Effect of Scalp Nerve Block with Ropivacaine on Postoperative Pain in Patients Undergoing Craniotomy: A Randomized, Double Blinded Study.

Scalp nerve block with ropivacaine has been shown to provide perioperative analgesia. However, the best concentration of ropivacaine is still unknown for optimal analgesic effects. We performed a prospective study to evaluate the effects of scalp nerve block with varied concentration of ropivacaine on postoperative pain and intraoperative hemodynamic variables in patients undergoing craniotomy under general anesthesia. Eighty-five patients were randomly assigned to receive scalp block with either 0.2% ropivacaine, 0.33% ropivacaine, 0.5% ropivacaine, or normal saline. Intraoperative hemodynamics and post-operative pain scores at 2, 4, 6, 24 hours postoperatively were recorded. We found that scalp blockage with 0.2% and 0.33% ropivacaine provided adequate postoperative pain relief up to 2 h, while administration of 0.5% ropivacaine had a longer duration of action (up to 4 hour after craniotomy). Scalp nerve block with varied concentration of ropivacaine blunted the increase of mean arterial pressure in response to noxious stimuli during incision, drilling, and sawing skull bone. 0.2% and 0.5% ropivacaine decreased heart rate response to incision and drilling. We concluded that scalp block using 0.5% ropivacaine obtain preferable postoperative analgesia compared to lower concentrations. And scalp block with ropivacaine also reduced hemodynamic fluctuations in craniotomy operations.

A comparison of effects of scalp nerve block and local anesthetic infiltration on inflammatory response, hemodynamic response, and postoperative pain in patients undergoing craniotomy for cerebral aneurysms: a randomized controlled trial.

BACKGROUND: The purpose of this study was to compare the effects of scalp nerve block (SNB) and local anesthetic infiltration (LA) with 0.75% ropivacaine on postoperative inflammatory response, intraoperative hemodynamic response, and postoperative pain control in patients undergoing craniotomy. METHODS: Fifty-seven patients were admitted for elective craniotomy for surgical clipping of a cerebral aneurysm. They were randomly divided into three groups: Group S (SNB with 15 mL of 0.75% ropivacaine), group I (LA with 15 mL of 0.75% ropivacaine) and group C (that only received routine intravenous analgesia). Pro-inflammatory cytokine levels in plasma for 72 h postoperatively, hemodynamic response to skin incision, and postoperative pain intensity were measured. RESULTS: The SNB with 0.75% ropivacaine not only decreased IL-6 levels in plasma 6 h after craniotomy but also decreased plasma CRP levels and increased plasma IL-10 levels 12 and 24 h after surgery compared to LA and routine analgesia. There were significant increases in mean arterial pressure 2 and 5 mins after the incision and during dura opening in Groups I and C compared with Group S. Group S had lower postoperative pain intensity, longer duration before the first dose of oxycodone, less consumption of oxycodone and lower incidence of PONV through 48 h postoperatively than Groups I and C. CONCLUSION: Preoperative SNB attenuated inflammatory response to craniotomy for cerebral aneurysms, blunted the hemodynamic response to scalp incision, and controlled postoperative pain better than LA or routine analgesia. TRIAL REGISTRATION: Clinicaltrials.gov NCT03073889 (PI:Xi Yang; date of registration:08/03/2017).

Scalp acupuncture treatment for children's autism spectrum disorders: A systematic review and meta-analysis.

