Biomedical Image Analysis, Eindhoven University of Technology, Den Dolech 2, WH 3.2a, PO Box 513, 5600 MB Eindhoven, The Netherlands.
Phys Med Biol. 2010 Aug 21;55(16):4871-83. doi: 10.1088/0031-9155/55/16/016. Epub 2010 Aug 3.
Pharmacokinetic modeling is a promising quantitative analysis technique for cancer diagnosis. However, diagnostic dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) of the breast is commonly performed with low temporal resolution. This limits its clinical utility. We investigated for a range of temporal resolutions whether pharmacokinetic parameter estimation is impacted by the use of data-derived arterial input functions (AIFs), obtained via analysis of dynamic data from a reference tissue, as opposed to the use of a standard AIF, often obtained from the literature. We hypothesized that the first method allows the use of data at lower temporal resolutions than the second method. Test data were obtained by downsampling high-temporal-resolution rodent data via a k-space-based strategy. To fit the basic Tofts model, either the data-derived or the standard AIF was used. The resulting estimates of K(trans) and v(e) were compared with the standard estimates obtained by using the original data. The deviations in K(trans) and v(e), introduced when lowering temporal resolution, were more modest using data-derived AIFs compared with using a standard AIF. Specifically, lowering the resolution from 5 to 60 s, the respective changes in K(trans) were 2% (non-significant) and 18% (significant). Extracting the AIF from a reference tissue enables accurate pharmacokinetic parameter estimation for low-temporal-resolution data.
药代动力学建模是一种有前途的癌症诊断定量分析技术。然而，乳腺的诊断性动态对比增强磁共振成像（DCE-MRI）通常具有较低的时间分辨率。这限制了它的临床应用。我们研究了一系列时间分辨率，以确定使用通过参考组织的动态数据分析获得的数据衍生动脉输入函数（AIF）是否会影响药代动力学参数的估计，而不是使用标准 AIF，标准 AIF 通常是从文献中获得的。我们假设第一种方法允许在比第二种方法更低的时间分辨率下使用数据。通过基于 k 空间的策略对高时间分辨率的啮齿动物数据进行下采样，获得测试数据。为了拟合基本的 Tofts 模型，使用数据衍生的 AIF 或标准 AIF。将使用原始数据获得的标准估计值与使用原始数据获得的标准估计值进行比较。当降低时间分辨率时，K(trans)和 v(e)的偏差使用数据衍生的 AIF 比使用标准 AIF 时要小一些。具体来说，将分辨率从 5 秒降低到 60 秒，K(trans)的相应变化分别为 2%（无显著差异）和 18%（显著）。从参考组织中提取 AIF 可以实现低时间分辨率数据的准确药代动力学参数估计。
