Endoscopic injection of botulinum toxin in patients with recurrent acute pancreatitis due to pancreatic sphincter of Oddi dysfunction

Protocol of a randomised controlled phase II clinical trial investigating PREoperative endoscopic injection of BOTulinum toxin into the sphincter of Oddi to reduce bile leakage after hepatic resection: the PREBOT-II trial

INTRODUCTION

Bile leakage represents a major cause of morbidity following hepatic resection. Although most patients can be managed non-operatively, this complication requires diagnostics and therapeutic interventions. Preoperative endoscopic injection of botulinum toxin (BTX) into the sphincter of Oddi represents an innovative approach to prevent bile leakage. The aim of the PREBOT-II trial is to generate the first randomised controlled trial data on the safety, feasibility and efficacy of preoperative endoscopic BTX injection into the sphincter of Oddi to prevent bile leakage following hepatic resection.

METHODS AND ANALYSIS

The PREBOT-II trial is an investigator-initiated, exploratory, multicentre, randomised, controlled, open-label, phase II clinical trial with two parallel study groups. 70 patients scheduled for hepatic resection will be randomised to either the intervention or the control group. Patients of the intervention group will undergo preoperative endoscopic injection of BTX into the sphincter of Oddi 3-10 days before surgery, whereas in the control group only hepatic resection will be performed. The primary endpoint is the occurrence of a postoperative bile leakage within 30 days after hepatic resection according to the definition of the International Study Group of Liver Surgery. The secondary endpoints comprise further postoperative morbidity parameters such as severity of postoperative bile leakage, post-hepatectomy haemorrhage or liver failure, mortality and quality of life up to 3 months after hepatic resection. Safety and feasibility of the procedure will also be recorded.

ETHICS, FUNDING AND DISSEMINATION

The PREBOT-II trial has been approved by the German Federal Institute for Drugs and Medical Devices (reference number 4044932) and the Ethics Committee of Heidelberg University (reference number AFmu-558/2021). This trial is supported by the German Federal Ministry of Education and Research. The results will be presented at national and international conferences and published in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

DRKS00024061, EudraCT: 2020-006001-35.

Botulinum Injection Into the Proximal Intestinal Wall of Diet-Induced Obese Mice Leads to Weight Loss and Improves Glucose and Fat Tolerance

Botulinum neurotoxin (available commercially as BOTOX) has been used successfully for treatment of several neuromuscular disorders, including blepharospasm, dystonia, spasticity, and cerebral palsy in children. Our data demonstrate that injection of Botox into the proximal intestinal wall of diet-induced obese (DIO) mice induces weight loss and reduces food intake. This was associated with amelioration of hyperglycemia, hyperlipidemia, and significant improvement of glucose tolerance without alteration of energy expenditure. We also observed accelerated gastrointestinal transit and significant reductions in glucose and lipid absorption, which may account, at least in part, for the observed weight loss and robust metabolic benefits, although possible systemic effects occurring as a consequence of central and/or peripheral signaling cannot be ignored. The observed metabolic benefits were found to be largely independent of weight loss, as demonstrated by pair-feeding experiments. Effects lasted ∼8 weeks, for as long as the half-life of Botox as reported in prior rodent studies. These results have valuable clinical implications. If the observed effects are translatable in humans, this approach could lay the foundation for therapeutic approaches geared toward robust and sustained weight loss, mimicking some of the benefits of bariatric operations without its cost and complications.

Exploring the role of botulinum toxin in critical care

INTRODUCTION

Botulinum neurotoxin (BoNT) is one of the most potent and extensively studied neurotoxins with clinical applications across several different medical specialties. This review article explores the latest evidence for therapeutic applications of BoNT in patients receiving critical management in an intensive care unit (ICU).

AREAS COVERED

The authors did a literature search in PubMed, Google Scholar, and Texas Medical Center Library database for studies describing the use of BoNT in a critical care setting. They extracted information on study design, patient selection, methodology, and results of relevant studies. Based on initial identification of 85 studies and after conducting screening, the authors identified 61 studies to be included in this review. In an ICU setting, BoNT has been used for several neurological and non-neurological indications. However, the supporting evidence is mostly limited to small observational studies.

EXPERT OPINION

The use of BoNT in this setting is largely underutilized due to paucity of well-designed clinical trials and financial barriers. Further research is needed to provide evidence for the safety and efficacy of BoNT and to optimize the dosing and injection techniques for various conditions encountered in this setting.

