When to Suspect a CSF Leak in Patients With Headache

Causes of Leaks

The four main causes of CSF leaks are medical procedures; whiplash; bony, sharp calcifications penetrating the dura; and genetic disorders of connective tissue.

Webb et al conducted a study to evaluate headaches in patients who had a known wet tap (ie, unintentional dural puncture) after a labor epidural. The researchers reviewed quality assurance data in an obstetrics anesthesia division and identified 40 patients who had known wet taps and 40 controls who had received an epidural without a wet tap during the same week and were matched for age and weight. Investigators contacted patients between 12 and 24 months later (mean, 18 months) and asked them about the incidence of chronic headache. The incidence of chronic headache in controls was 5% versus nearly 30% in patients who had had a wet tap. The investigators then compared patients who were managed conservatively (ie, they did not receive an epidural blood patch) versus patients who were managed with a blood patch. “If you got a blood patch, your risk of having a chronic headache 18 months later was only half as much as if you did not get a blood patch,” he said.

Connective Tissue Disorders and Calcifications

Because connective tissue disorders are associated with CSF leaks, headache physicians should determine patients’ Beighton Hypermobility Scores, Dr. Carroll said. The score is derived from a simple test that assesses joint hypermobility. For instance, patients receive a point if they can touch their thumb to their wrist or straighten their elbow more than 10° beyond 180°. A score between 3 and 5 raises suspicion that the patient might have a hereditary disorder of connective tissue. Cataracts at an early age, being unusually tall or short, degenerative disc disease, and history of aneurysm also are associated with an increased risk of CSF leaks.

With regard to calcifications, Dr. Carroll described a patient whose main complaint was confusion upon standing too long. The patient also had neck pain. They determined that he had a calcified bone spur that was puncturing the spinal cord, causing a leak.

Whiplash

Trauma and whiplash can cause leaks. Researchers in Japan studied 66 patients with chronic whiplash-associated disorders (ie, they had a whiplash accident and complained of neck and head pain, as well as difficulty with fatigue or memory). The patients were given a radionuclide cisternogram. Thirty-seven of the 66 patients had imaging that was positive for a CSF leak. “After being patched, roughly half the people who were found to have a leak went back to work, whereas they had not been working before,” he said. Another study found that 10% of people with brachial plexus injuries have spinal fluid leaks.

Overlap With POTS

The fact that Ehlers-Danlos also is associated with postural orthostatic tachycardia syndrome (POTS) raises the possibility that patients with CSF leaks may be misdiagnosed as having POTS.

“Why should a hereditary disorder of connective tissue be associated with the only two known conditions that are associated with feeling worse when you are up?” Dr. Carroll asked. Among patients with POTS, 60% have headaches, and many have dizziness and nausea. Dr. Carroll asked the POTS clinics at Stanford to refer patients with POTS, headache, and Ehlers-Danlos syndrome to him. The first referred patient’s history was consistent with a CSF leak. She had been passing out and had severe headaches for more than 10 years. Although her initial imaging was read as negative for CSF leaks, and an MRI showed no signs of intracranial hypotension, “when we patched her, in fact, she got better.” Subsequently, more patients diagnosed with POTS have been referred to the CSF leak program.

Patients initially may be diagnosed as having chronic fatigue syndrome, fibromyalgia, or irritable bowel syndrome when a CSF leak is causing their symptoms. It is a tragedy when patients “have a fixable leak and … nothing is done to treat that underlying problem,” Dr. Carroll said.

—Jake Remaly

Suggested Reading

Ishikawa S, Yokoyama M, Mizobuchi S, et al. Epidural blood patch therapy for chronic whiplash-associated disorder. Anesth Analg. 2007;105(3):809-814.

Schievink WI. Spontaneous spinal cerebrospinal fluid leaks and intracranial hypotension. JAMA. 2006;295(19):2286-2296.

Schievink WI, Maya MM, Moser F, et al. Frequency of spontaneous intracranial hypotension in the emergency department. J Headache Pain. 2007;8(6):325-328.

Webb CA, Weyker PD, Zhang L, et al. Unintentional dural puncture with a Tuohy needle increases risk of chronic headache. Anesth Analg. 2012;115(1):124-132.