Magnetic resonance diffusion weighted imaging in evaluating mechanical thrombectomy / 中华神经医学杂志

ABSTRACT

Objective To evaluate the efficacy of mechanical thrombectomy on embolic cerebral infarction with magnetic resonance diffusion weighted imaging (DWI). Methods Forty New Zealand white rabbits were performed carotid artery injection of blood clot emboli to induce the animal models of acute cerebral infarction; these models were equally randomized into 4 groups (n=10);non-treatment group was given no treatment; mechanical thrombectomy via femoral artery was performed under DSA 6, 8 and 12 h after the inducement in the 3 treatment groups, respectively. MR-DWI, T1WI and T2WI were performed and the apparent diffusion coefficient (ADC) and infarct volume were calculated in each group 6, 8, 12 and 24 h after the inducement. Results DWI demonstrated the ischemic area in all the 40 rabbit models at hyper-acute stage (within 6 h of inducement) with hyperintensity, while T1WI and T2WI showed normal signals. MR-DWI, T1WI and T2WI had significant difference in the relevance ratio of cerebral infarction in these rabbit models at acute stage (within 24 h of inducement, P＜0.05). The DAC value was gradually decreased and the ischemic area was gradually increased at acute stage in the rabbit models of non-treatment group and group of performing mechanical thrombectomy at the 12thh of inducement, however, rabbit models of groups of performing mechanical thrombectomy at the 6th and 8th h of inducement enjoyed the opposite position. The DAC value was higher and the ischemic area was lower 24 h after the inducement in the rabbit models of groups of performing mechanical thrombectomy the 6th and 8th h of inducement as compared with those in the non-treatment group and group of performing mechanical thrombectomy at the 12th h of inducement. Conclusion Mechanical thrombectomy at early stage enjoys significant good results; MR-DWI is a sensitive way in dynamic observing the treatment efficacy of acute cerebral infarction.