Severe chronic pancreatitis versus suspected pancreatic disease: dynamic MR cholangiopancreatography after secretin stimulation

Secretin-enhanced MRCP: review of technique and application with proposal for quantification of exocrine function

OBJECTIVE

The purpose of this article is to present a proposal for quantification of exocrine function using secretin-enhanced MRCP for the diagnosis of chronic pancreatitis. The article also reviews the technique and application of secretin-enhanced MRCP in evaluating various pancreatic abnormalities.

SUBJECTS AND METHODS

One hundred thirty-four consecutive patients with chronic abdominal pain undergoing secretin-enhanced MRCP for suspected chronic pancreatitis were included. Patients were divided into four clinical groups (normal, equivocal, early chronic pancreatitis, established pancreatitis) on the basis of clinical symptoms and additional investigations, including CT (n=98), endoscopic pancreatic function test (n=65), endoscopic ultrasound (n=84), and ERCP (n=36). The volume of secretion was obtained by drawing a region of interest around T2 bright fluid secreted on postsecretin HASTE images. The maximal rate of secretion in response to secretin was obtained by plotting change in signal intensity on sequential postsecretin images. The analysis of variance test was used to compare the clinical groups with the volume and rate of secretion.

RESULTS

Significant volume differences were found between the normal and established pancreatitis groups (p<0.0001) as well as the equivocal and established pancreatitis groups (p<0.0005). Marginally significant differences were found between the normal and early pancreatitis groups (p=0.0150) as well as early and established pancreatitis groups (p=0.0351). Differences in the maximal rate of secretion were not statistically significant.

CONCLUSION

Secretory volume measurement of secretin-enhanced MRCP data is a simple method that brings out significant differences between normal, early, and established pancreatitis patients.

Quantitative MRCP assessment of pancreatic exocrine reserve and its correlation with faecal elastase-1 in patients with chronic pancreatitis

PURPOSE

This retrospective study was done to correlate a quantitative assessment of the pancreatic exocrine reserve by dynamic secretin magnetic resonance cholangiopancreatography (MRCPQ) with the faecal elastase-1 (FE-1) test in patients with chronic pancreatitis.

MATERIALS AND METHODS

Thirty-five patients with a clinical diagnosis of chronic (CP) or acute recurrent (ARP) pancreatitis were enrolled. FE-1 was indicative of the pancreatic exocrine reserve. Subsequently, the patient population was subdivided into two groups according to a clinical threshold value of 200 μg/g. All patients underwent MRCP examination during secretin administration. Duodenal filling volume was calculated on T2-weigthed rapid acquisition with relaxation enhancement (RARE) MRCP images obtained 10 min after secretin injection. Duodenal filling volumes were compared with FE-1 values. Scatter plots, Pearson correlation coefficient and the Mann-Whitney U test were performed.

RESULTS

Thirty-five paired MRCPQ-FE1 data sets were analysed. MRCPQ was significantly different (p=0.007) between patients with impaired and preserved pancreatic function; median and interquartile range (IQR) were 150.7 ml (137.3-205.5 ml; n=9) and 332.4 ml (190.6-506.9 ml; n=26). Both Pearson correlation coefficient (p<0.001) and the Mann-Whitney U test (p=0.007) were significant.

CONCLUSIONS

MRCPQ significantly correlates with FE-1 values. It is possible to discriminate impaired and preserved pancreatic exocrine function using MRCPQ.

Management of mucinous cystic neoplasms of the pancreas

The purpose of this study was to investigate the actual management of mucinous cystic neoplasm (MCN) of the pancreas. A systematic review was performed in December 2009 by consulting PubMed MEDLINE for publications and matching the key words “pancreatic mucinous cystic neoplasm”, “pancreatic mucinous cystic tumour”, “pancreatic mucinous cystic mass”, “pancreatic cyst”, and “pancreatic cystic neoplasm” to identify English language articles describing the diagnosis and treatment of the mucinous cystic neoplasm of the pancreas. In total, 16 322 references ranging from January 1969 to December 2009 were analysed and 77 articles were identified. No articles published before 1996 were selected because MCNs were not previously considered to be a completely autonomous disease. Definition, epidemiology, anatomopathological findings, clinical presentation, preoperative evaluation, treatment and prognosis were reviewed. MCNs are pancreatic mucin-producing cysts with a distinctive ovarian-type stroma localized in the body-tail of the gland and occurring in middle-aged females. The majority of MCNs are slow growing and asymptomatic. The prevalence of invasive carcinoma varies between 6% and 55%. Preoperative diagnosis depends on a combination of clinical features, tumor markers, computed tomography (CT), magnetic resonance imaging, endoscopic ultrasound with cyst fluid analysis, and positron emission tomography-CT. Surgery is indicated for all MCNs.

Italian consensus guidelines for chronic pancreatitis

This paper gives practical guidelines for diagnosis and treatment of chronic pancreatitis. Statements have been elaborated by working teams of experts, by searching for and analysing the literature, and submitted to a consensus process by using a Delphi modified procedure. The statements report recommendations on clinical and nutritional approach, assessment of pancreatic function, treatment of exocrine pancreatic failure and of secondary diabetes, treatment of pain and prevention of painful relapses. Moreover, the role of endoscopy in approaching pancreatic pain, pancreatic stones, duct narrowing and dilation, and complications was considered. Recommendations for most appropriate use of various imaging techniques and of ultrasound endoscopy are reported. Finally, a group of recommendations are addressed to the surgical treatment, with definition of right indications, timing, most appropriate procedures and techniques in different clinical conditions and targets, and clinical and functional outcomes following surgery.

The effect of prior sphincterotomy on the secretin-stimulated magnetic resonance cholangiopancreatography (s-MRCP)

RATIONALE AND OBJECTIVES

A lack of pancreatic duct compliance and decreased duodenal filling on secretin-stimulated magnetic resonance cholangiopancreatography (s-MRCP) has been noted in patients with chronic pancreatitis. Whether endoscopic sphincterotomy can affect pancreatic duct compliance and duodenal filling on diagnostic s-MRCP is unknown.

