Thoracic Sympathetic Ganglia Research Articles

Evaluation of thoracic sympathetic ganglion block as a predictor for response to ketamine infusion therapy and spinal cord stimulation in patients with chronic upper extremity pain.

To investigate the predictive value of thoracic sympathetic ganglion block (TSGB) in response to ketamine infusion therapy (KIT) and spinal-cord stimulation (SCS) in patients with chronic upper-extremity pain including complex regional pain syndrome (CRPS). Retrospective. Tertiary hospital single-center. Patients who underwent TSGB receiving KIT or SCS within a 3-year window. Positive TSGB outcomes were defined as ≥2 0-10 Numerical Rating Scale (NRS) score reduction at 2 weeks post-procedure. Positive KIT and SCS outcomes were determined by ≥2 NRS score reduction at 2-4 weeks post-KIT and ≥4 NRS score reduction at 2-4 weeks post-SCS implantation, respectively. Among 207 patients who underwent TSGB, 38 received KIT and 34 underwent SCS implantation within 3 years post-TSGB; 33 patients receiving KIT and 32 patients receiving SCS were included. Among 33 patients who received KIT, 60.6% (n = 20) reported a ≥ 2 0-10 NRS pain-score reduction. Positive response to TSGB occurred in 70.0% (n = 14) KIT responders, significantly higher than that in 30.8% (n = 4) KIT non-responders. Multivariable analysis revealed a positive association between positive responses to TSGB and KIT (OR 7.004, 95% CI 1.26-39.02). Among 32 patients who underwent SCS implantation, 68.8% (n = 22) experienced short-term effectiveness. Positive response to TSGB was significantly higher in SCS responders (45.5%, n = 10) than in non-responders (0.0%). However, there were no associations between pain reduction post-TSGB and that post-KIT or post-SCS. A positive response to TSGB is a potential predictor for positive KIT and SCS outcomes among patients with chronic upper-extremity pain, including CRPS.

Thoracic sympathetic ganglion blocks: real-world outcomes in 207 chronic pain patients

BackgroundThoracic sympathetic ganglion block (TSGB) is a procedure to manage sympathetically maintained upper extremity pain (sympathetically maintained pain). To date, only a few studies have evaluated the clinical effectiveness of...

Successful neurolytic thoracic sympathetic ganglion block using C-arm fluoroscopic cone-beam computed tomography in patients with postmastectomy pain syndrome: a report of 3 cases

BackgroundPostmastectomy pain syndrome involves persistent neuropathic and sympathetically maintained neuropathic pain that can be improved using a thoracic sympathetic ganglion block. However, conventional fluoroscopic procedures pose technical difficulties and are associated with potential severe complications. We report the use of C-arm fluoroscopic cone-beam computed tomography to enhance procedural success and treatment safety.Case presentationThree women diagnosed with postmastectomy pain syndrome and experiencing persistent pain underwent C-arm fluoroscopic cone-beam computed tomography-assisted ethanol neurolytic thoracic sympathetic ganglion block. Pain severity decreased substantially after the procedure. The therapeutic effects were sustained for 12 months in cases 1 and 2 and for 5 months in case 3. All patients experienced a remarkable decrease in allodynia and hyperalgesia intensities.ConclusionC-arm fluoroscopic cone-beam computed tomography-assisted neurolytic thoracic sympathetic ganglion block offers a valuable alternative for managing otherwise intractable postmastectomy pain syndrome before considering more invasive techniques.

Anatomical variation of sympathetic ganglia in R4+R5 sympathicotomy for primary palmar axillary hyperhidrosis.