BACKGROUND: Autism spectrum disorder (ASD) is a neurodevelopment disorder without definitive cure. Previous studies have provided evidences for efficacy and safety of scalp acupuncture in children with ASD. However, the efficacy of scalp acupuncture treatment (SAT) in children with ASD has not been evaluated systematically. The objective of this study is to evaluate the efficacy of SAT in children with ASD. METHODS: Information from 6 databases, including MEDLINE, EMBASE, Cochrane database, AMED, China National Knowledge Infrastructure, and Wanfang Data, were retrieved from the inception of each database from 1980 through September 2018. Randomized controlled trials evaluating the efficacy of SAT for patients with ASD were included. The primary outcome measures were the Childhood Autism Rating Scale (CARS) and Autism Behavior Checklist (ABC). The secondary outcome measures were Psychoeducational Profile (Third Edition) (PEP-3) scores. Risk of bias assessment and data synthesis were conducted with Review Manager 5.3 software. Methodological quality was assessed with the Cochrane risk of bias tool. RESULTS: Fourteen trials with 968 participants were conducted and 11 of the trials were suitable for meta-analysis. Compared with behavioral and educational interventions, SAT significantly decreased the overall CARS scores for children under 3 years old (mean difference (MD) = 3.08, 95% confidence interval (CI) [-3.96, -2.19], P < .001) and above 3 years old (MD = 5.29, 95% CI [-8.53, -2.06], P < .001), ABC scores (MD = 4.70, 95% CI [-6.94, -2.79], P < .001). Furthermore, SAT significantly improved PEP-3 scores in communication (MD = 3.61, 95% CI [2.85, 4.37], P < .001), physical ability (MD = 2.00, 95% CI [1.16, 2.84], P < .001), and behavior (MD = 2.76, 95% CI [1.80, 2.71], P < .001). CONCLUSION: SAT may be an effective treatment for children with ASD. Given the heterogeneity and number of participants, randomized controlled trials of high quality and design are required before widespread application of this therapy.

Which one is more effective for analgesia in infratentorial craniotomy? The scalp block or local anesthetic infiltration.

OBJECTIVES: The most painful stages of craniotomy are the placement of the pin head holder and the skin incision. The primary aim of the present study is to compare the effects of the scalp block and the local anesthetic infiltration with bupivacaine 0.5% on the hemodynamic response during the pin head holder application and the skin incision in infratentorial craniotomies. The secondary aims are the effects on pain scores and morphine consumption during the postoperative 24h. METHODS: This prospective, randomized and placebo controlled study included forty seven patients (ASA I, II and III). The scalp block was performed in the Group S, the local anesthetic infiltration was performed in the Group I and the control group (Group C) only received remifentanil as an analgesic during the intraoperative period. The hemodynamic response to the pin head holder application and the skin incision, as well as postoperative pain intensity, cumulative morphine consumption and opioid related side effects were compared. RESULTS: The scalp block reduced the hemodynamic response to the pin head holder application and the skin incision in infratentorial craniotomies. The local anesthetic infiltration reduced the hemodynamic response to the skin incision. As well as both scalp block and local anesthetic infiltration reduced the cumulative morphine consumption in postoperative 24h. Moreover, the pain intensity was lower after scalp block in the early postoperative period. CONCLUSION: The scalp block may provide better analgesia in infratentorial craniotomies than local anesthetic infiltration.

Essential regional nerve blocks for the dermatologist: part 1.

The aim of this two-part series is to provide an up-to-date review of essential regional nerve blocks for dermatological practice. In Part 1, we give a concise overview of local anaesthetics and their potential complications, as well as the relevant anatomy and cutaneous innervation of the face and scalp. This culminates in a step-by-step practical guide to performing each nerve block.

Feasibility of combined epicranial temporal and occipital neurostimulation: treatment of a challenging case of headache.

