胶质母细胞瘤（GBM）是最常见的脑部原发性侵袭性肿瘤。使用传统的 MRI 成像技术区分 GBM 患者的病变复发和不同类型的治疗相关变化仍然具有挑战性。因此，准确区分真实进展或假反应对于决定适当的治疗过程至关重要。这项回顾性研究调查了源自扩散加权成像 (DWI) 的表观扩散系数 (ADC) 图值作为一种无创方法来提高治疗反应诊断准确性的潜力。一组 21 名胶质母细胞瘤患者（平均年龄：59.2 ± 11.8，选择接受贝伐单抗治疗的 12 名男性、9 名女性。 ADC 值是根据 1.5-T 和 3-T MRI 扫描仪的标准化脑协议获得的 DWI 图像计算得出的。计算 rADC 值的比率。根据特征性成像特征（明确的扩散受限区域，在数周内持续扩散受限，没有组织体积损失和缺乏对比增强），将病变分类为贝伐单抗诱导的细胞毒性。将 rADC 值与我们之前研究中得出的放射性坏死和复发性病变的值进行比较。使用 p < 0.05 的非参数 Wilcoxon 符号秩检验来确定显着性。所选患者的平均±标准差年龄为 59.2±11.8。贝伐珠单抗诱导的细胞毒性的 ADC 值和相应的平均 rADC 值分别为 248.1 ± 67.2 和 0.39 ± 0.10。将这些结果与肿瘤进展和放射性坏死的 ADC 值和相应的平均 rADC 值进行比较。在所有三组中均观察到 rADC 值之间存在显着差异 (p < 0.001)。与肿瘤复发和放射性坏死相比，贝伐珠单抗诱导的细胞毒性具有统计学上显着较低的 ADC 值。该研究证明了 ADC 值作为非侵入性成像生物标志物用于区分复发性胶质母细胞瘤与放射性坏死和贝伐珠单抗诱导的细胞毒性的潜力。

Glioblastomas (GBM) are the most common primary invasive neoplasms of the brain. Distinguishing between lesion recurrence and different types of treatment related changes in patients with GBM remains challenging using conventional MRI imaging techniques. Therefore, accurate and precise differentiation between true progression or pseudoresponse is crucial in deciding on the appropriate course of treatment. This retrospective study investigated the potential of apparent diffusion coefficient (ADC) map values derived from diffusion-weighted imaging (DWI) as a noninvasive method to increase diagnostic accuracy in treatment response.A cohort of 21 glioblastoma patients (mean age: 59.2 ± 11.8, 12 Male, 9 Female) that underwent treatment with bevacizumab were selected. The ADC values were calculated from the DWI images obtained from a standardized brain protocol across 1.5-T and 3-T MRI scanners. Ratios were calculated for rADC values. Lesions were classified as bevacizumab-induced cytotoxicity based on characteristic imaging features (well-defined regions of restricted diffusion with persistent diffusion restriction over the course of weeks without tissue volume loss and absence of contrast enhancement). The rADC value was compared to these values in radiation necrosis and recurrent lesions, which were concluded in our prior study. The nonparametric Wilcoxon signed rank test with p < 0.05 was used for significance.The mean ± SD age of the selected patients was 59.2 ± 11.8. ADC values and corresponding mean rADC values for bevacizumab-induced cytotoxicity were 248.1 ± 67.2 and 0.39 ± 0.10, respectively. These results were compared to the ADC values and corresponding mean rADC values of tumor progression and radiation necrosis. Significant differences between rADC values were observed in all three groups (p < 0.001). Bevacizumab-induced cytotoxicity had statistically significant lower ADC values compared to both tumor recurrence and radiation necrosis.The study demonstrates the potential of ADC values as noninvasive imaging biomarkers for differentiating recurrent glioblastoma from radiation necrosis and bevacizumab-induced cytotoxicity.