Abdominal tuberculous lymphadenopathy: MR imaging findings

Background. The purpose of this study was to evaluate the utility of magnet ic resonance imaging (MRI) as a diagnostic tool in abdominal tuberculous ly mpbadenopathy. Methods: MRI studies of 11 patients with histologically proven abdominal tu berculous lymphadenopathy were reviewed with regard to anatomic distributio n, size, shape, degree, and pattern of enhancement and relation of the lesi ons to adjacent structures. Results: The most common site of involvement was the periportal area (n = 6 ), followed by the peripancreatic (n = 5), mesenteric (n = 1), and paraaort ic (n = 1) areas. Eight patients were readily diagnosed as having tuberculo us lymphadenopathy on abdominal computed tomography. Three patients had a h eterogeneously enhancing masslike lesion adjacent to the pancreas and were initially diagnosed as having cystic tumor of the pancreas. On MRI, 11 lesi ons showed T1 iso- or hypointensity and central T2 hyperintensity. Two lesi ons showed T1 iso- or hypointensity and central T2 hypointensity. The lesio ns with different T2 signal intensities showed different patterns of enhanc ement on contrast-enhanced dynamic studies. The relations between the enlar ged lymph nodes and adjacent bile ducts or vascular structrues were well de picted on MRI. Conclusion: MRI was useful in differentiating enlarged lymph nodes abutting the pancreas initially diagnosed as cystic neoplasms on abdominal computed tomography.