Spinal tap (lumbar puncture)

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A spinal tap (lumbar puncture) is a procedure in which a needle is inserted into the spinal canal to measure the pressure and obtain a sample of cerebrospinal fluid (CSF), the colorless fluid that surrounds the brain and spinal cord. The procedure may also be used to inject anesthetics, medicine, or a contrast dye (for spinal X-rays) into the spinal fluid. And it may be used to drain fluids that build up as a result of certain medical conditions.

Fluid samples obtained from a spinal tap can be analyzed for signs of infection (such as meningitis), inflammation, cancer, or bleeding in the area around the brain or spinal cord.

The Health Encyclopedia contains general health information. Not all treatments or services described are covered benefits for Kaiser Permanente members or offered as services by Kaiser Permanente. For a list of covered benefits, please refer to your Evidence of Coverage or Summary Plan Description. For recommended treatments, please consult with your health care provider.