Protocol of a randomised controlled phase II clinical trial investigating PREoperative endoscopic injection of BOTulinum toxin into the sphincter of Oddi to reduce postoperative pancreatic fistula after distal pancreatectomy: the PREBOTPilot trial

INTRODUCTION

Postoperative pancreatic fistula (POPF) is still the most frequently occurring and clinically relevant complication after distal pancreatectomy (DP). Preoperative endoscopic injection of botulinum toxin (BTX) into the sphincter of Oddi represents an innovative approach to prevent POPF. The aim of this project (PREBOTPilot) is to generate the first randomised controlled trial data on the safety, feasibility and efficacy of preoperative endoscopic BTX injection into the sphincter of Oddi to prevent clinically relevant POPF following DP.

METHODS AND ANALYSIS

PREBOTPilot is an investigator-initiated, single-centre, randomised, controlled, open-label, phase II clinical trial with two parallel study groups and an exploratory study design. 60 patients scheduled for DP will be randomised to intervention and control group. In the intervention group, patients will undergo preoperative endoscopic injection of BTX into the sphincter of Oddi, whereas in the control group no preoperative endoscopy will be performed. The combined primary endpoint is the occurrence of clinically relevant POPF and/or death within 30 days after DP. The secondary endpoints comprise further postoperative outcome parameters and quality of life up to 3 months after DP as well as safety and feasibility of the procedure. Statistical analysis is based on the modified intention-to-treat population, excluding patients without status post DP. For safety analysis, rates of adverse events (AEs) and serious AEs will be calculated with 95% CIs for group comparisons.

ETHICS, FUNDING AND DISSEMINATION

PREBOTPilot has been approved by the German Federal Institute for Drugs and Medical Devices (reference number 4043654) and the Ethics Committee of Heidelberg University (reference number AFmo-523/2019). This trial is supported by the German Federal Ministry of Education and Research (BMBF). The results of the trial will be presented at national and international conferences and published in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

DRKS00020401.

Management of the pancreatic transection plane after left (distal) pancreatectomy: Expert consensus guidelines by the International Study Group of Pancreatic Surgery (ISGPS)

BACKGROUND

The aim was to evaluate the various operative techniques and outcomes used to manage the pancreatic transection plane (or stump) during a left (distal) pancreatectomy and to develop expert consensus guidelines.

METHODS

Evidence-based, clinically relevant questions were discussed and then were circulated among members of the International Study Group of Pancreatic Surgery. After agreement on the questions and statements, voting in a 9-point Likert scale was used to gauge the level of objective support for each.

RESULTS

Studies using the International Study Group of Pancreatic Surgery definition of postoperative pancreatic fistula including 16 randomized trials were reviewed to generate a series of statements set into 14 domains. There was strong consensus in the following statements: there was no difference in the postoperative pancreatic fistula rate after left pancreatectomy between the handsewn and stapler techniques; a stapling technique could not be used in all cases of left pancreatectomy; the use of an energy-based tissue sealant or a chemical sealant device or combinations of these did not impact the postoperative pancreatic fistula rate; there was no difference in the postoperative pancreatic fistula rate between the open, laparoscopic, or robotic approaches; and there are 1 or more clinically important, patient-related risk factors associated with the postoperative pancreatic fistula rate. There was weak or conditional agreement on the use of prophylactic somatostatin analogs, stents, stump closure, stump anastomosis, and the role of abdominal drains.

CONCLUSION

Areas of strong consensus suggests a change in clinical practice and priority setting. Eight domains with lower agreement will require novel approaches and large multicenter studies to determine future key areas of practice.

Gastrointestinal Uses of Botulinum Toxin

Botulinum toxin (BT), one of the most powerful inhibitors that prevents the release of acetylcholine from nerve endings, represents an alternative therapeutic approach for "spastic" disorders of the gastrointestinal tract such as achalasia, gastroparesis, sphincter of Oddi dysfunction, chronic anal fissures, and pelvic floor dyssynergia.BT has proven to be safe and this allows it to be a valid alternative in patients at high risk of invasive procedures but long-term efficacy in many disorders has not been observed, primarily due to its relatively short duration of action. Administration of BT has a low rate of adverse reactions and complications. However, not all patients respond to BT therapy, and large randomized controlled trials are lacking for many conditions commonly treated with BT.The local injection of BT in some conditions becomes a useful tool to decide to switch to more invasive therapies. Since 1980, the toxin has rapidly transformed from lethal poison to a safe therapeutic agent, with a significant impact on the quality of life.

