Type 1 Autoimmune Pancreatitis Can Transform into Chronic Pancreatitis: A Long-Term Follow-Up Study of 73 Japanese Patients

Figure 4

Sequential progression mechanism of AIP to confirmed chronic pancreatitis. (a) Narrowing of both Wirsung’s and Santorini’s ducts (arrows) by pancreatic head swelling causes pancreatic juice stasis in the upstream pancreatic duct. (b) Pancreatic juice stasis results in increased intrapancreatic duct pressure, that is, resistance to typical AIP-specific MPD narrowing in the pancreatic body region, leading to MPD nonnarrowing in this region (arrowheads). (c) These events finally result in severe calcification.