R4+R5 sympathicotomy is one of the standard surgical treatments for primary palmar axillary hyperhidrosis (PAH), but the reported outcomes vary. Anatomical variation of sympathetic ganglia is hypothesized to be a cause for this phenomenon. The sympathetic ganglia could be visualized via near-infrared (NIR) fluorescent thoracoscopy, we utilize this novel technique to observe the anatomical variation of sympathetic ganglia T3 and T4 and investigate its relationship with surgical outcomes. This is a prospective multi-center cohort study. All patients received intravenous indocyanine green (ICG) infusion 24 hours preoperatively. Anatomical variation of sympathetic ganglia T3 and T4 was observed via fluorescent thoracoscopy. Standard R4+R5 sympathicotomy was performed regardless of anatomical variation. Patients were followed up for the therapeutic outcome. One hundred and sixty-two patients in total were enrolled in this study and 134 patients with bilateral clearly visualized thoracic sympathetic ganglia (TSG) were included. The success rate of fluorescent imaging of thoracic sympathetic ganglion was 82.7%. The T3 ganglion was shifted downward on 32 sides (11.9%) and no upward-shifted ganglion was identified. The T4 ganglion was shifted downward on 52 sides (19.4%) and no upward-shifted ganglion was identified. All patients underwent R4+R5 sympathicotomy and no perioperative death or severe complication occurred. The total improvement rates on palmar sweating at short-term and long-term follow-up were 98.1% and 95.1%, respectively. There were significant differences between T3 normal and T3 variation subgroups both in short-term (P=0.049) and long-term (P=0.032) follow-ups. The total improvement rates on axillary sweating at short-term and long-term follow-ups were 97.0% and 89.6%, respectively. No significant difference was found between T4 normal and T4 variation subgroups both in short-term and long-term follow-ups. No significant difference was found between normal and variation subgroups on the degree of compensatory hyperhidrosis (CH). NIR fluorescent thoracoscopy provides clear identification of anatomical variations of sympathetic ganglia during R4+R5 sympathicotomy. The improvement of palmar sweating was significantly affected by anatomical variation of T3 sympathetic ganglia.

Treatment of stellate ganglion block in diseases: Its role and application prospect

The stellate ganglion (SG), as a type of sympathetic ganglion, consists of the sixth and seventh cervical vertebrae and the first thoracic sympathetic ganglia. SG block (SGB) is a minimally invasive injection that aims to inject low-concentration local anesthetics to induce a broad sympathetic blocking effect near the SG. There have been no changes and progress in the clinical application of SGB since the 1830s due to several potential risks, including hematoma from blood vessel injury, hoarseness from recurrent laryngeal nerve injury, and cardiopulmonary arrest. The feasibility and safety of SGB have greatly improved since the appearance of ultrasound-guided SGB. In recent years, SGB has been widely applied in the field of non-anesthesiology sedation, with significant therapeutic effects on pain, immunological diseases, somnipathy, psychological disorders, arrhythmias, and endocrine diseases. The present study reviews the present application of SGB in clinical practice.

Anatomical variations of the thoracic sympathetic ganglions and their effects on sympathicotomy for primary palmar hyperhidrosis

PurposeThe results and side effects of sympathicotomy for primary palmar hyperhidrosis (PPH) can vary due to anatomical variations of the sympathetic ganglions. The aim of our study was to clarify anatomical variations of the sympathetic ganglions by near-infrared (NIR) thoracoscopy and determine their effects on sympathicotomy for PPH.Methods The cases of 695 consecutive patients with PPH treated with either R3 or R4 sympathicotomy either by normal thoracoscopy or by NIR fluorescent thoracoscopy between March 2015 and June 2021 were retrospectively reviewed and followed up.ResultsThe variation rate of third and fourth ganglions was 14.7% and 13.3% on the right side and 8.3% and 11.1% on the left side. Real T3 sympathicotomy (RTS3) was more effective than real T4 sympathicotomy (RTS4) in the short-term and long-term follow-up (p < 0.001 and p < 0.001, respectively). RTS3 was more satisfactory than RTS4 in the long-term follow-up (p = 0.03), but no significant difference was found in the short-term follow-up (p = 0.24). The incidence and severity of compensatory hyperhidrosis (CH) in the areas of the chest and back in the RTS4 group were significantly lower than those in the RTS3 group according to both the short-term results (12.92% vs. 26.19%, p < 0.001; 17.97% vs. 33.33%, p = 0.002, respectively) and the long-term results (19.66% vs. 28.57%, p = 0.017; 21.35% vs. 34.52%, p < 0.001, respectively).ConclusionsRTS3 may be more effective than RTS4 for PPH. However, RTS4 appears to be associated with a lower incidence and severity of CH in the areas of the chest and back than RTS3. NIR intraoperative imaging of thoracic sympathetic ganglions may improve the quality of sympathicotomy surgeries.