The Role of Endotherapy in Recurrent Acute Pancreatitis

Patients with recurrent acute pancreatitis (RAP) have few treatment options available to them to manage their symptoms or prevent progression to chronic pancreatitis. At present, endotherapy is typically pursued as a means to achieve symptom remission and reduce rates of recurrence, hospitalization, abdominal pain, narcotic use, and surgical intervention. However, evidence that endotherapy effectively alters the natural history of disease remains limited. This article reviews the recent literature on the efficacy of endoscopic intervention in the treatment RAP with a focus on high-quality prospective randomized controlled studies. Additional studies are needed to corroborate these findings.

Reproducibility of preoperative endoscopic injection of botulinum toxin into the sphincter of Oddi to prevent postoperative pancreatic fistula

Background

A postoperative pancreatic fistula (POPF) is the most common and potentially life-threatening surgical complication in pancreatic surgery. One possible pharmacological treatment could be the endoscopic injection of botulinum toxin (BTX) into the sphincter of Oddi to prevent POPF. Promising data reported a significantly reduced rate of clinically relevant POPF. We analyzed the effect of BTX injection in our patients undergoing distal pancreatectomy (DP).

Methods

A retrospective analysis of patients undergoing DP was performed. Patients with preoperative endoscopic injection of BTX into the sphincter of Oddi were included. The end points were postoperative outcomes including POPF. BTX patients were compared with a historical cohort and matched in a 1:1 ratio using a propensity score analysis.

Results

A total of 19 patients were treated with endoscopic injection of BTX before open (n=8) or laparoscopic (n=11) DP. The median age of the patients was 67 years and the mean body mass index was 25.9 kg/m². In median, the intervention was performed 1 day (range, 0–14 days) before the operation. There were no intervention-related complications. The incidence of POPF was not statistically different between the two groups: a clinically relevant POPF grade (B/C) occurred in 32% (BTX) and 42% (control; p=0.737). Likewise, there were no significant differences in postoperative drain fluid amylase levels, morbidity, and mortality.

Conclusion

The present study could not reproduce the published results of a significant lowering of grade B/C POPF. The explanations could be the timing of BTX injection before surgery and the endoscopic technique of BTX injection. However, the conflicting results after BTX injection in two high-volume centers prompt a randomized controlled multicenter trial with trained endoscopists.

[Sphincter of Oddi dyskinesia]

Sphincter of Oddi dyskinesia is a functional disorder of the papillary region which can lead to clinical symptoms due to functional obstruction of biliary and pancreatic outflow. Based on the severity of the clinical symptoms the disorder can be graded into three types (biliary and pancreatic types I-III). The manometric diagnosis of this disorder using sphincter of Oddi manometry is hampered by the relatively high risk of pancreatitis after endoscopic retrograde cholangiopancreatography. Although papillary manometry is often carried out in North America, in Europe this is the exception rather than the rule. Manometrically, sphincter of Oddi dyskinesia is characterized by an increased pressure in the biliary and/or the pancreatic sphincter segments and can be treated by endoscopic papillotomy. This overview counterbalances the arguments for primary invasive diagnostics and a pragmatic clinical approach, i.e. papillotomy should be directly carried out when a sphincter of Oddi dyskinesia is clinically suspected. For patients with biliary or pancreatic type I, endoscopic papillotomy is the treatment of choice. In biliary type II sphincter of Oddi manometry could be helpful for clinical decision-making; however, the exact risk-benefit ratio is still difficult to assess. In type III patient selection and the low predictive value of manometry for treatment success questions the clinical usefulness of sphincter of Oddi manometry.

Rome IV. Gallbladder and Sphincter of Oddi Disorders

The concept that motor disorders of the gallbladder, cystic duct and sphincter of Oddi can cause painful syndromes is attractive and popular, at least in the USA. However, the results of commonly performed ablative treatments (cholecystectomy and sphincterotomy) are not uniformly good. The predictive value of tests that are often used to diagnose dysfunction (dynamic gallbladder scintigraphy and sphincter manometry) is controversial. Evaluation and management of these patients is made difficult by the fluctuating symptoms and the placebo effect of invasive interventions. A recent stringent study has shown that sphincterotomy is no better than sham treatment in patients with post-cholecystectomy pain and little or no objective abnormalities on investigation, so that the old concept of sphincter of Oddi dysfunction (SOD) type III is discarded. ERCP approaches are no longer appropriate in that context. There is a pressing need for similar prospective studies to provide better guidance for clinicians dealing with these patients. We need to clarify the indications for cholecystectomy in patients with Functional Gallbladder Disorder (FGBD) and the relevance of sphincter dysfunction in patients with some evidence for biliary obstruction (previously SOD type II, now called "Functional Biliary Sphincter Disorder - FBSD") and with idiopathic acute recurrent pancreatitis.

