Secretin-stimulated magnetic resonance pancreaticogram to assess pancreatic duct outflow obstruction in evaluation of idiopathic acute recurrent pancreatitis: a pilot study

EUS is superior to secretin-enhanced cholangio-MRI to establish the etiology of idiopathic acute pancreatitis

Background and study aims  The etiology of idiopathic acute pancreatitis (IAP) should always be defined. Our aim was to compare the diagnostic value of endoscopic ultrasound (EUS) versus secretin-enhanced magnetic resonance cholangiopancreatography (S-MRCP) in patients with IAP. Patients and Methods  Patients admitted to a single tertiary care University hospital with IAP were invited to participate in the study. Enrolled patients underwent EUS and S-MRCP in a single-blinded comparative study. EUS and S-MRCP were performed no sooner than 4 weeks after discharge. The diagnostic yield of EUS and S-MRCP and demographic variables were included in the analysis. Additional follow-up, results of subsequent serology, radiographic exams, and relevant histological analysis were considered in determination of the final diagnosis. Results  A total of 34 patients were enrolled; EUS was normal in six, cholelithiasis was defined in 15, choledocholithiasis in two, pancreas divisum in three, branch-type intraductal papillary mucinous tumor (IPMT) in three, and chronic pancreatitis in five. S-MRCP identified choledocholithiasis in one, divisum in four, branch-type IPMT in three, chronic pancreatitis in two; 24 subjects diagnosed as normal by S-MRCP. Diagnostic correlation between EUS and S-MRCP was slight (kappa = 0.236, 95 % confidence interval: 0.055-0.416). EUS provided a statistically significantly higher diagnostic yield than S-MRCP: 79.4 % (CI95 %: 65 %-94 %) vs 29.4 % (CI95 %: 13 %-46 %) (P = 0.0002). The sensitivity, specificity, and positive and negative predictive values of EUS and S-MRCP were 90 %, 80 %, 96 %, 57 % and 33 %, 100 %, 100 % and 16 %, respectively. Conclusion  The diagnostic yield of EUS is higher than S-MRCP in patients with IAP.

Comparison of EUS with MRCP in idiopathic acute pancreatitis: a systematic review and meta-analysis

BACKGROUND AND AIMS

Idiopathic acute pancreatitis (IAP) poses a diagnostic challenge for gastroenterologists, because confirmation of the disease etiology has important implications for the selection of the best possible treatment and the prevention of possible recurrence or the development of chronic pancreatitis (CP). ERCP, EUS, and MRCP typically are used to diagnose IAP when conventional radiologic methods fail. However, their exact role in the diagnosis of IAP has not yet been determined.

METHODS

We searched the PubMed, EMBASE, OVID, Cochrane Library (including CENTRAL), China National Knowledge Infrastructure (CNKI), and Wanfang databases from inception to April 2017. Studies involving the use of EUS and/or MRCP for the etiologic diagnosis of IAP were included. A meta-analysis was performed by using Review Manager Version 5.2 for comparative studies and R software 3.3.3 to determine diagnostic yield of the studies.

RESULTS

Among the 34 studies that met the inclusion criteria (n = 2338), 7 studies used a combination of EUS and MRCP and totaled 249 patients. The results comparing EUS with MRCP showed a diagnostic yield of 153 of the 239 patients (64%) in the EUS group, which was higher than the yield of 82 of 238 patients (34%) in the MRCP group (P < .001) in the 7 studies, and the diagnostic yield was 60% in the EUS group, 24% in the MRCP group, and 43% in the MRCP after secretin stimulation (S-MRCP) group. In our subgroup analysis of CP and biliary disease, EUS was superior to MRCP (P < .001), but when comparing the efficacy of the modalities in the diagnosis of pancreatic divisum, S-MRCP was obviously superior to MRCP and EUS (12% vs 2% vs 2%).

