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INTRODUCTION: Spinal cord stimulation (SCS) is a well-established treatment for chronic pain and is supported by numerous studies. However, some recent articles have questioned its efficacy. This article examines a cohort of >1800 patients with SCS from the UK and Ireland National Neuromodulation Registry. It is intended to provide a "real-world" assessment of efficacy and compare its effects with other procedures performed for painful indications. MATERIALS AND METHODS: Quality of life (QoL) data (EuroQoL five-level [EQ5D]) and demographic data were extracted from the National Neuromodulation Registry for all patients (N = 1811) who underwent SCS for chronic pain in 27 centers in the UK between February 2018 and July 2022. These were compared with data from the published literature for other commonly performed elective surgical procedures. RESULTS: The EQ5D utility index increased by a mean of 0.202 in the 1236 patients with paired pre- and postoperative utility scores. The median utility was 0.263 (interquartile range [IQR] = 0.384; n = 1811) preoperatively, whereas at six months after the operation, it was 0.550 (IQR = 0.396; n = 1025), p < 0.0001, Wilcoxon rank sum test. The median utility score at 12 months postoperation was 0.548 (IQR = 0.417; n = 970). There was no difference in utility scores at six months and 12 months after implantation (p = 0.15, Wilcoxon rank sum test). There was a significant improvement in QoL in all five domains of the five-level EQ5D tool at six months after baseline (p < 0.01, for all subcategories), and this was sustained at one year after implantation. The baseline utility was lower than in patients who underwent elective surgery for other painful conditions, and the absolute (and proportionate) increase in utility produced by SCS was greater than that achieved with most other interventions. CONCLUSIONS: SCS increases the QoL in patients requiring surgery for pain. Similar results were seen regardless of SCS indication. When comparing analogous data bases, SCS produces a greater percentage improvement in EQ5D utility than do many other elective surgical procedures for painful conditions, including spinal surgery and some joint replacements.
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INTRODUCTION: The International Neuromodulation Society convened a multispecialty group of physicians based on expertise and international representation to establish evidence-based guidance on the mitigation of neuromodulation complications. This Neurostimulation Appropriateness Consensus Committee (NACC)® project intends to update evidence-based guidance and offer expert opinion that will improve efficacy and safety. MATERIALS AND METHODS: Authors were chosen on the basis of their clinical expertise, familiarity with the peer-reviewed literature, research productivity, and contributions to the neuromodulation literature. Section leaders supervised literature searches of MEDLINE, BioMed Central, Current Contents Connect, Embase, International Pharmaceutical Abstracts, Web of Science, Google Scholar, and PubMed from 2017 (when NACC last published guidelines) to October 2023. Identified studies were graded using the United States Preventive Services Task Force criteria for evidence and certainty of net benefit. Recommendations are based on the strength of evidence or consensus when evidence was scant. RESULTS: The NACC examined the published literature and established evidence- and consensus-based recommendations to guide best practices. Additional guidance will occur as new evidence is developed in future iterations of this process. CONCLUSIONS: The NACC recommends best practices regarding the mitigation of complications associated with neurostimulation to improve safety and efficacy. The evidence- and consensus-based recommendations should be used as a guide to assist decision-making when clinically appropriate.
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Consenso , Terapia por Estimulação Elétrica , Humanos , Terapia por Estimulação Elétrica/métodos , Terapia por Estimulação Elétrica/efeitos adversos , Terapia por Estimulação Elétrica/normas , Terapia por Estimulação Elétrica/instrumentação , Medicina Baseada em Evidências/normasRESUMO
INTRODUCTION: The International Neuromodulation Society (INS) has recognized a need to establish best practices for optimizing implantable devices and salvage when ideal outcomes are not realized. This group has established the Neurostimulation Appropriateness Consensus Committee (NACC)® to offer guidance on matters needed for both our members and the broader community of those affected by neuromodulation devices. MATERIALS AND METHODS: The executive committee of the INS nominated faculty for this NACC® publication on the basis of expertise, publications, and career work on the issue. In addition, the faculty was chosen in consideration of diversity and inclusion of different career paths and demographic categories. Once chosen, the faculty was asked to grade current evidence and along with expert opinion create consensus recommendations to address the lapses in information on this topic. RESULTS: The NACC® group established informative and authoritative recommendations on the salvage and optimization of care for those with indwelling devices. The recommendations are based on evidence and expert opinion and will be expected to evolve as new data are generated for each topic. CONCLUSIONS: NACC® guidance should be considered for any patient with less-than-optimal outcomes with a stimulation device implanted for treating chronic pain. Consideration should be given to these consensus points to salvage a potentially failed device before explant.
