Sphenoidal sinus
Sinus sphenoideus
- Latin synonym: Sinus paranasalis sphenoideus
- Synonym: Sphenoidal paranasal sinus
Definition
The Sphenoidal Sinuses (sinus sphenoidales) contained within the body of the sphenoid vary in size and shape; owing to the lateral displacement of the intervening septum they are rarely symmetrical.
The following are their average measurements: vertical height, 2.2 cm.; transverse breadth, 2 cm.; antero-posterior depth, 2.2 cm. When exceptionally large they may extend into the roots of the pterygoid processes or great wings, and may invade the basilar part of the occipital bone.
Each sinus communicates with the sphenoethmoidal recess by means of an aperture in the upper part of its anterior wall. They are present as minute cavities at birth, but their main development takes place after puberty.
This definition incorporates text from a public domain edition of Gray's Anatomy (20th U.S. edition of Gray's Anatomy of the Human Body, published in 1918 – from http://www.bartleby.com/107/).