Stellate Ganglia and Cardiac Sympathetic Overactivation in Heart Failure.

Heart failure (HF) is a major public health problem worldwide, especially coronary heart disease (myocardial infarction)-induced HF with reduced ejection fraction (HFrEF), which accounts for over 50% of all HF cases. An estimated 6 million American adults have HF. As a major feature of HF, cardiac sympathetic overactivation triggers arrhythmias and sudden cardiac death, which accounts for nearly 50-60% of mortality in HF patients. Regulation of cardiac sympathetic activation is highly integrated by the regulatory circuitry at multiple levels, including afferent, central, and efferent components of the sympathetic nervous system. Much evidence, from other investigators and us, has confirmed the afferent and central neural mechanisms causing sympathoexcitation in HF. The stellate ganglion is a peripheral sympathetic ganglion formed by the fusion of the 7th cervical and 1st thoracic sympathetic ganglion. As the efferent component of the sympathetic nervous system, cardiac postganglionic sympathetic neurons located in stellate ganglia provide local neural coordination independent of higher brain centers. Structural and functional impairments of cardiac postganglionic sympathetic neurons can be involved in cardiac sympathetic overactivation in HF because normally, many effects of the cardiac sympathetic nervous system on cardiac function are mediated via neurotransmitters (e.g., norepinephrine) released from cardiac postganglionic sympathetic neurons innervating the heart. This review provides an overview of cardiac sympathetic remodeling in stellate ganglia and potential mechanisms and the role of cardiac sympathetic remodeling in cardiac sympathetic overactivation and arrhythmias in HF. Targeting cardiac sympathetic remodeling in stellate ganglia could be a therapeutic strategy against malignant cardiac arrhythmias in HF.

Post Mastectomy and Radiation Therapy - Complex Regional Pain Syndrome -A Case Report

Complex regional pain syndrome which is a rare syndrome following an injury or trauma, is an extremely painful condition. Diagnosis of this condition is not easy. They present with various symptoms like allodynia, hyperalgesia, asymmetry of temperature and sweating ,restricted range of motion. Identifying and treating this condition at earlier stage is important. There are different treatment options like pharmacological (NSAIDs, Anticonvulsants, Antidepressants, neuromodulators) and interventional techniques like Stellate ganglion block, Thoracic Sympathetic Ganglion block, Lumbar sympathetic block, Neurostimulation.&#x0D; In this case report we present a case of 52 year old female post mastectomy and radiation therapy developing CRPS of left upper limb, which was diagnosed and managed successfully with diagnostic thoracic sympathetic ganglion block followed by therapeutic radiofrequency ablation.

Effects of thoracic sympathetic stimulation on palmar perfusion: a preliminary study in pigs.

Ablation of the upper thoracic sympathetic ganglia that innervates the hands is the most effective and permanent cure of palmar hyperhidrosis. However, this type of sympathectomy causes irreversible neural damage and may result in severe compensatory hyperhidrosis. This experiment is designed to confirm the hypothesis, in which the stimulation of T2 sympathetic chain leads to increased palmar microcirculation, and thus results in treating hyperhidrosis. In this study, we used electric stimulation to induce reversible blockade of the sympathetic ganglion in pigs and investigated its effect on palmar perfusion. An electrode was inserted to the T2 sympathetic ganglion of the pig through three different approaches: open dorsal, thoracoscopic, and fluoroscopy-guided approaches. Electric stimulation was delivered through the electrode using clinically available pulse generators. Palmar microcirculation was evaluated by laser speckle contrast imaging. The T2 sympathetic ganglion of the pig was successfully accessed by all the three approaches, as confirmed by changes in palmar microcirculation during electric stimulation. Similar effects were not observed when the electrode was placed on the T4 sympathetic ganglion or off the sympathetic trunk. We established a large animal model to verify the effect of thoracic sympathetic stimulation. Electric stimulation can be used for sympathetic blockade, as confirmed by increased blood perfusion of the palm. Our work suggests that sympathetic stimulation is a potential solution for palmar hyperhidrosis.

