Abstract
BACKGROUND: The parasagittal dura (PSD) has been hypothesized to act as a neuro-immunological hub, though evidence in favor of the hypothesis is limited. The present study explored whether there is any association between volume and function of PSD and blood markers that may be indicative of systemic inflammation. METHODS: The patient material included 76 subjects examined with intrathecal contrast-enhanced magnetic resonance imaging (MRI) where the contrast served as a cerebrospinal fluid (CSF) tracer. They were dichotomized into a control- (Ctrl) and a CSF-group. We investigated the correlations between blood markers indicative of systemic inflammation and the volume of PSD, enrichment of tracer in the PSD, and blood-measures of CSF clearance. The blood markers included C-reactive protein (CRP), erythrocyte volume fraction (EVF), hemoglobin (Hb), platelet count, neutrophiles, lymphocytes, and the neutrophil-to-lymphocyte ratio as well as the platelet-to-lymphocyte ratio. Assessment of subjective sleep quality also was included in the analysis. RESULTS: The main finding was that higher CRP indicative of systemic inflammation was correlated with lower volume of PSD. There was an association between lower EVF and Hb levels and lower volume of PSD, but this finding could be explained by confounders such as age, sex and disease. Confounders also explained a correlation between EVF and CSF clearance variables. Impaired subjective sleep quality was associated with markers of systemic inflammation, but not with PSD volume. CONCLUSION: Higher CRP was correlated with lower volume of PSD suggesting that the size of this anatomical structure associates with systemic inflammation. Further studies are needed to determine whether PSD volume could serve as an imaging marker of systemic inflammation.