胚胎发育不良性神经上皮肿瘤的影像学诊断

Imaging Diagnosis of Dysembryoplastic Neuroepithelial Tumors

目的探讨胚胎发育不良性神经上皮肿瘤(DNT)的影像学特点。资料与方法回顾性分析经病理证实的7例DNT的影像学表现。7例中5例行CT平扫;7例均行MRI平扫,其中5例同时行MRI增强扫描;2例行18F-FDG正电子发射体层摄影(PET)检查。结果7例中5例位于颞叶,1例位于顶叶,1例同时累及额颞叶;病变均位于皮层区。CT像上4例呈均匀低密度,1例呈低、等混杂密度,其中3例可见邻近颅骨变薄;MRI上病变呈均匀或不均匀长T1、长T2信号,除1例外其他均无明显的占位效应和周围水肿;MRI增强检查3例无明显强化,2例可见结节状或点状强化;PET检查2例均呈低代谢。结论DNT的临床和影像学表现有一定特点,联合应用多种影像学检查方法有助于病变的术前诊断。

Objective To explore the imaging characteristics of dysembryoplastic neuroepithelial tumors （DNT）. Materials and Methods 7 patients with pathologically proved DNT were retrospectively reviewed, included 5 patients with plain CT scan, 7 patients with plain MR scan, 5 patients with enhanced MR scan, 2 patients with 18F FDG PET. Results All lesions were located in cortical region, including temporal lobe （5 cases）, parietal lobe （ 1 case） and frontotemparal lobe （ 1 case） . Hypodensity was seen on CT in all cases except one of mixed hypo and isodensity, bone thinning of the adjacent calvaria could be seen in 3 cases, homogeneous or heterogeneous long T1 and long T2 signal intensity were seen on MR, no obvious mass effect and peritumoral edema could be found in all cases except 1 case. On past contrast MRI scan, no obvious enhancement （3 cases） or nodular enhancement （2 cases） could be seen, glucose hypometabelism.was depicted on PET. Conclusion To a certain extent, the clinical manifestation and imaging findings of DNT are characteristic. It is helpful for preoperative diagnosis of DNT to combine various imaging modalities.