Correlation of basal sphincter pressures measured from the bile duct and the pancreatic duct in patients with suspected sphincter of Oddi dysfunction

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.

Sphincter of Oddi dysfunction and pancreatitis

Sphincter of Oddi dysfunction (SOD) is a term used to describe a group of heterogenous pain syndromes caused by abnormalities in sphincter contractility. Biliary and pancreatic SOD are each sub-classified as type I, II or III, according to the Milwaukee classification. SOD appears to carry an increased risk of acute pancreatitis as well as rates of post ERCP pancreatitis of over 30%. Various mechanisms have been postulated but the exact role of SOD in the pathophysiology of acute pancreatitis is unknown. There is also an association between SOD and chronic pancreatitis but it is still unclear if this is a cause or effect relationship. Management of SOD is aimed at sphincter ablation, usually by endoscopic sphincterotomy (ES). Patients with type I SOD will benefit from ES in 55%-95% of cases. Sphincter of Oddi manometry is not necessary before ES in type I SOD. For patients with types II and III the benefit of ES is lower. These patients should be more thoroughly evaluated before performing ES. Some researchers have found that manometry and ablation of both the biliary and pancreatic sphincters is required to adequately assess and treat SOD. In pancreatic SOD up to 88% of patients will benefit from sphincterotomy. Therefore, there have been calls from some quarters for the current classification system to be scrapped in favour of an overall system encompassing both biliary and pancreatic types. Future work should be aimed at understanding the mechanisms underlying the relationship between SOD and pancreatitis and identifying patient factors that will help predict benefit from endoscopic therapy.

Role of endoscopic retrograde cholangiopancreatography in acute pancreatitis

Endoscopic retrograde cholangiopancreatography (ERCP) is a useful tool in the evaluation and management of acute pancreatitis. This review will focus on the role of ERCP in specific causes of acute pancreatitis, including microlithiasis and gallstone disease, pancreas divisum, Sphincter of Oddi dysfunction, tumors of the pancreaticobiliary tract, pancreatic pseudocysts, and pancreatic duct injury. Indications for endoscopic techniques such as biliary and pancreatic sphincterotomy, stenting, stricture dilation, treatment of duct leaks, drainage of fluid collections and stone extraction will also be discussed in this review. With the advent of less invasive and safer diagnostic modalities including endoscopic ultrasound (EUS) and magnetic retrograde cholangiopancreatography (MRCP), ERCP is appropriately becoming a therapeutic rather than diagnostic tool in the management of acute pancreatitis and its complications.

Sphincter of Oddi dysfunction and pancreatitis

Sphincter of Oddi dysfunction (SOD) is a term used to describe a group of heterogenous pain syndromes caused by abnormalities in sphincter contractility. Biliary and pancreatic SOD are each sub-classified as typeI, II or III, according to the Milwaukee classification. SOD appears to carry an increased risk of acute pancreatitis as well as rates of post ERCP pancreatitis of over 30%. Various mechanisms have been postulated but the exact role of SOD in the pathophysiology of acute pancreatitis is unknown. There is also an association between SOD and chronic pancreatitis but it is still unclear if this is a cause or effect relationship. Management of SOD is aimed at sphincter ablation, usually by endoscopic sphincterotomy (ES). Patients with typeISOD will benefit from ES in 55%-95% of cases. Sphincter of Oddi manometry is not necessary before ES in typeISOD. For patients with types II and III the benefit of ES is lower. These patients should be more thoroughly evaluated before performing ES. Some researchers have found that manometry and ablation of both the biliary and pancreatic sphincters is required to adequately assess and treat SOD. In pancreatic SOD up to 88% of patients will benefit from sphincterotomy. Therefore, there have been calls from some quarters for the current classification system to be scrapped in favour of an overall system encompassing both biliary and pancreatic types. Future work should be aimed at understanding the mechanisms underlying the relationship between SOD and pancreatitis and identifying patient factors that will help predict benefit from endoscopic therapy.

