Circumportal pancreas: prevalence, subtypes and vascular variations of 55 patients.

PURPOSE

To determine the frequency of circumportal pancreas (CP), and accompanying ductal and vascular anatomy variations.

METHODS

Thin-section multidetector computed tomography of 6813 consecutive patients was retrospectively reviewed. Two radiologists evaluated CP presence with consensus. Concomitant pancreatic ductal and vascular variations were recorded. The course of the pancreatic duct was classified according to the portal vein as anteportal and retroportal, and pancreas fusion level classified according to splenic vein as suprasplenic, infrasplenic and mixed type.

RESULTS

A total of 55 (0.8%) CP cases were detected. Six suprasplenic subtype cases were excluded from the classification, because the pancreatic ducts were not clearly distinguishable. Suprasplenic anteportal (45/49, 92%), infrasplenic anteportal (2/49, 4%), suprasplenic retroportal (1/49, 2%), and mixed anteportal subtypes (1/49, 2%) were detected. There were vascular variations in 16 cases (29%). 13/16 (81%) of vascular variations were detected on suprasplenic anteportal subtype. Most of them were replaced right hepatic artery from the superior mesenteric artery (n: 6).

CONCLUSIONS

CP is a rare but important pancreatic fusion anomaly. Suprasplenic anteportal CP is the most common subtype and other subtypes are very rare. Replaced right hepatic artery from the superior mesenteric artery is the most frequent vascular variation associated with CP. Identifying the CP and defining the pancreatic duct and vascular variations are important to prevent possible complications in patients undergoing pancreatic surgery.