Table of ContentsView AllTable of ContentsPurposeSide Effects/RisksWarningsBefore the TestDuring the TestAfter the TestInterpreting ResultsA Word From Verywell
Table of ContentsView All
View All
Table of Contents
Purpose
Side Effects/Risks
Warnings
Before the Test
During the Test
After the Test
Interpreting Results
A Word From Verywell
A lumbar puncture (LP), which is also called a spinal tap, is a common neurological test that’s done to examine thecerebrospinal fluid(CSF)—the protective fluid that surrounds your brain and spinal cord. During the procedure, a needle is carefully inserted between the bones of thelumbar spine, which is in the lower back. A small amount of CSF is typically collected so it can be studied thoroughly in a lab. This procedure is used to help diagnose a wide variety of disorders, and it can be a treatment for certain conditions too.
Purpose of the Test
Usually, an LP is performed to run diagnostic tests on the CSF. This helps with the diagnosis of certain diseases and with following the progression of some neurological disorders.
A spinal tap is commonly used to diagnose potentially life-threatening infections of the central nervous system.Diagnosing meningitis(inflammation of the membranes around the brain and spinal cord) is the most common reason for a lumbar puncture.
Meningitiscauses a stiff neck, sudden high fever, severe headache, confusion, seizures, sleepiness, nausea, vomiting, and loss of appetite.Bacterial meningitisneeds to be treated promptly to prevent serious complications.
Diagnosing asubarachnoid hemorrhage, which is bleeding in between the meninges, is another common reason for an LP. Acomputed tomography (CT) scanis normally performed first, but it may not always show the hemorrhage. When this is the case, a lumbar puncture is usually ordered next to look for blood. This condition can lead to brain damage or death and needs to be treated as soon as possible.
Other conditions that a lumbar puncture can help diagnose include:
This procedure may also be done to measure the CSF pressure around the spinal cord and brain, which helps with the diagnosis ofpseudotumor cerebri, a condition that causes increased pressure around the brain. For treatment of this condition, CSF fluid is removed to decrease the pressure.
For people with problems such as severescoliosis,arthritis, orobesity, an LP might requirefluoroscopic guidance,which means that it is done while the doctor is using X-ray technology to visualize the spine.Some healthcare providers prefer to use fluoroscopic guidance with every patient to assist them in viewing the needle as it’s placed.
Side Effects and Risks
The side effects and risks associated with a lumbar puncture include:
Despite many people’s fears, there is almost no chance of spinal cord damage or paralysis from an LP because the needle is inserted in the spinal canal well below where thespinal cordends. The spine (backbone) is longer than the spinal cord, so there is plenty of space in your spinal canal that is not near your spinal cord.
Contraindications
Fluoroscopy is not recommended for women who are pregnant or think they could be pregnant. Special precautions may be taken or a different kind of test may be done instead.
Absolute ContraindicationsSkin infection near the site of the lumbar punctureUncorrected bleeding disordersAcute spinal cord traumaSuspicion of increased intracranial pressure due to a mass in the brain
Absolute Contraindications
Skin infection near the site of the lumbar punctureUncorrected bleeding disordersAcute spinal cord traumaSuspicion of increased intracranial pressure due to a mass in the brain
Sometimes an LP is done as an emergency procedure, such as when there is concern about meningitis or cancer metastasis. For conditions such as MS or chronic headaches, the procedure is usually scheduled in advance.
Before your procedure, your healthcare provider will order blood tests to make sure that your blood clots as it should and that your kidneys are functioning well. You may also have a CT scan or MRI beforehand.
Be sure to tell your healthcare provider if you’re allergic to any medications, especially local or general anesthesia.
Timing
An LP normally takes around 15 minutes, and you’ll be asked to lie down for another hour or two afterward to avoid a spinal headache.
Location
The procedure can be done on an outpatient basis at a hospital or clinic. If you’re already in the hospital or emergency room, it may be performed at your bedside.
What to Wear
You’ll be given a gown to wear for this procedure and you’ll be asked to take off any jewelry, piercings, or accessories that could interfere with the test.