BACKGROUND: Evidence of a paradigm shift towards epicranial neurostimulation treatment techniques aimed at the site of headache pain is beginning to populate the literature. This is most apparent by 2 recently published reports describing alternative approaches to peripheral nerve stimulation techniques for refractory migraine, including hemiplegic migraine. OBJECTIVES: To contribute to the emerging literature on epicranial-based neuroaugmentative approaches which target site-specific areas of distinct, but relatively diffuse, headache pain. Specifically, we describe the feasibility of a novel neurostimulation technique: occipital nerve stimulation, combined with bilateral subcutaneous electrical stimulation over the temporal region, to treat a patient dually diagnosed with "complicated migraine" and occipital neuralgia. Integral to this report, key stimulation programming data are also presented to better distinguish the role of this form of therapy in migraine, or other headache forms, from both the clinical and biomedical perspectives. METHODS: Case presentation with literature review. RESULTS: At 24-month follow-up, headache onset had been reduced by more than 50%, including cessation of neurologic deficits that accompanied the patient's migraines. No complications or adverse side effects are reported. The programming data reported here supports a proposed mechanism of action concerning stimulation of the auriculotemporal nerve distribution/anterior temporal region for management of refractory pain in migraine. LIMITATIONS: Case presentation provides only initial assessment of treatment safety, not conclusive evidence of treatment effectiveness. Future studies which consider "follow-the-path" epicranial approaches to peripheral nerve stimulation techniques for refractory headache pain are needed to better quantify outcomes and mechanisms of action. CONCLUSIONS: In the single case reported here, the feasibility of a novel neurostimulation technique (occipital nerve stimulation/bilateral subcutaneous temporal region stimulation) to treat headache is presented. At the 24-month follow-up, no complications (such as loss of coverage due to lead displacement or lead fracture or erosion) or adverse side effects were reported. Finally, inclusion of fundamental programming data in reports on neuroaugmentative approaches to headache care will complement initiatives in research from the clinical and biomedical communities involved in this field.

[Subcutaneous peripheral stimulation of the greater occipital nerve for the treatment of chronic headache syndromes]. / Subkutane periphere Stimulation des N. occipitalis major zur Behandlung chronischer Kopfschmerzsyndrome.

Medical treatment for certain chronic headache syndromes such as hemicrania continua (HC), chronic migraine (CM) or chronic cluster headache (CCH) is challenging and in many cases does not lead to sufficient pain relief or is limited by severe side effects. In the last few years neuromodulatory treatments such as subcutaneous stimulation of the greater occipital nerve or deep brain stimulation (DBS) in the hypothalamus have evolved. This report focuses on current knowledge and the results of peripheral subcutaneous nerve stimulation (SPNS) in the literature of the described headache syndromes and presents our own long-term results in ten patients. Technical details of implantation and possible complications are reported. The results between the two different stimulation types are compared. In summary, peripheral nerve stimulation of the greater occipital nerve is less invasive but also less effective in comparison to hypothalamic stimulation. However, the severity and frequency of pain attacks is significantly reduced. For other intractable headache syndromes SPNS of the greater occipital nerve offers a reasonable addition to medical treatment.

Occipital nerve stimulator lead pathway length changes with volunteer movement: an in vitro study.

BACKGROUND: Occipital nerve stimulation is a modality reserved for refractory headache disorders. Leads (wires) are inserted subcutaneously in the occipital region to stimulate the distal C1-3 nerves; lead migration may result from repeated mechanical forces on the lead associated with patient movement. The primary aim of this study was to determine implantation pathways associated with the least pathway length change secondary to body movement in an in vitro model of an occipital stimulator system. METHODS: After institutional review board approval, 10 volunteers were recruited. The expected pathway of an occipital stimulator system was identified and measured externally, and then changes in pathway length were measured during various volunteer movements, including neck and low back flexion, extension, rotation, and lateral flexion. The pathways studied included those that connect internal pulse generators in the gluteal, low abdominal, and infraclavicular regions to occipital leads inserted via a cervical or retromastoid approach. RESULTS: The flexion/extension pathway length changes associated with midline occipital and retromastoid sites to the infraclavicular site were significantly less than those pathways to the periscapular site. Also, the abdominal site was associated with less pathway length change during flexion/extension than the gluteal site. CONCLUSIONS: Internal pulse generators in sites other than the buttock, including infraclavicular or low abdomen, may be associated with lower lead migration risk. There are many considerations when selecting insertion sites and lead pathways for occipital nerve stimulation. Implanters and patients may consider these results when contemplating surgical approaches to this challenging form of peripheral nerve stimulation.

Occipital nerve stimulation (ONS). Surgical technique and prevention of late electrode migration.

Occipital nerve stimulation (ONS) is an emerging procedure for the treatment of cranio-facial pain syndromes and headaches refractory to conservative treatments. The aim of this report is to describe in detail the surgical intervention and to introduce some useful tricks that help to avoid late displacement and migration of the suboccipital leads. The careful description of the surgical steps may contribute to a standardization of the procedure and make the interpretation of results easier even if obtained in series of patients operated on by different authors.

