MR detection of secondary changes remote from ischemia: preliminary observations after occlusion of the middle cerebral artery in rats.
OBJECTIVE
To determine whether secondary MR changes occur in the thalamus or the substantia nigra after middle cerebral artery (MCA) occlusion in rats.


METHODS
Sprague-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.


RESULTS
T2-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.


CONCLUSIONS
MR 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.
Nakane
M
M
Department of Neurosurgery, Teikyo University School of Medicine, Itabashi-ku, Tokyo, Japan.
Tamura
A
A
Nagaoka
T
T
Hirakawa
K
K
D000818:Animals; D001157:Arterial Occlusive Diseases / Q000175:diagnosis* / Q000209:etiology; D002533:Cerebral Angiography; D002536:Cerebral Arteries / Q000000981:diagnostic imaging* / Q000473:pathology; D002544:Cerebral Infarction / Q000150:complications / Q000175:diagnosis*; D003937:Diagnosis, Differential; D004195:Disease Models, Animal; D008279:Magnetic Resonance Imaging; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012680:Sensitivity and Specificity; D013378:Substantia Nigra / Q000000981:diagnostic imaging / Q000473:pathology; D013788:Thalamus / Q000000981:diagnostic imaging / Q000473:pathology; D014057:Tomography, X-Ray Computed; D014855:Wallerian Degeneration