He Taigang, Gatehouse Peter D, Kirk Paul, Tanner Mark A, Smith Gillian C, Keegan Jennifer, Mohiaddin Raad H, Pennell Dudley J, Firmin David N
Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital and Imperial College, Sydney Street, London, United Kingdom.
J Magn Reson Imaging. 2007 Jun;25(6):1205-9. doi: 10.1002/jmri.20929.
To compare the effectiveness and reproducibility of a new black-blood sequence vs. a conventional bright-blood gradient-echo T2* sequence for myocardial iron overload measurement in thalassemia.
Twenty thalassemia patients were studied. Black-blood sequence images were acquired in diastole after a double inversion recovery (DIR) preparation pulse. Bright-blood sequence images were acquired in both early systole and late diastole. The data were randomized and the T2* analysis was performed blindly by two independent observers.
The T2* values from the black-blood sequence were comparable to those of the conventional bright-blood sequence (25.7 +/- 12.9 msec vs. 26.4 +/- 14.2 msec in early systole, P = 0.44; and 25.2 +/- 13.1 msec in late diastole, P = 0.41). The coefficient of variation (CV) for black-blood image T2* analysis was 4.1% compared with 8.9% (early systole P = 0.03) and 7.8% (late diastole P = 0.05) for bright-blood image analysis.
The black-blood T2* technique yields high-contrast myocardial images, provides clearly depicted myocardial borders, and avoids blood signal contamination of the myocardium while yielding improvements in interobserver variability.
比较一种新的黑血序列与传统的亮血梯度回波T2*序列在测量地中海贫血心肌铁过载方面的有效性和可重复性。
对20例地中海贫血患者进行研究。在双反转恢复(DIR)准备脉冲后的舒张期采集黑血序列图像。在收缩早期和舒张晚期采集亮血序列图像。数据随机分组,由两名独立观察者盲法进行T2*分析。
黑血序列的T2值与传统亮血序列的T2值相当(收缩早期分别为25.7±12.9毫秒和26.4±14.2毫秒,P = 0.44;舒张晚期为25.2±13.1毫秒,P = 0.41)。黑血图像T2*分析的变异系数(CV)为4.1%,而亮血图像分析在收缩早期为8.9%(P = 0.03),舒张晚期为7.8%(P = 0.05)。
黑血T2*技术可产生高对比度的心肌图像,清晰描绘心肌边界,避免心肌的血液信号污染,同时改善观察者间的变异性。