Abstract
Purpose
Understanding the embryogenesis of the pancreas is crucial for identifying pancreatic variants and anomalies. This study aims to describe the imaging features of annular pancreas, focusing on whether the ductal configurations support the embryological theories proposed by Lecco and Baldwin.
Methods
We retrospectively studied 17 patients diagnosed with annular pancreas via computed tomography (CT) and/or magnetic resonance imaging (MRI) at our institution between 2007 and 2019. Two radiologists classified the ductal configurations by consensus using Lin’s classification: Type I (divisional), Type II (branch), and Type III (main duct). Clinical presentations and the impact of annular pancreas diagnosis were recorded.
Results
Among the 17 patients, 5 were Type I, 11 were Type II, and 1 was Type III. The alignment of all patients with Lin’s classification types supports Baldwin's dual-bud theory. None of the patients exhibited symptoms of upper gastrointestinal tract obstruction directly attributable to annular pancreas. Pancreatic diseases were diagnosed in 6 patients, with the annular pancreas having a clinically significant impact in 3 patients for diagnosis (n = 2) or treatment (n = 1).
Conclusion
Our findings in 17 patients suggest that Baldwin’s dual-ventral-bud theory may explain most cases of annular pancreas.