of NMES and were significant within less than three minutes of application.

CONCLUSION

NMES is an effective resource for the activation of intrinsic laryngeal muscles producing significant levels of adduction within few minutes of application. Lower NMES frequencies produced greater muscle activation when compared to higher frequencies.

Peripheral nerve stimulation: a percutaneous minimally invasive approach

We report on the use of a new percutaneous technique for peripheral nerve stimulation (PNS) treatment of chronic pain. A 56-year-old woman was diagnosed with algodystrophic syndrome, now called Complex Regional Pain Syndrome, type 2 (CRPS2), due to a lesion of the right medial nerve despite surgical revascularization, angioplasty and stent insertion. After a successful 10-day trial of PNS via a percutaneous quadripolar lead in the interscaline space, an implantable pulse generator was implanted in the abdominal subcutaneous tissue and connected to the subcutaneous lead via an extension. After one year of follow-up, the patient was still experiencing good pain relief. We conclude that this novel percutaneous PNS technique offers the advantage of being a minimally invasive approach that can be easily adopted for the management of chronic pain.

Occipital nerve stimulation for the treatment of occipital neuralgia-eight case studies

Objective.  The aim of this study was to examine the hypothesis that subcutaneous occipital stimulation influences pain due to occipital neuralgia. Materials and Methods.  Between 2001 and 2004 eight patients with intractable occipital neuralgia were referred to our center. Their records were reviewed. Each patient was interviewed over the telephone. They were all offered a trial of stimulation using a percutaneous lead over 1 week. If they achieved 50% pain reduction a permanent lead was implanted. The impact of occipital stimulation was measured by pain score, analgesic requirements, and employment status. Results.  Seven proceeded to a permanent stimulator. There was a reduction in the visual analog score postimplantation in five of the seven patients. The total quantity of opiates taken after implantation showed a marked reduction. Of the seven who had a permanent implant two acquired full-time employment. Conclusion.  Occipital neuralgia is a useful and reversible treatment for intractable occipital neuralgia.

Peripheral median nerve stimulation for the treatment of iatrogenic complex regional pain syndrome (CRPS) type II after carpal tunnel surgery

We report on the use and follow-up of direct peripheral nerve stimulation of the median nerve for the treatment of iatrogenic complex regional pain syndrome (CRPS). A 56-year-old woman presented with CRPS type II in the right forearm and hand, which had started after multiple carpal tunnel surgeries and had lasted for 2 years. The visual analogue scale (VAS) score was 8-10 out of 10. After a successful 15-day trial of median nerve peripheral nerve stimulation via a quadripolar lead in the right carpal tunnel space, an implantable pulse generator was inserted in the right infraclavicular space. The VAS score decreased to 1-2 out of 10 and the patient regained the ability to sleep. After 36 months of follow-up, the patient was still experiencing good pain relief without other treatment. We conclude that peripheral nerve stimulation is easy to use in pain management and could offer a valid treatment option for iatrogenic CRPS type II.

Peripheral nerve stimulation for neuropathic pain

Peripheral nerve stimulation (PNS) has been used for treatment of neuropathic pain for more than 40 years. Recent resurgence of interest to this elegant surgical modality came from the introduction of less invasive implantation techniques and the wider acceptance of neuromodulation as a treatment of medically refractory cases. This article reviews the literature on the use of PNS for neuropathic pain and describes current indications and hardware choices in frequent use. Published experience indicates that neuropathic pain responds to PNS in many patients. PNS works well in both established indications, such as post-traumatic and postsurgical neuropathy, occipital neuralgia, and complex regional pain syndromes, and in relatively new indications for neuromodulation, such as migraines and daily headaches, cluster headaches, and fibromyalgia. Future research and growing clinical experience will help in identifying the best candidates for PNS, choosing the best procedure and best hardware for each individual patient, and defining adequate expectations for patients and pain specialists.

Anesthetic management for surgical placement of greater occipital nerve stimulators in the treatment of primary headache disorders

We will present a case series looking at the anesthetic management of 4 patients undergoing surgical placement of greater occipital nerve stimulators for chronic headache. The anesthetic technique described uses total intravenous anesthesia with the guidance of Bispectral Index Scale to smoothen the transition between different anesthetic depths required for this novel operation.

Peripheral nerve stimulation for the treatment of neuropathic craniofacial pain

Treatment of neuropathic pain in the region of head and face presents a challenging problem for pain specialists. In particular, those patients who do not respond to conventional treatment modalities usually continue to suffer from pain due to lack of reliable medical and surgical approaches. Peripheral nerve stimulation (PNS) has been used for treatment of neuropathic pain for many decades, but only recently it has been systematically applied to the craniofacial region. Here we summarize published experience with PNS in treatment of craniofacial pain and discuss some technical details of the craniofacial PNS procedure.

Trigeminal and occipital peripheral nerve stimulation for craniofacial pain: a single-institution experience and review of the literature

OBJECT

Treatment of chronic neuropathic pain in the region of the head and face presents a challenge for pain specialists; patients who do not respond to conventional treatment modalities usually continue to suffer from pain due to the lack of reliable medical and surgical approaches. Peripheral nerve stimulation (PNS) has been used to treat neuropathic pain for many decades, but only recently has it been applied systematically to the craniofacial region. To advance the study of this treatment option, the authors present their initial experience with this approach, summarize published data on the use of PNS in treatment of craniofacial pain, and discuss some technical details of the craniofacial PNS procedure.

