What is Lumbar Puncture?

Definition of Lumbar Puncture (or Spinal Tap)

A lumbar puncture, or spinal tap, is a procedure performed to collect a sample of cerebrospinal fluid (CSF), which surrounds the brain and the spinal cord. A needle is inserted into the lower back, and CSF is collected for further study.

Purpose of the Test

This test helps to identify many neurological disorders, diseases, infections and injuries:

  • Meningitis
  • brain bleeding
  • diagnose MS or Guillain-Barré syndrome
  • measure CSF pressure
  • inject a radioactive dye for further x-ray or nuclear tests

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When you visit the Neurology Institute of San Antonio, be sure to ask about the neurological tests we can provide to our patients, like an MRI.