arachnoid villa

anatomy

Also known as: arachnoid granulations

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Last updated

June 18, 2026

Quick Summary

Arachnoid villi are fingerlike projections of the arachnoid mater, one of the three protective membranes surrounding the brain and spinal cord. These villi extend into the dural sinuses, which are venous channels within the dura mater.12

The primary function of arachnoid villi is to facilitate the reabsorption of cerebrospinal fluid (CSF) from the subarachnoid space into the bloodstream via the dural sinuses. This process is crucial for maintaining the proper volume and pressure of CSF within the central nervous system.12

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meninges
Dura mater
…of the arachnoid, known as arachnoid villi or arachnoid granulations, are involved in the passage of CSF from the subarachnoid space to the dural sinuses. Spinal anesthetics are often introduced into the subarachnoid space.
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…of the arachnoid, known as arachnoid villi or arachnoid granulations, are involved in the passage of CSF from the subarachnoid space to the dural sinuses. Spinal anesthetics are often introduced into the subarachnoid space.
Read More