7.1.2 Headache attributed to intracranial hypertension secondary to metabolic, toxic or hormonal causes

Coded elsewhere:
Headache attributed to increased intracranial pressure due to head trauma, vascular disorder or intracranial infection is coded to whichever of these is the cause. Headache attributed to raised intracranial pressure occurring as a side-effect of medication is coded as 8.1.11 Headache attributed to long-term use of non-headache medication.

Description:
Headache caused by intracranial hypertension secondary to a variety of systemic disorders and accompanied by other symptoms and/or clinical signs of intranial hypertension. It remits with resolution of the systemic disorder.

Diagnostic criteria:
A. Any headache fulfilling criterion C
B. A metabolic, toxic or hormonal disorder has been diagnosed, with CSF pressure >250 mm CSF (measured by lumbar puncture performed in the lateral decubitus position, without sedative medications or by epidural or intraventricular monitoring) and with normal CSF chemistry and cellularity
C. Evidence of causation demonstrated by either or both of the following:

    1. headache has developed in temporal relation to the metabolic, toxic or hormonal disorder
    2. either or both of the following:

      a) headache has significantly worsened in parallel with worsening of the metabolic, toxic or hormonal disorder
      b) headache has significantly improved in parallel with improvement in the metabolic, toxic or hormonal disorder

D. Not better accounted for by another ICHD-3 diagnosis.

Comments:
Potential causes of intracranial hypertension include acute hepatic failure, hypercarbia, acute hypertensive crisis, Reye’s hepatocerebral syndrome and heart failure.

Removal of the inciting agent or treatment of the secondary cause may not be sufficient to normalize the high intracranial pressure; additional treatment is often required to prevent visual loss, and to relieve headache and other symptoms.