Frequency of visualization of presumed celiac ganglia by endoscopic ultrasound

Endoscopic Ultrasound-Guided Pain Management

The diagnosis and management of pancreatic cancer has become a standard role for the endoscopic oncologist. Pancreatic cancer can produce disabling abdominal pain, and the medical management of this pain is often challenging. Endoscopic ultrasound-guided celiac plexus neurolysis and celiac ganglia neurolysis serve as an alternative or adjunct for pain control in these patients. There remains a great deal of practice variability with regard to techniques and approaches. This article summarizes the latest scientific evidence and highlights contemporary best practice advice for these procedures.

EUS-guided celiac plexus neurolysis for pancreas cancer - Finally established or still under review?

Patients with pancreas cancer must deal frequently with intractable and refractory pain. Endoscopic ultrasound guided-celiac plexus neurolysis (EUS-CPN) has been the most studied and used therapeutic technique aimed to destroy the pain fibres that allow the pancreas to communicate with the central nervous system. A neurolytic agent, most commonly ethanol, is optimally spread around the celiac axis in order to reduce pain and mitigate narcotic requirements. This can be performed early to prevent the spiral of pain and medication use, or more historically as salvage therapy. Different techniques to best administer the ethanol for effective EUS-CPN are still being debated. New EUS-guided injection techniques with radiofrequency, radioactive, and/or chemotherapeutic agents need more study.

EUS-CGN versus EUS-CPN in pancreatic cancer: A qualitative systematic review

BACKGROUND

Comparison between endosonographic ultrasonography (EUS)-guided celiac ganglia neurolysis (CGN) and EUS-guided celiac plexus neurolysis (CPN) in pain management for pancreatic cancer has engendered controversy. To analyze the effectiveness and safety of EUS-CGN and figure out whether EUS-CGN is better than EUS-CPN, a qualitative systematic review was conducted.

METHODS

Studies were searched from Cochrane Central Register of Controlled Trials, MEDLINE, and EMBASE up to April 2020. We only included studies with full-text and in English and assessed study quality with Newcastle-Ottawa Scale or Cochrane risk-of-bias tool. We recorded details of study design, participants, procedure performed, protocol of follow-up, pain response, quality of life, survival, and adverse events. The study was conducted under Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement 2009.

RESULTS

Five studies involving 319 patients were included. Short-term pain response rates ranged from 65.0% to 88.46% in EUS-CGN group and most studies reported its superiority over EUS-CPN. As for adverse events, the incidence of transient hypotension and gastrointestinal symptoms seemed comparable, while results of initial pain exacerbation varied among studies. Besides, EUS-CGN might provide a shorter survival.

CONCLUSION

EUS-CGN can be safely performed while it may shorten survival. In terms of short-term pain response, EUS-CGN is better than EUS-CPN while no conclusion of long-term pain control can be drawn.

Accuracy of Endoscopic Ultrasound Imaging in Distinguishing Celiac Ganglia From Celiac Lymph Nodes

BACKGROUND & AIMS

Endoscopic ultrasound (EUS) allows visualization of celiac lymph nodes (CLNs) and celiac ganglia (CG). Reliably distinguishing these structures is important for tumor staging and CG ablative therapies. We aimed to evaluate the accuracy of EUS in distinguishing CLNs from CG using a strict cytopathology reference standard. We also determined the rate of detection of CLN and CG by conventional cross-sectional imaging.

METHODS

From EUS and cytopathology databases, we identified all patients who underwent EUS-FNA of a presumed CLN or CG from October 1, 2004, through March 1, 2017, and compared the findings with those from cytology (reference standard). Indeterminate cytology results were re-reviewed. EUS imaging (ie, index test) results were compared with those from the reference standard. An expert radiologist re-reviewed computed tomography and magnetic resonance images from 100 lesions, from 94 randomly selected patients with a reference standard, to determine the rates of CLN and CG detection.