Chronic Diarrhea and Weight Loss in an 18-month-old Boy.

Chronic Diarrhea and Weight Loss in an 18-month-old Boy.

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

IntroductionInterventional 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 DesignA comprehensive literature review.MethodsA 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.ResultsPRF 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.ConclusionsRF 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.

Functional Cardiological Changes Resulting from Thoracoscopic Thoracic Sympathectomy: Systematic Review

Hyperhidrosis is a condition resulting from a systemic sympathetic hyperactivity. The gold standard treatment is the resection or surgical ablation of the paravertebral sympathetic chain: the endoscopic thoracoscopic sympathectomy (ETS). Non-cardiac thoracic surgeries carry a considerable incidence of pathological postoperative cardiac events, raising attention to possible worsen cardiac functional capacity after the resection of a pair of thoracic sympathetic ganglia. The aim of this study is to investigate literature evidences of postoperative cardiovascular functional changes on patients submitted to ETS as treatment for hyperidrosis. This is a systematic review of the literature. Clinical studies published between January 1999 and April 2019 were analyzed. The PICO strategy was used to construct the question of systematic reviews research. The process of selecting articles was organized according to PRISMA Diagram. The search in electronic databases resulted in seven articles, of which one was excluded for being out of scope of the research, leaving six articles. All studies showed a pattern of heart rate (HR) reduction after endoscopic thoracic sympathectomy. It was suggested a relation between the extension of the procedure and the presence of cardiac functional alterations. There was an improvement in myocardial physical conditioning and maintenance of functional capacity. To elucidate the real mechanisms involved in the maintenance of myocardial function, and even its improvement, it is necessary to develop further studies that directly evaluate them.

Surgical cardiac sympathetic denervation in patients with VT storm: long term follow-up data

Abstract Background Surgical Cardiac Sympathetic Denervation (CSD) is a procedure which involves surgical removal of terminal cervical and thoracic sympathetic ganglion for reducing sympathetic discharge to the heart. CSD is usually performed as a last desperate measure in treatment of ventricular tachycardia (VT). We report here the clinical profile and long-term follow-up of all our patients who underwent CSD (unilateral or bilateral) predominantly upfront prior to considering catheter ablation of VT for VT storm. Material and methods We retrospectively collected data of all patients who underwent CSD for VT storm between year 2010 till 2019. Success of CSD was defined as successful discharge of patient from the hospital after the procedure more than 75% decrease in the frequency of VT after two weeks of surgical procedure. Results A total of 65 patients underwent CSD in the above-mentioned period and the average duration of follow-up was 28 months. The clinical parameters, demographic data and outcome analysis is provided in details in table 1. Only 14 (21.5%) patients underwent attempt of catheter ablation of VT prior to considering CSD. CSD was successful in 53 (81.5%) of patients. There was a significant decline in the incidence of number of ICD or external shocks before and after CSD (25.2±39.4 vs 1.09±2.9) respectively. There was no significant effect of CSD on ejection fraction. None of the available clinical parameters predicted the success of CSD. Discussion and conclusion The current retrospective analysis reemphasize the role of surgical CSD in treatment of patients with VT storm. As in predominant patient's CSD was performed even before the attempting catheter-based ablation, it brings in a new dimension in the treatment of VT. Efficacy of CSD (81.5%) in experienced hand is equivalent or even better than catheter-based ablation in patients with VT storm. Funding Acknowledgement Type of funding source: None

