MRI of acute experimental allergic encephalomyelitis: correlation with pathology
10.3760/cma.j.jssn.1005-1201.2009.04.024
- VernacularTitle:急性实验性变态反应性脑脊髓炎模型的MRI表现及其病理基础
- Author:
Jingjing LU
;
Fang WANG
;
Zhengyu JIN
;
Yan XU
;
Hongzhi GUAN
- Publication Type:Journal Article
- Keywords:
Encephalomyelitis,autoimmuc,experimental;
Magnetic resonance imaging;
Pathology
- From:
Chinese Journal of Radiology
2009;43(4):422-426
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the MR imaging findings of acute experimental allergic encephalomyelitis(EAE) in correlation with pathology. Methods An EAE model was induced by intradermal inoculation with guinea pig CNS homogenate in 6 female Lewis rats.Another 6 rats served as control.The clinical presentation and body weight of the animals were recorded daily. Routine MRI,Gd-enhanced MRI were performed when EAE animals showed the initial symptoms. Uhrasmall superparamagnetic iron oxide(USPIO) colloid solution was also administrated intravenously and MRI was performed again after 24 hours. The brain was removed instantly after the second MR imaging. The pathological exams including HE staining,myelin sheath staining and prussian staining were performed.The imaging findings were observed in correlation with pathological results. Results The EAE rats showed decrease of body weight on the 6th to 7th day after inoculation,and the clinical symptoms appeared on the 10th to 11th day after inoculation.Routine MRI did not show any definite abnormalities.The Gd-enhanced MRI found the diffuse thickening and enhancement of brain meninges.The USPIO-enhanced MRI showedareas of low signal intensity at white matter of medulla oblongata on T2WI,and high signal intensity was observed at the corresponding area on T1 WI. Gradient T2 * WI found more foci of low signal intensity in eerebellar white matter besides the lesions in the brain stem.The range of abnormal signal intensity was larger in animal with higher clinical scores than that with lower score.There were no abnormal findings in control animaL The pathological exam found "perivascular cuff" in the brain white matter in EAE animals,some accompanied with adjacent demyelinatian. The prussian staining found blue particles within the cytoplasm of the macrophages around the lesion,which corresponded to the area of low signal intensity on T2WI.Conclusion USPIO-enhanced MRI could reveal acute EAE lesions which were not capable of being shown on routine MRI and Gd-enhanced MRI.It can image the macrophages around the lesions in vivo.USPIO is important for future research and application in MS patients.
