I recently underwent an exploratory lumbar puncture, and I wanted to share my experiences and talk about why my neurologist and I opted for this somewhat risky procedure. I’ll talk about some of the reasons to undergo exploratory lumbar punctures and how they are performed. I include the guidelines and procedures both you and your doctor will likely be following before during and after the procedure. This way you’ll be prepared and cool as a cucumber the day you or your loved one undergoes this procedure, also known as a spinal tap.
As a sufferer of intractable migraine for over a decade, this is a procedure I have long wanted performed, but been equally afraid to undergo, so I never pushed for it with my old neurologists, who didn’t seem to be taking it at all seriously. It took me a long time to decide the procedure was for me. After finally getting my migraines under control just this past year and realizing it did nothing for the terrible pressure in my head, it had me wondering if more needed to be done than just finding the right migraine medication(s). This ever growing pressure, which became almost unbearable this summer, was accompanied by sharp pain in my head that was positional, intermittent vision and hearing loss, non-stop tinnitus, and a strong pulse in my ears that had the power to turn my tinnitus into the never ending *beeeeep beeeeep beeeeep* of an alarm clock; and the on/off switch seemed to be connected to standing or straining.
Then I had the worst dystonic attack I’ve ever had and things only got worse from there. That’s when my head pain specialist and I knew it was finally time. If I’m being honest, it was probably way past time. You can read more about it here: Why Vacations Don’t Exist for People with MCAS.
Enough about me. Let’s learn more about CSF, lumbar puncture and find out what to expect if you need to undergo the procedure.
The Role of Cerebrospinal Fluid
Cerebrospinal fluid is defined as a “clear watery fluid which fills the space between the arachnoid membrane and the pia mater.” Essentially, it’s the liquid that fills your spinal canal and surrounds your brain and spine. CSF serves several important functions in the central nervous system. CSF cushions the brain and spinal cord against shock. It provides a barrier. It helps to maintain pressure at a constant level inside the skull. Finally, CSF delivers nutrients to the brain and carries waste products away into the bloodstream. CSF is protected and separated from our blood by the blood-brain barrier. There is about 100-150ml of CSF in the normal adult human body. It is primarily made up of water and is alkaline. CSF is continually produced, predominately by the brain’s ventricles, and is entirely replaced every 6 to 8 hours.
An increase in the volume of blood or brain tissue results in a corresponding decrease in the fluid. Conversely, if there is a decrease in the volume of matter within the cranium, as occurs in atrophy of the brain, the CSF compensates with an increase in volume.Cerebrospinal Fluid-Britannica Science
What is a Lumbar Puncture?
A lumbar puncture (LP) is often performed to check for the presence of bacterial, viral and fungal infections, excessive intracranial pressure, a cerebrospinal fluid (CSF) leak, cancers of the brain or spine, subarachnoid hemorrhage (bleeding on the brain), or to aid in the diagnosis of other neurological conditions such as Guillain-Barre syndrome and multiple sclerosis or a mitochondrial disease. LPs can also be performed for injection of chemotherapy or other medications into the spinal canal, as directed by your physician. They can be performed on an emergency basis, such as in the case of injury, or be prearranged, which is often the case with non-emergent exploratory procedures.
A physician usually performs the procedure, however even a well trained nurse practitioner can administer a spinal tap. My own procedure was performed by a nurse practitioner in training who was supervised by a neurologist; he did a fantastic job.
To perform a lumbar puncture, a thin, hollow needle is inserted into the spinal canal. If pressure is a concern, then your neurologist will request a reading of opening and closing pressures. Mine was 14.5 to begin, a middle of the range number that could be too high for some and just right for others. My closing pressures were a 9.5, after they had removed two small vials of CSF to be sent to the lab for testing.
Is Lumbar Puncture Safe?
Spinal taps have a reputation for being a high risk procedure, likely due to early failures during the development of the procedure back in late 19th century. This was in part due to the lack of imaging at the time. Today the procedure is much safer, with the advent of imaging technology, prospective and retrospective study have informed the development of clinical features that are associated with low risks and complications.
In trained hands, Lumbar Puncture is a straightforward procedure with few complications. According to The Health and Social Care Information Centre for England, there were 55,427 episodes of hospital care that included a diagnostic Lumbar Puncture in 2011-12, 0.53% of all hospital consultant episodes, which in Northern Ireland’s health system, with 600,000 admissions annually, would equate to about 8 diagnostic Lumbar Punctures per day.“Diagnostic Lumbar Procedure,” NBCI
Preparing for a Lumbar Puncture
Before administering a lumbar puncture for your symptoms, your doctor may perform additional testing. These can include MRI, CT and blood tests which check for your ability to clot, as well as your kidney function.