Treatment of gastrointestinal sphincters spasms with botulinum toxin A

Botulinum toxin A inhibits neuromuscular transmission. It has become a drug with many indications. The range of clinical applications has grown to encompass several neurological and non-neurological conditions. One of the most recent achievements in the field is the observation that botulinum toxin A provides benefit in diseases of the gastrointestinal tract. Although toxin blocks cholinergic nerve endings in the autonomic nervous system, it has also been shown that it does not block non-adrenergic non-cholinergic responses mediated by nitric oxide. This has promoted further interest in using botulinum toxin A as a treatment for overactive smooth muscles and sphincters. The introduction of this therapy has made the treatment of several clinical conditions easier, in the outpatient setting, at a lower cost and without permanent complications. This review presents current data on the use of botulinum toxin A in the treatment of pathological conditions of the gastrointestinal tract.

Acute recurrent pancreatitis: Etiopathogenesis, diagnosis and treatment

Acute recurrent pancreatitis (ARP) refers to a clinical entity characterized by episodes of acute pancreatitis which occurs on more than one occasion. Recurrence of pancreatitis generally occurs in a setting of normal morpho-functional gland, however, an established chronic disease may be found either on the occasion of the first episode of pancreatitis or during the follow-up. The aetiology of ARP can be identified in the majority of patients. Most common causes include common bile duct stones or sludge and bile crystals; sphincter of oddi dysfunction; anatomical ductal variants interfering with pancreatic juice outflow; obstruction of the main pancreatic duct or pancreatico-biliary junction; genetic mutations; alcohol consumption. However, despite diagnostic technologies, the aetiology of ARP still remains unknown in up to 30% of cases: in these cases the term “idiopathic” is used. Because occult bile stone disease and sphincter of oddi dysfunction account for the majority of cases, cholecystectomy, and eventually the endoscopic biliary and/or pancreatic sphincterotomy are curative in most of cases. Endoscopic biliary sphincterotomy appeared to be a curative procedure per se in about 80% of patients. Ursodeoxycholic acid oral treatment alone has also been reported effective for treatment of biliary sludge. In uncertain cases toxin botulin injection may help in identifying some sphincter of oddi dysfunction, but this treatment is not widely used. In the last twenty years, pancreatic endotherapy has been proven effective in cases of recurrent pancreatitis depending on pancreatic ductal obstruction, independently from the cause of obstruction, and has been widely used instead of more aggressive approaches.

Endoscopic therapy for acute recurrent pancreatitis

Endoscopy plays an important role in both the diagnosis and the initial management of recurrent acute pancreatitis, as well as the investigation of refractory disease, but it has known limitations and risks. Sound selective use of these therapies, complemented with other lines of investigation such as genetic testing, can dramatically improve frequency of attacks and associated quality of life. Whether endoscopic therapy can reduce progression to chronic pancreatitis, or reduce the risk of malignancy, is debatable, and remains to be proven.

Endoscopic approach to the patient with motility disorders of the bile duct and sphincter of Oddi

Since its original description by Oddi in 1887, the sphincter of Oddi has been the subject of much study. Furthermore, the clinical syndrome of sphincter of Oddi dysfunction (SOD) and its therapy are controversial areas. Nevertheless, SOD is commonly diagnosed and treated by physicians. This article reviews the epidemiology, clinical manifestations, and current diagnostic and therapeutic modalities of SOD.

The Size of the Papilla of Vater and Its Relation to Its Height in Comparison with the Visibility of the Sphincter of Oddi before and after Cholecystectomy

This study investigated the changes in the surface area and height of the papilla of Vater (PV) and the visibility of the sphincter of Oddi complex (SOK) using endoscopic ultrasound (EUS) examinations of 80 patients with symptomatic gallstones before and at 3 and 6 months after cholecystectomy. Following surgery, 50 patients experienced early atypical symptoms characteristic of postcholecystectomy syndrome (PCS) and 30 patients were asymptomatic. The PV measurements were greater in all patients compared with normal reference values and increased significantly from before surgery to 3 months postsurgery. At 6 months postsurgery, both the surface area and height of the PV had significantly decreased to preoperative values but remained higher than normal. The proportion of patients with a visible SOK had increased by 3 months postsurgery but had reduced again by 6 months. There were no significant differences between symptomatic and asymptomatic patients, suggesting that the changes observed in the PV and SOK do not explain the presence of the atypical symptoms of PCS.