Incidence of inadvertent intercostal or epidural spread during thoracic sympathetic ganglion block

BackgroundSympathetic blocks (SBs) have been used widely to relieve the symptoms of sympathetically maintained pain (SMP). The thoracic sympathetic ganglion is not separated from somatic nerves by muscles and connective tissue. The upper thoracic ganglion runs along the posterior surface of the vertebral column in close proximity to the adjacent epidural region. This anatomical difference leads to frequent epidural and intercostal spread in cases of thoracic SBs. The purpose of this study was to investigate the incidence of inadvertent intercostal and epidural injections during thoracic SBs.MethodsTwenty-two patients who were suffering from complex regional pain syndrome or lymphedema after breast cancer surgery were managed with two or three times of thoracic SBs. Therefore, injections of 63 thoracic SBs from 22 patients were enrolled in this study. An investigator who did not attend the procedure evaluated the occurrence of intercostal or epidural spread using anteroposterior fluoroscopic images.ResultsThe overall incidence of inadvertent intercostal or epidural spread of contrast was 47.5%. Among the inadvertent injections, intercostal spread (34.9%) was more frequent than epidural spread (12.6%). Only 52.5% of the thoracic SBs demonstrated successful contrast spread without any inadvertent spread. The mean difference in skin temperature between the blocked and unblocked sides was 2.5 ± 1.8ºC. Fifty-nine (93.6%) injections demonstrated more than 1.5ºC difference.ConclusionsThoracic SBs showed a high incidence (47.5%) of inadvertent epidural or intercostal injection. Thus, special attention is required for the diagnosis of SMP or the injection of any neurolytic agent around sympathetic ganglion.

Anatomic variations of the intrathoracic nerves and the neural connections of the second and third thoracic sympathetic ganglia to the brachial plexus

This study investigated morphological variations of the intrathoracic nerves and the neural connections of the second and third thoracic sympathetic ganglia to the brachial plexus based on the existence of the intrathoracic nerves and the rami communicantes. Fifty thoracic sympathetic trunks from 26 Korean adult cadavers were used. The first intrathoracic nerve connecting the first and second thoracic nerves was observed on 36 sides (72%), and the second intrathoracic nerve connecting the second and third thoracic nerves was found on three sides (6%). There were either one (62%) or two (10%) first intrathoracic nerves, and only one second intrathoracic nerve (6%). The neural connections of the second and third thoracic sympathetic ganglia to the first thoracic nerve were classified into three types based on the existence of the intrathoracic nerves: Type I (68%) had only the first intrathoracic nerve, Type II (26%) had no intrathoracic nerve, and Type III (6%) had both the first and second intrathoracic nerves. Types I, II, and III were further subdivided into 10, 6, and 3 types, respectively, according to the types of the rami communicantes arising from the second and third thoracic sympathetic ganglia. Improved knowledge of the variations in intrathoracic nerves and upper thoracic sympathetic ganglia will be helpful to thoracic surgeons when they are disrupting the sympathetic supply to the hand for treating palmar hyperhidrosis, and contribute to successful diagnoses and treatments.

How does stellate ganglion block alleviate immunologically-linked disorders?

