A lumbar puncture is a medical procedure where a needle is inserted into the lower part of the spine totest for conditions affecting the brain, spinal cord or other parts of the nervous system.

During the procedure, pressure is measured and samples of cerebrospinal fluid (CSF) are taken from inside the spine. CSF is a clear, colourless fluid that surrounds and supports the brain and spinal cord. Analysis of CFS can often reveal a good deal about some conditions that affect the brain and spinal cord.

The fluid can be tested to help diagnose conditions, such as:

  • Meningitis an infection of the layers (membranes) surrounding the brain and spinal cord
  • subarachnoid haemorrhage a type of stroke, caused by bleeding in and around the brain
  • Guillain-Barr syndrome a rare condition that causes inflammation of the nerves in the arms and legs

A lumbar puncture doesn't necessarily mean you have one of these conditions; it may be used to rule them out.

A lumbar puncture can also be used to treat some conditions, such as injecting antibiotics or chemotherapy medication into the CSF.

The pressure within the spinal canal is usually measured and some CSF is removed either to reduce the pressure or for a sample to be sent for testing.

You will normally be lying on your side, with your legs pulled up and your chin tucked in, but sometimes the procedure is carried out while youre seated and leaning forwards.

It usually takes around 30-45 minutes to complete.

Its possible to get results on CSF samples within 48 hours, but specialised tests can take several weeks.

This occurs internally, so you wont see it.

The headaches are typically worse when in the upright position and can usually be relieved by lying down. Drinking plenty of fluids and taking simple painkillers will also help. It can take up to a week for the hole to heal and the fluid to stop leaking.


Content supplied by the NHS Website

Medically Reviewed by a doctor on 28 Nov 2016