What is Postdural Puncture Headache (Lumbar Puncture Headache)?
Postdural puncture headache (PDPH) is a possible side effect that might occur after a lumbar puncture, which is a procedure where a needle is used to extract fluid from the spine. The symptoms of PDPH are often caused by low pressure in the brain due to a cerebrospinal fluid (CSF) leak at the site where the puncture was made. This low pressure can pull on structures within the brain that are sensitive to pain, causing a headache.
What Causes Postdural Puncture Headache (Lumbar Puncture Headache)?
PDPH, or post-dural puncture headaches, can be caused by a variety of things. These include procedures like a lumbar puncture, diagnostic myelography, a spinal block, or an accidental puncture from epidural anesthesia or pain injection. Similar symptoms, caused by low cerebrospinal fluid pressure, can also occur on their own or after brain surgery, placement of ventricular shunts, brain/spinal trauma, or spinal surgery.
Several risk factors can increase the chances of getting PDPH. These include being dehydrated, having an illness, a history of headaches, using a large needle during procedures, being female, being pregnant, being young, using a large or cutting spinal needle, or having a procedure done by a less experienced professional.
Risk Factors and Frequency for Postdural Puncture Headache (Lumbar Puncture Headache)
PDPH, or Post-Dural Puncture Headaches, are more common in women, younger people (20-40 years old), those who are thinner, and those who have experienced headaches in the past, particularly PDPH. It’s less common in older people, potentially due to brain shrinkage with age.
- Various factors can increase the risk of PDPH, such as the size of the needle used, using a cutting needle, especially if it’s inserted or rotated at a right angle to the dural fibers (tissue layers surrounding the brain and spinal cord).
- On the other hand, using a smaller needle with a pencil-like tip, or reinserting the needle’s inner part can reduce the risk.
- Interestingly, the doctor’s experience, the number of needle insertions, and the removal of large amounts of CSF (cerebrospinal fluid) may or may not influence PDPH occurrence.
- The patient’s position during or after the procedure doesn’t seem to affect the chances of getting PDPH.
The estimated incidence of PDPH is between 10% and 40% of all lumbar puncture procedures. However, using smaller, non-cutting needles can lower this rate to as little as 2%. Symptoms of PDPH usually show up within 48 to 72 hours after the procedure but can sometimes be delayed for months.
Signs and Symptoms of Postdural Puncture Headache (Lumbar Puncture Headache)
PDPH, or post-dural puncture headache, is characterized by symptoms such as a headache that mainly occurs on both sides of the forehead or at the back of the head and becomes worse in an upright position but gets better when lying down. The headache may be associated with feelings of nausea, dizziness, pain in the neck, changes in vision, and in some cases, ringing in the ear, hearing loss or sensations radiating into the arms. Also, the headache can get worse with coughing and while straining, even when lying down.
Usually, a physical examination does not show any remarkable findings, and the person should not have fever, stiff neck, altered mental state, or specific neurological symptoms. However, in rare cases, there might be unusual signs like uncontrolled eye movements, double vision, numbness or weakness in the face. It’s uncommon, but a weakness in cranial nerve VI (Abducens) may cause double vision. A constant firm pressure in the abdomen might temporarily improve the headache symptoms because it indirectly boosts the pressure of the cerebrospinal fluid. However, applying pressure on the jugular vein can make the headache symptoms worse.
Testing for Postdural Puncture Headache (Lumbar Puncture Headache)
Post-dural puncture headaches (PDPH) are usually diagnosed based on symptoms, so lab tests or imaging are not typically needed. However, if the headache is severe or doesn’t get better with lying down, an imaging scan may be done to rule out other serious conditions.
Lumbar puncture, which is a procedure to collect fluid from around the brain and spinal cord, is usually not recommended for patients suspected of having PDPH as it could worsen the symptoms. But if the procedure is done, the fluid might show a low pressure reading and could contain white and red blood cells, or higher protein levels. The fluid may also appear yellowish.
For patients with PDPH that lasts a long time or those with intracranial hypotension (a condition where the brain loses support from the spinal fluid), an MRI scan might show several changes in the brain. This includes downward displacement of the cerebellar tonsils (a condition that also happens in a disorder called Chiari type 1), thinning of the spaces filled with cerebrospinal fluid at the base of the brain, thickening of the layers covering the brain, fluid accumulation, swelling of the veins, and an enlarged pituitary gland. All these changes can be reversed with treatment.
