Evaluation of combined radiofrequency and chemical blockade of multi-segmental lumbar sympathetic ganglia in painful diabetic peripheral neuropathy

Advances in the Treatment of Neuropathic Pain by Sympathetic Regulation

PURPOSE OF REVIEW

To explore the mechanism and therapeutic effect of sympathetic nerve regulation on neuropathic pain.

RECENT FINDINGS

A comprehensive search was conducted in the PubMed and CNKI libraries, using the following keywords: stele ganglion block, neuropathic pain, sympathetic nerve block, sympathetic chemical destruction, and sympathetic radiofrequency thermocoagulation. We selected and critically reviewed research articles published in English that were related to sympathetic modulation in the treatment of neuropathic pain. The collected literature will be classified according to content and reviewed in combination with experimental results and clinical cases. Neuropathic pain was effectively treated with sympathetic regulation technology. Its mechanism includes the inhibition of sympathetic nerve activity, regulation of the inflammatory response, and inhibition of pain transmission, which greatly alleviates neuropathic pain in patients. Stellate ganglion blocks, thoracic and lumbar sympathectomies, chemical destruction, and radiofrequency thermocoagulation have been widely used to treat neuropathic pain. Sympathetic regulation can effectively relieve pain symptoms and improve the patient's quality of life by inhibiting sympathetic nerve activity, reducing the production and release of pain-related mediators, and inhibiting pain transmission. CT-guided radiofrequency thermocoagulation of the thoracic and lumbar sympathetic nerves is effective and durable, with few complications, and is recommended as a treatment for intractable neuropathic pain.

A Systematic Guideline by the ASPN Workgroup on the Evidence, Education, and Treatment Algorithm for Painful Diabetic Neuropathy: SWEET

Introduction

Painful diabetic neuropathy (PDN) is a leading cause of pain and disability globally with a lack of consensus on the appropriate treatment of those suffering from this condition. Recent advancements in both pharmacotherapy and interventional approaches have broadened the treatment options for PDN. There exists a need for a comprehensive guideline for the safe and effective treatment of patients suffering from PDN.

Objective

The SWEET Guideline was developed to provide clinicians with the most comprehensive guideline for the safe and appropriate treatment of patients suffering from PDN.

Methods

The American Society of Pain and Neuroscience (ASPN) identified an educational need for a comprehensive clinical guideline to provide evidence-based recommendations for PDN. A multidisciplinary group of international experts developed the SWEET guideline. The world literature in English was searched using Medline, EMBASE, Cochrane CENTRAL, BioMed Central, Web of Science, Google Scholar, PubMed, Current Contents Connect, Meeting Abstracts, and Scopus to identify and compile the evidence for diabetic neuropathy pain treatments (per section as listed in the manuscript) for the treatment of pain. Manuscripts from 2000-present were included in the search process.

Results

After a comprehensive review and analysis of the available evidence, the ASPN SWEET guideline was able to rate the literature and provide therapy grades for most available treatments for PDN utilizing the United States Preventive Services Task Force criteria.

Conclusion

The ASPN SWEET Guideline represents the most comprehensive review of the available treatments for PDN and their appropriate and safe utilization.

4. Painful diabetic polyneuropathy

INTRODUCTION

Pain as a symptom of diabetic polyneuropathy (DPN) significantly lowers quality of life, increases mortality and is the main reason for patients with diabetes to seek medical attention. The number of people suffering from painful diabetic polyneuropathy (PDPN) has increased significantly over the past decades.

METHODS

The literature on the diagnosis and treatment of diabetic polyneuropathy was retrieved and summarized.

RESULTS

The etiology of PDPN is complex, with primary damage to peripheral nociceptors and altered spinal and supra-spinal modulation. To achieve better patient outcomes, the mode of diagnosis and treatment of PDPN evolves toward more precise pain-phenotyping and genotyping based on patient-specific characteristics, new diagnostic tools, and prior response to pharmacological treatments. According to the Toronto Diabetic Neuropathy Expert Group, a presumptive diagnosis of "probable PDPN" is sufficient to initiate treatment. Proper control of plasma glucose levels, and prevention of risk factors are essential in the treatment of PDPN. Mechanism-based pharmacological treatment should be initiated as early as possible. If symptomatic pharmacologic treatment fails, spinal cord stimulation (SCS) should be considered. In isolated cases, where symptomatic pharmacologic treatment and SCS are unsuccessful or cannot be used, sympathetic lumbar chain neurolysis and/or radiofrequency ablation (SLCN/SLCRF), dorsal root ganglion stimulation (DRGs) or posterior tibial nerve stimulation (PTNS) may be considered. However, it is recommended that these treatments be applied only in a study setting in a center of expertise.