BackgroundThe stellate ganglion is an autonomic nervous ganglion, formed by the fusion of the inferior cervical sympathetic ganglion and the first thoracic sympathetic ganglion, which is present in about 80% of people. It is anterior to the neck of the first rib and contains neurons that supply sympathetic innervation to the head and neck. Injection of local anesthetics near the stellate ganglion (stellate ganglion block; SGB) has been used for multiple clinical indications including sympathetic-mediated pain and vascular insufficiency syndromes of the upper extremity. In addition, reports on SGB having significant impact on conditions linked to immune dysfunction have been published for a century, but the mechanisms of SGB action have been poorly understood. HypothesisSGB hinders the sympathetic innervation of the immune organs, thus modulating the immune system activity and leading to the alleviation of the disease. EvidenceAll primary (thymus and bone marrow) and secondary immune organs (spleen, lymph nodes, mucosa-associated lymphoid tissue) receive a substantial sympathetic innervation, with norepinephrine (NE), as the main neurotransmitter. Complementarily, T and B lymphocytes express β2-adrenergic receptors, while innate immune cells express both α- and β-adrenergic receptors. The consequences of adrenergic receptor signaling can be summarized as immuno-modulatory. Activation of adrenergic receptors leads to decreased levels of pro-inflammatory cytokines (e.g. IL-1β, IL-6, TNF-α) and increased levels of anti-inflammatory cytokines, like IL-10 or TGF-β. Cellular changes include increase in the number of regulatory T cells and shift of the Th1/Th2 balance towards the Th2 response. Since the changes in immune response are global, the explanation has to include generalization of the SGB effect. A likely explanation includes centripetal neuronal pathways between the stellate ganglion and deep brain regions such as insula, amygdala, and hippocampus. Those, in turn, have reciprocal innervation with locus ceruleus, a brain-stem structure involved in the control of the autonomous nervous system. ConclusionVarious pathologic conditions have been shown to be SGB responsive, where the symptoms have been reduced or eliminated. Many of those clinical improvements have been mirrored by measurable immunologic changes. A plausible explanation, consistent with the evidence available so far, is that SGB exerts its effects by regulating the immune system, through a central, reflex-like pathway. Our hypothesis provides a theoretical framework for understanding the effects of SGB and could, thus lead to wider usage of the technique in immune-linked disorders such as ulcerative colitis.

Thoracoscopic delivery of therapeutics in the swine sympathetic chain: Implications for future neuromodulation

The thoracic sympathetic chain is implicated in several disease processes including palmar hyperhidrosis and complex regional pain syndrome. These diseases are often medically refractory and require surgical treatments including sympathectomies and ganglion blocks. The use of chemogenetic or optogenetic technologies to modulate sympathetic chain activity may be a potential treatment for these diseases. However, there is no established thoracoscopic surgical approach to deliver viral vectors into the thoracic sympathetic chain and ganglia. Our objective was to evaluate the feasibility of thoracoscopic injection of the swine sympathetic chain. Two Landrace farm pigs underwent a novel procedure for thoracoscopic sympathetic chain injections. One was non-survival and one was a five-day survival surgery. Both procedures successfully delivered methylene blue in the thoracic sympathetic chain. Over the five-day postoperative period, the animal displayed stable vital signs. Thoracoscopic targeted injections of the sympathetic chain is a feasible approach to deliver therapeutics in swine. Future studies should investigate the use of transgene expression as a potential means to control sympathetic output for the development of novel therapies for palmar or axillary hyperhidrosis, thoracic neuropathic pain syndromes and select peripheral vascular diseases.

Structure of sympathetic input to interscapular brown adipose tissue in the mouse