RESULTS

A total of 504 patients (mean age, 63.4 ± 13.2 years; 292 men) underwent a median of 7 EUS-FNA passes (range, 1-13) for a total of 566 lesions perceived to be either a CLN or CG; the cytology reference standard was available for 521 lesions (92.1%). When we excluded indeterminate cytology results, the EUS accurately identified 281/286 CLNs (98.3%) and 166/186 CGs (89.2%), for an overall accuracy of 447/472 (94.7%). EUS-FNA distinguished CG from CLNs with a 93.3% sensitivity, 93.7% specificity, a positive predictive value of 96.2%, and a negative predictive value of 89.2%. Of 100 lesions in 94 patients randomly selected for a second expert radiology review, computed tomography and magnetic resonance imaging detected 59/67 CLNs (88.1%) and 13/33 CG (39.4%).

CONCLUSION

EUS accurately distinguishes CLNs from CG. EUS might therefore be used to increase the accuracy of tumor staging, to select tumor stage-appropriate therapy, and to guide CG-ablative therapies.

Alleviating Pancreatic Cancer-Associated Pain Using Endoscopic Ultrasound-Guided Neurolysis

The most common symptom in patients with advanced pancreatic cancer is abdominal pain. This has traditionally been treated with nonsteroidal anti-inflammatory drugs and opioid analgesics. However, these treatments result in inadequate pain control or drug-related adverse effects in some patients. An alternative pain-relief modality is celiac plexus neurolysis, in which the celiac plexus is chemically ablated. This procedure was performed percutaneously or intraoperatively until 1996, when endoscopic ultrasound (EUS)-guided celiac plexus neurolysis was first described. In this transgastric anterior approach, a neurolytic agent is injected around the celiac trunk under EUS guidance. The procedure gained popularity as a minimally invasive approach and is currently widely used to treat pancreatic cancer-associated pain. We focus on two relatively new techniques of EUS-guided neurolysis: EUS-guided celiac ganglia neurolysis and EUS-guided broad plexus neurolysis, which have been developed to improve efficacy. Although the techniques are safe and effective in general, some serious adverse events including ischemic and infectious complications have been reported as the procedure has gained widespread popularity. We summarize reported clinical outcomes of EUS-guided neurolysis in pancreatic cancer (from the PubMed and Embase databases) with a goal of providing information useful in developing strategies for pancreatic cancer-associated pain alleviation.

Celiac Plexus Block and Neurolysis in the Management of Chronic Upper Abdominal Pain

Chronic upper abdominal pain occurs as a complication of various malignant and benign diseases including pancreatic cancer and chronic pancreatitis, and when present may contribute to lower quality of life and higher mortality. Though various pain management strategies are available as part of a multimodal approach, they are often incompletely effective and accompanied by side effects. Pain originating in upper abdominal viscera is transmitted through the celiac plexus, which is an autonomic plexus located in the retroperitoneum at the root of the celiac trunk. Direct intervention at the level of the plexus, referred to as celiac plexus block or neurolysis depending on the injectate, is a minimally invasive therapeutic strategy which has been demonstrated to decrease pain, improve function, and reduce opiate dependence. Various percutaneous techniques have been reported, but, with appropriate preprocedural planning, use of image guidance (usually computed tomography), and postprocedural care, the frequency and severity of complications is low and the success rate high regardless of approach. The main benefit of the intervention may be in reduced opiate dependence and opiate-associated side effects, which in turn improves quality of life. Celiac plexus block and neurolysis are safe and effective treatments for chronic upper abdominal pain and should be considered early in patients experiencing such symptoms.

EUS-guided celiac ganglia neurolysis: a clinical and human cadaver study (with video)

BACKGROUND AND AIMS

There is little evidence that structures targeted during EUS-guided celiac ganglia neurolysis (EUS-CGN) are celiac ganglia and that selective ethanol injection into ganglia is feasible. We aimed to visualize celiac ganglia, confirm that these structures are ganglia, and visualize ethanol spread after EUS-CGN and EUS-guided celiac plexus neurolysis (EUS-CPN).

