Kan Peter, Liu James K, Hedlund Gary, Brockmeyer Douglas L, Walker Marion L, Kestle John R W
Department of Neurosurgery, Primary Children's Medical Center, University of Utah School of Medicine, Salt Lake City, UT 84113, USA.
Childs Nerv Syst. 2006 Nov;22(11):1435-9. doi: 10.1007/s00381-006-0229-x. Epub 2006 Sep 22.
Diffusion-weighted imaging (DWI) may enhance the radiographic diagnosis of pediatric brain tumors. This study reviews the DWI properties of pediatric brain tumors at our institution and examines their relationship to tumor grade and type.
The preoperative DWI and apparent diffusion coefficient (ADC) characteristics of brain tumors in 41 children were compared with histologic diagnosis. Signal characteristics on DWI and ADC maps correlated well with tumor grade. High-grade lesions were hyperintense on DWI and hypointense on ADC maps. Sensitivity, specificity, positive predictive value, and negative predictive value were 70, 100, 100, and 91%, respectively. Signal characteristics did not differ among different tumors of the same grade. All primitive neuroectodermal tumors showed diffusion restriction whereas none of the ependymomas did.
The signal characteristics on DWI and ADC maps appeared to be strongly correlated to grade in pediatric brain tumors and they may assist with preoperative diagnostic predictions.
弥散加权成像（DWI）可提高小儿脑肿瘤的影像学诊断水平。本研究回顾了我院小儿脑肿瘤的DWI特征，并探讨其与肿瘤分级及类型的关系。
将41例儿童脑肿瘤术前DWI及表观扩散系数（ADC）特征与组织学诊断结果进行比较。DWI及ADC图上的信号特征与肿瘤分级密切相关。高级别病变在DWI上呈高信号，在ADC图上呈低信号。敏感度、特异度、阳性预测值及阴性预测值分别为70%、100%、100%和91%。相同分级的不同肿瘤间信号特征无差异。所有原始神经外胚层肿瘤均表现为弥散受限，而室管膜瘤均无此表现。
DWI及ADC图上的信号特征与小儿脑肿瘤分级密切相关，可能有助于术前诊断预测。