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Terapia de Salvação , Estimulação da Medula Espinal , Humanos , Estimulação da Medula Espinal/métodos , Estimulação da Medula Espinal/normas , Terapia de Salvação/métodos , Terapia de Salvação/normas , Consenso , Resultado do Tratamento , Dor Crônica/terapiaRESUMO
INTRODUCTION: The field of neurostimulation for the treatment of chronic pain is a rapidly developing area of medicine. Although neurostimulation therapies have advanced significantly as a result of technologic improvements, surgical planning, device placement, and postoperative care are of equal importance to optimize outcomes. This Neurostimulation Appropriateness Consensus Committee (NACC) project intends to provide evidence-based guidance for these often-overlooked areas of neurostimulation practice. MATERIALS AND METHODS: Authors were chosen based on their clinical expertise, familiarity with the peer-reviewed literature, research productivity, and contributions to the neuromodulation literature. Section leaders supervised literature searches of MEDLINE, BioMed Central, Current Contents Connect, Embase, International Pharmaceutical Abstracts, Web of Science, Google Scholar, and PubMed from the last NACC publication in 2017 to the present. Identified studies were graded using the United States Preventive Services Task Force criteria for evidence and certainty of net benefit. Recommendations are based on evidence strength and consensus when evidence was scant. RESULTS: This NACC project provides guidance on preoperative assessment, intraoperative techniques, and postoperative management in the form of consensus points with supportive evidence. These results are based on grade of evidence, strength of consensus, and expert opinion. CONCLUSIONS: The NACC has given guidance for a surgical plan that encompasses the patient journey from the planning stage through the surgical experience and postoperative care. The overall recommendations are designed to improve efficacy and the safety of patients undergoing these neuromodulation procedures and are intended to apply throughout the international community.
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Dor Crônica , Estimulação da Medula Espinal , Dor Crônica/terapia , Consenso , HumanosRESUMO
OBJECTIVE: To quantify the relationship between the electrical power requirement to achieve pain relief and the position of the active electrode of dorsal root ganglion stimulators within the spinal nerve root exit foramen. MATERIALS AND METHODS: Retrospective analysis of prospectively collected data of 92 consecutive patients undergoing dorsal root ganglion stimulation (DRGS) for chronic pain in a single center. Cervical and sacral cases, and failed trials/explanted DRGS were excluded, so we report on 57 patients with 78 implanted leads. Anteroposterior and lateral fluoroscopic images of the lead in the exit foramen were examined, and the active electrode positions were put into categories depending on their location relative to fixed anatomical landmarks. The clinical outcome and the power requirements for each of these groups of electrodes were then analyzed. Overall pain outcome was assessed by numeric pain rating scale score pre-operatively and post-operatively. RESULTS: There was no significant relationship between power requirements and mediolateral electrode position, although the lowest average was observed with electrode positions directly below the center of the pedicle. On lateral x-ray, the lowest power requirements were observed in the electrodes positioned superodorsally or dorsally within the foramen. Importantly, power requirements in this location were consistently low, while the power requirements in other locations were not only higher but also much more variable. Electrodes in the superodorsal position required a median output power almost four times lower than electrodes in other positions (p = 0.002). Clinical outcome was not significantly related to power requirement or foraminal position. CONCLUSION: Aiming for a superodorsal electrode position on lateral intraoperative fluoroscopy is desirable, since siting leads in this location reduces the required stimulator output power very substantially and thus will extend battery life. Position within the foramen does not determine clinical outcome, and so the implanter can safely aim for the low power site without detriment to the analgesic efficacy of the system.
