摘要
目的探讨颅内胚胎发育不良性神经上皮肿瘤(DNT)的影像学表现,评价CT和MR I对该类肿瘤的诊断价值。方法经手术病理证实的胚胎发育不良性神经上皮肿瘤8例,回顾分析其CT(5例,另3例未行CT检查)及MR表现,并与手术、病理相对照。结果本组8例11个病灶,其中2例为多发病灶。颞叶6个病灶(6/11),顶叶、额叶、脑干及小脑各1个病灶,同时累及额颞叶者1例。所有病灶均位于皮层或部分病灶同时累及皮层下白质。5例CT平扫中,3例呈较均匀低密度;1例在低密度病灶中尚可见等密度小结节灶;1例可见边缘小斑块状钙化。8例MR平扫,T1W I,病灶均呈低信号,部分可见多个小囊状更低信号区。病灶外形欠规则呈多结节融合的脑回状或局部脑回不同程度扩大呈皂泡样隆起。T2W I除钙化斑呈低信号外,余均呈均匀高信号。1例可见病灶局部颅骨内板受压呈轻微弧形改变。2例行液体抑制反转恢复序列(FLAIR),所有病灶均呈略高信号;2例行质子密度加权成像(PDW),病灶呈均匀略高信号;1例尚行扩散加权成像(DW I),病灶显示等信号。增强检查,除1个病灶轻微强化外,余病灶均未见增强表现。3个病灶边界欠清晰,余病灶均可见清晰边界。2个病灶显示轻微瘤周水肿,余病灶均未见瘤周水肿表现。结论胚胎发育不良性神经上皮肿瘤(DNT)的影像学表现具有一定的特征性,仔细分析并结合病史可大大提高该类肿瘤的诊断正确率。
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 beth studies), compared with the surgical findings and pathological appearance. Results Eight patients had totally 11 tumors with multi-foci 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 noncontrast 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 T1-weighted images, moreover, multicystic change with more markedly decreased signal intensity was observed. The DNT had a well-demarcated, muhinedular gyriform configuration, or a soap bubble appearance at the cortical margin. On T2-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.
出处
《中华放射学杂志》
CAS
CSCD
北大核心
2006年第5期485-489,共5页
Chinese Journal of Radiology
关键词
肿瘤
神经上皮
脑肿瘤
磁共振成像
体层摄影术
X线计算机
Neoplasms, neuroepithelial
Brain neoplasms
Magnetic resonance imaging
Tomography, X-ray computed