Prior to having a LP, your medications will be reviewed, along with any recent illness, medical conditions or allergies. If you think you may be pregnant, you also need to alert your team right away so the necessary precautions can be taken. You may be asked to discontinue the use of any drugs which may thin the blood, from NSAIDs (advil, aleve, toradol, etc.) to heart medications such as Warfarin (Coumadin®), Pradaxa®, Heparin®, Lovenox®, or clopidogrel (Plavix®). Generally speaking, you can expect to be off of these medications anywhere from 3-7 days prior to your procedure to ensure good post-operative clotting of the needle puncture.
In addition to reviewing any and all medications taken, including supplements, any allergies also need to be discussed and you should provide a complete list to your surgical team so they can help to ensure your safety. This was a long list for me and my surgical team went so far and to cover every substance I would come into contact with the day of my surgery and again, just before their use to ensure no mistakes were made. I found this incredibly reassuring and would love to see more surgeons employ these tactics.
On the day of the procedure, you will be asked to refrain from eating and drinking for a period of time prior to your procedure. If only a local is used, as was the case for me, you can eat up to two hours prior to your procedure. If twilight sleep or sedation is employed, you may need to discontinue foods by midnight on the night before your procedure.
Finally, you will need to be accompanied by an adult who can drive you home and stay with you for at least 24 hours after your procedure. You may be given a gown for your procedure or your clothing may be draped in order to protect it and create a sterile field.
If the procedure is to be performed on a child, parents may be allowed to accompany them during the procedure.
How a Spinal Tap is Performed
Most scheduled LPs are out patient procedures and you can usually go home within 30-60 minutes of completion. A LP is performed with the use of fluoroscopy. In fluoroscopy, an x-ray is taken and then converted into a digital image your physician can see on screen. This helps them to be very precise when placing the needle in the spinal canal, reducing the danger of injury to the spinal cord.
At the beginning of the procedure, an IV may be placed in the arm or hand to administer the sedative, if one is given. You will likely be asked to lay on your stomach and may be asked to position your arms above your head with your face to the doctor so you can easily communicate. If you have difficulty with this position due to spine issues or other disability, ask the team to help you get into a position you’re comfortable in. It is very important to be able to lay still during the procedure, so you must be comfortable.
Once in position, the patient will be draped with sterile cloth and the surgical field will be sterilized with a preparatory solution, such as Betadine. A local anesthetic will be administered, which may feel like a pinch or sting.
The x-ray is taken and appears on the fluoroscopy monitor to guide your doctor. Once she or he has located the correct spot, they will begin the insertion of the needle and may occasionally take other x-rays to determine the depth of the needle is correct. There are several layers to get through, and while you shouldn’t feel pain, you may feel the needle access each layer of tissue and feel a pop as it goes through the final layer. It’s best to keep this in mind, so you remain calm and still despite these strange sensations. According to Doherty and Forbes:
The Lumbar Puncture needle pierces in order: skin, subcutaneous tissue, supraspinous ligament, interspinous ligament, ligamentum flavum, epidural space containing the internal vertebral venous plexus, dura, arachnoid, and finally the subarachnoid space.
Consent should include the risk of Post-Lumbar Puncture Headache (PLPH), which has a published incidence of 32%. Other risks to discuss include failure to obtain CSF, localised bruising, bleeding and local discomfort at the injection site. Iatrogenic meningitis and nerve root injury are exceptionally rare.“Diagnostic Lumbar Procedure,” NBCI
This is important, not only because you can feel the needle break through some of these layers, but also because the puncture of ligaments can cause some soreness and back pain in the days following the procedure and people with collagen disorders should probably consider the need for extra healing time due to our deficiency and slow healing times.
Once the needle is inserted, you may be helped to reposition yourself to your side, taking the fetal position. The fetal position is the proper position for which spinal taps are usually performed when entering from the lumbar region of the spine.
If opening pressures are requested, as in the event of suspected CSF leak or IIH, the doctor will call out these numbers to the nurse for documentation and may or may not be commented upon. Then the appropriate amount of CSF fluid will be removed for testing.
During the procedure, you will be asked to monitor how you feel and whether or not your symptoms are changing as your fluid is collected. I didn’t feel any real difference during the procedure, however by the time I left the facility 30 minutes later, my headache was completely resolved, I was no longer light sensitive and my vision cleared as if the ward I was on had gone from dismal and dreary to full sun; a sun I could now look toward without intense pain. This indicated to the team that my pressures were indeed too high for my particular physiology. Once an adequate amount is removed for testing, the needle is removed, a band-aid is applied and you are asked to lay on your back to allow gravity to help with the work of closing the wound.
Post Procedure Expectations
Your team will likely check on you a couple of times while you recover in post-op. They will ask you questions about your symptoms and ensure everything is fine before sending you home. While it is important that you lay flat in your bed for a period after your procedure (usually 24 hours), you can simply tip the seat back in your car for the ride home.
