September 20, 2022 - Written By: Maria Arini Lopez, PT, DPT
Many factors cause headaches, including, but not limited to:
tension in the neck muscles
abnormal nerve activity in the brain affecting nerve signaling, chemicals, and blood flow within the brain (migraines), and
changes in the amount of fluid (known as cerebrospinal fluid or CSF) surrounding and protecting the brain.
CSF surrounds the brain and spinal cord and is contained within the meninges. The meninges are three layers of membranes that cover and protect the brain and spinal cord.
When the amount of CSF is lower or higher than normal, this may cause a low-pressure or a high-pressure headache, respectively. In medical lingo, low-pressure headaches may be called spontaneous intracranial hypotension (SIH), while high-pressure headaches may be referred to as idiopathic intracranial hypertension (IIH). This blog will focus on low-pressure headaches and the next one will focus on high-pressure headaches.
Low-pressure Headaches
Low-pressure headaches are caused by lower amounts of CSF surrounding the brain and keeping the brain floating within the skull. They worsen in upright positions (sitting or standing) and may improve when lying down. The pain from these headaches may not be present early in the morning, but symptoms may worsen after rising from bed.
Symptoms
Headache pain typically is worse in the back of the head. This occurs when the brain is displaced downward in the upright position due to decreased CSF levels supporting it. Accompanying symptoms may include nausea, vomiting, visual disturbances, neck pain and/or stiffness, dizziness/vertigo, altered hearing, and pain in between the shoulder blades. Other, more severe neurological symptoms rarely present if the brain is displaced downward, stretching the nerves and meningeal layers.
Causes
The most common cause of a low-pressure headache is a cerebrospinal fluid (CSF) leak. Common causes of CSF leaks include spinal surgeries, lumbar punctures, or trauma to the head or neck.
Coughing, sneezing, and physical exertion like lifting heavy objects also may cause CSF leaks because these actions increase the pressure within the CSF and may push outward against the meninges and cause a rupture in a weakened area of the membranes. Sneezing, coughing, and exertion may also aggravate the pain throughout the head.
Sometimes, CSF leaks occur spontaneously or without known cause. These types of CSF leaks often are underdiagnosed or misdiagnosed. Some studies show that people with hereditary connective tissue disorders such as Ehlers Danlos Syndrome and Marfan Syndrome have a predisposition for developing spontaneous CSF leaks due to the inherent weakness of the connective tissues including the spinal dura mater (the outermost layer of the meninges). It is possible that increased laxity of the spinal ligaments allows for hypermobility of the spinal vertebrae which may in turn add mechanical stress on the dura, increasing the risk of spontaneous tears.
Another study reported a connection between spinal fractures and spinal CSF leaks.
Diagnosis
Sometimes, doctors can find the location of the CSF leak on imaging such as magnetic resonance imaging (MRI) scans or computed tomography (CT) scans, but sometimes the location of the leak may not be apparent. Another way that doctors can diagnose low pressure of the CSF is through a lumbar puncture, which, ironically, is also a cause of CSF leaks.
Treatment Options
One way to treat these low-pressure headaches caused by CSF leaks is called an epidural blood patch. Doctors collect blood from a vein in the arm of a patient who is experiencing low-pressure headaches and injects this blood just above the meninges (epidural). This may help close or patch up the leak, but it may not work the first time, requiring several repetitions of the procedure to relieve symptoms.
Another option that doctors may prescribe is a medication called theophylline that is injected into the veins. Theophylline causes the veins in the brain to constrict which may help alleviate the painful symptoms of a low-pressure headache.
Bottom Line
People who have been diagnosed with a connective tissue disorder should have careful discussions with their doctor about getting a lumbar puncture for diagnostic purposes. If this procedure is absolutely necessary, having an epidural blood patch immediately after the lumbar puncture might help ward off these low-pressure spinal headaches, especially if you have a history of CSF leaks.
People who have experienced low-pressure headaches, especially without known cause, might want to ask their doctor about getting evaluated for a connective tissue disorder.
References and Resources
Donovan J. Low-Pressure and High-Pressure Headaches. WebMD. Accessed September 9, 2022.
Low CSF Headache. Johns Hopkins Medicine. Accessed September 9, 2022.
Petkovic G, Rose-Innes E, Bojanic S, Leite MI, Wakerley BR. High and low pressure headaches: a spinal cause. Practical Neurology. 2018;18(5):413-414. doi:10.1136/practneurol-2017-001769
Reinstein E, Pariani M, Bannykh S, Rimoin DL, Schievink WI. Connective tissue spectrum abnormalities associated with spontaneous cerebrospinal fluid leaks: a prospective study. Eur J Hum Genet. 2013;21(4):386-390. doi:10.1038/ejhg.2012.191
Schievink WI. Spontaneous Spinal Cerebrospinal Fluid Leaks and Intracranial Hypotension. JAMA. 2006;295(19):2286-2296. doi:10.1001/jama.295.19.2286
Lay CM. Low Cerebrospinal Fluid Pressure Headache. Curr Treat Options Neurol. 2002;4(5):357-363. doi:10.1007/s11940-002-0046-9
Chan TLH, Cowan R, Hindiyeh N, Hashmi S, Lanzman B, Carroll I. Spinal cerebrospinal fluid leak in the context of pars interarticularis fracture. BMC Neurology. 2020;20(1):162. doi:10.1186/s12883-020-01740-1
Akdere H, Burgazli KM. The Efficiency of Intravenous Theophylline on the Headache Which Occurs After Spinal Anesthesia. Journal of Neurology Research. 2011;1(5):190-192. doi:10.4021/jnr.v1i5.78
Maria Arini Lopez, PT, DPT
Maria Arini Lopez, PT, DPT, CSCS, CIMT, CMTPT is a freelance medical writer and Doctor of Physical Therapy from Maryland. She has expertise in the therapeutic areas of orthopedics, neurology, chronic pain, gastrointestinal dysfunctions, and rare diseases, especially Ehlers Danlos Syndrome.