Stefano Palmisani

High-frequency spinal cord stimulation for the treatment of chronic back pain patients: results of a prospective multicenter European clinical study.

The objective of this prospective, open‐label, multicenter European clinical trial was to quantify the efficacy and safety of a spinal cord stimulation (SCS) system that utilizes high‐frequency (up to 10 kHz) waveforms, which do not produce paresthesia, for the treatment of chronic, intractable pain of the back and/or limbs.

Neuromodulation of chronic headaches: position statement from the European Headache Federation

The medical treatment of patients with chronic primary headache syndromes (chronic migraine, chronic tension-type headache, chronic cluster headache, hemicrania continua) is challenging as serious side effects frequently complicate the course of medical treatment and some patients may be even medically intractable. When a definitive lack of responsiveness to conservative treatments is ascertained and medication overuse headache is excluded, neuromodulation options can be considered in selected cases.Here, the various invasive and non-invasive approaches, such as hypothalamic deep brain stimulation, occipital nerve stimulation, stimulation of sphenopalatine ganglion, cervical spinal cord stimulation, vagus nerve stimulation, transcranial direct current stimulation, repetitive transcranial magnetic stimulation, and transcutaneous electrical nerve stimulation are extensively published although proper RCT-based evidence is limited. The European Headache Federation herewith provides a consensus statement on the clinical use of neuromodulation in headache, based on theoretical background, clinical data, and side effect of each method. This international consensus further gives recommendations for future studies on these new approaches.In spite of a growing field of stimulation devices in headaches treatment, further controlled studies to validate, strengthen and disseminate the use of neurostimulation are clearly warranted. Consequently, until these data are available any neurostimulation device should only be used in patients with medically intractable syndromes from tertiary headache centers either as part of a valid study or have shown to be effective in such controlled studies with an acceptable side effect profile.

Emerging treatment for chronic migraine and refractory chronic migraine

Introduction: Chronic migraine (CM), the suffering of 15 or more headache days with at least 8 of these migraine days, afflicts 1.3% - 5.1% of the global population. CM is the most common disorder faced by experts in tertiary headache centers. When resistant to conventional medical treatment and prophylactic medication this condition is known as refractory chronic migraine (RCM). RCM is one of the greatest challenges in headache medicine. Areas covered: State-of-the-art and future medical treatments of chronic migraine include: OnabotulinumtoxinA, antiepileptic drugs (Levetiracetam, Magnesium valproate hydrate, Lacosamide, BGG-492), 5-HT agonists (Lasmiditan, NXN-188, novel delivery systems of Sumatriptan, a well-established drug treatment for acute migraine), CGRP receptor antagonists (BMS-927711), ML-1 agonists (Ramelteon), orexin receptor antagonist (MK-6096), plant-derived compound (LLL-2011) and other multitarget drugs such as Tezampanel, Tonabersat, intranasal carbon dioxide and BOL-148. The role for neuromodulation, the application of targeted electrical stimulation, will be examined. Expert opinion: Medication overuse headache (MOH) is now recognized to be a major factor in many cases of both chronic and refractory chronic migraine. MOH must be addressed prior to evaluating the effectiveness of new preventative and prophylactic treatment approaches. Innovative new drugs and electrical neuromodulation are promising CM treatments. Future studies must carefully screen patients and acquire data that can lead to personalized, tailored treatment strategies.

A six year retrospective review of occipital nerve stimulation practice - controversies and challenges of an emerging technique for treating refractory headache syndromes

BackgroundA retrospective review of patients treated with Occipital Nerve Stimulation (ONS) at two large tertiary referral centres has been audited in order to optimise future treatment pathways.MethodsPatient’s medical records were retrospectively reviewed, and each patient was contacted by a trained headache expert to confirm clinical diagnosis and system efficacy. Results were compared to reported outcomes in current literature on ONS for primary headaches.ResultsTwenty-five patients underwent a trial of ONS between January 2007 and December 2012, and 23 patients went on to have permanent implantation of ONS. All 23 patients reached one-year follow/up, and 14 of them (61%) exceeded two years of follow-up. Seventeen of the 23 had refractory chronic migraine (rCM), and 3 refractory occipital neuralgia (ON). 11 of the 19 rCM patients had been referred with an incorrect headache diagnosis. Nine of the rCM patients (53%) reported 50% or more reduction in headache pain intensity and or frequency at long term follow-up (11–77 months). All 3 ON patients reported more than 50% reduction in pain intensity and/or frequency at 28–31 months. Ten (43%) subjects underwent surgical revision after an average of 11 ± 7 months from permanent implantation - in 90% of cases due to lead problems. Seven patients attended a specifically designed, multi-disciplinary, two-week pre-implant programme and showed improved scores across all measured psychological and functional parameters independent of response to subsequent ONS.ConclusionsOur retrospective review: 1) confirms the long-term ONS success rate in refractory chronic headaches, consistent with previously published studies; 2) suggests that some headaches types may respond better to ONS than others (ON vs CM); 3) calls into question the role of trial stimulation in ONS; 4) confirms the high rate of complications related to the equipment not originally designed for ONS; 5) emphasises the need for specialist multidisciplinary care in these patients.