Also, a CT scan of the brain may show thinning of the cerebrospinal fluid spaces at the base of the brain. This might be confused with a form of stroke called subarachnoid hemorrhage. For identifying the location and extent of cerebrospinal fluid leak, a CT myelography or an MRI of the spine can be used.
Treatment Options for Postdural Puncture Headache (Lumbar Puncture Headache)
If you have a Post-Dural Puncture Headache (PDPH), initial treatment often consists of taking simple painkillers, drinking fluids, and avoiding standing up. In more than two-thirds of patients, these headaches resolve on their own within one to two weeks. However, in many cases, the symptoms can be very severe and not go away, necessitating further treatment.
There is some evidence suggesting that drinking or being given caffeine through an IV drip (300 mg to 500 mg in a liter of fluid over an hour) can ease PDPH. However, it’s important to note that the relief offered by caffeine may only be temporary, and the headache can come back.
In some cases, the leak in the dura (the outermost layer protecting the brain) causing the headache gets better on its own within a few days to weeks, so no there’s no need for specific treatment. That said, if the symptoms continue for a long time and no treatment is given, it may lead to complications.
A method of using blood to cover the hole in the dura was introduced in 1960 by Dr. James Gorley, a surgeon from Pennsylvania. This soon became the concept for the ‘epidural blood patch’.
When symptoms continue even after simple treatments, the next step is often towards an epidural blood patch. This is particularly true for new mothers who need to take care of their child and find PDPH highly debilitating. During this procedure, a doctor injects 10 ml to 30 ml of the patient’s own blood into the space surrounding the dura. This is thought to “patch up” the puncture and reduce the leakage of cerebrospinal fluid or simply increase the pressure inside the skull. This treatment has proven successful in majority of the cases. However, it can occasionally cause back pain, irritation of the meninges (the protective layers around the brain), nerve root irritation, bulbar neuropathy, infection of the meninges, hematoma or cauda equina syndrome (a condition affecting the nerves at the end of the spinal cord).
A two to three-day continuous saline drip into the epidural space may be less effective than a blood patch and also have fewer side effects. This treatment requires a catheter in the epidural space, bedrest and a hospital stay, so it is rarely used.
Some experimental treatments include oral or injected steroids, ACTH injections into the muscle, oral gabapentin, methylxanthines like IV aminophylline or oral theophylline. Some studies have also suggested using local injections of glues like cyanoacrylate or fibrin for cases that do not respond to other treatments. That said, due to the high success and low complication rates, the epidural blood patch is considered the gold standard of treatment for PDPH.
Some studies suggest that taking Frovatriptan for 5 days before a lumbar puncture can reduce the chance of developing headaches after the procedure. However, Sumatriptan did not show the same benefit when used for just 1 day before the procedure.
What else can Postdural Puncture Headache (Lumbar Puncture Headache) be?
When dealing with certain health conditions, it’s essential to consider various possibilities that could be causing them. These include:
- Withdrawal from caffeine
- Conditions related to the brain structure (intracranial pathology)
- Meningitis (an infection of the membranes around the brain and spinal cord)
- Migraines (severe, recurring headaches)
- Pneumocephalus (air or gas within the cranial cavity)
- Health problems related to the sinuses
- Preeclampsia (a pregnancy complication characterized by high blood pressure)
It’s important for your healthcare provider to take these into account to accurately diagnose and manage your condition.
Possible Complications When Diagnosed with Postdural Puncture Headache (Lumbar Puncture Headache)
In rare cases, if the condition becomes severe or lasts a long time, it can lead to some serious complications. These can include:
- A condition called cerebral venous thrombosis where blood clots form in the brain’s venous sinuses.
- Subdural hematoma, which is bleeding on the brain caused by stretched veins.
- Seizures or uncontrollable shaking.
- Hypopituitarism, or a deficiency in pituitary hormone.
- Syringomyelia, a rare disorder in which a cyst or cavity forms within the spinal cord.
- Herniation, which is the displacement of an organ or tissue.
- Coma, a state of unconsciousness lasting more than six hours.
- In extreme cases, these complications can be fatal.
Preventing Postdural Puncture Headache (Lumbar Puncture Headache)
The best way to prevent a condition called Post-Dural Puncture Headache (PDPH) is by using a thin, pencil-like spinal needle that doesn’t cut. There’s no solid proof to show that extra fluid intake or bed rest after the procedure can actually prevent PDPH. Injecting medications like aminophylline, a hormone called adrenocorticotrophic (ACTH), or a painkiller like epidural morphine into a vein may help reduce the chance of getting PDPH. However, we need more research to fully understand how effective these treatments are.
