Simonis Frank F J, Sbrizzi Alessandro, Beld Ellis, Lagendijk Jan J W, van den Berg Cornelis A T
Department of Radiotherapy, Imaging Division, University Medical Center Utrecht, Utrecht, the Netherlands.
Department of Radiology, University Medical Center Utrecht, Utrecht, the Netherlands.
Magn Reson Med. 2016 Oct;76(4):1236-45. doi: 10.1002/mrm.26023. Epub 2015 Nov 3.
Dynamic contrast enhanced (DCE) imaging is a widely used technique in oncologic imaging. An essential prerequisite for obtaining quantitative values from DCE-MRI is the determination of the arterial input function (AIF). However, it is very challenging to accurately estimate the AIF using MR. A comprehensive model, which uses complex data instead of either magnitude or phase, was developed to improve AIF estimation.
The model was first applied to simulated data. Subsequently, the accuracy of the estimated contrast agent concentration was validated in a phantom. Finally the method was applied to existing DCE scans of 13 prostate cancer patients.
The complex signal method combines the complementary strengths of the magnitude and phase method, increasing the precision and accuracy of concentration estimation in simulated and phantom data. The in vivo AIFs show a good agreement between arterial voxels (standard deviation in the peak and tail equal 0.4 mM and 0.12 mM, respectively). Furthermore, the dynamic behavior closely followed the AIF obtained with DCE-CT in the same patients (mean correlation coefficient: 0.92).
By using the complex signal, the AIF estimation becomes more accurate and precise. This might enable patient specific AIFs, thereby improving the quantitative values obtained from DCE-MRI. Magn Reson Med 76:1236-1245, 2016. © 2015 Wiley Periodicals, Inc.
动态对比增强（DCE）成像在肿瘤成像中是一种广泛应用的技术。从DCE-MRI获得定量值的一个基本前提是确定动脉输入函数（AIF）。然而，使用磁共振准确估计AIF极具挑战性。开发了一种使用复杂数据而非幅值或相位的综合模型来改善AIF估计。
该模型首先应用于模拟数据。随后，在体模中验证估计的造影剂浓度的准确性。最后将该方法应用于13例前列腺癌患者现有的DCE扫描数据。
复杂信号方法结合了幅值法和相位法的互补优势，提高了模拟数据和体模数据中浓度估计的精度和准确性。体内AIF在动脉体素之间显示出良好的一致性（峰值和尾部的标准差分别为0.4 mM和0.12 mM）。此外，动态行为与同一患者DCE-CT获得的AIF密切相关（平均相关系数：0.92）。
通过使用复杂信号，AIF估计变得更加准确和精确。这可能实现针对患者的AIF，从而改善从DCE-MRI获得的定量值。《磁共振医学》76:1236 - 1245，2016年。©2015威利期刊公司。
