超高场强小动物磁共振成像活体观察小鼠颈动脉内膜损伤后的动态变化

目的 磁共振成像(MRI)活体观察内膜损伤后小鼠颈动脉管腔狭窄和管壁增厚的动态过程.方法 金属丝损伤法建立小鼠颈动脉内膜损伤模型,术后不同的时间点行MRI扫描,动态观察损伤血管的表现,包括管腔内径和面积、管壁的厚度和面积.结果 MRI能够清晰地观察小鼠颈动脉内膜损伤后的变化以及血管周围软组织的表现.小鼠颈动脉内膜损伤前、损伤后1、5、10d和15d管腔内径分别为(0.57±0.07)、(0.41±0.19)、(0.44±0.10)、(0.43±0.10)mm和(0.47±0.11)mm.管腔面积分别为:(0.30±0.06)、(0.18±0.11)、(0.18±0.06)、(0.18±0.06)mm2和(0.22±0.07)mm2.术后第15天患侧血管壁厚度为(0.23±0.12)mm,管壁面积为(0.35±0.24)mm2.结论 MRI可以在活体观察小鼠颈动脉内膜损伤后管腔狭窄和管壁增厚的动态变化过程.

Dynamically observing carotid artery intimal injury in mice using 7T micro-MR imaging

Objective To dynamically observe stenosis and wall thickness of carotid artery with endothelium injury in mouse using 7T micro-MR imaging in vivo. Methods A mouse model of carotid artery intimal injury was established by removing endothelium with a flexible wire. The lumen diameter, lumen area, wall thickness and wall area of the injured arteries were observed, and serial MR scanning was performed in different time points after operation. Results The injured arteries and perivascular parenchyma were clearly observed by MR imaging. Before and 1, 5, 10 and 15 days after artery injury, the lumen diameter were (0.57±0.07)mm,(0.41±0.19)mm, (0.44±0.10)mm, (0.43±0.10)mm and (0.47±0.11)mm respectively, and the lumen area were (0.30±0.06)mm2, (0.18±0.11)mm2, (0.18±0.06)mm2, (0.18±0.06)mm2 and (0.22±0.07)mm2. The thickness of artery wall was(0.23±0.12)mm, and the area of artery wall was (0.35±0.24)mm2 15days after artery injury. Conclusions Stenosis and wall thickening of carotid artery after the artery intimal injury of mouse can be dynamically observed on MR imaging in vivo.