Role of endoscopic retrograde cholangiopancreatography in acute pancreatitis

Endoscopic retrograde cholangiopancreatography (ERCP) is a useful tool in the evaluation and management of acute pancreatitis. This review will focus on the role of ERCP in specific causes of acute pancreatitis, including microlithiasis and gallstone disease, pancreas divisum, Sphincter of Oddi dysfunction, tumors of the pancreaticobiliary tract, pancreatic pseudocysts, and pancreatic duct injury. Indications for endoscopic techniques such as biliary and pancreatic sphincterotomy, stenting, stricture dilation, treatment of duct leaks, drainage of fluid collections and stone extraction will also be discussed in this review. With the advent of less invasive and safer diagnostic modalities including endoscopic ultrasound (EUS) and magnetic retrograde cholangiopancreatography (MRCP), ERCP is appropriately becoming a therapeutic rather than diagnostic tool in the management of acute pancreatitis and its complications.

Diagnosing and treating Sphincter of Oddi dysfunction: a critical literature review and reevaluation

Sphincter of Oddi dysfunction is a pathologic syndrome, without considering etiology, physiopathology, or anatomic aspects of the condition. The clinical manifestations of the syndrome may be a consequence of an "organic stenosis" of the tract or a consequence of "abnormal motility" of the sphincter. Until some years ago, the gold standard technique for studying and treating this pathologic condition was endoscopic retrograde cholangiopancreatography. Two criteria for defining patients in the Milwaukee classification are related to this procedure. The Milwaukee classification was introduced to use clinical and radiologic criteria to define patients with Sphincter of Oddi dysfunction to choose the best treatment. Subsequently, great emphasis has been placed on manometry of the sphincter performed by endoscopic cannulation. The enormous increase of cholecystectomies by means of laparoscopic technique has increased the number of patients who return to their reference-surgeon with a post-cholecystectomy pain and possible Sphincter of Oddi dysfunction. The aim of this paper is to review the literature and to evaluate an up-to-date flow chart for diagnosing and treating the syndrome by using alternative diagnostic procedures that are less invasive than endoscopic retrograde cholangiopancreatography.

Prevalence of sphincter of Oddi dysfunction: can results from specialized centers be generalized?

Recent studies suggest a high prevalence of sphincter of Oddi dysfunction (SOD) in patients referred to specialized centers for sphincter of Oddi manometry (SOM). Whether these results can be generalized to other centers is unknown. From September 1998 to April 2000, patients undergoing SOM were prospectively identified. Patients were classified as having either biliary or pancreatic SOD, according to the modified Milwaukee classification, and underwent SOM of either the biliary or pancreatic sphincter based on clinical history. SOD was diagnosed when the mean basal sphincter pressure was >40 mm Hg. Standard cholangiography and/or pancreatography were performed following manometry. Fifty-one patients were studied (43 women, median age 46 years, range 7-74 years). Prior to SOM, patients were classified by the modified Milwaukee classification as biliary type I in 1 patient, type II in 8, and type III in 20; pancreatic type I in 4 patients, type II in 14, and type III in 3; and biliary type III and pancreatic type III in 1 patient. Indications for SOM included abdominal pain in 35 patients (69%), recurrent idiopathic pancreatitis in 12 (24%), chronic pancreatitis in 3 (7%), and acute pancreatitis in 1 (2%). Overall, 30 patients (59%; 95% CI 41.1-76.9%) were found to have SOD; abnormal biliary sphincter pressure in 16 of 29 patients (55%) undergoing biliary manometry, and abnormal pancreatic sphincter pressures in 14 of 21 patients (67%) undergoing pancreatic sphincter manometry, and abnormal biliary and pancreatic sphincter pressures in 1. SOD was diagnosed in 1 biliary type I patient (100%), 4 type II patients (50%), and 11 type III patients (52.4%) with a mean pressures of 92, 47, and 80 mm Hg, respectively. SOD was identified in 4 pancreatic type I patients (100%), 7 type II patients (50%), and 3 type III patients (100%) with mean sphincter pressures of 83 mm Hg, 96 mm Hg, and 102 mm Hg, respectively. In conclusion, the prevalence of SOD in patients with suspected biliary disease was 55%, suspected pancreatic disease 66%, yielding an overall prevalence of SOD of 59%. These results confirm the high prevalence of SOD in patients referred for SOM.

