DYNAMIC GD-DTPA ENHANCED MRI MEASUREMENT OF TISSUE CELL-VOLUME FRACTION
DYNAMIC GD-DTPA ENHANCED MRI MEASUREMENT OF TISSUE CELL-VOLUME FRACTION
复制标题
DOI：
10.1002/mrm.1910340320
复制
发表时间：
1995-09-01
影响因子：
3.3
通讯作者：
ROSEN, BR
中科院分区：
文献类型：
--
作者：
DONAHUE, KM;WEISSKOFF, RM;ROSEN, BR
本文描述了一种测量组织细胞体积分数的新技术，该技术基于改进的Gd-DTPA动态分布和质子交换效应的建模，该技术使用峰值T-1增强和血液中Gd-DTPA浓度来计算组织细胞体积分数，该技术的可行性通过计算机模拟来证明，该模拟探索了简化假设（血管空间小，血管外质子交换缓慢）的局限性。通过对大鼠模型中肌肉、肝脏和肿瘤组织的MR和放射性核素细胞分数测量结果的直接比较，计算机模拟表明，在缓慢到中等血管质子交换和血管分数小于10%的情况下，我们的细胞分数测量结果的误差通常保持在10%以下，与这一预测一致。核磁共振和放射性核素测量细胞分数的直接比较表明，平均百分比差异小于10%：肌肉为1.9% (n = 4)；肝脏9% (n = 1)，肿瘤9.5% （n = 4）。同样，在所有研究的大鼠中，mr测量的细胞组分(肌肉（0.92 +/- 0.04,n = 20）；肝脏（0.76 +/- 0.11,n = 9）；整个肿瘤（0.69 +/- 0.15,n = 22）)与文献报道的细胞分数值一致。总的来说，作者的结果证明了一种测量组织细胞分数的简单方法的可行性，该方法在广泛的血管体积、流量和交换条件下都是稳健的，因此，该方法可能被证明是评估肿瘤对治疗反应的重要手段。关键词：细胞分数；Gd-DTPA;质子交换。
A new technique for measuring tissue cellular volume fraction, based on an improved modeling of the dynamic distribution of Gd-DTPA and the effect of proton exchange, is described, This technique uses peak T-1 enhancement and blood Gd-DTPA concentration to compute tissue cellular volume fraction, The feasibility of this technique is demonstrated with computer simulations that explore the limits of the simplifying assumptions (small vascular space, slow vascular-extravascular proton exchange), and by direct comparison of MR and radionuclide cell fraction measurements made in muscle, liver, and tumor tissue in a rat model, The computer simulations demonstrate that with slow to intermediate vascular proton exchange and vascular fractions less than 10% the error in our cell fraction measurements typically remains less than 10%, Consistent with this prediction, a direct comparison between MR and radionuclide measurements of cell fraction demonstrates mean percent differences of less than 10%: 1.9% in muscle (n = 4); 9% in liver (n = 1) and 9.5% in tumor (n = 4), Similarly, for all rats studied, the MR-measured cell fractions (muscle (0.92 +/- 0.04, n = 20); liver (0.76 +/- 0.11, n = 9); whole tumor (0.69 +/- 0.15, n = 22)) agree with the cell fraction values reported in the literature, In general, the authors' results demonstrate the feasibility of a simple method for measuring tissue cell fraction that is robust across a broad range of vascular volume, flow, and exchange conditions, Consequently, this method may prove to be an important means for evaluating the response of tumors to therapy, Key words: Cell fraction; Gd-DTPA; proton exchange.