Application status of electrical stimulation and repetitive transcranial magnetic stimulation in postherpetic neuralgia / 中华皮肤科杂志

For the treatment of postherpetic neuralgia, drugs have always played a major but unsatisfactory role. As auxiliary or alternative therapies for postherpetic neuralgia, non-pharmacological interventions, such as electrical stimulation and repetitive transcranial magnetic stimulation, not only have shown favorable efficacy, but also can decrease adverse reactions to drugs with high safety and patient acceptance, and are benificial for management of patients with postherpetic neuralgia.

Short-term spinal cord stimulation and pulsed radiofrequency for zoster-associated pain: an efficacy and safety comparisive study / 中华神经医学杂志

Objective:To compare the short-term and long-term efficacies and safety of short-term spinal cord stimulation (st-SCS) and pulsed radiofrequency (PRF) in treating zoster-associated pain (ZAP).Methods:A total of 208 ZAP patients who received treatment in Department of Pain Management, Provincial Hospital Affiliated to Shandong University from January 2019 to September 2021 were selected. They were divided into st-SCS group ( n=107) and PRF group ( n=101) according to different treatments. After differences of baseline data being balanced by 1∶1 propensity score matching between the two groups, scores of numerical rating scale (NRS), NRS remission rate, drug dosage, Pittsburgh Sleep Quality Index (PSQI) and complications of 86 patients from each 2 groups were compared and analyzed before surgery, 3 and 7 d after surgery, at discharge, and 1, 3, 6, 12 and 24 months after surgery. Results:NRS scores in st-SCS group and PRF group 3 and 7 d after surgery, at discharge, and 1, 3, 6, 12 and 24 months after surgery were significantly lower than those before surgery ( P<0.05). NRS scores in st-SCS group were significantly lower than those in PRF group at discharge and 1, 3, 6 and 12 months after surgery ( P<0.05). NRS remission rate in st-SCS group was significantly higher than that in PRF group at discharge and 1, 3, 6, 12 and 24 months after surgery, and total effective rate in st-SCS group was significantly higher than that in PRF group 1, 3, 6, and 12 months after surgery ( P<0.05). The pregabalin and gabapentin dosages in st-SCS group and PRF group 1, 3, 6, 12, and 24 months after surgery were significantly lower than those before surgery, and the gabapentin dosage in st-SCS group was significantly lower than that in PRF group 3 months after surgery ( P<0.05). PSQI in st-SCS group and PRF group at discharge and 6, 12 and 24 months after surgery was significantly decreased compared with that before surgery, and PSQI in st-SCS group at discharge and 6, 12 and 24 months after surgery was significantly decreased compared with that in PRF group ( P<0.05). No serious complications as spinal epidural hematoma or spinal nerve root and spinal cord injuries occurred in st-SCS group and PRF group. Conclusion:Both st-SCS and PRF can treat ZAP safely and effectively, but st-SCS has more advantages than PRF.

Anesthetic considerations in patients with implantable devices and chronic pain surgery / Consideraciones anestésicas en pacientes con dispositivos implantables y para cirugía de dolor crónico

Abstract The use of advanced invasive techniques for the control of chronic pain in patients with multiple comorbidities is becoming increasingly common. Neuromodulation offers a new management alternative involving the infusion of one or more drugs into the epidural or intrathecal space through a fully implantable infusion pump. It also involves spinal stimulation, a minimally invasive technique in which electrodes are positioned in the epidural space and connected to a pulse generator that is implanted subcutaneously and generates pulses designed to suppress the noxious stimulus. This article will describe the anesthetic considerations in cases of implantable drug delivery systems, and spinal and peripheral nerve stimulation devices. Additionally, patients with electrical or drug neuromodulation devices may present to anesthetic practice for surgical indications unrelated to their chronic pain pathology. Hence the importance of being familiar with the basic components of these devices, how they work, what drugs they use and the potential associated complications in the perioperative context, in order to ensure proper management and patient safety.

