Brief Description of Procedure: 

This test is used to check for bleeding, hemorrhage, infection, or other disorder of the brain, spinal cord, and nerves. In this test, the lower back is numbed with local anesthesia and a thin needle is placed into the space that contains the spinal fluid. The amount of spinal fluid that is needed for the tests is removed and the needle is withdrawn. Discomfort may be associated with this test.