Treatment of hemicrania continua by occipital nerve stimulation with a bion device: long-term follow-up of a crossover study.

BACKGROUND: Hemicrania continua (HC) is a primary headache that comprises persistent unilateral pain, is associated with cranial autonomic features, and is responsive to indometacin. Some patients are unable to tolerate this treatment or it is contraindicated; for these patients, the medical options for therapy are restricted. Occipital nerve stimulation (ONS) is an effective treatment for medically intractable primary headache, but only three cases of HC treated with ONS have been reported. Here, we report long-term safety and efficacy data for ONS in six patients with HC. ONS was provided by a unilateral neurostimulation device, known as a bion, which might be described as a second-generation ONS device. METHODS: Six patients aged 18 years or older who were diagnosed with HC had a suboccipital bion device implanted ipsilateral to their headache and received continuous unilateral ONS. A crossover study design was used: the bion was on for the first 3 months, off for the fourth month, and on again during long-term follow-up. Detailed prospective headache diaries were kept for 1 month before implantation and for 5 months afterwards. Long-term data were obtained from patients' estimates of their outcome. The outcome of this study was assessed by a comparison of headache pain severity before and after ONS. FINDINGS: At a median follow-up of 13.5 months (range 6-21 months), five of six patients reported sufficient benefit to recommend the device to other patients with HC. At long-term follow-up, four of six patients reported a substantial improvement (80-95%), one patient reported a 30% improvement, and one patient reported that his pain was worse by 20%. The onset of the benefit of ONS was delayed by days to weeks, and headaches did not recur for a similar period when the device was switched off. Adverse events were mild and associated with transient overstimulation. INTERPRETATION: ONS appears to be a safe and effective treatment for HC, particularly when indometacin is not tolerated or is contraindicated. The bion device was well tolerated, easily inserted without significant morbidity, and is one-twentieth of the volume of current devices. Such miniaturised devices are a potential new option for treatment of HC.

The role of the craniospinal nerves in mediating the antinociceptive effect of transcranial electrostimulation in the rat.

Transcranial electrostimulation (TES) has been reported to elicit significant analgesia, but its mechanism of action has not been elucidated. In a recently introduced clinically relevant rat model of TES we have validated and characterized the TES antinociceptive effect, suggesting involvement of the sensory nerves of the rat's scalp in mediating that effect. In this study, we have further investigated the role of the craniospinal nerves by attempting to block the TES antinociceptive effect with local anesthetic injected under the TES electrodes. We also applied different transcutaneous electrical nerve stimulation modalities through the TES electrodes and compared the elicited antinociceptive effect to that of TES. The antinociceptive effect was assessed by measuring nociceptive thresholds in the tail-flick latency test in awake, unrestrained male rats. Data were analyzed by one-way analysis of variance followed by the Bonferroni t-test. The TES antinociceptive effect was significantly reduced after local anesthetic injection, and administration of 100 Hz transcutaneous electrical nerve stimulation was, over time, capable of eliciting the same degree of antinociceptive effect as TES. We conclude that sensory craniospinal nerves play a critical role in mediating the TES antinociceptive action and offer a hypothesis on the underlying mechanism(s) responsible for this action.

High-resolution EEG: a new realistic geometry spline Laplacian estimation technique.

BACKGROUND: A new realistic geometry (RG) spline Laplacian estimation technique has been developed for high-resolution EEG imaging. METHODS: Estimation of the parameters associated with the spline Laplacian is formulated by seeking the general inverse of a transfer matrix. The number of spline parameters, which need to be determined through regularization, is reduced to one in the present approach, thus enabling easy implementation of the RG spline Laplacian estimator. RESULTS: Computer simulation studies have been conducted to test the feasibility of the new approach in a 3-concentric-sphere head model. The new technique has also been applied to human visual evoked potential data with a RG head model. CONCLUSIONS: The present numerical and experimental results demonstrate the feasibility of the new approach and indicate that the RG spline Laplacian can be estimated easily from the surface potentials and the scalp geometry.