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Gânglios Espinais/diagnóstico por imagem , Neuroestimuladores Implantáveis/normas , Manejo da Dor/normas , Dor/diagnóstico por imagem , Estimulação da Medula Espinal/normas , Raízes Nervosas Espinhais/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Manejo da Dor/instrumentação , Estudos Prospectivos , Estudos Retrospectivos , Estimulação da Medula Espinal/instrumentação , Adulto JovemRESUMO
BACKGROUND: Trigeminal Neuropathic Pain (TNP) is a chronic facial pain syndrome caused by a lesion or disease affecting one or more branches of the trigeminal nerve. It may, for example, result from accidental injury to a branch of the trigeminal nerve by trauma or during surgery; it may also be idiopathic. TNP is typically constant, in contrast to most cases of the commoner trigeminal neuralgia. In some cases, pain may be refractory to pharmacological treatment. Peripheral nerve field stimulation is recognized as an effective minimally invasive surgical treatment option for this debilitating condition. To date, stimulation has used conventional tonic waveforms, which generate paraesthesia in the stimulated area. This is the first report of the use of paraesthesia-free burst pattern stimulation for TNP. METHODS: Seven patients were treated at the John Radcliffe Hospital for TNP from 2016 to 2018. Mean duration of preoperative symptoms was five years. All patients had exhausted pharmacological measures to limited effect. The initial three patients had tonic stimulation with the subsequent four having burst stimulation. Outcome was assessed using the numeric pain rating scale preoperatively and postoperatively at three and six months and one year. Side-effects and complications were also assessed as well as reduction in analgesic medication use. RESULTS: All patients achieved pain reduction of at least 50% at 6 months (range 50-100%, mean 81%, p = 0.0082). Those in the burst stimulation group were paraesthesia free. One patient developed a postoperative infection for which the system had to be removed and is awaiting reimplantation. There were no other complications in either group. CONCLUSION: Burst stimulation conferred similar pain control to tonic stimulation in our small cohort, and there were similar reductions in pain medication use. An additional benefit of burst stimulation is freedom from paraesthesia. Larger scale studies are needed to further evaluate burst stimulation and compare its efficacy with that of tonic stimulation.
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Terapia por Estimulação Elétrica/métodos , Neuralgia Facial/terapia , Manejo da Dor/métodos , Nervos Periféricos/fisiologia , Estimulação Elétrica Nervosa Transcutânea/métodos , Neuralgia do Trigêmeo/terapia , Adulto , Idoso , Terapia por Estimulação Elétrica/instrumentação , Eletrodos Implantados , Neuralgia Facial/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Manejo da Dor/instrumentação , Estimulação Elétrica Nervosa Transcutânea/instrumentação , Resultado do Tratamento , Neuralgia do Trigêmeo/diagnóstico por imagemRESUMO
OBJECTIVE: Dorsal root ganglion stimulation (DRGS) received its first regulatory approval (CE marking in Europe) in late 2011, and so its use is now almost six years old. Several thousand patients have already been treated, and a landmark trial in lower limb complex regional pain syndrome (CRPS) and causalgia has recently been published. METHODS: In this review we have summarized the literature to date on the use of DRGS in the treatment of neuropathic pain. RESULTS: The results so far are encouraging, with reports of successful use in treating a wide range of indications including postsurgical pain, CRPS, and phantom pain. Treatment of failed back surgery syndrome (FBSS) appears less successful. The therapy is still young, and long term results are not yet available. There is now good randomized clinical trial (RCT) evidence that DRGS provides superior pain relief to spinal cord stimulation for CRPS and causalgia of the lower limb, and produces stimulation that is more posturally stable, with more precise paraesthesia coverage. However evidence of this quality for other indications and pain locations is lacking. CONCLUSION: There is now Class A RCT evidence that DRGS provides superior pain relief to SCS for CRPS and causalgia of the lower limb. In the coming years we hope that randomized controlled trials will be performed on an indication-by-indication basis, which, together with the publication of longer term follow-up data, will provide a more complete understanding of the role of DRGS in the treatment of neuropathic pain syndromes.
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Terapia por Estimulação Elétrica/métodos , Gânglios Espinais/fisiologia , Neuralgia/terapia , Manejo da Dor/métodos , HumanosRESUMO
High-intensity focused ultrasound describes the use of high-intensity focused ultrasound (HIFU) to ablate tumours without requiring an incision or other invasive procedure. This technique has been trialled on a range of tumours including uterine fibroids, prostate, liver and renal cancer. We describe our experience of using HIFU to ablate sacral chordoma in four patients with advanced tumours. Patients were treated under general anaesthetic or sedation using an ultrasound-guided HIFU device. HIFU therapy was associated with a reduction in tumour volume over time in three patients for whom follow up scans were available. Tumour necrosis was reliably demonstrated in two of the three patients. We have established a national trial to assess if HIFU may improve long-term outcome from sacral chordoma, details are given.
