Increased fat in pancreas not associated with risk of pancreatitis post-endoscopic retrograde cholangiopancreatography

BACKGROUND A preliminary study has shown increased pancreatic fat in patients with idiopathic pancreatitis and sphincter of Oddi dysfunction. In this study, we aimed to determine if an increased quantity of pancreatic fat is an independent risk factor for pancreatitis post-endoscopic retrograde cholangiopancreatography (ERCP). METHODS In this case control study, we retrospectively reviewed a local radiological and ERCP database to identify patients who had had abdominal magnetic resonance imaging (MRI) followed by ERCP no more than 60 days later between September 2003 and January 2011. Percentage of fat was determined by recording signal intensity in the in-phase (Sin) and out-of-phase (Sout) T1-weighted gradient sequences, and calculation of the fat fraction as (Sin - Sout)/(Sin) × 2 by an abdominal radiologist blinded to clinical history. Controls matched for age, gender, and other pancreatobiliary disease were selected from a group with no post-ERCP pancreatitis (before fat content of the pancreas was analyzed). RESULTS Forty-seven patients were enrolled. Compared with controls, subjects with post-ERCP pancreatitis were similar in terms of age (41.4 years versus 41.1 years), gender (21.2% versus 20.2% males), pancreatobiliary disease characteristics, and most ERCP techniques. Measurements of pancreatic head, body, and tail fat and body mass index were similar in patients and controls. CONCLUSION Increased pancreatic fat on MRI criteria is not an independent predictor of post-ERCP pancreatitis.