Dumoulin C L, Buonocore M H, Opsahl L R, Katzberg R W, Darrow R D, Morris T W, Batey C
General Electric Research and Development Center, Schenectady, New York.
Magn Reson Med. 1994 Sep;32(3):370-8. doi: 10.1002/mrm.1910320312.
A technique for the assessment of single kidney hemodynamic functions utilizing a novel MR pulse sequence in conjunction with MR contrast material administration is described. Renal extraction fraction (EF) is derived by measuring the concentration of the incoming contrast agent in the renal artery and the outgoing concentration in the renal vein. The glomerular filtration rate (GFR) can then be determined by the product of EF and renal plasma flow. A modified inversion recovery MR pulse sequence is used to measure the T1 of moving blood. This pulse sequence uses a spatially nonselective inversion pulse. A series of small flip angle detection pulses are then used to monitor the recovery of longitudinal spin magnetization in an image plane intersecting the renal vessels. The recovery rate is measured in each vessel and the T1 of blood determined. These T1 measurements are then used to determine the ratio of contrast concentration in the renal arteries and veins. Blood flow measurements can be obtained simultaneously with T1 measurements by inserting flow-encoding magnetic field gradients into the pulse sequence. Preliminary results in human volunteers suggest the feasibility of noninvasively determining hemodynamic functions with magnetic resonance.
描述了一种利用新型磁共振脉冲序列并结合磁共振造影剂给药来评估单肾血流动力学功能的技术。通过测量肾动脉中流入造影剂的浓度和肾静脉中流出造影剂的浓度来得出肾提取分数（EF）。然后，肾小球滤过率（GFR）可通过EF与肾血浆流量的乘积来确定。一种改良的反转恢复磁共振脉冲序列用于测量流动血液的T1。该脉冲序列使用空间非选择性反转脉冲。然后使用一系列小翻转角检测脉冲来监测与肾血管相交的图像平面中纵向自旋磁化的恢复情况。在每个血管中测量恢复率并确定血液的T1。然后，这些T1测量值用于确定肾动脉和肾静脉中造影剂浓度的比值。通过在脉冲序列中插入流动编码磁场梯度，可以与T1测量同时获得血流测量值。人类志愿者的初步结果表明，利用磁共振非侵入性确定血流动力学功能是可行的。
