Differences on DWI may help to differentiate PC, mass-forming FP, and normal pancreas from each other.

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Purpose: To review magnetic resonance imaging (MRI) and secretin stimulated magnetic resonance cholangiopancreatography (S-MRCP) findings of patients with suspected chronic pancreatitis and compare them with endoscopic pancreatic function testing (ePFT). Materials and Methods:MRI and S-MRCP findings of 36 patients with clinically suspected chronic pancreatitis were reviewed. Baseline ductal changes, duodenal filling grades, and pancreatic duct caliber change (PDC) on S-MRCP, mean values of pancreatic anteroposterior (AP) diameter, signal intensity ratio (SIR) between pancreas and the spleen on T1-weighted fat saturated images, and arterial to venous (A/V) enhancement ratios were compared between groups of normal and abnormal pancreatic exocrine function determined by ePFT.Results: All patients (n ¼ 24) with normal ePFT (HCO 3 >80 mEq/L) had grade 3 normal duodenal filling. Patients with abnormal ePFT (HCO 3 <80 mEq/L) (n ¼ 12) had grade 1 (n ¼ 1) and grade 2 (n ¼ 11) diminished duodenal filling (P < 0.0001). PDC was 1.51 in the normal ePFT group versus 1.27 in the abnormal ePFT group (P ¼ 0.01). No significant differences were found in terms of mean pancreatic AP diameter (21.8 vs. 19.8 cm), SIR (1.59 vs. 1.44), and A/V (1.08 vs. 1.01) between groups of normal/abnormal pancreatic exocrine function. Conclusion:Despite discrepancies between pancreatic exocrine function and the findings on standard MRI/ MRCP, the S-MRCP findings are comparable to ePFT in the evaluation of chronic pancreatitis. CURRENTLY, the most sensitive diagnostic tool to detect chronic pancreatitis at its earliest stage is hormonal pancreatic function testing. Secretin stimulated endoscopic pancreatic function testing (ePFT) is considered one of the most sensitive clinical pancreatic exocrine function testing methods (1-3). Secretin stimulated magnetic resonance cholangiopancreatography (S-MRCP) can estimate pancreatic exocrine function, and at the same time an increased number of side branch ectasia and or decreased pancreatic duct compliance after secretin stimulation can be demonstrated as early imaging findings of chronic pancreatitis (4-7). In addition, there have been studies that compared pancreatic exocrine function and pancreatic parenchymal and ductal findings on magnetic resonance imaging (MRI), MRCP, ERCP, and endoscopic ultrasound (EUS). Discrepancies have been reported over the years between each imaging modality and exocrine function test (4,7-11).The purpose of this study was 2-fold; first, we compared ePFT with S-MRCP for the assessment of pancreatic exocrine function. Second, we reviewed if pancreatic exocrine function correlates with the parenchymal imaging findings on MRI and ductal changes on MRCP before and after secretin stimulation.

Diffusion-weighted imaging (DWI) assesses the random motion of the water protons. The technique is more frequently used in body imaging, and recent investigations showed its use in pancreatic imaging. Diffusion-weighted imaging can be helpful as a complementary imaging method in the differentiation between mass-forming focal pancreatitis and pancreatic adenocarcinoma. The apparent diffusion coefficient (ADC) values derived from DWI can distinguish between simple pancreatic cyst, inflammatory cysts, and cystic neoplasms of the pancreas. Presence of parenchymal fibrosis in chronic pancreatitis causes diffusion restriction and results in lower ADC values on baseline DWI. The ADC values reveal either delayed peak after secretin stimulation or lower peak values in patients with early chronic pancreatitis, which may be helpful to depict chronic pancreatitis in its earliest stage. In this paper, we reviewed the technical aspects of DWI and its use in pancreatic imaging.

Purpose: To review pancreatic MRI findings and their relationship with estimated pancreatic exocrine function on secretin-stimulated MR cholangiopancreatography (S-MRCP) in patients with clinically suspected chronic pancreatitis and normal baseline MRCP findings. Materials and Methods:MRI findings of 26 patients with normal pancreatic duct diameter and without side branch ectasia on MRCP were evaluated. A single radiologist assessed pancreatic size, pancreatic signal intensity ratio (SIR), and arterial enhancement ratio (A/V) at head, body, and tail of the pancreas on T 1 -weighted fat-suppressed and serial contrast-enhanced images at a single session. Combined findings were graded with a composite score. Serial S-MRCP was performed at the same session with standard MRI. Correlation and differences between MRI findings and associated grade of duodenal filling (DF) or the degree of pancreatic duct caliber change (PDC) were analyzed.Results: Seven patients revealed normal and 19 patients abnormal MRI findings. Significant correlation was present between the degree of DF and mean values of pancreatic size (r ϭ 0.748), SIR (r ϭ 0.610), A/V (r ϭ 0.466), composite score (r ϭ 0.833), and PDC (r ϭ 0.554) separately. PDC correlated with SIR (r ϭ 0.413) and composite score (r ϭ 0.452), but not with A/V or pancreatic size. Significant differences were present between normal and abnormal DF grades in terms of mean values of associated findings of size (P ϭ 0.001), SIR (P ϭ 0.008), A/V (P ϭ 0.019), and PDC (P ϭ 0.001). Conclusion:Patients with clinically suspected chronic pancreatitis and normal MRCP findings may have a spectrum of MRI findings that correlate with the estimated pancreatic exocrine insufficiency on S-MRCP with the increasing number of combined findings. PATIENTS WITH CLINICALLY suspected chronic pancreatitis undergo imaging and/or pancreatic function testing to rule out early chronic pancreatitis. Pancreatic exocrine insufficiency determined by secretin-stimulated pancreatic function testing is a very sensitive marker for the diagnosis of early chronic pancreatitis (1). Abnormal results in pancreatic function testing precede imaging findings in cases with mild early chronic pancreatitis (2). The Cambridge classification system has been used for the diagnosis and staging of chronic pancreatitis on imaging studies. Patients with normal pancreatic duct on endoscopic retrograde cholangiopancreatography (ERCP) are considered normal according to that classification (3). ERCP is the most sensitive imaging method for the evaluation of pancreatic duct and its side branches. Despite of its high sensitivity, ERCP is less frequently used for screening patients with clinical symptoms of chronic pancreatitis because the test is invasive and costly. Besides, normal ERCP cannot exclude early changes of chronic pancreatitis (1,4). MR cholangiopancreatography (MRCP) as a noninvasive test has been increasingly used to rule out chronic pancreatitis and replaced the role of ERCP for screening. According to the most recent studies...

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Magnetic resonance imaging (MRI) is a valuable tool in the assessment of the full spectrum of pancreatic disease. A standard MR protocol including noncontrast T1-weighted fat-suppressed and dynamic gadolinium-enhanced gradient-echo imagings is sensitive for the evaluation of pancreatic cancer. Optimal use of MRI in the investigation of pancreatic cancer occurs in the following circumstances: (1) detection of small non-contour-deforming tumors, (2) evaluation of local extension and vascular encasement, (3) determination of the presence of lymph node and peritoneal metastases, and (4) determination and characterization of associated liver lesions and liver metastases. The objective of this study was to describe the attribute of MRI for evaluating pancreatic cancer.

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