Spontaneous Intracranial Hypotension : Recommendations for Management

Spontaneous intracranial hypotension (SIH) is a syndrome in which a cerebrospinal fluid leak occurs within the spinal axis, and may lead to a constellation of neurological symptoms. A postural or orthostatic headache is the most common of these symptoms1. Spontaneous intracranial hypotension was first recognized by Georg Schaltenbrand in the 1930s. Many terms have been used to describe the condition: low pressure headache, intracranial hypotension, and cerebral spinal fluid (CSF) hypovolemia. The International Classification of Headache Disorders uses “Headache attributed to spontaneous (or idiopathic) low CSF pressure”2. However, because most cases are secondary to a spontaneous spinal CSF leak, the term spontaneous spinal CSF leak or spontaneous intracranial hypotension is preferred1,3. None of these terms are completely satisfactory, however. Not all cases show a low CSF pressure on lumbar puncture, and not all of the CSF leaks are spontaneous as trauma may play a role in some cases. “Headache attributed to CSF leak” might be the best term, with cases subdivided into spontaneous and posttraumatic cases. The term “SIH” will be used here as most cases likely do have some degree of relative intracranial hypotension even though their CSF pressure may be within normal limits when measured during a lumbar puncture. Intracranial ABSTRACT: A literature search found no clinical trials or guidelines addressing the management of spontaneous intracranial hypotension (SIH). Based on the available literature and expert opinion, we have developed recommendations for the diagnosis and management of SIH. For typical cases, we recommend brain magnetic resonance (MR) imaging with gadolinium to confirm the diagnosis, and conservative measures for up to two weeks. If the patient remains symptomatic, up to three non-directed lumbar epidural blood patches (EBPs) should be considered. If these are unsuccessful, non-invasive MR myelography, radionuclide cisternography, MR myelography with intrathecal gadolinium, or computed tomography with myelography should be used to localize the leak. If the leak is localized, directed EPBs should be considered, followed by fibrin sealant or neurosurgery if necessary. Clinically atypical cases with normal brain MR imaging should be investigated to localize the leak. Directed EBPs can be used if the leak is localized; non-directed EBPs should be used only if there are indirect signs of SIH.