Spinal Cerebrospinal Fluid Leak
– An Under-recognized Cause of Headache
Spontaneous leaks may occur at any age and
in both genders but are diagnosed more often in
women around age 40. An estimated incidence of
5 in 100,000 per year is based on a single study of
patients presenting to an emergency department and
is probably an underestimate since most patients are
now diagnosed on an outpatient basis.
Medical Procedures
The most common cause of a spinal CSF leak is
a lumbar puncture (spinal tap), in which the spinal
dura is intentionally punctured for diagnostic or
therapeutic reasons. A positional headache that
develops after the procedure is usually recognized and
treated promptly.
Underlying Causes
Spontaneous
The cases that occur with no apparent precipitating
event or a relatively minor physical factor, such
as lifting or bending, are the type that most often
remain unrecognized for months or years. There are
two known associations with spontaneous spinal CSF
leaks. Patients may have an underlying weakness of the
spinal dura from an inherited disorder of connective
tissue, including but not limited to Ehlers-Danlos
syndromes and Marfan syndrome. The second
known association is underlying bone spurs arising
from calcified intervertebral (between the vertebrae)
discs. These bone spurs can puncture the spinal dura.
Another well-known cause of a spinal CSF leak is
an inadvertent puncture of the spinal dura during an
epidural anesthesia or an epidural steroid injection.
These injections normally go into the space inside the
spinal canal but outside the dura.
Spinal surgery can be complicated by nicks or tears
of the spinal dura. These leaks may or may not be
recognized promptly.
Over-draining CSF shunts are also known to cause
intracranial hypotension.
Trauma
Cerebrospinal fluid leaks have been reported in
association with injuries sustained in falls, motor
vehicle accidents, or sports injuries.
W
Spontaneous intracranial hypotension, or low cerebrospinal fluid (CSF)
pressure inside the head, is an under-recognized cause of headache
that is both treatable and in many cases, curable.
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HeadW ise ®
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Volume 7, Issue 1 • 2018