Arterial input functions (AIFs) measured directly from arteries with low and standard doses of contrast agent, and AIFs derived from reference tissues

作者：Wang Shiyang; Fan Xiaobing; Medved Milica; Pineda Federico D; Yousuf Ambereen; Oto Aytekin; Karczmar Gregory S^*

来源：Magnetic Resonance Imaging, 2016, 34(2): 197-203.

DOI：10.1016/j.mri.2015.10.025

• Dynamic contrast enhanced MRI (DCE-MRI) of prostate cancer
• Empirical mathematical model (EMM)
• Arterial input AIF)
• Contrast agent dose
• First pass peak
• Reference tissue method

Measurements of arterial input AIF) can have large systematic errors at standard contrast agent doses in dynamic contrast enhanced MRI (DCE-MRI). We compared measured AIFs from low dose (AIF(LD)) and standard dose (AIF(SD)) contrast agent injections, as well as the AIF derived from a muscle reference tissue and artery (AIF(ref)). Twenty-two prostate cancer patients underwent DCE-MRI. Data were acquired on a 3 T scanner using an mDixon sequence. Gadobenate dimeglumine was injected twice, at doses of 0.015 and 0.085 mmol/kg. Directly measured AIFs were fitted with empirical mathematical models (EMMs) and compared to the AIF derived from a muscle reference tissue (AIF(ref)). EMMs accurately fitted the AIFs. The 1st and 2nd pass peaks were visualized in AIF(LD), but not in AIF(SD), thus the peak and shape of AIF(SD) could not be accurately measured directly. The average scaling factor between AIF(SD) and AIF(LD) in the washout phase was only 56% of the contrast dose ratio (similar to 6:1). The shape and magnitude of AIF(ref) closely approximated that of AIF(LD) after empirically determined dose-dependent normalization. This suggests that AIF(ref) may be a good approximation of the local AIF.

• 出版日期2016-2