Figure 14b. Effusive constrictive pericarditis secondary to viral infection in a 65-year-old man with symptoms of heart failure. (a) Axial ECG-gated T1-weighted SE image shows a crescent-shaped area of intermediate signal intensity (arrows) surrounding the ventricles, which indicates either pericardial thickening or pericardial effusion. (b) Axial gadolinium-enhanced fat-saturated T1-weighted SE image shows marked thickening and enhancement in the pericardium (arrows), findings consistent with inflammation. A moderate-sized pericardial effusion is also depicted.