Medically reviewed by Sameena Zahoor, MDMedically reviewed by Sameena Zahoor, MD The meninges of the brain and spinal cord are three layers of membranes: the dura mater, arachnoid mater ...

A CSF leak occurs when the fluid escapes through a tear or hole in the dura mater—the tough, outermost layer of the meninges that surrounds the brain and spinal cord. The dura can be damaged ...