Experimental study of diffussion weighted and T₂-weighted MRI in the early stage of postdecompressive brain bulk enlargement

Objective: With observation about the change process of DWI and T 2 WI in the early stage of postdecompressive brain bulk enlargement, it is proved whether brain edema occurs.Methods: DWI and T 2 WI were performed in 6 cats at four time points （before compression and 2-4-6 hours after decompression） to examine the postdecompressive brain bulk enlargement.Results: DWI and T 2 WIshowed that the postdecompressive swollen cerebral tissue shifted increasingly to the contralateral side Within 2 hours after decompression, the hypointensity signal of DWI was observed in the swollen hemisphere Within 4 hours after decompression, the high signal of T 2 WI was observed in the swollen hemisphere Conclusions:The vasogenic edema occured in the early stage （＜2 h） of the postdecompressive brain bulk enlargement