MATERIALS AND METHODS

A retrospective review of patients referred to the authors' clinic from December 2006 to December 2007 was performed. Those patients with no evidence of chronic pancreatitis who underwent s-MRCP were studied. Findings on s-MRCP were analyzed, specifically noting change in pancreatic duct diameter size from baseline to maximum dilation and duodenal filling after secretin administration (0.2 microg/kg intravenous dose of human secretin).

RESULTS

Of the 34 patients studied, 12 underwent endoscopic sphincterotomy, and 22 had intact sphincters of Oddi. In the sphincterotomy group, there was a mean change of 0.2 cm (range, 0.0-0.4 cm), while in the nonsphincterotomy group, the mean change was 0.9 cm (range, 0.3-2.0 cm) after secretin administration. The difference was significant (P < .005).

CONCLUSION

Endoscopic sphincterotomy significantly decreases pancreatic duct dilation in response to secretin on s-MRCP. However, further studies are required to determine the effect sphincterotomy has on the amount of duodenal filling and the rate at which duodenal filling occurs.

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.

Autoimmune pancreatitis: imaging findings on contrast-enhanced MR, MRCP and dynamic secretin-enhanced MRCP

PURPOSE

This study retrospectively determined magnetic resonance (MR), MR cholangiopancreatography (MRCP) and secretin-MRCP findings in patients with autoimmune pancreatitis (AIP).

MATERIALS AND METHODS

The MR examinations of 28 patients with histopathologically proven AIP were reviewed. In 14 cases, secretin-enhanced MRCP was performed. The observers evaluated pancreatic parenchymal enlargement, signal intensity abnormalities, enhancement, vascular involvement, bile-duct diameter and main pancreatic duct (MPD) narrowing (diffuse/focal/segmental). After secretin administration, the presence of the "duct-penetrating" sign was evaluated.

RESULTS

MR imaging showed diffuse pancreatic enlargement in 8/28(29%) cases, focal pancreatic enlargement in 16/28 (57%) cases and no enlargement in 4/28 (14%) cases. The alteration of pancreatic signal intensity was diffuse in 8/28 (29%) cases (eight diffuse AIP) and focal in 20/28 (71%) cases (20 focal AIP). Delayed pancreatic enhancement was present in all AIP, with peripheral rim of enhancement in 8/28 (29%) AIP (1/8 diffuse, 7/20 focal); vascular encasement was present in 7/28 (25%) AIP (1/8 diffuse, 6/20 focal); distal common bile duct narrowing was present in 12/28(43%) AIP (5/8 diffuse, 7/20 focal). MRCP showed MPD narrowing in 17/28 (61%) AIP (4/8 diffuse, 15/20 focal), MPD dilation in 8/28(29%) AIP (3/8 diffuse, 5/20 focal) and normal MPD in 1/8 diffuse AIP. Secretin-MRCP showed the duct-penetrating sign in 6/14(43%) AIP (one diffuse AIP with MPD segmental narrowing, five focal AIP with MPD focal narrowing), demonstrating integrity of the MPD.

CONCLUSIONS

Delayed enhancement and MPD stenosis are suggestive for AIP on MR and MRCP imaging. Secretin-enhanced MRCP is a problem-solving tool in the differential diagnosis between focal AIP and ductal adenocarcinoma.

The yield of first-time endoscopic ultrasonography in screening individuals at a high risk of developing pancreatic cancer

OBJECTIVES

Approximately 10-15% of all pancreatic cancers (PCs) may be hereditary in origin. We investigated the use of endoscopic ultrasonography (EUS) for the screening of individuals at high risk for developing PC. In this paper the results of first-time screening with EUS are presented.

METHODS

Those eligible for screening in this study were first-degree family members of affected individuals from familial pancreatic cancer (FPC) families, mutation carriers of PC-prone hereditary syndromes, individuals with Peutz-Jeghers syndrome, and mutation carriers of other PC-prone hereditary syndromes with clustering (> or =2 cases per family) of PC. All individuals were asymptomatic and had not undergone EUS before.

RESULTS

Forty-four individuals (M/F 18/26), aged 32-75 years underwent screening with EUS. Thirteen were from families with familial atypical multiple-mole melanoma (FAMMM), 21 with FPC, 3 individuals were diagnosed with hereditary pancreatitis, 2 were Peutz-Jeghers patients, 3 were BRCA1 and 2 were BRCA2 mutation carriers with familial clustering of PC, and 1 individual had a p53 mutation. Three (6.8%) patients had an asymptomatic mass lesion (12, 27, and 50 mm) in the body (n=2) or tail of the pancreas. All lesions were completely resected. Pathology showed moderately differentiated adenocarcinomas with N1 disease in the two patients with the largest lesions. EUS showed branch-type intraductal papillary mucinous neoplasia (IPMN) in seven individuals.

CONCLUSIONS

Screening of individuals at a high risk for PC with EUS is feasible and safe. The incidence of clinically relevant findings at first screening is high with asymptomatic cancer in 7% and premalignant IPMN-like lesions in 16% in our series. Whether screening improves survival remains to be determined, as does the optimal screening interval with EUS.

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.

Diagnosis of chronic pancreatitis by using apparent diffusion coefficient measurements at 3.0-T MR following secretin stimulation

PURPOSE

To prospectively measure pancreatic apparent diffusion coefficient (ADC) before and after secretin administration in subjects with and without chronic pancreatitis (CP) who underwent magnetic resonance (MR) cholangiopancreatography with diffusion-weighted (DW) imaging at 3.0 T.

MATERIALS AND METHODS

Institutional review board approval of this HIPAA-compliant study was obtained. Healthy volunteers, and patients with suspected and/or known CP who were scheduled for MR cholangiopancreatography, were recruited and gave written informed consent. All subjects underwent 3.0-T MR cholangiopancreatography, including serial DW imaging sequences (b = 0, 200, and 400 sec/mm(2)) acquired for 15 minutes after secretin administration. The referring gastroenterologist then classified subjects as healthy or with mild or severe CP, given endoscopic retrograde cholangiopancreatographic and/or clinical findings. CP severity was analyzed for sex and age. Mean presecretin and maximum postsecretin ADCs were compared between groups. Pairwise mean ADCs for healthy versus mild CP patient groups, healthy versus severe CP patient groups, and mild versus severe CP patient groups were compared. Presecretin ADC threshold levels for CP discrimination were calculated (P < .05).

