Arachnoid granulations are small, finger-like projections of the arachnoid mater, one of the three layers of membranes that protect the brain and spinal cord. They protrude into the dural sinuses, which are large veins that drain blood from the brain. These granulations play a crucial role in the absorption of cerebrospinal fluid (CSF) into the bloodstream, helping to maintain proper fluid balance in the central nervous system. These structures are primarily found along the superior sagittal sinus, a major vein located at the top of the brain. By facilitating the transfer of CSF, arachnoid granulations help regulate intracranial pressure and ensure that the brain remains cushioned and protected from injury.