He Taigang, Gatehouse Peter D, Anderson Lisa J, Tanner Mark, Keegan Jennifer, Pennell Dudley J, Firmin David N
Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital and Imperial College, London, UK.
J Magn Reson Imaging. 2006 Sep;24(3):580-5. doi: 10.1002/jmri.20681.
To develop a reproducible fast spin-echo (FSE) technique for accurate myocardial T2 measurement with application to iron overload assessment in thalassemia.
An FSE sequence was developed to permit acquisition of multiple TE images in one breathhold (BH-FSE). A dynamic black-blood scheme was introduced to better cancel blood signal. A nonselective refocusing train was also adopted to suppress stimulated echoes. The optimized technique was tested on phantoms and then applied to 10 normal volunteers and 10 thalassemia patients. Interstudy reproducibility was measured on all the 20 subjects.
The mean difference in T2 values was 1.7% from phantom experiments between BH-FSE and the conventional spin-echo (SE) technique. High contrast BH-FSE images were acquired from human subjects, with minimal stimulated echoes and effective blood suppression (P = 0.0005). The coefficient of variation for interstudy reproducibility was 4.3%. T2 values from thalassemia patients were substantially lower than those from the normal subjects (45.2 +/- 26.1 msec vs. 56.9 +/- 8.4 ms, P = 0.02).
The dynamic black-blood T2 sequence is a fast reproducible acquisition that compares favorably with conventional techniques, is robust to motion artifacts, and yields high blood-myocardium contrast. This technique may provide a useful tool in thalassemia and other scenarios requiring myocardial T2 quantification.
开发一种可重复的快速自旋回波（FSE）技术，用于准确测量心肌T2，并应用于地中海贫血铁过载评估。
开发了一种FSE序列，以便在一次屏气（BH-FSE）中采集多个TE图像。引入动态黑血方案以更好地消除血液信号。还采用了非选择性重聚焦脉冲串来抑制受激回波。在体模上测试优化后的技术，然后应用于10名正常志愿者和10名地中海贫血患者。对所有20名受试者测量研究间的可重复性。
在体模实验中，BH-FSE与传统自旋回波（SE）技术之间T2值的平均差异为1.7%。从人体受试者获得了高对比度的BH-FSE图像，受激回波最少，血液抑制有效（P = 0.0005）。研究间可重复性的变异系数为4.3%。地中海贫血患者的T2值显著低于正常受试者（45.2±26.1毫秒对56.9±8.4毫秒，P = 0.02）。
动态黑血T2序列是一种快速可重复的采集方法，与传统技术相比具有优势，对运动伪影具有鲁棒性，并产生高血液-心肌对比度。该技术可能为地中海贫血和其他需要心肌T2定量的情况提供一种有用的工具。
