There seems to be about thirty percent of patients who have lumbar punctures that experience a headache afterward. Lumbar punctures are also known as spinal taps which is a procedure where a small needle is inserted in the membrane next to the spinal cord in your lower back so cerebrospinal fluid can be drawn out.
When a headache develops, it is usually caused by the spinal fluid leaking out when the needle gets inserted. A headache from the spinal tap is often throbbing, dull, and will get worse when you stand or sit up.
These headaches, sometimes called post-dural puncture headaches (PDPH), are a common complication not only after lumbar punctures but also following spinal anesthesia or an accidental puncture during an epidural. They’re often positional—meaning they tend to improve when you’re lying flat and worsen when you’re upright.
Alongside the aching head, you might notice other symptoms such as neck stiffness, sensitivity to light, nausea, or even a bit of ringing in your ears. Occasionally, people mention blurred or double vision as well. All these symptoms are part of the body’s response to the disruption in spinal fluid pressure after the procedure. Your pain can be mild or range all the way to completely debilitating along with making you dizzy, your ears may ring, your vision may be blurred, or you might see double, and you may have a stiff neck or nausea.
Why Do Some People Get a Headache After a Spinal Tap—and Others Don’t?
Now, you might be wondering why not everyone who gets a spinal tap ends up with a pounding headache—or why a few unlucky souls develop symptoms even when their spinal fluid pressure looks normal. The real answer is, it’s a bit of a mystery.
Here’s what medical folks believe: That headache happens when your cerebrospinal fluid (CSF) escapes a little too quickly through the tiny hole left by the needle, dropping the pressure. When you stand up, gravity pulls on your brain and nerves just enough to make things hurt more.
However, it’s not a straightforward recipe. Some patients might have a decent leak but never notice a thing, while others get hit with a splitting headache even if tests show their CSF pressure isn’t especially low. Your body’s unique response, how much fluid leaks, and individual sensitivity all play a part—which means there’s no one-size-fits-all outcome after a lumbar puncture.
What Does Imaging Show About Post-Dural Puncture Headaches?
When it comes to figuring out what’s actually happening inside your head after a lumbar puncture, imaging tools like MRI have shed some light. These scans have shown that when spinal fluid leaks out, the drop in fluid pressure causes the blood vessels in the brain’s protective coverings (the meninges) to swell and expand to make up for the loss.
That swelling can quickly lead to the headache pain. In fact, doctors can sometimes spot these changes—such as stretched veins or an increase in blood volume—on an MRI. This all fits with the symptoms most people describe: throbbing and pressure that get worse when standing up. MRIs taking a peek while you’re in the midst of one of these headaches really help confirm what’s going on behind the scenes.
Preventing Spinal Headaches
Most lumbar punctures are executed to be able to diagnose conditions like meningitis which is an infection of the meninges of the brain and other infections of your central nervous system; diseases of the neurological system that might be causing headaches from high pressure, Guillain-Barre’ syndrome, multiple sclerosis, some disorders of your peripheral nerves, or cancers of the brain. Sometimes they are used to give spinal anesthesia for surgery.
To prevent a headache after a spinal tap is for your doctor to utilize what is called an atraumatic needle because it will be less likely to let the spinal fluid leak out. Your brain is floating in spinal fluid all the time, and if a leak occurs it will reduce the volume of what is inside your skull, causing your brain matter to be able to sag inside your skull, and that can trigger your headache.
When this happens, the loss of spinal fluid—also called CSF hypotension—causes your body to try to compensate. The blood vessels in the lining of your brain (the meninges) expand and the veins dilate to make up for the lost fluid, which leads to increased blood volume in that area. This sudden venous distention is what actually creates the throbbing pain of a spinal headache. In fact, this process can even be seen on MRI scans in people who develop these post-lumbar puncture headaches.
Treating Spinal Headaches
If you start getting a headache after you have had a spinal tap, let your doctor know as soon as possible so she or he can prescribe an oral painkiller for you. Most of the time, your headache will get better by itself; staying hydrated, resting, and drinking caffeinated drinks will help relieve the pain. If you notice the pain is worse when you sit up or stand, lying down might be the best.
Risk Factors
It seems that some people are more likely to have this kind of headache. The group more likely to succumb to this type of a headache includes females, people who have a history of headaches, those in the age group of 30 – 50 years, and people who are thin.
Follow-Up Treatment
If that headache does not let up, you may benefit from fluids, intravenous caffeine, and bed rest. If it should get worse, a neurologist can perform what is called epidural blood patching. It is a procedure that will require drawing some blood from you, the patient, and injecting it back into your spinal canal in your lower back outside the dura. By placing the patch it will raise the fluid level, and most of the time it will relieve a headache. Sometimes, the doctor might have to repeat this procedure to achieve complete relief.
If that doesn’t get rid of the headache, doctors can use surgical glue and patch the hole from where the spinal fluid is leaking, or they can surgically close the hole with stitches.