Endoscopic papillary balloon dilation for removal of choledocholithiasis: indications, advantages, complications, and long-term follow-up results

Endoscopic papillary balloon dilation (EPBD) is an alternative method of endoscopic sphincterotomy (EST). Although concerns regarding post-procedure pancreatitis have been expressed, EPBD has come to be recognized as an effective and safe method for stone removal in specific cases. To analyze the proper indications, ideal methods, complications, and long-term follow-up results for EPBD, we reviewed articles about EPBD located through a search of the PubMed data base. We analyzed the ballooning methods, indications, results and complications of EPBD among the articles found and compared the results with those of EST. We considered the authors' own clinical experience and knowledge in developing recommendations for EPBD. EPBD showed similar efficacy and safety for the removal of choledocholithiasis to that of EST. Although large or multiple stones were difficult to remove by EPBD, it was safer and easier to apply in patients with coagulopathy or abnormal anatomy. To prevent severe pancreatitis, excessive ballooning and impractical cannulation should be avoided, and precut sphincterotomy or adjuvant prophylaxis should be considered. Due to its preservation of the sphincter of Oddi, EPBD is expected to have fewer long-term complications, such as stone recurrence, cholangitis and cholecystitis. In conclusion, EPBD appears to be safe and effective for the treatment of choledocholithiasis with proper selection of ballooning methods and patients.

Endoscopy in the diagnosis and management of motility disorders

BACKGROUND

Gastrointestinal illness may result from either an underlying structural abnormality (e.g. neoplastic obstruction), or a functional disorder (e.g. motor diarrhea), or both (e.g. achalasia with squamous esophageal cancer).

AIMS

The purpose of this study was to highlight the potential value and role of endoscopy in the recognition and management of patients with functional and motility disorders.

METHODS

We performed a literature review in PubMed.

RESULTS

Diagnostic and therapeutic endoscopy may be under-used by motility-oriented gastroenterologists; in contrast, motility and other functional studies may be under-used by endoscopists. Yet, many areas of cross-exchange exist.

CONCLUSIONS

This review aims to guide the appropriate indications for the use of endoscopy in diagnosing and treating functional GI and motility disorders and serve as a bridge and a forum of exchange between endoscopists and motility specialists.

Biliary dyskinesia

Functional disorders of the biliary tract include gallbladder dyskinesia (GBD) and sphincter of Oddi dysfunction (SOD). The diagnosis of GBD is made if the gallbladder ejection fraction is less than 35% to 40% using cholecystokinin cholescintigraphy. Despite slightly inferior outcomes compared with calculous disease, patients who have GBD should be treated with cholecystectomy. SOD is most often noted in the postcholecystectomy patient and symptoms can be biliary or pancreatic in nature. The gold standard for diagnosis remains manometry, with basal biliary or pancreatic sphincter pressures measuring greater than 40 mm Hg. Patients who have increased pressures may benefit from endoscopic sphincterotomy.

Sphincter of Oddi dysfunction and bile duct microlithiasis in acute idiopathic pancreatitis

Although there are numerous causes of acute pancreatitis, an etiology cannot always be found. Two potential etiologies, microlithiasis and sphincter of Oddi dysfunction, are discussed in this review. Gallbladder microlithiasis, missed on transcutaneous ultrasound, is reported as the cause of idiopathic acute pancreatitis in a wide frequency range of 6%-80%. The best diagnostic technique for gallbladder microlithiasis is endoscopic ultrasound although biliary crystal analysis and empiric cholecystectomy remain as reasonable options. In contrast, in patients who are post-cholecystectomy, bile duct microlithiasis does not appear to have a role in the pathogenesis of acute pancreatitis. Sphincter of Oddi dysfunction is present in 30%-65% of patients with idiopathic acute recurrent pancreatitis in whom other diagnoses have been excluded. It is unclear if this sphincter dysfunction was the original etiology of the first episode of pancreatitis although it appears to have a causative role in recurring episodes since sphincter ablation decreases the frequency of recurrent attacks. Unfortunately, this conclusion is primarily based on small retrospective case series; larger prospective studies of the outcome of pancreatic sphincterotomy for SOD-associated acute pancreatitis are sorely needed. Another problem with this diagnosis and its treatment is the concern over potential procedure related complications from endoscopic retrograde cholangiopancreatography (ERCP), manometry and pancreatic sphincterotomy. For these reasons, patients should have recurrent acute pancreatitis, not a single episode, and have a careful informed consent before assessment of the sphincter of Oddi is undertaken.