METHODS

First, celiac ganglia were sought during 97 consecutive EUS procedures. Second, ganglia were identified in a prosected human cadaver by placing a linear echoendoscope next to the celiac trunk and removing the underlying tissue for histology. Finally, various EUS-CGN and EUS-CPN techniques were performed in human cadavers; EUS-CGN was performed with 1 mL ethanol in 1 ganglion, 1 mL per ganglion (both low volume), and 4 mL per ganglion (high volume). EUS-CPN was performed with a central (20 mL) and a bilateral (2*10 mL) approach. Transverse sections (75 μm) were obtained and photographed to allow visualization of the spread of ethanol.

RESULTS

A total of 204 ganglia were detected in 83 patients. Mean (± standard deviation) size of the long axis was 8.1 mm (± 7.4 mm). Histology of the removed region in the cadaver showed only nerve cell bodies. After low-volume EUS-CGN in cadavers, ethanol spread well beyond the targeted ganglion. After high-volume EUS-CGN in cadavers, a larger ethanol spread was seen, which also reached unidentified ganglia; the spread was comparable to the spread after EUS-CPN.

CONCLUSIONS

Specific EUS-CGN is not feasible because ethanol spreads well beyond the targeted ganglion. Unidentified celiac ganglia are better reached with high-volume EUS-CGN, and this would likely result in a more thorough neurolysis. High-volume EUS-CGN should be preferred to low-volume EUS-CGN.

Recent Advances in Therapeutic Endosonography for Cancer Treatment

Therapeutic endosonography (EUS) may play an important role in the management of cancers. EUS-guided fiducial placement has a high success rate and can aid in stereotactic radiotherapy. EUS-guided tumor ablation therapies can help in palliation of locally advanced tumors. EUS-guided antitumor injection seems to be feasible and safe in animals; initial human studies suffer from small sample size and lack of controls. Randomized, controlled trials have not shown benefit over conventional therapy. EUS celiac plexus neurolysis has gained popularity and is performed by interventional endosonographers. Large trials are needed to determine the most appropriate indications and overall usefulness of these therapies.

A case of pancreatic cancer with severe vomiting treated by endoscopic ultrasound-guided celiac ganglia neurolysis

A 50-year-old man with advanced pancreatic cancer was admitted for intractable severe vomiting 5-6 times a day, continuing over a week. He had been treated for advanced pancreatic cancer with chemotherapy for 6 months, and had undergone self-expandable metalic stent placement for obstructive jaundice due to the pancreatic cancer 4 months before admission. No abnormal findings suggesting gastrointestinal obstruction or brain metastasis were revealed on diagnostic imaging. We performed endoscopic ultrasound-guided celiac ganglia neurolysis twice by injecting ethanol into the celiac ganglion. After the treatments, the vomiting disappeared, and his eating habits gradually returned to normal. The patient died 7 months after treatment due to the advanced pancreatic cancer without recurrence of the vomiting.

Evaluation of outcomes of ultrasound guided celiac plexus neurolysis using immediate post procedure computed tomography: An observational study

BACKGROUND

An interventional procedure like celiac plexus neurolysis (CPN) has a significant role in relieving intractable pain in patients with locally advanced abdominal malignancies. Ultrasound (USG) guidance enables performance of bedside CPN by real-time visualization of the needle trajectory. The objective of the study was to perform percutaneous USG-guided CPN and to verify technical outcomes of the procedure using a post-procedure CT scan.

METHODS

Eleven eligible patients of advanced upper abdominal malignancies having a pain score of >3/10 on visual analog scale (VAS) were recruited to undergo CPN. A post-procedure CT scan was performed to evaluate technical outcomes of the procedure. Patients were evaluated for pain relief. They were followed up at the 1st, 4th, and 6th weeks after CPN.

RESULTS

Eleven patients underwent USG-guided CPN. The injected drug was visualized as an echogenic cloud in ultrasound in 7 out of 11 (64%) patients. In the remaining 4 patients, the echogenic cloud was not well formed. In the post-procedure CT scan, the spread of the drug was seen in all 11 patients. This spread was bilaterally symmetrical in 7 (64%) patients and asymmetrical or unilateral in 4 (36%) patients. All patients in the immediate post-procedure period and 91% of the patients during the 1st-, 4th-, and 6th-week follow up had improvement in their pain scores.

