Suspected chronic pancreatitis with normal MRCP: Findings on MRI in correlation with secretin MRCP

Abstract

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...

Pleuropancreatic Fistulae: Specialist Center Management

“…The addition of secretin stimulation increases pancreatic exocrine secretion, and therefore enhances the quality of duct imaging. 13 Often, the duct injury is identified with MRCP and the remainder of the duct can also be evaluated for associated strictures or stones, guiding definitive management. Endoscopic retrograde pancreatography is the most sensitive and specific modality to identify pancreatic duct anatomy and the site of disruption.…”

Evaluation of Qualitative Magnetic Resonance Imaging Features for Diagnosis of Chronic Pancreatitis

“…The qualitative MRI/MRCP features representing pancreatic parenchymal and before and after secretin ductal changes in CP [19][20][21] have been listed in Table 1. These features were identified by consensus by 2 abdominal radiologists (K.M., N.S.)…”

Tests of pancreatic exocrine function – Clinical significance in pancreatic and non-pancreatic disorders

“…However as a stand alone test in early chronic pancreatitis the lack of sensitivity (50-93%) and the lack of specificity (62-93%) limit its diagnostic value [39]. Recently with the aim to combine morphology and pancreatic function but avoid invasive procedures such as ERCP the use of secretin stimulated MRI was evaluated [40]. Duodenal filling as a result of secretin stimulation can be compared to duct changes on MRCP [41], but the number of patients with suspected chronic pancreatitis recruited to trials comparing MRI to secretin-stimulated pancreatic function is still too low to allow for final evaluation of this method or to give reliable values for sensitivity and specificity over the whole spectrum of pancreatic impairment.…”