Ewing James R, Nagaraja Tavarekere N, Aryal Madhava P, Keenan Kelly A, Elmghirbi Rasha, Bagher-Ebadian Hassan, Panda Swayamprava, Lu Mei, Mikkelsen Tom, Cabral Glauber, Brown Stephen L
Department of Neurology, Henry Ford Hospital, Detroit, MI, USA.
Department of Neurology, Wayne State University, Detroit, MI, USA.
NMR Biomed. 2015 Nov;28(11):1557-69. doi: 10.1002/nbm.3418. Epub 2015 Oct 1.
MRI estimates of extracellular volume and tumor exudate flux in peritumoral tissue are demonstrated in an experimental model of cerebral tumor. Peritumoral extracellular volume predicted the tumor exudate flux. Eighteen RNU athymic rats were inoculated intracerebrally with U251MG tumor cells and studied with dynamic contrast enhanced MRI (DCE-MRI) approximately 18 days post implantation. Using a model selection paradigm and a novel application of Patlak and Logan plots to DCE-MRI data, the distribution volume (i.e. tissue porosity) in the leaky rim of the tumor and that in the tissue external to the rim (the outer rim) were estimated, as was the tumor exudate flow from the inner rim of the tumor through the outer rim. Distribution volume in the outer rim was approximately half that of the inner adjacent region (p < 1 × 10(-4)). The distribution volume of the outer ring was significantly correlated (R(2) = 0.9) with tumor exudate flow from the inner rim. Thus, peritumoral extracellular volume predicted the rate of tumor exudate flux. One explanation for these data is that perfusion, i.e. the delivery of blood to the tumor, was regulated by the compression of the mostly normal tissue of the tumor rim, and that the tumor exudate flow was limited by tumor perfusion.
在脑肿瘤实验模型中展示了磁共振成像（MRI）对肿瘤周围组织细胞外体积和肿瘤渗出液通量的估计。肿瘤周围细胞外体积可预测肿瘤渗出液通量。18只无胸腺RNU大鼠脑内接种U251MG肿瘤细胞，在植入后约18天用动态对比增强磁共振成像（DCE - MRI）进行研究。使用模型选择范式以及将Patlak和Logan图新颖地应用于DCE - MRI数据，估计了肿瘤渗漏边缘以及边缘外组织（外边缘）的分布容积（即组织孔隙率），以及从肿瘤内边缘通过外边缘的肿瘤渗出液流量。外边缘的分布容积约为相邻内区域的一半（p < 1×10⁻⁴）。外环的分布容积与来自内边缘的肿瘤渗出液流量显著相关（R² = 0.9）。因此，肿瘤周围细胞外体积可预测肿瘤渗出液通量速率。这些数据的一种解释是，灌注，即血液向肿瘤的输送，受肿瘤边缘大部分正常组织的压迫调节，且肿瘤渗出液流量受肿瘤灌注限制。
