A dural sinus is a channel found within the dura mater, the outermost layer of the protective membranes surrounding the brain and spinal cord. These sinuses collect and drain blood from the brain, as well as cerebrospinal fluid, back toward the heart. They play a crucial role in maintaining proper blood circulation within the central nervous system. There are several major dural sinuses, including the superior sagittal sinus and the transverse sinus. These sinuses are lined with endothelial cells and are not true veins, but they function similarly by facilitating the return of deoxygenated blood from the brain to the internal jugular vein.