RESULTS

Thirty-two subjects were imaged; four CP patients were excluded owing to severe artifact, and the remaining 28 (15 healthy patients, five with mild CP, and eight with severe CP) comprised the study population. All CP patients had endoscopic retrograde cholangiopancreatographic confirmation of CP. Mild or severe CP patients were older than healthy patients; sex distribution did not vary among groups. Mean presecretin and maximum postsecretin ADCs were higher in healthy patients than in either mild or severe CP groups (P < .01), but did not vary between mild and severe CP groups (P = .25-0.28). An ADC of less than 220 x 10(-5) mm(2)/sec was optimal for delineating between healthy and CP patients.

CONCLUSION

Pancreatic ADC obtained with DW imaging at 3.0 T prior to secretin administration may help diagnose CP; postsecretin ADC response does not distinguish CP severity.

Orally administered lemon/orange juice improved MRCP imaging of pancreatic ducts

BACKGROUND

The aim of this study was to determine the effectiveness of oral administration of lemon/orange juice in improving the visualization of pancreatic ducts on MRCP.

MATERIALS AND METHODS

MRCP images were generated before and at every 15 min for 90 min after oral administration of lemon/orange juice in a dose of 2 ml/kg in 20 volunteers and 26 patients. The pre- and post-administration images were compared and analyzed qualitatively and quantitatively.

RESULTS

In 20 volunteers and 26 patients, the visualization at pancreatic duct of head, body, tail, accessory pancreatic duct, and branch duct was improved after juice administration. The diameter of pancreatic ducts was augmented, and the differences in the mean values before and after oral juice were highly significant at both sites in volunteers and patients (P < 0.01). In 20 volunteers and 26 patients, after juice administration, the best visualization of the pancreatic duct was achieved at (58.98 +/- 14.96) min and (59.41 +/- 13.79) min, respectively, and the overlap imaging of oral juice was especially observed at (42.86 +/- 10.92) min and (41.63 +/- 9.32) min, respectively.

CONCLUSIONS

Orally lemon/orange juice is an effective method to improve MRCP imaging of pancreatic ducts. The lemon/orange juice should be administered at 60 min prior to MRCP.

Calibrated magnetic resonance hydrometry to quantify pancreatic juice: a preliminary study

PURPOSE

To investigate the effectiveness of the calibrated MR hydrometry (CMRH) method for accurately measuring pancreatic secretion.

MATERIALS AND METHODS

All studies were performed on a 1.5-T MR system using a fat-suppressed, single-shot half-Fourier fast spin-echo sequence with a standard body coil. A certain volume (20 mL) of saline solution was employed as an extrabody calibrator. The validity of the CMRH method was tested both in vitro and in vivo, and actual and calculated volumes were compared.

RESULTS

The in vitro study yielded a high correlation (r = 0.99; P < 0.0001) between the actual volume of saline solution in the imaging field and the calculated volume. In the in vivo study, for all volunteers, there was a very strong and significant positive correlation between the measured signal intensities or calculated volumes and actual volumes (correlation coefficient range: 0.94-0.99; P < 0.0001).

CONCLUSION

This preliminary study shows that CMRH is an effective tool to measure the amount of pancreatic fluid secretion.

Imaging of the pancreas with secretin enhancement

Magnetic resonance cholangiopancreatography is a noninvasive imaging technique for evaluation of the pancreatic duct and the biliary tree. Secretin is a polypeptide hormone that has numerous physiological effects, including stimulation of the pancreatic secretion of bicarbonate-rich fluid and transient increase in the tone in the sphincter of Oddi. As a result, secretin administration usually results in distention of the pancreatic duct; therefore, visualization of the pancreatic ductal anatomy is often substantially improved. Awareness of its value by referring clinicians and radiologists will increase its use in the future.

Sonographic assessments of gastrointestinal and biliary functions

Ultrasound has been established as a routine work-up imaging method in abdominal diseases. It assesses the morphology of intra-abdominal organs and depicts the normal and pathological anatomy of the gastrointestinal tract as well as of the biliopancreatic system. Ultrasound is the method of choice for visualisation of motion sequences since it is, in contrast to other imaging methods, a real-time method. The non-invasiveness and the repeatability of the method are important advantages when performing investigations of functional processes. Therefore, ultrasound is most suited for functional studies. Up to now, functional ultrasound and its potential have been undervalued. Functional ultrasound provides a widely available method to increase our understanding of functional processes and motility. The authors review the options of functional ultrasound and discuss its practical relevance.

Morphological and functional evaluation of the pancreatic duct with secretin-stimulated magnetic resonance cholangiopancreatography in alcoholic pancreatitis patients

OBJECTIVES

The aim of this investigation was to evaluate the pancreatographic findings and dynamics of pancreatic duct diameter, as determined by secretin-enhanced magnetic resonance cholangiopancreatography (S-MRCP), in patients with acute alcoholic pancreatitis or chronic alcoholic pancreatitis and in a control group.

METHODS

S-MRCP was performed in patients with acute alcoholic pancreatitis who did not manifest the functional and radiological (ultrasonography and computed tomography) criteria of chronic pancreatitis (n = 21), in patients with chronic alcoholic pancreatitis (n = 28) and in a control group (n = 16). The diameter of the main pancreatic duct (MPD) was monitored before secretin administration and at 3 and 10 min after secretin administration. Morphological features were also assessed before and after the administration of secretin.

