Insights into the natural history of spontaneous intracranial hypotension from infusion testing

Abstract

ObjectiveTo assess the pathophysiologic changes in patients with spontaneous intracranial hypotension (SIH) based on measures of CSF dynamics, and on the duration of symptoms, in a retrospective case-controlled study.MethodsWe included consecutive patients investigated for SIH at our department from January 2012 to February 2018. CSF leak was considered confirmed if extrathecal contrast spillage was seen on imaging (CT or MRI) after intrathecal contrast application, or dural breach was detected by direct intraoperative visualization. We divided patients with a confirmed CSF leak into 3 groups depending on the symptom duration, as follows: ≤10, 11–52, and >52 weeks. Clinical characteristics and measures of CSF fluid dynamics obtained by computerized lumbar infusion testing were analyzed over time and compared with a reference population.ResultsAmong the 137 patients included, 69 had a confirmed CSF leak. Whereas 93.1% with <10 weeks of symptoms displayed typical orthostatic headache, only 62.5% with >10 weeks of symptoms did (p = 0.004). Analysis of infusion tests revealed differences between groups with different symptom duration for CSF outflow resistance (p < 0.001), lumbar baseline pressure (p = 0.013), lumbar plateau pressure (p < 0.001), baseline pressure amplitude (p = 0.021), plateau pressure amplitude (p = 0.001), pressure–volume index (p = 0.001), elastance (p < 0.001), and CSF production rate (p = 0.001). Compared to the reference population, only patients with acute symptoms showed a significantly altered CSF dynamics profile.ConclusionA CSF leak dramatically alters CSF dynamics acutely, but the pattern changes over time. There is an association between the clinical presentation and changes in CSF dynamics.

Monro-Kellie Hypothesis: Increase of Ventricular CSF Volume after Surgical Closure of a Spinal Dural Leak in Patients with Spontaneous Intracranial Hypotension

“…Although there is 1 report that speculates that increased CSF production in the early phase of SIH may occur, this mechanism may not be adequate. 24 Second, the intracranial blood volume, which averages $100-130 mL ($15% arterial, $40% venous, and $45% in the microcirculation), may increase. 9 The venous structures usually become enlarged and more conspicuous on imaging, leading to sinus distension, pachymeningeal enhancement, or pituitary hyperemia.…”

Spontaneous spinal cerebrospinal fluid‐venous fistulas in patients with orthostatic headaches and normal conventional brain and spine imaging

“…[1][2][3] Although a wide variety of associated symptoms has been reported, the prototypical manifestation of SIH is an orthostatic headache, especially early on in the disease process. 4 When the characteristic brain magnetic resonance imaging (MRI) findings of SIH are found in a patient who presents with orthostatic headaches, the diagnosis can be made with confidence. However, a normal brain MRI does not exclude the diagnosis of SIH.…”

Spontaneous intracranial hypotension: diagnostic and therapeutic workup

“…As lumbar puncture is invasive and only one-third of SIH patients has a CSF opening pressure < 60 mm H 2 O, MRI of the head and the spine is mandatory [15]. Note that particularly in patients with a long history of SIH or with large abdominal girth CSF opening pressure is often normal or even elevated [15][16][17].…”