Low pressure headaches caused by spontaneous intracranial hypotensionBMJ 2014; 349 doi: https://doi.org/10.1136/bmj.g6219 (Published 05 November 2014) Cite this as: BMJ 2014;349:g6219
- Shona Scott, neurology registrar,
- Richard Davenport, consultant neurologist
- 1Department of Clinical Neurosciences, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
- Correspondence to: R Davenport
The bottom line
Ask all patients with a new headache: “Is your headache made worse by changing posture from lying down to an upright position? Prominent postural features (pain worse when upright) should alert clinicians to the possible diagnosis of spontaneous intracranial hypotension
If spontaneous intracranial hypotension is suspected and the patient is debilitated, magnetic resonance imaging of the head with gadolinium is the best investigation. It typically shows pachymeningeal enhancement, and features of brain “sagging” may also be seen on sagittal views
Imaging evidence of subdural collections or brain sagging should trigger a review of the history in patients with headache if spontaneous intracranial hypotension has not previously been considered
If conservative management is unsuccessful, epidural blood patch may relieve the headache
How patients were involved in the creation of this article
A patient recently diagnosed with spontaneous intracranial hypotension who also underwent a blood patch for the management of her condition wrote the patient perspective and gave permission for the magnetic resonance imaging scans to be included. Her comments on the draft manuscript have been incorporated in the revised paper. In particular, she highlighted that she was initially diagnosed with migraine and her postural symptoms were not appreciated. She wishes to raise awareness of the condition and its management.
What is spontaneous intracranial hypotension?
Low pressure headaches are caused by low cerebral spinal fluid (CSF) pressure or volume, and they may be spontaneous or provoked (for example, after lumbar puncture, inadvertent dural puncture during spinal anaesthesia, or neurosurgical procedures). Low pressure headache without apparent provocation is termed spontaneous intracranial hypotension (SIH). Such headaches are typically postural—they are eased by lying down but worsened in the upright position, which may result in patients being bed bound. The postural nature is assumed to be due to loss of CSF through a breach in the dura mater. This results in gravitational downward displacement of the brain and causes traction …