Evaluation of collateral circulation and short-term prognosis of patients with acute cerebral infarction by perfusion-weighted MRI.

BACKGROUND

Perfusion-weighted magnetic resonance imaging (MRI) can evaluate collateral circulation in patients with acute cerebral infarction by reflecting hemodynamic signals in the brain. The purpose of this study was to evaluate the collateral circulation and short-term prognosis of patients with acute cerebral infarction, using perfusion-weighted MRI.

METHODS

The study enrolled 206 patients with acute cerebral infarction due to unilateral cerebral artery occlusion diagnosed by digital subtraction angiography (DSA) and computed tomography angiography (CTA). The relative cerebral blood volume (rCBV), relative cerebral blood flow map (rCBF), relative peak time (rTTP), and relative mean transit time (rMTT) were calculated based on the ratio of the perfusion-weighted MRI reference values of the infarcted side and the control side of the patient. According to the results of perfusion-weighted MRI, patients were divided into a high perfusion group (n=121) and a low perfusion group (n=85). The Thrombolysis in Cerebral Infarction scale proposed by Higashida et al. in 2003 (Higashida scale) was used to evaluate the establishment of collateral circulation on the day of admission and 15 days after admission. The National Institutes of Health Stroke Scale (NIHSS) score and the modified Rankin scale assessed the short-term prognosis of patients with cerebral infarction. The Spearman correlation analysis examined the correlation between the rCBV, rCBF, and NIHSS scores, and the modified Rankin scale (mRS).

RESULTS

Compared with the patients in the low perfusion group, the rCBV and rCBF in the infarcted area of the patients in the high perfusion group were significantly increased and the rTTP and rMTT were significantly decreased. On day 15 after admission, the collateral circulation rate of the high perfusion group was significantly higher than that of the low perfusion group, and the NIHSS score and the mRS score were significantly lower than those scores of the low perfusion group. Perfusion-weighted MRI indexes, rCBV, and rCBF were negatively correlated with the NIHSS score and Rankin scale.

CONCLUSIONS

Perfusion-weighted MRI can effectively evaluate the compensatory ability of collateral circulation and the prognosis of patients with acute cerebral infarction.