Endoscopic therapy in acute recurrent pancreatitis

Endoscopic retrograde cholangiopancreatography (ERCP) has evolved from a largely diagnostic to a largely therapeutic modality. Cross-sectional imaging, such as computed tomography (CT) and magnetic resonance imaging (MRI), and less invasive endoscopy, especially endoscopic ultrasound (EUS), have largely taken over from ERCP for diagnosis. However, ERCP remains the “first line” therapeutic tool in the management of mechanical causes of acute recurrent pancreatitis, including bile duct stones (choledocholithiasis), ampullary masses (benign and malignant), congenital variants of biliary and pancreatic anatomy (e.g. pancreas divisum, choledochoceles), sphincter of Oddi dysfunction (SOD), pancreatic stones and strictures, and parasitic disorders involving the biliary tree and/or pancreatic duct (e.g Ascariasis, Clonorchiasis).

Status quo of endoscopic management in chronic pancreatitis

The incidence of chronic pancreatitis (CP) is increasing all over the world. However, it is rather difficult to treat it because its etiological factor and pathogenesis are still unclear. In recent years, the rapid advances in endoscopy techniques have provided new treatment modalities for CP. We, in this paper, describe the present status and advances in endoscopy for CP as well as the problems and difficulties, thus contributing to the treatment for CP.

Botulinum toxin: Clinical use

Since its development for the use of blepharospasm and strabismus more than 2.5 decades ago, botulinum neurotoxin (BoNT) has become a versatile drug in various fields of medicine. It is the standard of care in different disorders such as cervical dystonia, hemifacial spasm, focal spasticity, hyperhidrosis, ophthalmological and otolaryngeal disorders. It has also found widespread use in cosmetic applications. Many other indications are currently under investigation, including gastroenterologic and urologic indications, analgesic management and migraine. This paper is an extensive review of the spectrum of BoNT clinical applications.

Botulinum toxin for gastrointestinal disorders: therapy and mechanisms

Botulinum toxin has gained widespread acceptance as a treatment option for various spastic gastrointestinal disorders such as achalasia, gastroparesis, sphincter of Oddi dysfunction, chronic anal fissures, and pelvic floor dyssnergia, despite the lack of strong evidence supporting its use in many of these diseases. This review summarizes the trials investigating the use of BoNT since it was first utilized as a treatment in achalasia. BoNT has proven to be safe, but long-term efficacy in many disorders has not been observed, primarily due to is relatively short duration of action. BoNT may be most useful in confirming a diagnosis which can lead to a more definitive treatment modality. Furthermore, its safety profile allows it to be a useful alternative in patients who are at high risk for invasive procedures.

Systematic review: sphincter of Oddi dysfunction--non-invasive diagnostic methods and long-term outcome after endoscopic sphincterotomy

BACKGROUND

Sphincter of Oddi dysfunction is a benign, functional gastrointestinal disorder for which invasive endoscopic therapy with potential complications is often recommended.

AIMS

To review the available evidence regarding the diagnostic accuracy of non-invasive methods that have been used to establish the diagnosis and to estimate the long-term outcome after endoscopic sphincterotomy.

METHODS

A systematic review of English language articles and abstracts containing relevant terms was performed.

RESULTS

Non-invasive diagnostic methods are limited by their low sensitivity and specificity, especially in patients with Type III sphincter of Oddi dysfunction. Secretin-stimulated magnetic resonance cholangiopancreatography appears to be useful in excluding other potential causes of symptoms, and morphine-provocated hepatobiliary scintigraphy also warrants further study. Approximately 85%, 69% and 37%, of patients with biliary Types I, II and III sphincter of Oddi dysfunction, respectively, experience sustained benefit after endoscopic sphincterotomy. In pancreatic sphincter of Oddi dysfunction, approximately 75% of patients report symptomatic improvement after pancreatic sphincterotomy, but the studies have been non-controlled and heterogeneous.