Resumen Cada vez es más común el empleo de técnicas invasivas avanzadas para el control del dolor crónico en paciente con múltiples comorbilidades. La neuro-modulación ofrece una nueva alternativa de manejo, que involucra la infusión de uno o más medicamentos en el espacio epidural o intratecal a través de una bomba de infusión totalmente implantable. También incluye la estimulación espinal, una técnica mínimamente invasiva que consiste en el posicionamiento de electrodos en el espacio epidural, conectados a un generador de pulso que se implanta subcutáneo y genera pulsos que buscan suprimir el estímulo nocivo. En este artículo se hará la descripción de las consideraciones anestésicas que se deben tener con sistemas de liberación de medicamentos implantables, dispositivos de estimulación medular y de nervio periférico. Adicionalmente, pueden aparecer pacientes portadores de dispositivos de neuromodulación eléctrica o medicamentosa que deben recibir anestesia para someterse a cirugía por razones diferentes a su patología de dolor crónico y deben conocerse sus implicaciones anestésicas. Por lo anterior, es importante conocer y estar familiarizados con los componentes básicos de dichos dispositivos: funcionamiento, medicamentos que utilizan y las potenciales complicaciones que se puedan tener con estos en el contexto perioperatorio, para garantizar un manejo adecuado y la seguridad del paciente.

Spinal cord stimulation in the management of neuropathic pain in cancer patients: case report / Neuroestimulación medular en el manejo del dolor neuropàtico en pacientes con cáncer: reporte de caso

Abstract Introduction Neuropathic pain is present in up to 40 % of all cancer patients. A considerable number of patients fail to achieve enough pain relief with conventional treatment, which is why therapeutic alternatives such as spinal cord stimulation should be considered. Case description and results This is the case of a female patient with chronic neuropathic pain secondary to a partial femoral nerve injury sustained during resection and lymph node dissection surgery with curative intent for a large stage II cell squamous cell carcinoma T2N0M0, localized in the right popliteal fossa. The patient presented with difficult to manage chronic neuropathic pain, despite receiving multiple oral analgesics and nerve blocks. A medullary neurostimulator was implanted that relieved the patient's pain intensity in up to 80%, in addition to improved function and quality of life. Conclusions Spinal cord stimulation is considered an effective neuromodulatory intervention which has shown satisfactory results in the treatment of various types of refractory chronic pain in cancer patients, including neuropathic pain.

Resumen Introducción El dolor neuropático está presente hasta en el 40 % de los pacientes con cáncer. Un número considerable de pacientes no logran un alivio suficiente del dolor con el tratamiento convencional, por lo cual deben considerarse alternativas terapéuticas como la estimulación de la médula espinal. Descripción del caso y resultados Caso de una paciente con dolor neuropático crónico secundario a lesión parcial de nervio femoral durante cirugía de resección y vaciamiento ganglionar con objetivos curativos de carcinoma escamocelular de célula grande T2N0M0 estadio II, localizado en la fosa poplítea derecha, quien cursó con dolor neuropático crónico de difícil manejo a pesar de recibir múltiples analgésicos orales y bloqueos nerviosos. Se implantó un neuroestimulador medular con lo cual se logró un alivio hasta del 80 % en intensidad de dolor de la paciente, además de una mejoría de su funcionalidad y calidad de vida. Conclusiones La estimulación de la médula espinal se considera una intervención neuromoduladora eficaz, que ha demostrado resultados satisfactorios para tratar diversas formas de dolor crónico refractario en los pacientes con cáncer, incluido el dolor neuropático.

Recent advance in epidural spinal cord electrical stimulation in dyskinesia after spinal cord injury / 中华神经医学杂志

Spinal cord injury (SCI) causes complete or incomplete loss of motor function, which affects patients' normal life. After electrode implantation, epidural spinal cord electrical stimulation (SCS) with optimal frequency, pulse width and intensity, combined with rehabilitation training, is able to promote the recovery of volitional control of motor activities, standing and stepping. Here, the progress of therapeutic effect of epidural spinal cord stimulation on the recovery of motor function in patients with spinal cord injury ware summarized to provide reference for its clinical application in the recovery of motor function after spinal cord injury.

