Figure 18c. Pericardial cyst in an asymptomatic 56-year-old man. (a) Axial ECG-gated T1-weighted SE image shows a mass (*) with intermediate signal intensity, adjacent to the main pulmonary artery. (b) Axial gadolinium-enhanced T1-weighted image obtained at the same level as a shows no enhancement of the mass (*) after administration of gadolinium. (c) Axial T2-weighted fast SE image shows a mass (*) with homogeneous high signal intensity. PA = pulmonary artery.