Medically termed sinusitis, a sinus infection occurs when the cavities around your nose become swollen and inflamed. Sinusitis is most often caused by a virus and often lasts long after the other upper respiratory symptoms are gone. Rarely, fungus or bacteria may cause a sinus infection.
The inner coat is double with one layer closely adherent to the heart while the other lines the inner surface of the outer coat with the intervening space being filled with fluid. This small amount of fluid, the pericardial fluid, acts as a lubricant to allow normal heart movement within the chest.
Presence of echo-. free space between the two layers of pericardium throughout. the cardiac cycle confirms the diagnosis. 2 Normally also, there. is small amount of fluid (5-15 ml) in the pericardial sac. However, in normal persons, a clear space between the two. layers of pericardium can be seen only during systole.