RESULTS

All ductal diameters were significantly larger in chronic alcoholic pancreatitis (P < 0.0001). There were no differences in MPD caliber between patients with acute alcoholic pancreatitis and the control group. The percentage of variation between basal MPD diameter and at 3 min post-secretin administration was lower in patients with chronic (35.5%) pancreatitis than in those with acute alcoholic pancreatitis (52.3%) and the control group (52.5%). There were no significant differences between patients with acute alcoholic pancreatitis and the control group in terms of the frequency of visualization of side branches, ductal narrowing, intraluminal filling defects, and ductal irregularity. One patient with acute alcoholic pancreatitis presented ductal criteria of chronic pancreatitis following the administration of secretin.

CONCLUSIONS

The dynamics of MPD visualized on S-MRCP in patients with acute alcoholic pancreatitis is similar to that observed in the control group and different from that observed in patients with chronic alcoholic pancreatitis. There were no significant differences between patients with acute alcoholic pancreatitis and the control group in terms of morphological pancreatographic features.

Assessment of chronic pancreatitis: utility of diffusion-weighted MR imaging with secretin enhancement

PURPOSE

To retrospectively measure and compare changes in pancreatic apparent diffusion coefficient (ADC) following secretin administration in patients with and those without chronic pancreatitis (CP) who underwent magnetic resonance (MR) cholangiopancreatography with diffusion-weighted (DW) imaging.

MATERIALS AND METHODS

This retrospective HIPAA-compliant study was approved by the authors' institutional review board, with waiver of informed consent. Eighty-nine patients were categorized by the referring gastroenterologist as having no CP (n = 37), mild CP (n = 33), or severe CP (n = 19) on the basis of Cambridge criteria and/or clinical course. Mean age was 52.2 years (range, 21-82 years) in women and 54.3 years (range, 32-81 years) in men. Patients underwent 1.5-T MR cholangiopancreatography, including DW sequences (b = 0, 100, and 400 sec/mm(2)) performed serially for 10 minutes after secretin injection. Severity level of CP was analyzed for sex (Fisher exact test) and age (analysis of variance) differences. Pairwise comparisons of mean ADCs for each parameter (no CP vs mild CP, no CP vs severe CP, mild CP vs severe CP) were performed (Mann-Whitney test). Threshold values of non-secretin-enhanced ADC for pancreatitis discrimination were calculated with receiver operating characteristic analysis. P < .05 was considered to show a significant difference.

RESULTS

Patients with severe CP were more likely to be men than were those without pancreatitis; there were no significant age differences between groups. Mean nonenhanced and maximum secretin-enhanced ADCs were higher in patients without CP than in those with mild or severe CP but did not vary between those with mild and severe CP. Percentage increase in ADC after secretin injection and time to peak ADC did not vary among groups. An ADC of less than 179 x 10(-5) mm(2)/sec was optimal for delineating normal pancreas from CP groups.

CONCLUSION

In symptomatic patients, baseline pancreatic ADC obtained with DW imaging prior to secretin administration may aid in diagnosis of CP and assessment of its severity; ADC response to secretin administration may be less useful.

Prospective evaluation of the diagnostic accuracy of secretin-enhanced magnetic resonance cholangiopancreaticography in suspected chronic pancreatitis

The purpose of this study was to determine the improvement in sensitivity and specificity of magnetic resonance cholangiopancreaticography (MRCP) in the diagnosis of chronic pancreatitis due to the application of secretin. Sixty-two consecutive patients with suspected chronic pancreatitis were prospectively included in our study. All investigations were carried out in a clinical 1.0-T MR-scanner using heavily T2-weighted pre- and dynamic post secretin measurements. Dynamic images were acquired every 30 s for a total imaging time of 10 min. Two experienced radiologists blinded for all other results evaluated the images in random order in two sessions: one for the native images and one for the stimulated MRCP series. The gold standard for the final diagnosis was the summary of all clinical and radiological results. Sensitivity and specificity for the diagnosis of chronic pancreatitis and the kappa coefficient for the agreement between both observers were calculated. Prior to secretin application, investigators achieved sensitivities of 78% and 56%, respectively, and specificities of 89% and 96%, respectively. After secretin application, the sensitivity for the first observer remained at 78%; for the second observer it increased to 67%, whereas specificities improved to 94% and 98%, respectively. Following secretin application, agreement determined between the two investigators improved from 0.73 to 0.84. While MRCP already provides high sensitivity and specificity, application of secretin increases both values and the reliability of the diagnosis further.

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.

Diagnosis of mild chronic pancreatitis (Cambridge classification): Comparative study using secretin injection-magnetic resonance cholangiopancreatography and endoscopic retrograde pancreatography

AIM: To investigate the usefulness of secretin injection-MRCP for the diagnosis of mild chronic pancreatitis.

METHODS: Sixteen patients having mild chronic pancreatitis according to the Cambridge classification and 12 control subjects with no abnormal findings on the pancreatogram were examined for the diagnostic accuracy of secretin injection-MRCP regarding abnormal branch pancreatic ducts associated with mild chronic pancreatitis (Cambridge Classification), using endoscopic retrograde cholangiopancreatography (ERCP) for comparison.

RESULTS: The sensitivity and specificity for abnormal branch pancreatic ducts determined by two reviewers were respectively 55%-63% and 75%-83% in the head, 57%-64% and 82%-83% in the body, and 44%-44% and 72%-76% in the tail of the pancreas. The sensitivity and specificity for mild chronic pancreatitis were 56%-63% and 92%-92%, respectively. Interobserver agreement (κ statistics) concerning the diagnosis of an abnormal branch pancreatic duct and of mild chronic pancreatitis was good to excellent.

CONCLUSION: Secretin injection-MRCP might be useful for the diagnosis of mild chronic pancreatitis.

Pancreatic ductal system obstruction and acute recurrent pancreatitis

Acute recurrent pancreatitis is a clinical entity largely associated with pancreatic ductal obstruction. This latter includes congenital variants, of which pancreas divisum is the most frequent but also controversial, chronic pancreatitis, tumors of the pancreaticobiliary junction and sphincter of Oddi dysfunction. This review summarizes current knowledge about diagnostic work-up and therapy of these conditions.