Proximal receptors and the mechanical stimulation of the fingers: a somatosensory evoked potential study.

OBJECTIVE: To characterize scalp responses to mechanical stimulation of the fingers and evaluate the contribution of different receptors. DESIGN AND METHODS: Somatosensory evoked responses to mechanical stimulation of the right third finger were recorded from a P3-P4 montage (n = 15) and from a F3-P4 montage (n = 9) as well as after electrical stimulation (n = 9). Responses after mechanical stimulation of the distal region of the finger, with the hand at different positions, were also recorded (n = 8). Complementary experiments in a small number of individuals included EMG and accelerometer recordings as well as anaesthesia of the finger. RESULTS: Scalp responses characterized by an initial sequence of waves, here called NI-PI-NII, were recorded from the P3-P4 montage. Mean peak latencies were 20, 23 and 26 ms, respectively; electrical stimulation of the same region evoked an initial negativity (mean peak latency 23 ms). EMG recordings suggested the involvement of different receptors in response to electrical and mechanical stimulation. Accelerometer recordings showed the spread of a sizable mechanical wave at the forearm. Anaesthesia did not change the responses to mechanical stimulation. CONCLUSIONS: Relatively small mechanical stimuli applied at distal phalanxes may activate proximal receptors which generate scalp recorded responses that may completely occlude the contribution of the distal receptors.

P300: the similarities and differences in the scalp distribution of visual and auditory modality.

PURPOSE: To examine the topographic relationship of P3(00) between the visual and auditory modalities, especially to examine whether there are any modality-specific hemispheric differences of P3 in normal adults. METHODS: The P3s were recorded from the same 41 normal right-handed males between the ages of 20 and 33 in both a typical auditory oddball task and a visual oddball paradigm with novel stimuli, with an extensive set of 61 scalp electrodes. In addition to the visual comparison and quantitative assessment of current source density (CSD) maps between the two modalities, canonical correlation analyses on the P3 raw amplitudes and examination of interaction effects of modality x location on both raw and normalized P3 data were performed. RESULTS: The canonical correlation between modalities was generally high, especially at the left parietal brain region. There were no significant hemispheric effects in anterior brain but significant left-greater-than-right hemispheric effects in posterior brain regions in both modalities; modality-specific hemispheric effect was observed only at the parietal region. Strong surface current density activities were observed in the midline parietal-occipital area, and left and right boundary areas of temporal and inferior frontal region. CONCLUSIONS: The topographic similarities between P3s recorded in the visual and auditory modality outnumber the differences. Combining data from CSD assessments and profile analysis of P3 topography support the hypothesis of multiple generators of P3 that are differentially active in processing stimuli from different sensory modalities and are not symmetrically distributed between the two hemispheres.

The role of the human motor cortex in the control of complex and simple finger movement sequences.

We evaluated the effects of high-frequency repetitive transcranial magnetic stimulation (rTMS) over the primary motor cortex (M1) at different stimulus intensities on finger sequences of varying complexity. Eighteen subjects played unimanual finger sequences of different complexity on an electronic piano. For each finger sequence, 16 notes were played to the 2 Hz beat of a metronome. After the first four notes, rTMS was applied to the scalp location overlying the hand motor representation for approximately 2 s. Accuracy and timing errors were analysed. Stimulation over the M1 had a differential effect on sequences of different complexity. Stimulus intensities capable of disrupting the performance of a complex sequence did not affect simple sequences. To disrupt simple sequences, the stimulus strength had to be augmented. This effect was characteristic of the contralateral M1 position (five other scalp locations were also stimulated). It is argued that the differential effect of rTMS on simple and complex sequences is probably due to interference with M1 function. Interference with the lateral premotor cortex (PMC) may play an additional role. The particular relevance of the M1 is supported by results in a patient with PMC stroke. The present findings suggest that the human M1 plays a greater role in the performance of complex than of simple finger movement sequences. One possible explanation could be that the human M1 is not only an executive motor area but can also contribute to movement sequence organization.