Interscapular brown adipose tissue (iBAT) is under sympathetic and sensory nerve control. We recently identified the stellate and thoracic sympathetic chain ganglia T1‐T5 as the main origins of sympathetic input to iBAT in adult male and female mice. Previous studies reported that iBAT receives sympathetic innervation from five intercostal nerves; even though intercostal nerves (which originate from ventral rami) are typically known to provide innervation to lateral, ventral body tissues. Furthermore, we were unable to find literature with detailed anatomical studies. Here, we used a reporter mouse model that expresses tdTomato in tyrosine hydroxylase expressing neurons (TH‐tomato mice) in all sympathetic nerve fibers to facilitate dissection and imaging of sympathetic nerves to iBAT. Our data clarifies that iBAT receives sympathetic input via dorsal rami, which combine sensory and sympathetic fibers. This is consistent with the role of dorsal rami to innervate dorsal body structures, while intercostal nerves (traveling along the ribs) provide innervation to lateral and ventral body structures in mammals. Furthermore, we performed whole mount and paraffin embedded anatomical studies of TH (as surrogate for sympathetic nerves) to understand the anatomy and structure of sympathetic iBAT innervation. We found that fine sympathetic nerve fibers branch off the dorsal rami emanating from T1‐T4 to enter the BAT pad, and from there further branch to form axonal varicosities. Meanwhile, the dorsal rami continue to innervate vasculature and skin. We further established a novel tool to quantify axonal varicosities across entire adipose tissue depots using the IMARIS spot detection tool. This allowed us to visualize the extensive variation of axonal varicose density within the entire iBAT depot with dense varicosities adjacent to brown adipocytes, but sparse varicosities adjacent to white adipocytes. We also analyzed the axonal varicosities in inguinal white adipose tissue and found denser varicosities associated with beige islands that were significantly increased after 7day cold exposure (10°C). Finally, we use UCP1‐reporter mice and whole mount iBAT staining of TH to verify that dense axonal varicosities overlap with UCP1‐positive tissue, while UCP1‐negative tissue shows sparse axonal varicosities. The dynamic and anatomically distinct regulation of sympathetic axonal varicose density is likely due to distinct neurotrophic interaction of brown and white adipocytes with sympathetic neurons. Our data clarify the structure of sympathetic innervation to the iBAT in the mouse and highlights the benefits to study endorgans like entire adipose depots in an anatomically defined manner.Support or Funding InformationGrant support: NIH 4OT2 OD23864‐01

Ultrasound tour of the anterior neck for the interventional pain physician

Ultrasound tour of the anterior neck for the interventional pain physician

C-Arm Guided Percutaneous Radiofrequency Thoracic Sympathectomy for Treatment of Primary Palmar Hyperhidrosis in Comparison with Local Botulinum Toxin Type A Injection, Randomized Trial

Background: Hyperhidrosis is a disorder associated with detrimental effects on patients’ quality of life, occupational activities, and social interactions. Objectives: This study compares C-arm guided percutaneous radiofrequency (RF) ablation of the second and third thoracic sympathetic ganglions and local intradermal botulinum toxin type A (BTX-A) injection for the treatment of primary palmar hyperhidrosis. It focuses on clinical effectiveness, patient satisfaction, quality of life, safety, and the time at which repetition of the procedure is needed over one-year follow-up. Study Design: This is a randomized single-blinded trial. Setting: This study took place in a single hospital. Methods: Eighty patients with primary palmar hyperhidrosis were randomly assigned to one of 2 interventions: local intradermal BTX-A injection (n = 40) or C-arm guided percutaneous RF ablation (n = 40). The Dermatology Life Quality Index (DLQI) questionnaire and the Hyperhidrosis Disease Severity Scale (HDSS) were used for assessment at one week, one month, and 2, 6, and 12 months after intervention. The number of patients who required repetition of the procedure later on and the time at which they needed it were recorded, and possible side effects were assessed. Results: HDSS scores in the RF group were statistically significantly lower than in the BTX-A group at one week, one month, and 2, 6, and 12 months of follow-up. DLQI scores in the RF group were statistically significantly lower than in the BTX-A group at 6- and 12-month follow-up, whereas at one week, one month, and 2 months of follow-up, there was no statistically significant difference between both groups. The number of patients who required that the procedure be repeated was statistically significantly lower in the RF group than in the BTX-A group. The time at which patients needed repetition of the procedure in the BTX-A group was about 3 to 7 months after the first intervention. All patients in this group showed an increase in HDSS scores within this one-year followup. In the RF group, however, only one patient complained of increased HDSS scores after 8 months. There was no statistically significant difference in side effects between both groups. Limitations: The first limitation of this study is that results were based on subjective scales. The second is the radiation exposure associated with the technique described. Conclusions: This study supports percutaneous C-arm guided RF ablation of the second and third thoracic sympathetic ganglions and local intradermal BTX-A injection as safe, effective options and rapid lines of treatment of primary palmar hyperhidrosis. However, percutaneous RF ablation proved to be more effective, with longer effectiveness time and better patient satisfaction, compared to local intradermal BTX-A injection.