Calamante F, Gadian D G, Connelly A
Radiology and Physics Unit, Institute of Child Health, University College London, London, UK.
Magn Reson Med. 2000 Sep;44(3):466-73. doi: 10.1002/1522-2594(200009)44:3<466::aid-mrm18>3.0.co;2-m.
Dynamic susceptibility contrast (DSC) MRI is now increasingly used for measuring perfusion in many different applications. The quantification of DSC data requires the measurement of the arterial input function (AIF) and the deconvolution of the tissue concentration time curve. One of the most accepted deconvolution methods is the use of singular value decomposition (SVD). Simulations were performed to evaluate the effects on DSC quantification of the presence of delay and dispersion in the estimated AIF. Both delay and dispersion were found to introduce significant underestimation of cerebral blood flow (CBF) and overestimation of mean transit time (MTT). While the error introduced by the delay can be corrected by using the information of the arrival time of the bolus, the correction for the dispersion is less straightforward and requires a model for the vasculature.
动态磁敏感对比(DSC)磁共振成像目前在许多不同应用中越来越多地用于测量灌注。DSC数据的量化需要测量动脉输入函数(AIF)并对组织浓度-时间曲线进行反卷积。最被认可的反卷积方法之一是使用奇异值分解(SVD)。进行了模拟以评估估计的AIF中存在延迟和弥散对DSC量化的影响。发现延迟和弥散都会导致脑血流量(CBF)的显著低估和平均通过时间(MTT)的高估。虽然延迟引入的误差可以通过使用团注到达时间的信息来校正,但弥散的校正则不那么直接,需要一个血管模型。