Computed Tomography and Magnetic Resonance Imaging Features of Posterior Mediastinal Ganglioneuroma

Abstract

To evaluate computed tomography (CT) and magnetic resonance (MR) imaging findings of posterior mediastinal ganglioneuromas. Of 14 pathologically confirmed ganglioneuromas seen in 13 patients, 13 were evaluated by CT images with and without contrast, 11 were evaluated with conventional spin-echo MR images, and 5 were evaluated with contrast-enhanced MR examination. The morphologic features, attenuation, signal intensity, and dynamic enhancement pattern of the neoplasms were evaluated. All lesions were identified as a well-demarcated oval and/or lobular mass. CT attenuation was predominantly low. Calcification on CT scan was seen in 38% of the cases. Whorled appearance (42%) and tailed-shaped edge (14%) were seen on both CT and MR images. Fat components (29%) observed histologically were also detected in tumors on CT and MR images. MR signal intensity in the lesions was mainly low on T1-weighted images and high on T2-weighted images. Contrast enhancement of the tumors was poor in 46% on dynamic CT study. In all 5 contrast-enhanced MR examinations, all lesions were enhanced. The characteristic findings of posterior mediastinal ganglioneuromas are a craniocaudally oblong-shaped mass, calcification, whorled appearance, tail-like extension, and fat component. Poor enhancement on dynamic CT studies is commonly observed.