Portal Annular Pancreas: An Underrecognized Variant, Prevalence, and Clinical Relevance

Abstract

Background : The portal annular pancreas is a rare morphological variant where the pancreatic parenchyma encircles the portal vein or the superior mesenteric vein and fuses with the body of the pancreas. It may be mistaken for a pancreatic head mass and has grave implications for patients planned for pancreatic surgeries. Aim : This study aimed to determine the prevalence of portal annular pancreas in a cohort of patients attending a tertiary care referral centre in South India and to assess how frequently this was identified and reported in a routine CT scan report. Methods : A retrospective review of consecutive contrast-enhanced multi-detector computed tomography (MDCT) scans of the abdomen during the study period was used to assess for the presence of portal annular pancreas. It was classified into suprasplenic, infrasplenic, and mixed variants based on its relation to the splenoportal confluence. In addition, the radiology reports were reviewed with regard to mention of this variant. Results : The prevalence of portal annular pancreas in our study population was 25 out of 1000 patients (2.5%). There was an increased frequency of this anomaly in females; male: female ratio was 1:2.1. The most common morphological type was suprasplenic fusion. The portal annular pancreas was mentioned in only 1 out of 25 (4%) of the radiology reports. Conclusion : The prevalence of portal annular pancreas was 2.5% with a female preponderance in our series. This entity can be easily overlooked, and increased awareness would improve identification, thereby mitigating complications associated with pancreatic surgery.