Fan Xiaobing, Karczmar Gregory S
Department of Radiology, University of Chicago, Chicago, IL 60637, USA.
Magn Reson Med. 2009 Jul;62(1):229-39. doi: 10.1002/mrm.21995.
The purpose of this research was to develop a novel numerical procedure to deconvolute the arterial input function (AIF) from contrast concentration vs. time curves and to obtain the impulse response functions (IRFs) from dynamic contrast-enhanced MRI (DCEMRI) data. Numerical simulations were performed to study variations of contrast concentration vs. time curves and the corresponding IRFs. The simulated contrast media concentration curves were generated by varying the parameters of an empirical mathematical model (EMM) within reasonable ranges based on a previous experimental study. The AIF was calculated from plots of contrast media concentration vs. time in muscle under assumption that they are well approximated by the "two-compartment model" (TCM). A general simple mathematical model of the IRF was developed, and the physiological meaning of the model parameters was determined by comparing them with the widely accepted TCM. The results demonstrate that the deconvolution procedure developed in this research is a simple, robust, and useful technique. In addition, "impulse response analysis" leads to the derivation of novel parameters relating to tumor vascular architecture, and these new parameters may have clinical utility.
本研究的目的是开发一种新的数值程序，用于从对比剂浓度与时间曲线中解卷积动脉输入函数（AIF），并从动态对比增强磁共振成像（DCEMRI）数据中获得脉冲响应函数（IRF）。进行了数值模拟以研究对比剂浓度与时间曲线以及相应IRF的变化。基于先前的实验研究，通过在合理范围内改变经验数学模型（EMM）的参数来生成模拟的对比剂浓度曲线。在假设肌肉中对比剂浓度与时间的曲线能很好地用“双室模型”（TCM）近似的情况下，从这些曲线计算AIF。开发了一个通用的简单IRF数学模型，并通过将模型参数与广泛接受的TCM进行比较来确定其生理意义。结果表明，本研究中开发的解卷积程序是一种简单、稳健且有用的技术。此外，“脉冲响应分析”可导出与肿瘤血管结构相关的新参数，这些新参数可能具有临床应用价值。