CONCLUSION

A post-procedure CT scan was useful in verifying the technical outcome of USG-guided CPN in patients with advanced upper abdominal malignancies.

Practice guidelines for endoscopic ultrasound-guided celiac plexus neurolysis

Objectives:

The objective of guideline was to provide clear and relevant consensus statements to form a practical guideline for clinicians on the indications, optimal technique, safety and efficacy of endoscopic ultrasound guided celiac plexus neurolysis (EUS-CPN).

Methods:

Six important clinical questions were determined regarding EUS-CPN. Following a detailed literature review, 6 statements were proposed attempting to answer those questions. A group of expert endosonographers convened in Chicago, United States (May 2016), where the statements were presented and feedback provided. Subsequently a consensus group of 35 expert endosonographers voted based on their individual level of agreement. A strong recommendation required 80% voter agreement. The modified GRADE (Grading of Recommendations Assessment, Development, and Evaluation) criteria were used to rate the strength of recommendations and the quality of evidence.

Results:

Eighty percent agreement was reached on 5 of 6 consensus statements, 79.4% agreement was reached on the remaining one.

Conclusions:

EUS-CPN is efficacious, should be integrated into the management of pancreas cancer pain, and can be considered early at the time of diagnosis of inoperable disease. Techniques may still vary based on operator experience. Serious complications exist, but are rare.

Predictors of pain response in patients undergoing endoscopic ultrasound-guided neurolysis for abdominal pain caused by pancreatic cancer

BACKGROUND

Interventional endoscopic ultrasound (EUS)-guided procedures such as EUS-guided celiac ganglia neurolysis (EUS-CGN) and EUS-guided broad plexus neurolysis (EUS-BPN) were developed to treat abdominal cancer-associated pain; however, these procedures are not always effective. The aim of this study was to explore predictors of pain response in EUS-guided neurolysis for pancreatic cancer-associated pain.

METHODS

This was a retrospective analysis of prospectively collected data of 112 consecutive patients who underwent EUS-BPN in our institution. EUS-CGN was added in cases of visible celiac ganglia. The neurolytic-spread area was divided into six sections and evaluated by post-procedural computed tomography scanning. Pain intensity was assessed using a visual analog scale (VAS), and a decrease in VAS scores by ⩾3 points after neurolysis was considered a good pain response. Univariable and multivariable logistic regression analyses were performed to explore predictors of pain response at 1 and 4 weeks, and complications.

RESULTS

A good pain response was obtained in 77.7% and 67.9% of patients at 1 and 4 weeks, respectively. In the multivariable analysis of these patients, the combination method (EUS-BPN plus CGN) was a significant positive predictive factor at 1 week (odds ratio = 3.69, p = 0.017) and 4 weeks (odds ratio = 6.37, p = 0.043). The numbers of neurolytic/contrast spread areas (mean ± SD) were 4.98 ± 1.08 and 4.15 ± 1.12 in patients treated with the combination method and single method, respectively (p < 0.001). There was no significant predictor of complications.

CONCLUSIONS

EUS-BPN in combination with EUS-CGN was a predictor of a good pain response in EUS-guided neurolysis for pancreatic cancer-related pain. The larger number of neurolytic/contrast spread areas may lead to better outcomes in patients receiving combination treatment.

Frequency and characterization of celiac ganglia diagnosed on fine-needle aspiration

INTRODUCTION

Endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA) is frequently used to sample intra-abdominal lesions and lymph nodes. Celiac ganglia normally located near the celiac artery may be sampled during these procedures. The aim of this study was to determine the frequency of detection and cytologic findings of celiac ganglia diagnosed on FNA.

MATERIALS AND METHODS

A 14-year retrospective review of radiologic and endoscopic FNA cases involving the celiac region was performed. Cases in which ganglia were reported were further analyzed and slides reviewed.

