Department of Neurosurgery, Shanghai Tenth People's Hospital, Tongji University School of Medicine, No. 301 Middle Yanchang Road, Shanghai, 200072, China.
Department of Radiology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, No. 301 Middle Yanchang Road, Shanghai, 200072, China.
Neurol Sci. 2021 Dec;42(12):5171-5175. doi: 10.1007/s10072-021-05226-x. Epub 2021 Apr 1.
Both brain abscess(BA)and glioblastoma (GBM) are common causative pathologies of intraparenchymal ring-enhancing lesions. Advanced MR sequences such as diffusion weighted image (DWI) were often used to increase distinguishability of both entities.
To evaluate the value of asphericity (ASP) from conventional T1-weighted MR images in differentiating BA from morphologically similar ring-enhancing GBM.
Twenty-one BA and twenty-nine GBM were retrospectively included in this study. Each region of interest (ROI) was delineated twice with the software of ITK-SNAP on the contrast-enhanced T1 images by two observers. ASP was calculated to define the relative deviation of the ROI's shape from a sphere. Intraclass correlation coefficients (ICC) for inter-observer and intra-observer were calculated. The diagnostic capabilities of ASP and conventional volume (VOL) of ROI were evaluated with receiver operating characteristic (ROC) curve analysis. In addition, areas under the ROC curves of ASP and VOL were compared.
ICC of intra-observer and inter-observer were 0.99 (95% confidence interval, [CI] 0.97-0.99) and 0.98 (0.95-0.99), respectively. Both ASP and VOL showed significant difference between BA and GBM. The mean ASP values for BA and GBM were 66.3±7.8 and 14.7±1.8, respectively. The mean VOL value of BA was also larger than that of GBM (47.2±7.4 vs. 20.7±1.5 mm). The mean AUC of ASP and VOL were 0.977 (95% CI 0.944-1) and 0.86 (95% CI 0.746-0.974), respectively. The AUC of ASP was significantly higher than that of VOL (p=0.04). The optimal cut point values of ASP and VOL were 24.39 and 24.86 mm, respectively.
ASP derived from routine MRI is useful in differentiating BA from GBM.
脑脓肿（BA）和胶质母细胞瘤（GBM）都是脑内环状增强病变的常见病因。扩散加权成像（DWI）等高级磁共振序列常用于提高两者的可区分性。
评估常规 T1 加权磁共振图像中的各向异性（ASP）在区分形态相似的环状增强 GBM 与 BA 中的价值。
本研究回顾性纳入 21 例 BA 和 29 例 GBM。两名观察者使用 ITK-SNAP 软件在增强 T1 图像上对每个感兴趣区（ROI）进行两次勾画。计算 ASP 以定义 ROI 形状相对于球体的相对偏差。计算观察者间和观察者内的组内相关系数（ICC）。采用受试者工作特征（ROC）曲线分析评估 ASP 和 ROI 常规体积（VOL）的诊断能力。此外，比较了 ASP 和 VOL 的 ROC 曲线下面积。
观察者内和观察者间的 ICC 分别为 0.99（95%置信区间，[CI]0.97-0.99）和 0.98（0.95-0.99）。BA 和 GBM 之间的 ASP 和 VOL 均有显著差异。BA 和 GBM 的平均 ASP 值分别为 66.3±7.8 和 14.7±1.8。BA 的平均 VOL 值也大于 GBM（47.2±7.4 比 20.7±1.5mm）。ASP 和 VOL 的平均 AUC 分别为 0.977（95%CI0.944-1）和 0.86（95%CI0.746-0.974）。ASP 的 AUC 显著高于 VOL（p=0.04）。ASP 和 VOL 的最佳截断值分别为 24.39 和 24.86mm。
常规 MRI 衍生的 ASP 有助于区分 BA 和 GBM。
