APPLIED RADIOLOGICAL ANATOMY

Detailed explanation-1: -The pericardium is a double-layer-fibrous outermost layer and serous innermost layer-sac of fibroelastic/fibroserous tissue encasing the heart, anchoring it to the mediastinum (a passageway for many structures that pass through the thorax), and forming a cavity filled with a serous fluid.

Detailed explanation-2: -The pericardium, also called pericardial sac, is a double-walled sac containing the heart and the roots of the great vessels. It has two layers, an outer layer made of strong connective tissue (fibrous pericardium), and an inner layer made of serous membrane (serous pericardium).