CONCLUSIONS

Patients with suspected sphincter of Oddi dysfunction, particularly those with biliary Type III, should be carefully evaluated before considering sphincter of Oddi manometry and endoscopic sphincterotomy. Further controlled trials are needed to justify the invasive management of patients with biliary Type III and pancreatic sphincter of Oddi dysfunction.

Sphincter of Oddi dysfunction: managing the patient with chronic biliary pain

Sphincter of Oddi dysfunction (SOD) is a syndrome of chronic biliary pain or recurrent pancreatitis due to functional obstruction of pancreaticobiliary flow at the level of the sphincter of Oddi. The Milwaukee classification stratifies patients according to their clinical picture based on elevated liver enzymes, dilated common bile duct and presence of abdominal pain. Type I patients have pain as well as abnormal liver enzymes and a dilated common bile duct. Type II SOD consists of pain and only one objective finding, and Type III consists of biliary pain only. This classification is useful to guide diagnosis and management of sphincter of Oddi dysfunction. The current gold standard for diagnosis is manometry to detect elevated sphincter pressure, which correlates with outcome to sphincterotomy. However, manometry is not widely available and is an invasive procedure with a risk of pancreatitis. Non-invasive testing methods, including fatty meal ultrasonography and scintigraphy, have shown limited correlation with manometric findings but may be useful in predicting outcome to sphincterotomy. Endoscopic injection of botulinum toxin appears to predict subsequent outcome to sphincterotomy, and could be useful in selection of patients for therapy, especially in the setting where manometry is unavailable.

Other indications of botulinum toxin therapy

The therapeutic possibilities of botulinum toxin are manifold and certainly not yet fully exhausted. Apart from the classical indications--focal dystonia and focal spasticity--its use in the management of wrinkles has become well known. Moreover, the toxin is now being administered in many medical fields, including many other kinetic disorders like rare dystonias and tremor. The toxin is also used in a great number of autonomic disorders such as focal hyperhidrosis and even rhinitis. Substantial advances have been made in the field of urology after injections into the sphincter and detrusor muscle. Studies for approval are meanwhile under way concerning the treatment of detrusor hyperreflexia. Gastroenterology is another important field for application of botulinum toxin--be it to the esophagus (e.g. achalasia), stomach, gallbladder, or anorectum. Anal fissure is considered a particularly common indication. Controlled studies for many indications are frequently lacking because of the limited incidence of some of these disorders and symptoms.

Sphincter of oddi dysfunction

Sphincter of Oddi dysfunction (SOD) is a benign noncalculous obstruction of bile or pancreatic drainage at the level of the sphincter of Oddi. The disorder is clinically associated with either biliary pain or idiopathic pancreatitis, depending on the portion of the sphincter affected. Patients with suspected SOD are subdivided into three categories: these are type I, II, and III, depending on associated clinical evidence for the diagnosis. Multiple noninvasive tests have been utilized to aid in the diagnosis but have been complicated by poor sensitivity and specificity. Sphincter of Oddi manometry is the gold standard for confirming the diagnosis, although questions remain about its sensitivity and specificity. Sphincterotomy of the affected portion of the sphincter is the treatment of choice and has been shown effective for palliation of symptoms in two sham-controlled studies of patients with suspected type II biliary SOD.

Endoscopic balloon dilation compared with sphincterotomy for extraction of bile duct stones

BACKGROUND AND AIMS

Endoscopic retrograde cholangiopancreatography is commonly performed to remove bile duct stones. The aim of this study was to determine short-term outcomes of endoscopic balloon dilation of the sphincter of Oddi compared with sphincterotomy for stone extraction.

METHODS

A randomized, controlled multicenter study of 117 patients assigned to dilation and 120 to sphincterotomy was performed in a spectrum of clinical and academic practices.

RESULTS

Characteristics of the patients, procedures, and endoscopists were similar except that dilation patients were younger. Procedures were successful in 97.4% and 92.5% of the dilation and sphincterotomy patients, respectively. Overall morbidity occurred in 17.9% and 3.3% ( P < .001; difference, 14.6; 95% confidence interval, 7-22.3) and severe morbidity, including 2 deaths, in 6.8% and 0%( P < .004; difference, 6.8; 95% confidence interval, 2.3-11.4) for dilation and sphincterotomy, respectively. Complications for dilation and sphincterotomy, respectively, included: pancreatitis, 15.4% and .8% ( P < .001; difference, 14.6; 95% confidence interval, 7.8-21.3); cystic duct fistula, 1.7% and 0%; cholangitis, .9% and .8%; perforation, 0% and .8%; and cholecystitis, 0% and .8%. There were 2 deaths (1.7%) due to pancreatitis following dilation and none with sphincterotomy. The study was terminated at the first interim analysis. Dilation patients required significantly more invasive procedures, longer hospital stays, and longer time off from normal activities.

