*3.1.2 Anatomical anomalies*

Pancreas divisum is the most frequent anatomical variant and has an incidence near to 12% in general population. As a result of this incomplete fusion of the ventral and dorsal ducts pancreatic juices cause ductal hypertension. Patients may experience recurrent pain after food intake, an alteration in serum content of pancreatic enzymes, or acute recurrent pancreatitis. Annular pancreas is another anatomical variant that may be related with duodenal or biliary obstructive symptoms. Ductal abnormalities such as a common pancreatico-biliary channel may determine a bile or pancreatic juices reflux and can be diagnosed with ERCP. Sphincter of Oddi dysfunction (SOD) is another factor predisposing to ARP and is probably the most common cause of the idiopathic form. This dysfunction includes two clinical forms: SO increased basal pressure related to a structural fibrotic alteration of the sphincter and SO dyskinesia, caused by sphincter hypertone [19].
