Johansson L O, Ahlström H K
Department of Diagnostic Radiology, Uppsala University Hospital, Sweden.
Acta Radiol. 1998 Sep;39(5):579-82. doi: 10.1080/02841859809172230.
To determine the correlation between dose rate and T1 in blood at Gd-enhanced MR angiography (MRA).
A test dose of contrast agent was used to calculate the time delay between injection and arrival in the abdominal aorta. The dose rate was expressed as ml.kg b.w.-1.s-1. The correlation between dose rate and T1 was determined by varying the dose rate while keeping the scanning and infusion times constant. The signal intensity in the abdominal aorta was measured during the first pass of Gd and compared with markers of known T1 values.
A correlation between dose rate and T1 in blood was obtained.
A Gd dose rate of 0.01 ml.kg b.w.-1.s-1 gives a T1 in blood of 100 ms. This can be used to calculate the optimal pulse sequence for contrast-enhanced MRA.
确定钆增强磁共振血管造影（MRA）中剂量率与血液T1之间的相关性。
使用测试剂量的造影剂计算注射与到达腹主动脉之间的时间延迟。剂量率表示为毫升·千克体重-1·秒-1。在保持扫描和输注时间恒定的情况下改变剂量率，以确定剂量率与T1之间的相关性。在钆首次通过期间测量腹主动脉中的信号强度，并与已知T1值的标记物进行比较。
获得了剂量率与血液T1之间的相关性。
钆剂量率为0.01毫升·千克体重-1·秒-1时，血液T1为100毫秒。这可用于计算对比增强MRA的最佳脉冲序列。
