MR imaging of myeloperoxidase activity in a model of the inflamed aneurysm wall.
MR imaging of myeloperoxidase activity in a model of the inflamed aneurysm wall.
复制标题
DOI：
10.3174/ajnr.a4135
复制
发表时间：
2015-01
期刊：
影响因子：
--
通讯作者：
Bogdanov AA Jr
中科院分区：
文献类型：
--
作者：
Gounis MJ;van der Bom IM;Wakhloo AK;Zheng S;Chueh JY;Kühn AL;Bogdanov AA Jr
虽然髓过氧化物酶(MPO)在体内的活性可以使用非侵入性成像进行可视化，但成功的临床翻译需要进一步优化成像方法。我们报道了一种运动敏化驱动平衡(MSDE)，用于在实验性动脉瘤模型中检测MPO活性特异性Gd(Gd)显像剂(IA)，该显像剂补偿了动脉瘤中的不规则血流，使得能够在动脉瘤中进行血管壁成像。我们部署了一个体模模型来优化MSDE MR序列，该序列抑制了动脉瘤内复杂的血流模式，以检测MPO特异性的Gd-螯合物。该模型是通过旋转血管造影术建立的兔弹力酶动脉瘤模型，并连接到模拟兔特定血流条件的心脏脉搏复制器。此后，我们进一步改进了MSDE序列，并在体内将其应用于有和不有动脉瘤壁炎症的兔动脉瘤模型。在每种情况下，在静脉注射IA之前和之后对动脉瘤进行成像。计算各层面的信噪比(SNR)。MSDE序列被优化以减少流动信号，从而能够在模体中检测到MPO-IA。在兔囊性动脉瘤模型中，优化的成像方案显示，与单纯动脉瘤和邻近的颈动脉相比，炎性动脉瘤增强前后的信噪比信号强度的变化显著增加(p<；0.0001)。在脑动脉瘤的动物模型中，对MPO特异性分子显像剂的分子成像进行了优化。
Although myeloperoxidase (MPO) activity in vivo can be visualized using non-invasive imaging, successful clinical translation requires further optimization of the imaging approach. We report a motion-sensitized-driven-equilibrium (MSDE) for the detection of an MPO activity-specific gadolinium (Gd)-containing imaging agent (IA) in experimental aneurysm models that compensates for irregular blood flow enabling vascular wall imaging in the aneurysm. We deployed a phantom model to optimize a MSDE MR sequence that suppresses complex flow patterns within the aneurysm for detection of an MPO-specific Gd-chelate. The phantom was built from rotational angiography of a rabbit elastase aneurysm model and connected to a cardiac pulse duplicator mimicking rabbit-specific flow conditions. Thereafter, we further refined the MSDE sequence and applied it in vivo to rabbit aneurysm models with and without inflammation in the aneurysmal wall. Under each condition, the aneurysms were imaged before and after intravenous administration of the IA. The signal-to-noise ratio (SNR) of each MR slice through the aneurysm was calculated. The MSDE sequence was optimized to reduce flow signal enabling detection of the MPO-IA in the phantom. The optimized imaging protocol in the rabbit model of saccular aneurysms revealed a significant increase in the change of SNR pre- to postcontrast MR signal intensities in the inflamed aneurysms as compared to naïve aneurysms and the adjacent carotid artery (p<0.0001). A diagnostic MR protocol was optimized for molecular imaging of an MPO-specific molecular imaging agent in an animal model of brain aneurysms.