Lumbar Punctures

Needle location during a research lumbar puncture. Click anywhere to close the image.
Needle location during a research lumbar puncture. Click anywhere to close the image.

Needle location during a research lumbar puncture. Click anywhere to close the image.

Click on photo to enlarge.

The lumbar punture video can also be accessed on YouTube.

Lumbar punctures, cerebrospinal fluid, and biomarkers—these are three terms that form the horizon of our center’s research. Biomarkers are biological indicators that may lead us to a prevention or cure for Alzheimer’s disease, cerebrospinal fluid is the substance in which some of these biomarkers are found, and a lumbar puncture is the method used to access cerebrospinal fluid.

Often, when we tell people that lumbar punctures are a common part of our research, we are met with a bit of reservation. That reservation is understandable, but we hope that by providing clear information about the procedures and answering some common questions about the procedures, we can help make lumbar punctures seem less invasive and risky.

What is a lumbar puncture?

A lumbar puncture (also called a spinal tap or an LP) is a common medical procedure in which doctors remove a small sample of cerebrospinal fluid (CSF) from a person’s lower back (“lumbar” region). During an LP, participants lie on their side, which allows doctors to easily access the area of the lower back where the LP will occur. Once participants are in position, doctors use a local anesthetic to numb the area and then use a thin needle to draw out a small amount of spinal fluid. Because the anesthetic numbs the area, the LP should not be particularly uncomfortable or painful. After an LP, participants occasionally feel mildly sore as a result of staying in an unfamiliar position during the procedure. If participants are sore after an LP, they can take a standard pain reliever like Tylenol.


Are lumbar punctures safe?

Yes. Our center has improved the procedures for research lumbar punctures and has created safety guidelines that are followed throughout the field. To read more about the safety and acceptability of lumbar punctures, please click here.


 

Will I have a spinal headache after the LP?

We have performed over 2,000 LPs at the UW ADRC and have improved the procedure to reduce discomfort and to minimize the chance of LP-related headaches (known as spinal headaches). In fact, less than one percent of our participants experience significant spinal headaches. However, when they do occur, these headaches can be quite painful. If someone gets a mild headache following an LP, we treat it with Tylenol and beverages that are high in caffeine. In the rare case of a severe headache, we perform a simple medical procedure called an epidural blood patch to relieve the pain. Most spinal headaches can be avoided by following the instructions and follow-up care provided by our physicians. 


What is CSF and why is it so important?

CSF is a clear, colorless liquid that is in direct contact with the brain. It provides a cushion to the brain and spinal cord and may serve some purpose in the chemistry of the brain (which is not clear to us at this point). Importantly, since the CSF interacts very closely with the brain, many researchers believe that it can provide a more direct window into changes that may be occurring there. CSF contains a variety of proteins that researchers measure and analyze. The goal of this analysis is to identify markers (biomarkers) for Alzheimer’s disease that will improve with accurate diagnosis, "preclinical" diagnosis in persons with no memory symptoms who are destined to have Alzheimer's in the future, and monitoring response to therapies. This type of monitoring will be particularly important as we try to develop new treatments. 


What happens to my CSF after it is collected?

At the ADRC, CSF samples are kept within a collection called the ADRC Research Repository. This repository has the largest collection of CSF samples from individuals with no memory complaints (control participants) in the world, and is utilized by a large research community. These samples are particularly important as a group because the collection can be studied for specific research questions related to Alzheimer’s disease.