Simulation study of spinal cord stimulation evoked compound action potential / 生物医学工程学杂志

Spinal cord stimulation (SCS) for pain is usually implanted as an open loop system using unchanged parameters. To avoid the under and over stimulation caused by lead migration, evoked compound action potentials (ECAP) is used as feedback signal to change the stimulating parameters. This study established a simulation model of ECAP recording to investigate the relationship between ECAP component and dorsal column (DC) fiber recruitment. Finite element model of SCS and multi-compartment model of sensory fiber were coupled to calculate the single fiber action potential (SFAP) caused by single fiber in different spinal cord regions. The synthetized ECAP, superimposition of SFAP, could be considered as an index of DC fiber excitation degree, because the position of crests and amplitude of ECAP corresponds to different fiber diameters. When 10% or less DC fibers were excited, the crests corresponded to fibers with large diameters. When 20% or more DC fibers were excited, ECAP showed a slow conduction crest, which corresponded to fibers with small diameters. The amplitude of this slow conduction crest increased as the stimulating intensity increased while the amplitude of the fast conduction crest almost remained unchanged. Therefore, the simulated ECAP signal in this paper could be used to evaluate the degree of excitation of DC fibers. This SCS-ECAP model may provide theoretical basis for future clinical application of close loop SCS base on ECAP.

Spinal Cord Stimulation as a Treatment Option for Refractory Chemotherapy-Induced Peripheral Neuropathy: Case Report

Colorectal cancer is one of the most common oncological diseases. Chemotherapy is usually recommended as an adjuvant treatment for stage-II, -III, and -IV tumors. Approximately 10% of the patients develop neuropathic pain after chemotherapy, and they may remain refractory despite the administration of drugs that are commonly used to treat neuropathic pain. Spinal cord stimulation is a good treatment option for neuropathic pain of the lower limbs, and it should be trialed in patients with chemotherapy-induced peripheral neuropathy. We report the case of a patient with oxaliplatin-induced neuropathy and neuropathic pain refractory to oral medication who was successfully treated by spinal cord stimulation.

Effectiveness of temporary spinal cord stimulation in herpetic neuralgia / 中华神经医学杂志

Objective:To evaluate the clinical outcomes of temporary spinal cord stimulation (SCS) in treatment of herpetic neuralgia.Methods:Patients with diagnosed herpetic neuralgia at acute or subacute periods received SCS in our hospital from January 2017 to January 2019. Changes of drug dosage, changes of pain and sleep, sequelae, and complications were recorded before and 7, 30 and 90 d after treatment.Results:(1) Thirty d after surgery, more than 50% patients stopped using the drugs; 90 d after surgery, 75.2% patients ( n=82) stopped using the drugs; 24.8% of the patients ( n=27) still had pain episodes and needed medication, but the dosage was less than before. (2) Visual analogue scale (VAS) scores and simple sleep quality scale scores decreased gradually with the extension of time, and these scores 7, 30 and 90 d after treatment were statistically different as compared with those before treatment ( P<0.05). (3) On the 90 th d of follow-up, 24.8% patients ( n=27) developed post-herpetic neuralgia, with VAS scores ranging from 4 to 6, and without affecting their daily life and sleep; none of the patients had serious complications. Conclusion:Temporary SCS is an effective way to relieve pain, and it can also reduce the incidence of post-herpetic neuralgia.

Advance in Spinal Cord Stimulation for Neuropathic Pain (review) / 中国康复理论与实践

Spinal cord stimulation (SCS) can inhibit or alleviate pain by blocking pain signal transmission, interfering with pain pathway, activating opioid pathway, stimulating locus coeruleus system and regulating γ-aminobutyric acid ergic. It is applied in the treatment of neuropathic pain (NP), such as post-herpetic neuralgia, failed back surgery syndrome, phantom limb pain, painful diabetic neuropathy, head and facial neuropathic pain, pudendal neuralgia, etc.

