Arachnoid granulation

From WikiMD's Food, Medicine & Wellness Encyclopedia

Arachnoid granulations (also known as Pacchionian granulations) are small protrusions of the arachnoid mater (the middle layer of the meninges) into the outer membrane of the dura mater. They protrude into the venous sinuses of the brain, and allow cerebrospinal fluid (CSF) to exit the subarachnoid space and enter the blood stream.

Structure[edit | edit source]

Arachnoid granulations are composed of clusters of arachnoid cells. They are located in the dura mater, the outermost of the three layers of the meninges. The granulations are most commonly found in the superior sagittal sinus, one of the venous sinuses of the brain, but can also be found in other dural sinuses.

Function[edit | edit source]

The primary function of arachnoid granulations is the reabsorption of cerebrospinal fluid (CSF) from the subarachnoid space into the venous system. This is a crucial process in the circulation of CSF, maintaining a balance between the amount of CSF produced and the amount absorbed.

Clinical significance[edit | edit source]

Arachnoid granulations can become enlarged or hypertrophic in certain conditions, such as idiopathic intracranial hypertension. This can lead to the formation of arachnoid cysts, which can cause symptoms such as headaches, seizures, and visual disturbances.

See also[edit | edit source]

References[edit | edit source]


Arachnoid granulation Resources
Doctor showing form.jpg
Wiki.png

Navigation: Wellness - Encyclopedia - Health topics - Disease Index‏‎ - Drugs - World Directory - Gray's Anatomy - Keto diet - Recipes

Search WikiMD


Ad.Tired of being Overweight? Try W8MD's physician weight loss program.
Semaglutide (Ozempic / Wegovy and Tirzepatide (Mounjaro) available.
Advertise on WikiMD

WikiMD is not a substitute for professional medical advice. See full disclaimer.

Credits:Most images are courtesy of Wikimedia commons, and templates Wikipedia, licensed under CC BY SA or similar.

Contributors: Admin, Prab R. Tumpati, MD