Sphincter of Oddi (pancreatic) hypertension and recurrent pancreatitis

Major papilla pancreatic sphincter dysfunction, a variant of sphincter of Oddi dysfunction, causes pancreatitis and pancreatic-type pain. The gold standard for diagnosis is sphincter of Oddi manometry, most commonly performed at endoscopic retrograde cholangiopancreatography (ERCP). Noninvasive testing, such as secretin-stimulated transabdominal or endoscopic ultrasound assessment of pancreatic duct diameter, is less reliable and has relatively low sensitivity. Two thirds of patients with biliary sphincter of Oddi dysfunction have elevated pancreatic basal sphincter pressure. To maximize the diagnostic yield of sphincter of Oddi dysfunction, both the biliary and pancreatic sphincter pressures should be measured. Patients with sphincter of Oddi dysfunction may respond to biliary sphincterotomy alone, but evaluation of their pancreatic sphincter is warranted if symptoms persist after biliary therapy alone. Whether both biliary and pancreatic sphincters should be treated at the first ERCP session is controversial. Biliary and pancreatic endoscopic sphincterotomies are associated with two- to fourfold increased incidence of pancreatitis following the procedure in patients with pancreatic sphincter hypertension. Prophylactic pancreatic duct stenting reduces the frequency and severity of complications by greater than 50%.

Idiopathic acute recurrent pancreatitis

Acute recurrent pancreatitis (ARP) results most commonly from alcohol abuse or gallstone disease. Initial evaluation fails to detect the cause of ARP in 10-30% of patients, and as a result the diagnosis of "idiopathic" ARP is given. In these patients, a more extensive evaluation including specialized labs, ERCP, endoscopic ultrasound, or magnetic resonance cholangiopancreatography typically leads to a diagnosis of microlithiasis, sphincter of Oddi dysfunction, or pancreas divisum. Less commonly, hereditary pancreatitis, cystic fibrosis, a choledochocele, annular pancreas, an anomalous pancreatobiliary junction, pancreatobiliary tumors, or chronic pancreatitis are diagnosed. Determining the etiology is important, as it helps to direct therapy, limits further unnecessary evaluation, and may improve a patient's long term prognosis.

Endoscopic retrograde cholangiopancreatography and the pancreas: when and why?

Historically, endoscopic retrograde cholangeopancreatography (ERCP) has played a unique role as a diagnostic and therapeutic modality for diseases of the pancreas. Despite the advent of new imaging techniques, ERCP continues to play a central role in the evaluation and treatment of pancreatitis of various causes. Endoscopic cholangiography and stenting remain mainstays in the palliation of inoperable obstructive jaundice in patients with cancer of the pancreas.

Hybrid classification of sphincter of Oddi dysfunction based on simplified Milwaukee criteria: effect of marginal serum liver and pancreas test elevations

