A lumbar puncture is a diagnostic test for multiple sclerosis that involves removing and analysing a sample of cerebrospinal fluid (CSF), the fluid that surrounds the brain and spinal cord within the skull and backbone. We know that the thought of having a lumbar puncture can sometimes make people feel uneasy and leave them with lots of questions. In this video Professor Coles talks us through how and why a lumbar puncture is performed when you are trying to diagnose MS. Further information here