Imaging characteristics of autoimmune pancreatitis / 中华放射学杂志

ABSTRACT

Objective To investigate the imaging characteristics of autoimmune pancreatitis (AIP).Methods MR imaging was performed in 12 patients with AIP proved histopathologically or clinically,of them CT was scanned in 10 patients and endoscopic retrograde cholangiopancreatography (ERCP)in 3.All imaging data were reviewed retrospectively.Results All 12 patients had enlargement of the pancreas either diffusely(n=9)or focally(n=3).The swollen pancreas was hypointense on T_1-weighted images and mildly hyperintense on T_2-weighted images.It also demonstrated decreased enhancement on artery phase of dynamic imaging and moderate enhancement on delayed phase images. Capsule-like enhanced rim was found around the swollen pancreas in 11 patients.Stricture of the distal common bile duct was found in 9 patients,and ERCP showed diffuse and irregular narrowing of the main pancreatic duct in 3 cases.At follow-up,pancreatic abnormalities and common bile duct stricture resolved after steroid therapy in 7 patients.Conclusion AIP showed some characteristic imaging findings,and imaging examinations will play an important role in the diagnosis of AIP.