RESULTS

A total of 354 patients underwent FNA of a suspected celiac lymph node (334 patients) or celiac mass (20 cases). In 9 of these patients (2.5%), ganglion cells were identified. These were identified in cases only after 2008 via EUS-guided FNA. Aspirates were hypocellular and bloody. Large ganglion cells were either sparsely dispersed or present in clusters. Ganglion cells had a low N: C ratio, granular cytoplasm with neuromelanin, and eccentric small round nucleus with a prominent nucleolus. One specimen had concomitant pancreatic adenocarcinoma. None of these cases had a false positive on-site adequacy assessment or final misdiagnosis.

CONCLUSIONS

These data show that celiac ganglia may be infrequently encountered, especially with intra-abdominal EUS-guided FNA targeting nodes or masses near the celiac region. Therefore, cytologists should be aware of the possibility of finding ganglionic cells in EUS-guided FNA samples.

EUS-guided celiac plexus interventions in pancreatic cancer pain: An update and controversies for the endosonographer

Patients with pancreatic cancer (pancreatic ductal adenocarcinoma [PDAC]) can develop abdominal pain that can be debilitating. Celiac plexus neurolysis (CPN) is a chemical ablation of the celiac plexus that can be used to treat pain caused by pancreatic malignancy. It can be performed by an anterior or posterior approach, and also can be done percutaneously or under guidance of transabdominal ultrasound, computed tomography, intra-operatively or most recently under linear endoscopic ultrasound (EUS) guidance (EUS-CPN). EUS is well-suited for identification of the celiac plexus due to the close proximity of the gastric wall to the origin of the celiac artery. EUS-CPN is now widely practiced, and different EUS approaches have been developed in order to improve the efficacy of this technique. Our objective is to review the use of EUS-CPN in PDAC, including a description of different techniques, review of its efficacy, predictors of pain response, and describe its limitations and safety, as well as new developments.

Celiac plexus neurolysis in the management of unresectable pancreatic cancer: When and how?

Pancreatic cancer is the second most common abdominal cancer in North America with an estimated 20% resectability at diagnosis, and overall 5-year survival of 5%. Pain is common in pancreatic cancer patients with 70%-80% suffering substantial pain. Celiac plexus neurolysis (CPN) is a technique that can potentially improve pain control in pancreatic cancer while preventing further escalation of opioid consumption. CPN is performed by injecting absolute alcohol into the celiac plexus neural network of ganglia. This review sets out to explore the current status of CPN in non-resectable pancreatic cancer. We will examine: (1) the efficacy and safety of percutaneous-CPN and endoscopic ultrasound guided-CPN; (2) specific technique modifications including bilateral (vs central) injections and celiac ganglia neurolysis; and (3) the issue of CPN timing, early at pancreatic cancer diagnosis vs traditional late use as salvage therapy.

Celiac plexus neurolysis in pancreatic cancer: the endoscopic ultrasound approach

Pain in pancreatic cancer is often a major problem of treatment. Administration of opioids is frequently limited by side effects or insufficient analgesia. Endoscopic ultrasound-guided celiac plexus neurolysis (EUS-CPN) represents an alternative for the palliative treatment of visceral pain in patients with pancreatic cancer. This review focuses on the indications, technique, outcomes of EUS-CPN and predictors of pain relief. EUS-CPN should be considered as the adjunct method to standard pain management. It moderately reduces pain in pancreatic cancer, without eliminating it. Nearly all patients need to continue opioid use, often at a constant dose. The effect on quality of life is controversial and survival is not influenced. The approach could be done in the central position of the celiac axis, which is easy to perform, or in the bilateral position of the celiac axis, with similar results in terms of pain alleviation. The EUS-CPN with multiple intraganglia injection approach seems to have better results, although extended studies are still needed. Further trials are required to enable more confident conclusions regarding timing, quantity of alcohol injected and the method of choice. Severe complications have rarely been reported, and great care should be taken in choosing the site of alcohol injection.

