Lumbar Puncture (Spinal Tap)

A lumbar puncture, also called a spinal tap, is an image-guided procedure performed on the lower back which removes fluid that surrounds the brain and spinal cord to examine it for cancer cells or infection. This fluid is called cerebrospinal fluid or CSF and is a clear liquid that delivers nutrients to the brain and cushions the spinal cord and brain. A lumbar puncture may also be performed to inject medication into this the spinal column. Children and adolescents are usually given anesthesia or sedation before a lumbar puncture is performed.

Lumbar Puncture Spinal Tap

Performing the Procedure

  • A child will usually lie on his or her side, chin tucked to the chest and knees pulled up to the chest. A staff member will help your child get into the proper position and support that position throughout the procedure.
  • Lying still can be stressful for children. Rehearsing the position before the test can help your child feel more in control and understand what he or she needs to do.
  • In some cases, older children can sit up and curl the back by tucking the chin to the chest.
  • When the back is in a curved position, a needle is placed between the bones of the spine (vertebrae) below the level of the spinal cord.
  • Fluid from the spinal canal is then removed through the needle and collected into a tube that is sent to a laboratory to be tested.
  • For some types of cancer, chemotherapy may be given into the spinal canal through the same needle after the cells are removed for testing.