Spine tumors can be benign or malignant. Most malignant tumors are metastatic and spread to the spine from other primary locations such as breast, lung, prostate, melanoma, etc. Benign tumors tend to arise directly from the tissue they are attached. Fortunately, most intra-dural tumors are benign.
The dura is the membrane covering the brain and spinal fluid. Within the dura is the brain, spinal cord and caudal equina. The dura is the barrier that contains the spinal fluid.
This video demonstrates removal of a large benign tumor from the dura in the lumbar spine. It demonstrates what the nerves look like and how each nerve is associated with a tiny artery that provides nutrition to the nerve. CSF (spinal fluid) is seen flowing in the dura throughout the 2+ hour operation. The brain produces nearly a quart of spinal fluid daily. If spinal fluid is not readily seen bathing the nerves throughout surgery, then a blockage is usually found above the surgery site. This blockage may be another tumor, spinal stenosis, or arachnoiditis.