CONCLUSION

EUS and MRCP should both be used in the diagnostic work-up of IAP as complementary techniques. EUS had a higher diagnostic accuracy than MRCP (64% vs 34%) in the etiologic diagnosis of IAP and should be preferred for establishing a possible biliary disease and CP diagnosis, whereas S-MRCP was superior to EUS and MRCP in diagnosing a possible anatomic alteration in the biliopancreatic duct system, such as pancreatic divisum.

The Value of Secretin-Enhanced MRCP in Patients With Recurrent Acute Pancreatitis

OBJECTIVE

The purpose of this study is to assess the additional value of secretin-enhanced MRCP over conventional (non-secretin-enhanced) MRCP in diagnosing disease in patients with recurrent acute pancreatitis.

MATERIALS AND METHODS

A retrospective review of a radiology database found 72 patients with recurrent acute pancreatitis who had secretin-enhanced MRCP and ERCP correlation within 3 months of each other between January 2007 and December 2011. Of these patients, 54 had no history of pancreatic tumor or surgery and underwent MRI more than 3 months after an episode of acute pancreatitis. In addition, 57 age- and sex-matched control subjects with secretin-enhanced MRCP and ERCP correlation and without a diagnosis of recurrent acute pancreatitis or chronic pancreatitis were enrolled as the control group. All studies were anonymized, and secretin-enhanced MRCP images (image set A) were separated from conventional 2D and 3D MRCP and T2-weighted images (image set B). Image sets A and B for each patient were assigned different and randomized case numbers. Two blinded reviewers independently assessed both image sets for ductal abnormalities and group A image sets for exocrine response to secretin.

RESULTS

There were statistically significantly more patients with recurrent acute pancreatitis with reduced exocrine function compared with patients in the control group (32% vs 9%; p < 0.01) on secretin-enhanced images. Patients with recurrent acute pancreatitis were more likely to have side branch dilation (p = 0.02; odds ratio, 3.6), but not divisum, compared with the control group. Secretin-enhanced images were superior to non-secretin-enhanced images for detecting ductal abnormalities in patients with recurrent acute pancreatitis, with higher sensitivity (76% vs 56%; p = 0.01) and AUC values (0.983 vs 0.760; p < 0.01).

CONCLUSION

Up to one-third of patients with recurrent acute pancreatitis showed exocrine functional abnormalities. Secretin-enhanced MRCP had a significantly higher yield for ductal abnormalities than did conventional MRI and should be part of the MRCP protocol for investigation of patients with recurrent acute pancreatitis.

Secretin-Stimulated Magnetic Resonance Imaging Assessment of the Benign Pancreatic Disorders: Systematic Review and Proposal for a Standardized Protocol

This systemic review summarizes the current literature and general consensus on secretin-stimulated magnetic resonance imaging (s-MRI) of the benign pancreatic disorders and discusses important aspects on how s-MRI is optimally performed. The aim is to provide an overview, for clinicians and radiologist, of the s-MRI protocols and the range of clinical applications. Furthermore, the review will summarize the criteria for evaluation of pancreatic morphology and function based on s-MRI.The literature search indentified 69 original articles and 15 reviews. Chronic pancreatitis was the disease that was most frequently assessed by s-MRI (33%), followed by acute pancreatitis (9%). Dynamic thick-slab 2-dimensional magnetic resonance cholangiopancreatography was the most used imaging sequence (86%). The diameter of the main pancreatic duct (75%) and pancreatic exocrine function based on visual grading of duodenal filling (67%) were the most evaluated pancreatic features. Sufficient similarities between studies were identified to propose the most agreeable standardized s-MRI protocol for morphological and functional assessment of the pancreas. In the future, more research and increased collaboration between centers is necessary to achieve more consensus and optimization of s-MRI protocols.

