Cuneiform sinus

The sphenoid sinus (sinus sphenoidalis) is located in the body of the sphenoid bone. The lower wall of the sinus participates in the formation of the wall of the nasal cavity. The cavernous sinus is adjacent to the upper part of the lateral wall. The sphenoid sinus is usually divided into two asymmetric parts by the sagittal septum. Sometimes the septum is absent. The sphenoid sinus communicates with the superior nasal passage.

The air cavities communicating with the nasal cavity are the anterior, middle and posterior cells of the ethmoid bone.