Food and Drink
Your healthcare provider will talk to you about food and drink restrictions before the procedure. If you will need to have general anesthesia, you will have to refrain from eating or drinking anything for several hours or more before the procedure.
In an emergency situation or if you will only need to have numbing medication placed in the skin around your back, these restrictions won’t apply.
Medications
If you takeblood-thinnerslike warfarin, clopidogrel, or heparin or nonsteroidal anti-inflammatory drugs (NSAIDs) like aspirin, ibuprofen, or naproxen, you may need to stop these several days beforehand to reduce the risk of bleeding.
Let your healthcare provider know about any other medications, supplements, or herbal remedies you’re taking.
Cost and Health Insurance
The price of an LP can range from $400 to $4000 or more, depending on factors like where you’ll have it and what tests will be run.
If you have health insurance, the cost should be covered, but you may want to check with your insurance provider to make sure and to find out about any co-pay or co-insurance for which you may be responsible.
What to Bring
If you are going in for a scheduled test, bring your insurance card and a form of identification with you.
If you are having this test as an outpatient, you will need someone to drive you home after the procedure, so be sure to bring along a friend or family member, or arrange for a service to pick you up when you’re done.
A neurologist or a radiologist will perform your lumbar puncture and there may be an assistant there as well.
Pre-Test
You may need to fill out a consent form before you have this procedure.
You’ll need to change out of your clothes into a gown and then lie on your side on a table or your hospital bed in a fetal position with your knees tucked up toward your chest. If you will have your CSF pressure measured, this is done while you are lying on your side.
Alternatively, you may be asked to sit on the edge of the table or bed and bend forward, leaning on something stable with your back to the healthcare provider. These positions widen the area between your lumbar bones (vertebrae), allowing for easier access.
If your child is the one having the lumbar puncture, they may have intravenous (IV) sedation at this time.
Throughout the Test
The spinal tap takes about 15 minutes, plus recovery time.
The discomfort level during an LP can vary, but it’s usually mild to moderate.
Once the needle is in place, what happens depends on why you’re having the LP.
A similar procedure is used to inject chemotherapy, contrast dye for an imaging test, antibiotics, or anesthetics for surgery. When anesthetics are injected, it’s calledspinal anesthesia. During these procedures, the needle is not inserted into the meninges and remains above this protective tissue without puncturing it.
Post-Test
You may be asked to lie down flat for an hour or two after this procedure. You’ll also be given fluids to help prevent a low-pressure headache.
If you’re being discharged home, you’ll be able to go home with your driver.
You’ll need to take it easy for the rest of the day, and it’s a good idea to lie down if possible. Keep drinking water to make sure you stay hydrated. Your healthcare provider may give you more specific instructions.
Managing Side Effects
You may notice some back pain, numbness, or soreness that can feel like it’s radiating down your legs for a few days. If it’s bothersome, but mild, try over-the-counter pain relievers such as Tylenol (acetaminophen) to help relieve the discomfort.
If you experience a headache after a spinal tap, Tylenol (acetaminophen) or caffeine can help. Try lying down since being upright can make the pain worse.
Sometimes the headache is severe or persists for a few days to a week after the lumbar puncture—this may mean that the needle has left a hole in your thecal sac and fluid is still leaking out. In this case, a procedure called an epidural blood patch—in which your own blood is injected into the spinal canal—may relieve your headache as it slows down the leakage.
When to Call Your Healthcare ProviderIf a severe headache persists a day or two despite treatmentIf you experience numbness or tingling in your legsIf you have a high fever (over 100.4 F)If there is bleeding or discharge from the injection siteIf you are unable to urinate
When to Call Your Healthcare Provider
If a severe headache persists a day or two despite treatmentIf you experience numbness or tingling in your legsIf you have a high fever (over 100.4 F)If there is bleeding or discharge from the injection siteIf you are unable to urinate
Your test results may take several days or weeks to come back, depending on the type of test that’s being done. If you are having a CSF culture, the results will take days or longer. Simple test results, such as a white blood cell (WBC) count or red blood cell (RBC) count, may be available within an hour.
The CSF can be tested for:
When combined with other test results, as well as your symptoms, medical history, and physical exam, the information from an LP can help pinpoint a diagnosis.
