7.2.3 Headache attributed to spontaneous intracranial hypotension

Previously used terms:

Headache attributed to spontaneous low CSF pressure or primary intracranial hypotension; low CSF-volume headache; hypoliquorrhoeic headache.

Description:

Orthostatic headache caused by low cerebrospinal fluid (CSF) pressure of spontaneous origin. It is usually accompanied by neck stiffness and subjective hearing symptoms. It remits after normalization of CSF pressure.

Diagnostic criteria:
  1. Headache fulfilling criteria for 7.2 Headache attributed to low cerebrospinal fluid (CSF) pressure, and criterion C below
  2. Absence of a procedure or trauma known to be able to cause CSF leakage1
  3. Headache has developed in temporal relation to occurrence of low CSF pressure or CSF leakage, or has led to its discovery2
  4. Not better accounted for by another ICHD-3 diagnosis.
Notes:
  1. 7.2.3 Headache attributed to spontaneous intracranial hypotension cannot be diagnosed in a patient who has had a dural puncture within the prior month.
  2. Dural puncture to measure CSF pressure directly is not necessary in patients with positive MRI signs of leakage such as dural enhancement with contrast.
Comments:

Spontaneous cerebrospinal fluid (CSF) leak has been associated with heritable connective tissue disorders. Patients with CSF leaks should be screened for connective tissue and vascular abnormalities.

While there is a clear postural component in most cases of 7.2.3 Headache attributed to spontaneous intracranial hypotension, it may not be as dramatic or immediate as in 7.2.1 Post-dural puncture headache. Thus, 7.2.3 Headache attributed to spontaneous intracranial hypotension may occur immediately or within seconds of assuming an upright position and resolve quickly (within 1 minute) after lying horizontally, resembling 7.2.1 Post-dural puncture headache, or it may show delayed response to postural change, worsening after minutes or hours of being upright and improving, but not necessarily resolving, after minutes or hours of being horizontal. The orthostatic nature of the headache at its onset should be sought when eliciting a history, as this feature may become much less obvious over time.

In patients with typical orthostatic headache and no apparent cause, and after exclusion of postural orthostatic tachycardia syndrome (POTS), it is reasonable in clinical practice to provide autologous lumbar epidural blood patch (EBP). While EBPs are frequently effective in sealing CSF leaks, the response to a single EBP may not be permanent, and complete relief of symptoms may not be achieved until two or more EBPs have been performed. However, some degree of sustained improvement, beyond a few days, is generally expected. In some cases, sustained improvement cannot be achieved with targeted (to the site of the leak) and/or non-targeted lumbar EBPs, and surgical intervention may be required.

It is not clear that all patients with 7.2.3 Headache attributed to spontaneous intracranial hypotension have an active CSF leak, despite a compelling history or brain imaging signs compatible with CSF leakage. The underlying disorder may be low CSF volume. A history of a trivial increase in intracranial pressure (eg, on vigorous coughing) is sometimes elicited.

Postural headache has been reported after coitus: such headache should be coded as 7.2.3 Headache attributed to spontaneous intracranial hypotension because it is most probably due to CSF leakage.