Endoscopic ultrasound-guided fine needle aspiration of the celiac ganglion: A diagnostic pitfall

Endoscopic ultrasound guided fine-needle aspiration (EUS-FNA) is now widely used as a primary tool in the evaluation of lymphadenopathy in both the mediastinum and abdomen. A sympathetic ganglion may be mistaken for an enlarged lymph node on endoscopic ultrasound and are rarely sampled as such. A 51-year-old female presented with a history of weight loss, vomiting for several months, and right upper quadrant discomfort. Computed tomography (CT) and magnetic resonance imaging (MRI) scans showed a dilated common bile duct (CBD) with a possible periampullary mass, paraaortic, and pericelial lymph nodes suspicious for metastatic disease. Endosonography revealed a 17 mm oval hypoechoic structure with distinct margins in the para-aortic, celiac axis region suggestive of an enlarged lymph node. An EUS-FNA was done. Cytology revealed ganglion cells with large oval epithelial-like cells with round nuclei and prominent nucleoli consistent with a benign sympathetic ganglion. It is crucial for the cytopathologist to be aware of the fact that the endoscopist might have sampled a celiac ganglion instead of a celiac lymph node and be able to distinguish the cytological features of a benign sympathetic ganglion from a malignant process.

Endoscopic ultrasound-guided celiac neurolysis

Intractable abdominal pain commonly develops in patients with pancreatic cancer. Oral pharmacologic therapy is ineffective for many patients and side effects commonly occur. Celiac neurolysis (CN) is sometimes performed to enhance pain relief. Percutaneous approaches were initially described, with endoscopic ultrasound (EUS)-guided CN more recently introduced. There is uncertainty regarding the efficacy and role of CN in managing pancreatic cancer pain, but CN should still be considered in this difficult-to-treat cohort of patients. EUS-guided approaches may be favored when EUS is otherwise indicated for diagnostic or staging purposes. When EUS is not otherwise indicated, percutaneous approaches are likely favored.

Endoscopic therapy in chronic pancreatitis

Chronic pancreatitis (CP) is a debilitating disease that can result in chronic abdominal pain, malnutrition, and other related complications. The main aims of treatment are to control symptoms, prevent disease progression, and correct any complications. A multidisciplinary approach involving medical, endoscopic, and surgical therapy is important. Endoscopic therapy plays a specific role in carefully selected patients as primary interventional therapy when medical measures fail or in patients who are not suitable for surgery. Endoscopic therapy is also used as a bridge to surgery or as a means to assess the potential response to pancreatic surgery. This review addresses the role of endoscopic therapy in relief of obstruction of the pancreatic duct (PD) and bile du ct, closure of PD leaks, and drainage of pseudocysts in CP. The role of endoscopic ultrasound-guided celiac plexus block for pain in chronic pancreatitis is also discussed.

Endoscopic ultrasound-guided neurolysis in pancreatic cancer

Abdominal pain in patients with pancreatic cancer is a common symptom that is often difficult to manage. Opioids are frequently used in an attempt to mitigate pain; however, side effects may develop. Celiac plexus neurolysis (CPN) affords effective pain control in patients with pancreatic cancer and is not associated with opioid side effects. Endoscopic ultrasound (EUS)-guided CPN has demonstrated safety and efficacy due to real-time imaging and anterior access to the celiac plexus from the posterior gastric wall, thereby avoiding complications related to the puncture of spinal nerves, arteries and the diaphragm, and is now practiced widely. Furthermore, two new techniques of EUS-guided neurolysis for abdominal pain management in pancreatic cancer patients have recently been developed. The first technique is EUS-guided celiac ganglia neurolysis (EUS-CGN) in which EUS facilitates CGN by enabling direct injection into the individual celiac ganglion, and the second technique is EUS-guided broad plexus neurolysis (EUS-BPN) which extends over the superior mesenteric artery. This review provides evidence for the efficacy of EUS-CPN. Particular attention is paid to the two new techniques of EUS-guided neurolysis, EUS-CGN and EUS-BPN.

Endoscopic ultrasound-guided celiac plexus neurolysis

Endoscopic celiac plexus neurolysis (CPN) has become the procedure of choice for the management of patients with pancreatic cancer and abdominal pain unresponsive to medical treatment. It is necessary to differentiate between CPN and endoscopic celiac plexus block performed in patients with benign disease. In this review we describe the technique of this procedure with special emphasis on technical details.