METHODS

A review of prospectively collected data in 30 patients who underwent PNS surgery for craniofacial pain was performed. The pain location, duration, cause, and previous treatments were analyzed, along with the surgical details, initial and long-term results, complications, and repeated operations. Stimulated nerves in this group included supraorbital (seven patients), infraorbital (six), and occipital (21); in 19 patients more than one nerve was stimulated. Twenty-two patients proceeded with implantation of a permanent system after the trial. Of these, at the time of the latest evaluation (mean follow-up duration 35 months), in two patients the devices had been removed because of pain improvement over time, in three the devices were removed due to loss of effectiveness (two cases) or late infection (one), and the rest are enjoying either complete (15 patients) or partial (two patients) pain relief. Three patients underwent repeated operation due to lead erosion, infection, or migration.

CONCLUSIONS

Peripheral nerve stimulation appears to be a safe and effective approach in the treatment of craniofacial neuropathic pain. The growing body of literature supports a wider acceptance of this approach in the field of pain surgery.

Spinal cord stimulation is an effective treatment for the chronic intractable visceral pelvic pain

OBJECTIVE

Recent studies have demonstrated significant involvement of dorsal column pathways in transmission of visceral pelvic pain. Spinal cord stimulation (SCS) suppresses visceral response to colon distension in an animal model and therefore may be an effective therapy for chronic pelvic pain of visceral origin. We are reporting on the value of neurostimulation for chronic visceral pelvic pain in six female patients with the diagnosis of long-standing pelvic pain (history of endometriosis, multiple surgical explorations, and dyspareunia).

DESIGN AND SETTINGS

Case-series report. All patients received repeated hypogastric blocks (in an average of 5.3 blocks) with a significant pain relief for a period ranging from 1 to 6 weeks. Three received neurolytic hypogastric block with the pain relief of 3, 8, and 12 months, respectively. Following psychological evaluation and clearance by our Multidisciplinary Committee on Implantable Devices, they all underwent SCS trial for 7-14 days. All patients received SCS systems with dual leads (Compact or Quad leads, Medtronic Inc., Minneapolis, MN, USA).

RESULTS

The average follow-up was 30.6 months. Median visual analog scale pain score decreased from 8 to 3. All patients had more than 50% of the pain relief. Pain Disability Index changed from an average of 57.7 +/- 12 to 19.5 +/- 7. Opiate use decreased from an average 22.5 mg to 6.6 mg of morphine sulfate milligram equivalents per day.

CONCLUSION

It appears that SCS may have a significant therapeutic potential for treatment of visceral pelvic pain.

Occipital nerve electrical stimulation via the midline approach and subcutaneous surgical leads for treatment of severe occipital neuralgia: a pilot study

Persistent occipital neuralgia can produce severe headaches that may not be controllable by conservative or surgical approaches. We describe a case series of 6 patients who had chronic headaches over an average of 4.9 yr who underwent occipital nerve electrical stimulation lead implantation using a modified midline approach. The patients had received conservative and surgical therapies in the past including oral antidepressants, membrane stabilizers, opioids, occipital nerve blocks, and radiofrequency ablations. Significant decreases in pain visual analog scale (VAS) scores and drastic improvement in functional capacity were observed during the occipital stimulation trial and during the 3-mo follow-up after implantation. The mean VAS score changed from 8.66 +/- 1.0 to 2.5 +/- 1.3 whereas pain disability index improved from 49.8 +/- 15.9 to 14.0 +/- 7.4. Our midline approach has several advantages compared with the submastoid approach used elsewhere. There is only one small midline incision over the upper neck and the strain on the lead extension occurs only with flexion and is minimal with lateral flexion and rotation, which contributes to overall stability of this system.

Cervicogenic headache: interventional, anesthetic, and ablative treatment

Cervicogenic headache is becoming an accepted clinical syndrome in which headache pain is thought to originate from the cervical spine. Unfortunately, there are no diagnostic imaging techniques of the cervical spine and associated structures that can determine the exact source of pain. Therefore, diagnosis and treatment are based on the major accepted criteria of clinical presentation and the use of diagnostic nerve blocks to identify the source of the pain generator before considering further interventional or neuroablative treatment. This suggests that consistent reproducible anatomic and neurophysiologic pathways exist for the reproduction of typical clinical pain patterns and the ability of neuroblockade to consistently interrupt these pain pathways. This article describes the essential anatomy required to understand the use of diagnostic nerve blocks, and their predictive value in anticipating response to neuroablative and interventional therapy with a review of the major interventional, anesthetic, and ablative techniques for cervicogenic headache.

Ganglionectomy of C-2 for the treatment of medically refractory occipital neuralgia

Occipital neuralgia is a result of neuropathic pain transmission in the distribution of the greater occipital nerve. Because it is well anatomically localized, occipital neuralgia has been the focus of various surgical treatments. Ablation, decompression, and modulation of the C-2 nerve have all been described as effective treatments. The C-2 dorsal root ganglionectomy provides effective treatment for this disorder with a low incidence of unpleasant side effects. In this review the authors summarize the current treatment of occipital neuralgia.