Comparing the Roles of EUS, ERCP and MRCP in Idiopathic Acute Recurrent Pancreatitis

Acute recurrent pancreatitis (ARP) is defined as more than two attacks of acute pancreatitis with complete or almost complete resolution of symptoms and signs of pancreatitis between episodes. The initial evaluation fails to detect the cause of ARP in 10%–30% of patients, whose condition is classified as idiopathic ARP. Endoscopic ultrasound (EUS) has gained increasing attention as a useful imaging modality for the pancreas and the extrahepatic biliary tree. The close proximity of the pancreas to the digestive tract allows EUS to obtain detailed images of this organ. This review aims to record pancreaticobiliary endoscopic ultrasound (EUS) and other imaging modalities in the clinical management of patients with idiopathic ARP.

Endoscopic Treatment of Recurrent Acute Pancreatitis and Smoldering Acute Pancreatitis

Recurrent acute pancreatitis (RAP) is a challenging condition that can lead to chronic pancreatitis and long-term morbidity. Etiology-based treatment can potentially have an impact on the natural history of RAP and its progression to chronic pancreatitis. In cases of divisum-associated RAP and idiopathic RAP, several studies have been performed to evaluate the efficacy of endoscopic therapy in alleviation of symptoms and frequency of AP events. This review discusses the literature available on these topic as well as touching on the role of endoscopic therapy in smoldering acute pancreatitis.

Acute pancreatitis: pancreas divisum with ventral duct intraductal papillary mucinous neoplasms

Acute recurrent pancreatitis occurs rarely in individuals with pancreas divisum. A 39-year-old woman with no significant history presented with pancreatitis. CT scan and MRI suggested acute on chronic pancreatitis with calcifications and pancreatic divisum. An endoscopic ultrasound demonstrated complete pancreas divisum. A large calcification measuring 12 mm × 6 mm was seen in the head of the pancreas with associated dilation of the ventral pancreatic duct. Fine-needle aspiration of the dilated ventral pancreatic duct showed an amylase level of 36,923 U/L and a carcinoembryonic antigen of 194. A ventral duct intraductal papillary mucinous neoplasm was suspected and a pancreaticoduodenectomy procedure was recommended. After the procedure, pathology demonstrated an intraductal papillary lesion in the main duct with moderate dysplasia. A pancreatic intraepithelial neoplasia, grade 2 was also present. Margins of resection were clear. This case represents the importance of assessing for secondary causes of pancreatitis in pancreas divisum.

Secretin-enhanced MR cholangiopancreatography: spectrum of findings

Magnetic resonance cholangiopancreatography (MRCP) is the most effective, safe, noninvasive magnetic resonance (MR) imaging technique for the evaluation of the pancreaticobiliary ductal system. The MRCP imaging technique has substantially improved during the past 2 decades and is based mainly on the acquisition of heavily T2-weighted MR images, with variants of fast spin-echo sequences. MRCP can also be performed by utilizing the hormone secretin, which stimulates a normal pancreas to secrete a significant amount of fluid while transiently increasing the tone of the sphincter of Oddi. The transient increase in the diameter of the pancreatic duct improves the depiction of the ductal anatomy, which can be useful in patients in whom detailed evaluation of the pancreatic duct is most desired because of a suspicion of pancreatic disease. Improved depiction of the ductal anatomy can be important in (a) the differentiation of side-branch intraductal papillary mucinous neoplasms from other cystic neoplasms and (b) the diagnosis and classification of chronic pancreatitis, the disconnected pancreatic duct syndrome, and ductal anomalies such as anomalous pancreaticobiliary junction and pancreas divisum. In patients examined after pancreatectomy, stimulation with secretin can give information about the patency of the pancreaticoenteric anastomosis. Duodenal filling during the secretin-enhanced phase of the MRCP examination can be used to estimate the excretory reserve of the pancreas. Secretin is well tolerated, and complications are rarely seen. Secretin-enhanced MRCP is most useful in (a) the evaluation of acute and chronic pancreatitis, congenital variants of the pancreaticoduodenal junction, and intraductal papillary mucinous neoplasms and (b) follow-up of patients after pancreatectomy.

