Isotropic 3D black blood MRI of abdominal aortic aneurysm wall and intraluminal thrombus.
Isotropic 3D black blood MRI of abdominal aortic aneurysm wall and intraluminal thrombus.
复制标题
腹主动脉瘤壁和腔内血栓的各向同性3D黑血MRI。
DOI：
10.1016/j.mri.2015.10.002
复制
发表时间：
2016-01
影响因子：
2.5
通讯作者：
Saloner D
中科院分区：
文献类型：
--
作者：
Zhu C;Haraldsson H;Faraji F;Owens C;Gasper W;Ahn S;Liu J;Laub G;Hope MD;Saloner D
主动脉壁和腔内血栓（ILT）作为腹主动脉瘤（AAA）疾病进展的潜在标志物已被越来越多地研究。我们的目标是在临床可接受的扫描时间内开发一种用于AAA壁和ILT成像的高分辨率3D黑血MR技术。22例AAA患者（最大直径4.3±1.0cm），沿着5例健康志愿者，在3 T条件下，采用3DT 1加权快速自旋回波序列，使用可变翻转角序列（SPACE）和准备脉冲（DANTE）抑制血流信号。志愿者和10名患者也单独使用SPACE进行扫描以进行比较。测量信噪比（SNR）和主动脉壁/ILT与管腔对比噪声比（CNR）。由两名设盲的审查员进行定性图像评分（1-4量表），评估AAA的内腔和外壁边界。在ILT患者中，计算ILT信号强度（ILTSI）与腰大肌SI（MuscleSI）的比值，并将ILT的信号异质性定量为平均值的标准差（SD）。所有受试者均成功成像，平均扫描时间为7.8±0.7分钟。用于血液抑制的DANTE准备脉冲显著减少了SPACE中的血流伪影，管腔SNR较低（8.8 vs. 21.4，p<0.001），并改善了患者的壁/ILT至管腔CNR（9.9 vs. 6.3，p<0.001）。定性评估显示管腔边界的可视化得到改善（平均得分提高73%，p=0.01），外壁边界的可视化相当（p>0.05）。10例患者存在ILT，信号相对较高，SD较宽（平均ILTSI/MuscleSI 1.42±0.48（范围0.75-2.11）），SD/平均值为27.7%±6.6%（范围19.6% - 39.4%）。使用DANTE准备脉冲，可以在临床可接受的扫描时间内实现AAA的高分辨率3D黑血MRI，减少流动伪影。ILT的信号特征可以被量化，并且可以用于改善患者特异性风险分层。
The aortic wall and intraluminal thrombus (ILT) have been increasingly studied as potential markers of progressive disease with abdominal aortic aneurysms (AAAs). Our goal was to develop a high resolution, 3D black blood MR technique for AAA wall and ILT imaging within a clinically acceptable scan time. Twenty two patients with AAAs (maximal diameter 4.3±1.0cm), along with five healthy volunteers, were imaged at 3T with a 3D T1-weighted fast-spin-echo sequence using variable flip angle trains (SPACE) with a preparation pulse (DANTE) for suppressing blood signal. Volunteers and ten patients were also scanned with SPACE alone for comparison purposes. The signal to noise ratio (SNR) and the aortic wall/ILT to lumen contrast to noise ratio (CNR) were measured. Qualitative image scores (1–4 scale) assessing the inner lumen and outer wall boundaries of AAA were performed by two blinded reviewers. In patients with ILT, the ratio of ILT signal intensity (ILTSI) over psoas muscle SI (MuscleSI) was calculated, and the signal heterogeneity of ILT was quantified as standard deviation (SD) over the mean. All subjects were imaged successfully with an average scan time of 7.8±0.7 minutes. The DANTE preparation pulse for blood suppression substantially reduced flow artifacts in SPACE with lower lumen SNR (8.8 vs. 21.4, p<0.001) and improved the wall/ILT to lumen CNR (9.9 vs. 6.3, p<0.001) in patients. Qualitative assessment showed improved visualization of lumen boundaries (73% higher scores on average, p=0.01) and comparable visualization of outer wall boundary (p>0.05). ILT was present in ten patients, with relatively high signal and a wide SD (average ILTSI/MuscleSI 1.42±0.48 (range 0.75–2.11) ) and with SD/mean of 27.7%±6.6% (range 19.6% – 39.4%). High resolution, 3D black blood MRI of AAAs can be achieved in a clinical accepted scan time with reduction of flow artifacts using the DANTE preparation pulse. Signal characteristics of ILT can be quantified and may be used for improved patient-specific risk stratification.