Diffusion and perfusion weighted imaging in quantization of ischemic penumbra in brain of rabbits

Objective: To discuss the value of diffusion weighted imaging (DWI) and perfusion weighted imaging (PWI) in the evaluation of ischemic penumbra (IP) salvaged.Methods: Fifty-eight successful models of middle cerebral artery occlusion (MCAO) with rabbits were randomly divided into permanent ischemic group (A group) and ischemic reperfusion group (B group).The A group was further divided into ischemic 1h,3h,6h,12h,24h,48h groups (Ai-6 group).The B group was further divided into reperfusion Oh,2h,5h,11h,23h,47h groups (B_(1-6) group) after ischemic lh.Then every group was examined with modalities including DWI and PWI.Results: The area of the abnormal signal intensity on DWI in ischemic reperfusion group was significantly smaller than that in permanent ischemic group at the same time; at ischemic 24h,the area of infarction got smooTh1y.At ischemic lh,if the ADC,rCBV,rMTT ratio of region of interest changed respectively during(73.40 ± 4.33)%,(46.83 ± 9.89)% and 1.58±0.04,it might be IP,but if the ADC,rCBV ratio of region of interest changed below respectively(58.83 ± 6.06)%,(22.87 ± 8.19)%,and the rMTT ratio of region of interest was higher than 1.94 ± 0.11,it would become inreverdible necrosis.Conclusion: Combined DWI with PWI could evaluate IP quickly and efficiently.