sinus - Anatomy

In anatomy, a space within the head or elsewhere in the body. The air-filled paranasal sinuses all communicate with the nasal cavity, at the front of the face, and are lined with respiratory epithelium. Their purpose is to lighten the skull and also act as resonance chambers in the production of sounds. (A change in the quality of the voice during a cold results from these sinuses becoming infected, and filling with fluid, thus affecting their resonating properties.) The blood-filled intracranial sinuses are generally found between the layers of the outer membrane which surrounds the brain (the dura mater), and drain venous blood from the brain to the internal jugular vein. The term sinus is also used in pathology to refer to an abnormal, blind-ended opening on an epithelial surface.

The term sinus (Latin for "bay", "pocket", "curve" or "bosom") is used in various contexts.

Anatomy

A sinus is a sack or cavity in any organ or tissue, or an abnormal cavity or passage caused by the destruction of tissue. In common usage, "sinus" usually refers to the paranasal sinuses, which are air cavities in the cranial bones, especially those near the nose and connecting to it.

The term "sinus" is also used for the following structures:

The dural venous sinuses, venous channels found between layers of dura mater in the brain. Various structures of the heart: The sinus node is a structure in the superior part of the right atrium of the heart, producing the electrical impulse for the heart's contraction. "Sinus" is also sometimes used short for sinus rhythm. The coronary sinus is a vein collecting blood from the heart and draining into the right atrium. The sinus venosus is a cavity in the heart of embryos. The sinus venarum is a part of the wall of the right atrium in adults; it develops from the sinus venosus. see Sinus and Paludes. Sine or sinus hyperbolicus is a hyperbolic function

This disambiguation page lists articles associated with the same title.