Radiologic assessment of acute and chronic pancreatitis

The capabilities of various imaging modalities, including CT, MRI, and ultrasound, have markedly increased over recent years. This has translated into improved detection and improved characterization of various pathologic processes. This article discusses the current role of imaging in the evaluation of acute and chronic pancreatitis. CT remains a major focal point in issues related to acute pancreatitis, whereas MRI (and magnetic resonance cholangiopancreatography) plays a larger role in chronic pancreatitis.

MR cholangiopancreatography in children: feasibility, safety, and initial experience

BACKGROUND

The indications for MR cholangiopancreatography (MRCP) in children, and its safety and findings, might differ from those in adults and are not well described.

OBJECTIVE

To investigate the safety, feasibility, and accuracy of MRCP in children.

MATERIALS AND METHODS

We reviewed all prospective MRCP reports, noting the indication, the use of secretin, endoscopic retrograde cholangiopancreatography (ERCP) findings, and patient outcomes. Two readers reviewed each MRCP study by consensus to rate duct visualization and compare pancreatic duct sizes before and after secretin administration (paired t-test). The likelihood of a normal versus an abnormal MRCP study was compared by gender, pancreatitis as the primary indication, secretin use, and whether ERCP was performed (Fisher's exact test), as well as age (t-test).

RESULTS

A total of 85 MRCP studies were performed in children (mean age 10.3 years), most commonly for evaluation of pancreatitis (n=47, 55%); 41 (48%) used secretin and 39 (46%) used a negative oral contrast agent. Of the 85 studies, 72 (85%) had excellent image quality and 43 were normal. ERCP was performed after 16 of the 85 MRCP studies (19%); the diagnoses were concordant with those of MRCP in 13 (81%). There were 42 abnormal MRCP studies, and these were more likely to be in girls (P=0.03) and in children who had undergone ERCP (P<0.01). Secretin and the negative oral contrast agent were well-tolerated. Secretin improved duct visualization (P<0.001).

CONCLUSION

MRCP safely and accurately depicted pancreaticobiliary anatomy in children. The use of secretin improved visualization of the pancreatic duct.

Radiology of pancreatic adenocarcinoma: current status of imaging

Pancreatic adenocarcinoma is one of the leading causes of cancer death in the West, with a poor overall 5-year survival rate of only 4%. Late clinical presentation with an advanced disease results in a low rate of surgical intervention. Tumor serum marker CA 19-9 is sensitive, although not specific for the diagnosis of adenocarcinomas of the pancreas. The treatment approach is based on whether the tumor is resectable or non-resectable at presentation. Therefore, imaging plays a crucial role in the management of this disease. Many modalities are available to image the pancreas. They include non-invasive techniques, like ultrasound, contrast-enhanced multidetector computed tomography, magnetic resonance imaging and integrated positron emission tomography/computed tomography, and invasive techniques, like endoscopic retrograde cholangiopancreatography and endoscopic ultrasound. Each of these modalities has its peculiar strengths and weaknesses.

A retrospective assessment of magnetic resonance cholangiopancreatography in children

OBJECTIVE

To evaluate the utility of magnetic resonance cholangiopancreatography (MRCP) in children and to compare MRCP with direct cholangiopancreatography (CP).

MATERIALS AND METHODS

We performed an unblinded, retrospective chart review of 32 children (ages 0-18 years, 17 male) who underwent MRCP between January 2002 and June 2005. MRCP, endoscopic retrograde cholangiopancreatography (ERCP), percutaneous fluoroscopic or intraoperative studies of the pancreatobiliary tree, and clinical outcomes were evaluated.

RESULTS

Seventeen (52%) children had MRCP alone, 15 (48%) had both MR and direct CP. MRCP results correlated with other evaluative methods in 14/15 (93%) cases. There was 1 false positive (anomalous pancreatic duct union) and 0 false negatives for anatomic abnormalities. Therapeutic intervention was performed in 7 of 28 children initially evaluated by MRCP (2 sphincter of Oddi dysfunction, 2 choledocholithiasis, 2 primary sclerosing cholangitis, 1 congenital hepatic cysts) and 1 of 4 children initially evaluated by ERCP (primary sclerosing cholangitis). All 17 children initially evaluated by MRCP had no change in clinical status to suggest a missed anatomic lesion or therapeutic opportunity.

CONCLUSIONS

In this retrospective study, MRCP was sensitive and specific in identifying anatomic abnormalities of the pancreatobiliary tree in children. MRCP should be considered before direct CP to evaluate anatomic abnormalities of the pancreatobiliary tree.

The use of magnetic resonance cholangiopancreatography in children

Magnetic resonance cholangiopancreatography (MRCP) is a noninvasive method to evaluate a wide variety of pancreatobiliary disorders. These disorders include choledochal cyst, cholelithiasis, choledocholithiasis, biliary atresia, Caroli's disease, primary sclerosing cholangitis, disorders of the pancreatobiliary junction, pancreas divisum, and pancreatic duct abnormalities related to chronic pancreatitis. The use of MRCP in children is increasing as experience with MRCP grows, and its technological accuracy rivals that of endoscopic evaluation. We review the current state of MRCP use in children.

Quantitative secretin MRCP (MRCPQ): results in 215 patients with known or suspected pancreatic pathology

Secretin magnetic resonance cholangiopancreatography quantification (MRCPQ) of pancreatic exocrine function correlates well with steatorrhoea and conventional, non-invasive function tests. We report MRCPQ results in a variety of pancreatic conditions. A total of 215 patients [107 male, mean age 46 years (14-78)] were studied. A multi-slice MRCP sequence was performed before and at 2-min intervals after 0.1 ml/kg IV secretin. Change in small intestinal water volume was plotted against time and the flow rate derived from the gradient. Patients were classified using clinical history, MRCP, MR imaging, computed tomography (CT) [150/215 (70%)] and endoscopic retrograde cholangiopancreatography (ERCP) [56/215 (26%)] findings but not MRCPQ results. Mean, standard deviation and 95% confidence intervals were calculated. The one way ANOVA and Student's t-test were used for statistical analysis. Seventy-six patients had chronic pancreatitis, 26 were post-surgical, 34 post-acute pancreatitis, six atrophic pancreatopathy, eight with obstruction, 15 divisum, ten sphincter of Oddi dysfunction, 26 normal and 14 miscellaneous. Significant differences were observed between normals (mean+/-SD; 7.4 +/- 2.9 ml/min) and severe chronic pancreatitis (5.3 +/- 2.4) (P = 0.018), pancreatic atrophy (3.8 +/- 3.1) (P = 0.013) or duct obstruction (5.3 +/- 2.4) (P = 0.047)) and between moderate (7.0 +/- 3.0) (P = 0.03) and severe chronic pancreatitis. MRCPQ can be used to quantify function across the spectrum of pancreatic disease and showed significant differences between several different pathologies.