Successful Treatment with a Combination of Spinal Cord Stimulation and Physical Therapy for Complex Regional Pain Syndrome：A Case Report / The Japanese Journal of Rehabilitation Medicine

Spinal cord stimulation (SCS) has been reported to be effective for complex regional pain syndrome (CRPS). This is a case report of a patient with CRPS who was successfully treated with a combination of temporary SCS lead placement and physical therapy. A 19-year-old man presented with severe pain for a few months since receiving plaster cast fixation as treatment for an ankle sprain injury at the previous hospital. At his first visit to our pain center, he could not walk without crutches because of severe pain accompanied by symptoms such as allodynia, decreased skin temperature, redness, edema, muscle weakness, and changes in the appearance of the affected area. The symptoms met the diagnostic criteria for CRPS. Temporary SCS lead placement was performed to alleviate the pain and peripheral circulatory disorder, along with physiotherapy to improve the flexibility and restore the normal appearance of the affected limb. The interdisciplinary treatment effectively improved our patient's leg edema and walking ability, which consequently led to pain relief.

Successful Treatment with a Combination of Spinal Cord Stimulation and Physical Therapy for Complex Regional Pain Syndrome：A Case Report / The Japanese Journal of Rehabilitation Medicine

Spinal cord stimulation (SCS) has been reported to be effective for complex regional pain syndrome (CRPS). This is a case report of a patient with CRPS who was successfully treated with a combination of temporary SCS lead placement and physical therapy. A 19-year-old man presented with severe pain for a few months since receiving plaster cast fixation as treatment for an ankle sprain injury at the previous hospital. At his first visit to our pain center, he could not walk without crutches because of severe pain accompanied by symptoms such as allodynia, decreased skin temperature, redness, edema, muscle weakness, and changes in the appearance of the affected area. The symptoms met the diagnostic criteria for CRPS. Temporary SCS lead placement was performed to alleviate the pain and peripheral circulatory disorder, along with physiotherapy to improve the flexibility and restore the normal appearance of the affected limb. The interdisciplinary treatment effectively improved our patient's leg edema and walking ability, which consequently led to pain relief.

Successful removal of permanent spinal cord stimulators in patients with complex regional pain syndrome after complete relief of pain

BACKGROUND: It is uncommon for patients who have received a permanent implant to remove the spinal cord stimulator (SCS) after discontinuation of medication in complex regional pain syndrome (CRPS) due to their completely painless state. This study evaluated CRPS patients who successfully removed their SCSs. METHODS: This 10-year retrospective study was performed on patients who had received the permanent implantation of an SCS and had removed it 6 months after discontinuation of stimulation, while halting all medications for neuropathic pain. Age, sex, duration of implantation, site and type of CRPS, and their return to work were compared between the removal and non-removal groups. RESULTS: Five (12.5%, M/F = 4/1) of 40 patients (M/F = 33/7) successfully removed the permanent implant. The mean age was younger in the removal group (27.2 ± 6.4 vs. 43.5 ± 10.7 years, P < 0.01). The mean duration of implantation in the removal group was 34.4 ± 18.2 months. Two of 15 patients (13.3%) and 3 of 25 patients (12%) who had upper and lower extremity pain, respectively, had removed the implant. The implants could be removed in 5 of 27 patients (18.5%) with CRPS type 1 (P < 0.01). All 5 patients (100%) who removed their SCS returned to work, while only 5 of 35 (14.3%) in the non-removal group did (P < 0.01). CONCLUSIONS: Even though this study had limited data, younger patients with CRPS type 1 could remove their SCSs within a 5-year period and return to work with complete pain relief.

Spinal Cord Stimulation for Pain Treatment After Spinal Cord Injury / 神经科学通报·英文版

In addition to restoration of bladder, bowel, and motor functions, alleviating the accompanying debilitating pain is equally important for improving the quality of life of patients with spinal cord injury (SCI). Currently, however, the treatment of chronic pain after SCI remains a largely unmet need. Electrical spinal cord stimulation (SCS) has been used to manage a variety of chronic pain conditions that are refractory to pharmacotherapy. Yet, its efficacy, benefit profiles, and mechanisms of action in SCI pain remain elusive, due to limited research, methodological weaknesses in previous clinical studies, and a lack of mechanistic exploration of SCS for SCI pain control. We aim to review recent studies and outline the therapeutic potential of different SCS paradigms for traumatic SCI pain. We begin with an overview of its manifestations, classification, potential underlying etiology, and current challenges for its treatment. The clinical evidence for using SCS in SCI pain is then reviewed. Finally, future perspectives of pre-clinical research and clinical study of SCS for SCI pain treatment are discussed.

