Evaluation of the effect of cerebral oxygen saturation on infarct progression in patients with acute ischemic stroke based on MR quantitative magnetic susceptibility mapping / 中华放射学杂志

ABSTRACT

Objective:To explore the effect of dynamic changes of cerebral oxygen saturation before and after treatment on the progression of infarction in patients with acute ischemic stroke (AIS).Methods:Totally 39 patients with first onset AIS within 24 hours in Tianjin First Central Hospital and Shanghai Fourth People′s Hospital Affiliated to Tongji University from May 2018 to July 2020 were enrolled retrospectively. All patients underwent multi-modal MR at admission (baseline) and within 2 weeks after standardized treatment, including diffusion weighted imaging (DWI), susceptibility weighted imaging (SWI), and dynamic magnetic sensitive contrast-enhanced magnetic resonance perfusion imaging (DSC-PWI). The degree of asymmetrically prominent cortical vein (APCV) at admission was observed on SWI, and the venous oxygen saturation (SvO 2) of APCV on the infarcted cerebral hemisphere was calculated in all patients before and after treatment. The original DWI and DSC-PWI images obtained from two MR scans were imported into the software to obtain the delayed perfusion volume [peak time (T max)>6 s] and the infarct core volume (apparent diffusion coeffivient value<620×10 -6 mm 2/s). According to the comparison of baseline infarct core (DWI-ASPECT) score and follow-up (FUP-ASPECT) score, all patients were divided into infarct progression group (27 cases) and non-infarct progression group (12 cases). Two independent sample t-test or Mann Whitney U-test were used to compare the differences of baseline infarct core volume, baseline SvO 2, SvO 2 change, baseline hypoperfusion volume and hypoperfusion volume change between the two groups. Univariate analysis and multivariate logistic regression analysis were used to obtain independent predictors of infarct progression. Pearson correlation analysis was used to evaluate the correlation between SvO 2 change, hypoperfusion volume change and infarct change score respectively. Results:Difference in baseline infarct core volume, baseline SvO 2, hypoperfusion volume and hypoperfusion volume change between infarct progression group and non-progression group had no statistical significance ( P>0.05). There was significant difference in the change of SvO 2 between the infarct progression group and non-infarct progression group after treatment [(27±11)%, (35±6)% respectively, t=-2.56, P=0.015]. Univariate logistic regression analysis showed that the change value of SvO 2 was the influencing factor of infarction progression of AIS (OR=0.872, 95%CI 0.773-0.984, P=0.026). Multivariate logistic regression analysis showed that the baseline NIHSS score (OR=1.248, 95%CI 1.042-1.494, P=0.016) was an independent predictor of infarction progression in AIS, and the change value of SvO 2 (OR=0.814, 95%CI 0.688-0.964, P=0.017) was an independent protective factor. The change of SvO 2 was positively correlated with the score of infarct change ( r=0.425, P=0.007). Conclusions:The change of SvO 2 after AIS treatment can independently predict the progress of acute infarction. Improvement of SvO 2 after treatment is conducive to delay the progress of infarction.