To date, when using the Milwaukee classification for sphincter of Oddi dysfunction (SOD), one cannot accurately classify patients with marginal elevations in laboratory tests; ie, < 1.5 x the upper limit of normal (ULN). Since subsequent treatment may depend on how they are classified, we sought to determine whether these patients should be considered as type II or type III. Between January 1993 and October 1996, 113 consecutive patients (82 females and 31 males; ages 12-87 years) without prior sphincterotomy were referred to consider a diagnosis of SOD type II or III. SOD II patients had pancreaticobiliary-type pain and laboratory elevations >1.5 x ULN or dilated ducts, while SOD III patients had pain only. Hybrid patients had pain and marginal laboratory elevations <1.5 x ULN, with normal duct diameters. Drainage times, frequency, duration, and propagation were not assessed. Sphincter of Oddi manometry (SOM) was performed in each case, and the frequency of abnormal biliary and/or pancreatic basal sphincter pressure was compared, with respect to type II, III, and hybrid SOD. Successful SOM was obtained in 113/114 patients: Abnormal basal sphincter pressure was found in 65, 89, and 43% of type II, hybrid, and type III SOD, respectively. We found no statistical difference between type II and hybrid patients. In contrast, there was statistical difference between types II and III patients and between type III and hybrid patients. In conclusion, there was no significant difference in the frequency of elevated basal sphincter pressure in SOD type II versus hybrid, and thus they should be considered as one group.

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

AIM

To evaluate the technical feasibility, safety, and short-term efficacy of botulinum toxin injection for pancreatic sphincter of Oddi dysfunction and to analyse whether the symptomatic response to botulinum toxin might be a predictor of outcome for endoscopic sphincterotomy.

METHODS

Fifteen consecutive patients (nine female, aged 38 +/- 12 years) with frequent attacks (median four) of acute pancreatitis within 6 months, and manometrically proven pancreatic sphincter of Oddi dysfunction underwent endoscopic injection of 100 units of botulinum toxin into the major papilla. All patients underwent prospective follow-up thereafter and in cases of recurrent pancreatitis manometry this was repeated and pancreatic sphincterotomy was performed.

RESULTS

No side-effects occurred after botulinum toxin injection in any patient. Within 3 months after botulinum toxin treatment, 12 out of 15 patients remained asymptomatic (80% primary response). Only one out of three patients without symptomatic benefit showed continued elevated pancreatic sphincter pressure at manometry and only this patient benefited from pancreatic sphincterotomy later on. Eleven of the 12 patients initially responding to botulinum toxin injection developed a symptomatic relapse 6 +/- 2 months after botulinum toxin treatment. These patients then achieved long-term clinical remission from pancreatic or combined (biliary and pancreatic, n=5) sphincterotomy (median follow-up, 15 months).

CONCLUSION

Endoscopic botulinum toxin injection into the papilla of Vater is a safe procedure for treatment of pancreatic sphincter of Oddi dysfunction that may provide short-term relief in about 80% of the patients. Those patients who respond to botulinum toxin may subsequently gain definitive cure from sphincterotomy.

Sphincter of oddi manometry: is it necessary to measure both biliary and pancreatic sphincter pressures?

BACKGROUND

Data are scant on the miss rate of sphincter of Oddi dysfunction if basal pressure in both biliary and pancreatic sphincter segments is not measured during manometry.

METHODS

Motility tracings with basal pressure measurements of both sphincter segments were retrospectively analyzed. Basal sphincter pressure greater than 40 mm Hg was considered abnormal in either sphincter segment.

RESULTS

The study population consisted of 73 subjects (64 women, 9 men; age 45.3 +/- 1.6 yr). The basal pressures in the 2 sphincter segments were highly discordant (correlation coefficient = 0.2, p = 0.04). Basal pressures were normal in both segments in 19%, abnormal in both segments in 40%, and abnormal in 1 segment but normal in the other in 41%. The negative predictive value of normal biliary sphincter pressure in excluding sphincter dysfunction was 0. 42; when the pancreatic sphincter pressure was normal, the negative predictive value was 0.58. The incidence of pancreatitis with dual duct manometry was comparable to the institutional experience with all sphincter studies.

CONCLUSIONS

Although the clinical relevance of individually elevated sphincter pressures remains uncertain, there is significant discordance of basal pressures between the biliary and pancreatic sphincter segments. If only the biliary sphincter pressure were to be measured, one fourth of abnormal sphincter pressures would be missed. Therefore, if the first sphincter segment has a normal basal pressure, the other segment should also be evaluated.

Gallstones, the choledochoduodenal junction and initiation of acute pancreatitis: are two stones the culprits rather than one stone?

