Some problems can cause CSF to leak out through a hole or tear in the dura mater (the layer of the meninges that is next to the skull and the bones of the spinal cord). CSF leaks are usually a complication of a lumbar puncture or certain kinds of surgery on the head, neck, or brain. However, an injury to the head or spine can also cause a CSF leak. Sometimes, doctors cannot find a cause for a CSF leak.