Image-Guided Bio-Molecular Interventions Research, Department of Radiology, University of Washington School of Medicine, 815 Mercer St, Seattle, WA 98109, USA.
Radiology. 2013 Aug;268(2):556-62. doi: 10.1148/radiol.13121451. Epub 2013 Mar 19.
To develop a technique with clinical 3.0-T magnetic resonance (MR) imaging to delineate local contrast agent distribution in coronary artery walls for potential molecular MR imaging-guided local gene or drug therapy of atherosclerotic coronary artery disease.
This animal protocol was approved by the institutional animal care and use committee and was in compliance with the Guide for the Care and Use of Laboratory Animals. For in vitro confirmation, human arterial smooth muscle cells (SMCs) were used to determine capability of SMCs in uptake of motexafin gadolinium (MGd) and its optimal dose. For ex vivo evaluation, a 2-mL mixture of MGd and trypan blue was locally infused into coronary artery walls of six cadaveric pig hearts with MR monitoring and an MR imaging guidewire, surface coils, or both. For in vivo validation, the balloon catheter was placed into coronary arteries of seven living pigs, and the MGd and trypan blue mixture was infused into arterial walls with MR guidance. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of coronary artery walls were recorded by using different coils between pre- and postcontrast infusion, with subsequent histologic confirmation. Paired Student t tests were used to compare average SNRs and CNRs of arterial walls before and after contrast agent infusion with different coils.
SMCs could take up MGd with the optimal concentration at 150 µmol/L. Average SNR with the MR imaging guidewire and surface coil combination was significantly higher than that with the MR imaging guidewire only or with surface coils only (P < .05), and average SNR and CNR of postinfusion MR imaging was significantly higher than that of preinfusion MR imaging (P < .05). Histologic analysis was used to confirm successful intracoronary infiltration of MGd and trypan blue within coronary artery walls.
MR imaging can be used to delineate locally infused contrast agent distribution in coronary artery walls. This establishes groundwork for development of molecular MR imaging-guided intracoronary therapy.
开发一种基于临床 3.0-T 磁共振（MR）成像的技术，以描绘冠状动脉壁内局部对比剂的分布，从而实现对动脉粥样硬化性冠状动脉疾病的分子 MR 成像引导下的局部基因或药物治疗。
本动物研究方案已获得机构动物护理和使用委员会的批准，并符合《实验室动物护理和使用指南》。为了进行体外验证，使用人动脉平滑肌细胞（SMC）来确定 SMC 摄取莫特赛芬钆（MGd）及其最佳剂量的能力。为了进行离体评估，使用 MR 监测和 MR 成像导丝、表面线圈或两者的组合，将 2-mL 的 MGd 和锥虫蓝混合物局部注入到 6 个离体猪心的冠状动脉壁内。为了进行体内验证，将球囊导管放置在 7 头活猪的冠状动脉内，并用 MR 引导将 MGd 和锥虫蓝混合物注入动脉壁内。在注入对比剂前后，使用不同的线圈记录冠状动脉壁的信噪比（SNR）和对比噪声比（CNR），并随后进行组织学确认。使用配对学生 t 检验比较不同线圈在注入对比剂前后动脉壁的平均 SNR 和 CNR。
SMC 可以摄取最佳浓度为 150μmol/L 的 MGd。MR 成像导丝和表面线圈组合的平均 SNR 明显高于仅使用 MR 成像导丝或仅使用表面线圈的 SNR（P <.05），并且注入后 MR 成像的平均 SNR 和 CNR 明显高于注入前的 SNR 和 CNR（P <.05）。组织学分析用于确认 MGd 和锥虫蓝在冠状动脉壁内的成功渗透。
MR 成像可用于描绘冠状动脉壁内局部注入的对比剂分布。这为开发分子 MR 成像引导的冠状动脉内治疗奠定了基础。