Dynamic changes of echogenicity and the size of the papilla of Vater before and after cholecystectomy

This study investigated the changes in echogenicity, as measured by endoscopic ultrasound, and the surface area of the papilla of Vater (PV) and their relationship with postoperative symptoms in a group of 80 patients with symptomatic gallstones before and at 3 and 6 months after cholecystectomy. After cholecystectomy, 50 patients experienced early atypical symptoms characteristic of postcholecystectomy syndrome (PCS) and 30 patients were asymptomatic. The surface area of the PV was larger than normal prior to surgery and increased after surgery. The healthy PV is isoechogenic, but 48% of all patients were anisoechogenic preoperatively, increasing to 61% at 3 months after surgery, and decreasing to 25% at 6 months postsurgery. There was no significant difference between the two patient groups, suggesting that the changes observed in the PV do not explain the presence of the atypical symptoms of PCS.

Prospective comparison of endoscopic ultrasonography and magnetic resonance cholangiopancreatography in the etiological diagnosis of "idiopathic" acute pancreatitis

OBJECTIVES

The objectives of the study were to compare endoscopic ultrasonography (EUS) and magnetic resonance cholangiopancreatography (MRCP) in the etiological diagnosis of patients initially diagnosed with idiopathic acute pancreatitis and to determine the clinical and analytical factors related to the end result of these techniques.

METHODS

Forty-nine patients, initially diagnosed with idiopathic acute pancreatitis, were evaluated prospectively with EUS and MRCP. Diagnoses were compared between the 2 procedures. The clinical-evolutionary characteristics of these patients with regard to the results obtained with these techniques were compared.

RESULTS

In twenty-eight patients (57%), EUS and/or MRCP diagnosed at least 1 possible cause of acute pancreatitis. The diagnostic yield of EUS was higher than that of MRCP (51% vs 20%; P = 0.001). Cholelithiasis and biliary sludge (24%) were the most frequent EUS diagnoses, and pancreas divisum (8%) was the most frequent MRCP diagnosis. Only in 3 cases (6%) did MRCP identify additional features in patients etiologically undiagnosed using EUS. The EUS yield was lower in patients who had a previous cholecystectomy (11% vs 60%; P = 0.008).

CONCLUSIONS

Endoscopic ultrasonography and MRCP are useful techniques in the etiological diagnosis of acute pancreatitis of nonestablished cause. Endoscopic ultrasonography should be preferred for establishing a possible biliary etiology in patients who have not had a cholecystectomy.

Diagnostic yield and reliability of endoscopic ultrasonography in patients with idiopathic acute pancreatitis

OBJECTIVES

To evaluate the diagnostic yield of endoscopic ultrasonography (EUS) in patients with idiopathic acute pancreatitis (IAP), find factors predictive of a positive EUS finding in these patients and investigate whether these etiological findings are maintained during follow-up.

MATERIAL AND METHODS

We performed EUS in patients with IAP between July 2004 and August 2007. We recorded epidemiological data, the number and severity of previous bouts of pancreatitis and gallbladder status.

RESULTS

A total of 44 patients were included in the study. EUS was normal in seven patients (16%). In the remaining 37 patients (84%) we found cholelithiasis (n = 3), microlithiasis (n = 20), chronic pancreatitis (n = 14), pancreas divisum (n = 3), pancreatic mass (n = 1), apudoma (n = 1), cystic tumor of the pancreas (n = 2) and choledocholithiasis (n = 2). Positive EUS findings were not influenced by sex, severity of pancreatitis or recurrent disease. Patients aged < 65 years (age > or < 65 years: 73.9% versus 95.2%; P = 0.097) and patients with gallbladder in situ (cholecystectomy versus non-cholecystectomy: 63.6% versus 90.9%; P = 0.054) showed a tendency to have positive EUS findings. Mean follow-up was 28.95 +/- 10.86 months (range 12-64 months; median 28 months). During follow-up the etiological diagnosis was changed in two patients, lowering the diagnostic yield to 79%.

