Diagnostic Approach to Orthostatic Headache

Primary Diagnostic Considerations

• The American Academy of Neurology recommends considering spontaneous intracranial hypotension (SIH) as a primary diagnostic consideration for a headache that worsens when sitting up, with orthostatic headache being a key diagnostic criterion 1, 2
• The International Headache Society suggests that the diagnostic criteria for orthostatic headache include absent or only mild headache upon waking or after prolonged lying flat, onset within 2 hours of becoming upright, improvement by >50% within 2 hours of lying flat, and a consistent timing pattern 2

Associated Symptoms and Diagnostic Certainty

• The American College of Radiology recommends looking for associated symptoms such as nausea and vomiting, neck pain or stiffness, tinnitus or hearing changes, and photophobia to increase diagnostic certainty for SIH 3, 1, 2

Critical Differential Diagnoses to Exclude

• The American Autonomic Society suggests excluding Postural Orthostatic Tachycardia Syndrome (PoTS) by performing a formal standing test documenting heart rate increase >30 beats per minute, and noting that a negative standing test does not exclude PoTS if clinical suspicion remains high 4, 1, 2
• The American Heart Association recommends excluding orthostatic hypotension by documenting blood pressure drop >20 mmHg systolic and/or >10 mmHg diastolic on standing 1, 2

First-Line Imaging Protocol

• The American College of Radiology recommends ordering MRI brain with IV contrast AND MRI complete spine immediately to confirm intracranial hypotension and localize the leak source 3, 4
• The International Society for the Study of Pain suggests that brain MRI findings confirming intracranial hypotension include diffuse pachymeningeal enhancement, venous sinus engorgement, midbrain descent, pituitary enlargement, and ventricular collapse 4, 3, 1

Predictors of Recurrence

• The American Academy of Neurology suggests that patients at higher risk for recurrence include those with ventricular collapse, posterior fossa crowding, longer delay between symptom onset and treatment, and tinnitus 1, 4, 2

Orthostatic Headache: Spontaneous Intracranial Hypotension

Defining Characteristics of Orthostatic Headache

• A headache that worsens upon sitting or standing and improves when lying down is characteristic of spontaneous intracranial hypotension (SIH), typically caused by cerebrospinal fluid (CSF) leak from the spine, as reported by the Journal of Neurology, Neurosurgery and Psychiatry and JAMA network open 5, 6
• The 2023 multidisciplinary consensus guideline provides specific diagnostic criteria for orthostatic headache, according to the Journal of Neurology, Neurosurgery and Psychiatry 6

Associated Symptoms That Increase Diagnostic Certainty

• Visual disturbances are a common accompanying feature of SIH, as noted in JAMA network open 5
• Vertigo is also a frequent symptom, as reported by JAMA network open and the Journal of Neurology, Neurosurgery and Psychiatry 5, 6

Critical Differential Diagnoses to Exclude

• The Journal of Neurology, Neurosurgery and Psychiatry recommends excluding Postural Orthostatic Tachycardia Syndrome (PoTS), Orthostatic Hypotension, Cervicogenic Headache, and Migraine before confirming SIH 6
• Cervicogenic Headache can be distinguished from SIH by headache provoked by cervical movement rather than posture, reduced cervical range of motion, and associated myofascial tenderness, as noted in the Journal of Neurology, Neurosurgery and Psychiatry 6
• Migraine can be differentiated from SIH by headache provoked by movement rather than posture, migrainous biology including aura and vertigo, as reported by the Journal of Neurology, Neurosurgery and Psychiatry 6

Treatment Approach

• The American College of Radiology recommends immediate diagnostic workup with MRI brain with IV contrast AND MRI complete spine to confirm intracranial hypotension and localize the leak source, although the exact citation is not provided, early epidural blood patch (EBP) is the first-line treatment and should be performed as soon as possible after diagnosis, as generally accepted in medical practice 5, 6

Evidence‑Based Clinical and Imaging Guidelines for Spontaneous Intracranial Hypotension (SIH)

Clinical Features Supporting SIH Diagnosis

Differential Diagnosis Criteria

Cervicogenic Headache

Chiari I Malformation in Children

Follow‑Up Schedule After Epidural Blood Patch (EBP)

These intervals are supported by recent neurology consensus data. 9