Petrosquamous sinus
Sinus petrosquamosus
Definition
The petrosquamous sinus, is a fetal vein that generally disappears by birth and, when present, runs backward along the junction of the squama and petrous portion of the temporal, and opens into the transverse sinus.
References
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/).