Objective To study the imaging characteristics of intracranial dysembryoplastic neuroepithelial tumors(DNT),and to evaluate the role of CT and MRI in their diagnosis.Methods We presented 8 DNTs cases confirmed histopathologically after operation.CT and MRI features were retrospectively analyzed(3 cases received MR scan only and 5 had both studies),compared with the surgical findings and pathological appearance.Results Eight patients had totally 11 tumors with multifoci in 2 cases.Six DNTs were located in the temporal lobe,1 lesion involved the parietal lobe,1 in the frontal lobe,1 in the brain stem,1 in the cerebellum,and 1 in the frontal and temporal lobe simultaneously.All lesions were observed intracortically,and partial of them extended into the subcortical location.On 5 non-contrast CT scans,3 DNTs were homogeneously hypodense;1 case contained isodense nodules within the hypodense focus.Peripheral spotty calcification was found in 1 case.On pre-contrast MR images,all lesions showed hypointense on T_1-weighted images,moreover,multicystic change with more markedly decreased signal intensity was observed.The DNT had a well-demarcated,multinodular gyriform configuration,or a soap bubble appearance at the cortical margin.On T_2-weighted images,high signal intensity of the tumors was seen except for hypointense calcification.The bone remodeling of the adjacent calvaria was noticed in(1 case.) The tumors had slightly increased signal intensity on FLAIR(fluid attenuated inversion recovery) in 2 cases,and homogeneously mild hyperintense on PDW(proton density weighted imaging),while the isointense focus was observed in one case on DWI(diffusion weighted imaging).No obvious enhancement was identified except 1 lesion with mild enhancement following intravenous administration of contrast material.3 tumors had ill-defined contours,whereas the others showed well-demarcated margins.No surrounding vasogenic edema was present except 2 foci with slight edema.Conclusion DNT usually shows characteristic radiologic findings,in combination with the clinical presentation and history,the diagnostic accuracy should be improved,and,as such,unnecessary radiation and/or chemotherapy may be avoided.

Establishing an effective three-dimensional (3D) culture system to better model human neurological diseases is desirable, since the human brain is a 3D structure. Here, we demonstrated the development of a polydimethylsiloxane (PDMS) pillar-based 3D scaffold that mimicked the 3D microenvironment of the brain. We utilized this scaffold for the growth of human cortical glutamatergic neurons that were differentiated from human pluripotent stem cells. In comparison with the 2D culture, we demonstrated that the developed 3D culture promoted the maturation of human cortical glutamatergic neurons by showing significantly more MAP2 and less Ki67 expression. Based on this 3D culture system, we further developed an disease-like model of traumatic brain injury (TBI), which showed a robust increase of glutamate-release from the neurons, in response to mechanical impacts, recapitulating the critical pathology of TBI. The increased glutamate-release from our 3D culture model was attenuated by the treatment of neural protective drugs, memantine or nimodipine. The established 3D human neural culture system and TBI-like model may be used to facilitate mechanistic studies and drug screening for neurotrauma or other neurological diseases.