Spinal cord stimulation and pulsed radiofrequency in treatment of herpes zoster neuralgia in the elderly / 中华神经医学杂志

Objective To investigate the efficacies and differences of spinal cord stimulation (SCS) and pulsed radiofrequency (PRF) in the treatment of herpes zoster neuralgia in the elderly. MethodsSixty-three patients with herpes zoster neuralgia over 50 years old, admitted to our hospital from January 2018 to January 2019, were divided into SCS group (n=31) and PRF group (n=32) by prospective, randomized and controlled study. The stimulating electrodes were placed in epidural spinal ganglion segment for two weeks after percutaneous puncture in SCS group. In the PRF group, the radiofrequency needles were percutaneously punctured to the dorsal root ganglion under the guidance of X-ray. After the location of contrast medium was confirmed, each target was treated by pulsed radiofrequency for 360 seconds, followed by anti-inflammatory compound liquid injection. Numeric Rating Scale (NRS) scores, effective rate (percentage of patients having pain relief>50％) and signficant differences were noted between the two group at each time point (P>0.05).The effective rates of pain treatment of patients from the two group reached to 56.67%-81.25%,and there was no significant difference between the two groups at each time point (P>0.05).The complete pain relief rate reached to 37%-71% in the two groups,and there was no significant difference between the two groups at each time point (P>0.05).Number of patients used analgesics and calcium channel antagonists before and after operation in the two groups showed significant differences (χ2=20.917,P=0.000; χ2=18.273,P=0.000),and number of patients used analgesics and calcium channel antagonists 4,12 and 24 weeks after operation in the two groups was significantly smaller than that before operation (P<0.05); but,there were no significant differences between the two groups at each time point (P>0.05).Conclusion SCS and PFR can effectively treat herpes zoster neuralgia and reduce the incidence of sequelae,without no significant difference in the clinical efficacy.

Changes of RAAS in atrial fibrillation model dogs after spinal cord stimulation and its inhibitory effect on atrial fibrillation / 吉林大学学报(医学版)

Objective: To investigate the changes of the serum indexes of renin-angiotensin-aldosterone system (RAAS) and atrial fibrillation burden in the atrial fibrillation model dogs underwent spinal cord stimulation (SCS) therapy, and to illuminate the therapeutic effect of SCS on the atrial fibrillation and its effect on RAAS Methods: A total of 24 healthy adult dogs were chosen The pacemakers and miniaturized insertable cardiac monitors were implanted into 16 dogs to establish the atrial fibrillation models by rapid right atrial pacing. Then 16 model dogs were divided into atrial fibrillation (AF) group and SCS group (n=8). The spinal cord stimulators were implanted into the dogs in SCS group to release stimulation for 12 weeks. And the rest dogs were regareded as blank control group (n=8). The atrial fibrillation burden of dogs in AF group and SCS group was monitored by miniaturized insertable cardiac monitors; the left and right atrial areas of dogs in three groups were measured by echocardiography; the serum levels of renin, angiotensin E (Ang E), aldosterone (ALD), angiotensin E type 1 receptor (AT1R), angiotensin E type 2 receptor (AT2R) and angiotensin converting enzyme 2 (ACE2) of the dogs in three groups were detected by ELISA method. Results: Compared with AF group, the atrial fibrillation burden of the dogs in SCS group was decresed obviously (P0. 05); the left and right atrial areas of the dogs in SCS group were larger than those in blank control group (P<0. 05). The serum ACE2 level of dogs in AF group was lower than that in blank control group (P<0. 05) and the levels of serum renin, Ang E, ALD, AT1R and AT2R of the dogs in AF group were all higher than those in blank control group (P<0. 05); the serum ACE2 level of the dogs in SCS group was higher than that in AF group (P<0. 05) and the levels of serum renin, Ang E, ALD, AT1R, and AT2R of the dogs in SCS group were all lower than those in AF group (P<0. 05). Compared with before modeling, the serum ACE2 level of dogs in AF group after modeling was decresed (P<0. 05), and the levels of serum renin, Ang E, ALD, AT1R, and AT2R were incresed (P<0. 05); compared with before treatment, the serum ACE2 level of the dogs in SCS group after treatment was incresed (P<0. 05), and the levels of serum renin, Ang E, ALD, AT1R, and AT2R were decresed (P<0.05). Conclusion: Atrial fibrillation can activate the RAAS. SCS therapy can suppress the atrial fibrillation and it can suppress RAAS activated by atrial fibrillation, so SCS can restraint the deterioration of atrial fibrillation. The serum RAAS indexes are so important observation indexes to evaluate the outcome of SCS in the treatment of atrial fibrillation.

