Hillenbrand Claudia M, Jesberger John A, Wong Eddy Y, Zhang Shaoxiong, Chang David T, Wacker Frank K, Lewin Jonathan S, Duerk Jeffrey L
Department of Radiology, University Hospitals of Cleveland, Cleveland, Ohio 44106, USA.
J Magn Reson Imaging. 2006 Feb;23(2):135-44. doi: 10.1002/jmri.20497.
To assess magnetic resonance (MR) pulse sequences for high resolution intravascular imaging.
Intravascular imaging of the abdominal aorta and iliac arteries was performed in vivo in a porcine model at 1.5 T using catheter-mounted micro-receive coils. Ten protocols, including spin-echo (SE)-echo planar imaging (SE-EPI), segmented EPI, half-Fourier single-shot turbo spin-echo (HASTE), fast imaging with steady-state free precession (TrueFISP), turbo spin-echo (TSE), and SE acquisition schemes were employed in 13 trials. Images were analyzed by six expert raters with respect to wall-conspicuity, wall-to-lumen/tissue contrast, visible layers of the arterial wall, anticipated clinical usefulness, and overall image quality. Mean differences between sequence-types were evaluated using analysis of variance (ANOVA) between groups with planned comparisons.
The vessel wall was delineated in almost all protocols. Motion artifacts from physiological and device motion were reduced in fast techniques. The best contrast between the wall and surrounding tissue was provided by a HASTE protocol. Anatomic layers of the vessel wall were best depicted on dark blood T2-weighted TSE. Overall, TrueFISP was ranked highest on the remaining measures.
Dedicated catheter-coils combined with fast sequences have potential for in vivo characterization of vessel walls. TrueFISP offered the best overall image quality and acquisition speed, but suffered from the inability to delineate the multiple layers of the wall, which seems associated with dark blood- and T2-weighted contrast. We believe future intra-arterial trials should proceed from this study in normal artery imaging and initially focus on fast T2-weighted dark blood techniques in trials with pathology.
评估用于高分辨率血管内成像的磁共振（MR）脉冲序列。
在1.5T场强下，使用安装在导管上的微型接收线圈，在猪模型体内对腹主动脉和髂动脉进行血管内成像。采用了10种方案，包括自旋回波（SE）-回波平面成像（SE-EPI）、分段EPI、半傅里叶单次激发快速自旋回波（HASTE）、稳态自由进动快速成像（TrueFISP）、快速自旋回波（TSE）以及SE采集方案，共进行了13次试验。由6名专业评估人员对图像的管壁清晰度、壁与管腔/组织对比度、动脉壁可见层数、预期临床实用性以及整体图像质量进行分析。使用组间方差分析（ANOVA）及计划比较评估序列类型之间的平均差异。
几乎所有方案都能清晰显示血管壁。快速成像技术减少了生理和设备运动产生的运动伪影。HASTE方案提供了最佳的管壁与周围组织对比度。血管壁的解剖层次在黑血T2加权TSE上显示最佳。总体而言，TrueFISP在其余指标上排名最高。
专用导管线圈与快速序列相结合，具有对血管壁进行体内特征描述的潜力。TrueFISP提供了最佳的整体图像质量和采集速度，但无法清晰显示血管壁的多层结构，这似乎与黑血和T2加权对比度有关。我们认为，未来的动脉内试验应基于本研究在正常动脉成像方面展开，并在病理试验中首先关注快速T2加权黑血技术。
