Sinus may refer to: In anatomy, where a sinus is a sac or cavity in any organ or tissue: Sinus (anatomy), description of the general term; Anal sinuses, the furrows which separate ...
There are two Pericardial sinuses: transverse and oblique. The cul-de-sac enclosed between the limbs of the inverted U of the venous mesocardium lies behind the left atrium and is ...