Be sure to follow the recommendations of your care team to facilitate healing and avoid infection, which could be very serious. For this reason, it’s also very important to keep your team informed about any new symptoms or changes you experience after your procedure, both to ensure your safety should complications arise and in the event that further testing or procedures are indicated to take care of any problems which may arise.
It is important that the patient lay flat both to facilitate healing and to help avoid a spinal headache, which can happen if too much CSF is removed or continues to leak. Each day beyond the 24 hour period, you should attempt to be up and about. If no headache occurs, you’re generally free to go on about your life, with the exception of swimming and bathing (showering is okay). However if a spinal headache begins, the only solution is to lay in bed for another day. This process is repeated over the next two days. If on the 4th day you rise and experience a headache, a blood patch may be necessary.
A blood patch requires a second lumbar puncture in which your own blood is used to bring the pressure back up and to help facilitate clotting.
Barring any initial complications which might indicate the need for a blood patch, some patients may experience a spike in intracranial pressure within a few weeks after the procedure which would indicate an overproduction of CSF. In this case, another lumbar puncture will be performed to bring the pressure back down and a stent may be inserted to maintain drainage.
CSF Testing and Analysis
There are many tests that can be performed on CSF. Which tests your doctor orders depend largely on your symptoms and the outcomes of other diagnostic testing. Tests range include the observation of its physical characteristics (pressure, color, viscosity, turbidity), chemical tests to analyze the composition and content of fluid (immunoglobulins, proteins, LD, CRP and others), microscopic examination of red blood cells, white blood cells and cytology, and infectious and parasitic tests. For a complete list with detail, go here.
My CSF Analysis:
Because my doctor and I were most concerned about intracranial hypertension due to my specific symptoms, most of my tests were directed at this problem, with a few extras to rule out other possibilities. These are the tests he ran:
Rather than showing you the negative ones, I’ll include images of the surgeon’s notes, along with those which were abnormal.
This test indicates my blood-brain barrier is slightly impaired. This could explain why my “brain fog” has continued to grow, as everything that’s come up in my search on the subject points to either Alzheimer’s Disease or multi-infarct dementia (MID). I don’t find this overly surprising as my grandmother had Alzheimer’s and my mother was showing definite signs as early as 50. It seems I must beat them to every diagnosis. I will likely write more on this subject as it’s entirely too vast and somewhat off-topic, but obviously I need to explore this further.
The high protein levels in my CSF may indicate there’s brain injury (possibly due to a mild chiari malformation that hasn’t been caught on a supine MRI, but could also be a sign of a tumor, bleeding, or nerve inflammation. This needs to be explored further.
As you can see, more exploration is necessary based on my test results. It will likely be a while before I have an official diagnosis in light of these tests. My doctor started by putting me on a diuretic, which will likely interfere with my POTS and have to be withdrawn. If my pressure climb again, I may need a repeat procedure and a stent placed. Until I meet with him in mid- September, I will not know for sure if he is diagnosing me with intracranial hypertension, but it seems highly likely. At this point, he would have no choice but to label it as idiopathic since no source has yet been discovered.
For many people with EDS, the cause is often related to craniocervical instability (CCI) and/or Chiari malformation (CM), though sometimes a tear in our delicate soft tissues is indicated as the cause of a CSF Leak. Interestingly, CSF leak is often what causes Intracranial hypertension. While I have struggled with symptoms of these problems for years, I need a qualified neurosurgeon who understands and can order proper flexion and extension MRI’s to either confirm or rule out CCI or CM. As much as I love and appreciate my head pain specialist, it’s beyond his realm of expertise.
CCI, CM, CSF leaks and IIH are all topics we have yet to explore on the Zebra Pit. They are topics I plan to cover in the coming months. Of these conditions, which do you think we should cover first? Are you affected by any of these conditions? We’d love to hear your experiences with lumbar puncture and diagnosis! Let us know about it in the comments.
As always, thanks so much for joining us! I hope you found this post educational and interesting. I hope you’ll share it with others who might also find it useful.
Resources and Further Reading
- Cerebrospinal Fluid-Britannica Science
- Cerebrospinal Fluid Leak – Cedars-Sinai
- Lumbar Punctures – Radiologyinfo.org
- Diagnostic Lumbar Puncture – NCBI.org
- Epidural Blood Patch – URMC
- Neurological and Spinal Manifestations of the Ehlers-Danlos Syndromes – Ehlers-Danlos Society
- Venous Sinus Stenting in the Management of Patients with Intracranial Hypertension Manifesting with Skull Base Cerebrospinal Fluid Leaks -NCBI
- CSF Analysis – Lab Tests Online
- CSF Total Protein – Mount Sinai
- Idiopathic Intracranial Hypertension – NORD