Endoscopic treatment in chronic pancreatitis, timing, duration and type of intervention

Endoscopic treatment of chronic pancreatitis (CP) aims to relieve pain by draining the main pancreatic duct (MPD) and to treat loco-regional complications. Half of patients have complete pain relief five years after treatment, with best results obtained if treatment is performed early after the first pain attack. If MPD obstruction is caused by calcifications, ambulatory extracorporeal shock wave lithotripsy has become a first-line treatment (9-30% of patients require ERCP during follow-up). If MPD obstruction is caused by stricture(s), insertion of single plastic stent is effective but it requires multiple ERCPs for stent exchanges; other protocols are being investigated. Pseudocysts represent an excellent indication for endoscopic treatment with long-term results similar to those of surgery; endosonography-guided techniques allow treatment of almost any pancreatic pseudocyst. Biliary strictures related to CP are challenging due to a high relapse rate and requirement for multiple ERCP sessions. Significant progress has recently been made with new protocols of temporary biliary stenting (multiple simultaneous plastic stents or covered metallic stents).

Endoscopic ultrasound-guided celiac plexus neurolysis using a reverse phase polymer

AIM: To assess the feasibility of endoscopic ultrasound (EUS)-guided celiac plexus neurolysis (CPN) using a poloxamer.

METHODS: In this prospective evaluation, six Yorkshire pigs underwent EUS-guided CPN. Three received an injection of 10 mL of 0.25% Lidocaine plus methylene blue (group 1) and three received an injection of 10 mL of 0.25% Lidocaine plus blue colored poloxamer (PS137-25) (group 2). Necropsy was performed immediately after the animals were sacrificed. The abdominal and pelvic cavities were examined for the presence of methylene blue and the blue colored poloxamer.

RESULTS: EUS-guided CPN was successfully performed in all 6 pigs without immediate complication. Methylene blue was identified throughout the peritoneal and retroperitoneal cavity in group 1. The blue colored poloxamer was found in the retroperitoneal cavity immediately adjacent to the aorta, in the exact location of the celiac plexus in group 2.

CONCLUSION: EUS-guided CPN using a reverse phase polymer in a non-survival porcine model was technically feasible. The presence of a poloxamer gel at the site of the celiac plexus at necropsy indicates a precise delivery of the neurolytic agent.

Interventional endoscopic ultrasound: Therapeutic capability and potential

The linear echoendoscope, introduced in the 1990s, opened the era of interventional endoscopic ultrasound (IEUS). The linear echoendoscope enabled EUS guided Fine Needle Aspiration (EUS-FNA) allowing the path of the needle to be traced during the puncture process. After EUS-FNA, other interventional procedures were introduced in clinical practice. Tissue acquisition was the first EUS-guided interventional procedure and its higher diagnostic quality has undoubtedly been established. After EUS-FNA, Celiac plexus neurolysis (CPN) and block (CPB), pancreatic pseudocyst drainage, abdominal and mediastinal collections/abscesses drainage, and in selected cases, pancreatic and biliary ductal system drainage, were introduced in clinical practice. EUS-guided fine needle injection with local delivery of antitumor agents is considered a promising modality. We have reviewed published data on EUS guided interventional procedures with the object of summarizing the diagnostic capability of endoscopic ultrasound and elaborates in detail its therapeutic capability and potential.

Coeliac plexus neurolysis

Coeliac plexus neurolysis (CPN) has been performed for nearly 100 years to try and control pancreatic pain. In recent years endoscopic ultrasound (EUS)-guided CPN has become the preferred technique for this procedure yet relatively little data exists to support its superiority over other methods. Recent studies have demonstrated the potential for direct EUS-guided injection into coeliac ganglia as a means to improve efficacy of CPN. This article describes the technique of EUS-CPN, the evidence supporting its use and recent advances in this procedure.

Interventional EUS for the treatment of pancreatic cancer

Since the curved linear array echoendoscope (linear EUS) was developed in the 1990s, EUS has evolved from EUS imaging, to EUS-guided FNA, and now to EUS-guided fine needle injection (FNI), giving EUS even wider application. This advancement has brought "interventional EUS" into the pancreato-biliary field. Interventional EUS for pancreatic cancer includes delivery of contrast agents, drainage/anastomosis, celiac neurolysis (including ganglion neorolysis), radiofrequency ablation, photodynamic therapy, brachytherapy, and delivery of a growing number of anti-tumor agents. This review will focus on interventional EUS in the treatment of pancreatic cancer.