Magnetic resonance imaging in the detection of pancreatic neoplasms

Recently, with the rapid scanning time and improved image quality, outstanding advances in magnetic resonance (MR) methods have resulted in an increase in the use of MRI for patients with a variety of pancreatic neoplasms. MR multi-imaging protocol, which includes MR cross-sectional imaging, MR cholangiopancreatography and dynamic contrast-enhanced MR angiography, integrates the advantages of various special imaging techniques. The non-invasive all-in-one MR multi-imaging techniques may provide the comprehensive information needed for the preoperative diagnosis and evaluation of pancreatic neoplasms. Pancreatic neoplasms include primary tumors and pancreatic metastases. Primary tumors of the pancreas may be mainly classified as ductal adenocarcinomas, cystic tumors and islet cell tumors (ICT). Pancreatic adenocarcinomas can be diagnosed in a MRI study depending on direct evidence or both direct and indirect evidence. The combined MRI features of a focal pancreatic mass, pancreatic duct dilatation and parenchymal atrophy are highly suggestive of a ductal adenocarcinoma. Most cystic neoplasms of the pancreas are either microcystic adenomas or mucinous cystic neoplasms. Intraductal papillary mucinous tumors are the uncommon low-grade malignancy of the pancreatic duct. ICT are rare neoplasms arising from neuroendocrine cells in the pancreas or the periampullary region. ICT are classified as functioning and non-functioning. The most frequent tumors to metastasize to the pancreas are cancers of the breast, lung, kidney and melanoma. The majority of metastases present as large solitary masses with well-defined margins.

The M-ANNHEIM classification of chronic pancreatitis: introduction of a unifying classification system based on a review of previous classifications of the disease

BACKGROUND

Several classification systems of chronic pancreatitis have been proposed to provide a basis for treatment and research. All of these previous classifications were designed at the height of pancreatic research of their respective times; thus, each represented the most current knowledge available to pancreatologists at the time. However, none of these classifications provide simultaneously a simple standardized system for the clinical classification of chronic pancreatitis according to etiology, clinical stage, and severity of the disease, nor are they consistently useful for directing clinical practice and comparing interinstitutional data. Thus, we aimed to develop a new classification system of chronic pancreatitis to provide a framework for studying the interaction of various risk factors on the course of the disease.

METHODS

We reviewed the literature on the clinical course of all different forms of chronic pancreatitis, and we reviewed all previous classification systems of the disease. This approach provided a basis for the development of a new and unifying classification of chronic pancreatitis.

RESULTS

We established the M-ANNHEIM multiple risk factor classification system based on the current knowledge of acute and chronic pancreatitis. This classification allows patients to be categorized according to the etiology, clinical stage, and severity of their disease. The severity of pancreatic inflammation was assessed using a scoring system that takes into account the clinical symptoms and treatment options of chronic pancreatitis. Finally, four hypothetical patients were categorized according to the M-ANNHEIM classification system to provide examples of its applicability in clinical practice.

CONCLUSIONS

The M-ANNHEIM multiple risk factor classification system is simple, objective, accurate, and relatively noninvasive, and it incorporates etiology, different stages of the disease, and various degrees of clinical severity. This new classification system will be helpful for investigating the impact and interaction of various risk factors on the course of the disease and will facilitate the comparison and combination of interinstitutional data.

Evaluation of the stimulating effect of a low dose of secretin compared to the standard dose on the exocrine pancreas with MRCP: preliminary results in normal subjects (MRCP quantification of secretin stimulation)

BACKGROUND

Secretin administration during MRCP improves depiction of pancreatic ducts and allows assessment of pancreatic exocrine secretions. However, secretin increases the cost of secretin-enhanced MRCP (S-MRCP). The aim of this study was to quantify using MRCP the stimulating effect of 0.3 CU/kg of secretin and to compare it to the standard dose (1 CU/kg).

METHODS

Ten healthy volunteers underwent four S-MRCP (two for each dose). Pancreatic exocrine secretions were quantified by pancreatic flow output (PFO) and total excreted volume (TEV), derived from a linear regression between MR calculated pancreatic exocrine volumes and time. Two readers analysed individually all sets of images.

RESULTS

A linear increase of pancreatic exocrine volumes was observed after administration of both doses of secretin. Intra-individual and inter-observer differences were not statistically significant (P > 0.05). The mean PFO and TEV, given for reader 1 only, were, respectively, 6.9 +/- 1.5 mL/min and 103 +/- 26 mL for the standard dose and 6.1 +/- 1.2 mL/min and 84 +/- 19 mL for the dose of 0.3 CU/kg. Differences between PFO and TEV obtained with the two doses of secretin were statistically significant for both readers (P < 0.05).

CONCLUSIONS

MRCP is a non-invasive, reproducible tool that allows quantification of pancreatic exocrine secretions during secretin stimulation. PFO and TEV calculated with the low dose were still in the range of previously reported reference values. The administration of 0.3 CU/kg of secretin can reduce significantly the cost of S-MRCP.