In cases where you have an infection like meningitis or encephalitis, testing your CSF can tell your healthcare provider whether your infection is bacterial, viral, or fungal. This helps them know which treatment you need to take.
You may need additional testing to figure out the specific cause of your symptoms. For possibleMS, an LP alone can’t diagnose this, so you may also have an MRI.
If you already had additional tests and the LP test result helped to confirm a specific diagnosis, your healthcare provider will discuss a treatment plan with you.
If your healthcare provider thinks you have leptomeningeal disease, a rare condition in which late-stage cancer has spread to the membranes around your brain and spinal cord, you will need at least three separate lumbar punctures to rule this out. Treatment may include radiation, chemotherapy, immunotherapy, and medications to help control your symptoms.
Be sure to talk to your healthcare provider about any questions or concerns you have regarding this test or your diagnosis.
An LP, while uncomfortable, is not as bad as most people’s fear. In most cases, the worst part is the pinch felt with the injection of the numbing medicine. While complications can occur, they are very infrequent. The benefits of obtaining the fluid for testing usually outweigh the risks and discomfort of the procedure.
11 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Costerus JM, Brouwer MC, Van de beek D.Technological advances and changing indications for lumbar puncture in neurological disorders.Lancet Neurol.2018;17(3):268-278.doi:10.1016/S1474-4422(18)30033-4Carpenter CR, Hussain AM, Ward MJ, et al.Spontaneous subarachnoid hemorrhage: A systematic review and meta-analysis describing the diagnostic accuracy of history, physical examination, imaging, and lumbar puncture with an exploration of test thresholds.Acad Emerg Med. 2016;23(9):963-1003. doi:10.1111/acem.12984Doherty CM, Forbes RB.Diagnostic lumbar puncture.Ulster Med J. 2014;83(2):93-102.Özütemiz C, Rykken JB.Lumbar puncture under fluoroscopy guidance: a technical review for radiologists.Diagn Interv Radiol. 2019;25(2):144-156. doi:10.5152/dir.2019.18291Pirbudak L, Özcan HI, Tümtürk P.Postdural puncture headache: Incidence and predisposing factors in a university hospital.Agri. 2019;31(1):1-8. doi:10.5505/agri.2018.43925Mcdowell KE, Chapman ALN.Cerebral herniation after lumbar puncture.Clin Infect Dis. 2019;69(7):1266-1267. doi:10.1093/cid/ciz130Memorial Sloan Kettering Cancer Center.About Your Lumbar Puncture.Canadian Cancer Society.Lumbar puncture.White B, Lopez V, Chason D, Scott D, Stehel E, Moore W.The lumbar epidural blood patch: A Primer.Appl Radiol.2019;48(2):25-30.Kim WH, Racine AM, Adluru N, et al.Cerebrospinal fluid biomarkers of neurofibrillary tangles and synaptic dysfunction are associated with longitudinal decline in white matter connectivity: A multi-resolution graph analysis.Neuroimage Clin.2019;21:101586. doi:10.1016/j.nicl.2018.10.024Leal T, Chang JE, Mehta M, Robins HI.Leptomeningeal metastasis: Challenges in diagnosis and treatment.Curr Cancer Ther Rev. 2011;7(4):319-327. doi:10.2174/157339411797642597Additional ReadingJohns Hopkins Medicine.Lumbar Puncture.Johnson KS, Sexton DJ.Lumbar Puncture: Technique, Indications, Contraindications, and Complications in Adults. UpToDate.Nayar G, Ejikeme T, Chongsathidkiet P, et al.Leptomeningeal disease: Current diagnostic and therapeutic strategies.Oncotarget. 2017;8(42):73312-73328. doi:10.18632/oncotarget.20272.Radiological Society of North America, Inc. (RSNA).Lumbar Puncture. RadiologyInfo.org.Silberstein SD.Low-Pressure Headache. Merck Manual: Consumer Version.
