MRI AND CT IN THE DIAGNOSIS AND FOLLOW-UP OF IDIOPATHIC (RETROPERITONEAL) FIBROSIS

Six cases of idiopathic fibrosis are presented to demonstrate the diff erent manifestations of the disease and the efficiency of CT and MRI. In addition to the most common form, retroperitoneal fibrosis (Ormond' s disease), fibrosis was seen in the mediastinum and pelvis. The infla mmatory aortic aneurysm is a special variant. MRI was superior to CT i n many diagnostic requirements. The extent of fibrosis was demonstrate d more sensitively and MRI showed sclerosis in regions that appeared n ormal on CT. Occlusion of large vessels and collateral circulation wer e better depicted on MRI. The superior tissue contrast of MRI permitte d differentiation of several stages of inflammation, which is of major significance for treatment and follow-up.