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Cordoma/cirurgia , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Região Sacrococcígea/cirurgia , Neoplasias da Coluna Vertebral/cirurgia , Adolescente , Anestesia Geral , Criança , Pré-Escolar , Estudos de Viabilidade , Feminino , Ablação por Ultrassom Focalizado de Alta Intensidade/efeitos adversos , Humanos , Lactente , Masculino , Necrose/etiologia , Equipe de Assistência ao Paciente , Complicações Pós-Operatórias/epidemiologia , Resultado do TratamentoRESUMO
OBJECTIVES: Image-guided brain biopsy is an established method to obtain histopathological diagnosis and guide management for cerebral lesions. The study aimed to establish negative biopsy and symptomatic haemorrhage rates at a single centre, and to assess the influence of factors such as lesion location, final pathology and the use of intra-operative smears. METHODS: A retrospective analysis of all frame-based and frameless stereotactic biopsies carried out over 57 months from July 2006 to March 2011. RESULTS: A total of 351 biopsies were undertaken, 256 frame-based (73%) and 95 frameless (27%). Mean age was 57 years (range 18-87). Negative biopsy rate was 5.1%. There was a significantly greater negative biopsy rate in deep brain biopsies (p = 0.011) and in the cerebellum (p < 0.001). Intra-operative smear significantly reduced negative biopsy rates from 11.1% to 3.7% (p = 0.011). If repeat smear was requested, yet not provided, then the negative biopsy rate was 57.1% (p = 0.0085). The overall symptomatic haemorrhage rate was 3.7%. There was a significant increase in haemorrhage rate in deep versus superficial biopsies (p = 0.023) and a significantly greater haemorrhage rate in lymphoma biopsies (p = 0.015). There was no significant increase in haemorrhage rate in high-grade compared with low-grade tumour biopsies. Mortality rates at 7 and 30 days post-operatively were 0.6% and 1.7%, respectively, with mortality after 7 days unrelated to biopsy. CONCLUSION: We advocate intra-operative histopathological analysis to decrease negative biopsy rates and advise increased caution when undertaking biopsies of deep lesions or suspected lymphoma cases due to the potentially increased risk of haemorrhage.
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Neoplasias Encefálicas/patologia , Neuronavegação , Técnicas Estereotáxicas , Cirurgia Assistida por Computador , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuronavegação/métodos , Estudos Retrospectivos , Técnicas Estereotáxicas/instrumentação , Cirurgia Assistida por Computador/métodos , Adulto JovemRESUMO
The COVID-19 pandemic caught many areas of medicine in a state of unpreparedness for conducting research and completing ongoing projects during a global crisis, including the field of pain medicine. Waves of infection led to a disjointed ability to provide care and conduct clinical research. The American Society of Pain and Neuroscience (ASPN) Research Group has created guidance for pragmatic and ethical considerations for research during future emergency or disaster situations. This analysis uses governmental guidance, scientific best practices, and expert opinion to address procedure-based or device-based clinical trials during such times. Current literature offers limited recommendations on this important issue, and the findings of this group fill a void for protocols to improve patient safety and efficacy, especially as we anticipate the impact of future disasters and spreading global infectious diseases. We recommend local adaptations to best practices and innovations to enable continued research while respecting the stressors to the research subjects, investigator teams, health-care systems, and to local infrastructure.
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We describe the process of establishing a large database for the investigation of craniotomy infection and the preliminary results of this database. The initial results have been used to generate a cost analysis for craniotomy infection. The craniotomy infections database prospectively registers craniotomy cases taking place in the John Radcliffe Hospital. In order to achieve this, each patient's details are registered at the time of operation and followed up to identify cases of infection. Infection was defined strictly according to Centre for Disease Control criteria and validated by at least two members of clinical staff. The first 10 months of data are presented here which identifies a total of 245 craniotomies and 20 verified craniotomy infections. An overall infection rate of 8% is identified, and the cost incurred by the neurosurgery department as a result of craniotomy infections is estimated at £1 85 660 for the 10-month period studied. This amounts to a cost per case of infection of £9283.