CONCLUSIONS

The diagnosis of PDPN evolves toward pheno-and genotyping and treatment should be mechanism-based.

Efficacy of Radiofrequency Thermocoagulation of the Thoracic Sympathetic Nerve versus Chemical Excision in Pain Caused by Raynaud's Disease

Objective

To investigate the effectiveness and safety of computed tomography (CT)-guided radiofrequency thermocoagulation (RFTC) of the thoracic sympathetic nerve versus chemical resection (CTS) for the treatment of pain caused by Raynaud's disease.

Methods

Patients who underwent CTS or thoracic sympathetic nerve RFTC between March 2012 and March 2021 were enrolled in this retrospective study. There were 28 cases in the alcohol group (Group A) and 44 in the radiofrequency group (Group R). Visual analog scores (VAS) were collected from patients at different time points, as well as preoperative and postoperative finger end perfusion index (PI) and hand temperature (T). The efficiency, postoperative recurrence rate, complications, and improvement in postoperative quality of life were observed in both groups.

Results

Pain scores at different follow-up times after surgery decreased in both groups compared to the preoperative period (P < 0.05). Postoperative T and PI were higher in both groups than preoperatively all (P < 0.05). The recurrence rate was higher in the R group than in the A group. Postoperative complications were observed in 13.6% and 25% of patients in groups R and A, respectively. Meanwhile, the postoperative quality of life improved in both groups, but the radiofrequency (RF) group was better than the alcohol group in terms of improvement in quality of life (P < 0.05).

Conclusion

Both CT-guided CTS and RFTC of the thoracic sympathetic nerve provided good treatment outcomes. However, the RF group was superior to the alcohol group in terms of complication rate and quality of life improvement.

Efficacy and safety of sympathetic radiofrequency thermocoagulation in the treatment of cold hypersensitivity

Background

Cold hypersensitivity (CH) is a sensation of cold in the limbs and (or) body of a patient in an environment that is not considered cold by unaffected people, or a strong feeling of cold at a relatively low temperature. However, the currently available treatments are limited and often unsatisfactory. This study aimed to evaluate the clinical efficacy and safety of the sympathetic radiofrequency thermocoagulation (RF-TC) technique in patients with CH disorder.

Methods

The study is a retrospective analysis. A total of 71 were entered into the final analysis and all patients underwent computed tomography-guided thoracic (lumbar) sympathetic nerve RF-TC on an elective basis. The values of terminal temperature (T) and perfusion index (PI) of patients before and after treatment were recorded. Patients were followed up clinically at regular intervals and their Visual Analog Scale (VAS) and Pittsburgh Sleep Quality Index (PSQI) scores were recorded to detect postoperative complications and assess patient satisfaction with the treatment.

Results

All patients completed the radiofrequency treatment. Compared with the preoperative period, VAS and PSQI scores were significantly lower at all postoperative time periods (P < 0.001). Patients had significantly higher postoperative terminal temperatures and perfusion indices on the right and left sides than before surgery (P < 0.001). The overall patient satisfaction score was 4 (3–5) at 3 years of postoperative follow-up. There were 20 recurrences (28.2%). The main postoperative complications were postoperative local pain and compensatory hyperhidrosis. No other adverse events or deaths were observed.

Conclusion

RF-TC for CH could be a feasible, effective, and safe treatment option to improve patients' symptoms of cold sensation. Yet, more researches are needed to verify this potentially efficient and standardized treatment.

Advances in Interventional Therapies for Painful Diabetic Neuropathy: A Systematic Review

BACKGROUND

Painful diabetic neuropathy (PDN) is one of the major complications of diabetes mellitus. It is often debilitating and refractory to pharmaceutical therapies. Our goal was to systematically review and evaluate the strength of evidence of interventional management options for PDN and make evidence-based recommendations for clinical practice.

METHODS

We searched PubMed, Scopus, Google Scholar, and Cochrane Llibrary and systematically reviewed all types of clinical studies on interventional management modalities for PDN.

