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Objective To analyse and summarize the MRI characteristics of tumor‐like inflammatory demyelinating diseases (TIDD) .Methods MRI findings of 10 cases with pathologically proved TIDD were analyzed retrospectively ,all patients received plain and enhanced MRI scan .Results 3 cases showed multiple lesions in bilateral frontal and parietal lobes ,and 7 cases showed soli‐tary mass ,in which 2 lesions located in the occipital lobe ,2 in the basal ganglia ,2 in the second to fifth segment of cervical cord ,and 1 lesion located in the left frontal parietal lobe .The shape of 7 lesions were irregular ,2 were stripped ,while 1 lesion was oval .6 cases had clear boundary ,while 4 showed ambiguous .Solitary lesions were 1 .7 cm -5 .6 cm in diameter(mean 4 .0 cm ± 1 .48 cm) .8 cases manifested mild edema while 2 had no edema .On MRI plain scan ,lesions were hypointensity on T1WI and hyperintensity on T2WI in 8 cases ,isointensity on T1 WI and hyperintensity on T2 WI in 2 cases ,and all lesions were hyperintensity on FLAIR sequence .DWI were performed in 3 cases ,all lesions showed hyperintensity ,2 of them had patchy hypointensity signal .Hemorrhage was detected in 3 lesions ,cystic lesions or calcification were not found in all cases .On post‐contrast scan ,3 lesions showed ring like enhancement ,2 showed obviously heterogeneous enhancement ,2 had mild enhancement and 2 cases had no enhancement ,1 presented with open ring like enhancement .Conclusion TIDD shows some specific MRI features ,and MRI is helpful to the diagnosis of TIDD .
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Objective To characterize the MRI features of demyelinating pseudotumors(DPTs).Methods MR data of 10 cases clinically proved with DPTs were retrospectively analyzed .All cases were underwent MRI scan ,9 of 10 cases were performed with enhanced MRI,7 cases were underwent diffusion weight imaging(DWI),2 cases were performed with single voxel short echo 1 H-MRS.Results 8 cases showed lesions with mild to moderate edema,5 cases showed multiple lesions,3 cases were solitary nodular lesions,2 cases were solitary flaky lesions.On enhanced MRI,4 cases presented with open ring like enhancement,3 cases presented ring like enhancement,1 case with nodular enhancement,and 1 case showed patchy enhancement.All lesions showed high signal in DWI.In 1 H-MRS,2 cases demonstrated varying decrease in peaks heights of Nacetylaspartate(NAA),elevation of the choline(Cho),the lactate(Lac)and lipids(1ip).1 case demonstrated evident elevation in peaks height of glutamate/glutamine(Glx).Conclusion DPTs has some characteristics on MRI, especially as open ring like enhancement.It is helpful to identified DPTs from other lesions when together with DWI and 1 H-MRS.
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Objective To explore the characteristics of MRI images and pathological features of demyelinating pseudotumor (DPT).Methods Five patients with demyelinating pseudotumor were histologically confirmed.Their MR imaging were re-viewed and the enhancement patterns were analyzed.Results Among the five cases with demyelinating pseudotumor,single le-sion was found in 4 cases,and multiple lesions in 1 case.Most lesions had a clear boundary and these space occupying lesions were irregular (3 cases).The signal intensity on T1 WI was lower than edema,and it had a specific “core and halo”feature,du-al-high signal with different intensity on T2 WI,slightly higher signal intensity on DWI,and on enhanced MRI,nodular or patch-y enhancement and open ring enhancement with edema around the lesions were observed.The pathological results showed that the demyelination occurred but the neuraxon survived,lymphocytes were infiltrated,glial cells were proliferated,megakaryo-cytes also could be found,and multiple monocyte-macrophages were all around the lesions.Conclusion The MRI of DPT has some characteristic features.
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Objective To analyze the MRI findings and study the correlations between pathologic, clinical and MRI findings of demyelinating pseudotumor in brain. Methods Pathologic,clinical and MRI findings in 8 cases proved pathologically with demyelinating pseudotumor in brain were retrospectively analyzed. Results The clinical manifestations comprised mostly dyskinesia and/or limb sensory disability, as well as epilepsy in few cases. MRI showed a single focal lesion mainly invading subcortical white matter in every case, and most lesions were showed round or nearly round with clear boundary, homogenous low signal on T1WI and high signal on T2WI, and marked enhancement. Pathological examination showed demyelinating, perivascular inflammatory infiltration consisting predominantly of lymphocytes, and glial cell proliferation. Conclusions MRI can well mirror the pathological and clinical changes of demyelinating pseudotumor in brain, so MRI plays an important role in its diagnosis. It is easy to make a differential diagnosis between glioma and supratentorial demyelinating pseudotumor, but it is difficult for those lesions in cerebellum. For such cases, both clinical and MRI diagnosis are necessary. Trial treatment of corticoids or even biopsy is available for those cases that are difficult to diagnose by clinical and MRI methods.