Résumé
Clinical and imaging data of 11 patients with dysembryoplastic neuroepithelial tumors (DNET) and 15 patients with low-grade glioma (LGG) admitted in Northern Jiangsu People's Hospital were analyzed retrospectively.Routine MRI scan,diffusion weighted imaging (DWI) and enhanced scan were performed.The workstation automatically generated apparent diffusion coefficient (ADC) maps and then to obtain ADC values of the tumor parenchymal area and the contralateral normal reference area.Relative tumor/reference ADC values (rADC) were also calculated.The ADC values of parenchymal regions of tumor and contralateral normal reference areas and the rADC between DNET and LGG were compared.There was significant difference in age distribution between the two groups [(16.6± 13.1) vs.(43.0± 19.2) years,t=3.938,P＜0.01].Six out of 11 DNET cases and none of 15 LGG cases were cuneiform or fan-shaped (P＜0.01);5/11 DNET and 0/15 LGG showed circular high signal in fluid attenuated inversion recovery-T2 weighted imaging (T2FLAIR) sequence (P＜0.01),while there no significant differences in intracapsular segmentation,peritumor edema and mass effect,enhancement,and skull compression between two groups (all P＞0.05).The ADC values of tumor parenchymal regions in both groups were significantly higher than those in contralateral reference regions (both P＜0.01),the rADC of DNET was significantly higher than that of LGG (P＜0.01).It is difficult to identify DNET and LGG by conventional image morphology,however the rADC value of DNET in DWI is significantly higher than that of LGG,and can provide important reference for differential diagnosis between them.