Lumbar Puncture Fact Sheet

Cerebrospinal Fluid (CSF) is collected through a procedure called a lumbar puncture. A lumbar puncture allows us to collect a small amount of your CSF so that we may test it for markers of immune function, markers of Alzheimer’s disease (AD) related proteins, and other aging biomarkers. These markers may one day help us learn how early changes in the spinal fluid relate to cognitive decline.

Why is a spinal fluid sample important for our research?

The cerebral spinal fluid contains numerous proteins, including inflammatory markers and other immune related health markers. It also contains proteins called tau and amyloid that are the building blocks of the plaques and tangles that are the hallmark biomarkers for Alzheimer’s disease. We can get a good idea of how much of these proteins are accumulating in your brain by looking at the amount in your spinal fluid. 

What is a Lumbar Puncture?

A lumbar puncture involves placing a needle between the bones of the lower back, below the end of the spinal cord, to draw the fluid known as cerebrospinal fluid or CSF.  This fluid bathes the brain and contains the proteins of interest and other molecules that are markers of brain health and disease. 

Before Your Visit

The main risk of the lumbar puncture procedure is a headache following the procedure.  Being well hydrated (drinking plenty of water) both before and after your procedure may decrease the risk of headache. 

During Your Visit

The clinician will decide where to insert the needle by feeling the spaces between the bones in your lower back.  The clinician will create a sterile environment and prepare your back for the procedure.  Then sterile sheets will be draped over your back. 

Next, your lower back will be numbed with a drug called Lidocaine.  The clinician will place a thin spinal needle between the spaces in your back, below where the spinal cord ends.  This space contains spinal fluid.  Approximately five teaspoons of spinal fluid will be removed and the needle withdrawn.  You will feel pressure as the clinician inserts the needle.  Let the clinician know if you feel any pain.  Breathe deeply and slowly.  During the collection of the CSF, the clinician will use a syringe to remove the fluid.  Once enough fluid has been taken for testing, the needle will be pulled out.  A band-aid will be placed over the site which you can take off the next day.  The entire test, including the preparation of the sterile environment, usually lasts about 30 to 40 minutes. 

The most common complication of spinal fluid collection is a headache. The number of people who get severe headaches with this procedure is less than 1 out of every 100 people (1%).

After the procedure, you will be given fluids to drink.  These fluids will help to replace the CSF fluid that was taken during the procedure.  The clinician will check the puncture site after the 20-minute rest period.

After Your Visit

  • Keep drinking plenty of fluids (e.g. water, juice, etc.) for two days after the procedure
  • The morning after the test, you may take a bath or shower and remove the band-aid.
  • If you get a headache after starting activity, return to resting and increase your intake of fluids and caffeine.
  • You may feel lower back pain for 1-2 days after the procedure.  You may take over the counter analgesics (ibuprofen, Tylenol, naproxen) to help with any discomfort you experience.
  • You should avoid heavy lifting, bending, or strenuous exercise that involves the lower back for 48 hours after the test.
  • You should avoid travel (e.g. flying in an airplane) for 2 days following the procedure