The Use of 10‐Kilohertz Spinal Cord Stimulation in a Cohort of Patients With Chronic Neuropathic Limb Pain Refractory to Medical Management

It is the purpose of this study to document our experience with the use of a 10‐kHz high‐frequency spinal cord stimulation (SCS) device for the relief of neuropathic pain of the upper and lower limbs.

Subcutaneous botulinum toxin for chronic post-thoracotomy pain.

Objective:  Botulinum toxin is a neurotoxin that has been widely used in chronic pain for the treatment of multiple conditions with a component of localized muscle spasm. Recent studies suggest that botulinum toxin is effective in the treatment of neuropathic pain syndromes such as post‐herpetic neuralgia.

Does local anesthetic dilution influence the clinical effectiveness of multiple-injection axillary brachial plexus block?: a prospective, double-blind, randomized clinical trial in patients undergoing upper limb surgery.

Objectives: The relationship between the dose, volume, and concentration of local anesthetic and the quality and success of regional anesthesia remains unclear. Our aim was to test whether using 3 different volumes of the same local anesthetic dose influences the success rate of an axillary brachial plexus block with a multiple-injection technique in patients undergoing upper limb surgery. Methods: One hundred sixty-five patients were prospectively randomized to 1 of 3 groups. Each group received an axillary block with mepivacaine 400 mg, diluted in 3 different volumes (20, 30, and 40 mL). Outcome measures recorded were the block success rate at 30 mins, sensory and motor onset times, and length of postoperative sensory and motor blockade. Results: No difference was found in the rate of successful axillary plexus blocks determined when the 30-min follow-up ended among the 3 groups: 94% for 20-mL volume, 94% for 30-mL volume, and 98% for 40-mL volume. The median sensory and motor onset times of anesthesia did not differ. However, postoperative motor blockade and sensory analgesia lasted significantly longer in the patients receiving mepivacaine 400 mg diluted in a volume of 30 mL than in the other groups. Conclusions: An axillary brachial plexus block induced with a multiple-injection technique with mepivacaine 400 mg yields a high success rate regardless of the volume of anesthetic injected.

Can an Intrathecal, Catheter-tip-associated Inflammatory Mass Reoccur?

ObjectivesIntrathecal granuloma associated to the tip of catheters implanted in patients receiving long-term spinal infusion to alleviate chronic pain is a rare but potentially catastrophic complication. Its formation seems to be related to the intrathecal administration of opioid drugs, although not all opioids induce granuloma formation with the same frequency. MethodsIn this clinical report, we describe an intrathecal granuloma that reoccur twice in the same patient after its surgical removal. Results and DiscussionThis case report highlights the incomplete knowledge about the mechanism of granuloma formation and discuss the alternatives in the management of catheter-tip granulomas. This is the first case report of a patient in whom an intrathecal granuloma reoccurred twice after initial surgical removal. We also present and discuss a potential management strategy to avoid further surgery and resume intrathecal therapy early.

Changes in cerebrospinal fluid magnesium levels in patients undergoing spinal anaesthesia for hip arthroplasty: does intravenous infusion of magnesium sulphate make any difference? A prospective, randomized, controlled study

BACKGROUND Most investigators have attributed the reduced postoperative pain or anaesthetic drug requirements in patients receiving i.v. magnesium sulphate (MgSO(4)) infusion during spinal or general anaesthesia to central N-methyl-d-aspartate (NMDA) receptor magnesium (Mg) activity. In this study, we investigated how cerebrospinal fluid (CSF) Mg concentrations change after spinal anaesthesia, and whether peripherally infusing MgSO(4) influences central Mg levels. METHODS Forty-five patients undergoing continuous spinal anaesthesia for hip arthroplasty were randomly assigned to receive either i.v. MgSO(4) at a dose of 50 mg kg(-1) diluted in 100 ml 0.9% saline solution followed by 15 mg kg(-1) h(-1) for 6 h or saline at the same volume [mean (sd) 64 (10) ml]. The changes in CSF and serum total and ionized Mg concentrations were assessed at six time points before and after spinal anaesthesia. Secondary outcome variables included serum and CSF electrolytes and proteins. RESULTS Thirty-five patients completed the study. We found that spinal anaesthesia reduced total and ionized Mg concentrations in CSF by about 10%. Increasing serum Mg concentration over 80% of the baseline value left CSF Mg levels unchanged. CONCLUSIONS Spinal anaesthesia unexpectedly reduced CSF total and ionized Mg concentrations in patients undergoing hip arthroplasty, although the mechanism is unclear. The dose used for peripheral MgSO(4) infusion in this study had no influence on central Mg concentrations in neurologically healthy patients undergoing spinal anaesthesia. If CSF Mg concentration is a reliable marker of Mg brain bioavailability, peripherally infused MgSO(4) during spinal anaesthesia is unlikely to influence central NMDA receptor activity.

10 kHz High-Frequency Spinal Cord Stimulation for Chronic Axial Low Back Pain in Patients With No History of Spinal Surgery: A Preliminary, Prospective, Open Label and Proof-of-Concept Study.

To explore the effectiveness of 10 kHz high frequency spinal cord stimulation (HF10 therapy) treatment of chronic low back pain in patients who have not had spinal surgery.