CONCLUSIONS

EUS identified the cause of IAP in 79% of patients. Patients with gallbladder in situ and patients aged < 65 years showed a tendency to have positive EUS findings. The majority of the diagnoses provided by EUS are maintained during follow-up and seem to be reliable.

Diagnostic yield of ERCP and secretin-enhanced MRCP and EUS in patients with acute recurrent pancreatitis of unknown aetiology

BACKGROUND

Magnetic resonance cholangio-pancreatography (MRCP), endoscopic ultrasonography (EUS), and endoscopic cholangio-pancreatography (ERCP) are the most frequently employed second-step procedures to detect biliary and pancreatic abnormalities in patients with acute recurrent pancreatitis (ARP) of unknown aetiology. MRCP and EUS both give a better view of the bilio-pancreatic ductal system after secretin stimulation (MRCP-S, EUS-S). EUS also serves to identify changes in the pancreatic parenchyma consistent with chronic pancreatitis, at an early stage. However, no studies have compared MRCP-S, EUS-S, and ERCP in the diagnosis of recurrent pancreatitis.

AIM

To prospectively compare the diagnostic yield of MRCP-S, EUS-S, and ERCP in the evaluation of patients with acute recurrent pancreatitis with non-dilated ducts, of unknown aetiology.

METHODS

Forty-four consecutive patients with ARP were prospectively scheduled to undergo MRCP-S, EUS-S and ERCP, in accordance with a standard protocol approved by the institutional review board. Diagnoses such as biliary microlithiasis, congenital variants of the pancreatic ducts, chronic pancreatitis and sphincter of Oddi dysfunction were compared between the three procedures. The diagnosis of chronic pancreatitis was established according to ductal morphology by MRCP-S and ERCP, ductal and parenchymal morphology by EUS-S.

RESULTS

The three procedures combined achieved a diagnosis that could have explained the recurrence of pancreatitis in 28/44 patients (63.6%). EUS-S recognized ductal and/or parenchymal abnormalities with the highest frequency (35/44 patients, 79.5%). Both MRCP-S and EUS-S were superior to ERCP for detecting pancreatic ductal abnormalities. EUS-S showed up pancreatic parenchymal changes in more than half the cases. Both EUS and MRCP secretin kinetics were concordant in identifying two cases with sphincter of Oddi dysfunction.

CONCLUSIONS

The diagnostic yield of EUS-S in recurrent pancreatitis with non-dilated ducts and unknown aetiology was 13.6% and 16.7% higher than MRCP-S and ERCP respectively (although not significant), which both gave substantially similar diagnostic yields. In no case did ERCP alone find a diagnosis missed by the other two procedures. MRCP-S and EUS-S should both be used in the diagnostic work-up of idiopathic recurrent pancreatitis as complementary, first-line, techniques, instead of ERCP.

Pancreatic ductal abnormalities documented by secretin-enhanced MRCP in asymptomatic subjects with chronic pancreatic hyperenzymemia

OBJECTIVES

Persistently high serum pancreatic enzymes in asymptomatic subjects are considered a benign idiopathic condition called "non-pathological chronic pancreatic hyperenzymemia" (CPH). However, recent studies with advanced imaging techniques have brought to light abnormal pancreatic findings in a significant proportion of these subjects. The objective of this study was to evaluate pancreatic ductal morphology by secretin-enhanced magnetic resonance cholangiopancreatography (MRCP-S) in subjects with CPH and compare MRCP imaging before and after secretin injection.

METHODS

In total, 25 consecutive patients with CPH were investigated by MRCP and MRCP-S and compared with 28 consecutive age-matched controls with recurrent upper abdominal pain and normal pancreatic enzymemia.

RESULTS

MRCP-S showed abnormal pancreatic morphological findings in 13 of the 25 CPH cases (52%) and 1/28 controls (3.6%) (P<0.001). MRCP findings consistent with a diagnosis of chronic pancreatitis, according to the Cambridge classification, were detected in eight CPH cases (32%) after secretin injection but none of the controls. Secretin stimulation boosted the diagnostic yield of MRCP for the diagnosis of chronic pancreatitis fourfold. Pancreas divisum was identified in two CPH cases and one control. A 15-min persisting dilation of the main pancreatic duct was noted in three cases in each group. Compared with MRCP, MRCP-S showed significantly fewer CPH patients with normal findings (P<0.02).

