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Lumbar puncture

A 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, medication, or a contrast dye (for spinal X-rays) into the spinal fluid or to drain fluids that accumulate as a result of certain medical conditions.

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

A lumbar puncture is also sometimes called a spinal tap.

Author Jeannette Curtis
Author Caroline Rea, RN, BS, MS
Editor Kathleen M. Ariss, MS
Editor Susan Van Houten, RN, BSN, MBA
Associate Editor Tracy Landauer
Associate Editor Pat Truman
Primary Medical Reviewer Patrice Burgess, MD
- Family Medicine
Primary Medical Reviewer Adam Husney, MD
- Family Medicine
Primary Medical Reviewer Kathleen Romito, MD
- Family Medicine
Last Updated May 25, 2007

WebMD Medical Reference from Healthwise

Last Updated: May 25, 2007
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