Lumbar Puncture
(Medical procedures and examinations)
This topic will help you learn more about the lumbar puncture and how to prepare for it.
What is a lumbar puncture?
A lumbar puncture, also called a spinal tap, is a procedure performed by inserting a needle into the lower back to obtain a sample of cerebrospinal fluid (CSF), which surrounds the spinal cord and brain.
- When is a lumbar puncture performed?
- A doctor may perform a lumbar puncture to test for the following:
- Bleeding in the brain (intracranial hemorrhage).
- Dementia.
- Leukemia or othertypes of cancer.
- Meningitis and encephalitis (infections of the brain and spinal cord).
- Multiple sclerosis or other autoimmune disorders.
- Myelitis (inflammation of the spinal cord).
- Excess cerebrospinal fluid.
- Administration of regional anesthesia, such as epidural anesthesia, to prevent pain in the lower part of the body.
- Injection of dye for diagnostic X-ray testing (myelography).
Injection of cancer medications or muscle relaxants.
Relief of intracranial (head) pressure.
- How do you prepare for a lumbar puncture?
- Your doctor may ask you to have a blood test before the procedure to make sure your blood clots normally. You should follow your doctor’s instructions on what to do before the procedure. In general:
- Inform your doctor if you are allergic to povidone-iodine (antiseptic) or procaine (anesthetic).
- Your doctor may ask you to temporarily stop taking any medication that could increase the risk of bleeding during the procedure.