Spinal cord stimulation for fail back surgery syndrome: literature review and clinical study / Estimulación de la médula espinal para el síndrome de cirugía de espalda fallida: revisión de la literatura y estudio clínico / Estimulação da medula espinhal para síndrome de cirurgia de retorno: revisão da literatura e estudo clínico

ABSTRACT Objective: Fail back surgery syndrome (FBSS) is a common cause of pain following spine surgery, and is associated with persistent or recurrent pain despite anatomically correct intervention. Spinal cord stimulation (SCS) is regarded as one of the most effective methods of treatment for fail back surgery syndrome. Methods: We studied 34 patients who underwent test stimulation and chronic SCS for FBSS. Results: Six months postoperatively, mean improvement by the visual analog scale (VAS) of average and maximum daily pain, and the painDETECT score, were 54.4%, 50.7% and 57.3%, respectively. This meets the criteria for effectiveness of the method, according to the literature. Most of patients reported significant improvements in life quality and less need for analgesics. Complications were seen in nine patients (26.4%) and included: intraoperative dura injury (one patient, 2.9%), wound infection (one patient, 2.9%), and electrode displacement (seven patients, 20.5%). No cases of postoperative neurological deterioration were seen. Conclusions: SCS is safe and effective for the treatment of neuropathic pain caused by FBSS. Level of Evidence IV; Case series.

RESUMO Objetivos: A síndrome da cirurgia de falência reversa (SAF) é uma causa comum de dor após cirurgia de coluna e associada a dor persistente ou recorrente, apesar da intervenção anatomicamente correta. Estimulação da medula espinhal (SCS) é considerado como um dos métodos mais eficazes de tratamento para a síndrome de cirurgia de retorno. Métodos: Foram estudados 34 pacientes submetidos a estimulação de teste e SCS crônica para FBSS. Resultados: 6 meses de pós-operatório melhora a média de dor diária média e máxima diária na escala análoga visual (VAS), bem como a pontuação do PainDetect foram de 54,4%, 50,7% e 57,3%, respectivamente. Ele atende aos critérios de eficácia do método, de acordo com a literatura. A maioria dos pacientes relatou melhora significativa da qualidade de vida e menor necessidade de analgésicos. As complicações foram observadas em nove pacientes (26,4%) e incluíram: lesão da dura-máter intraoperatória (um paciente, 2,9%), infecção da ferida (um paciente, 2,9%), deslocamento do eletrodo (sete pacientes, 20,5%). Não houve casos de deterioração neurológica no pós-operatório. Conclusões: A SCS é segura e eficaz para o tratamento da dor neuropática causada pela FBSS. Nível de Evidência IV; Séries de casos.

