Sigmoid Sinus viewed from Above

Description

Superior views across the cranial base bring the dural venous sinuses into clear relief, with the paired sigmoid sinuses highlighted in blue as they curve inferolaterally along the posterolateral margins of the posterior cranial fossa. Each sigmoid sinus continues from the transverse sinus near the occipital bone and temporal bone junction, then sweeps anteriorly and inferiorly toward the jugular foramen to become the internal jugular vein. Medially, the foramen magnum sits as the dominant midline landmark, while laterally the mastoid part of the temporal bone frames the S shaped groove that houses the sinus. Bone is sectioned to expose internal contours. This angle matters when you need to teach or plan around venous outflow at the skull base. The sigmoid sinus lies immediately deep to the mastoid air cells, which is why mastoidectomy and posterior fossa approaches carry a real risk of venous sinus injury and brisk hemorrhage if the bony plate over the sinus is thin or dehiscent. Thrombosis at the transverse sigmoid junction also produces characteristic imaging patterns, and the relationship to the jugular foramen helps anchor discussions of otogenic intracranial complications and dural sinus thrombosis pathways. Use this artwork in neuroanatomy and head and neck teaching sessions to connect osteologic landmarks (mastoid, occipital condyles, jugular foramen, foramen magnum) with the dural venous sinus system, and in surgical atlases or CME material covering mastoid surgery, retrosigmoid craniotomy corridors, and venous sinus complications. Anatomical accuracy verified by SciePro's Medical Advisory Board.