The Secretory Flow of Pancreatic Juice in the Main Pancreatic Duct: Visualization by Means of MRCP with Spatially Selective Inversion-Recovery Pulse

Abstract

To assess the feasibility of visualizing noninvasively the physiologic flow of pancreatic juice by using serial magnetic resonance cholangiopancreatography (MRCP) with a spatially selective inversion-recovery (IR) pulse in volunteers and patients with pancreatic disease. The study was approved by the institutional review board, and informed consent was obtained. Twelve healthy volunteers and three patients with acute pancreatitis were included. MRCP with a spatially selective IR pulse was repeatedly performed every 15 seconds during a total of 10 minutes (total of 40 images). MRCP images were evaluated for the presence, frequency, and magnitude of pancreatic juice inflow within the tagged area. The two groups were compared by using the Mann-Whitney test. Pancreatic juice inflow was observed in all healthy volunteers and in two of three patients with acute pancreatitis. The pancreatic fluid inflow was observed 25-37 times (median, 32 times; mean, 31.4 times; range, 25-37 times) in a series of 40 images in 12 healthy volunteers, while it was seen 0-11 times (median, 2 times; mean, 4.3 times; range, 0-11 times) in a series of 40 images in the three patients with acute pancreatitis (P = .009). No regularity in the timing of the pancreatic fluid inflow was noted. The distance that the pancreatic fluid moved in the pancreatic duct within the tagged area was significantly longer in healthy volunteers (median grade, 2.46; mean grade, 2.41; range, 1.6-3.3) than in patients with acute pancreatitis (median grade, 0.05; mean grade, 0.13; range, 0-0.35) (P = .009). The physiologic flow of the pancreatic juice can be visualized noninvasively with serial MRCP by using a spatially selective IR pulse.