Reflux of biliary secretions into the pancreatic duct following gallstone obstruction of the common biliary pancreatic ampulla has been implicated as a cause of acute pancreatitis. However, the pancreatic duct pressure is higher than the biliary pressure and, therefore, the simple obstruction of the choledochoduodenal junction by one gallstone does not result in biliary pancreatic reflux. We propose a mechanism whereby simultaneous migration and sequential impaction above and below the common biliary pancreatic ampulla of two gallstones allows for the creation of a toxic bile-pancreatic juice mixture in the common bile duct, subsequent reversal of the pressure gradient and reflux of the toxic secretions into the pancreatic duct.

Frequency of abnormal pancreatic and biliary sphincter manometry compared with clinical suspicion of sphincter of Oddi dysfunction

BACKGROUND

Sphincter of Oddi manometry as performed at ERCP is the most accepted method to evaluate for sphincter of Oddi dysfunction. To fully assess for sphincter of Oddi dysfunction, both the pancreatic and the bile ducts must be evaluated. We assessed the frequency of pancreatic and biliary sphincter abnormalities in a large series of patients.

METHODS

A total of 593 patients underwent manometry of the biliary and pancreatic ducts at one endoscopic retrograde cholangiopancreatography session. Basal sphincter pressure greater than or equal to 40 mm Hg was considered abnormal. Phasic waves were not evaluated. Manometric abnormalities were correlated with the clinical presentation as categorized using a modified Geenen/Hogan classification.

RESULTS

Of 360 patients with intact sphincters, 18.9% had abnormal pancreatic sphincter basal pressure alone, 11.4% had abnormal biliary basal sphincter pressure alone, and in 31.4% the basal pressure was abnormal for both sphincters; thus, 60.1% of the patients had sphincter dysfunction. The frequency of sphincter of Oddi dysfunction did not differ whether typed by biliary or pancreatic criteria: approximately 65% type II and 59% type III. Of patients without pancreatitis, 55.9% had an abnormal basal sphincter pressure, whereas sphincter dysfunction was present in 72.3% of those with idiopathic pancreatitis and 53.9% of patients with chronic pancreatitis. Of patients with an ablated biliary sphincter, 45.9% had abnormal basal pancreatic sphincter pressure and only 0.6% had an abnormal biliary sphincter pressure alone. Abnormal pressure in both sphincters was found in 9.3%.

CONCLUSION

If both portions of the sphincter of Oddi are studied simultaneously, abnormalities are found very commonly (55% to 72%). Assessment of both sides of the sphincter is necessary. Classifying patients according to both pancreatic and biliary sphincter segments is cumbersome, and may be replaced by an overall type. Using this modified classification, the frequency of sphincter of Oddi dysfunction is similar in both type II and type III patients (59% to 67%).

Pancreatic stenting prevents pancreatitis after biliary sphincterotomy in patients with sphincter of Oddi dysfunction

BACKGROUND & AIMS

Patients with sphincter of Oddi dysfunction are at high risk of developing pancreatitis after endoscopic biliary sphincterotomy. Impaired pancreatic drainage caused by pancreatic sphincter hypertension is the likely explanation for this increased risk. A prospective, randomized controlled trial was conducted to determine if ductal drainage with pancreatic stenting protects against pancreatitis after biliary sphincterotomy in patients with pancreatic sphincter hypertension.

METHODS

Eligible patients with pancreatic sphincter hypertension were randomized to groups with pancreatic duct stents (n = 41) or no stents (n = 39) after biliary sphincterotomy. The primary measured outcome was pancreatitis after endoscopic retrograde cholangiopancreatography (ERCP).

RESULTS

Pancreatic stenting significantly decreased the risk of pancreatitis from 26% to 7% (10 of 39 in the no stent group and 3 of 41 in the stent group; P = 0.03). Only 1 patient in the stent group developed pancreatitis after sphincterotomy, and 2 others developed pancreatitis at the time of stent extraction. Patients in the no stent group were 10 times more likely to develop pancreatitis immediately after sphincterotomy than those in the stent group (relative risk, 10.5; 95% confidence interval, 1.4-78.3).

