CT平扫联合DWI序列对早期胶质母细胞瘤的诊断价值

The Value of Unenhanced CT Combined with DWI in the Diagnosis of Early-stage Glioblastoma

目的探讨联合应用CT平扫及含弥散加权成像(DWI)的常规MR扫描能否有助于提高早期胶质母细胞瘤中的诊断准确性。方法回顾性分析8例病理诊断为胶质母细胞瘤的颅脑MR平扫和CT平扫图像。评估MRI和CT图像上肿瘤的位置、边缘、信号强度和密度值。结果在MR影像上,所有8例病灶在T1加权像上呈等或稍低信号;T2加权像上呈高信号,边界不清。在8例患者中,DWI上病灶呈不均匀高信号者1例,呈等信号为主局部伴高信号者7例。在CT平扫上,病灶表现为低密度为主伴局部高密度者7例,病灶呈等密度者1例。DWI像上呈高信号的8例病灶于CT平扫上呈高密度者7例,呈等密度者1例。增强扫描无明显强化者7例,呈轻度强化者1例。8例病灶均无明显瘤周水肿。结论早期胶质母细胞瘤病灶边界多不清楚,多无水肿,无明显强化或仅轻度强化。病灶于CT平扫上呈高密度和DWI上呈高信号有很高的一致性,可作为诊断早期胶质母细胞瘤的特异性诊断征象,二者联合应用可有助于提高早期胶质母细胞瘤的诊断准确率。

Objective To investigate whether the combination of unenhanced CT including diffusion-weighted imaging(DWI) can improve the accuracy to early-stage glioblastoma. Methods The images of roution MR and unenhanced CT of the brain for 8 cases with pathological diagnosis of glioblastoma were analyzed retrospectively to evaluate the location, border, signal intensity, and density of the tumor. Results MR images showed that heterogeneous or slightly low signal intensity on T1 weighted image and high signal intensity on T2 weighted images were found in all 8 cases, with poorly-defined lesions. Of the eight patients, 1 case showed heterogeneously high signal intensity on DWI, and 7 cases showed homogeneous signal intensity in most areas, with high signal intensity in local areas. Unenhanced CT showed 7 cases with low-density lesions in most areas and high-density lesions in local areas, and 1 case with homogeneous density lesion. seven cases of high density and 1 case of homogeneous density showed by unenhanced CT were found in the 8 cases with DWI showing high signal intensity. There were 7 cases with no obvious enhancement and 1 case with mild enhancement. There was no obvious peritumoral edema in 8 cases. Conclusion In the early-stage of glioblastoma, the border of the lesion is not clear, and there is no edema, no obvious enhancement or only slight enhancement. The high density on unenhanced CT and high signal intensity on DWI are highly consistent, which can be seen as a specific diagnostic sign for early-stage glioblastoma. And the combination of unenhanced CT and DWI can make the diagnosis of glioblastoma more accurate.