MRI Features of Dysembryoplastic Neuroepithelial Tumor / 实用放射学杂志

Objective To investigate MRI features of dysembryoplastic neuroepithelial tumor(DNT).Methods The MR images of ten cases with surgically and pathologically proved DNT were retrospectively reviewed.Results MR imaging showed cystic component with mural nodule in 6,mainly cystic component with septa in 3.The solid components of the tumors were long T_1 and long T_2 signal intensity,the cystic components were even longer T_1 and T_2 signal intensity which resembled the signal of cerebrospinal fluid.Mild enhancement could be found at the intra-tumoral solid nodule or septations after injection of constrast medium but the cystic component did not show any enhancement.No peri-tumoral edema and mass effect were found in most cases.Conclusion DNTs are of some special features on the MR images,the diagnosis can be exactly done before operation if MRI features in combination with clinical data of the patients.

A Case of Recurrent Dysembryoplastic Neuroepithelial Tumor in the Temporal Lobe / 대한간질학회지

A boy since 6 years of his age who have had complex partial seizure was referred to our Department in March 1998. The left anterior temporal lobectomy with the resection of the head and body of hippocampus and gross total tumor removal was also performed in April 1998. He has been seizure free and stable about 3 years postoperatively. In January 2001, he revisited us due to headache, nausea, and vomiting from one week before. MRI revealed recurrence of the tumor, and a partial removal of the tumor was performed. Nine months from the second operation, the tumor recurred again and the thrid operation was followed. The pathologic findings were dysembryoplastic neuroepithelial tumor (DNT) in all three cases and no evidences of anaplastic changes were found in two recurrent cases. In general, DNT is known to be a disease that rarely transforms into the malignant, postoperative adjuvant radio-or chemotherapy is unnecessary even after partial resection of the tumor. However, in our case, there were two episodes of recurrence after the total resection. Here, we report the first case of recurrent DNT even after the total resection within three years in our knowledge.

Coexistence of Neoplasia and Cortical Dysplasia Associated with Intractable Epilepsy: A Clinical Study of Seven Surgical Patients and Surgical Strategies

A tumor and cortical dysplasia may be the concomitant cause of the causes of intractable epilepsy, but a few studies have examined so far. From among 249 patients who underwent surgery for intractable epilepsy at Dongsan Epilepsy Center, those in whom neoplasia and cortical dysplasia coexisted were selected for this study, and were reviewed the clinical, electrophysiological, neuroimaging and pathological findings. In 17 of 25 lesionrelated epilepsy patients, tumors including dysembryoplastic neuroepithelial tumor(DNT)(n=6), ganglioglioma(n=5), gangliocytoma(n=1), low grade astrocytoma(n=2), oligodendroglioma(n=2), hypothalamic hamartoma(n=1) were verified. Of these 17 cases involving tumors, concomitant cortical dysplasia was observed in 7(DNT; 6, ganglioglioma; 1). All these patients underwent sophisticated presurgical evaluation and intraoperative acute recording(EcoG) for the identification of adjacent or remote epileptogenic areas as well as functional brain mapping by electrical stimulation or SSEP to verify the eloquent areas. In intractable epilepsy, the coexistence of cortical dysplasia and neoplasia is not common, though careful intraoperative evaluation of the tumor and surrounding tissue using electrocorticogram (EcoG) may lead to its pathological identification and excellent surgical results for these rare lesions.