11 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Costerus JM, Brouwer MC, Van de beek D.Technological advances and changing indications for lumbar puncture in neurological disorders.Lancet Neurol.2018;17(3):268-278.doi:10.1016/S1474-4422(18)30033-4Carpenter CR, Hussain AM, Ward MJ, et al.Spontaneous subarachnoid hemorrhage: A systematic review and meta-analysis describing the diagnostic accuracy of history, physical examination, imaging, and lumbar puncture with an exploration of test thresholds.Acad Emerg Med. 2016;23(9):963-1003. doi:10.1111/acem.12984Doherty CM, Forbes RB.Diagnostic lumbar puncture.Ulster Med J. 2014;83(2):93-102.Özütemiz C, Rykken JB.Lumbar puncture under fluoroscopy guidance: a technical review for radiologists.Diagn Interv Radiol. 2019;25(2):144-156. doi:10.5152/dir.2019.18291Pirbudak L, Özcan HI, Tümtürk P.Postdural puncture headache: Incidence and predisposing factors in a university hospital.Agri. 2019;31(1):1-8. doi:10.5505/agri.2018.43925Mcdowell KE, Chapman ALN.Cerebral herniation after lumbar puncture.Clin Infect Dis. 2019;69(7):1266-1267. doi:10.1093/cid/ciz130Memorial Sloan Kettering Cancer Center.About Your Lumbar Puncture.Canadian Cancer Society.Lumbar puncture.White B, Lopez V, Chason D, Scott D, Stehel E, Moore W.The lumbar epidural blood patch: A Primer.Appl Radiol.2019;48(2):25-30.Kim WH, Racine AM, Adluru N, et al.Cerebrospinal fluid biomarkers of neurofibrillary tangles and synaptic dysfunction are associated with longitudinal decline in white matter connectivity: A multi-resolution graph analysis.Neuroimage Clin.2019;21:101586. doi:10.1016/j.nicl.2018.10.024Leal T, Chang JE, Mehta M, Robins HI.Leptomeningeal metastasis: Challenges in diagnosis and treatment.Curr Cancer Ther Rev. 2011;7(4):319-327. doi:10.2174/157339411797642597Additional ReadingJohns Hopkins Medicine.Lumbar Puncture.Johnson KS, Sexton DJ.Lumbar Puncture: Technique, Indications, Contraindications, and Complications in Adults. UpToDate.Nayar G, Ejikeme T, Chongsathidkiet P, et al.Leptomeningeal disease: Current diagnostic and therapeutic strategies.Oncotarget. 2017;8(42):73312-73328. doi:10.18632/oncotarget.20272.Radiological Society of North America, Inc. (RSNA).Lumbar Puncture. RadiologyInfo.org.Silberstein SD.Low-Pressure Headache. Merck Manual: Consumer Version.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Costerus JM, Brouwer MC, Van de beek D.Technological advances and changing indications for lumbar puncture in neurological disorders.Lancet Neurol.2018;17(3):268-278.doi:10.1016/S1474-4422(18)30033-4Carpenter CR, Hussain AM, Ward MJ, et al.Spontaneous subarachnoid hemorrhage: A systematic review and meta-analysis describing the diagnostic accuracy of history, physical examination, imaging, and lumbar puncture with an exploration of test thresholds.Acad Emerg Med. 2016;23(9):963-1003. doi:10.1111/acem.12984Doherty CM, Forbes RB.Diagnostic lumbar puncture.Ulster Med J. 2014;83(2):93-102.Özütemiz C, Rykken JB.Lumbar puncture under fluoroscopy guidance: a technical review for radiologists.Diagn Interv Radiol. 