Lumbar puncture

A lumbar puncture is a special test where a needle is inserted into the lower part of your spine to remove some spinal fluid.

This test is used to look for conditions affecting the spine, your brain or your nervous system. It is often used to help diagnose or exclude important conditions such as meningitis, subarachnoid haemorrhage and neurological condition eg Gullian-Barre Syndrome and multiple sclerosis.undefined

A lumbar puncture can also be used to deliver antibiot
ics or chemotherapy medication directly to the cerebrospinal fluid in a person's spine.

How is it done?

No preparation is needed. You will have a small local anaesthetic injection into the skin before a needle is inserted between two vertebrae (back bones) into the spinal canal. You will lie on your side, legs pulled up with your chin tucked in, or you may be seated and leaning forward. This helps open up the space between the vertebrae. Once the needle is in the right place, a few drops of cerebrospinal fluid are collected into a sterile container and sent to the lab. If needed, the spinal pressure can also be measured. 

  • The needle is only in your back for a few minutes although the whole procedure takes 20-45 minutes.
  • You will have a small plaster over the exit point.
  • Once finished, you will need to remain lying down for another 30 minutes or so and it is best to rest for several hours to reduce the risk of getting a headache.

Risks

There is  little risk of any major complication due to the procedure, however some patients will experience a headache within the next 24-48 hours. This can be treated by drinking plenty of fluids and taking a painkiller such as paracetamol.  There may also be some soreness in the area around the needle insertion point. 

Results 

Some results are available within an hour while others take longer, perhaps 48 hours. Your doctor will explain the result.

Learn more

Lumbar puncture factsheet Kids Health NZ
Lumbar puncture NHS Choices

Credits: Health Navigator. Reviewed By: Health Navigator