Utz Wolfgang, Niendorf Thoralf, Wassmuth Ralf, Messroghli Daniel, Dietz Rainer, Schulz-Menger Jeanette
Franz Volhard Klinik, Charite Campus Buch, Helios Klinikum-Berlin at the Max Delbrück Center for Molecular Medicine, Wiltbergstrasse 50, 13125 Berlin, Germany.
J Magn Reson Imaging. 2007 Jun;25(6):1131-5. doi: 10.1002/jmri.20910.
To determine the regime of linear contrast enhancement in human first-pass perfusion cardiovascular magnetic resonance (CMR) imaging to improve accuracy in myocardial perfusion quantification.
A total of 10 healthy subjects were studied on a clinical 1.5T MR scanner. Seven doses of Gd-DTPA ranging from 0.00125 to 0.1 mmol/kg of body weight (b.w.) were administered as equal volumes by rapid bolus injection (6 mL/second). Resting periods of 15 minutes were introduced after delivery of Gd doses >0.01 mmol/kg b.w. For each subject, two series of rest perfusion scans were performed using two different multislice saturation-recovery perfusion sequences. Maximum contrast enhancement and maximum upslope were obtained in the blood pool of the left ventricular (LV) cavity and in the myocardium. The range of linear contrast-dose relation was determined by linear regression analysis.
MR signal intensity increased linearly for contrast agent concentrations up to 0.01 mmol/kg b.w. in the LV blood pool and up to 0.05 mmol/kg b.w. in the myocardium. For Gd concentrations exceeding these thresholds the signal intensity response was not linear with respect to the contrast agent dose.
Quantitative evaluation of cardiac MR perfusion data needs to account for signal saturation in both the LV blood pool and the myocardium.
确定人体首过灌注心血管磁共振成像（CMR）中线性对比剂增强的机制，以提高心肌灌注定量的准确性。
在一台临床1.5T MR扫描仪上对10名健康受试者进行研究。通过快速团注（6 mL/秒）以等体积给予7剂钆喷酸葡胺，剂量范围为0.00125至0.1 mmol/kg体重（b.w.）。给予剂量>0.01 mmol/kg b.w.的钆后引入15分钟的静息期。对于每个受试者，使用两种不同的多层饱和恢复灌注序列进行两组静息灌注扫描。在左心室（LV）腔的血池和心肌中获得最大对比剂增强和最大斜率。通过线性回归分析确定线性对比剂剂量关系的范围。
在LV血池中，对比剂浓度高达0.01 mmol/kg b.w.，在心肌中高达0.05 mmol/kg b.w.时，MR信号强度呈线性增加。对于超过这些阈值的钆浓度，信号强度响应与对比剂剂量不成线性关系。
心脏MR灌注数据的定量评估需要考虑LV血池和心肌中的信号饱和。