2019;25(2):144-156. doi:10.5152/dir.2019.18291Pirbudak L, Özcan HI, Tümtürk P.Postdural puncture headache: Incidence and predisposing factors in a university hospital.Agri. 2019;31(1):1-8. doi:10.5505/agri.2018.43925Mcdowell KE, Chapman ALN.Cerebral herniation after lumbar puncture.Clin Infect Dis. 2019;69(7):1266-1267. doi:10.1093/cid/ciz130Memorial Sloan Kettering Cancer Center.About Your Lumbar Puncture.Canadian Cancer Society.Lumbar puncture.White B, Lopez V, Chason D, Scott D, Stehel E, Moore W.The lumbar epidural blood patch: A Primer.Appl Radiol.2019;48(2):25-30.Kim WH, Racine AM, Adluru N, et al.Cerebrospinal fluid biomarkers of neurofibrillary tangles and synaptic dysfunction are associated with longitudinal decline in white matter connectivity: A multi-resolution graph analysis.Neuroimage Clin.2019;21:101586. doi:10.1016/j.nicl.2018.10.024Leal T, Chang JE, Mehta M, Robins HI.Leptomeningeal metastasis: Challenges in diagnosis and treatment.Curr Cancer Ther Rev. 2011;7(4):319-327. doi:10.2174/157339411797642597
Costerus JM, Brouwer MC, Van de beek D.Technological advances and changing indications for lumbar puncture in neurological disorders.Lancet Neurol.2018;17(3):268-278.doi:10.1016/S1474-4422(18)30033-4
Carpenter CR, Hussain AM, Ward MJ, et al.Spontaneous subarachnoid hemorrhage: A systematic review and meta-analysis describing the diagnostic accuracy of history, physical examination, imaging, and lumbar puncture with an exploration of test thresholds.Acad Emerg Med. 2016;23(9):963-1003. doi:10.1111/acem.12984
Doherty CM, Forbes RB.Diagnostic lumbar puncture.Ulster Med J. 2014;83(2):93-102.
Özütemiz C, Rykken JB.Lumbar puncture under fluoroscopy guidance: a technical review for radiologists.Diagn Interv Radiol. 2019;25(2):144-156. doi:10.5152/dir.2019.18291
Pirbudak L, Özcan HI, Tümtürk P.Postdural puncture headache: Incidence and predisposing factors in a university hospital.Agri. 2019;31(1):1-8. doi:10.5505/agri.2018.43925
Mcdowell KE, Chapman ALN.Cerebral herniation after lumbar puncture.Clin Infect Dis. 2019;69(7):1266-1267. doi:10.1093/cid/ciz130
Memorial Sloan Kettering Cancer Center.About Your Lumbar Puncture.
Canadian Cancer Society.Lumbar puncture.
White B, Lopez V, Chason D, Scott D, Stehel E, Moore W.The lumbar epidural blood patch: A Primer.Appl Radiol.2019;48(2):25-30.
Kim WH, Racine AM, Adluru N, et al.Cerebrospinal fluid biomarkers of neurofibrillary tangles and synaptic dysfunction are associated with longitudinal decline in white matter connectivity: A multi-resolution graph analysis.Neuroimage Clin.2019;21:101586. doi:10.1016/j.nicl.2018.10.024
Leal T, Chang JE, Mehta M, Robins HI.Leptomeningeal metastasis: Challenges in diagnosis and treatment.Curr Cancer Ther Rev. 2011;7(4):319-327. doi:10.2174/157339411797642597
Johns Hopkins Medicine.Lumbar Puncture.Johnson KS, Sexton DJ.Lumbar Puncture: Technique, Indications, Contraindications, and Complications in Adults. UpToDate.Nayar G, Ejikeme T, Chongsathidkiet P, et al.Leptomeningeal disease: Current diagnostic and therapeutic strategies.Oncotarget. 2017;8(42):73312-73328. doi:10.18632/oncotarget.20272.Radiological Society of North America, Inc. (RSNA).Lumbar Puncture. RadiologyInfo.org.Silberstein SD.Low-Pressure Headache. Merck Manual: Consumer Version.
Johns Hopkins Medicine.Lumbar Puncture.
Johnson KS, Sexton DJ.Lumbar Puncture: Technique, Indications, Contraindications, and Complications in Adults. UpToDate.
Nayar G, Ejikeme T, Chongsathidkiet P, et al.Leptomeningeal disease: Current diagnostic and therapeutic strategies.Oncotarget. 2017;8(42):73312-73328. doi:10.18632/oncotarget.20272.
Radiological Society of North America, Inc. (RSNA).Lumbar Puncture. RadiologyInfo.org.
Silberstein SD.Low-Pressure Headache. Merck Manual: Consumer Version.
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