Chang Yun-Woo, Yoon Hye-Kyung, Shin Hyung-Jin, Roh Hong Gee, Cho Jae Min
Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong, Kangnam-gu, Seoul 135-710, Korea.
Pediatr Radiol. 2003 Dec;33(12):836-42. doi: 10.1007/s00247-003-0968-8. Epub 2003 Oct 17.
Glioblastoma is relatively uncommon in childhood and maybe difficult to differentiate from other brain tumors such as primitive neuroectodermal tumor, ependymoma, or benign astrocytoma.
To describe the characteristic MR features in children with glioblastoma and to evaluate the usefulness of diffusion and perfusion MR imaging and MR spectroscopy in pediatric glioblastoma.
MR imaging in 11 children (12 tumors) with biopsy-proven glioblastoma was reviewed retrospectively. In one patient, there was a recurrent glioblastoma. We reviewed CT and MRI imaging for tumor location, density/signal intensity, and enhancement pattern. Routine MR imaging was performed with a 1.5-T scanner. In six patients, diffusion-weighted MR images (DWIs) were obtained with a single-shot spin echo EPI technique with two gradient steps, and apparent diffusion coefficients (ADCs) were calculated. Using the gradient EPI technique, perfusion-weighted MR images (PWIs) were obtained in four patients from the data of dynamic MR images. The maximum relative cerebral blood volume (rCBV) ratio was calculated between the tumor and contralateral white matter in two cases. In three patients, proton MR spectroscopy was performed using a single voxel technique with either STEAM or PRESS sequences. The locations of the tumor were the thalamus and basal ganglia ( n=8), deep white matter ( n=3), and brain stem ( n=1).
Intratumoral hemorrhage was seen in four tumors. The tumors showed high-signal intensity or DWIs, having a wide range of ADC values of 0.53-1.30 (mean +/-SD=1.011+/-0.29). The maximum rCBV ratios of glioblastoma were 10.2 and 8.5 in two cases. MR spectroscopy showed decreased N-acetylaspartate (NAA) and increased choline in three cases. The MR findings of glioblastoma in children were: a diffusely infiltrative mass with hemorrhage involving the deep cerebral white matter, thalami, and basal ganglia.
Diffusion/perfusion MR imaging and MR spectroscopy are very helpful in diagnosing glioblastoma, determining the biopsy site, and evaluating tumor recurrence.
胶质母细胞瘤在儿童中相对少见，可能难以与其他脑肿瘤如原始神经外胚层肿瘤、室管膜瘤或良性星形细胞瘤相鉴别。
描述儿童胶质母细胞瘤的特征性磁共振成像（MR）表现，并评估扩散加权和灌注MR成像以及磁共振波谱在儿童胶质母细胞瘤中的应用价值。
回顾性分析11例（12个肿瘤）经活检证实为胶质母细胞瘤患儿的MR成像资料。其中1例为复发性胶质母细胞瘤。我们回顾了CT和MRI成像，观察肿瘤的位置、密度/信号强度及强化方式。采用1.5-T扫描仪进行常规MR成像。6例患儿采用单次激发自旋回波EPI技术、两个梯度步长获取扩散加权MR图像（DWI），并计算表观扩散系数（ADC）。4例患儿采用梯度EPI技术，从动态MR图像数据中获取灌注加权MR图像（PWI）。2例计算肿瘤与对侧白质之间的最大相对脑血容量（rCBV）比值。3例患儿采用单体素技术，利用STEAM或PRESS序列进行质子磁共振波谱分析。肿瘤位于丘脑和基底节（8例）、深部白质（3例）及脑干（1例）。
4个肿瘤可见瘤内出血。肿瘤在DWI上呈高信号，ADC值范围较宽，为0.53 - 1.30（平均±标准差 = 1.011±0.29）。两例胶质母细胞瘤的最大rCBV比值分别为10.2和8.5。磁共振波谱分析显示3例N - 乙酰天门冬氨酸（NAA）降低、胆碱升高。儿童胶质母细胞瘤的MR表现为：深部脑白质、丘脑及基底节区的弥漫性浸润性肿块伴出血。
扩散/灌注MR成像及磁共振波谱分析对胶质母细胞瘤的诊断、确定活检部位及评估肿瘤复发非常有帮助。