CONCLUSIONS

MRCP-S detected ductal findings consistent with chronic pancreatitis in one-third of CPH cases. Pancreas divisum and some dysfunction at the level of Vater's papilla were reported in 8 and 12% of the patients, respectively. MRCP-S is to be recommended, instead of MRCP, in the diagnostic work-up of CPH subjects.

MRCP-secretin test-guided management of idiopathic recurrent pancreatitis: long-term outcomes

BACKGROUND

In patients with recurrent pancreatitis of unknown etiology and nondilated ducts, accurate morphofunctional evaluation of the pancreaticobiliary ductal system and sphincter of Oddi function is important in the diagnostic workup. However, ERCP and sphincter of Oddi manometry may be nondiagnostic and postprocedure complications may be frequent.

OBJECTIVE

Our purpose was to assess the diagnostic accuracy of the magnetic resonance cholangiopancreatography with secretin test (MRCP-S) in patients with recurrent acute pancreatitis of unknown etiology. Accuracy was established on the basis of ERCP findings and a minimum of 24 months' clinical follow-up.

DESIGN

Thirty-seven consecutive patients with intact gallbladder and a nondilated pancreaticobiliary ductal system with nonpathologic EUS findings entered a prospective MRCP-S-guided and ERCP-guided diagnostic and therapeutic study protocol.

RESULTS

Patients were followed up for a mean of 31.3 months (range 26-38 months). MRCP-S identified some pancreatic outflow impairment, suggesting morphofunctional dysfunction of either the major or minor papilla, in 12 of 37 patients (32.4%). The addition of ERCP to MRCP-S did not substantially improve the diagnostic yield for the etiology of recurrent pancreatitis, and 13.6% of cases had mild postprocedure pancreatitis. The S-test was abnormal in 12 of 20 cases (60%) in whom some dysfunction of the sphincter of Oddi or minor papilla was assumed on the basis of follow-up findings. The outcome was successful after biliary or pancreatic sphincterotomy in all patients with an abnormal S-test result. Sensitivity, specificity, and positive and negative predictive values of the S-test for the diagnosis of pancreatic outflow impairment at the major or minor papilla were, respectively, 57.1%, 100%, 100%, and 64%. When the test showed an abnormal result, we were unable to distinguish between biliary and pancreatic segment dysfunction of the sphincter of Oddi.

CONCLUSIONS

In idiopathic recurrent pancreatitis with nondilated ducts, the MRCP-S-guided approach gave diagnostic accuracy comparable to ERCP with regard to morphologic lesions, and it can be used as an alternative, avoiding ERCP-related complications in the diagnostic phase. An abnormal S-test result showed an excellent positive predictive value and somewhat disappointing negative predictive value for sphincter of Oddi or minor papilla dysfunction and for clinical success of therapeutic endoscopic approach.

Comparison of secretin-stimulated magnetic resonance pancreatography and manometry results in patients with suspected sphincter of oddi dysfunction

RATIONALE AND OBJECTIVES

To measure main pancreatic duct diameter (PDD) with magnetic resonance pancreatography (MRP) before and after secretin injection in patients with suspected sphincter of Oddi dysfunction (SOD) and to determine if the diameter change is predictive of sphincter of Oddi manometry (SOM) results.

MATERIALS AND METHODS

We identified all patients during the study period referred for SOM for clinically suspected SOD; patients with an intact sphincter and without contraindication to MRP examination were considered for study entry. Consenting patients underwent MRP, including dynamic imaging of the pancreatic duct after intravenous administration of porcine secretin followed by SOM during endoscopic retrograde cholangiopancreatography. MRP was defined as abnormal when PDD remained increased by > or = 1.0 mm from baseline 15 minutes after secretin injection. SOM was abnormal when basal sphincter pressure (SP) was > or = 40 mm Hg. Mean PDD before and after secretin administration was compared within normal and abnormal SP groups with two-tailed unpaired t-test; the mean difference between baseline and peak PDD and duration of > or = 0.5 mm increase in PDD was compared between groups with two-tailed t-test. P < .05 was considered significant.

