Diffusional kurtosis imaging evaluation on the protective effect of limb remote ischemic preconditioning against stroke

Objective To explore the changes in diffusional kurtosis imaging (DKI) parameters after limb remote ischemic preconditioning (LRP) in experimental stroke. Methods Total 26 adult SD male rats were subjected to LRP group and sham surgery (IC group) and then subsequently underwent 1 h right middle cerebral artery occlusion (MCAo).MRI examination was executed at 48 h after reperfusion to collect data of T2 FLAIR and DKI. Results T2 FLAIR result showed that the lesion in LRP group was much smaller than that in IC group (29.80±11.09 vs.59.35±13.23,P<0.05).There were much differences in DKI parameters[mean kurtosis (MK),K_⊥,K_‖]between affected side and healthy side in IC group,whereas in LRP group,the DKI parameters showed in affected side were much closer to contralateral side.The percent changes of metrical parameters with statistical differences between LRP and IC group include MK in gray matter (GM,-3.52±22.57 vs.59.73±11.63,P<0.05).MK in white matter (WM,3.99±5.32 vs.42.57±1.94,P<0.01) and K_⊥in WM as well (-16.45±4.43 vs.19.73±5.86,P<0.01).The percent in change of K‖revealed no difference between LRP and IC group (47.40±29.20 vs.71.49±15.58,P>0.05). Conclusion LRP could improve the abnormalities in DKI metrics against ischemia,which also offer us clue for explore the neuroprotective mechanism of LRP against stroke.