Assessment of CSF flow dynamics using PC-MRI in spontaneous intracranial hypotension

Spontaneous intracranial hypotension (SIH) is caused by spontaneous cerebrospinal fluid (CSF) leaks and is known to cause orthostatic headaches. Phase-contrast magnetic resonance imaging (PC-MRI) is a non-invasive technique that can be used to quantify variation in CSF flow. The aim of this study was to assess CSF flow dynamics using PC-MRI in SIH.

Twenty-five patients with a definitive diagnosis of SIH and 25 healthy subjects were evaluated with PC-MRI. Magnetic resonance (MR) images were acquired using a 1.5-T unit with an 8-channel head coil. Differences between SIH patients and control subjects were assessed statistically using Wilcoxon's rank sum test, Spearman's rho test, or Pearson's chi-square test, as appropriate.

CSF flow volumes toward the third ventricle, CSF flow volumes toward the fourth ventricle, the absolute stroke volume, the peak systolic velocity, and the peak diastolic velocity in SIH patients were significantly smaller than those in control subjects (P < .0001). On the other hand, the net CSF flow volume (P = .9227) and the net CSF flow direction (P = .2472) for SIH patients and control subjects were not significantly different.

The results obtained by CSF flow analysis were directly related to values of CSF opening pressure, determined by lumbar puncture, and clinical findings, such as headache scores. Thus, CSF flow analysis with PC-MRI, which has a short performance time and is non-invasive, may contribute to assessment of SIH patients.