Anatomy, Head and Neck, Nose Sinuses

Excerpt

A sinus is defined as:

1. A channel that is not a blood or lymphatic vessel that allows for the passage of blood or lymph, such as found in the placenta, sinuses, or the cerebral meninges

2. A cavity or hollow space in bone or other tissue

3. A dilation in a blood vessel

4. A fistula or tract that transforms into a cavity

There are many types of sinuses, such as the paranasal sinuses of the skull or the dural sinuses of the cerebral meninges. The pericardial sinuses are formed during embryological development as a consequence of heart formation and act as important structures for cardiothoracic surgeons to place ligature for vessel occlusion during surgery. This article will focus on the anatomical sinuses of the nasal and paranasal areas.

Sinuses are located throughout the body and perform varying functions. Sinuses are typically associated with the cavities within the skull. The word “sinus” is most commonly understood to be the paranasal sinuses that are located near the nose and connect to the nasal cavity. There are four paranasal sinuses, each corresponding with the respective bone from which it takes its name: maxillary, ethmoid, sphenoid, and frontal. Sinuses also exist in the dura of the brain, which includes the superior sagittal, straight, and the sigmoid, among others. These dural venous sinuses function as the brain’s venous system. Other sinuses are in the kidney, heart, and lymphatic system.