RESULTS

We identified and analyzed 10 relevant randomized clinical trials (RCTs), 8 systematic reviews/meta-analyses, and 5 observational studies of interventional modalities for PDN using pain as primary outcome. We assessed the risk of bias in grading of evidence and found that there is moderate to strong evidence to support the use of dorsal column spinal cord stimulation (SCS) in treating PDN in the lower extremities (evidence level: 1B+), while studies investigating its efficacy in the upper extremities are lacking. Evidence exists that acupuncture and injection of botulinum toxin-A provide relief in pain or muscle cramps due to PDN with minimal side effects (2B+/1B+). Similar level of evidence supports surgical decompression of lower limb peripheral nerves in patients with intractable PDN and superimposed nerve compression (2B±/1B+). Evidence for sympathetic blocks or neurolysis and dorsal root ganglion (DRG) stimulation is limited to case series (2C+).

CONCLUSIONS

Moderate to strong evidence exists to support the use of SCS in managing lower extremity pain in patients who have failed conventional medical management for PDN. Acupuncture or injection of botulinum toxin-A can be considered as an adjunctive therapy for PDN. Surgical decompression of peripheral nerves may be considered in patients with PDN superimposed with nerve compression. High-quality studies are warranted to further evaluate the safety, efficacy, and cost-effectiveness of interventional therapies for PDN.

Predictive Value of Contrast-Enhanced Ultrasound in Chemical Lumbar Sympathectomy for End-Stage Arteriosclerosis Obliterans of the Lower Extremities

Introduction

The therapeutic effect of chemical lumbar sympathectomy (CLS) on ischemic diseases of the lower limbs varies greatly among individuals. The time to peak (TTP) response in contrast-enhanced ultrasound (CEUS) can reflect the perfusion disorder of the calf skeletal muscle and the collateral circulation. In this study we evaluated the predictive value of CEUS in patients treated with CLS for end-stage atherosclerotic occlusive disease of the lower extremity (ASO-LE).

Methods

This was a prospective study that included patients with end-stage ASO-LE and moderate to severe pain who had undergone a CEUS examination and CLS procedure and who were observed for 12 months after surgery. The patients’ characteristics and prognostic factors, including lower limb pain score, skin temperature, walking distance, and ulcer and gangrene healing, were recorded.

Results

Fifty-eight patients with a mean age of 66.24 (range 58–78) years were included in the study, of whom 42 (71.41%) were men. Following the CLS procedure, the numerical rating scale (NRS)-measured pain decreased significantly, and the skin temperature of the affected limb increased significantly (P < 0.05). The satisfaction rate of lower limb pain relief 1 year after operation was 53.45%. Correlation analysis showed that preoperative TTP response was correlated with the NRS score and skin temperature of the affected limb at 6 months and 12 months post surgery (P < 0.05). The binary logistic regression analysis indicated that a longer preoperative TTP response was associated with a higher risk of poor pain relief after CLS (odds ratio 1.126, 95% confidence interval 1.058–1.205). The receiver operating characteristic curve showed that preoperative TTP response had a certain predictive value on CLS treatment effect, with a sensitivity and specificity of 81.5% and 83.9%, respectively. When the preoperative TTP response was > 77.5, the risk of poor response after CLS increased.

Conclusions

Preoperative TTP response was able to predict the therapeutic effect of CLS to a certain extent, and thus may aid physicians in determining the choice of CLS treatment for patients with ASO-LE.

Trial Registration

Chinese Clinical Trial Registry: ChicTR1900028424 (principal investigator: Yue Wu; date of registration: 21 December 2019).

Supplementary Information

The online version contains supplementary material available at 10.1007/s40122-021-00347-9.

Bier block as a successful management of a patient with intractable complex regional pain syndrome (CRPS) type 1: A case report

Bier block was successful in the pain management of complex regional pain syndrome (CRPS) type 1.

Alpha 1 adrenoceptor expression in skin, nerves and blood vessels of patients with painful diabetic neuropathy

