The body is the centrally positioned cuboid-shaped part that is located in the midline. It is a hollow structure, as it contains two large paranasal sinuses called the sphenoid sinuses (Read more!). They are the most posteriorly located paranasal sinuses, and both are divided into two parts by a bony septum. Usually, the septum is not located in the midline, but it is bent to one or the other side.