The arachnoid villi allow cerebrospinal fluid to pass between which two of the following spaces?
The arachnoid villi are extensions of the arachnoid mater into the superior sagittal sinus. The villi allow for proper drainage of the CSF into the venous bloodstream from the subarachnoid space in which the CSF circulates. The villi are a crucial element in maintaining proper intracranial pressure and circulation of the CSF.