RESULTS

Of 70 patients referred for SOM, 30 met all entry criteria, gave consent to participate, and underwent both MRP and SOM. Ten of 30 patients (33%) had normal SP; 20 (67%) were abnormal. PDD increased significantly after secretin injection (normal SP, 1.62 +/- 0.73 to 2.78 +/- 0.77 mm, P < .01; abnormal SP, 1.45 +/- 0.26 to 2.32 +/- 0.75 mm, P < .01). There was no difference between normal and abnormal SP groups in amount of PDD increase (1.15 +/- 0.75 vs. 0.88 +/- 0.72 mm; P = .33) or duration of > or = 0.5 mm increase in PDD (5.28 +/- 8.76 vs. 13.60 +/- 13.00 minutes; P = 0.07).

CONCLUSIONS

In patients with suspected sphincter of Oddi dysfunction, magnetic resonance pancreatography demonstrated PDD increase following secretin injection but did not predict the results of manometry.

Diagnostic approach to patients with acute idiopathic and recurrent pancreatitis, what should be done?

Acute recurrent pancreatitis (ARP) is a common clinical condition that may be difficult to diagnose. Endoscopic ultrasound (EUS) is proposed to be a safe first line test of choice in the majority of patients. When interventions are needed to remove biliary stones, evaluate sphincter of Oddi or pancreas divisum, endoscopic retrograde cholangiopancreatography (ERCP) is recommended. Magnetic resonance cholangiopancreatography (MRCP) can be a suitable alternative from a diagnostic standpoint although may not be widely available. Finally, genetic testing is increasingly used to detect certain mutations that are associated with this diagnosis.

Technology insight: applications of MRI for the evaluation of benign disease of the pancreas

This article reviews the role of MRI in the evaluation of benign pancreatic disease. Although MRI and magnetic resonance cholangiopancreatography (MRCP) are most often used to evaluate the liver and bile duct, technical advances such as the use of secretin stimulation also allow for high-quality imaging of the pancreas and pancreatic ductal system. Secretin-stimulated MRCP (S-MRCP) can aid the diagnosis of acute and chronic pancreatitis, and delineate ductal pathology such as benign strictures and duct leaks. There seems to be a role for S-MRCP in the assessment of pancreatic function and (possibly) sphincter of Oddi dysfunction. When endoscopic or surgical therapy is planned, S-MRCP can help to establish a diagnosis as well as offer a 'road map' to guide therapy. S-MRCP is noninvasive and almost entirely without risk to the patient, which gives it a distinct advantage over traditional endoscopic methods of diagnosis for conditions such as pancreas divisum and other ductal pathology. The information provided by S-MRCP, obtained before endoscopic or surgical therapy is attempted, can assist the patient and physician in making a fully informed decision with regard to the risks and probable benefits of any planned intervention.

Management of pancreas divisum

Pancreas divisum is the most common congenital anomaly of the pancreas. Abnormal hedgehog protein signaling appears related to the formation of several pancreatic malformations, including annular pancreas, pancreatic-biliary malunion, pancreatic rests, and pancreas divisum. Pancreas divisum by itself should not necessarily require intervention. A careful evaluation should be performed to exclude other causes of symptoms. If the patient is asymptomatic, no further evaluation is necessary. However, a significant percentage of patients with pancreas divisum and acute recurrent pancreatitis benefit from intervention. Surgical sphincteroplasty and endoscopic interventions appear similar in outcome. Thus, endoscopic intervention with prophylactic temporary stenting is advised as initial therapy. Surgery should be reserved for patients with chronic pancreatitis.