Diagnosis of early-stage chronic pancreatitis by secretin-enhanced magnetic resonance cholangiopancreatography

A diagnostic means of detecting chronic pancreatitis at an early stage, when the disease is still reversible, needs to be developed. Magnetic resonance cholangiopancreatography (MRCP) has recently been evolving as an important tool for the evaluation of chronic pancreatitis. In patients with moderate chronic pancreatitis, the pancreatic parenchyma displays an abnormal enhancement pattern on T1-weighted sequences after gadolinium administration. The presence of a signal intensity ratio of <1.7 in the arterial phase and/or delayed peak enhancement after contrast administration has a sensitivity of 92% and a specificity of 75% for the demonstration of early chronic pancreatitis. The secretin-induced pancreatic T2 signal intensity changes are significantly reduced in patients with a mild exocrine pancreatic insufficiency as compared with healthy volunteers. MRCP visualizes fluid in the pancreatic and biliary ducts as high signal intensity on heavily T2-weighted sequences. However, visualization of normal or minimally dilated pancreatic ducts by MRCP is more challenging because of their small size. Secretin administration stimulates fluid and bicarbonate secretion by the exocrine pancreas; consequently, it improves the pancreatic duct and side-branch delineation and allows an evaluation of the exocrine pancreatic function. Side-branch ectasia, mild ductal dilatation with loss of the normal gentle taper, and mural irregularities are the pathognomonic MRCP features of early-stage chronic pancreatitis. Through measurement of the duodenal filling, secretin-MRCP allows quantitative assessment of the exocrine pancreatic function, even in patients with a mild exocrine insufficiency. The morphology of the pancreatic ducts, particularly in the early stages, does not always correlate with the functional status. MRCP permits visualization of the ductal changes and furnishes functional information on the pancreas; this combination may enhance its diagnostic accuracy so that MRCP can become a valuable diagnostic means in early-stage chronic pancreatitis.

Magnetic resonance imaging for diagnosing chronic pancreatitis

Endoscopic retrograde cholangiopancreatography (ERCP) is highly sensitive for detecting chronic pancreatitis, even when mild, but it is invasive. Magnetic resonance cholangiopancreatography (MRCP), a noninvasive modality, well demonstrates dilatation, stricture, and irregularity of the main pancreatic duct as well as filling defects due to pancreatic stones and protein plugs in chronic pancreatitis. MRCP well visualizes the pancreatic ducts distal to the sites of complete obstruction and noncommunicating pseudocysts, in contrast to ERCP. MRCP is sensitive for detecting moderate to severe pancreatitis but not for mild pancreatitis. However, secretin-stimulated MRCP and technological innovations in magnetic resonance may improve diagnostic accuracy. A recently developed technique, secretin-stimulated diffusion-weighted magnetic resonance imaging (DW-MRI), noninvasively and accurately evaluates pancreatic exocrine function. In conclusion, MRCP can most likely replace ERCP for evaluation of moderate to severe chronic pancreatitis. Secretin-stimulated DW-MRI may help to detect mild or early pancreatitis.

Serial contrast-enhanced MRI of the pancreas: correlation with secretin-stimulated endoscopic pancreatic function test

RATIONALE AND OBJECTIVES

The purpose of this study was to determine the relationship between the pancreatic enhancement on serial contrast-enhanced MRI (CEMRI) and pancreatic exocrine function using the secretin-stimulated endoscopic pancreatic function test (ePFT).

MATERIALS AND METHODS

A total of 30 patients with clinical symptoms consistent with chronic pancreatitis underwent CEMRI of the abdomen and ePFT within a 1- to 4-week interval. CEMRI was performed in arterial, early venous, and late venous phases. Secretin ePFT was performed with the measurement of HCO(3) concentration from the duodenal aspirates after secretin stimulation. Contrast enhancement ratio of the arterial phase to early venous phase was measured on CEMRI (SIRa/SIRv). A three-point evaluation system was used for grading the HCO(3) concentration and the enhancement ratio on MRI. For the significance of correlation, kappa statistics was used. Sensitivity and specificity of CEMRI was determined for the diagnosis of early chronic pancreatitis accepting ePFT as a reference.

RESULTS

Twenty patients had identical scores on both secretin ePFT and CEMRI. Ten patients revealed discrepancy in scores. Kappa statistics revealed moderate agreement between MRI and ePFT (kappa = 0.44). Sensitivity and specificity values for the diagnosis of pancreatitis were 82% and 57%, respectively. Positive predictive value was 56%, and negative predictive value was 86%.

CONCLUSION

The results of our data indicate that serial CEMRI is an appropriate imaging technique to rule out early chronic pancreatitis. However, secretin-stimulated imaging or ePFT may still be needed for the definite diagnosis of pancreatic exocrine dysfunction.

Pancreatic adenocarcinoma

Adenocarcinoma is the most common malignant pancreatic tumor, affecting the head of the pancreas in 60-70% of cases. By the time of diagnosis, at least 80% of tumors are unresectable. Helical computed tomography (CT) is very effective in detecting and staging adenocarcinoma, with a sensitivity of up to 90% for detection and an accuracy of 80-90% for staging, but it has limitations in detecting small cancers. Moreover, it is not very accurate for determining nonresectability because small liver metastases, peritoneal carcinomatosis, and subtle signs of vascular infiltration may be missed. Multidetector-row CT (MDCT) has brought substantial improvements with its inherent ability to visualize vascular involvement in three dimensions. MDCT has been found to be at least equivalent to contrast-enhanced magnetic resonance imaging (MRI) for detecting adenocarcinoma. MRI can be used as a problem-solving tool in equivocal CT: MRI may help rule out pitfalls, such as inflammatory pseudotumor, focal lipomatosis, abscess, or cystic tumors. Mangafodipir-enhanced MRI reveals a very high tumor-pancreas contrast, which helps in diagnosing small cancers. Endosonography is, if available, also a very accurate tool for detecting small cancers, with a sensitivity of up to 98%. It is the technique of choice for image-guided biopsy if a histologic diagnosis is required for further therapy.