Endoscopic therapy for chronic pancreatitis: technical success, clinical outcomes, and complications

Chronic pancreatitis (CP) can cause failure of both the exocrine and endocrine portions of the gland. Pain is the most recalcitrant clinical complaint in CP. Generally, conservative measures are first attempted to manage pain. These include cessation of alcohol use and smoking, enzyme replacement therapy, and finally, opioid analgesia. Endoscopy can be employed to treat the pain and complications due to CP. The results of the only two prospective randomized controlled trials suggest that surgery has a more durable effect than endoscopic therapy in controlling pain. Both trials suffer from severe limitations, however, and endoscopy remains the preferred approach for many patients because of its minimally invasive nature. Endoscopic ultrasound celiac plexus block has limited value in helping to control pain. More randomized trials are needed, along with further technologic innovation to improve the current treatment modalities. When considering interventional therapy for a patient with CP, a tailored and multidisciplinary therapeutic approach should be taken.

Interventional endoscopic ultrasonography

Endoscopic ultrasonography (EUS) is the combination of endoscopy and intraluminal ultrasonography. This allows use of a high frequency transducer, which, due to the short distance to the target lesion, enables ultrasonographic images of high resolution to be obtained. Endoscopic ultrasonography is now a widely accepted modality for the diagnosis of pancreatobiliary diseases. It can be used to determine the depth of invasion of gastrointestinal malignancies, and often for visualizing lesions more precisely than other imaging modalities. The most important early limitation of EUS was the lack of specificity in the differentiation between benign and malignant changes. In 1992, EUS-guided fine needle aspiration (EUS-FNA) of lesions in the pancreas head has been made possible using a curved linear array echoendoscope. Since then, many researchers have expanded the indication of EUS-FNA to various kinds of lesions and also for a variety of therapeutic purposes. In this review, we particularly focus on the present and future roles of interventional EUS, including EUS-FNA and therapeutic EUS.

Initial evaluation of the efficacy and safety of endoscopic ultrasound-guided direct Ganglia neurolysis and block

BACKGROUND

Celiac plexus neurolysis and block are considered safe but provide limited pain relief. Standard techniques target the region of the celiac plexus but do not attempt injections directly into celiac ganglia. The recent recognition that celiac ganglia can be visualized by endoscopic ultrasound (EUS) now allows direct injection into celiac ganglia for neurolysis (CGN) and block (CGB).

AIMS

To determine the safety and initial efficacy (at 2-4 wk) of direct ganglia injection in patients with moderate to severe pain secondary to unresectable pancreatic carcinoma or chronic pancreatitis.

METHODS

An EUS database was reviewed to identify patients undergoing CGN and CGB. Data were retrieved from the medical records and phone follow-up.

RESULTS

Thirty-three patients underwent 36 direct celiac ganglia injections for unresectable pancreatic cancer (CGN N = 17, CGB N = 1) or chronic pancreatitis (CGN N = 5, CGB N = 13) with bupivacaine (0.25%) and alcohol (99%) for CGN, or Depo-Medrol (80 mg/2 cc) for CGB. Cancer patients reported pain relief in 16/17 (94%) when alcohol was injected and 0/1 (00%) when steroid was injected. For chronic pancreatitis, 4/5 (80%) who received alcohol reported pain relief versus 5/13 (38%) receiving steroids. Thirteen (34%) patients experienced initial pain exacerbation, which correlated with improved therapeutic response (P < 0.05). Transient hypotension and diarrhea developed in 12 and 6 patients, respectively.

CONCLUSIONS

Initial experience suggests that EUS-guided direct celiac ganglion block or neurolysis is safe. Alcohol injection into ganglia appears to be effective in both cancer and chronic pancreatitis. Prospective trials are needed to confirm the efficacy of this new approach.