高剂量首次通过心肌灌注双序列法中的T2*效应

T2* effects in the dual-sequence method for high-dose first-pass myocardial perfusion.

作者信息

Gatehouse Peter, Lyne Jonathan, Smith Gillian, Pennell Dudley, Firmin David

机构信息

Cardiovascular MR Unit, Royal Brompton Hospital, and Imperial College, University of London, United Kingdom.

出版信息

J Magn Reson Imaging. 2006 Nov;24(5):1168-71. doi: 10.1002/jmri.20746.

DOI:10.1002/jmri.20746

PMID:17031839

Abstract

PURPOSE

To examine whether T2* effects reduce the accuracy of arterial input function (AIF) measurement by the dual-sequence method.

MATERIALS AND METHODS

The dual-sequence method obtains a low-resolution AIF image and high-resolution myocardial images in each cycle, with suitable T1 weightings. It was modified to assess T2* effects in the low-resolution AIF image (4.8x4.8x10 mm voxels, TE=0.58 msec) by minimizing T1 weighting in that sequence, while the myocardial sequence remained T1-weighted. In 10 patients who underwent perfusion MRI scans (0.5 M Magnevist, 0.1 mmol/kg, 15-ml flush, 7 mL/second right antecubital) the blood signal in the left ventricle (LV) was measured at the bolus peak and compared with the first cycle's fresh magnetization signal.

RESULTS

The bolus peak measured 98%+/-4% (mean+/-SD, N=20) of the value before contrast agent arrival.

CONCLUSION

T2* causes insignificant error in the dual-sequence method at the stated parameters.

摘要

目的

研究T2*效应是否会降低双序列法测量动脉输入函数（AIF）的准确性。

材料与方法

双序列法在每个周期中获取具有合适T1加权的低分辨率AIF图像和高分辨率心肌图像。通过最小化该序列中的T1加权来对其进行修改，以评估低分辨率AIF图像（体素大小为4.8x4.8x10 mm，TE = 0.58毫秒）中的T2*效应，而心肌序列仍保持T1加权。对10例接受灌注MRI扫描的患者（0.5 M马根维显，0.1 mmol/kg，15 ml冲洗液，7 mL/秒经右肘前静脉注射），在团注峰值时测量左心室（LV）中的血液信号，并与第一个周期的新鲜磁化信号进行比较。