PURPOSE: This study was designed to evaluate early parenchymal changes of acute cerebral ischemia / infarct by using T2-weighted, diffusion-weighted, and calculated apparent diffusion coefficient (ADC) MR imaging. MATERIALS AND METHODS: The brain MR images were successfully obtained 30, 60, 90, 120, 150 and 180 minutes after intraarterial administration of Lipiodol (0.4 - 0.6 ml) into the common carotid artery in 10 of 11 cats (91%). T2-and diffusion-weighted images and ADC were analyzed and compared with histopathologic findings. RESULTS: High signal intensity on T2-weighted and diffusion-weighted images was found in one cerebral hemisphere 30 minutes after Lipiodol injection, which tended to increase with time until 3 hours. Subcortical white matter showed higher signal intensity than cortical gray matter since 30 minutes after embolization. ADC images showed decreased signal intensity in the embolized hemisphere, which tended to decrease until 3 hours. Microscopic findings of the area corresponding to the abnormal signal intensity on MR images revealed varying degrees of edema in the gray and white matters involved. CONCLUSION: It is suggested that Lipiodol can be used as a good embolic agent causing early ischemic changes in experimental models. In addition to T2-weighted images, diffusion-weighted and ADC images can provide the further informations in the evaluation of the early parenchymal changes of cerebral infarct.