Pancreatic imaging: current and emerging technologies

This review discusses the current imaging modalities for the diagnosis and staging of solid and cystic pancreatic lesions and for the assessment of acute and chronic pancreatitis, and the future role of emerging technologies in the management of pancreatic diseases. Multidetector row spiral computed tomography is superior to conventional single-detector row spiral computed tomography in the detection and staging of pancreatic adenocarcinoma. Positron emission tomography is a sensitive but relatively nonspecific diagnostic modality. Positron emission tomography-computed tomography fusion may improve the staging accuracy for pancreatic cancer. Echo-enhanced ultrasound may have an emerging role in evaluating pancreatic masses. Endoscopic ultrasound with fine needle aspiration for cytology is the single best method for diagnosis and staging of nonmetastatic pancreatic cancer with a high accuracy for determining tumor resectability. In acute pancreatitis, a modification of the standard computed tomography severity index, which places greater emphasis on extrapancreatic complications, has shown superior correlation with various patient outcome measures. Endoscopic retrograde cholangiopancreatography is still the test of choice for morphological evaluation of chronic pancreatitis, whereas magnetic resonance cholangiopancreatography offers a noninvasive alternative in selected patients. Endoscopic ultrasound can be useful for detecting early chronic pancreatitis. Secretin-stimulated imaging techniques may eventually provide a noninvasive method of reliably assessing pancreatic exocrine function.

Dynamic secretin-enhanced MR cholangiopancreatography

Secretin causes temporary dilatation of pancreatic ducts, principally by increasing pancreatic exocrine secretions, and thus allows better visualization of the ducts at magnetic resonance (MR) cholangiopancreatography. Secretin-enhanced MR cholangiopancreatography is useful for detection and diagnosis of a variety of congenital, inflammatory, and neoplastic conditions of the pancreas. Although MR cholangiopancreatography without secretin is a reliable method for evaluating the pancreatobiliary ductal system, the authors believe that secretin-enhanced MR cholangiopancreatography gives additional valuable functional and anatomic information about the pancreatic duct and pancreatic excretory capacity.

Chronic pancreatitis

PURPOSE OF REVIEW

As in our previous reviews, we endeavor to review important new observations in chronic pancreatitis made in the past year. Topics recently reviewed were truncated to accommodate a surge in publications on clinical aspects of chronic pancreatitis, which contained new observations or insights into new or old concepts.

RECENT FINDINGS

Cystic fibrosis carriers have been found to be at increased risk of pancreatitis. Autoimmune pancreatitis may belong to a multiorgan immunoglobulin G4-related autoimmune disease, and the natural history of chronic pancreatitis differs among the etiologies. Diffusion-weighted magnetic resonance imaging improves upon previous methodologies for diagnosing reduced pancreatic exocrine secretion, and fecal elastase-1 has been found to be a poor test for diagnosing pancreatic malabsorption. Visceral hyperalgesia or heightened central pain perception may contribute to pain in chronic pancreatitis. Instruments are evolving to assess quality of life in chronic pancreatitis, and fibrolytic agents have been found to have therapeutic promise.

SUMMARY

Researchers this past year have further characterized genetic, molecular and clinical aspects of chronic pancreatitis. Advancing the understanding of fibrogenesis, mechanisms of exocrine insufficiency, calcification, and pain and continuing development/modification of diagnostic tests should lead to improved prevention, detection and treatment of the condition. More accurate quantification of outcomes is critical for translating potential therapies from bench to bedside.

Magnetic resonance imaging in the detection of pancreatitis and pancreatic neoplasms

This article presents current magnetic resonance imaging techniques for the diagnosis of acute and chronic pancreatitis and pancreatic neoplasms. It emphasises the need for a comprehensive protocol combining imaging sequences of the pancreatic parenchyma with magnetic resonance angiography and secretin-enhanced magnetic resonance cholangiopancreatography in order to evaluate the full range of pancreatic inflammatory and neoplastic conditions. Imaging characteristics that may indicate a specific diagnosis are discussed.

Chronic pancreatitis: MRCP versus ERCP for quantitative caliber measurement and qualitative evaluation

PURPOSE

To retrospectively compare-in patients with chronic pancreatitis-magnetic resonance cholangiopancreatography (MRCP) and endoscopic retrograde cholangiopancreatography (ERCP) for measurement of main pancreatic duct (MPD) diameter by using area intensity measurement (AIM) at MRCP and full width at half maximum (FWHM) at ERCP and to retrospectively determine the accuracy of MRCP for depiction of pathologic changes by using ERCP as the reference standard.

MATERIALS AND METHODS

The institutional review board approved this study and waived the need to obtain informed consent. Both MRCP and ERCP were performed in 24 patients with chronic pancreatitis (21 men, three women; mean age, 54 years +/- 14 [standard deviation]). The diameter of the MPD was determined by using both methods at the same sites in the head, body, and tail of the pancreas. MRCP and ERCP measurements involved AIM and FWHM techniques, respectively. For qualitative evaluation, visualization of the MPD and pathologic findings was also examined by using both methods. Paired t and Wilcoxon matched-pair signed rank tests were performed for the quantitative and qualitative evaluations, respectively.

RESULTS

The mean diameter of the MPD at ERCP was 1.5 times larger, on average, than that at MRCP; differences were statistically significant for each segment, as well as for the entire duct system. For qualitative evaluation, MRCP tended to be superior to ERCP for delineation of the MPD. Overall sensitivity, specificity, and accuracy values of MRCP for delineating pathologic pancreatic changes were 88% (87 of 99), 98% (44 of 45), and 91% (131 of 144), respectively.

CONCLUSION

Use of ERCP tends to result in overestimation of the caliber of the MPD. MRCP can enable accurate evaluation of the condition of the pancreatic duct and its changes in patients with chronic pancreatitis.

Exocrine pancreatic function: evaluation with MR imaging before and after secretin stimulation

Secretin-stimulated magnetic resonance cholangiopancreatography (SS-MRCP) enhances standard pancreatic imaging in chronic pancreatitis. Diffusion-weighted MRI added to SS-MRCP allows a qualitative and potentially quantitative estimate of pancreatic exocrine secretion, providing an alternative to standard "tube" tests.