Cut Section of the Skull Revealing the Tentorium

Description

Sectioned calvaria and cranial cavity expose the tentorium cerebelli as a transverse dural septum separating the supratentorial cerebral hemispheres from the infratentorial posterior cranial fossa. The tentorial notch (incisura tentorii) is visible as an anterior medial gap, positioned around the midbrain and continuous superiorly with the falx cerebri and laterally with dural reflections along the petrous part of the temporal bone. Posteriorly, the tentorium slopes toward the internal occipital region where it attaches near the grooves for the transverse sinuses. Clear relationships. Recognition of the tentorial margin matters because it is the fixed edge against which the medial temporal lobe can herniate during raised intracranial pressure, producing uncal herniation with ipsilateral oculomotor nerve compression and posterior cerebral artery compromise. This cut section also supports teaching of transtentorial pressure gradients, showing why infratentorial masses threaten the brainstem early, and why imaging reports localize lesions as supratentorial or posterior fossa. Neurosurgical corridors, from suboccipital craniotomy to the supracerebellar infratentorial approach, are planned with these dural attachments in mind. Use this artwork in gross anatomy and neuroanatomy courses when introducing meningeal reflections, dural venous sinus topography, and compartmentalization of intracranial pathology. It also fits neurology and neurosurgery texts discussing herniation syndromes, as well as radiology teaching files that correlate CT or MRI with the tentorial incisura and posterior fossa anatomy. Anatomical accuracy verified by SciePro's Medical Advisory Board.