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Doenças do Sistema Nervoso Central/economia , Craniotomia/economia , Infecções/economia , Doenças do Sistema Nervoso Central/etiologia , Doenças do Sistema Nervoso Central/mortalidade , Custos e Análise de Custo , Craniotomia/efeitos adversos , Craniotomia/mortalidade , Coleta de Dados/economia , Coleta de Dados/métodos , Bases de Dados Factuais , Feminino , Seguimentos , Humanos , Infecções/etiologia , Infecções/mortalidade , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/economia , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos , Reoperação/economia , Infecção da Ferida Cirúrgica/economiaRESUMO
The authors investigated how effectively adults with severe traumatic brain injury (TBI) can be managed in a district general hospital intensive care unit offering intracranial pressure monitoring (ICPM) receiving advice from a neurosurgical unit. A single-centre case series with retrospective review of prospectively collected information was undertaken of 44 consecutive patients presenting over seven years from January 2003 to January 2010 with severe traumatic brain injury to a single district general hospital intensive care unit serving a population of 500,000 adults. A prospectively entered clinical database was used to obtain information including patient demographics, Glasgow Coma Score (GCS) on admission, ICPM insertion, ICPM-related complications, inpatient mortality and neurosurgical advice. Case notes were used to ratify information and obtain neurorehabilitation clinic functional outcome scores. Forty-four patients were identified (40 male, age range 16-77 years). Mortality in intensive care was 30%. Twenty-eight patients received frontal twist drill ICPM following neurosurgical advice. ICPM had 2 (7%) device malfunctions but no other complications. Twelve additional patients were transferred to tertiary centres. Patients (23 of 31) who survived ICU stay (74%) were referred to neurorehabilitation. Mean clinic follow-up was 14 months. All patients had a Glasgow Outcome Score (GOS) of 3 or 4 at initial clinic assessment. Twenty-two improved to GOS to 4 or 5 at clinic discharge. One patient died prior to clinic discharge. Carefully selected patients with severe TBI can be managed safely and effectively in a district general hospital offering ICPM insertion if transfer to a neurosurgical centre is not possible. Neurosurgical advice regarding patient selection and on-going management is fundamental to provide a good service. Protocol driven therapies provide a useful systematic approach to doctors who do not deal with severe TBI on a routine basis.
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Lesões Encefálicas/terapia , Hospitalização/estatística & dados numéricos , Adolescente , Adulto , Idoso , Lesões Encefálicas/mortalidade , Cuidados Críticos/estatística & dados numéricos , Inglaterra , Métodos Epidemiológicos , Feminino , Hospitais de Distrito/normas , Humanos , Masculino , Pessoa de Meia-Idade , Transferência de Pacientes/estatística & dados numéricos , Encaminhamento e Consulta/estatística & dados numéricos , Resultado do Tratamento , Adulto JovemRESUMO
INTRODUCTION: Spinal cord stimulation (SCS) is a recommended treatment for chronic refractory neuropathic pain. During the COVID-19 pandemic, elective procedures have been postponed indefinitely both to provide capacity to deal with the emergency caseload and to avoid exposure of elective patients to COVID-19. This survey aimed to explore the effect of the pandemic on chronic pain in this group and the views of patients towards undergoing SCS treatment when routine services should resume. METHODS: This was a prospective, multi-centre telephone patient survey that analysed data from 330 patients with chronic pain who were on an SCS waiting list. Questions focussed on severity of pain, effect on mental health, medication consumption and reliance on support networks during the COVID-19 pandemic. Views towards undergoing SCS therapy were also ascertained. Counts and percentages were generated, and chi-square tests of independence explored the impact of COVID-19 risk (very high, high, low) on survey responses. RESULTS: Pain, mental health and patient's ability to self-manage pain deteriorated in around 47%, 50% and 38% of patients, respectively. Some patients reported increases in pain medication consumption (37%) and reliance on support network (41%). Patients showed a willingness to attend for COVID-19 testing (92%), self-isolate prior to SCS (94%) and undergo the procedure as soon as possible (76%). CONCLUSION: Our findings suggest that even during the COVID-19 pandemic, there remains a strong clinical need for patients with chronic pain identified as likely SCS responders to be treated quickly. The current prioritisation of new SCS at category 4 (delayed more than 3 months) is challenged judging by this national survey. These patients are awaiting SCS surgery to relieve severe intractable neuropathic pain. A priority at category 3 (delayed up to 3 months) or in some selected cases, at category 2 are the appropriate priority categories.
