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Home > Health Library > Spinal tap (lumbar puncture)
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.
Current as of: April 8, 2021
Author: Healthwise Staff
Medical Review:E. Gregory Thompson MD - Internal Medicine & Adam Husney MD - Family Medicine & Martin J. Gabica MD - Family Medicine
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