CONCLUSIONS

Pancreatic duct stenting protects significantly against post-ERCP pancreatitis in patients with pancreatic sphincter hypertension undergoing biliary sphincterotomy. Stenting of the pancreatic duct should be strongly considered after biliary sphincterotomy for sphincter of Oddi dysfunction; pancreatic sphincter of Oddi manometry identifies which high-risk patients may benefit from pancreatic stenting.

Diagnosis and treatment of sphincter of Oddi dysfunction

BACKGROUND Sphincter of Oddi dysfunction is a challenge from both the diagnostic and therapeutic point of view. There is much ongoing debate about the accuracy and usefulness of various diagnostic tests, as there is about the effectiveness of proposed therapeutic alternatives.

METHODS

A comprehensive review of the past 15 years' literature was undertaken, using the Medline database and cross-referencing of major articles on the subject.

RESULTS AND CONCLUSION

Endoscopic and surgical treatments result in similar outcomes, with considerable failure rates. The latter reflect the difficulties in accurate diagnosis and a lack of sound objective criteria for selecting patients for intervention. In addition, in some patients sphincter of Oddi dysfunction may be only part of a generalized motility disorder of the gastrointestinal tract.

Sphincter of Oddi dysfunction

Evidence continues to accumulate indicating that sphincter of Oddi dysfunction may give rise to cholestasis, pancreatitis, or upper abdominal pain syndromes. Diagnosis of such dysfunction may be inferred from noninvasive tests or more precisely defined by manometric studies. Both the biliary and pancreatic sphincters are commonly involved. If medical therapy is ineffective, sphincter ablation via endoscopy or laparotomy should be considered for highly symptomatic patients. Complication rates of invasive techniques remain relatively high and risk:benefit ratio should be carefully considered. Future research as to etiology, more defined pathophysiology, more accurate noninvasive evaluation, and optimal therapies are awaited.

Motility of Oddi's sphincter: recent developments and clinical applications

BACKGROUND

In recent years, applications of electromyographic, cineradiographic, scintilographic, and endoscopic manometric techniques have improved our knowledge of normal and abnormal motility of Oddi's sphincter. This sphincter coordinates the time and rate of secretion of about 3 liters of bile and pancreatic juice into the duodenum daily.

METHODS

Oddi's sphincter may be evaluated by endoscopic manometry, ultrasound, dynamic hepatobiliary scintigraphy, and laboratory tests. Endoscopic manometry is the best method for evaluating the function Oddi's sphincter.

RESULTS

The basal pressure of Oddi's sphincter is usually 5 to 15 mm Hg greater than the bile and pancreatic duct pressures. Phasic contractions of 50 to 150 mm Hg in amplitude and 3 to 8 contractions per minute in frequency are superimposed on the basal pressure. A small percentage of patients with gastrointestinal symptoms after cholecystectomy has sphincter of Oddi dysfunction, which may have structural abnormality (papillary stenosis) or functional abnormality (Oddi's sphincter dyskinesia).

CONCLUSIONS

Elevated basal pressure ( > 40 mm Hg) is the most important manometric finding of Oddi's sphincter dysfunction. Endoscopic sphincterotomy is the treatment of choice for patients with Oddi's sphincter dysfunction and elevated basal sphincter pressure.

Endoscopic management of recurrent and chronic pancreatitis

Endoscopic therapy is now being utilized in the setting of recurrent acute and chronic pancreatitis. This review analyzes the current state of the art of these new applications of endoscopy. Selection of appropriate candidates for the various treatment modalities appears important for optimal results of therapy. Patients with gallstone pancreatitis, pancreas divisum, obstructing main pancreatic duct stones, and bulging pseudocysts appear to be the best candidates for endoscopic therapy.