Diabetic neuropathy (dNP) patients often suffer from severe neuropathic pain. It was suggested that alpha-1 adrenoceptor (α₁-AR) hyperresponsiveness contributes to pain in dNP. The aim of our study was to quantify α₁-AR expression using immunohistochemistry in skin biopsies of nine patients with painful diabetic neuropathy compared to 10 healthy controls. Additionally, the association between α₁-AR expression and activation with spontaneous and sympathetically maintained pain (SMP) induced by intradermal injection of the α₁-agonist phenylephrine was investigated. For control purposes the α₂-agonist clonidine was injected in a different session. We found that dermal nerve density was significantly lower in dNP than in controls. However, α₁-AR expression was significantly greater on cutaneous blood vessels and keratinocytes of dNP patients than controls. A similar trend, which failed to reach significance, was observed for dermal nerves. Intradermal injection of phenylephrine induced only minor pain, which resolved after a few minutes. Adrenergically evoked pain persisted for more than 15 min in only one patient, but none of the patients fulfilled the criteria for SMP (pain increase after injection of phenylephrine and decrease after clonidine). In conclusion, our results imply that SMP does not occur in dNP. However, elevated expression of α₁-AR on keratinocytes and dermal blood vessels is an important finding, since this could contribute to dNP progression and supports the theory of receptor up-regulation of denervated structures. The implications of this α₁-upregulation should be examined in further studies.

Expert consensus of Chinese Association for the Study of Pain on the radiofrequency therapy technology in the Department of Pain

On the basis of continuous improvement in recent years, radiofrequency therapy technology has been widely developed, and has become an effective method for the treatment of various intractable pain. Radiofrequency therapy is a technique that uses special equipment and puncture needles to output ultra-high frequency radio waves and accurately act on local tissues. In order to standardize the application of radiofrequency technology in the treatment of painful diseases, Chinese Association for the Study of Pain (CASP) has developed a consensus proposed by many domestic experts and scholars.

Interventional Radiofrequency Treatment for the Sympathetic Nervous System: A Review Article

Introduction

Interventional techniques such as radiofrequency (RF) treatment can be used to interrupt pain signals transmitted through the sympathetic nervous system (SNS). RF treatments including the pulsed (PRF) and continuous (CRF) modalities show enhanced control over lesion size and enhanced ability to confirm accurate positioning compared to other interventional methods. PRF also acts to reduce the area of the lesion. In this article, we characterize the currently available evidence supporting the use and efficacy of RF treatments in sympathetically mediated pain (SMP) conditions.

Study Design

A comprehensive literature review.

Methods

A PubMed and Cochrane Library database search was performed for human studies applying RF treatment at sympathetic sites (sphenopalatine ganglion, stellate ganglion, cervical, thoracic, or lumbar sympathetic ganglia, celiac plexus, splanchnic nerves, superior hypogastric plexus, and ganglion impar) between January 1970 to May 2020. Data were extracted, summarized into tables, and qualitatively analyzed.

Results

PRF and CRF both show promise in relieving SMP conditions, such as complex regional pain syndrome (CRPS), pain in the perineal region, headache and facial pain, and oncologic and non-oncologic abdominal pain, in addition to other types of pain, with minimal complications. Furthermore, in most comparative studies, outcomes using RF treatments exceeded other interventional techniques, such as anesthetic block and chemical neurolysis.

Conclusions

RF treatments can be effective in carefully selected patients who are refractory to conservative management. However, further randomized controlled studies are needed prior to implementing it into common practice.

Unilateral Dorsal Root Ganglion Stimulation Lead Placement With Resolution of Bilateral Lower Extremity Symptoms in Diabetic Peripheral Neuropathy

Dorsal root ganglion stimulation (DRG-S) is a form of neuromodulation that can target specific dermatomes to obtain better coverage of the distal extremity. Previously proposed mechanisms of action for DRG-S focused on the dorsal root ganglion (DRG) itself, without consideration of orthodromic effects in the dorsal horn and antidromic effects on the nerve root and sympathetic chain. Diabetic peripheral neuropathy (DPN) is an axonal neuropathy that affects around half of all patients with diabetes mellitus, causing severe pain and sensory impairment in the distal extremities. We present a case of a patient with DPN in both feet, in addition to low back pain, who underwent a DRG-S trial with right T12 and S1 leads. The trial was performed unilaterally for seven days, allowing the patient to compare the treated versus the untreated (left) side. Pain, disability, general health status, and quality of life measures improved significantly. In addition to the significant pain relief in the low back and feet, the patient had near resolution of other DPN-related symptoms, including numbness, bluish discoloration, and allodynia of both feet. He also demonstrated functional and psychological benefits with only a single-sided lead. Overall, the placement of unilateral T12 and S1 DRG-S leads resulted in symmetric improvement of DPN symptoms. A possible mechanism of action is antidromic propagation of action potential signaling into the sympathetic chain to a central ganglion and then to the contralateral sympathetic chain. Given the DRG's ability to directly affect afferent sympathetic fibers with low-frequency stimulation, DRG-S may be an effective neuromodulatory treatment for DPN.