The Choanae are the posterior nasal aperture, separated by the vomer.
It is the opening between the nasal cavity and the nasopharynx.
It is therefore not a structure but a space bounded as follows:
This definition incorporates text from the wikipedia website - Wikipedia: The free encyclopedia. (2004, July 22). FL: Wikimedia Foundation, Inc. Retrieved August 10, 2004, from http://www.wikipedia.org
- anteriorly and inferiorly by the horizontal plate of palatine bone,
- superiorly and posteriorly by the sphenoid bone
- laterally by the medial pterygoid plates.