CONCLUSIONS

In a broad spectrum of patients and practices, endoscopic balloon dilation compared with sphincterotomy for biliary stone extraction is associated with increased short-term morbidity rates and death due to pancreatitis. Balloon dilation of the sphincter of Oddi for stone extraction should be avoided in routine practice.

Noncosmetic uses of botulinum toxin

In conclusion, botulinum toxin usage over the past 2 to 3 decades has expanded exponentially. Almost every discipline in medicine has found some therapeutic use for this toxin. Botulinum toxin has been shown to be safe, effective, and relatively easy to administer with proper training.

Treatment with botulinum neurotoxin of gastrointestinal smooth muscles and sphincters spasms

Local injections of botulinum neurotoxin are now considered an efficacious treatment for neurological and non-neurological conditions. One of the most recent achievements in the field is the observation that botulinum neurotoxin provides benefit in diseases of the gastrointestinal tract. Botulinum neurotoxin inhibits contraction of gastrointestinal smooth muscles and sphincters; it has also been shown that the neurotoxin blocks cholinergic nerve endings in the autonomic nervous system, but it does not block nonadrenergic responses mediated by nitric oxide. This aspect has further promoted the interest to use botulinum neurotoxin as a treatment for overactive smooth muscles, such as the anal sphincters to treat anal fissure and outlet-type constipation, or the lower esophageal sphincter to treat esophageal achalasia. Knowledge of the anatomical and functional organization of innervation of the gastrointestinal tract is a prerequisite to understanding many features of botulinum neurotoxin action on the gut and the effects of injections placed into specific sphincters. This review presents current data on the use of botulinum neurotoxin to treat diseases of the gastrointestinal tract and summarizes recent knowledge on the pathogenesis of disorders of the gut due to a dysfunction of the enteric nervous system.

Noncosmetic uses of botulinum toxin

Since the introduction of botulinum toxin (BTX) as a therapeutic tool in the 1970s, the number of uses for this substance has increased exponentially. BTX's mechanism of action involves degrading the SNARE proteins blockading the release of acetylcholine into the neuromuscular junction. In many body systems, decrease of contractility, strength, and tension of certain muscle groups result in improved clinical outcomes. Applications now include cosmetic, gastroenterologic, otolaryngologic, genitourinary, neurologic, and dermatologic uses. In fact, BTX can be considered as a potential treatment in any situation involving inappropriate or exaggerated muscle contraction. Currently, the FDA has approved BTX-A (Botox) for treating glabellar lines, blepharospasm, strabismus, hemifacial spasm, cervical dystonia, and spasticity. With the addition of cosmetic applications to the FDA's approval list, the use of BTX has increased dramatically.

Therapeutic endoscopic retrograde cholangiopancreatography: what the future holds

These are exciting times for interventional endoscopists performing ERCP. The advent of noninvasive, diagnostic techniques of the pancreaticobiliary tree has resulted in a shift toward more therapeutic procedures. The combination of major technologic advances together with endoscopists' growing comfort with invasive procedures has helped to push the boundaries of endoscopic therapy. These therapies, however, should always be sanctioned by sound science and well-controlled clinical trials.

Sphincter of Oddi dysfunction and other functional biliary disorders: evaluation and treatment

Functional biliary disorders encompass the conditions of SOD and gallbladder dysmotility, both of which result in clinical pain syndromes. Obtaining objective diagnostic and outcomes data for both disorders has been an ongoing challenge over the last two decades. SOD, although initially believed to be strictly a biliary disorder, has now been implicated in recurrent pancreatitis. The biliary-type classification allows a clinician to stratify patients who would benefit from SOM and endoscopic sphincterotomy. Further study into the impact of endoscopic therapy for recurrent pancreatitis is needed. By the same token, the dilemma of postcholecystectomy abdominal pain, whether classified as biliary or pancreatic type III, remains challenging. The current limitations of knowledge highlight the need for prospective randomized studies to evaluate the clinical significance of SOM abnormalities to facilitate treatment of these patients.