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.