RESUMEN Objetivo: El síndrome de cirugía de espalda fallida (FBSS) es una razón común para el dolor después de la cirugía de la columna vertebral y se asocia con dolor persistente o recurrente a pesar de la intervención anatómicamente correcta. La estimulación de la médula espinal (SCS) se considera uno de los métodos de tratamiento más eficaces para el síndrome de cirugía de espalda fallida. Métodos: Se estudiaron 34 pacientes que se sometieron a estimulación de prueba y SCS crónica para FBSS. Resultados: A los seis meses la mejora promedio postoperatoria por la escala visual análoga (EVA) del dolor diario promedio y máximo diario, así como el puntaje de painDETECT fueron 54,4%, 50,7% y 57,3%, respectivamente. Esto cumple con los criterios de efectividad del método, según la literatura. La mayoría de los pacientes informaron una mejoría significativa de la calidad de vida y una menor necesidad de analgésicos. Las complicaciones se observaron en nueve pacientes (26,4%) e incluyeron: lesión duramadre intraoperatoria (uno paciente, 2,9%), infección de la herida (uno paciente, 2,9%), desplazamiento del electrodo (siete pacientes, 20,5%). No se observaron casos de deterioro neurológico postoperatorio. Conclusiones: SCS es seguro y efectivo para el tratamiento del dolor neuropático causado por FBSS. Nivel de Evidencia IV; Series de casos.

Spinal Cord Stimulation Frequency Influences the Hemodynamic Response in Patients with Disorders of Consciousness / 神经科学通报·英文版

Spinal cord stimulation (SCS) is a promising technique for treating disorders of consciousness (DOCs). However, differences in the spatio-temporal responsiveness of the brain under varied SCS parameters remain unclear. In this pilot study, functional near-infrared spectroscopy was used to measure the hemodynamic responses of 10 DOC patients to different SCS frequencies (5 Hz, 10 Hz, 50 Hz, 70 Hz, and 100 Hz). In the prefrontal cortex, a key area in consciousness circuits, we found significantly increased hemodynamic responses at 70 Hz and 100 Hz, and significantly different hemodynamic responses between 50 Hz and 70 Hz/100 Hz. In addition, the functional connectivity between prefrontal and occipital areas was significantly improved with SCS at 70 Hz. These results demonstrated that SCS modulates the hemodynamic responses and long-range connectivity in a frequency-specific manner (with 70 Hz apparently better), perhaps by improving the cerebral blood volume and information transmission through the reticular formation-thalamus-cortex pathway.

Current Status of Neuromodulatory Therapies for Disorders of Consciousness / 神经科学通报·英文版

Treatment for disorders of consciousness (DOCs) is still a Gordian knot. Evidence-based guidelines on the treatment of DOC patients are not currently available, while neuromodulation techniques are seen as a potential treatment. Multiple neuromodulation therapies have been applied. This article reviews the most relevant studies in the literature in order to describe a clear picture of the current state of neuromodulation therapies that could be used to treat DOC patients. Both invasive and non-invasive brain stimulation is discussed. Significant behavioral improvements in prolonged DOCs under neuromodulation therapies are rare. The efficacy of various such therapies remains a matter of debate. Further clinical investigations of existing techniques in larger samples properly controlling for spontaneous recovery are needed, and new approaches are awaited.

Failed Back Surgery Syndrome: A Review Article

Postsurgical spine syndrome is becoming an increasingly common challenge for clinicians who deal with spinal disorders owing to the expanding indications for spinal surgery and the aging world population. A multidisciplinary approach is most appropriate for patients who are unlikely to benefit from further formal surgical intervention. Anticonvulsant medications are effective in managing neuropathic pain after surgery, whereas opioids are rarely beneficial. Neuromodulation via a surgically implanted dorsal column neurostimulator is gaining popularity owing to its substantial superiority over conventional medical management and/or further surgical intervention. However, considering that prevention is always better than cure, spinal surgeons need to be well aware of the many poor prognostic indicators for spinal surgery, particularly psychosocial overlay.

Neuromonitoring for Spinal Cord Stimulation Lead Placement Under General Anesthesia

Spinal cord stimulation (SCS) is a common therapeutic technique for treating medically refractory neuropathic back and other limb pain syndromes. SCS has historically been performed using a sedative anesthetic technique where the patient is awakened at various times during a surgical procedure to evaluate the location of the stimulator lead. This technique has potential complications, and thus other methods that allow the use of a general anesthetic have been developed. There are two primary methods for placing leads under general anesthesia, based on 1) compound muscle action potentials and 2) collisions between somatosensory evoked potentials. Both techniques are discussed, and the literature on SCS lead placement under general anesthesia using intraoperative neurophysiological mapping is comprehensively reviewed.