A small amount of CSF is typically collected so it can be studied thoroughly in a lab.
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.
Illustration by Emily Roberts, Verywell
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.
For treatment of this condition, CSF fluid is removed to decrease the pressure.
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.
For conditions such as MS or chronic headaches, the procedure is usually scheduled in advance.
You may also have a CT scan or MRI beforehand.
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.
Let your healthcare provider know about any other medications, supplements, or herbal remedies you’re taking.
Pre-Test
You may need to fill out a consent form before you have this procedure.
If you will have your CSF pressure measured, this is done while you are lying on your side.
These positions widen the area between your lumbar bones (vertebrae), allowing for easier access.
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.
When anesthetics are injected, it’s calledspinal anesthesia.
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.
Keep drinking water to check that you stay hydrated.
Your healthcare provider may give you more specific instructions.
Headaches can begin a few hours up to two days after your spinal tap.
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.
If you are having a CSF culture, the results will take days or longer.
This helps them know which treatment you’re gonna wanna 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.
Treatment may include radiation, chemotherapy, immunotherapy, and medications to help control your symptoms.
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.
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