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Vein channel in the skull
Blood vessel
Sigmoid Sinus
Dural veins. ("Pars sigmoid" labeled at lower right.)
The sigmoid sinuses (sigma- or s-shaped hollow curve), also known as the pars sigmoid, are paired dural venous sinuses within the skull that receive blood from posterior transverse sinuses.
The sigmoid sinus receives blood from the transverse sinuses, which receive blood from the posterior aspect of the skull. Along its course, the sigmoid sinus also receives blood from the cerebral veins, cerebellar veins, diploic veins, and emissary veins.
References
^ Drake, Richard L.; Vogl, Wayne; Tibbitts, Adam W.M. Mitchell; illustrations by Richard; Richardson, Paul (2005). Gray's anatomy for students (Pbk. ed.). Philadelphia: Elsevier/Churchill Livingstone. ISBN978-0-443-06612-2.