| Abstract: | PURPOSETo determine whether secondary MR changes occur in the thalamus or the substantia nigra after middle cerebral artery (MCA) occlusion in rats.METHODSSprague-Dawley rats were subjected to MCA occlusion. At varying intervals, proton density-, T1-, and T2-weighted images were obtained with a 4.7-T superconductive MR unit.RESULTST2-weighted images revealed an area of high signal intensity in the ipsilateral substantia nigra 4 days after occlusion. A lesion of low signal intensity appeared in the ipsilateral thalamus 7 days after surgery on proton density- and/or T2-weighted images.CONCLUSIONMR showed secondary changes in the thalamus and the substantia nigra after MCA occlusion in rats. MR imaging should provide more information on the neuropathology of the delayed neuronal degeneration after cerebral ischemia. |
