Lumbar Puncture (Spinal Tap)

Frequently Asked Questions

1. Who does a lumbar puncture?

Lumbar puncture is usually done by a doctor who is skilled in the procedure.

2. Why is CSF pressure measured?

CSF pressure reflects the intracranial pressure. Increase in intracranial pressure can be caused by tumor or mass in the brain, swelling of brain and bleeding into the brain, infection and inflammation. Increased intracranial can be life threatening unless promptly diagnosed and treated.

3. Is there any alternative procedure to obtain CSF?

In some persons with infection at the site of lumbar puncture or stiffness of the spine, or spinal trauma, CSF may be obtained from the upper spinal canal via a needle inserted into the back of the neck (cisternal puncture).


4. What are some tests carried out on CSF sample?

Occasionally the appearance of CSF will give a clue as to the possible diagnosis. For example, bloody fluid may signify bleeding in the brain or spinal cord, while cloudy CSF may be a sign of an infection such as meningitis. High CSF pressure may suggest a tumor, bleeding in the brain or swelling, while low pressure may indicate a block in the spinal canal above the puncture site.

The CSF sample will be analyzed in the lab for presence of any abnormalities such as red cells, bacteria, pus cells, white blood cells, antibodies, cancer cells, or excessive protein, and glucose levels.

5. Can multiple sclerosis be diagnosed through a lumbar puncture?

Lumbar puncture is one of the tests done in MS. Other tests are necessary to confirm the diagnosis as the findings of CSF analysis are not specific to multiple sclerosis.

6. What is the outlook following lumbar puncture?

The outlook following a lumbar puncture depends on the condition for which it was done.