This test looks at the fluid called cerebrospinal fluid (CSF) that surrounds the brain and spinal cord. It is done for a number of different reasons.  It can be done to look for diseases of the brain and nervous system or it can look for cancer cells.  It may also be done to give treatment, including chemotherapy and pain relieving drugs, or to measure the pressure of the fluid, or to look for infections.

what happens?

You or your parents will be asked to sign a consent form to give permission for the doctors to do the test.

It is done either by a doctor or sometimes by a specialist nurse who will have had training.

You will be asked either to sit and bend over or to lie on your side with your knees bent up. The skin is cleaned with antiseptic which will feel cold and you will be given a local anaesethetic to numb the area where the needle is put in to collect the fluid. They will then wait a few minutes for that to work. You will be asked to lie very still. You will feel some pressure or pushing as the needle is inserted between two of the bones in your back (vertebrae). The fluid is drawn out and the needle is then removed and a dressing put over the site. This all takes about 20 minutes. The dressing can be removed the next day. The nurses will check you afterwards to make sure you are okay for a few hours.

It shouldn’t be painful but you may feel uncomfortable.

afterwards

You may have a headache. You can have pain killers for this. You will be asked to stay lying down for a few hours afterwards, exactly how long depends on how you feel. The doctor or nurse will tell you when you can go and you should then be able to carry on as normal.

If you are having a lumbar puncture in order to have chemotherapy or a painkiller, the drug will be given into the needle instead of the fluid being removed.