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The authors describe symptomatic presentation of glioblastoma within six months of resection of an atypical meningioma, at the same frontal parafalcine cerebral location. The patient had neither prior nor adjuvant radiotherapy nor known genetic risk factors. Possible links between invasive meningioma and transformation of adjacent glial cells or precursors to malignant glioma are discussed.
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Neoplasias Encefálicas/patologia , Glioblastoma/patologia , Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Segunda Neoplasia Primária/patologia , Idoso , Feminino , Humanos , Neoplasias Meníngeas/patologia , Meningioma/patologia , Invasividade NeoplásicaRESUMO
BACKGROUND: To elucidate the efficacy of dorsal root ganglion stimulation in the treatment of chronic neuropathic pain confined to the knee. METHODS: Retrospective analysis of prospectively collected data of 14 consecutive patients undergoing dorsal root ganglion stimulation for chronic knee pain, in a single center. The primary outcome measure was pain reduction assessed by numeric pain rating scale score preoperatively and postoperatively. Secondary outcomes included quantification of percentage of pain area covered by stimulation, and reduction in usage of opioid medications. Responders were defined as patients that experienced a greater than or equal to 50% improvement in their preoperative pain score. RESULTS: Fourteen patients were implanted with dorsal root ganglion stimulator electrodes; 8 had a single L3 lead implanted, 1 patient had a single L4 lead implanted, and 3 patients had 2 leads implanted (L3 and L4). Two patients had their leads explanted: 1 for non-efficacy, and 1 for repeated electrode displacement. The most common indication for surgery was type 2 complex regional pain syndrome, secondary to either trauma or postoperative chronic pain (either knee replacement or arthroscopy). Median preoperative numeric rating scale score was 8.5, median postoperative numeric rating scale score was 2 (P = 0.002, Wilcoxon signed rank test). The median improvement in pain score was 80%. All 12 patients undergoing chronic stimulation were responders. Median coverage of pain area was 85%. All but 1 patient who was on opioid medication prior to surgery had reduced the dosage of regular opioid. CONCLUSIONS: In selected patients, dorsal root ganglion stimulation is an extremely efficacious means of treating otherwise refractory chronic knee pain.
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Artralgia/terapia , Dor Crônica/terapia , Gânglios Espinais , Articulação do Joelho , Neuralgia/terapia , Estimulação da Medula Espinal/métodos , Adulto , Idoso , Artralgia/diagnóstico por imagem , Dor Crônica/diagnóstico por imagem , Feminino , Gânglios Espinais/diagnóstico por imagem , Humanos , Articulação do Joelho/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Neuralgia/diagnóstico por imagem , Medição da Dor/métodos , Estudos Prospectivos , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Chordoma is the most common malignant tumor of the sacrum and is associated with significant neurologic morbidity. Local recurrence is very common, and the long-term prognosis is poor. High-intensity focused ultrasound (HIFU) is a noninvasive and nonionising ablative therapy that has been successful in treating other tumor types and is being evaluated as a new therapy for sacral chordoma. Contrast-enhanced magnetic resonance imaging is typically used to evaluate tumor perfusion following HIFU; however, its utility is limited in poorly perfused tumors. Diffusion-weighted imaging (DWI) provides tissue contrast based on differences in the diffusion of extracellular water without using gadolinium-based contrast agents. We present novel DWI findings following a planned partial HIFU ablation of a large sacral chordoma which had recurred after radiotherapy. Following HIFU, the treated tumor volume demonstrated loss of restriction on DWI correlating with photopenia on positron emission tomography. This suggests successful ablation and tumor necrosis. This novel finding may provide guidance for sequence selection when evaluating HIFU therapy for sacral chordoma and other tumor types for which contrast-enhanced magnetic resonance imaging may have limited utility.