Arachnoid Mater in a Section of the Skull, Superior View

Description

Cranial cavity is opened in section to expose the arachnoid mater draped over the cerebral convexities, lying deep to the dura mater and superficial to the pia mater that closely invests the gyri and sulci. Superiorly, the dura forms the inner table lining and may be reflected toward the falx cerebri along the midline, while the arachnoid bridges across sulci to create the subarachnoid space. Within that space, cerebrospinal fluid separates arachnoid from pia, and superficial cerebral veins course toward the dural venous sinuses as bridging veins. Midline relationships are clear. A superior meningeal view matters when teaching or planning around the subarachnoid space and its communications, because hemorrhage and infection follow these planes rather than parenchymal boundaries. Subarachnoid hemorrhage tracks around cortical sulci and cisterns, while a subdural hematoma accumulates between dura and arachnoid after tearing of bridging veins, a distinction that drives CT interpretation and operative drainage strategy. The same anatomy frames lumbar puncture teaching by contrast: CSF is sampled from the subarachnoid space, not the potential subdural space. Use this illustration to anchor neuroanatomy and head and neck anatomy coursework on the meninges, CSF spaces, and venous drainage, or as a figure for neurosurgery and neuroradiology texts discussing subdural versus subarachnoid collections. It also fits patient-facing or trainee-oriented materials on meningeal layers encountered during craniotomy and dural opening. Anatomical accuracy verified by SciePro's Medical Advisory Board.